Articles de revues : « D1 cooling »

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Maximenko, Serguei I., Jaime A. Freitas, N. Y. Garces, E. R. Glaser et Mark A. Fanton. « Evolution of D₁-Defect Center in 4H-SiC during High Temperature Annealing ». Materials Science Forum 600-603 (septembre 2008) : 429–32. http://dx.doi.org/10.4028/www.scientific.net/msf.600-603.429.

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The behavior of the D1 center in semi-insulating 4H-SiC substrates revealed by low-temperature photoluminescence was investigated after post-growth high temperature anneals between 1400 and 2400oC. The influence of different post-anneal cooling rates was also studied. The optical signature of D1 was observed up to 2400oC with intensity maxima at 1700 and 2200oC. We propose that the peak at 1700°C can be related to the formation and subsequent dissociation of SiC native defects. It was found that changes in the post-annealing cooling rate drastically influence the behavior of the D1 center and the concentrations of the VC, VSi, VC-VSi and VC-CSi lattice defects.

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Zharov, M. V. « Analysis of features of heat transfer processes during crystallization of aluminum alloy granules in aqueous and water-vapor media ». Materials Science, n^o 8 (2023) : 3–13. http://dx.doi.org/10.31044/1684-579x-2023-0-8-3-13.

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The result analysis of the created mathematical model application of a detailed change in the temperature field and analysis of phase transitions during cooling and crystallization of a melt drop under cooling conditions in an aqueous and water-vapor medium have been carried out. The presented mathematical model allows one not only to determine the temperature fields in the body of a drop or a granule, but also determines the speed of movement of a drop in the coolant at any given time, determines the intensity of heat removal, the cooling rate and the rate of crystallization of the melt at different points in the volume. All this, in the end, makes possible to predict the size of dendrites, properties and phase composition of material of the obtained granules. The mathematical model was tested in the process of granulation of high-doped aluminum alloys (alloys D1 and D16 of the Al—Cu—Mg system, alloys B95 and B96C of the Al—Zn—Mg—Cu system) obtained by the centrifugal melt spraying method and the drip method during cooling in an aqueous medium. The crystallization rate in full-scale samples was measured on the basis of the method of analysis of the dendritic parameter of the material structure. The mathematical model showed a high degree of convergence between the results of simulation modeling and the results of real experiments for obtaining granules. In particular, the model showed fairly accurate results for the formation of granules at ultra-high crystallization rates, in the absence of a «steam jacket», namely, a steam layer arising between the body of the granule and the coolant that prevents the intensity of heat removal, and is an obstacle to increasing the crystallization rate due to a lower thermal conductivity of water vapor.

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Douzi, Wafa, Xavier Guillot, Delphine Bon, François Seguin, Nadège Boildieu, Daniel Wendling, Nicolas Tordi, Olivier Dupuy et Benoit Dugué. « 1H-NMR-Based Analysis for Exploring Knee Synovial Fluid Metabolite Changes after Local Cryotherapy in Knee Arthritis Patients ». Metabolites 10, n^o 11 (13 novembre 2020) : 460. http://dx.doi.org/10.3390/metabo10110460.

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Rehabilitation using cryotherapy has widely been used in inflammatory diseases to relieve pain and decrease the disease activity. The aim of this study was to explore the metabolite changes in inflammatory knee-joint synovial fluids following local cryotherapy treatment (ice or cold CO2). We used proton nuclear magnetic resonance (1H NMR) spectroscopy to assess the metabolite patterns in synovial fluid (SF) in patients with knee arthritis (n = 46) before (D0) and after (D1, 24 h later) two applications of local cryotherapy. Spectra from aqueous samples and organic extracts were obtained with an 11.75 Tesla spectrometer. The metabolite concentrations within the SF were compared between D1 and D0 using multiple comparisons with the application of a false discovery rate (FDR) adjusted at 10% for each metabolite. A total of 32 metabolites/chemical structures were identified including amino acids, organic acids, fatty acids or sugars. Pyruvate, alanine, citrate, threonine was significantly higher at D1 vs D0 (p < 0.05). Tyrosine concentration significantly decreases after cryotherapy application (p < 0.001). We did not observe any effect of gender and cooling technique on metabolite concentrations between D0 and D1 (p > 0.05). The present study provides new insight into a short-term effect of cold stimulus in synovial fluid from patients with knee arthritis. Our observations suggest that the increased level of metabolites involved in energy metabolism may explain the underlying molecular pathways that mediate the antioxidant and anti-inflammatory capacities of cryotherapy.

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Singh, Balkar, Sehijpal Singh, Vivek Aggarwal et Gurpreet Singh. « Modeling and Optimization of Turning Hastelloy C-276 under Sustainable Machining Environments ». Solid State Phenomena 356 (18 mars 2024) : 21–31. http://dx.doi.org/10.4028/p-bj6vjw.

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Due to their numerous applications in the aerospace, chemical, and nuclear power industries, environmentally responsible superalloy machining is a major problem in the current production environment. Additionally, Ni-based superalloys are regarded as difficult to manufacture because of their great strength under hot and chemically reactive settings. Therefore, it is necessary to machine these materials using adequate cooling and lubricating solutions. Current study has been based on the optimisation and modelling of turning Hastelloy C-276 under dry, flood, and least lubrication system. A Taguchi L-9 arrangement was used as plan of experiment and modeling was enabled through ANOVA, regression analysis and Taguchi optimization. The results depicted optimal parameters for surface roughness and temperature at v2-f1-d1-CE3 and v1-f2-d1-CE3. Likewise, for CRC and shear angle the best combination was observed at v3-f3-d2-CE2. From ANOVA analysis, the benefaction of C.E, depth of cut and feed rate on S.R been listed as 46.70%, 40.44% and 10.66%. Likewise, for temperature cutting speed has benefaction of (53.09%), cooling environment (23.94%), depth of cut (6.10%) and feed rate 5.49% . In similar fashion, CRC and Shear angle were influenced by feed rate and cutting speed having contribution of 62.89% and 5.15% respectively. Furthermore, minimum standard error between the fitted and observed values for S.R., temperature, CRC, and shear angle were calculated as 0.0149, 7.66, 0.267, and 1.80 units. Finally, the marginal reduction of cutting temperature and surface roughness through utilization of MQL implies the sustainable machining conditions.

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Mishra, Purna Chandra, Dipti Kanta Das et Susant Kumar Sahu. « Comparative Performance In Hard Turning Of AISI 1015 Steel With Carbide Insert Using Orthogonal Array Design And Grey Relational Analysis Under Spray Impingement Cooling And Dry Environment ». International Journal of Manufacturing, Materials, and Mechanical Engineering 4, n^o 3 (juillet 2014) : 1–32. http://dx.doi.org/10.4018/ijmmme.2014070101.

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This study investigates the effects of cutting parameters on surface roughness (Ra), cutting temperature (T0C) at the chip tool interface and the material removal rate (MRR mm3/min) during hard machining of AISI 1015 (43 HRC) steel using carbide insert under dry and spray impingement cooling environment. A combined technique using orthogonal array and analysis of variance (ANOVA) was employed to investigate the contribution of spindle speed, feed rate, depth of cut and air pressure on responses. Utilization of IR camera is been effective to calculate the temperature at the interface of workpiece and the tool. It is observed that with spray impingement cooling, cutting performance improves compared to dry cutting. The predicted multi response optimization setting (N3-f1-d1-P2) ensures minimization of surface roughness, cutting temperature and maximization of material removal rate. Finally optimal result was validated by confirmatory test and the improvement in grey relational grade was found to be 0.288.

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Yeargin, Susan, Amy L. McKenzie, Lindsey E. Eberman, J. Derek Kingsley, David J. Dziedzicki et Patrick Yoder. « Physiological and Perceived Effects of Forearm or Head Cooling During Simulated Firefighting Activity and Rehabilitation ». Journal of Athletic Training 51, n^o 11 (1 novembre 2016) : 927–35. http://dx.doi.org/10.4085/1062-6050-51.10.09.

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Context: Cooling devices aim to protect firefighters by attenuating a rise in body temperature. Devices for head cooling (HC) while firefighting and forearm cooling (FC) during rehabilitation (RHB) intervals are commonly marketed, but research regarding their efficacy is limited. Objective: To investigate the physiological and perceived effects of HC and FC during firefighting drills and RHB. Design: Randomized controlled clinical trial. Setting: Firefighter training center. Patients or Other Participants: Twenty-seven male career firefighters (age = 39 ± 7 years; height = 169 ± 7 cm; weight = 95.4 ± 16.8 kg). Intervention(s): Firefighters were randomly assigned to 1 condition: HC (n = 9), in which participants completed drills wearing a cold gel pack inside their helmet; FC (n = 8), in which participants sat on a collapsible chair with water-immersion arm troughs during RHB; or control (n = 10), in which participants used no cooling devices. Firefighters completed four 15-minute drills (D1−D4) wearing full bunker gear and breathing apparatus. Participants had a 15-min RHB after D2 (RHB1) and D4 (RHB2). Main Outcome Measure(s): Change (Δ) in gastrointestinal temperature (TGI), heart rate (HR), physiological strain index, and perceived thermal sensation. Results: The TGI increased similarly in the HC and control groups, respectively (D1: 0.57°C ± 0.41°C, 0.73°C ± 0.30°C; D2: 0.92°C ± 0.28°C, 0.85°C ± 0.27°C; D3: −0.37°C ± 0.34°C, −0.01°C ± 0.72°C; D4: 0.25°C ± 0.42°C, 0.57°C ± 0.26°C; P > .05). The ΔHR, Δ physiological strain index, and Δ thermal sensation were similar between the HC and control groups during drills (P > .05). The FC group demonstrated a decreased TGI compared with the control group after RHB1 (−1.61°C ± 0.35°C versus −0.23°C ± 0.34°C; P < .001) and RHB2 (−1.40°C ± 0.38°C versus −0.38°C ± 0.24°C; P < .001). The physiological strain index score decreased in the FC group compared with the control group after RHB1 (−7.9 ± 1.3 versus −2.6 ± 1.7; P < .001) and RHB2 (−7.9 ± 1.6 versus −3.6 ± 1.1; P < .001), but no differences between groups were demonstrated for ΔHR or Δ thermal sensation (P > .05). Conclusions: The HC did not attenuate rises in physiological or perceptual variables during firefighting drills. The FC effectively reduced TGI and the physiological strain index score but not HR or thermal sensation during RHB. Clinicians and firefighters should not recommend the use of HC during firefighting but can consider using FC during RHB intervals in the field.

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Talarico, F. M., E. Stump, B. F. Gootee, K. A. Foland, R. Palmeri, W. R. Van Schmus, P. K. Brand et C. A. Ricci. « First evidence of a “Barrovian”-type metamorphic regime in the Ross orogen of the Byrd Glacier area, central Transantarctic Mountains ». Antarctic Science 19, n^o 4 (2 août 2007) : 451–70. http://dx.doi.org/10.1017/s0954102007000594.

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AbstractThe Selborne Group comprises two metamorphic rock units, the muscovite±dolomite bearing Madison Marble and the biotite-muscovite±quartz-calcite Contortion Schist, which contains thick lenses of variably deformed metabasalts and metaconglomerates. Petrological and structural data indicate a polyphase metamorphic evolution including: i) an early stage of upper greenschist regional metamorphism (P = ~0.15–0.3 GPa; T = ~380–450°C), ii) prograde metamorphism during D1 up to amphibolite facies peak conditions (P = 0.58–0.8 GPa, T = ~560–645°C), iii) syn-D2 unloading-cooling retrograde metamorphism, iv) a post-D2 contact metamorphic overprint at variable T between 450 and 550°C and ~0.2 GPa connected to the emplacement of granitic plutons and felsic dyke swarms. Geochronological data constrain the polyphase syn-D1/D2 evolution between ~ 510 and 492 Ma. A similar metamorphic path, including a medium P stage but at lower T conditions, is documented in greenschist facies metabasalts within the Byrd Group in the Mount Dick area. The metamorphic pattern and close lithostratigraphic matching between Selborne Group and Byrd Group sharply contrast with the high-grade Horney Formation that is exposed north of the Byrd Glacier and corroborate the hypothesis that the Byrd Glacier discontinuity marks a first-order crustal tectonic boundary crossing the Ross orogen.

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Schulz, Bernhard. « Mineral chemistry, geothermobarometry and pre-Alpine high-pressure metamorphism of eclogitic amphibolites and mica schists from the Schobergruppe, Austroalpine basement, Eastern Alps ». Mineralogical Magazine 57, n^o 387 (juin 1993) : 189–202. http://dx.doi.org/10.1180/minmag.1993.057.387.01.

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AbstractAlternating eclogitic amphibolites, mica schists and orthogneisses in the Schobergruppe to the south of the Tauern Window suffered a post-Upper-Ordovician progressive deformation D1-D2which produced parallel planar-linear structures in all the rocks. Zoned garnets, preferentially oriented zoned clinopyroxenes (Jd 35-42%) and albite (An 7-9%) give evidence of high-pressure metamorphism (550-650°C 14-16 kbar) of the metabasites. Ca-amphiboles crystallized during subsequent decompression. In a kyanite-staurolite-garnet mica schist 300 metres below the metabasites, garnetbearing assemblages grew synchronous with the development of foliations S1and S2. Garnets are zoned with increasing XMgand decreasing-increasing-rcdecreasing Xcafrom cores to rims. Albitic plagioclase (An 1-3%) and micas are enclosed in garnet cores and rims, are in contact with garnet, and occur with garnet in microlithons. When these minerals are used for geothermobarometry, a prograde P-T evolution (460 to 680°C with coeval pressure variations which reach high-pressure conditions can be estimated. This suggests that garnet-plagioclase geobarometry with albitic plagioclase works in the relevant P-T field. Similar garnet zonation trends and a similarly shaped P-T path from mica schists of an adjacent region with late-Variscan cooling ages, points to an eady-Variscan age of the syn-D1-D2high-pressure and subsequent amphibolite-facies metamorphism.

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Hermansyah, Hermansyah, Novian Sutami et Miksusanti Miksusanti. « AMPLIFIKASI PCR DOMAIN D1/D2 28S rDNA MENGGUNAKAN PRIMER ITS1 DAN ITS4 SAMPEL DNA DARI Candida tropicalis YANG DIISOLASI DENGAN METODE PENDINGINAN ». Indonesian Journal of Pure and Applied Chemistry 1, n^o 1 (23 juillet 2018) : 1. http://dx.doi.org/10.26418/indonesian.v1i1.26037.

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The purpose of this research was to isolated DNA from the yeast C. tropicalis with freeze thawing method -200 C conducted on 3 colonies of C. tropicalis. Each colony threated variations of cooling, 3x15 minutes, 3x25 minutes and 3x35 minutes, to break the cell walls. Subsequently all the samples amplified with 3 variations of PCR cycles, 15 cycles, 25 cycles and 35 cycles, after all of the samples isolated by freeze thawing method -200 C. Its was known that sample A15 has the smallest concentration of DNA yeast C. tropicalis, ie 50 µg/mL, while sample C35 had the largest concentration of DNA yeast C. tropicalis, ie 225 µg/mL. The result of the research indicated that the best condition can be reached in 3x35 minutes. On 35th cycle has clearer C. tropicalis DNA bands than the 25th and 15th PCR cycle. C. tropicalis DNA bands at 35th cycles there were 7 DNA bands were detected and bright bands on a long 35 minutes cooling. In the 25th and the 15th cycle, there was no DNA bands were detected in all samples. Based on the results obtained, the amplification process must be carried out at least 35 times cycles so that the C. tropicalis DNA bands can be detected.

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Balogun, Kayode B., Griffin Nicholls, Olujide Sokunbi et Kara R. Stewart. « PSV-9 Effects of Natural Honey Inclusion in Dilution and Freezing Extenders on Frozen-thawed Semen Quality in Boars ». Journal of Animal Science 99, Supplement_1 (1 mai 2021) : 211. http://dx.doi.org/10.1093/jas/skab054.346.

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Abstract Improvements in the post-thaw quality of frozen semen could allow increased utilization of this technology in the swine industry. The objective of this study was to investigate the effects of natural honey inclusion in semen extender and freezing media on motility, mobility, and morphology of cryopreserved boar sperm. Ejaculates from 6 terminal cross-bred boars were collected using the gloved-hand technique for 3 weeks and used in a 2 x 3 factorial study design. Following collection, semen samples were incubated overnight in dilution extender with and without natural honey (D0: Androhep Plus; D1: Androhep Plus + 0.25% honey). The following day, the semen samples were cooled to 4 C in LEY cooling extender then frozen in freezing media containing 93% cooling extender + 6% glycerol + 1% Equex-STM Paste (F1), or freezing media with natural honey replacing 50% of the glycerol (F2) or 50% of the Equex-STM paste (F3). Semen samples were frozen using a controlled-rate freezer and stored in liquid nitrogen. Two straws per treatment for each boar were thawed and semen quality assessed. The inclusion of natural honey in dilution extender had no effect on post-thaw motility (P=0.733), progressive motility (P=0.562), or other mobility parameters (0.995≤P≥0.081). However, D1 had a higher percentage of normal acrosomes (P=0.001) and morphologically normal cells (P< 0.001) resulting from lower tail abnormalities compared to D0 (P=0.006). Post-thaw motility (P< 0.001) and progressive motility (P< 0.001) were increased in F3 compared to both F2 and F1. F1 had reduced normal acrosomes (P=0.009) and morphologically normal cells (P< 0.001) resulting from higher tail abnormalities (P< 0.001). In conclusion, the inclusion of natural honey, at 0.25%, in dilution extender helps maintain normal sperm and acrosome morphology, and replacing 50% Equex-STM Paste with honey in freezing extender improves post-thaw sperm motility and progressive motility of frozen-thawed boar semen.

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Zharov, M. V. « On a mathematical model of the cooling and crystallization of metal drops during centrifugal granulation ». Voprosy Materialovedeniya, n^o 2(114) (25 juillet 2023) : 98–112. http://dx.doi.org/10.22349/1994-6716-2023-114-2-98-112.

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A mathematical model has been developed for the crystallization of aluminum alloy granules under cooling conditions in an aqueous and water-steam media. The practical significance of the mathematical model lies in predicting the average value of the dendritic parameter of the obtained granules depending on the granulation method, the characteristics of the granulation process and the size of the obtained granules. The average value of the dendritic parameter makes it possible to predict the fineness of the granule structure and, consequently, the mechanical properties of the granular material. The mathematical model makes it possible to determine the speed of a melt drop in an aqueous media and takes into account the presence of a steam jacket effect, i.e., a vapor layer that appears between a crystallizing drop and an aqueous media, which significantly reduces the intensity of heat removal and the rate of crystallization. The application of the mathematical model was tested on the obtaining of granules of high-alloyed aluminum alloys (alloys D1 and D16 of the Al–Cu–Mg system, alloys V95 and V96Ts of the Al–Zn–Mg–Cu system), made by centrifugal spraying of the melt from a perforated rotating crucible and drip method during cooling in an aqueous media. The cooling rate and the crystallization rate of the granules obtained in real experiments were determined by measuring the dendritic parameter of the material structure. The mathematical model showed a high convergence of the simulation results and of real experiments of aluminum alloy granulation.

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Kumar, R., A. K. Sahoo, P. C. Mishra et R. K. Das. « Performance of Near Dry Hard Machining Through Pressurised Air Water Mixture Spray Impingement Cooling Environment ». International Journal of Automotive and Mechanical Engineering 16, n^o 1 (26 mars 2019) : 6108–33. http://dx.doi.org/10.15282/ijame.16.1.2019.3.0465.

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The present paper emphasizes on experimental investigation, mathematical modelling, optimisation, tool life and cost analysis during machining of AISI D2 (heat treated) (55±1 HRC) steel using uncoated carbide tool through a novel method under spray impingement cooling environment. Taguchi based L16 orthogonal array was utilised to conduct the experiments. Analysis of variance with 95% confidence level shows that the feed and depth of cut, are the most compelling factor towards surface roughness as well as chip reduction coefficient whereas cutting speed is the utmost compelling feature associated to flank wear as well as chip-tool interface temperature. Optimised result is identified as v1-f1-d1 (machining speed of 63 m/min; cutting feed of 0.04 mm/rev and depth of cut of 0.1 mm) based on grey relational analysis and tool life is found to be 15 minutes at optimised cutting conditions. Flank wear due to abrasion, catastrophic failure due to diffusion, chipping and notch wear are noticed as the major tool wear mechanisms in hard turning. Mathematical machinability models show statistically significance because due to the superior coefficient of correlations. As the global machining cost for each part is less, uncoated carbide tools can machine effectively, efficiently and economically at optimum cutting conditions under spray environment.

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Davis, W. J., N. Machado, C. Gariépy, E. W. Sawyer et K. Benn. « U–Pb geochronology of the Opatica tonalite-gneiss belt and its relationship to the Abitibi greenstone belt, Superior Province, Quebec ». Canadian Journal of Earth Sciences 32, n^o 2 (1 février 1995) : 113–27. http://dx.doi.org/10.1139/e95-010.

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U–Pb ages for zircon, monazite, and titanite from samples collected from two transects across the Opatica tonalite-gneiss belt in the Superior Province of Quebec indicate that the belt contains rocks that are significantly older than those in the adjacent low-grade northern Abitibi belt. Tonalite and tonalite gneiss, which make up most of the belt, formed over an interval of 100 Ma, from pre-2800 to 2702 Ma. Five samples have ages of ca. 2807 ± 13, 2773 ± 23, [Formula: see text], [Formula: see text], and 2702 ± 3 Ma. Zircon growth at 2718–2721 Ma in the two oldest samples may record an early period of high-grade metamorphism in the belt. Hornblende diorite, monzodiorite, and tonalite plutons were intruded at 2693–2696 Ma, particularly along the southern boundary with the Abitibi belt. These include the Canet pluton at [Formula: see text][Formula: see text] Ma, the Lac Ouescapis pluton at 2693 ± 2 Ma, and the Barlow pluton at 2696 ± 3 Ma. Pink granite plutons and dykes are the youngest intrusive rocks in the belt; three samples have yielded zircon ages of 2690 ± 2 and 2686 ± 4 Ma and a monazite age of 2678 ± 2 Ma. The timing of D1 deformation is bracketed by the age of the youngest gneiss sample containing the D1 structures, at 2702 ± 3 Ma, and the 2690 ± 2 Ma age of a granite dyke that cuts D1 structures. The south-vergent D2 event is recorded in the 2693–2696 Ma plutons and must have occurred synchronously with or after this plutonism. D3 dextral strike-slip movement on the Nottoway River shear zone occurred after 2686 ± 4 Ma, and may be associated with post-regional metamorphic titanite growth at 2672 and 2657 Ma. Titanite ages cluster at 2678–2681 Ma along the Matagami transect and at 2665 Ma north of Chibougamau, and record the time of cooling of the belt below the titanite closure temperature.

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Li, Renzheng, Yi Yang, Fengwei Liang, Jichao Liu et Xinbo Chen. « Investigation on Battery Thermal Management Based on Enhanced Heat Transfer Disturbance Structure within Mini-Channel Liquid Cooling Plate ». Electronics 12, n^o 4 (7 février 2023) : 832. http://dx.doi.org/10.3390/electronics12040832.

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The battery thermal management system plays an important role in the safe operation of a lithium-ion battery system. In this paper, a novel liquid cooling plate with mini-channels is proposed and is improved with disturbance structures. First, an accurate battery heat generation model is established and verified by experiments. The error is less than 4%, indicating the heat generation power is reliable. Then, five designs are proposed first to determine the suitable number of disturbance structures, and plan 3 with five disturbance structures shows a satisfying performance in heat dissipation and flow field. Moreover, four layout plans are proposed, namely uniform, interlaced, thinning, and gradually denser distribution. Results show that plan 5 (uniform) achieves the best performance: the maximum average temperature is 36.33 °C and the maximum average temperature difference is 0.16 °C. At last, the orthogonal experiment and range analysis are adopted to optimize the structure parameters. Results show that the best combination is space between adjacent disturbance structures d1 = 20 mm, length d2 = 5 mm, width d3 = 1.5 mm, and tilt angle β = 60°.

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Tribe, I. R., R. A. Strachan et R. S. D’Lemos. « Neoproterozoic shear zone tectonics within the Icartian basement of Guernsey and Sark, Channel Islands ». Geological Magazine 133, n^o 2 (mars 1996) : 177–92. http://dx.doi.org/10.1017/s0016756800008694.

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AbstractThe Channel Islands of Guernsey and Sark are amongst the few localities within the Neoproterozoic, Cadomian orogenic belt where Palaeoproterozoic basement is exposed. Basement units collectively referred to as ‘Icartian’ comprise orthogneisses (e.g. the c. 2000 Ma Icart granite gneiss), metasediments and amphibolites. On Guernsey, the protolith to the Icart granite gneiss was intruded into metasediments already deformed during a D1 deformation event. Both were variably deformed during a D2 event within an approximately north—south trending, steeply dipping, oblique dextral shear zone. On Sark, metasediments and amphibolites carry a D1 fabric (not necessarily correlatable with that on Guernsey) which was deformed during D2 to form recumbent—gently inclined folds and tectonic fabrics which locally carry top-to-the-south kinematic indicators. Early Cadomian quartz diorites which intruded the Icartian basement carry variably developed magmatic and moderate temperature (400–550 °C) LS solid-state fabrics which are similarly oriented to D2 basement structures. This indicates that the quartz diorites were emplaced and deformed during a protracted D2 event. Published 40Ar/39Ar amphibole cooling ages of c. 600 Ma from Guernsey and Sark quartz diorites and a host Icartian amphibolite are consistent with reworking of basement units during the Cadomian Orogeny. The contrasting kinematic pattern during Cadomian deformation implies that a flat-lying shear zone on Sark may have accommodated oblique dextral strike-slip movement on Guernsey with an overall southerly direction of tectonic transport. Deformation most likely occurred in the hanging-wall of a major south-dipping Neoproterozoic subduction zone.

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Medjahed, Driss Meddah, Giulio Lorenzini, Redha Rebhi, Hijaz Ahmad et Younes Menni. « New Approaches for Protecting the Computer and Electronic Devices Against Heat Dissipation ». International Journal of Safety and Security Engineering 11, n^o 3 (30 juin 2021) : 279–84. http://dx.doi.org/10.18280/ijsse.110308.

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This research is based on an experimental investigation of four different types of heatsinks, which was backed up by a simulation analysis. The goal of this study is to determine the relevance of various heatsink forms and sizes, as well as to enhance the best situation. The cooling strength of these heatsinks was next investigated experimentally and then numerically, while adjusting in the same initial conditions, finding in principle that the experimental and numerical results agree, with a contrast ratio of less than 10.24%. As a consequence, we concluded that the coolant D3, which is circular and has a heat resistance of 0.582 K. W-1, is stronger than the D2 compact circular cooler, which has a resistance of 0.590 K. W-1. These two varieties were far superior to the regular D1 heatsink, which first debuted in the early days of computers and had a resistance of 0.595 K. W-1, but the best was the mixed engineering D4 heatsink, which had a heat resistance of 0.50 K. W-1. Changes were also made to the geometry of the best heatsink D4, by varying its heights (28, 23, 19, and 15 mm). The heat resistors were arranged in sequence (0.50, 0.560, 0.568, 0.586 kg/s), and the weights were arranger in order (3.12N, 2.56N, 2.11N and 1.67N).

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Poklonski, N. A., S. A. Vyrko, A. I. Kovalev, I. I. Anikeev et N. I. Gorbachuk. « Design of Peltier Element Based on Semiconductors with Hopping Electron Transfer via Defects ». Devices and Methods of Measurements 12, n^o 1 (19 mars 2021) : 13–22. http://dx.doi.org/10.21122/2220-9506-2021-12-1-13-22.

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The study of thermoelectric properties of crystalline semiconductors with structural defects is of practical interest in the development of radiation-resistant Peltier elements. In this case, the spectrum of energy levels of hydrogen-like impurities and intrinsic point defects in the band gap (energy gap) of crystal plays an important role.The purpose of this work is to analyze the features of the single-electron band model of semiconductors with hopping electron migration both via atoms of hydrogen-like impurities and via their own point triplecharged intrinsic defects in the c- and v-bands, as well as to search for the possibility of their use in the Peltier element in the temperature range, when the transitions of electrons and holes from impurity atoms and/or intrinsic defects to the c- and v-bands can be neglected.For Peltier elements with electron hopping migration we propose: (i) an h-diode containing |d1)and |d2)-regions with hydrogen-like donors of two types in the charge states (0) and (+1) and compensating them hydrogen-like acceptors in the charge state (−1); (ii) a homogeneous semiconductor containing intrinsic t-defects in the charge states (−1, 0, +1), as well as ions of donors and acceptors to control the distribution of t-defects over the charge states. The band diagrams of the proposed Peltier elements in equilibrium and upon excitation of a stationary hopping electric current are analyzed.A model of the h-diode containing hydrogen-like donors of two types |d1) and |d2) with hopping migration of electrons between them for 50 % compensation by acceptors is considered. It is shown that in the case of the reverse (forward) electrical bias of the diode, the cooling (heating) of the region of the electric double layer between |d1)and |d2)-regions is possible.A Peltier element based on a semiconductor with point t-defects is considered. It is assumed that the temperature and the concentration of ions of hydrogen-like acceptors and donors are to assure all t-defects to be in the charge state (0). It is shown that in such an element it is possible to cool down the metal-semiconductor contact under a negative electric potential and to heat up the opposite contact under a positive potential.

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Uysal, M. U. « Effects of Cryogenically Treated CFRP Composite on the Buckling Behavior in the Adhesively Bonded Beam ». Journal of Engineering Sciences 10, n^o 1 (2023) : D1—D7. http://dx.doi.org/10.21272/jes.2023.10(1).d1.

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Carbon fiber reinforced plastic (CFRP) composite materials have favorable mechanical and physical properties such as low density, high strength-to-weight ratio, high fatigue resistance and high creep behavior, and high stiffness. Thanks to these unique properties, they produce aircraft parts such as outer flaps, carry-through structures, and center wing boxes and automotive parts such as body panels, engine components, and structure members. However, studies have been continuously performed on improving the properties of CFRP composite materials. Recently, investigation of the effects of cryogenic (LN2) cooling on the mechanical behavior and characteristic of these composite materials is getting a popular and important issue. In this sense, this study aims to examine the buckling behaviors of adhesively bonded beam-produced cryogenically treated carbon fiber reinforced plastic (Cryo-CFRP), CFRP, steel, and aluminum. Therefore, a new finite element model was adopted to evaluate the buckling capacity of Cryo-CFRP composite material in the adhesively bonded beam. The model is a supported adhesive beam subject to two opposite-edge compressions until the material buckles. The elastic, homogeneous adhesive was used in the assembly. Finite element models for the adhesively bonded beam having four different adherents (CRFP, Cryo-CFRP, steel, and aluminum) were established by ANSYS® software. The critical buckling loads of the adhesively bonded beam were predicted, and their mode shapes were presented for the first six modes. The effects of the usage of Cryo-CFRP on the critical buckling load were investigated. Among the adherents’ materials, the highest critical buckling load was determined for Cryo-CFRP/Steel adhesively bonded beam as 23.6 N. This value was obtained as 22.3 N for CFRP/Steel adherent samples. Thus, the critical buckling load was increased by 5.6 % when one adherent steel was constant and the other adherent material changed from CFRP to Cryo-CFRP. Also, the critical buckling load increased by 3.7 % when using a cryogenically treated Cryo-CFRP/Aluminum couple instead of a CFRP/Aluminum couple in the sandwich beam. The findings demonstrated that the cryogenic treatment positively affects the buckling behavior in the adhesively bonded beam.

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Marques, C. H., L. A. Isoldi, E. D. Dos Santos et L. A. O. Rocha. « CONSTRUCTAL DESIGN OF A VORTEX TUBE FOR SEVERAL INLET STAGNATION PRESSURES ». Revista de Engenharia Térmica 11, n^o 1-2 (31 décembre 2012) : 85. http://dx.doi.org/10.5380/reterm.v11i1-2.62005.

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The present paper shows a numerical study concerned with the geometrical optimization of a vortex tube device by means of Constructal Design for several inlet stagnation pressures. In the present study, it is evaluated a vortex tube with two-dimensional axisymmetric computational domain with dry air as the working fluid. The compressible and turbulent flows are numerically solved with the commercial CFD package FLUENT, which is based on the Finite Volume Method. The turbulence is tackled with the k-ε model into the Reynolds Averaged Navier-Stokes (RANS) approach. The geometry has one global restriction, the total volume of the cylindrical tube, and four degrees of freedom: d3/D (the ratio between the diameter of the cold outlet and the diameter of the vortex tube), d1/D (the ratio between the diameter of the inlet nozzle and the diameter of the vortex tube), L2/L (the ratio between the length of the hot exit annulus and the length of the vortextube) and D/L (the ratio between the diameter of the vortex tube and its length). The degree of freedom L2/L will be represented here by the cold mass fraction (yc). In the present work it is optimized the degrees of freedom yc and d3/D while the other degrees of freedom and the global restriction are kept fixed. The purpose here is to maximize the amount of energy extracted from the cold region (cooling effect) for several geometries, as well as, investigate the influence of the inlet stagnation pressure over the optimal geometries. Results showed an increase of the twice maximized cooling heat transfer rate of nearly 330 % from 300 kPa to 700 kPa. Moreover, the optimization showed a higher dependence of (d3/D)o for the lower range of inlet pressures, while the optimization is more dependent of yc,oo for higher inlet stagnation pressures.

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Salim, Muhammad Ade, Muhammad Nur Ihsan, Nurul Isnaini et Trinil Susilawati. « Konsentrasi Superoxydase Dismutase (SOD) dan Malondialdehyda (MDA) Semen Cair Kambing Boer selama Pendinginan Menggunakan Pengencer Air Kelapa ». Jurnal Agripet 22, n^o 1 (1 avril 2022) : 51–56. http://dx.doi.org/10.17969/agripet.v22i1.20073.

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ABSTRACT. Lama simpan semen cair yang berbahan dasar pengencer air kelapa muda varietas kelapa hijau (C.Viridis) hanya mampu bertahan selama 3 hari pada suhu 50C akibat peroksidasi lipid yang menyebabkan kerusakan membran. Penelitian ini bertujuan untuk menganalisis pengaruh penggunaan pengencer air kelapa terhadap konsentrasi Superoxydase Dismutase (SOD) dan kadar Malondialdehyda (MDA) semen cair kambing Boer selama penyimpanan dingin. Durasi penelitian satu bulan bertempat di Laboratorium Fakultas Kedokteran dan Laboratorium Reproduksi Ternak, Unit Sumber Sekar, Fakultas Peternakan, Universitas Brawijaya, Malang. Metode penelitian yaitu eksperimen. Dikoleksi dari semen 3 pejantan Boer umur 3-5 tahun interval 1 minggu 1 kali menggunakan Vagina Buatan. Air kelapa muda varietas viridis umur 5-7 bulan serta tris aminomethane sebagai kontrol. Rancangan penelitian didesain menggunakan Rancangan Acak Kelompok (RAK) dengan 2 perlakuan yaitu P0 (tris aminomethane + 10% Kuning Telur) dan P1 (air kelapa muda varietas viridis + 10% Kuning Telur) masing-masing diulang 3 kali. Data dianalisis dengan analisis Ragam (Anova) dengan software Genstat 18. Variabelnya yaitu konsentrasi SOD dan MDA. Hasil penelitian diperoleh untuk SOD P0 H1= 35,842 ± 1,82 ; H3= 33,342± 3,50 dan H8= 23,729± 9,02 dalam ng/100 ug. Untuk P1 diperoleh rerata H1 =36,676±2,19 ; H3= 36,527±2,20 ; H8= 24,830± 8,93 dalam ng/100ug. Kadar MDA P0 H1= 1,072±0,2 ; H3= 1,218± 0,4 dan H8= 1,439± 0,3 dalam ng/100ug. Hasil P1 H1= 0,941± 0,0 ; H3= 1,160± 0,4 dan H8= 1,370± 0,3. Hasil Anova Perlakuan tidak berpengaruh Nyata (P0,05) disemua hari simpan, tetapi konsentrasi SOD terbaik di P1 dibandingkan P0. Kesimpulan 1. Penggunaan air kelapa sebagai pengencer semen cair kambing Boer selama pendinginan tidak berdampak pada konsentrasi SOD dan MDA. 2. Peningkatan konsentrasi MDA dan Penurunan konsentrasi SOD disebabkan karena, rendahnya antioksidant flavonoid dan vitamin C. (Concentration of Superoxydase Dismutase (SOD) and Malondialdehyda (MDA) Goat Boer Liquid Semen during Cooling using Coconut Water Diluent) ABSTRAK. The shelf life of young coconut water thinner viridis for liquid semen quality Boer goat is only up to 3 days, because there is damage due to lipid peroxidation which causes damage to the spermatozoa membrane. This study aims to analyze the effect of using coconut water thinner on the concentration of Superoxydase Dismutase (SOD) and levels of Malondialdehyda in Boer goat liquid semen during cold storage. The duration of the research is one month at the Laboratory of the Faculty of Medicine and the Laboratory of Animal Reproduction, Sumber Sekar Unit, Faculty of Animal Husbandry, Brawijaya University, Malang. The research method is experimental. Collected from the semen of 3 Boer males aged 3-5 years 1 week interval using Artificial Vagina. Young viridis coconut water aged 5-7 months and tris aminomethane as a control. The research design was designed using a Randomized Block Design (RBD) with 2 treatments, namely T0 (tris aminomethane + 10% EY) and T1 (viridis young coconut water + 10% EY) each repeated 3 times. Data were analyzed by analysis of variance (Anova) with Genstat 18 software. The variables were SOD and MDA concentrations. The results obtained for SOD T0 D1 = 35.842 ± 1.82; D3 = 33.342 ± 3.50 and D8 = 23.729 ± 9.02 in ng / 100 ug. For T1, the mean D1 = 36.676 ± 2.19; D3 = 36,527 ± 2.20; D8 = 24,830 ± 8.93 in ng / 100ug. MDA levels T0 D1 = 1.072 ± 0.2; D3 = 1.218 ± 0.4 and D8 = 1.439 ± 0.3 in ng / 100ug. Result of T1 H1 = 0.941 ± 0.0; D3 = 1.160 ± 0.4 and D8 = 1.370 ± 0.3. The results of the ANOVA treatment had no significant effect (P 0.05) on all storage days, but the best SOD concentration was in T1 compared to T0. The conclusion is that 1. The use of coconut water as a liquid Boer goat semen thinner during cooling has no impact on the SOD and MDA concentrations. 2. Increased MDA concentrations and decreased SOD concentrations were due to low flavonoid and vitamin C antioxidants.

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Pycia, Karolina, Ewa Szupnar-Krok, Małgorzata Szostek, Renata Pawlak et Lesław Juszczak. « Effect of Soil Type and Application of Ecological Fertilizer Composed of Ash from Biomass Combustion on Selected Physicochemical, Thermal, and Rheological Properties of Potato Starch ». Molecules 27, n^o 13 (5 juillet 2022) : 4318. http://dx.doi.org/10.3390/molecules27134318.

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The aim of the study was to assess the effect of soil type and the application of fertilizer composed of ashes from biomass combustion to potatoes on selected physicochemical, rheological, and thermal properties of potato starches isolated by using the laboratory method. Potatoes were grown in Haplic Luvisol (HL) and Gleyic Chernozem (GC) soil and fertilized with different doses of biomass combustion ash (D1–D6) with different mineral contents. The thermodynamic characteristics of gelatinization and retrogradation were identified by DSC. The analyses of rheological properties included the determination of the gelatinization characteristics by using the RVA method, flow curves, and assessment of the viscoelastic properties of starch gels. It was found that the starches tested contained from 24.7 to 29.7 g/100 g d.m. amylose, and the clarity of 1% starch pastes ranged from 59% to 68%. The gelatinization characteristics that were determined showed statistically significant differences between the starches analyzed in terms of the tested factors. The value of maximum viscosity and final viscosity varied, respectively, in the range of 2017–2404 mPa·s and 2811–3112 mPa·s, respectively. The samples of the potato starches studied showed a non-Newtonian flow, shear thinning, and the phenomenon of thixotropy. After cooling, the starch gels showed different viscoelastic properties, all of which were weak gels (tan δ = G″/G′ > 0.1).

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Corrigan, David, Nicholas G. Culshaw et Jim K. Mortensen. « Pre-Grenvillian evolution and Grenvillian overprinting of the Parautochthonous Belt in Key Harbour, Ontario : U–Pb and field constraints ». Canadian Journal of Earth Sciences 31, n^o 3 (1 mars 1994) : 583–96. http://dx.doi.org/10.1139/e94-051.

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The Parautochthonous Belt in the region of Key Harbour, Ontario, is composed of Early Proterozoic migmatitic para- and orthogneiss and Mid-Proterozoic granitoids, which were reworked during the Grenville orogeny. Grenvillian deformation is localized into anastomosing arrays of high-strain shear zones enclosing elongate bands and lozenges of rock subjected to lower and near-coaxial strain. Crosscutting relationships preserved in the low-strain domains document two pre-Grenvillian plutonic and tectonometamorphic events, which are bracketed in age by U–Pb zircon geochronology. A 1694 Ma leucogranite intrudes, and provides a minimum age for, high metamorphic grade gneisses formed during an earlier tectonometamorphic event (D1–M1). The leucogranite was intruded by mafic dykes, deformed, and metamorphosed at uppermost amphibolite facies during D2–M2, before the emplacement of Mid-Proterozoic granitoids at ca. 1450 Ma. Following the emplacement of gabbro dykes and pods at ca. 1238 Ma, the area was overprinted by granulite to uppermost amphibolite facies metamorphism (Grenvillian), for which monazites provide a minimum age of ca. 1035 Ma. Titanite U–Pb ages of 1003 – 1004 Ma record cooling through 600 °C. A regionally important swarm of east–west-trending posttectonic pegmatite dykes dated by U–Pb zircon at 990 Ma provides a minimum age for Grenvillian ductile deformation. The present data support the contention that the Parautochthonous Belt in the Key Harbour area consists in part of reworked midcontinental crust of Early to Mid-Proterozoic age.

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de la Mora, Eugenio, Nicolas Coquelle, Charles S. Bury, Martin Rosenthal, James M. Holton, Ian Carmichael, Elspeth F. Garman, Manfred Burghammer, Jacques-Philippe Colletier et Martin Weik. « Radiation damage and dose limits in serial synchrotron crystallography at cryo- and room temperatures ». Proceedings of the National Academy of Sciences 117, n^o 8 (11 février 2020) : 4142–51. http://dx.doi.org/10.1073/pnas.1821522117.

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Radiation damage limits the accuracy of macromolecular structures in X-ray crystallography. Cryogenic (cryo-) cooling reduces the global radiation damage rate and, therefore, became the method of choice over the past decades. The recent advent of serial crystallography, which spreads the absorbed energy over many crystals, thereby reducing damage, has rendered room temperature (RT) data collection more practical and also extendable to microcrystals, both enabling and requiring the study of specific and global radiation damage at RT. Here, we performed sequential serial raster-scanning crystallography using a microfocused synchrotron beam that allowed for the collection of two series of 40 and 90 full datasets at 2- and 1.9-Å resolution at a dose rate of 40.3 MGy/s on hen egg white lysozyme (HEWL) crystals at RT and cryotemperature, respectively. The diffraction intensity halved its initial value at average doses (D1/2) of 0.57 and 15.3 MGy at RT and 100 K, respectively. Specific radiation damage at RT was observed at disulfide bonds but not at acidic residues, increasing and then apparently reversing, a peculiar behavior that can be modeled by accounting for differential diffraction intensity decay due to the nonuniform illumination by the X-ray beam. Specific damage to disulfide bonds is evident early on at RT and proceeds at a fivefold higher rate than global damage. The decay modeling suggests it is advisable not to exceed a dose of 0.38 MGy per dataset in static and time-resolved synchrotron crystallography experiments at RT. This rough yardstick might change for proteins other than HEWL and at resolutions other than 2 Å.

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VON GOSEN, W. « Stages of Late Palaeozoic deformation and intrusive activity in the western part of the North Patagonian Massif (southern Argentina) and their geotectonic implications ». Geological Magazine 146, n^o 1 (30 juillet 2008) : 48–71. http://dx.doi.org/10.1017/s0016756808005311.

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AbstractAnalyses of structures in the western part of the North Patagonian Massif (southern Argentina) suggest a polyphase evolution, accompanied by continuous intrusive activity. The first two deformations (D1, D2) and metamorphism affected the upper Palaeozoic, partly possibly older Cushamen Formation clastic succession and different intrusive rocks. A second group of intrusions, emplaced after the second deformational episode (D2), in many places contain angular xenoliths of the foliated country rocks, indicating high intrusive levels with brittle fracturing of the crust. Deformation of these magmatic rocks presumably began during (the final stage of) cooling and continued under solid-state conditions. It probably coincided with the third deformational event (D3) in the country rocks. Based on published U–Pb zircon ages of deformed granitoids, the D2-deformation and younger event along with the regional metamorphism are likely to be Permian in age. An onset of the deformational and magmatic history during Carboniferous times, however, cannot be excluded. The estimated ~W–E to NE–SW compression during the D2-deformation, also affecting the first group of intrusive rocks, can be related to subduction beneath the western Patagonia margin or an advanced stage of collisional tectonics within extra-Andean Patagonia. The younger ~N–S to NE–SW compression might have been an effect of oblique subduction in the west and/or continuing collision-related deformation. As a cause for its deviating orientation, younger block rotations during strike-slip faulting cannot be excluded. The previous D2-event presumably also had an effect on compression at the northern Patagonia margin that was interpreted as result of Patagonia's late Palaeozoic collision with the southwestern Gondwana margin. With the recently proposed Carboniferous subduction and collision south of the North Patagonian Massif, the entire scenario might suggest that Patagonia consists of two different pieces that were amalgamated with southwestern Gondwana during Late Palaeozoic times.

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Shaburova, Yu, N. Shaburova et I. Pashkeev. « THE CHROMIUM AND VANADIUM DISTRIBUTION IN THE DIFFUSION LAYER OF STEEL X35CRNI2-3 DURING THERMОDIFFUSION SATURATION ». Bulletin of the South Ural State University Series ‘Metallurgy’ 22, n^o 1 (2022) : 13–23. http://dx.doi.org/10.14529/met220102.

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Termodiffusion saturation of the surface of alloys with two or more elements remains poorly understood despite the great practical and scientific interest that this method of chemical-thermal treatment represents. The simultaneous introduction of several elements can significantly reduce the processing time of products and obtain a multiphase composition on the surface of the product, which opens up wide opportunities for imparting unique technological and operational properties to products. The article describes the features of the distribution of chromium and vanadium during joint thermal diffusion saturation of steel X35CrNi2-3 at a temperature of 1000 °C. The proposed analysis technique is based on the possibilities of X-ray spectral microanalysis of diffusion layers on transverse microsections of the obtained samples. The elemental composition of the diffusion layer was monitored using a JEOL JSM-6460 LV universal scanning electron microscope. The microstructure was studied on an optical metallographic microscope Axio Observer D1.m. X-ray phase analysis was carried out on a Rigaku Ultima IV diffractometer. The hardness measurement was carried out on an FM-800 microhardness tester at a load of 100 g. Data were obtained on the qualitative and quantitative distribution of chromium and vanadium in the surface layer of steel. It is shown that the emerging diffusion coating has the following structure: a structureless outer layer, consisting mainly of chromium, vanadium carbides → a region of columnar crystals (experiencing γ→α transformation upon cooling), consisting mainly of their Cr1.0V0.4Fe0.3 solid solution → partially decarburized α-phase → base metal. The diffusion coefficients of chromium and vanadium are determined: in the α-phase DCr = 1.3·10–15 m2/s; DV = 1.8·10–14 m2/s; in the γ-phase DCr = 1.13·10–15 m2/s; DV = 1.3·10–15 m2/s. The microhardness of the outer surface layer was 1400–1980 H, the diffusion layer in the base metal was 630–790 HV, and the base metal was about 540–510 HV.

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Miller, E. L., S. M. Katkov, A. Strickland, J. Toro, V. V. Akinin et T. A. Dumitru. « Geochronology and thermochronology of Cretaceous plutons and metamorphic country rocks, Anyui-Chukotka fold belt, North East Arctic Russia ». Stephan Mueller Special Publication Series 4 (17 septembre 2009) : 157–75. http://dx.doi.org/10.5194/smsps-4-157-2009.

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Abstract. U-Pb isotopic dating of seven granitoid plutons and associated intrusions from the Bilibino region (Arctic Chukotka, Russia) was carried out using the SHRIMP-RG. The crystallization ages of these granitoids, which range from approximately 116.9±2.5 to 108.5±2.7 Ma, bracket two regionally significant deformational events. The plutons cut folds, steep foliations and thrust-related structures related to sub-horizontal shortening at lower greenschist facies conditions (D1), believed to be the result of the collision of the Arctic Alaska-Chukotka microplate with Eurasia along the South Anyui Zone (SAZ). Deformation began in the Late Jurassic, based on fossil ages of syn-orogenic clastic strata, and involves strata as young as early Cretaceous (Valanginian) north of Bilibino and as young as Hauterivian-Barremian, in the SAZ. The second phase of deformation (D2) is developed across a broad region around and to the east of the Lupveem batholith of the Alarmaut massif and is interpreted to be coeval with magmatism. D2 formed gently-dipping, high-strain foliations (S2). Growth of biotite, muscovite and actinolite define S2 adjacent to the batholith, while chlorite and white mica define S2 away from the batholith. Sillimanite (± andalusite) at the southeastern edge the Lupveem batholith represent the highest grade metamorphic minerals associated with D2. D2 is interpreted to have developed during regional extension and crustal thinning. Extension directions as measured by stretching lineations, quartz veins, boudinaged quartz veins is NE-SW to NW-SE. Mapped dikes associated with the plutons trend mostly NW-SE and indicate NE-SW directed extension. 40Ar/39Ar ages from S2 micas range from 109.3±1.2 to 103.0±1.8 Ma and are interpreted as post-crystallization cooling ages following a protracted period of magmatism and high heat flow. Regional uplift and erosion of many kilometers of cover produced a subdued erosional surface prior to the eruption of volcanic rocks of the Okhotsk-Chukotka volcanic belt (OCVB) whose basal units (~87 Ma) overlie this profound regional unconformity. A single fission track age on apatite from granite in the Alarmaut massif yielded an age of 90±11 Ma, in good agreement with this inference.

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Кобалава, Галина Олександрівна. « ВИЗНАЧЕННЯ КОНСТРУКТИВНИХ ПАРАМЕТРІВ ПРОТОЧНОЇ ЧАСТИНИ АЕРОТЕРМОПРЕСОРА СИСТЕМИ ОХОЛОДЖЕННЯ ЦИКЛОВОГО ПОВІТРЯ МІКРОТУРБІН ». Aerospace technic and technology, n^o 2 (22 avril 2019) : 44–50. http://dx.doi.org/10.32620/aktt.2019.2.05.

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Among modern jet technologies, one of the promising research areas is a study of gas-dynamic processes in the aerothermopressor. This jet apparatus is a device for contact cooling (the heat from the air flow is consumed for the instantaneous evaporation of water droplets), in which there is a thermogasdynamic compression effect, and that is, the air pressure increase is taken place. A significant influence on the working processes in the aerothermopressor is exercised by design factors. The influence of these factors on energy costs to overcome the friction losses and local resistances on the convergent-divergent sections of the apparatus was investigated. Relevant in the aerothermopressors development is to determinate of rational parameters of the workflow organization with the corresponding development of the flow part design. At the same time, it is necessary to have an opportunity for analytical determination of pressure losses in the confuser and diffuser of the aerothermopressor. A research of typical models of the aerothermopressor for a number of taper angles of a confuser a (convergent angle a = 30; 35; 40; 45; 50 °) and diffuser b (divergent angle b = 6; 8; 10; 12 °), for a number of air velocity values in the working chamber M = 0.4-0.8 has been carried out. The obtained calculated data (results of computer CFD-simulation) and experimental data have been compared. The error of the values for the coefficients of local resistances in the confuser and diffuser does not exceed 7-10%. It was established that the value of the local resistance coefficient depends only on the geometrical parameters (the angle of tapering and the diameters ratio of the input and output D1/D2), that is, the air flow character in the aerothermopressor corresponds to the self-similar mode. The recommended angles were determined: confuser convergent angle a = 30 ° and diffuser divergent angle b = 6 °, corresponding to the minimum pressure loss DPloss = 1.0–9.5 %. The empirical equations were defined for determining the local resistance coefficients of the confuser and diffuser, which can be recommended for use in the design of low-flow aerothermopressor for microturbines

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BOZKURT, ERDİN. « Extensional v. contractional origin for the southern Menderes shear zone, SW Turkey : tectonic and metamorphic implications ». Geological Magazine 144, n^o 1 (26 octobre 2006) : 191–210. http://dx.doi.org/10.1017/s0016756806002664.

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The southern Menderes Massif in southwest Turkey consists mainly of orthogneisses and overlying Palaeozoic–Middle Paleocene schists and marbles. The contact between the two distinct rock types is almost everywhere structural, herein named the southern Menderes shear zone: a S-facing, high-angle ductile shear zone that separates metamorphic rocks of differing grade. Although there is a consensus that the shear zone was associated with top-to-the-S–SSW shearing and is of Tertiary age, its origin and nature have been highly debated over the last decade. Some claim the contact is a thrust fault, while others have argued for an extensional shear zone. Integration of field and microstructural data (the identification of different fabrics, associated kinematics and overprinting relationships) with fission-track thermochronology and the P–T paths of the rocks above and below the shear zone, supports the conclusion that the southern Menderes shear zone is an extensional shear zone and not a thrust. The data are consistent with a model that the exhumation and cooling of the southern Menderes Massif occurred after a period of extensional deformation. Pervasive top-to-the-N–NNE high-temperature–medium-pressure ductile shear structures (D2 deformation) overprint an early HP event (D1 deformation). The subsequent top-to-the-S–SSW greenschist shear band foliation (D3 deformation) developed mostly around the orthogniess–schist contact and forms the most characteristic features of the massif. The top-to-the-N–NNE structures are attributed to the main Alpine constructional deformation that developed during back-thrusting of the Lycian nappes during the latest Palaeogene collision between the Sakarya continent and the Anatolide-Tauride platform across the Neotethyan Ocean. The top-to-the-S–SSW structures are interpreted to be the result of the exhumation of the massif during the activity of the southern Menderes shear zone. The presence of these two distinct fabrics with differing kinematics suggests that the southern Menderes shear zone operated as a top-to-the-N–NNE thrust fault during early Alpine contractional deformation but was later reactivated with an opposite sense of movement (top-to-the-S–SSW) during subsequent Oligocene–Miocene extensional collapse.

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Li, Jiuqing, Yong Qin, Yilin Chen et Jian Shen. « Microstructural Characteristics of Graphite Microcrystals in Graphitized Coal : Insights from Petrology, Mineralogy and Spectroscopy ». Minerals 12, n^o 10 (22 septembre 2022) : 1189. http://dx.doi.org/10.3390/min12101189.

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Graphite microcrystals are the product of coal graphitization and widely exist in the graphitized coal of Yongan Coalfield, Fujian Province, China, which is direct mineralogical evidence for the transformation of coal to graphite. Optical microscopy, scanning electron microscopy (SEM) and micro-Raman spectroscopy were used to detect the morphology and microstructure of the in situ graphite microcrystals. The results show that the volume proportion of graphite microcrystals in graphitized coal samples is between 2.39% and 7.32%, and the optical anisotropy of graphite microcrystals is stronger than that of coal macerals. Graphite microcrystals show the occurrence of attached microcrack inner walls or infilling the cell cavity, with several forms of flakes, needles or aggregates. Under optical microscopy of polarized light and with a retarder plate of 1λ, graphite microcrystals show the color of primary yellow and secondary blue, and the two kinds of colors appear alternately when the microscope is rotating. Additionally, flake-like graphite microcrystals with an isochromatic zone diameter of 10−50 μm are the most widely distributed in graphitized coal. Under SEM, graphite microcrystals show a rough and irregular edge and are characterized by flow or bubble film structures along with several pores, which is the product of cooling crystallization after the softening and melting of carbon-containing substances. Moreover, flake-like graphite microcrystals developed interlayer pores with a clear outline of loose stacking and were almost entirely composed of pure carbon; a small amount of oxygen is related to oxygen-containing functional groups or structural defects. The micro-Raman spectra of graphite microcrystals in the first-order region are characterized by low-intensity D1 and D2 bands and a high-intensity G band, and the parameters R1 and R2 vary from 0.21–0.39 and 0.60–0.74, respectively. The second-order micro-Raman spectra of graphite microcrystals are characterized by a higher intensity of the 2D1 band and a lower intensity of the other three bands. The parameter R3, derived from the area ratio of the 2D1 band to all the bands in the second-order region, was proposed. The value of R3 ranges between 0.78 and 0.86, and both of them indicate a higher percentage of graphene plane with a highly internal crystallographic structure. Similar to the parameters R1 and R2 in the first-order micro-Raman spectrum, the parameter R3 is an effective parameter to characterize the ordering degree of the microstructure, which may be used to evaluate the graphitization degree of graphitization coal.

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Laumonier, Bernard, Christian Marignac et Philippe Kister. « Polymetamorphism and crustal evolution of the eastern Pyrenees during the Late Carboniferous Variscan orogenesis ». Bulletin de la Société Géologique de France 181, n^o 5 (1 septembre 2010) : 411–28. http://dx.doi.org/10.2113/gssgfbull.181.5.411.

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AbstractAbridged English version. – The Variscan Pyrenean belt (fig. 1) has been for long famous for its Late Carboniferous LP-HT metamorphism, characterised by the prograde succession, in medium grade metapelites, of biotite, cordierite, andalusite and sillimanite, together with staurolite and garnet [Guitard et al., 1996]. However, the discovery of two kyanite generations lead Azambre and Guitard [2001] to propose a polymetamorphic evolution, with an early (MI) and a late (MIII) kyanite-bearing Barrovian stage, preceding and following the main LP-HT stage (MII).Geological settingThe Variscan orogeny in the Pyrenees occurred from Namurian to Early Stephanian (c. 325-300 Ma), following the deposition of thick Ediacarian-Ordovician silico-clastites, Silurian to Early Caboniferous carbonates, and pre-orogenic Mid-Carboniferous flyschs.Two main tectonic events are recorded, each one subdivided into regionally correlated sub-events (phases) (table I), allowing a detailed correlation between tectonics, metamorphism and plutonism. The Namurian to Westphalian D1 event (c. 325-310 Ma) resulted in a S-vergent fold and thrust belt (with 100–150 km of N-S shortening) and the development of the main, sub-horizontal, Sr schistosity (D1c phase), coeval with MI. The Westphalian-Early Stephanian D2 event (310-300 Ma) was more complex. First, a syn-convergence extensional phase (N-vergent backfolds and E-W extension) resulted in the E-directed escape of the upper crust (D2a phase). Then, a renewal of the N-S shortening was marked by large upright anticlines (domes) and narrower synclines, with up to 10 km amplitudes (e.g., the Canigou anticline-Villefranche syncline pair) (D2b phase). Both D2a and D2b were coeval with MII and the emplacement of early granitoid sills and laccoliths (e.g., the Ansignan hypersthene-granite in the Agly Massif). Later on, D2 evolved into a transcurrent regime, with belt-parallel dextral transpression (D2c and D2c phases). D2c was coeval with the main stage of granite emplacement under low-grade conditions, allowing the expression of a conspicuous Mγ contact metamorphism (e.g., Mont-Louis pluton). D2d ended the D2 event, with the development of retrograde dextral-reverse mylonites. The late MIII metamorphic event encompassed D2c and D2d (and possibly D2b).The early MI Barrovian metamorphic eventThe MI Barrovian metamorphic event resulted from the crustal thickening associated with the development of the D1 intra-cratonic wedge. It was of low-grade, with a chlorite-muscovite Sr schistosity, in the part of the belt that was subsequently overprinted by the syn-MII transformation of chlorite into biotite. The only remnants of MI medium-grade conditions are found as early kyanite in the deepest domains of the Castillon, St-Barthélémy, Agly and Aston massifs, being there obliterated under high-grade MII conditions, and in the core of the Canigou anticline (Velmanya, point v in fig. 2), where a relict kyanite-staurolite-anorthite paragenesis is known, shielded by MII cordierite. The reconstructed P-T conditions at the thermal peak of MI are 5 kbar (19 km) and 575oC (fig. 2), implying the existence of a (now eroded) major D1 nappe (≥ 7 km thick).The main MII LP-HT metamorphic eventStructural domes and medium– or high-grade MII zones are broadly coincident, high-grade conditions being only encountered in the core of the Albères massif, the southern Aston Dome and the North-Pyrenean massifs (grading there up to the LP granulite facies) (fig. 1).Subdivisions of the MII eventThe prograde MII metamorphism is essentially syn-D2a, with clear syn-kinematic growth of the medium-grade minerals, and the main regional tectono-metamorphic D2a/MII structure is evidently deformed and strongly folded by the D2b phase: the D2b domes are basically post-metamorphic. However, a detailed examination of the blastesis-deformation relationships shows that staurolite is pre- to-synkinematic for D2a, whereas andalusite is strictly synkinematic (and consequently is often observed shielding the staurolite), cordierite being syn-to post-kinematic and syn-D2b in some instances. This allows a subdivision of the MII event into three stages:– MIIs, pre-to-syn-D2a, characterised by the staurolite-andalusite (And1 without cordierite) association, with development of a staurolite zone grading downwards into an andalusite (St → And1) zone. – MIIa, syn-to post-D2a (but always developed prior to D2b), characterised by the cordierite (Cord1)-andalusite (And2) association (without staurolite), with development of a thin cordierite zone grading downwards into an andalusite (Cord1 → And2) zone. – MIIb, post-D2a and syn-D2b, characterised by a large cordierite (Cord2) zone developed at the expense of an-dalusite (And → Cord2), only found in the core of the D2b anticlines (e.g., the Garonne dome).Thus, although MII is basically pre-D2b, and the MIIs and MIIa medium-grade isogrades are folded, it appears that metamorphism was still active in the cores of the ascending D2b domes (MIIb). Moreover, in the core of some domes, prograde sillimanite is also syn-kinematic of the D2b phase, and the sillimanite-muscovite isograde may obliquely overprint the MIIa isogrades, as in the Canigou dome. This is related to the syn-D2b emplacement of granite sheets (e.g., the Canigou granite) and may be interpreted as an aureola of “regional-contact” metamorphism, noted MIIγ, that was evidently coeval with MIIb, and enhanced its effects.P-T-t path of the MII eventThe P-T-t path of the MII event may be described using the petrogenetic grids of Pattison et al. [2002] and Pattison and Vogl [2005] (fig. 3). From MIIs to MIIb, it records a prograde anti-clockwise path, following a post-MI clockwise exhumation path, with ≥ 7 km eroded (fig. 2B). The MIIs pressure was close to 3 kbar (10–11 km) in the St zone and decreased to 2.5 kbar (9 km) at the MIIa stage (And2 isograde), for an estimated temperature of 540oC (based on the triple point of Holdaway [1971], the thermobarometer of Pattison et al. [2002] and independent fluid inclusion data by Kister et al. [2003]). A further pressure decrease, down to 2 kbar (7 km), and a temperature increase (up to 600oC) is registered in the MIIb cordierite zone in the core of active D2b domes. Except for the cores of the domes, MIIa remained the peak temperature event, and during MIIb pressure remained constant (or was re-increasing in the syncline cores) and temperature was constant or decreasing. At the end of the MII event (MIIb-MIIγ), extreme conditions of c. 4 kbar and 700–730oC are recorded in the deepest parts of the belt, where anatexis, succeeding to a sillimanite-K-feldspar zone, is observed, as in the Albères Massif and some North-Pyrenean Massifs.The MII metamorphism as a syn-tectonic plutono-metamorphic eventBased on the observation of the deep crust outcropping in the North Pyrenean massifs, Vielzeuf [in Guitard et al., 1996] concluded that emplacement of mafic melts in the Carboniferous lower crust was responsible for the MII metamorphism. At the beginning of the process, a regional thermal anomaly is superimposed to the middle crust (MIIs-MIIa), directly reflecting the emplacement of mafic sills in the underlying lower crust (fig. 4A). Heat is transferred conductively and, most likely, advected by the aqueous-carbonic fluids issued from the devolatilising lower crust (fluid inclusion data). Heat advection by melts characterised the end of the MII event, with development of more or less local thermal anomalies: still “regional” (MIIbγ) as in the Garonne dome, or directly liked to sheet-like granite intrusions (MIIγ) as at the bottom of the Mont-Louis pluton (fig. 4B) or at the contact of the Canigou granite (fig. 4C).The late MIII Barrovian metamorphic eventThe MIII event is mainly characterised in the eastern massifs (Albères, Cap de Creus), where a retrogressive kyanite (so-called “hysterogenic” kyanite) is overprinting high-grade assemblages. Although poorly expressed, MIII minerals in these massifs define two zones, with an external chloritoid zone and an internal kyanite-staurolite zone. A MIII chloritoid zone (sillimanite → chloritoid) is also observed in the core of the Canigou dome. Under the kyanite-staurolite equilibrium hypothesis, the peak MIII P-T conditions in the eastern massifs are estimated at 5 kbar and 575oC, that would imply a pressure increase of 1 to 1.5 kbar (4–6 km deepening) starting from the end of MII, associated with a severe temperature decrease of 150oC. Such an overpressure cannot be due to the D2d dextral-inverse mylonites. However, a fluid inclusion study [Kister et al., 2003] demonstrated that the rocks of the Villefranche syncline did register a pressure increase at the D2b stage, i.e., experienced effective downwards displacement during the syncline formation, and it may be estimated that, in the core of the syncline, a depth increase of 7–8 km could have been attained. Now, in the Cap de Creus massif, the highest MIII grade is observed in the core of the D2b Birba syncline, analogous to the Villefranche syncline. Thus, D2b deepening in the syncline cores may have contributed to the pressure increase. An additional increase may have been provided by sedimentary accumulation in an overlying (and now eroded) syn-orogenic basin (fig. 5). While such a process may explain the development of MIII associations in the D2b synclines, it remains to explain its appearance in the anticlines (Albères, Canigou). However, in the same fluid inclusion study referred to just above [Kister et al., 2003], it is demonstrated that, post-dating D2c and the late pluton emplacement, the studied area suffered a severe isobaric temperature drop, allowing the appearance of chloritoid in the Canigou core (fig. 5). A similar explanation may hold for the Albères massif, if it is accepted there that late kyanite and staurolite were not in equilibrium: starting from the peak MII conditions (c. 4 kbar and 650o–700oC), a strong isobaric cooling would have allowed the successive appearance of staurolite and kyanite.Discussion and conclusionTimingThe youngest pre-orogenic flyschs are dated (in the Axial Zone) from the Namurian-Westphalian boundary (315±5 Ma), thus setting a minimal age for D1-MI. On the other hand, in the northern Pyrenean Agly massif, the Ansignan hypersthene-granite, which is coeval with MII, is dated at around 315-305 Ma, and the associated norites, likely testifying for the mafic magmatism at the origin of the heat flux responsible for MII, are themselves dated at c. 315 Ma. Finally, the large syn-D2c (post-MII) granite plutons are all dated at 307±3 Ma (i.e., close to the Westphalian-Stephanian boundary). Taken together (with the possibility of a slight diachronism between the North Pyrenean massifs and the Axial Zone, and, within the Axial Zone, between east and west), these data indicate that the MI-MII transition and the whole D2a–c/MII development took place in a very restricted time interval (c. 10 Ma), in Westphalian to Stephanian times.Crustal rheology and orogenic developmentAt the end of the Namurian crustal subduction (D1-MI), the Pyrenean crust, that had been thickened with at least a doubling of the upper crust thickness, had begun to experience uplift and erosion. This exhumation process rapidly changed from retrograde to prograde (MIIs-MIIa) during the D2a (MII) syn-convergence extensional phase.The D2a sub-event was marked by the development of three interrelated processes: (i) isotherm upwelling, regional stratiform MII metamorphism and partial melting in the middle crust, as a result from the intrusion, in the lower crust, of mafic magmas of mantellic derivation; (ii) thinning of the thickened crust; (iii) first arrival of granite plutons in the middle crust. It is thought, according to Vielzeuf [inGuitard et al., 1996], that these processes were initiated by a lithospheric delamination process.At the end of D2a, the crustal rheology had been modified, with a partially melted middle crust that received granitic melts issued from the melting of the lower crust. This highly ductile middle crust was sandwiched between a thick (≥ 10 km) rigid upper crust and a less ductile granulitised hot lower crust (800o–900oC), thus allowing the progressive decoupling of the upper and lower crust from D2a to D2c. The buckling of the upper crust, with formation of the large upright D2b folds, became therefore possible, forcing the injection of deep anatectic melts in the anticline cores (a probable explanation of the MIIbγ thermal culmination), and creating, in the deepened syncline cores, the strong pressure increase that favoured MIII inception.However, the MII isogrades are frozen in their folded position, indicating that cooling of the belt had indeed begun since at least the end of the D2b phase. The cooling was sufficiently rapid to be expressed in the Axial Zone by a sub-isobaric temperature decrease, at the origin of the MIII Barrovian and retrograde event, coeval with the late D2c and D2d phases. In the North Pyrenean Massifs, where the D2d phase was extensive, the retrograde MIII event could not be expressed, due to both decompression and thermal effects of the extension.A summary of this complex evolution is given in figure 6. Finally, the interrelated D2 and MII events appear as the record, in the middle-upper crust, of a very short, but very intense heating event that strongly modified the rheologic behaviour of the crust inherited from the D1 crustal subduction and allowed a transitory decoupling of the upper and lower crust. The isobaric MIII event records an exceptionally rapid return to the “normal” thermal and rheologic structures of the crust.The rapidly changing tectonic and thermal conditions that characterise the Variscan Pyrenees during the D2 event may be understood if the position of the Pyrenees within the southern branch of the West European Variscan belt is considered (fig. 7).

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Morquecho, Lourdes, Ismael Gárate-Lizárraga et Haifeng Gu. « Morphological and molecular characterization of the genus Coolia (Dinophyceae) from Bahía de La Paz, southwest Gulf of California ». Algae 37, n^o 3 (15 septembre 2022) : 185–204. http://dx.doi.org/10.4490/algae.2022.37.9.2.

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The genus Coolia A. Meunier 1919 has a global distribution and is a common member of epiphytic dinoflagellate assemblages in neritic ecosystems. Coolia monotis is the type species of the genus and was the only known species for 76 years. Over the past few decades, molecular characterization has unveiled two species complexes that group morphologically very similar species, so their limits are often unclear. To provide new knowledge on the biogeography and species composition of the genus Coolia, 16 strains were isolated from Bahía de La Paz, Gulf of California. The species were identified by applying morphological and molecular approaches. The morphometric characteristics of all isolated Coolia species were consistent with the original taxa descriptions. Phylogenetic analyses (large subunit [LSU] rDNA D1 / D2 and internal transcribed spacer [ITS] 1 / 5.8S / ITS2) revealed a species assemblage comprising Coolia malayensis, C. palmyrensis, C. tropicalis, and the C. cf. canariensis lineage. This is the first report of Coolia palmyrensis and C. cf. canariensis in Mexico and C. tropicalis in the Gulf of California. Our results strengthen the biogeographical understanding of these potentially harmful epiphytic dinoflagellate species.

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Zhou, Tao, Can Hui Sun et Wan Xu Cheng. « Study on Thermal Characteristics of Water-Rod in SCWR ». Advanced Materials Research 512-515 (mai 2012) : 869–73. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.869.

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Water-rod is introduced into Supercritical Water Cooled Reactor (SCWR) to guarantee the homogeneous distribution of core axial power, and there could be many types of flow in water-rod. Based on three types of water-rod and flow, which named S type, D1 type, and D2 type, choosing different values of structural parameters and material thermal conductivity, the distributions of moderator density and average density in each case are obtained through making program to associated-calculate the fuel rod, coolant and moderator. The results indicate that considering only moderator density, the D2 type double water-rod which has smaller thermal conductivity and bigger outer length of inner water-rod is the best choice; considering average density, both the S type single water-rod and the D2 type double water-rod which have smaller thermal conductivity and smaller outer length of inner water-rod is the best choice; the thermal performance of D1 type double water-rod is inferior because of its inherent defect, so it is not suitable for use.

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Abdennadher, Moufida, Amel Bellaaj Zouari, Walid Medhioub, Antonella Penna et Asma Hamza. « Characterization of Coolia spp. (Gonyaucales, Dinophyceae) from Southern Tunisia : first record of Coolia malayensis in the Mediterranean Sea ». Algae 36, n^o 3 (15 septembre 2021) : 175–93. http://dx.doi.org/10.4490/algae.2021.36.6.2.

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This study provides the first report of the presence of Coolia malayensis in the Mediterranean Sea, co-occurring with C. monotis. Isolated strains from the Gulf of Gabès, Tunisia (South-eastern Mediterranean) were identified by morphological characterization and phylogenetic analysis. Examination by light and scanning electron microscopy revealed no significant morphological differences between the Tunisian isolates and other geographically distant strains of C. monotis and C. malayensis. Phylogenetic trees based on ITS1-5.8S-ITS2 and D1‒D3/28S rDNA sequences showed that C. monotis strains clustered with others from the Mediterranean and Atlantic whereas the C. malayensis isolate branched with isolates from the Pacific and the Atlantic, therefore revealing no geographical trend among C. monotis and C. malayensis populations. Ultrastructural analyses by transmission electron microscopy revealed the presence of numerous vesicles containing spirally coiled ﬁbers in both C. malayensis and C. monotis cells, which we speculate to be involved in mucus production.

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de Queiroz Mendes, Maria Cristina, José Marcos de Castro Nunes, Santiago Fraga, Francisco Rodríguez, José Mariano Franco, Pilar Riobó, Suema Branco et Mariângela Menezes. « Morphology, molecular phylogeny and toxinology of Coolia and Prorocentrum strains isolated from the tropical South Western Atlantic Ocean ». Botanica Marina 62, n^o 2 (24 avril 2019) : 125–40. http://dx.doi.org/10.1515/bot-2018-0053.

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Abstract The morphology, molecular phylogeny and toxinology of two Coolia and one Prorocentrum dinoflagellate strains from Brazil were characterized. They matched with Coolia malayensis and Coolia tropicalis morphotypes, while the Prorocentrum strain fitted well with the morphology of Prorocentrum emarginatum. Complementary identification by molecular analyses was carried out based on LSU and ITS-5.8S rDNA. Phylogenetic analyses of Coolia strains (D1/D2 region, LSU rDNA), showed that C. malayensis (strain UFBA044) segregated together with sequences of this species from other parts of the world, but diverged earlier in a separate branch to sequences from São Paulo (Brazil) or Caribbean areas. Coolia tropicalis (strain UFBA055) grouped with other sequences of this species, in a subclade with an isolate from Belize, closer to a subgroup including isolates from Thailand, Australia and Hong Kong. Phylogenetic analyses (ITS-5.8S rDNA) of P. emarginatum (strain UFBA033) grouped together with another sequence of this species from China Sea. Diarrhetic shellfish poisoning toxins (OA, DTXs and PTX2) were not detected in P. emarginatum by mass spectrometry analyses. However, hemolytic assays in P. emarginatum and both Coolia strains in this study showed positive results.

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Tibiriçá, Carlos Eduardo Junqueira de Azevedo, Manoella Sibat, Luciano Felício Fernandes, Gwenaël Bilien, Nicolas Chomérat, Philipp Hess et Luiz L. Mafra Jr. « Diversity and Toxicity of the Genus Coolia Meunier in Brazil, and Detection of 44-methyl Gambierone in Coolia tropicalis ». Toxins 12, n^o 5 (15 mai 2020) : 327. http://dx.doi.org/10.3390/toxins12050327.

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Coolia is a genus of marine benthic dinoflagellates which is widely distributed in tropical and temperate zones. Toxicity has been reported in selected Coolia species, although the identity of causative compounds is still controversial. In this study, we investigated the taxonomical and toxicological aspects of Coolia species from Brazil. Since light- and electron microscopy-based morphology was not enough to distinguish small-celled species, ITS and LSU D1-D3 phylogenetic analyses were used for species definition. Cultures of Coolia palmyrensis and Coolia santacroce were established from samples collected along the northeastern Brazilian coast, the first record of both species in South Atlantic waters. Cultures of Coolia malayensis and Coolia tropicalis were also established and exhibited acute in vivo toxicity to adults of Artemia salina, while C. palmyrensis and C. santacroce were non-toxic. The presence of 30 yessotoxin analogues, 7 metabolites of Coolia and 44 Gambierdiscus metabolites was screened in 14 strains of Coolia. 44-methyl gambierone (formerly referred to as MTX3) and a new isomer of this compound were detected only in C. tropicalis, using both low- and high-resolution LC-MS/MS. To our knowledge, this is the first report of gambierone analogues in dinoflagellates other than Gambierdiscus; the role of C. tropicalis in ciguatera poisoning thus deserves to be considered in further investigations.

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Furqaranda, Rastra, et Suwarno Suwarno. « Analisa Minyak Isolasi Transformator Daya dengan Metode Disolved Gas Analysis (DGA) dan Purifikasi ». Jurnal Ilmiah Ecosystem 23, n^o 2 (30 août 2023) : 441–49. http://dx.doi.org/10.35965/eco.v23i2.2871.

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Salah satu komponen terpenting dalam sistem pembangkitan listrik yaitu transformator daya. Transformator daya memiliki minyak isolator cair sebagai pendingin maka kualitas minyak merupakan hal yang harus sangat diperhatikan karena memiliki kondisi ketidaknormalan jika terjadinya gangguan panas berlebih pada tansformator daya yang mengakibatkan kebakaran. Metode yang dapat digunakan untuk mengetahui gangguan yang terjadi pada minyak isolasi transformator daya adalah dengan metode pengujian Dissolved Gas Analysis (DGA). Dalam penelitian ini, pengujian DGA menggunakan interpretasi dari IEEE Std C57-104-2008. Tujuan dari metode yang digunakan adalah mencari analisa gangguan ketidaknormalan minyak trafo ialah dengan 4 metode yaitu metode TDCG (Total Dissolved Combustible Gas), Rogers Rasio, Key Gas, dan Duval Triangle. Dari hasil analisa yang dilakukan menunjukkan metode TDCG memiliki kandungan gas 1565 ppm berada pada kondisi 2, metode Rogers Rasio menghasilkan gejala panas berlebih yang mencapai temperature 300-700oC, metode Key Gas menyebabkan gangguan Overheating Oil, dan metode Duval Triangle menghasilkan D1 = Discharge of Low Energy, T2 = Thermal Fault 300-700ºC, dan T3 = Thermal Faults Exceeding 700ºC. Untuk menghilangkan berbagai jenis gangguan gas ketidaknormalan serta memperbaiki kualitas minyak isolasi transformator daya dapat dilakukan dengan menggunakan purifikasi. Dari hasil purifikasi minyak trafo penurunan kandungan gas menjadi 243 ppm berada pada kondisi 1, sehingga kualitas minyak isolasi transformator daya tersebut dalam keadaan murni dan layak untuk digunakan kembali di PT. Perta Arun Gas Lhokseumawe The most important part in a system of electrical is power transformers. The power transformer having oil an insulator liquid as a coolant so qualities of oil is must be very consider, because having the condition abnormality if disruption remains in the heat power transformer resulting in fire. A method that can be used to know the problems that occurred on oil isolation of power transformer by Dissolved Analysis Gas (DGA). In this thesis, testing DGA use interpretation of IEEE Std C57-104-2008. Methods is used to looking for analysis that abnormality disorder a oil transformer is that by 4th methods which is a method of TDGC (Total Dissolved Combustible Gas ), Rogers Ratio, Key Gas, and Duval Triangle. From the analysis carried out show TDGC method has any gas 1565 ppm at the 2nd condition, Rogers ratio method of excess produce symptoms heat at temperature 300 – 7000C, Key gas causing disorder overheating oil , and duval triangel methods produce D1 = discharge of low energy, T2 = thermal fault 300- 7000C , and T3 = thermal faults exceeding 7000C. To deprive of various types of disorder that abnormality gas and to improve quality of an insulating transformer power can be conducted using purifikasi. From the results of purifikasi oil transformer the decline in the womb a gas into 243 ppm in 1st condition, resulting in the isolation oil transformer resources in a pure state and useful for used of the back in PT. Perta Arun Gas Lhokseumawe

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Innes, Andrew, Prosenjit Majumder, Heung-Ryoul Noh et S. L. Cornish. « Modulation transfer spectroscopy of the D1 transition of potassium : theory and experiment ». Journal of Physics B : Atomic, Molecular and Optical Physics, 8 mars 2024. http://dx.doi.org/10.1088/1361-6455/ad31af.

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Abstract We report on a study of modulation transfer spectroscopy of the 4S1/2 → 4P1/2 (D1) transitionof naturally abundant potassium in a room-temperature vapour cell. This transition is critical forlaser cooling and optical pumping of potassium and our study is therefore motivated by the need forrobust laser frequency stabilisation. Despite the absence of a closed transition, the small ground-state hyperfine splitting in potassium results in strong crossover features in the D1 modulationtransfer spectrum. To emphasise this we compare the D1 and D2 spectra of potassium with thoseof rubidium. Further, we compare our experimental results with a detailed theoretical simulation,examining different pump-probe polarization configurations to identify the optimal signals for laserfrequency stabilisation. We find good agreement between the experiment and the theory, especiallyfor the lin ∥ lin polarization configuration.

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Liang, Jintong, Sibing Liu, Luping Li, Jie Dai, Xiaotian Li et Chuanlong Mou. « Geochemical Constraints on the Hydrothermal Dolomitization of the Middle-Upper Cambrian Xixiangchi Formation in the Sichuan Basin, China ». Frontiers in Earth Science 10 (16 juin 2022). http://dx.doi.org/10.3389/feart.2022.927066.

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The Middle-Upper Cambrian Xixiangchi carbonates in the Sichuan Basin have been pervasively dolomitized. In the presented work, petrographic investigation revealed three generations of the Xixiangchi dolomites, consisting of dolomicrite (D1, 5–20 μm) with a planar-s to non-planar texture, fabric destructive dolomite (D2, 50–150 μM) with a planar-s to planar-e texture, and saddle dolomite (D3, 300 μm to 4 mm) with a planar-s to planar-e texture. D1 and D2 dolomites are presented as matrix dolomites, whereas D3 dolomites are observed as fracture-filling dolomites. Compared with the matrix D1 and D2 dolomites, which are interpreted as products of dolomitization under near-surface or at shallow burial conditions, the depleted δ13C and δ18O values of D3 than D1 and D2 dolomites are probably caused by the temperature-controlled isotopic fractionation within an increasing fluid–rock interaction at burial. The enriched Mn, Sr, and Ba concentrations of D3 than D1 and D2 dolomites suggest a newly introduced type of diagenetic fluids, which is probably related to the upwelling of magmatic activities (Emeishan large igneous province). By contrast, the abnormally depleted Fe concentration in D3 dolomites is attributed to its preferential incorporation into other solid phases rather than its true concentration. The similar rare earth element (REE) partition patterns of D1 and D2 dolomites demonstrate similar dolomitization fluids related to seawater or marine-origin fluids. The hydrothermal-derived D3 dolomites exhibit a different REE partition pattern by contrast. The negative Eu anomalies of D3 dolomites may represent hydrothermal fluid cooling or an association with intermediate-felsic igneous rocks. The findings of the presented work would enhance our understanding on the hydrothermal dolomitization of the Middle-Upper Cambrian Xixiangchi Formation.

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Barker, Daniel, Peter Elgee, Ananya Sitaram, Eric Norrgard, Nikolai Klimov, Gretchen K. Campbell et Stephen Eckel. « Grating magneto-optical traps with complicated level structures ». New Journal of Physics, 13 octobre 2023. http://dx.doi.org/10.1088/1367-2630/ad02ea.

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Abstract We study the forces and optical pumping within grating magneto-optical traps (MOTs) operating on transitions with non-trivial level structure. In contrast to the standard six-beam MOT configuration, rate equation modelling predicts that the asymmetric laser geometry of a grating MOT will produce spin-polarized atomic samples. Furthermore, the Landé g-factors and total angular momenta of the trapping transition strongly influence both the confinement and position of the trap. Using the intuition gained from the rate equation model, we realize a grating MOT of fermionic 87Sr and observe that it forms closer to the center of the trap's quadrupole magnetic field than its bosonic counterpart. We also explore the application of grating MOTs to molecule laser cooling, where the rate equations suggest that two-color operation is necessary, but not sufficient, for stable confinement for type-II level structures. To test our molecule laser cooling models, we create grating MOTs using the D1 line of 7Li and see that only two of the four possible six-beam polarization configurations operate in the grating geometry. Our results will aid the development of portable atom and molecule traps for time keeping, inertial navigation, and precision measurement.

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Rajan, K. M., Ashok Kumar Sahoo, Bharat Chandra Routara et Ramanuj Kumar. « Investigation on surface roughness, tool wear and cutting power in MQL turning of bio-medical Ti-6Al-4V ELI alloy with sustainability ». Proceedings of the Institution of Mechanical Engineers, Part E : Journal of Process Mechanical Engineering, 13 décembre 2021, 095440892110637. http://dx.doi.org/10.1177/09544089211063712.

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Ti-6Al-4V ELI (Grade 23) is highly recommended for bio-materials and due to its low thermal conductivity and chemically reactive properties, machinability is poor. Thus the current work emphasized on the selection of appropriate cooling technique and optimal cutting parameters for machining of Ti-6Al-4V ELI alloy with sustainability analysis for surface roughness, flank wear and cutting power. Initially, the cutting performances under dry, flood and MQL environments are compared and MQL is observed to better performed. At lower speed (70 m/min), MQL exhibited 26.38% and 19.69% lesser surface roughness relative to dry and flood cooling individually. At the same cutting condition, MQL assisted cutting resulted in lower flank wear relative to dry (157. 33%) and flood cooling (40%). Further, a detailed investigation has been made under MQL through Taguchi L18 design of experiments. The major mechanisms for flank wear are found to be abrasion, chipping and notch wear. Optimal data set through Grey relational analysis is found to be v1 (70 m/min), f1 (0.1 mm/rev) and d1 (0.1 mm) and improved. Quadratic regression model is found to be significant for prediction of responses. Sustainability Pugh matrix assessment revealed that MQL environment enhanced the economical, technological as well as environmental and operator health aspects. Reduction of energy consumption by 53.96% and savings of carbon footprints by 68.46 kg of CO2 observed under MQL at optimal conditions and thus saves manufacturing cost.

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Bocheński, Mateusz, et Mariusz Semczuk. « Sub-Doppler laser cooling and magnetic trapping of natural-abundance fermionic potassium. » Journal of Physics B : Atomic, Molecular and Optical Physics, 23 janvier 2024. http://dx.doi.org/10.1088/1361-6455/ad2181.

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Abstract We demonstrate the largest number of 40K atoms that has ever been cooled to deeply sub-Doppler temperatures in a single chamber apparatus without using an enriched source of potassium. With gray molasses cooling on the D1-line following a standard D2-line magneto-optical trap, we obtain 3×105 atoms at 10(2) μK. We reach densities high enough to measure the temperature via absorption imaging using the time-of-flight method. We magnetically trap a mixture of mF=-3/2,-5/2 and -7/2 Zeeman states of the F=7/2 hyperfine ground state confining 5×104 atoms with a lifetime of 0.6 s or ∼103 atoms with a lifetime of 2.8 s - depending on whether the temperature of the potassium dispensers was chosen to maximize the atom number or the lifetime. The background pressure-limited lifetime of 0.6 s is a reasonable starting point for proof-of-principle experiments with atoms and/or molecules in optical tweezers as well as for sympathetic cooling with another species if transport to a secondary chamber is implemented.Our results show that unenriched potassium can be used to optimize experimental setups containing 40K in the initial stages of their construction, which can effectively extend the lifetime of enriched sources needed for proper experiments. Moreover, demonstration of sub-Doppler cooling and magnetic trapping of a relatively small number of potassium atoms might influence experiments with laser cooled radioactive isotopes of potassium.

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Fréville, Kévin, Pierre Trap, Jonas Vanardois, Jérémie Melleton, Michel Faure, Olivier Bruguier, Marc Poujol et Phillipe Lach. « Carboniferous tectono-metamorphic evolution of the Variscan crust in the Belledonne-Pelvoux area. » BSGF - Earth Sciences Bulletin, 23 mai 2022. http://dx.doi.org/10.1051/bsgf/2022008.

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Based on new structural, petrological and U-Th-Pb data, a reappraisal of the Variscan tectono-metamorphic history of the SW Belledonne-Pelvoux (Eastern Cristalline Massifs, French Alps) mid-lower crust is proposed. These results are keys to better understand the flow pattern of the variscan partially molten crust and the geodynamic evolution of the sub-meridional branch of the variscan belt. The SW Belledonne area exposes the suprastructure where the medium grade metamorphic rocks record a middle Carboniferous evolution, with a westward gently dipping S1 foliation refolded by east-verging inclined folds (F2) with a subvertical to west-dipping axial plane cleavage S2. Further east, in the Pelvoux area, the high-grade metamorphic rocks of the infrastructure, mostly migmatites, record a prominent D2 deformation with a penetrative NE-SW steeply dipping S2 foliation and a network of NS and NW-SE trending shear zones the kinematics of which indicate a bulk sinistral transpression. D1 and D2 features are interpreted as reflecting a NW–SE contraction, first marked by dominant nappe stacking and subsequently overprinted by transpressional shearing. The supra/infrastructure boundary is typified by a D3 deformation zone that consists of a flat laying S3 foliation with a NW-SE stretching lineation along which top to NW sense of shear is observed. The D1 event corresponds to mid-carboniferous crustal thickening. Exhumation of deep-seated rocks during the transpressional D2 event followed a near isothermal (ca. 700 °C) evolution down to pressure of ca. 5kbar in the period 325-306 Ma. From ca. 306 Ma, D2 and D3 acted synchronously while the mid-lower crust recorded a near isobaric temperature increase up to 850 °C before final cooling and retrogression. The P-T-t history of the Pelvoux area is very similar to the nearby Velay dome and suggest that the Belledonne-Pelvoux area may belong to the Western Moldanubian zone of the Variscan Belt. In that vision, we suggest that coupling between D2 and D3 deformation enable the south-eastward migration, i.e. from the orogenic plateau to the foreland, of the hot and low-viscosity partially-molten crust.

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M. Sahar, Amirah, et A. I. M. Shaiful. « NUMERICAL STUDY OF THE EFFECT OF AREA OF MANIFOLD AND INLET/OUTLET FLOW ARRANGEMENT 0N FLOW DISTRIBUTION IN PARALLEL RECTANGULAR MICROCHANNEL COOLING SYSTEM ». Jurnal Teknologi 79, n^o 7-3 (20 novembre 2017). http://dx.doi.org/10.11113/jt.v79.11901.

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Parallel microchannels have been widely used in cooling of compact electronic equipment due to large contact area with liquid and availability of large mass of fluid to carry away heat. However, understanding of flow distribution for microchannel parallel system is still unclear and there still lack of studies give a clear pictures to understand the complex flow features which cause the flow maldistribution. Generally, the geometrical structure of the manifold and micro channels play an important role in flow distribution between micro channels, which might affects the heat and mass transfer efficiency, even the performance of micro exchangers. A practical design of exchanger basically involves the selection of an optimized solution, keeping an optimal balance between gain in heat transfer and pressure drop penalty. A parallel microchannels configurations consisting inlet and outlet rectangular manifold were simulated to study flow distribution among the channels were investigated numerically by using Ansys Fluent 14.5. The numerical results was validated using existing experimental data and showed a similar trend with values 1% higher than experimental data. The influence of inlet/outlet manifold area and inlet/outlet arrangement on flow distribution in channels were carried out in this study. Based on the predicted flow non-uniformity value, 𝜙, Z- type flow arrangement exhibits higher value of 𝜙, which is 8%, followed by U-type, 2.6% and the I-type, 2.49%. Thus, a better uniformity of velocity and temperature distributions can be achieved in I-shape flow arrangement. The behavior of the flow distributions inside channels is due to the vortices that occurred at manifold. Besides comparing the pressure drop for case 1(D1) and case 2(D2), it is worth to mention that, as the area of inlet and outlet manifold decrease by 50%, the pressure drop is increasing about 5%. However, the inlet/outlet area of manifold on velocity and fluid temperature distributions was insignificant.

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Corno, Alberto, Chiara Groppo, Pietro Mosca, Alessandro Borghi et Marco Gattiglio. « Eclogitic metamorphism in the Alpine far-west : petrological constraints on the Banchetta-Rognosa tectonic unit (Val Troncea, Western Alps) ». Swiss Journal of Geosciences 114, n^o 1 (16 septembre 2021). http://dx.doi.org/10.1186/s00015-021-00393-7.

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AbstractThe Banchetta-Rognosa tectonic unit (BRU), covering an area of 10 km2 in the upper Chisone valley, consists of two successions referred to a continental margin (Monte Banchetta succession) and a proximal oceanic domain (Punta Rognosa succession) respectively. In both successions, Mesozoic meta-sedimentary covers discordantly lie on their basement. This paper presents new data on the lithostratigraphy and the metamorphic evolution of the continental basement of the Monte Banchetta succession. It comprises two meta-sedimentary sequences with minor meta-intrusive bodies preserving their original lithostratigraphic configuration, despite the intense Alpine deformation and metamorphic re-equilibration. Phase equilibrium modeling points to a metamorphic eclogitic peak (D1 event) of 20–23 kbar and 440–500 °C, consistent among three different samples, analyzed from suitable lithologies. The exhumation P–T path is characterized by a first decompression of at least 10 kbar, leading to the development of the main regional foliation (i.e. tectono-metamorphic event D2). The subsequent exhumation stage (D3 event) is marked by a further decompression of almost 7–8 kbar associated with a significant temperature decrease (cooling down to 350–400 °C), implying a geothermal gradient compatible with a continental collision regime. These data infer for this unit higher peak P–T conditions than previously estimated with conventional thermobarometry. The comparison of our results with the peak P–T conditions registered by other neighboring tectonic units allows to interpret the BRU as one of the westernmost eclogite-facies unit in the Alps.

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Djoumaliisky, Strashimir, Maria Cerrada, Tatyana Dobreva et Peter Zipper. « Development of β and α isotactic polypropylene polymorphs in injection molded structural foams ». Chemical Papers 64, n^o 2 (1 janvier 2010). http://dx.doi.org/10.2478/s11696-009-0107-6.

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AbstractStructural foam moldings, composed of three co-axial cylinders differing in diameter (10 mm, 20 mm, and 30 mm) and length, were produced from isotactic polypropylene (PP) and 0.5 mass % 1,1′-azobisformamide on an in-line injection molding machine in a mould cavity pre-pressurized with nitrogen by the classical low-pressure process combined with egression of foamed melt from the core. Injection-molding conditions were as follows: melt temperature, 220°C, mold temperature, 20°C, cooling time, 5 min, gas-counter pressure, 0.5 MPa. The sprue gate was at the end of the smallest cylinder and its diameter was varied from 4 mm to 7 mm. To investigate the development of β-PP modification in terms of phenomena due to the phase change in the mould cavity (expansion), appropriate specimens (cross-sections) were cut from the middle of each cylinder in parallel and perpendicular orientation to the flow direction and were investigated by WAXS, DSC, and POM. As revealed by WAXS, β-PP is present in all cylinders, always concentrated in certain regions of the cross-section — mainly in the surface layers of the smallest cylinder (D1) and in the foamed core of the other two cylinders (D2 and D3). Its concentration was found to change with the sprue dimensions. High β-PP concentration is associated with a preferred orientation in the skin of the smallest cylinder and with better expansion conditions in larger cylinders. Presence of the β-phase in the surface layers and in the core of the moldings was proved by DSC and POM.

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Walker, Mary E., Sean D. Kodani, Hebe Agustina Mena, Yu-Hua Tseng, Aaron M. Cypess et Matthew Spite. « Brown adipose tissue activation in humans increases plasma levels of lipid mediators ». Journal of Clinical Endocrinology & ; Metabolism, 10 janvier 2024. http://dx.doi.org/10.1210/clinem/dgae016.

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Abstract Context Activation of brown adipose tissue (BAT) thermogenesis improves insulin sensitivity and is beneficial in obesity. Emerging evidence indicates that BAT activation increases lipid mediators that play autocrine and endocrine roles to regulate metabolism and inflammation. Objective The goal of the study was to determine the relationship between two distinct approaches of BAT activation (cold exposure and mirabegron treatment) with lipid mediators in humans. Methods Healthy female subjects (n = 14) were treated with β3-adrenergic receptor agonist mirabegron (100 mg) daily for 28 days. A subset of female subjects (n = 8) was additionally exposed to cold temperatures (14-16°C) for 2 hours using a cooling vest prior to initiating mirabegron treatment. Main Outcome Measures A panel of lipid mediators was assessed in plasma using targeted liquid chromatography-tandem mass spectrometry, and their relationship to anthropometric and metabolic parameters was determined. Results Activation of BAT with cold exposure acutely increased levels of lipoxygenase and cyclooxygenase products, including 12-hydroxyeicosapentaenoic acid (HEPE), 12-hydroxyeicosatetraenoic acid (HETE), 5-HETE, 14-hydroxydocosahexaenoic acid (HDHA), an isomer of maresin 2 (MaR2), 17-HDHA, protectin D1 (PD1), and prostaglandin E2 (PGE2). Mirabegron treatment similarly increased these products acutely, although levels of some mediators were blunted after chronic mirabegron treatment. Selected lipid mediators, including a MaR2 isomer, 17-HDHA, 5-HETE, and 15-HETE, positively correlated with non-esterified fatty acids and negatively correlated with the respiratory quotient, while PD1, 15-HETE, and 5-HETE positively correlated with adiponectin. Conclusion These results indicate that selected lipid mediators may serve as biomarkers of BAT activation.

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Liang, Cangjuan, Ping Wang, Zehan Wang, Na Zhao, Xuemei Li, Jingyu Li, Lirong Zhang, Qingfang Meng et Hongfei Yan. « Puccinia suaveolens Causing Leaf Rust on Cirsium setosum in China ». Plant Disease, 4 janvier 2024. http://dx.doi.org/10.1094/pdis-11-23-2368-pdn.

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Thistle, Cirsium setosum (Willd.) M. Bieb., is widely distributed in China as a common weed in fields. It is also used as a traditional Chinese medicine for cooling blood, stopping bleeding, dispelling stasis, detoxifying, and resolving carbuncle. In 2023, we found a rust disease on plants of Cirsium setosum in the experimental field of Hebei Agricultural University, Baoding, Hebei Province, China, with incidence of 15% - 25% (Fig. S1 A, B). The diseased leaves turned yellow, and the leaf edges were slightly rolled. The yellow, oil-like pycnia and pycniospores covered the baxial surface of leaves, and brown pustules were produced after 2-3 weeks. On the adaxial surface of the leaves, the brown rust pustules were mainly along the leaf veins. Stems were also be infected later, and dark pustules were scattered. The diseased plants were relatively short and small, and produced relatively small or no flowers compared to healthy plants. A total of 100 plants with typical leaf rust symptoms and signs were collected. To confirm the pathogenicity, healthy plants of thistle were sprayed with 5 ml of urediospores suspension (2.6×105/ml), and plants sprayed with sterile distilled water were treated as control. The sprayed plants were incubated under high moist conditions at 18°C for 24 h, and the inoculated plants were grown at 20°C in a greenhouse. Ten days after inoculation, the plants inoculated with urediniospores showed rust symptoms with uredinia and urediniospores on the leaves (Fig. S1 C), while the control plants were healthy. For morphological characterization, urediospores were picked from the naturally infected plants and placed in a drop of sterile water on a glass slide using a sterile needle, and observed and measured under a microscope. Urediospores were nearly spherical, brown-yellow, and measured 15 - 25 μm in diameter (n=100) (Fig. S1 D). Telia were scattered on the baxial surface of the naturally infected leaves, and teliospores were oval, yellow-brown, double-celled, with very short hyaline pedicels, and measured 15-20 × 15-30 μm (n=100) (Fig. S1 E). For molecular characterization, about 200 μg of urediniospores was collected and placed in a 1.5 ml sterile centrifuge tube, and genomic DNA was extracted using the cetyl-trimethylammonium bromide method (Gawel et al. 1991). The internal transcribed spacer (ITS) region of the rDNA and the D1/D2 domain were amplified using primer pairs ITS1/ITS4 (White et al. 1990) and NL1/NL4 (Borhani et al. 2013) in polymerase chain reaction (PCR), respectively. The PCR products were sequenced, and their sequences were aligned and compared with those deposited in GenBank. The obtained sequences were deposited in GenBank (OR600240 for ITS and OR598614 for D1/D2), which were 100% identical with 100% coverage to the ITS sequence (ON063373.1) and the D1/D2 sequence (ON063379.1) of Puccinia suaveolens (Menzies 1953). Based on the morphological characteristics and DNA sequences, the isolates were identified as P. suaveolens (Fig. S1 and Fig. S2). Thistle rust caused by Puccinia obtegens has been reported in some other parts of China (Zhang 2012). To the best of our knowledge, this is the first report of P. suaveolens causing leaf rust on C. setosum in China. This discovery is helpful for control of leaf rust on thistle grown for Chines medicine and other purposes, and the rust species could be used for biological control of thistle as a weed in crop fields.

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Yao Koffi, Augustin, Lenka Baratoux, Pavel Pitra, Alain Nicaise Kouamelan, Olivier Vanderhaeghe, Nicolas Thébaud, Olivier Bruguier, Sylvain Block, Hervé Jean-Luc Fossou Kouadio et Jacques Kone. « A tectonic model for the juxtaposition of granulite- and amphibolite-facies rocks in the Eburnean collision in the orogenic belt (Sassandra-Cavally domain, Côte d’Ivoire) ». BSGF - Earth Sciences Bulletin, 1 juin 2023. http://dx.doi.org/10.1051/bsgf/2023007.

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The Sassandra-Cavally (SASCA) domain (SW Côte d’Ivoire) marks the transition between the Archaean Kenema-Man craton and the Palaeoproterozoic (Rhyacian) Baoule-Mossi terranes. It is characterized by the tectonic juxtaposition of granulite-facies and amphibolite-facies rocks. Migmatitic grey gneisses, garnet-cordierite-sillimanite migmatitic paragneisses and garnet-staurolite-bearing micaschists reached peak pressure conditions ranging from ~6.6 kbar at 620°C to ~10 kbar at 820°C. These conditions are associated with the first recorded deformation D1 and correspond to a Barrovian geothermal gradient of ~25°C/km. Subsequent exhumation, associated with a second deformation D2, was marked by decompression followed by cooling along apparent geothermal gradients of ~40°C/km. A D3 deformation phase is marked by folding and local transposition of the regional S1/S2 foliation by E-W trending shear zones. LA-ICP-MS U-Pb dating of monazite, which displays complex internal structures, reveals four age groups as a function of their textural position: 1) Rare relictual zones yield dates at the Archaean-Palaeoproterozoic transition (c. 2400–2600 Ma); 2) a cluster of dates centered at c. 2037 Ma. This cluster includes dates from crystals located in the S2 foliation of the migmatitic grey gneiss, which suggests that this is the age for the D2 exhumation; 3) a cluster of dates centered at c. 2000 Ma, and 4) dates spreading from c. 1978 to 1913 Ma, documented for the first time in the West African Craton monazites. The ages of the latter two groups are similar to the ones identified in the Guiana Shield, and could be attributed to a disturbance by fluids, to a periodic opening of U-Pb system or to an episodic crystallization of monazite during slow cooling lasting several tens of Myrs. These data bring new petro-tectonic and geochronological constraints on the contact between the Rhyacian Baoule-Mossi terrains and the Archaean Kenema-Man nucleus, and confirm the collisional character of the polyphase tectono-metamorphic evolution of the SASCA domain during the Eburnean orogeny. They suggest a transitional regime between the predominance of gravitational instabilities and modern plate tectonics. The exhumation of the granulite- and amphibolite-facies rocks results from a combination of crustal-scale folding associated with lateral flow and regional transcurrent shear zones, which would explain the juxtaposition of rocks that reached significantly different P–T conditions.

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Blair, Nathaniel T., Ana I. Caceres, Ingrid Carvacho, Dipayan Chaudhuri, David E. Clapham, Katrien De Clerq, Markus Delling et al. « Transient Receptor Potential channels (TRP) in GtoPdb v.2023.2 ». IUPHAR/BPS Guide to Pharmacology CITE 2023, n^o 2 (7 août 2023). http://dx.doi.org/10.2218/gtopdb/f78/2023.2.

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The TRP superfamily of channels (nomenclature as agreed by NC-IUPHAR [176, 1072]), whose founder member is the Drosophila Trp channel, exists in mammals as six families; TRPC, TRPM, TRPV, TRPA, TRPP and TRPML based on amino acid homologies. TRP subunits contain six putative TM domains and assemble as homo- or hetero-tetramers to form cation selective channels with diverse modes of activation and varied permeation properties (reviewed by [730]). Established, or potential, physiological functions of the individual members of the TRP families are discussed in detail in the recommended reviews and in a number of books [401, 686, 1155, 256]. The established, or potential, involvement of TRP channels in disease [1126] is reviewed in [448, 685], [688] and [464], together with a special edition of Biochemica et Biophysica Acta on the subject [685]. Additional disease related reviews, for pain [633], stroke [1135], sensation and inflammation [988], itch [130], and airway disease [310, 1051], are available. The pharmacology of most TRP channels has been advanced in recent years. Broad spectrum agents are listed in the tables along with more selective, or recently recognised, ligands that are flagged by the inclusion of a primary reference. See Rubaiy (2019) for a review of pharmacological tools for TRPC1/C4/C5 channels [805]. Most TRP channels are regulated by phosphoinostides such as PtIns(4,5)P2 although the effects reported are often complex, occasionally contradictory, and likely to be dependent upon experimental conditions, such as intracellular ATP levels (reviewed by [1009, 689, 801]). Such regulation is generally not included in the tables.When thermosensitivity is mentioned, it refers specifically to a high Q10 of gating, often in the range of 10-30, but does not necessarily imply that the channel's function is to act as a 'hot' or 'cold' sensor. In general, the search for TRP activators has led to many claims for temperature sensing, mechanosensation, and lipid sensing. All proteins are of course sensitive to energies of binding, mechanical force, and temperature, but the issue is whether the proposed input is within a physiologically relevant range resulting in a response. TRPA (ankyrin) familyTRPA1 is the sole mammalian member of this group (reviewed by [293]). TRPA1 activation of sensory neurons contribute to nociception [414, 890, 602]. Pungent chemicals such as mustard oil (AITC), allicin, and cinnamaldehyde activate TRPA1 by modification of free thiol groups of cysteine side chains, especially those located in its amino terminus [575, 60, 365, 577]. Alkenals with α, β-unsaturated bonds, such as propenal (acrolein), butenal (crotylaldehyde), and 2-pentenal can react with free thiols via Michael addition and can activate TRPA1. However, potency appears to weaken as carbon chain length increases [26, 60]. Covalent modification leads to sustained activation of TRPA1. Chemicals including carvacrol, menthol, and local anesthetics reversibly activate TRPA1 by non-covalent binding [424, 511, 1081, 1080]. TRPA1 is not mechanosensitive under physiological conditions, but can be activated by cold temperatures [425, 212]. The electron cryo-EM structure of TRPA1 [740] indicates that it is a 6-TM homotetramer. Each subunit of the channel contains two short ‘pore helices’ pointing into the ion selectivity filter, which is big enough to allow permeation of partially hydrated Ca2+ ions. TRPC (canonical) familyMembers of the TRPC subfamily (reviewed by [284, 778, 18, 4, 94, 446, 739, 70]) fall into the subgroups outlined below. TRPC2 is a pseudogene in humans. It is generally accepted that all TRPC channels are activated downstream of Gq/11-coupled receptors, or receptor tyrosine kinases (reviewed by [765, 953, 1072]). A comprehensive listing of G-protein coupled receptors that activate TRPC channels is given in [4]. Hetero-oligomeric complexes of TRPC channels and their association with proteins to form signalling complexes are detailed in [18] and [447]. TRPC channels have frequently been proposed to act as store-operated channels (SOCs) (or compenents of mulimeric complexes that form SOCs), activated by depletion of intracellular calcium stores (reviewed by [741, 18, 770, 820, 1121, 157, 726, 64, 158]). However, the weight of the evidence is that they are not directly gated by conventional store-operated mechanisms, as established for Stim-gated Orai channels. TRPC channels are not mechanically gated in physiologically relevant ranges of force. All members of the TRPC family are blocked by 2-APB and SKF96365 [347, 346]. Activation of TRPC channels by lipids is discussed by [70]. Important progress has been recently made in TRPC pharmacology [805, 619, 436, 102, 851, 191, 291]. TRPC channels regulate a variety of physiological functions and are implicated in many human diseases [295, 71, 885, 1031, 1025, 154, 103, 561, 913, 409]. TRPC1/C4/C5 subgroup TRPC1 alone may not form a functional ion channel [229]. TRPC4/C5 may be distinguished from other TRP channels by their potentiation by micromolar concentrations of La3+. TRPC2 is a pseudogene in humans, but in other mammals appears to be an ion channel localized to microvilli of the vomeronasal organ. It is required for normal sexual behavior in response to pheromones in mice. It may also function in the main olfactory epithelia in mice [1114, 723, 724, 1115, 539, 1168, 1109].TRPC3/C6/C7 subgroup All members are activated by diacylglycerol independent of protein kinase C stimulation [347].TRPM (melastatin) familyMembers of the TRPM subfamily (reviewed by [275, 346, 741, 1151]) fall into the five subgroups outlined below. TRPM1/M3 subgroupIn darkness, glutamate released by the photoreceptors and ON-bipolar cells binds to the metabotropic glutamate receptor 6 , leading to activation of Go . This results in the closure of TRPM1. When the photoreceptors are stimulated by light, glutamate release is reduced, and TRPM1 channels are more active, resulting in cell membrane depolarization. Human TRPM1 mutations are associated with congenital stationary night blindness (CSNB), whose patients lack rod function. TRPM1 is also found melanocytes. Isoforms of TRPM1 may present in melanocytes, melanoma, brain, and retina. In melanoma cells, TRPM1 is prevalent in highly dynamic intracellular vesicular structures [398, 708]. TRPM3 (reviewed by [714]) exists as multiple splice variants which differ significantly in their biophysical properties. TRPM3 is expressed in somatosensory neurons and may be important in development of heat hyperalgesia during inflammation (see review [941]). TRPM3 is frequently coexpressed with TRPA1 and TRPV1 in these neurons. TRPM3 is expressed in pancreatic beta cells as well as brain, pituitary gland, eye, kidney, and adipose tissue [713, 940]. TRPM3 may contribute to the detection of noxious heat [1017]. TRPM2TRPM2 is activated under conditions of oxidative stress (respiratory burst of phagocytic cells). The direct activators are calcium, adenosine diphosphate ribose (ADPR) [970] and cyclic ADPR (cADPR) [1118]. As for many ion channels, PI(4,5)P2 must also be present [1109]. Numerous splice variants of TRPM2 exist which differ in their activation mechanisms [239]. Recent studies have reported structures of human (hs) TRPM2, which demonstrate two ADPR binding sites in hsTRPM2, one in the N-terminal MHR1/2 domain and the other in the C-terminal NUDT9-H domain. In addition, one Ca2+ binding site in the intracellular S2-S3 loop is revealed and proposed to mediate Ca2+ binding that induces conformational changes leading the ADPR-bound closed channel to open [387, 1027]. Meanwhile, a quadruple-residue motif (979FGQI982) was identified as the ion selectivity filter and a gate to control ion permeation in hsTRPM2 [1120]. TRPM2 is involved in warmth sensation [848], and contributes to several diseases [76]. TRPM2 interacts with extra synaptic NMDA receptors (NMDAR) and enhances NMDAR activity in ischemic stroke [1164]. Activation of TRPM2 in macrophages promotes atherosclerosis [1165, 1147]. Moreover, silica nanoparticles induce lung inflammation in mice via ROS/PARP/TRPM2 signaling-mediated lysosome impairment and autophagy dysfunction [1028]. Recent studies have designed various compounds for their potential to selectively inhibit the TRPM2 channel, including ACA derivatives A23, and 2,3-dihydroquinazolin-4(1H)-one derivatives [1137, 1139]. TRPM4/5 subgroupTRPM4 and TRPM5 have the distinction within all TRP channels of being impermeable to Ca2+ [1072]. A splice variant of TRPM4 (i.e.TRPM4b) and TRPM5 are molecular candidates for endogenous calcium-activated cation (CAN) channels [327]. TRPM4 is active in the late phase of repolarization of the cardiac ventricular action potential. TRPM4 deletion or knockout enhances beta adrenergic-mediated inotropy [593]. Mutations are associated with conduction defects [404, 593, 879]. TRPM4 has been shown to be an important regulator of Ca2+ entry in to mast cells [993] and dendritic cell migration [52]. TRPM5 in taste receptor cells of the tongue appears essential for the transduction of sweet, amino acid and bitter stimuli [537] TRPM5 contributes to the slow afterdepolarization of layer 5 neurons in mouse prefrontal cortex [513]. Both TRPM4 and TRPM5 are required transduction of taste stimuli [246]. TRPM6/7 subgroupTRPM6 and 7 combine channel and enzymatic activities (‘chanzymes’) [172]. These channels have the unusual property of permeation by divalent (Ca2+, Mg2+, Zn2+) and monovalent cations, high single channel conductances, but overall extremely small inward conductance when expressed to the plasma membrane. They are inhibited by internal Mg2+ at ~0.6 mM, around the free level of Mg2+ in cells. Whether they contribute to Mg2+ homeostasis is a contentious issue. PIP2 is required for TRPM6 and TRPM7 activation [810, 1077]. When either gene is deleted in mice, the result is embryonic lethality [413, 1065]. The C-terminal kinase region of TRPM6 and TRPM7 is cleaved under unknown stimuli, and the kinase phosphorylates nuclear histones [479, 480]. TRPM7 is responsible for oxidant- induced Zn2+ release from intracellular vesicles [3] and contributes to intestinal mineral absorption essential for postnatal survival [622]. The putative metal transporter proteins CNNM1-4 interact with TRPM7 and regulate TRPM7 channel activity [40, 467]. TRPM8Is a channel activated by cooling and pharmacological agents evoking a ‘cool’ sensation and participates in the thermosensation of cold temperatures [63, 178, 224] reviewed by [1011, 562, 457, 649]. Direct chemical agonists include menthol and icilin[1086]. Besides, linalool can promote ERK phosphorylation in human dermal microvascular endothelial cells, down-regulate intracellular ATP levels, and activate TRPM8 [68]. Recent studies have found that TRPM8 has typical S4-S5 connectomes with clear selective filters and exowell rings [512], and have identified cryo-electron microscopy structures of mouse TRPM8 in closed, intermediate, and open states along the ligand- and PIP2-dependent gated pathways [1111]. Moreover, the last 36 amino acids at the carboxyl terminal of TRPM8 are key protein sequences for TRPM8's temperature-sensitive function [194]. TRPM8 deficiency reduced the expression of S100A9 and increased the expression of HNF4α in the liver of mice, which reduced inflammation and fibrosis progression in mice with liver fibrosis, and helped to alleviate the symptoms of bile duct disease [556]. Channel deficiency also shortens the time of hypersensitivity reactions in migraine mouse models by promoting the recovery of normal sensitivity [12]. A cyclic peptide DeC‐1.2 was designed to inhibit ligand activation of TRPM8 but not cold activation, which can eliminate the side effects of cold dysalgesia in oxaliplatin-treated mice without changing body temperature [9]. Analysis of clinical data shows that TRPM8-specific blockers WS12 can reduce tumor growth in colorectal cancer xenografted mice by reducing transcription and activation of Wnt signaling regulators and β-catenin and its target oncogenes, such as C-Myc and Cyclin D1 [732]. TRPML (mucolipin) familyThe TRPML family [782, 1132, 775, 1084, 190] consists of three mammalian members (TRPML1-3). TRPML channels are probably restricted to intracellular vesicles and mutations in the gene (MCOLN1) encoding TRPML1 (mucolipin-1) cause the neurodegenerative disorder mucolipidosis type IV (MLIV) in man. TRPML1 is a cation selective ion channel that is important for sorting/transport of endosomes in the late endocytotic pathway and specifically, fission from late endosome-lysosome hybrid vesicles and lysosomal exocytosis [822]. TRPML2 and TRPML3 show increased channel activity in low luminal sodium and/or increased luminal pH, and are activated by similar small molecules [319, 147, 877]. A naturally occurring gain of function mutation in TRPML3 (i.e. A419P) results in the varitint waddler (Va) mouse phenotype (reviewed by [782, 690]). TRPP (polycystin) familyThe TRPP family (reviewed by [216, 214, 300, 1061, 374]) or PKD2 family is comprised of PKD2 (PC2), PKD2L1 (PC2L1), PKD2L2 (PC2L2), which have been renamed TRPP1, TRPP2 and TRPP3, respectively [1072]. It should also be noted that the nomenclature of PC2 was TRPP2 in old literature. However, PC2 has been uniformed to be called TRPP2 [345]. PKD2 family channels are clearly distinct from the PKD1 family, whose function is unknown. PKD1 and PKD2 form a hetero-oligomeric complex with a 1:3 ratio. [905]. Although still being sorted out, TRPP family members appear to be 6TM spanning nonselective cation channels. TRPV (vanilloid) familyMembers of the TRPV family (reviewed by [995]) can broadly be divided into the non-selective cation channels, TRPV1-4 and the more calcium selective channels TRPV5 and TRPV6. TRPV1-V4 subfamilyTRPV1 is involved in the development of thermal hyperalgesia following inflammation and may contribute to the detection of noxius heat (reviewed by [762, 882, 922]). Numerous splice variants of TRPV1 have been described, some of which modulate the activity of TRPV1, or act in a dominant negative manner when co-expressed with TRPV1 [844]. The pharmacology of TRPV1 channels is discussed in detail in [329] and [1015]. TRPV2 is probably not a thermosensor in man [736], but has recently been implicated in innate immunity [547]. Functional TRPV2 expression is described in placental trophoblast cells of mouse [204]. TRPV3 and TRPV4 are both thermosensitive. There are claims that TRPV4 is also mechanosensitive, but this has not been established to be within a physiological range in a native environment [127, 530]. TRPV5/V6 subfamily TRPV5 and TRPV6 are highly expressed in placenta, bone, and kidney. Under physiological conditions, TRPV5 and TRPV6 are calcium selective channels involved in the absorption and reabsorption of calcium across intestinal and kidney tubule epithelia (reviewed by [1057, 205, 651, 270]).TRPV6 is reported to play a key role in calcium transport in the mouse placenta [1056].

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Blair, Nathaniel T., Ingrid Carvacho, Dipayan Chaudhuri, David E. Clapham, Katrien De Clerq, Markus Delling, Julia F. Doerner et al. « Transient Receptor Potential channels (TRP) in GtoPdb v.2023.1 ». IUPHAR/BPS Guide to Pharmacology CITE 2023, n^o 1 (26 avril 2023). http://dx.doi.org/10.2218/gtopdb/f78/2023.1.

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The TRP superfamily of channels (nomenclature as agreed by NC-IUPHAR [176, 1072]), whose founder member is the Drosophila Trp channel, exists in mammals as six families; TRPC, TRPM, TRPV, TRPA, TRPP and TRPML based on amino acid homologies. TRP subunits contain six putative TM domains and assemble as homo- or hetero-tetramers to form cation selective channels with diverse modes of activation and varied permeation properties (reviewed by [730]). Established, or potential, physiological functions of the individual members of the TRP families are discussed in detail in the recommended reviews and in a number of books [401, 686, 1155, 256]. The established, or potential, involvement of TRP channels in disease [1126] is reviewed in [448, 685], [688] and [464], together with a special edition of Biochemica et Biophysica Acta on the subject [685]. Additional disease related reviews, for pain [633], stroke [1135], sensation and inflammation [988], itch [130], and airway disease [310, 1051], are available. The pharmacology of most TRP channels has been advanced in recent years. Broad spectrum agents are listed in the tables along with more selective, or recently recognised, ligands that are flagged by the inclusion of a primary reference. See Rubaiy (2019) for a review of pharmacological tools for TRPC1/C4/C5 channels [805]. Most TRP channels are regulated by phosphoinostides such as PtIns(4,5)P2 although the effects reported are often complex, occasionally contradictory, and likely to be dependent upon experimental conditions, such as intracellular ATP levels (reviewed by [1009, 689, 801]). Such regulation is generally not included in the tables.When thermosensitivity is mentioned, it refers specifically to a high Q10 of gating, often in the range of 10-30, but does not necessarily imply that the channel's function is to act as a 'hot' or 'cold' sensor. In general, the search for TRP activators has led to many claims for temperature sensing, mechanosensation, and lipid sensing. All proteins are of course sensitive to energies of binding, mechanical force, and temperature, but the issue is whether the proposed input is within a physiologically relevant range resulting in a response. TRPA (ankyrin) familyTRPA1 is the sole mammalian member of this group (reviewed by [293]). TRPA1 activation of sensory neurons contribute to nociception [414, 890, 602]. Pungent chemicals such as mustard oil (AITC), allicin, and cinnamaldehyde activate TRPA1 by modification of free thiol groups of cysteine side chains, especially those located in its amino terminus [575, 60, 365, 577]. Alkenals with α, β-unsaturated bonds, such as propenal (acrolein), butenal (crotylaldehyde), and 2-pentenal can react with free thiols via Michael addition and can activate TRPA1. However, potency appears to weaken as carbon chain length increases [26, 60]. Covalent modification leads to sustained activation of TRPA1. Chemicals including carvacrol, menthol, and local anesthetics reversibly activate TRPA1 by non-covalent binding [424, 511, 1081, 1080]. TRPA1 is not mechanosensitive under physiological conditions, but can be activated by cold temperatures [425, 212]. The electron cryo-EM structure of TRPA1 [740] indicates that it is a 6-TM homotetramer. Each subunit of the channel contains two short ‘pore helices’ pointing into the ion selectivity filter, which is big enough to allow permeation of partially hydrated Ca2+ ions. TRPC (canonical) familyMembers of the TRPC subfamily (reviewed by [284, 778, 18, 4, 94, 446, 739, 70]) fall into the subgroups outlined below. TRPC2 is a pseudogene in humans. It is generally accepted that all TRPC channels are activated downstream of Gq/11-coupled receptors, or receptor tyrosine kinases (reviewed by [765, 953, 1072]). A comprehensive listing of G-protein coupled receptors that activate TRPC channels is given in [4]. Hetero-oligomeric complexes of TRPC channels and their association with proteins to form signalling complexes are detailed in [18] and [447]. TRPC channels have frequently been proposed to act as store-operated channels (SOCs) (or compenents of mulimeric complexes that form SOCs), activated by depletion of intracellular calcium stores (reviewed by [741, 18, 770, 820, 1121, 157, 726, 64, 158]). However, the weight of the evidence is that they are not directly gated by conventional store-operated mechanisms, as established for Stim-gated Orai channels. TRPC channels are not mechanically gated in physiologically relevant ranges of force. All members of the TRPC family are blocked by 2-APB and SKF96365 [347, 346]. Activation of TRPC channels by lipids is discussed by [70]. Important progress has been recently made in TRPC pharmacology [805, 619, 436, 102, 851, 191, 291]. TRPC channels regulate a variety of physiological functions and are implicated in many human diseases [295, 71, 885, 1031, 1025, 154, 103, 561, 913, 409]. TRPC1/C4/C5 subgroup TRPC1 alone may not form a functional ion channel [229]. TRPC4/C5 may be distinguished from other TRP channels by their potentiation by micromolar concentrations of La3+. TRPC2 is a pseudogene in humans, but in other mammals appears to be an ion channel localized to microvilli of the vomeronasal organ. It is required for normal sexual behavior in response to pheromones in mice. It may also function in the main olfactory epithelia in mice [1114, 723, 724, 1115, 539, 1168, 1109].TRPC3/C6/C7 subgroup All members are activated by diacylglycerol independent of protein kinase C stimulation [347].TRPM (melastatin) familyMembers of the TRPM subfamily (reviewed by [275, 346, 741, 1151]) fall into the five subgroups outlined below. TRPM1/M3 subgroupIn darkness, glutamate released by the photoreceptors and ON-bipolar cells binds to the metabotropic glutamate receptor 6 , leading to activation of Go . This results in the closure of TRPM1. When the photoreceptors are stimulated by light, glutamate release is reduced, and TRPM1 channels are more active, resulting in cell membrane depolarization. Human TRPM1 mutations are associated with congenital stationary night blindness (CSNB), whose patients lack rod function. TRPM1 is also found melanocytes. Isoforms of TRPM1 may present in melanocytes, melanoma, brain, and retina. In melanoma cells, TRPM1 is prevalent in highly dynamic intracellular vesicular structures [398, 708]. TRPM3 (reviewed by [714]) exists as multiple splice variants which differ significantly in their biophysical properties. TRPM3 is expressed in somatosensory neurons and may be important in development of heat hyperalgesia during inflammation (see review [941]). TRPM3 is frequently coexpressed with TRPA1 and TRPV1 in these neurons. TRPM3 is expressed in pancreatic beta cells as well as brain, pituitary gland, eye, kidney, and adipose tissue [713, 940]. TRPM3 may contribute to the detection of noxious heat [1017]. TRPM2TRPM2 is activated under conditions of oxidative stress (respiratory burst of phagocytic cells). The direct activators are calcium, adenosine diphosphate ribose (ADPR) [970] and cyclic ADPR (cADPR) [1118]. As for many ion channels, PI(4,5)P2 must also be present [1109]. Numerous splice variants of TRPM2 exist which differ in their activation mechanisms [239]. Recent studies have reported structures of human (hs) TRPM2, which demonstrate two ADPR binding sites in hsTRPM2, one in the N-terminal MHR1/2 domain and the other in the C-terminal NUDT9-H domain. In addition, one Ca2+ binding site in the intracellular S2-S3 loop is revealed and proposed to mediate Ca2+ binding that induces conformational changes leading the ADPR-bound closed channel to open [387, 1027]. Meanwhile, a quadruple-residue motif (979FGQI982) was identified as the ion selectivity filter and a gate to control ion permeation in hsTRPM2 [1120]. TRPM2 is involved in warmth sensation [848], and contributes to several diseases [76]. TRPM2 interacts with extra synaptic NMDA receptors (NMDAR) and enhances NMDAR activity in ischemic stroke [1164]. Activation of TRPM2 in macrophages promotes atherosclerosis [1165, 1147]. Moreover, silica nanoparticles induce lung inflammation in mice via ROS/PARP/TRPM2 signaling-mediated lysosome impairment and autophagy dysfunction [1028]. Recent studies have designed various compounds for their potential to selectively inhibit the TRPM2 channel, including ACA derivatives A23, and 2,3-dihydroquinazolin-4(1H)-one derivatives [1137, 1139]. TRPM4/5 subgroupTRPM4 and TRPM5 have the distinction within all TRP channels of being impermeable to Ca2+ [1072]. A splice variant of TRPM4 (i.e.TRPM4b) and TRPM5 are molecular candidates for endogenous calcium-activated cation (CAN) channels [327]. TRPM4 is active in the late phase of repolarization of the cardiac ventricular action potential. TRPM4 deletion or knockout enhances beta adrenergic-mediated inotropy [593]. Mutations are associated with conduction defects [404, 593, 879]. TRPM4 has been shown to be an important regulator of Ca2+ entry in to mast cells [993] and dendritic cell migration [52]. TRPM5 in taste receptor cells of the tongue appears essential for the transduction of sweet, amino acid and bitter stimuli [537] TRPM5 contributes to the slow afterdepolarization of layer 5 neurons in mouse prefrontal cortex [513]. Both TRPM4 and TRPM5 are required transduction of taste stimuli [246]. TRPM6/7 subgroupTRPM6 and 7 combine channel and enzymatic activities (‘chanzymes’) [172]. These channels have the unusual property of permeation by divalent (Ca2+, Mg2+, Zn2+) and monovalent cations, high single channel conductances, but overall extremely small inward conductance when expressed to the plasma membrane. They are inhibited by internal Mg2+ at ~0.6 mM, around the free level of Mg2+ in cells. Whether they contribute to Mg2+ homeostasis is a contentious issue. PIP2 is required for TRPM6 and TRPM7 activation [810, 1077]. When either gene is deleted in mice, the result is embryonic lethality [413, 1065]. The C-terminal kinase region of TRPM6 and TRPM7 is cleaved under unknown stimuli, and the kinase phosphorylates nuclear histones [479, 480]. TRPM7 is responsible for oxidant- induced Zn2+ release from intracellular vesicles [3] and contributes to intestinal mineral absorption essential for postnatal survival [622]. The putative metal transporter proteins CNNM1-4 interact with TRPM7 and regulate TRPM7 channel activity [40, 467]. TRPM8Is a channel activated by cooling and pharmacological agents evoking a ‘cool’ sensation and participates in the thermosensation of cold temperatures [63, 178, 224] reviewed by [1011, 562, 457, 649]. Direct chemical agonists include menthol and icilin[1086]. Besides, linalool can promote ERK phosphorylation in human dermal microvascular endothelial cells, down-regulate intracellular ATP levels, and activate TRPM8 [68]. Recent studies have found that TRPM8 has typical S4-S5 connectomes with clear selective filters and exowell rings [512], and have identified cryo-electron microscopy structures of mouse TRPM8 in closed, intermediate, and open states along the ligand- and PIP2-dependent gated pathways [1111]. Moreover, the last 36 amino acids at the carboxyl terminal of TRPM8 are key protein sequences for TRPM8's temperature-sensitive function [194]. TRPM8 deficiency reduced the expression of S100A9 and increased the expression of HNF4α in the liver of mice, which reduced inflammation and fibrosis progression in mice with liver fibrosis, and helped to alleviate the symptoms of bile duct disease [556]. Channel deficiency also shortens the time of hypersensitivity reactions in migraine mouse models by promoting the recovery of normal sensitivity [12]. A cyclic peptide DeC‐1.2 was designed to inhibit ligand activation of TRPM8 but not cold activation, which can eliminate the side effects of cold dysalgesia in oxaliplatin-treated mice without changing body temperature [9]. Analysis of clinical data shows that TRPM8-specific blockers WS12 can reduce tumor growth in colorectal cancer xenografted mice by reducing transcription and activation of Wnt signaling regulators and β-catenin and its target oncogenes, such as C-Myc and Cyclin D1 [732]. TRPML (mucolipin) familyThe TRPML family [782, 1132, 775, 1084, 190] consists of three mammalian members (TRPML1-3). TRPML channels are probably restricted to intracellular vesicles and mutations in the gene (MCOLN1) encoding TRPML1 (mucolipin-1) cause the neurodegenerative disorder mucolipidosis type IV (MLIV) in man. TRPML1 is a cation selective ion channel that is important for sorting/transport of endosomes in the late endocytotic pathway and specifically, fission from late endosome-lysosome hybrid vesicles and lysosomal exocytosis [822]. TRPML2 and TRPML3 show increased channel activity in low luminal sodium and/or increased luminal pH, and are activated by similar small molecules [319, 147, 877]. A naturally occurring gain of function mutation in TRPML3 (i.e. A419P) results in the varitint waddler (Va) mouse phenotype (reviewed by [782, 690]). TRPP (polycystin) familyThe TRPP family (reviewed by [216, 214, 300, 1061, 374]) or PKD2 family is comprised of PKD2 (PC2), PKD2L1 (PC2L1), PKD2L2 (PC2L2), which have been renamed TRPP1, TRPP2 and TRPP3, respectively [1072]. It should also be noted that the nomenclature of PC2 was TRPP2 in old literature. However, PC2 has been uniformed to be called TRPP2 [345]. PKD2 family channels are clearly distinct from the PKD1 family, whose function is unknown. PKD1 and PKD2 form a hetero-oligomeric complex with a 1:3 ratio. [905]. Although still being sorted out, TRPP family members appear to be 6TM spanning nonselective cation channels. TRPV (vanilloid) familyMembers of the TRPV family (reviewed by [995]) can broadly be divided into the non-selective cation channels, TRPV1-4 and the more calcium selective channels TRPV5 and TRPV6. TRPV1-V4 subfamilyTRPV1 is involved in the development of thermal hyperalgesia following inflammation and may contribute to the detection of noxius heat (reviewed by [762, 882, 922]). Numerous splice variants of TRPV1 have been described, some of which modulate the activity of TRPV1, or act in a dominant negative manner when co-expressed with TRPV1 [844]. The pharmacology of TRPV1 channels is discussed in detail in [329] and [1015]. TRPV2 is probably not a thermosensor in man [736], but has recently been implicated in innate immunity [547]. Functional TRPV2 expression is described in placental trophoblast cells of mouse [204]. TRPV3 and TRPV4 are both thermosensitive. There are claims that TRPV4 is also mechanosensitive, but this has not been established to be within a physiological range in a native environment [127, 530]. TRPV5/V6 subfamily TRPV5 and TRPV6 are highly expressed in placenta, bone, and kidney. Under physiological conditions, TRPV5 and TRPV6 are calcium selective channels involved in the absorption and reabsorption of calcium across intestinal and kidney tubule epithelia (reviewed by [1057, 205, 651, 270]).TRPV6 is reported to play a key role in calcium transport in the mouse placenta [1056].

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