Journal articles on the topic 'Cobra probe'
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De Guzman, M. M., C. A. J. Fletcher, and J. D. Hooper. "Computational Investigation of Cobra probe operation." International Journal of Numerical Methods for Heat & Fluid Flow 4, no. 5 (May 1994): 425–45. http://dx.doi.org/10.1108/eum0000000004047.
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De Guzman, M. M., C. A. J. Fletcher, and M. Behnia. "Gas particle flows about a Cobra probe with purging." Computers & Fluids 24, no. 2 (February 1995): 121–34. http://dx.doi.org/10.1016/0045-7930(94)00026-u.
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Miller, E. C., M. R. L’Ecuyer, and E. F. Benisek. "Flow Field Surveys at the Rotor Inlet of a Radial Inflow Turbine." Journal of Engineering for Gas Turbines and Power 110, no. 3 (July 1, 1988): 552–61. http://dx.doi.org/10.1115/1.3240170.
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Experiments were performed using a five-port cobra probe to survey the flow field at the rotor inlet of a 110-mm-dia turbocharger radial inflow turbine wheel. The turbine housing was modified to accommodate a probe insert to position the probe tip 4.1 mm above the rotor tip while preserving the internal contour of the production turbine housing. The cobra probe was traversed axially and circumferentially to determine the rotor inlet flow properties while the turbine was operated at design flow conditions with a reduced turbine inlet temperature. Measurements were made with the probe tip in the near-nulled position to determine the local values of total pressure, static pressure, velocity, and flow angle as functions of Z and θ. Results are presented showing the distribution of the housing total pressure loss coefficient, the rotor inlet mass flux, and the rotor inlet tangential velocity. In addition, values for rotor inlet mass average properties are given.
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Coldrick, Simon, Paul Ivey, and Roger Wells. "Considerations for Using 3-D Pneumatic Probes in High-Speed Axial Compressors." Journal of Turbomachinery 125, no. 1 (January 1, 2003): 149–54. http://dx.doi.org/10.1115/1.1515334.
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This paper describes preparatory work towards three-dimensional flowfield measurements downstream of the rotor in an industrial, multistage, axial compressor, using a pneumatic pressure probe. The probe is of the steady-state four-hole cobra probe type. The design manufacture and calibration of the probe is described. CFD calculations have been undertaken in order to assess the feasibility of using such a probe in the high-speed compressor environment where space is limited. This includes effects of mounting the probe in close proximity to the downstream stator blades and whether it is necessary to adjust the calibration data to compensate for these effects.
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Harada, H. "Performance Characteristics of Shrouded and Unshrouded Impellers of a Centrifugal Compressor." Journal of Engineering for Gas Turbines and Power 107, no. 2 (April 1, 1985): 528–33. http://dx.doi.org/10.1115/1.3239765.
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The overall performance of shrouded and unshrouded identical impellers of a centrifugal compressor were tested and compared. A closed loop test stand with Freon gas as the working fluid was employed for the experiments. The inlet and outlet velocity distributions of both impellers were measured using a three-hole cobra probe and a hot-film probe to determine the velocity distribution and unsteady flows due to wakes and inlet stall.
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An, Jian-xiong. "Trigeminal Neuralgia Induced by Cobra Venom in the Rat Leads to Deficits in Abilities of Spatial Learning and Memory." Pain Physician 2;18, no. 2;3 (March 14, 2015): E207—E216. http://dx.doi.org/10.36076/ppj/2015.18.e207.
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Background: Patients with chronic pain usually suffer from cognitive impairment, with memory deterioration being the most common deficit that affects daily functioning and quality of life. The causes for this impairment are not clear despite intensive clinical studies. Few studies have evaluated impaired learning using animal models of persistent pain. Objective: In this study, a new trigeminal neuralgia model induced by cobra venom was adopted to explore effects of chronic pain on spatial learning and memory in rats. Study Design: Controlled animal study. Setting: Department of Anesthesiology, Pain Medicine & Critical Care Medicine, Aviation General Hospital of China Medical University. Methods: Thirty adult male Sprague-Dawley rats were randomly divided into 2 groups (n = 15): NS control group and cobra venom group, 0.9% sterile saline or cobra venom solution was injected into the sheath of the infraorbital nerve (ION), respectively. The development of trigeminal neuralgia was accessed by changes in free behavioral activity 3 days before the surgery and 3, 7, 12, 20, and 30 days after the surgery to identify whether the model was successful or not. Morris water maze test determined the abilities of spatial learning and memory at the time points before the surgery, and 2 weeks and 5 weeks after the surgery. We also observed the ultrastructure of the ION and medulla oblongata of rats following 8 weeks of chronic trigeminal neuropathic pain. Results: Rats with the cobra venom injection displayed significantly more face grooming and fewer exploratory activities compared to the NS control group or baseline (P < 0.01). Both groups improved their latency to reach the platform with the largest difference on the first day (P < 0.01), but without memory deficits in a probe trial for the second water maze protocol. For the third water maze testing, the rats in the cobra venom group experienced decreased abilities of spatial learning and memory, a longer latency with spatial memory deficits during the probe trial (P < 0.05). At the ultrastructural level, we found changes in the medulla oblongata after cobra venom injection resulting in severe demyelination and loss of axons that might be implicated in the causes of cognitive deficits. Limitations: Limitations include partial vision loss in the eye on the lesion side of the rats that might be missed and the absence of evaluating the ultrastructural changes in other parts of the brain. Conclusions: The results of this study suggest that trigeminal neuralgia induced by cobra venom in adult rats can impair spatial learning and memory function over time and results in demonstrable changes in the ultrastructure of the medulla oblongata. This new animal model may be useful for future studies on the effect of chronic pain on learning and cognition. Key words: Cognitive deficits, memory deterioration, cobra venom, trigeminal neuralgia, electron microscopy
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An, Jianxiong. "Trigeminal Neuralgia Induced by Cobra Venom Leads to Cognitive Deficits Associated with Downregulation of CREB/BDNF Pathway." Pain Physician 2, no. 20;2 (February 14, 2017): 53–67. http://dx.doi.org/10.36076/ppj/2017/67.
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Background: Chronic pain often results in cognitive impairment. Our previous study showed that trigeminal neuralgia induced by cobra venom leads to spatial learning and memory deficits, although the underlying mechanism remains unclear. However, recent evidence indicates that the c-AMP-responsive element binding protein (CREB)/brain derived neurotrophic factor (BDNF) pathway plays a critical role in various etiologies of cognitive deficits. Objectives: Our aim was to explore the CREB/BDNF pathway to determine the molecular mechanisms involved in the pathogenesis of cognitive impairment caused by cobra venominduced trigeminal neuralgia. Study Design: A randomized, controlled animal study. Setting: Department of Anesthesiology, Beijing Friendship Hospital, Capital Medical University. Methods: Fifty male Sprague–Dawley rats were randomly divided into 3 groups: cobra venom group, sham group, and control group. Cobra venom or saline was injected into the sheath of the infraorbital nerve (ION), respectively. Video recordings and mechanical thresholds were used to analyze changes in behavioral activity 3 days before surgery and 4, 7, 14, 21, 28, and 56 days after surgery. Morris water maze tests were conducted at 4- and 8-week time points after surgery to evaluate spatial learning and memory. We also investigated expression changes of phosphorylated CREB (p-CREB) and BDNF in the hippocampus and prefrontal cortex (PFC) using western blotting and immunohistochemistry. Results: Cobra venom-treated rats exhibited significant changes in face grooming, as well as exploratory and resting behaviors, compared with the control group and sham group (both P < 0.001). Rats in the cobra venom group exhibited slightly impaired acquisition (P < 0.05) without memory deficits (P > 0.05) in the first water maze protocol. In the second water maze test, rats in the cobra venom group exhibited spatial learning and memory deficits, with fewer platform site crossings during the probe trial (P < 0.05). Moreover, results showed decreased p-CREB and BDNF expressions in the hippocampus and PFC in the cobra venom group, with significant differences at 9 weeks post-surgery (P < 0.05). Limitations: No signaling inhibitor or genetic manipulation was administered to further confirm upstream factors of the CREB/BDNF pathway in cognitive deficits caused by chronic trigeminal neuralgia. Conclusions: The findings suggest that cognitive impairment caused by cobra venom-induced trigeminal neuralgia is associated with downregulation of the CREB/BDNF pathway in the hippocampus and PFC. Key words: Cognitive impairment, the CREB/BDNF pathway, cobra venom, trigeminal neuralgia, hippocampus, prefrontal cortex, free behavior, Morris water maze
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Chen, J., B. S. Haynes, and D. F. Fletcher. "Cobra probe measurements of mean velocities, Reynolds stresses and higher-order velocity correlations in pipe flow." Experimental Thermal and Fluid Science 21, no. 4 (May 2000): 206–17. http://dx.doi.org/10.1016/s0894-1777(00)00004-2.
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Aripov, T. F., U. M. Beknazarov, and V. G. Omel'yanenko. "An investigation of the interaction of cobra venom cytotoxins with liposomes by the fluorescent-probe method." Chemistry of Natural Compounds 22, no. 6 (November 1986): 703–6. http://dx.doi.org/10.1007/bf00598357.
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Li, Chun Guang, Yang Liu, and John C. K. Cheung. "Wind Tunnel Test of Honeycomb in Improving Flow Quality." Advanced Materials Research 774-776 (September 2013): 275–78. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.275.
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The function of honeycomb with different length and width in improving flow quality were studied in the course of building a new small section open loop wind tunnel. Instantaneous velocities of turbulent flow in the tunnel were measured by cobra probe. The focus of this study was put on the effect of the honeycomb in attenuating the total turbulence intensity including the free-turbulence carried by the incoming flow and the turbulence generated by the square cells themselves. The change tendency of the mean wind velocity and the total turbulence characteristics in the decay area have been studied by varying the length to cell size ratio L/D, and ratio of distance between the square cells and the measuring position to cell size X/D.
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Sitaram, N., and J. M. Issac. "An experimental investigation of a centrifugal compressor with hub vane diffusers." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 211, no. 5 (August 1, 1997): 411–27. http://dx.doi.org/10.1243/0957650971537312.
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The present investigation reports results of experimental studies on a centrifugal compressor equipped with hub vane diffusers. The diffuser vane height ( h/b) is varied as follows: 0 (vaneless), 0.2, 0.3, 0.4 and 1 (vane). The experiments were carried out on a low specific speed centrifugal compressor with a radial tipped impeller with an inducer at the inlet. The measurements consist of determining performance characteristics, measuring static pressures on the hub and shroud and flow traverses with a precalibrated cobra probe at the diffuser exit over one passage at five flow coefficients, viz. φ = 0.23 (near surge), 0.34 (near peak pressure rise), 0.45, 0.60 and 0.75 (near maximum flow). The peak energy coefficient is maximum for the hub vane diffuser with an h/b ratio of 0.2. The hub vane diffusers have a wider operating range than the vane diffuser. At high flow coefficients, the static pressure rise is substantially low at the throat region of the vane diffuser as the incidence on to the vane leading edge is very high. The mass averaged static pressure coefficient is high in the low-volume range for the hub vane diffuser of h/b = 0.3, but in the high-volume range it is high for the vaneless diffuser.
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Zaidi, Sohail H., and Robin L. Elder. "Flow Studies using Laser Anemometry Technique in a Small Power Unit Radial Inflow Turbine." International Journal of Rotating Machinery 3, no. 2 (1997): 107–15. http://dx.doi.org/10.1155/s1023621x97000110.
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T-100 is a multipurpose small power unit developed by Sundstrand Power Systems (USA). An extensive research programme was launched for the detailed tests of the rig components including inlet protection system, Compressor stage, Combustor and the Turbine stage. Turbomachinery Group at Cranfield was involved in the study of the Turbine unit used in this programme. From the design point of view, detailed aerodynamics in these small units are of great interest especially where high velocities and narrow passages are involved. Experimental study was carried out to investigate the flow in the region between the nozzle guide vanes and the turbine rotor entry. The main concern was to find out how the nozzle guide vane flow was modified by the rotor and how the rotor flow was affected by the nozzle guide vanes. Laser measurements were taken at these positions for various flow conditions. An other area which needs considerable attention is downstream of the turbine rotor where the turning of flow and mixing process make the situation very complicated. Laser studies were undertaken in that region and to gain more confidence on laser results, a Cobra pressure probe was traversed at these stations. This paper describes various steps undertaken to obtain laser results within the machine. At the end typical laser results have been presented and discussed.
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NAKAGAWA, Katsuhiro, Yasushi KITAMURA, Hiroshi HANADO, Nobuhiro TAKAHASHI, and Toshio IGUCHI. "VERTICAL CHARACTERISCTCS OF RAINFALL USING C-BAND MULTI PARAMETER DOPPLER RADAR (COBRA)." PROCEEDINGS OF HYDRAULIC ENGINEERING 49 (2005): 277–82. http://dx.doi.org/10.2208/prohe.49.277.
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Spertini, O., A. S. Cordey, N. Monai, L. Giuffrè, and M. Schapira. "P-selectin glycoprotein ligand 1 is a ligand for L-selectin on neutrophils, monocytes, and CD34+ hematopoietic progenitor cells." Journal of Cell Biology 135, no. 2 (October 15, 1996): 523–31. http://dx.doi.org/10.1083/jcb.135.2.523.
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Selectins play a critical role in initiating leukocyte binding to vascular endothelium. In addition, in vitro experiments have shown that neutrophils use L-selectin to roll on adherent neutrophils, suggesting that they express a nonvascular L-selectin ligand. Using a L-selectin/IgM heavy chain (mu) chimeric protein as an immunocytological probe, we show here that L-selectin can bind to neutrophils, monocytes, CD34+ hematopoietic progenitors, and HL-60 and KG-1 myeloid cells. The interaction between L-selectin and leukocytes was protease sensitive and calcium dependent, and abolished by cell treatment with neuraminidase, chlorate, or O-sialoglycoprotein endopeptidase. These results revealed common features between leukocyte L-selectin ligand and the mucin-like P-selectin glycoprotein ligand 1 (PSGL-1), which mediates neutrophil rolling on P- and E-selectin. The possibility that PSGL-1 could be a ligand for L-selectin was further supported by the ability of P-selectin/mu chimera to inhibit L-selectin/mu binding to leukocytes and by the complete inhibition of both selectin interactions with myeloid cells treated with mocarhagin, a cobra venom metalloproteinase that cleaves the amino terminus of PSGL-1 at Tyr-51. Finally, the abrogation of L- and P-selectin binding to myeloid cells treated with a polyclonal antibody, raised against a peptide corresponding to the amino acid residues 42-56 of PSGL-1, indicated that L- and P-selectin interact with a domain located at the amino-terminal end of PSGL-1. The ability of the anti-PSGL-1 mAb PL-1 to inhibit L- and P-selectin binding to KG-1 cells further supported that possibility. Thus, apart from being involved in neutrophil rolling on P- and E-selectin, PSGL-1 also plays a critical role in mediating neutrophil attachment to adherent neutrophils. Interaction between L-selectin and PSGL-1 may be of major importance for increasing leukocyte recruitment at inflammatory sites.
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Budiman, Diana, Dadang Dadang, and Idham Sakti Harahap. "Keefektifan tiga jenis perangkap serangga untuk deteksi serangga hama gudang yang menyerang bungkil kopra." Jurnal Entomologi Indonesia 17, no. 1 (April 29, 2020): 1. http://dx.doi.org/10.5994/jei.17.1.1.
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<p>Stored product insect can cause consumer rejection and economic loss due to quality concerns and phytosanitary regulation. Insect traps have been regularly used as a control method, however its effectiveness on controlling stored copra meal insect pests is not yet known.This study was carried out to compare the effectiveness of three types of insect traps for detection of insect pests of copra meal.The three types of insect traps were pitfall trap, probe trap, and ultraviolet (UV) light trap (blacklight and LED-light emiting diodes). Research was conducted at Laboratory of Entomology SEAMEO BIOTROP, Bogor and two storage facilities of copra meal in North Sulawesi. Laboratory experiment was conducted using completely randomized design with two factors and four replications. The first factor was the types of insect traps (pitfall trap, probe trap, and probe trap with UV LED) and the second factor was insect species (<em>Lasioderma serricorne</em> (Herbst) and <em>Tribolium castaneum </em>(Fabricius)). The experiment at storage facilities was conducted with nested block design where the insect species trapped were nested in the insect traps. The result of laboratory experiment showed that the probe trap captured more insects (30.4%) significantly higher than pitfall trap (17.1%), however there was no significant difference of number of insects trapped in probe trap with and without UV LED. In addition the probe trap captured more <em>T. castaneum</em> and <em>Tenebroides mauritanicus</em> than other type of insects trap, but probe trap with UV LED was more effective to detect <em>L. serricorne</em> and <em>Necrobia rufipes</em> (Fabricius) in the stored copra meal.</p>
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Núñez Marín, Raúl Fernando. "Estándares internacionales en materia de orientación sexual e identidad de género: interpretación evolutiva en el derecho interamericano." Prolegómenos 22, no. 43 (February 24, 2020): 9–20. http://dx.doi.org/10.18359/prole.3094.
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La discusión jurídica frente a los derechos de las minorías se encuentra en pleno auge. Tanto los sistemas domésticos como los sistemas de derecho internacional se enfrentan a los retos de un mundo cada vez más diverso, en el que la distinción entre mayorías y minorías tiende a ser innecesaria. Es así como la temática de los derechos de las comunidades LGBTI cobra vigencia. El derecho internacional ha fijado estándares que permiten dar una interpretación amplia y evolutiva a sus derechos, basándose en nuevos conceptos sobre la orientación sexual y la identidad de género, en lo referente a la igualdad, y, como consecuencia de sus derechos al matrimonio y a la familia. Su análisis requiere del uso de fuentes formales y de soft law, así como del derecho comparado.
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KITAMURA, Yasushi, Katsuhiro NAKAGAWA, Shinya SEKIZAWA, Hiroshi HANADO, Nobuhiro TAKAHASHI, and Toshio IGUCHI. "DEVELOPMENT OF A METHOD TO ESTIMATE OF DROP SIZE DISTRIBUTION ABOVE THE MELTING LAYER BY USING 400MHz-BAND WIND PROFILER AND COBRA." PROCEEDINGS OF HYDRAULIC ENGINEERING 51 (2007): 349–54. http://dx.doi.org/10.2208/prohe.51.349.
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Tsakstara, V., T. S. Kosmas, and J. Sinatkas. "Nuclear response to supernova neutrino spectra." HNPS Proceedings 18 (November 23, 2019): 187. http://dx.doi.org/10.12681/hnps.2551.
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In current probes searching for rare event processes, appropriate nuclear targets are employed (in the COBRA double-beta decay detector the CdZnTe semiconductor is used). In this work the response of such detectors to various low-energy neutrino spectra is explored starting from state-by-state calculations of the neutrino-nucleus reactions cross sections obtained by using the quasi particle random phase approximation (QRPA) based on realistic two-body residual interactions. As a concrete example, we examine the response of 64Zn isotope to low energy supernova neutrinos.
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Harada, H. "Performance Characteristics of Two- and Three-Dimensional Impellers in Centrifugal Compressors." Journal of Turbomachinery 110, no. 1 (January 1, 1988): 110–14. http://dx.doi.org/10.1115/1.3262155.
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The overall performance of two- and three-dimensional impellers of a centrifugal compressor were tested and compared. A closed-loop test stand with Freon gas as the working fluid was employed for the experiments. The inlet and outlet velocity distributions of all impellers were measured using three-hole cobra probes. As a result, it has been revealed that three-dimensional impeller in terms of efficiency, head coefficient, and operating range. Further, it has also been clarified that the impeller slip factor is affected by blade angle distribution.
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Wang, Michael X., Deiter Duff, Huidong Shi, Kristen H. Taylor, Barbara A. Gruner, and Charles W. Caldwell. "Detection of Minimal Residual Disease in Precursor B Lymphoblastic Leukemia (B-ALL) Patients by a Novel Epigenetic DNA Methylation Biomarker." Blood 106, no. 11 (November 16, 2005): 4524. http://dx.doi.org/10.1182/blood.v106.11.4524.4524.
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Abstract Background: Increasing evidence indicates that the minimal residual disease in childhood precursor B lymphoblastic leukemia (B-ALL) can predict the clinical outcome of the patients. With the combination of multicolor flow cytometry and B-cell receptor gene rearrangement or gene translocation analysis, the majority of minimal residual disease can be detected at the 10−5 level. However, these methods may suffer from high cost and complexity and result in false negatives due to antigen shift or lack of genetic markers. Aberrant DNA hypermethylation in CpG islands of tumor suppressor genes is a hallmark of many human malignancies including B-ALL. Since the DNA methyltransferase 1 (DNMT1) is a component of replisome at the DNA replication fork, the methylation in cytosine is precisely duplicated in each cell cycle. Thus the DNA methylation status is maintained and can be detected in the minimal residual leukemic cells if the original clone has DNA methylation markers. Methods: We developed a new method for detection of minimal residual disease in B-ALL patients using a specific DNA methylation marker in the promoter region of the tumor suppressor gene DLC-1 (deleted in liver cancer -1). The quantitative real-time methylation specific PCR (qMSP) was utilized as a primary detection method and it was validated via combined bisulfite restriction analysis (COBRA). The qMSP uses two specifically designed amplification primers which are complementary only for bisulfite-treated methylated DNA sequences and an additional fluorogenic probe specificlly hybridizing methylated target amplicons. Results: By using highly sensitive qMSP assay, we demonstrated that DNA methylation of the DLC-1 gene promoter occurred in 15 out of 20 (75 %) of B-ALL patient bone marrow aspirate specimens and 2 (NALM-6 and MN60) out of 3 B-ALL cell lines. DLC-1 methylation was detected in multiple sequential specimens (up to 6 time points) from 3 childhood B-ALL patients and is comparable with morphologic, flow cytometry and B-cell receptor gene rearrangement (in 5 specimens) assessment. In addition, DLC-1 methylation in different types of specimens collected at the same time point including frozen bone marrow aspirate, unstained bone marrow aspirate slides, fresh peripheral blood, and unstained peripheral blood smear showed complete consistency. Finally, the analytic sensitivity of qMSP was determined by a series of dilution of tumor cell DNA (MN60) in normal human genomic DNA. Ten ng of tumor DNA can be detected in 1 μg of normal DNA. The co-efficient of variation (CV) of the intra- and inter- measurements was about 0.5% and 1.5% by Ct values, respectively. Conclusion: We have developed a novel real-time methylation specific PCR method to detect minimal residual disease in B-ALL patients. The method is sensitive, quantitative, simple and fast, and has the potential to be used for routine clinical minimal residual disease detection in majority of B-ALL patients. The analytic sensitivity and specificity of this method are compatible with flow cytometric and molecular analysis. A study with larger number of B-ALL patient specimens using this novel method is currently underway.
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Szuhai, Karoly, and Hans J. Tanke. "COBRA: combined binary ratio labeling of nucleic-acid probes for multi-color fluorescence in situ hybridization karyotyping." Nature Protocols 1, no. 1 (June 2006): 264–75. http://dx.doi.org/10.1038/nprot.2006.41.
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Gorai, Biswajit, and Thirunavukkarasu Sivaraman. "Unfolding stabilities of two paralogous proteins from Naja naja naja (Indian cobra) as probed by molecular dynamics simulations." Toxicon 72 (September 2013): 11–22. http://dx.doi.org/10.1016/j.toxicon.2013.05.024.
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Blanton, Elizabeth L., Rachel Paterno-Mahler, Joshua D. Wing, M. L. N. Ashby, Emmet Golden-Marx, Mark Brodwin, E. M. Douglass, Scott W. Randall, and T. E. Clarke. "Extragalactic jets as probes of distant clusters of galaxies and the clusters occupied by bent radio AGN (COBRA) survey." Proceedings of the International Astronomical Union 10, S313 (September 2014): 315–20. http://dx.doi.org/10.1017/s1743921315002410.
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AbstractWe are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas found in clusters of galaxies. Based on low-redshift studies, these types of sources can be used to identify clusters very efficiently. We present initial results from our survey of 653 bent-double radio sources with optical hosts too faint to appear in the SDSS. The sample was observed in the infrared with Spitzer, and it has revealed ~200 distant clusters or proto-clusters in the redshift range z ~ 0.7 - 3.0. The sample of bent-doubles contains both quasars and radio galaxies enabling us to study both radiative and kinetic mode feedback in cluster and group environments at a wide range of redshifts.
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Mosquera Barraza, Angelita Linda. "Reglamentación acto cooperativo - uso indebido de prerrogativas otorgadas por la ley a entidades de economía solidaria." Prolegómenos 15, no. 29 (February 1, 2012): 129–48. http://dx.doi.org/10.18359/prole.2373.
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<p>Las cooperativas son personas jurídicas que pueden realizar contratos, comparecer en juicio y actuar en todo aquello que esté conforme con su índole social y económica. Sus actos son de comercio en la forma, pero no en la esencia, por no existir el lucro, por no reunir todas sus características formales.</p><p>Se distinguen entre actos internos y externos. Los primeros son los celebrados entre los asociados y la cooperativa; los segundos, los celebrados con terceros no asociados, pero para beneficio de sus asociados, o mejor dicho, para poder cumplir el fin social. Lo que se pretende en reconocer el espíritu del cooperativismo, lo que conduce al punto central de este trabajo: "El acto cooperativo" desde la perspectiva de su reglamentación.</p><p>Las organizaciones de la economía solidaria, han sido creadas, como su nombre lo indica, con el espíritu de protección hacia los más necesitados, ofreciendo servicios de mayor acceso a las poblaciones más vulnerables; pero esto se ha desvirtuado por estas entidades al aprobar créditos desconociendo algunos de los derechos y a su vez excediendo los límites de sus actuaciones, al usar las prerrogativas otorgadas por la ley y realizar embargo de pensiones y salarios de personas que no son asociados o que no ejercen sus derechos como tal, lo que constatamos con el mayor número de quejas que presentan los usuarios en la Superintendencia de la Economía Solidaria por el tema de Usura y otras irregularidades en el otorgamiento y cobro de créditos.</p><p>Se sugiere entonces la reglamentación del acto cooperativo dentro de nuestra legislación colombiana a través de una Ley, Decreto o norma imperativa que le de fuerza o herramientas a los colombianos y a las entidades de control para actuar en contra de los administradores o entidades solidarias que cometen este tipo de actuaciones contrarias a derecho.</p><p>Es claro ver la profunda importancia del tema propuesto, dado que el cooperativismo y la economía solidaria son objeto de una regulación legal cada vez más amplia en nuestro país por la importancia y la forma como afecta las decisiones a nivel nacional en lo laboral y otro muchos aspectos que inicialmente se desarrollaron sin ningún marco normativo, como es el caso de varias de las formas asociativas que fueron ideadas para solucionar problemas económicos, sociales, culturales y ambientales, terminaron por ser reglamentados jurídicamente (Sarmiento & Guarín, 1999).</p>
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Jacobina, Uedson Pereira, Marcelo de Bello Cioffi, Luiz Gustavo Rodrigues Souza, Leonardo Luiz Calado, Manoel Tavares, João Manzella, Luiz Antonio Carlos Bertollo, and Wagner Franco Molina. "Chromosome Mapping of Repetitive Sequences inRachycentron canadum(Perciformes: Rachycentridae): Implications for Karyotypic Evolution and Perspectives for Biotechnological Uses." Journal of Biomedicine and Biotechnology 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/218231.
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The cobia,Rachycentron canadum, a species of marine fish, has been increasingly used in aquaculture worldwide. It is the only member of the family Rachycentridae (Perciformes) showing wide geographic distribution and phylogenetic patterns still not fully understood. In this study, the species was cytogenetically analyzed by different methodologies, including Ag-NOR and chromomycin A3(CMA3)/DAPI staining, C-banding, early replication banding (RGB), andin situfluorescent hybridization with probes for 18S and 5S ribosomal genes and for telomeric sequences (TTAGGG)n. The results obtained allow a detailed chromosomal characterization of the Atlantic population. The chromosome diversification found in the karyotype of the cobia is apparently related to pericentric inversions, the main mechanism associated to the karyotypic evolution of Perciformes. The differential heterochromatin replication patterns found were in part associated to functional genes. Despite maintaining conservative chromosomal characteristics in relation to the basal pattern established for Perciformes, some chromosome pairs in the analyzed population exhibit markers that may be important for cytotaxonomic, population, and biodiversity studies as well as for monitoring the species in question.
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Brown, Christopher, Timothy Crouch, David Burton, and Mark C. Thompson. "Understanding the Aerodynamic Benefits of Drafting in the Wake of Cyclists." Proceedings 49, no. 1 (June 15, 2020): 32. http://dx.doi.org/10.3390/proceedings2020049032.
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A new approach is presented to characterize the aerodynamic benefit from riding in the wake of another cyclist at different downstream locations. The method presented uses the dynamic pressure deficit in the wake of a cycling mannequin to estimate percentage drag savings. In the experiments, the time-averaged velocity behind a cycling mannequin was recorded in 1 × 0.95 m cross-planes by two four-hole pressure (Cobra) probes for four static leg positions (0°, 90°, 180°, and 270°). It was found that the wake of the cycling mannequin propagated to one side or the other as it developed downstream, depending on the strength of the two large-scale counter-rotating streamwise vortical structures shed off the hips of the mannequin. In the near wake, the complex wake dynamics resulted in an inaccurate prediction of the relative drag reduction based upon a dynamic pressure deficit. However, as the wake developed and stabilised further downstream, the dynamic pressure deficit was found to provide a reasonable estimate of the aerodynamic drag reduction of riding in the wake of the lead rider.
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del Real, I., J. F. H. Thompson, A. C. Simon, and M. Reich. "Geochemical and Isotopic Signature of Pyrite as a Proxy for Fluid Source and Evolution in the Candelaria-Punta del Cobre Iron Oxide Copper-Gold District, Chile." Economic Geology 115, no. 7 (November 1, 2020): 1493–518. http://dx.doi.org/10.5382/econgeo.4765.
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Abstract Pyrite is ubiquitous in the world-class iron oxide copper-gold (IOCG) deposits of the Candelaria-Punta del Cobre district, documented from early to late stages of mineralization and observed in deep and shallow levels of mineralized bodies. Despite its abundance, the chemical and isotopic signature of pyrite from the Candelaria-Punta del Cobre district, and most IOCG deposits worldwide, remains poorly understood. We evaluated in situ chemical and isotopic variations at the grain scale in a set of pyrite-bearing samples collected throughout the district in order to characterize and further understand the nature of mineralization in this IOCG system. Our multianalytical approach integrated synchrotron micro-X-ray fluorescence (μ-XRF) mapping of pyrite grains with electron probe microanalysis and laser ablation-inductively coupled plasma-mass spectrometry data, and sulfur isotope determinations using secondary ion mass spectrometry (SIMS) complemented with bulk sulfur isotope analyses of coeval pyrite, chalcopyrite, and anhydrite. Synchrotron μ-XRF elemental concentration maps of individual pyrite grains reveal a strong zonation of Co, Ni, As, and Se. The observed relationships between Ni and Se are interpreted to reflect changes in temperature and redox conditions during ore formation and provide constraints on fluid evolution. Co and Ni concentrations and ratios suggest contributions from magmas of mafic-intermediate composition. Pyrite chemical concentrations reflect potential stratigraphic controls, where the sample from the upper part of the stratigraphy diverges from trends formed by the rest of the sample set from lower stratigraphic levels. The SIMS δ34S values of pyrite (and chalcopyrite) range between –2 up to 10‰, and bulk δ34S values of pyrite range between 4 up to 12‰. The majority of the δ34S analyses, falling between –1 and 2‰, indicate a magmatic source for sulfur and, by inference, for the hydrothermal ore fluid(s). Variation in the δ34S signature can be explained by changes in the redox conditions, fluid sources, and/or the temperature of the hydrothermal fluid. The Se/S ratio combined with δ34S values in pyrite is consistent with mixing between a magmatic-hydrothermal fluid and a fluid with a probable basinal signature. The results of this study are consistent with the hydrothermal fluids responsible for mineralization in the Candelaria-Punta del Cobre district being predominantly of magmatic origin, plausibly from mafic-intermediate magmas based on the Ni-Co content in pyrite. External fluid incursion, potentially from a basinal sedimentary source, occurred late in the evolution of the system, adding additional reduced sulfur as pyrite. There is no evidence to suggest that the late fluid added significant Cu-Au mineralization, but this cannot be ruled out. Finally, the data reveal that trace element ratios coupled with spatially resolved sulfur isotope data in pyrite are powerful proxies to track the magmatic-hydrothermal evolution of IOCG systems and help constrain the source of their contained metals.
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Bäumler, Jörg, J. H. Frederik Falkenburg, Marianke L. J. van Schie, Karoly Szuhai, Martine Pape, Sina Droll, Oliver G. Ottmann, and Bart Nijmeijer. "Establishment and Characterization of a tel/abl Rearrangement Responsible for Imatinib Sensitivity in bcr/abl Negative Acute Lymphoblastic Leukemia." Blood 110, no. 11 (November 16, 2007): 4280. http://dx.doi.org/10.1182/blood.v110.11.4280.4280.
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Abstract Proliferation of Philadelphia (Ph) positive acute lymphoblastic leukemia (ALL) cells is driven by the bcr/abl oncoprotein which renders transformed cells independent of exogeneous growth factors. Bcr/abl can be targeted by fusion tyrosine kinase inhibitors such as imatinib. ALL is a heterogenous disease. Some cases of Ph negative ALL may be driven by oncogenic fusion kinases other than bcr/abl, with or without involvement of the abl-gene. Such kinases may also be susceptible to targeted inhibitors. At present however, few of such fusion kinases are known. This may be due to the lack of reliable in vitro culturing systems for primary ALL cells. Because of this, only a limited number of ALL cell lines are available to screen for alternative oncogenic fusion kinases. We have recently established an in vitro culturing system in which continuous proliferation (>1 year) was thus far induced in 11 out of 22 primary ALL samples, in the absence of exogenously added growth factors. Five of these 11 cultures were Ph negative by cytogenetics and bcr/abl negative by RT-PCR. Therefore, we first screened these lines for sensitivity to imatinib. One of the 6 Ph negative cell lines, LeidenALL-VG, derived from a 30-year old patient with Ph chromosome negative common ALL, displayed sensitivity to imatinib with an IC50 of 0.1 μM, comparable to the sensitivity of the bcr/abl positive cell lines. RT-PCR with primers specific for tel and abl revealed tel/abl fusion transcripts. Sequencing of the amplicons showed two splice variants of tel-abl: tel4/abl2 and tel5/abl2. Multicolor FISH based karyotyping using COBRA-FISH did not provide evidence for the suggested t(9;12) translocation, indicating cryptic tel/abl rearrangement. To map cryptic genomic aberrations, an array-comparative genomic hybridization array (array-CGH) was performed. A region at 9q34 spanning two array clones was gained (clones RP11-83J21 and RP11-143H20), corresponding with gain of a 300-1300 kb region containing the distal part of the abl gene. A region at 12p13 spanning one array clone was lost (clone RP11-59H1) corresponding with loss of a 1150 to 1750 kb region directly centromeric to the tel gene. To localize cryptic tel/abl rearrangement, fluorescent in situ hybridization (FISH) was performed using the distal tel and abl probes identified by array-CGH, as well as the clones proximal to these regions. FISH revealed an additional distal abl signal, co-localized with the proximal tel signal, on the short arm of an otherwise normal looking chromosome 12. With this, tel/abl rearrangement in LeidenALL-VG cells was characterized as a micro-insertion of one additional distal abl region into the tel region of a normal chromosome 12. Tel/abl rearrangement and imatinib sensitivity were confirmed in the primary cells. These results suggest that our serum-free approach to in vitro culture of primary ALL cells, in combination with molecular karyotyping tools such as array-CGH and COBRA-FISH, may allow identification and characterization of otherwise un-identified chromosomal aberrations, such as the cryptic tel/abl translocation illustrated here, that may be targeted by kinase inhibitors such as imatinib.
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Tolar, Jakub, Alma J. Nauta, Mark J. Osborn, Angela Panoskaltsis-Mortari, Ron T. McElmurry, Scott Bell, Lily Xia, et al. "Osteosarcoma Derived from Cultured Mesenchymal Stem Cells." Blood 108, no. 11 (November 16, 2006): 2554. http://dx.doi.org/10.1182/blood.v108.11.2554.2554.
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Abstract The beneficial effects of Mesenchymal Stem Cells (MSC) are being tested clinically in attempts to improve hematopoietic engraftment, to treat osteogenesis imperfecta, graft-versus-host disease and autoimmune diseases, and to deliver therapy for malignancies. In early reports, phase I clinical studies have not been associated with toxicities. To study the biodistribution of MSC, we labeled adult murine C57BL/6 MSC with firefly luciferase and DsRed2 fluorescent protein using non-viral Sleeping Beauty transposons, and co-infused labeled MSC with bone marrow into irradiated allogeneic recipients. Using in vivo whole body imaging, luciferase signals were shown to be increased between weeks 3 and 12. Unexpectedly, some mice with the highest luciferase signals died and all surviving mice developed foci of sarcoma in lungs. Two mice also developed sarcomas in their extremities. Infusion of MSC-derived sarcoma cells resulted in malignant lesions in secondary recipients. Common cytogenetic abnormalities were identified in tumor cells isolated from different animals. Mapping of the Sleeping Beauty transposition insertion sites did not identify an obvious transposon-related genetic abnormality. Importantly, the original MSC cultures not labeled with transposons, as well as cultured MSC independently isolated from the bone marrow of both BALB/c and C57BL/6 mice showed cytogenetic aberrations after several passages in vitro. Even though not all MSC cultures formed tumors upon in vivo injection, these data indicate that MSC transformation was neither strain-specific nor a rare event following ex-vivo expansion. Karyotype analyses using fluorescence in situ hybridization with spectral karyotyping (SKY) as well as combined binary ratio labeling of nucleic acid probes (COBRA) showed clonal evolution of transformed MSC suggesting that the critical transformation event(s) occurred before MSC infusion. Collectively, we describe cytogenetic instability of murine MSC isolated in two independent laboratories, their cellular transformation, and potential for sarcoma formation. While the growth characteristics of human and murine MSC are not identical and murine cells are more prone to undergo immortalization and transformation in culture than human cells, our study highlights the importance of quality control measures needed for ongoing and future clinical trials using human MSC.
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Anggraini, Rizky Mayang. "Developing A Module on Sound Wave of Solid, Liquid, and Gas Substances through Problem Solving Model with Matlab Simulation on Wave and Optical Courses." Jurnal Pendidikan Fisika 7, no. 2 (May 10, 2019): 173–82. http://dx.doi.org/10.26618/jpf.v7i2.1996.
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This study aims to: (1) to find out the results of the products developed and (2) to find out the perceptions of students regarding the Sound Wave module in Solid, Liquid and Gas Substances developed. This research is research and development (R D) which refers to the model proposed by Thiagarajan. The feasibility of the media is validated by material experts and media experts. Subjects The trial of this study was 25 students of the University of Jambi Physics Education in 2016. The research data is in the form of module validation values by material and media experts, as well as the results of student perceptions of the module. Based on the results of data analysis, it was concluded that the assessment of wave solving and problem-solving optics modules was declared feasible with very good categories, namely with the results of material expert validation of 92%, the value of media expert validation was 86.5%. The results of the analysis of student perception data show that the print module seen from the aspect of the module cover design obtained an average percentage of 83%, from the design aspects in the module obtained an average percentage of 82%, from the presentation aspects of the module material obtained an average percentage amounting to 84.5%, from the aspect of Probem Solving obtained a percentage of 81%, and from the language aspect in the module obtained an average percentage of 84.25%. Based on these results it can be concluded that the Problem Solving-based print module on Sound Wave material in Solid, Liquid, and Gas Waves and Optics courses developed is suitable to be used as one of the learning media that can be used in the implementation of Wave and Optical subject learning.Keywords: Development, modul, Problem Solving Model, 4D model, Sound WavePenelitian ini bertujuan untuk: (1) untuk mengetahui hasil dari produk yang dikembangkan dan (2) untuk mengetahui persepsi mahasiswa mengenai modul Gelombang Bunyi pada Zat Padat, Cair dan Gas yang dikembangkan. Penelitian ini merupakan penelitian dan pengembangan (RD) yang mengacu pada model yang dikemukakan oleh Thiagarajan. Kelayakan media divalidasi oleh ahli materi dan ahli media. Subjek Uji coba penelitian ini adalah mahasiswa Pendidikan Fisika Universitas Jambi angkatan 2016 sebanyak 25 orang. Data hasil penelitian berupa nilai validasi modul oleh ahli materi dan media, serta hasil persepsi mahasiswa mengenai modul. Berdasarkan hasil analisis data disimpulkan bahwa Penilaian modul Gelombang dan Optik berbasis problem solving dinyatakan layak dengan kategori sangat baik yaitu dengan nilai hasil validasi ahli materi sebesar 92%, nilai hasil validasi ahli media sebesar 86,5%. Hasil analisis terhadap data persepsi mahasiswa ini menunjukkan bahwa modul cetak dilihat dari aspek desain cover modul diperoleh persentase rata-rata sebesar 83%, dari aspek desain dalam modul diperoleh persentase rata-rata sebesar 82%, dari aspek penyajian materi modul diperoleh persentase rata-rata sebesar 84,5%, dari aspek Probem Solving diperoleh persentase sebesar 81%, dan dari aspek kebahasaan dalam modul diperoleh persentase rata-rata sebesar 84,25%. Berdasarkan hasil tersebut dapat disimpulkan bahwa modul cetak berbasis Problem Solving pada materi Gelombang Bunyi pada Zat Padat, Cair, dan Gas mata kuliah Gelombang dan Optik yang dikembangkan layak digunakan sebagai salah satu media pembelajaran yang dapat digunakan pada pelaksanaan pembelajaran mata kuliah Gelombang dan Optik..Kata kunci: Pengembangan, Modul, Model Problem Solving, model 4D, Gelombang Bunyi
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Argüelles Díaz, Katia María, Jesús Manuel Fernández Oro, and Eduardo Blanco Marigorta. "Extended Angular Range of a Three-Hole Cobra Pressure Probe for Incompressible Flow." Journal of Fluids Engineering 130, no. 10 (September 4, 2008). http://dx.doi.org/10.1115/1.2969457.
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This paper analyzes the operative characteristics of a three-hole cobra type probe especially designed to attain an angular range higher than 180deg for planar turbulent flows. A new calibration and data reduction method are also introduced, discriminating three different zones inside the angular range of the calibration. This methodology improves the probe performance, extending its operative angular range from the typical ±30degto±105deg. In addition, the transmission of the uncertainty—from the pressure measurements to the flow variables—is estimated, showing reasonably low levels for the whole angular range. Furthermore, the sensibility of the probe calibration to the Reynolds number and the pitch angle is considered, and the influence of the turbulence level is outlined. Regarding these factors, the probe precision in the extended angular range is found to be similar to that of the traditional range. Finally, the probe is tested in a flow field with large variations of the incidence angle, and the results obtained with the new method are compared to those given by the traditional calibration.
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Shahabuddin, M. "Single-Phase Flow Analysis: An Attempt to Mitigate Particle Deposition on the Glass Window of a Fluidized Bed Solar Receiver." Journal of Solar Energy Engineering 138, no. 4 (April 19, 2016). http://dx.doi.org/10.1115/1.4033068.
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The problem of particle deposition on the glass window of a solar receiver has restricted its continuous operation by reducing solar radiation transmission. A rigorous attempt has been made in this analysis by exploring the understanding of particle deposition mechanisms and their mitigating strategies. A simplified form of a fluidized bed solar receiver (FBSR) having the same flow phenomena of FBSR is chosen for the numerical analysis. In the numerical analysis, the turbulent flow in the receiver is investigated by renormalized group (RNG) theory based k–ε models. The validation of the numerical model is carried out by measuring the turbulent flow properties using a turbulent flow instrumentation (TFI) Cobra probe. The results of this analysis revealed that mass flow into the secondary concentrator of the receiver was reduced significantly when the ratio between the outlets and inlet areas was 0.5, and the ratio between the aperture and receiver diameter was 0.41. When using window shielding jets, only 5% of the inlet mass as a window jet was sufficient to prevent any particle deposition on the glass window, however, the number of jets was found to be an important factor. At a constant mass flow rate, increasing the number of window shielding jets reduced the suction pressure from the core to the aperture, which helped to restrict the inlet flow in the secondary concentrator.
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Yu, Kehui, Xuhui He, Chenzhi Cai, Lei Yan, and Yunfeng Zou. "Aerodynamic characteristics of trains on a viaduct with non-uniform cross-section under crosswinds by wind tunnel tests." Advances in Structural Engineering, January 6, 2021, 136943322098609. http://dx.doi.org/10.1177/1369433220986099.
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This paper focuses on the aerodynamic characteristics of trains on a non-uniform double-track railway bridge under crosswinds through a scaled 1:40 sectional model wind tunnel test. Pressure measurements of five cross-sections of two types of trains, one with round roof and one with blunt roof, at the upstream and downstream tracks of the bridge were conducted under crosswinds with wind attack angles between −12° and 12°. The mean wind speed and turbulence intensity profiles around the windward surface of the train in the downwind and upward directions were also measured using cobra probe to obtain the boundary layer above the bridge surface. The results show that the shapes of train and bridge, as well as the wind attack angle, affect the aerodynamic characteristic of the train on the non-uniform bridge girder. The mean and fluctuating pressure coefficients are similar for all five cross-sections of the trains while the train is at the upstream track. However, when the train is at the downstream track, the extreme mean and fluctuating pressure coefficients around the windward and top surfaces of each cross-section on the train are different. At the downstream track, the mean wind speed profile and the turbulence intensity profile around the top of the train vary dramatically due to the separation flow caused by the leading edge of the bridge girder.
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Schölch, M., and S. Wilke. "Verfahren zur Bestimmung von Strömungsrichtung, statischem Druck und Gesamtdruck mit einer Kobrasonde / Method for determining static and dynamic pressure and the direction of velocity vector with a cobra probe." tm - Technisches Messen 58, JG (January 1991). http://dx.doi.org/10.1524/teme.1991.58.jg.287.
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Tewari, Brij B., D. Usmanali, Glen A. Soobramani, Sharlene Roberts, Mancy Abbas, Tricia Grant, Ashish K. Tiwari, Shivanand Singh, and Marc V. Boodhoo. "REVISIONES CRÍTICAS DE ESTABILIDAD Y DE POTENCIAL DE FOTOSENSIBILIZADOR DE FERROCIANUROS METÁLICOS: UN POSIBLE MINERAL PREBIÓTICO PARTE III." Revista Boliviana de Química 1, no. 36.1 (April 30, 2019). http://dx.doi.org/10.34098/2078-3949.36.1.3.
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Los ferrocianuros de cobre, lantano, mercurio, molibdeno, plata, titanio y zinc se sintetizaron y caracterizaron mediante análisis elemental y estudios espectrales. La estabilidad de los ferrocianuros metálicos sintetizados se registró en calor (varias temperaturas), varias concentraciones de ácidos (HCl, H2SO4, HNO3, CH3 COOH) varias concentraciones de bases (NaOH, KOH, NH4OH), y en agua de mar y de grifo. Todas las estabilidades se registraron a temperatura ambiente y de ebullición. La estabilidad de los ferrocianuros metálicos sintetizados también se registró en presencia de radiación visible y ultravioleta. El potencial oxidante y fotosensibilizante de los ferrocianuros metálicos sintetizados se probó con yoduro de potasio y la solución de almidón recién preparada indicó que el ferrocianuro de cobre es un posible oxidante fuerte y fotosensibilizador. Se descubrió que los ferrocianuros de molibdeno, mercurio y tungsteno actúan como oxidante débil y fotosensibilizador. El lantano y el ferrocianuro de zinc no mostraron ningún potencial oxidante y fotosensibilizante.
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Gil, N., C. J. Baker, C. Roberts, and A. Quinn. "Passenger Train Slipstream Characterization Using a Rotating Rail Rig." Journal of Fluids Engineering 132, no. 6 (May 19, 2010). http://dx.doi.org/10.1115/1.4001577.
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This paper presents the results of a new experimental technique to determine the structure of train slipstreams. The highly turbulent, nonstationary nature of the slipstreams make their measurement difficult and time consuming as in order to identify the trends of behavior several passings of the train have to be made. This new technique has been developed in order to minimize considerably the measuring time. It consists of a rotating rail rig to which a 1/50 scale model of a four car high speed train is attached. Flow velocities were measured using two multihole Cobra probes, positioned close to the model sides and top. Tests were carried out at different model speeds, although if the results were suitably normalized, the effect of model speed was not significant. Velocity time histories for each configuration were obtained from ensemble averages of the results of a large number of runs (of the order of 80). From these it was possible to define velocity and turbulence intensity contours along the train, as well as the displacement thickness of the boundary layer, allowing a more detailed analysis of the flow. Also, wavelet analysis was carried out on different runs to reveal details of the unsteady flow structure around the vehicle. It is concluded that, although this methodology introduces some problems, the results obtained with this technique are in good agreement with previous model and full scale measurements.