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1
Görbitz, Carl Henrik, Jan Christian Paulsen, and Jon Borgersen. "Redetermined crystal structure of β-DL-methionine at 320 K." Acta Crystallographica Section E Crystallographic Communications 71, no. 6 (May 13, 2015): o398—o399. http://dx.doi.org/10.1107/s2056989015008749.
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The structure of β-DL-methionine, C5H11NO2S, in the space groupC2/c, is here confirmed to be fully ordered all the way up to the phase transition at approximately 326 K, where displacive sliding of molecular bilayers gives the disorderedP21/cα form [data at 340 K; Görbitz (2014).Acta Cryst.E70, 341–343]. The geometry of hydrogen bonds in LD–LD hydrogen-bonding patterns [Görbitzet al.(2009).Acta Cryst.B65, 393–400] at the hydrophilic core of each molecular bilayer are virtually unperturbed by the phase shift, but the C—C—S—C torsion angle of the side chain changes fromtransat 320 K togauche+ for the major conformation at 340 K.
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Barron, G. L. "Microcolonies of bacteria as a nutrient source for lignicolous and other fungi." Canadian Journal of Botany 66, no. 12 (December 1, 1988): 2505–10. http://dx.doi.org/10.1139/b88-340.
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Under low nutrient conditions hyphae of certain fungi are strongly attracted to microcolonies of bacteria belonging to the genera Pseudomonas and Agrobacterium. Hyphae of the fungi penetrate the microcolonies and proliferate to produce coral-loid, haustorial-like masses of absorptive hyphae. The bacteria in the colonies are lysed and the contents apparently absorbed as a nutrient source by the fungi. The four fungi that demonstrated this capability were Agaricus brunnescens (= A. bisporus), Coprinus quadrifidus, Lepista nuda, and Pleurotus ostreatus. Approximately 100 additional species belonging to the Basidiomycota, Oomycota, Zygomycota, Deuteromycota, or Ascomycota were also tested, but none were found capable of attacking and digesting bacterial colonies in this way.
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Chiquet, M., L. Masuda-Nakagawa, and K. Beck. "Attachment to an endogenous laminin-like protein initiates sprouting by leech neurons." Journal of Cell Biology 107, no. 3 (September 1, 1988): 1189–98. http://dx.doi.org/10.1083/jcb.107.3.1189.
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Leech neurons in culture sprout rapidly when attached to extracts from connective tissue surrounding the nervous system. Laminin-like molecules that promote sprouting have now been isolated from this extracellular matrix. Two mAbs have been prepared that react on immunoblots with a approximately equal to 220- and a approximately equal to 340-kD polypeptide, respectively. These antibodies have been used to purify molecules with cross-shaped structures in the electron microscope. The molecules, of approximately equal to 10(3) kD on nonreducing SDS gels, have subunits of approximately equal to 340, 220, and 160-180 kD. Attachment to the laminin-like molecules was sufficient to initiate sprouting by single isolated leech neurons in defined medium. This demonstrates directly a function for a laminin-related invertebrate protein. The mAbs directed against the approximately equal to 220-kD chains of the laminin-like leech molecule labeled basement membrane extracellular matrix in leech ganglia and nerves. A polyclonal antiserum against the approximately equal to 220-kD polypeptide inhibited neurite outgrowth. Vertebrate laminin did not mediate the sprouting of leech neurons; similarly, the leech molecule was an inert substrate for vertebrate neurons. Although some traits of structure, function, and distribution are conserved between vertebrate laminin and the invertebrate molecule, our results suggest that the functional domains differ.
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Gonçalves Maciel, Luiz Henrique, Cosmo Vieira da Rocha Neto, Yasmin Ferreira Martins, Francielen de Azevedo Furtado, Pâmela Cunha Teixeira, Maianne Yasmin Oliveira Dias, Yanka Karolinna Batista Rodrigues, et al. "Prevalence of arboviruses and other infectious causes of skin rash in patients treated at a tertiary health unit in the Brazilian Amazon." PLOS Neglected Tropical Diseases 16, no. 10 (October 13, 2022): e0010727. http://dx.doi.org/10.1371/journal.pntd.0010727.
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Background In the clinical course of diseases such as arboviruses, skin rashes may appear, as is often seen in other infectious diseases. The aim of this study was to estimate the prevalence of arboviruses and other infectious causes of skin rash in a tertiary health unit in Manaus, Amazonas state, Western Brazilian Amazon Methodology/Principal findings This was a cross-sectional study of patients presenting with rash who sought care at Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD) from February 2018 to May 2019. Individuals of either gender, aged over 18 years, were invited to participate voluntarily. Infection by Zika virus (ZIKV), dengue virus (DENV), chikungunya virus (CHIKV), Mayaro virus (MAYV), Oropouche virus (OROV) and measles was evaluated using RT-qPCR (real-time polymerase chain reaction). Immunodiagnostic tests for EBV, CMV, HIV, syphilis, rubella and measles were also performed. A total of 340 participants were included, most were female (228, 67.1%) with an average age of 36.5 years (SD ± 12.2 years). The highest prevalence was of ZIKV monoinfections (65.3%, 222/340), followed by DENV (0.9%, 3/340) and CHIKV infection (0.3%, 1/340). No cases of MAYV, OROV or rubella were found. Other causes of skin rash were detected: measles (2.9%, 10/340), parvovirus B19 (0.9% 3/340), HIV (0.3%, 1/340) and syphilis 0.6% (2/340). The co-infections identified were ZIKV+HIV (0.3%, 1/340), ZIKV+measles (0.3%, 1/340), ZIKV+parvovirus B19 (0.3%, 1/340), ZIKV+EBV (0.3%, 1/340), EBV+parvovirus B19 (0.3%, 1/340), CMV+parvovirus B19 (0.6%, 2/340), CMV+syphilis (0.3%, 1/340), ZIKV+EBV+parvovirus B19 (0.3%, 1/340) and CMV+EBV+parvovirus B19 (0.9%, 3/340). Approximately one quarter of patients had no defined cause for their skin rash (25.3%, 86/340). Conclusions Despite the benign clinical evolution of most of the diseases diagnosed in this series of cases, syndromic surveillance of diseases such as syphilis and HIV are of utmost importance. Periodic serosurveillance might also aid in evaluating the trends of endemic diseases and eventual outbreaks.
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Choi, C. S., and H. J. Prask. "Texture of extruded uranium alloy by neutron diffraction." Journal of Applied Crystallography 18, no. 6 (December 1, 1985): 413–18. http://dx.doi.org/10.1107/s0021889885010639.
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The pole-density distributions of two hydrostatically extruded samples, a U–0.75 wt.% Ti alloy and a U–0.75 wt % Ti/W composite alloy, were studied by neutron diffraction methods. Analysis of U 112, U 131 and U 111 pole figures revealed that the α-U phases of both samples possess a [010]/[340] duplex fiber texture with a probability ratio of approximately 2.8:1 in favor of the [010] direction. The W phase of the composite sample had a [110] fiber texture. The orientation distribution profiles of the fiber axes obtained from the rocking curves (as a function of the tilt angle) were represented best by a Gaussian–Lorentzian combination function. The full widths at half maximum of the distributions were approximately 21, 11, and 5° for the U [010], U [340] and W [110] fiber axes, respectively.
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GIS, Wojciech, Maciej GIS, Piotr WIŚNIOWSKI, and Mateusz BEDNARSKI. "Comparative tests of a passenger car with compression ignition engine on chassis dynamometer during NEDC and WLTC tests and during RDE road test." Combustion Engines 178, no. 3 (July 1, 2019): 228–34. http://dx.doi.org/10.19206/ce-2019-340.
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Air pollution is a challenge for municipal authorities. Increased emission of PM10 and PM 2.5 particles is particularly noticeable in Poland primarily the autumn and winter period. That is due to the start of the heating season. According to the above data, road transport accounted for approximately 5% of the creation of PM10 particles, ca. 7% of PM2.5 and approximately 32% for NOx. In Poland, suspended particles (PM10 and PM2.5) cause deaths of as many as 45,000 people a year. The issue of smog also affects other European cities. Therefore, it is necessary to undertake concrete efforts in order to reduce vehicle exhaust emissions as much as possible. It is therefore justifiable to reduce the emission of exhaust pollution, particularly NOx, PM, PN by conventional passenger cars powered by compression ignition engines. Emissions by these passenger cars have been reduced systematically. Comparative tests of the above emission of exhaust pollution were conducted on chassis dynamometer of such passenger car in NEDC cycle and in the new WLTC cycle in order to verify the level of emissions from this type of passenger car. Measurements of fuel consumption by that car were also taken. Emission of exhaust pollution and fuel consumption of the this car were also taken in the RDE road test.
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Frego, K. A., and R. J. Staniforth. "Factors determining the distribution of Opuntia fragilis in the boreal forest of southeastern Manitoba." Canadian Journal of Botany 63, no. 12 (December 1, 1985): 2377–82. http://dx.doi.org/10.1139/b85-340.
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Opuntia fragilis (Nutt.) Haw. is restricted to south-facing rock outcrops on the shores of certain rivers and lakes in the boreal forest of southeastern Manitoba. Limitations in propagule dispersal, establishment, and maintenance were studied at Bird River (50°25′ N, 95°41′ W) between October 1979 and October 1982. Propagules studied were stem units (pads) because this cactus propagates entirely by vegetative means in this region. Mature terminal pads broke off most easily in the late spring while turgid and rolled downhill (geochory), thus establishing new plants locally. Some pads fell into the river and could float long distances (hydrochory) before being washed ashore. Perhaps less frequently, pads were dispersed over long distances on animals (epizoochory). Marked pads placed in potential habitats showed significantly greater establishment (α = 0.05) on south-facing outcrops than on north-facing or forest sites. Censuses (1979–1982) of an established colony indicated that pad number was increasing by 51% per year. Approximately 6% of the pads were dispersed from the outcrop. The present distribution of O. fragilis appears to be both habitat and dispersal limited.
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Zivelin, Ariella, Ronit Mor-Cohen, Victoria Kovalsky, Nurit Kornbrot, Jacqueline Conard, Flora Peyvandi, Paul A. Kyrle, et al. "Prothrombin 20210G>A is an ancestral prothrombotic mutation that occurred in whites approximately 24 000 years ago." Blood 107, no. 12 (June 15, 2006): 4666–68. http://dx.doi.org/10.1182/blood-2005-12-5158.
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Abstract Prothrombin 20210G>A and factor V Leiden are common prothrombotic mutations in whites for which founder effects have been established. In this study, we analyzed the frequencies of 5 single nucleotide polymorphisms (SNPs) and 9 microsatellites flanking the prothrombin gene (F2) in 88 homozygotes for 20210A and 66 homozygotes for 20210G. For estimating the age of the prothrombin 20210G>A mutation, we used the DMLE+2.0 program, which analyzed linkage disequilibria between the mutation and the multiple markers that had been assessed. This analysis yielded an age estimate of 23 720 years (95% credible set, 19 080-31 340 years). A similar analysis by the DMLE+2.0 program was performed on 5 SNPs from previously studied homozygotes for factor V Leiden and controls that yielded an age estimate of 21 340 years (95% credible set, 16 880-29 480 years). The occurrence of the 2 mutations in whites toward the end of the last glaciation and their presently wide distribution in whites suggest selective evolutionary advantages for which some evidence was reported (diminished blood loss) or is controversial (protection against infections).
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Erwin, Diane M., and Ruth A. Stockey. "Permineralized monocotyledons from the Middle Eocene Princeton chert (Allenby Formation) of British Columbia: Alismataceae." Canadian Journal of Botany 67, no. 9 (September 1, 1989): 2636–45. http://dx.doi.org/10.1139/b89-340.
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One small monocotyledon petiole, 1.8 × 1.5 mm wide, has been recovered from the Princeton chert in the Middle Eocene Allenby Formation, British Columbia. The petiole, rectangular in transverse outline, shows approximately 36 circular to oval-shaped vascular bundles within aerenchymatous ground tissue that includes tannin cells. The epidermis is underlain by a discontinuous hypodermis of thick-walled, pitted cells. Vascular bundles are in five series: (I) a median U-shaped arc of 11 – 13 bundles; (II) an abaxial arc of 6 bundles located below the main arc; (III) two short abaxial arcs of 3 bundles each; (IV) 2 bundles just below the abaxial surface; and (V) an adaxial series of 7 bundles that show an inverse orientation to those bundles in series I–IV. Larger bundles are collateral, with a protoxylem lacuna encircled by a ring of 9 – 14 thin-walled parenchyma cells, a relatively well-developed phloem strand, and one to three thin-walled metaxylem elements. Based on bundle arrangement, orientation, and morphology, the fossil petiole most closely resembles those of the Butomaceae and Alismataceae. This new species, Heleophyton helobiaeoides Erwin and Stockey gen. et sp.nov., in the Princeton chert flora, documents the presence of the Alismataceae in the Middle Eocene of western North America and provides further evidence that the locality represents an ancient aquatic ecosystem.
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Thomas, Delma P., and Dianne E. Godar. "Ultraviolet-A1 radiation induces immediate apoptosis in a human leukemia T-cell line (Jurkat)." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 206–7. http://dx.doi.org/10.1017/s0424820100168761.
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We previously reported that radiation from all three ultraviolet (UV) waveband regions, i.e., UVA (320-400 nm), UVB (290-320 nm), and UVC (200-290 nm) cause either immediate apoptosis (UVA1, 340-400 nm) or delayed apoptosis (UVB or UVC) in L5178Y-R murine lymphoma cells. We coined the terms immediate and delayed apoptosis to help distinguish the mechanistic differences between apoptosis and programmed cell death (or delayed apoptosis) which have been incorrectly used as synonyms. This confusion occurred primarily because these two cell death mechanisms are morphologically identical. However, kinetics can be used to discriminate between these two cell death mechanisms. Immediate apoptosis occurs within 4 h following exposure, whereas delayed apoptosis requires 20-34 h to display similar morphological changes. In this investigation, we explored the possibility that the UVA1-induced immediate apoptotic mechanism might be a common phenomenon by examining a human acute T-cell leukemia cell line (Jurkat).Four hours following either sham- or UVAl-exposure to 250, 500, or 750 kJ/m2 (resulting in approximately 50, 80 and 90% reproductive death, respectively) from a 200 W/m2 sunlamp (>340 nm), Jurkat T-cells (clone E6-1, American Type Culture Collection, Rockville, MD) were processed for transmission electron microscopy (TEM) using a procedure described previously.
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Linder, M. W., and R. Valdes. "Mechanism and elimination of aspirin-induced interference in Emit II d.a.u. assays." Clinical Chemistry 40, no. 8 (August 1, 1994): 1512–16. http://dx.doi.org/10.1093/clinchem/40.8.1512.
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Abstract The presence of salicylates in urine reduces the signal in Emit assays (Syva), potentially yielding false-negative drugs-of-abuse screening results. We demonstrate that the principal urinary metabolite of salicylate, salicyluric acid (SUA; 2-hydroxybenzoylaminoacetic acid), interferes with the measurement of NADH formed in the assay by reducing the molar absorptivity of NADH at 340 nm. Thus, for a given concentration of d.a.u. analyte the change in absorbance over the assay time interval is less in the presence of SUA. With the Emit cocaine assay on the Hitachi 704 analyzer, the rate of absorbance change (delta AR) monitored at 340 nm for a specimen containing approximately 270 micrograms/L benzoylecgonine (BE) was 57 +/- 1.9 mA/min without SUA and 29 +/- 2.7 mA/min with 5 g/L SUA (n = 20). In contrast, delta AR determined at 376 nm was 18.6 +/- 0.5 mA/min with and 17.9 +/- 0.8 mA/min without 5 g/L SUA (n = 20). Measuring the Emit assay signal at wavelengths where SUA has no absorbance (376 nm) eliminates the interference due to SUA while maintaining the precision of the assay near the cutoff concentration for BE (300 micrograms/L).
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Suki, B., R. H. Habib, and A. C. Jackson. "Wave propagation, input impedance, and wall mechanics of the calf trachea from 16 to 1,600 Hz." Journal of Applied Physiology 75, no. 6 (December 1, 1993): 2755–66. http://dx.doi.org/10.1152/jappl.1993.75.6.2755.
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Propagation of waves in the airways is important in flow limitation as well as in oscillation mechanics. In five excised calf tracheae, we measured phase propagation velocity (c) and input impedance with open (Zop) or closed end (Zcl) for frequencies (f) between 16 and 1,600 Hz at two axial tensions [nonstretched (TN) and stretched (TS); TS > TN]. From 16 to 64 Hz, c slightly increased because of the viscoelastic properties of the wall tissues. Between 64 and 200 Hz, c was relatively constant and less than the free-field speed of sound (c0 = 340 m/s), with values smaller at TS (140 +/- 39 m/s) than at TN (172 +/- 35 m/s). Above 200 Hz, c exceeded c0 and displayed two maxima at approximately 300 and approximately 700 Hz, with values of approximately 360 and approximately 550 m/s, respectively. For f > 1,400 Hz, c approached c0. We provide evidence that the two maxima in c were the result of the two-compartment behavior of the wall tissues, i.e., the separate cartilaginous and soft tissues. A nonrigid tube model with its wall impedance composed of two series resistance, compliance, and inertance pathways in parallel simultaneously fits c, Zop, and Zcl well and hence provides a link among these data. By use of the relationship between volumetric wall parameters and the tracheal geometry, separate material properties such as viscosity and Young's modulus of both the soft tissue (approximately 1 cmH2O.s and approximately 0.26 x 10(4) cmH2O, respectively) and the cartilage (approximately 3.7 cmH2O.s and approximately 2 x 10(4) cmH2O, respectively) were estimated. These results indicate that measures of c and Zop or Zcl data over these frequencies provide information about the dynamic mechanical properties of both the soft tissue and cartilage in the airway walls.
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Wright, David A., Rodger Dawson, and Celia E. Orano-Dawson. "Shipboard Trials of Menadione as a Ballast Water Treatment." Marine Technology and SNAME News 44, no. 01 (January 1, 2007): 68–76. http://dx.doi.org/10.5957/mt1.2007.44.1.68.
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Shipboard trials of a chemical ballast water treatment, menadione (methyl 1,4-naphthoquinone), were conducted in Baltimore Harbor, Maryland, under normal ballasting conditions at a flow rate of 340 tonne h002D1. Several different concentrations and formulations of menadione were tested. Most proved effective at controlling zooplankton to international standards at approximately 2 mgL002D1 and completely inhibited the growth of phytoplankton at this, or lower, concentrations.
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Challenger, Gregory E., Gary S. Mauseth, and Ileana Rhodes. "Residual Gasoline in a Turbulent Pacific Northwest Stream Following Release and Subsequent Ignition." International Oil Spill Conference Proceedings 2001, no. 1 (March 1, 2001): 283–90. http://dx.doi.org/10.7901/2169-3358-2001-1-283.
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ABSTRACT Approximately 5,500 barrels of unleaded gasoline escaped from a ruptured pipeline in Bellingham, Washington on June 10, 1999. The majority of the product entered Whatcom Creek, with a flow of approximately 0.3 m3/s (10 cfs). The gasoline affected approximately 4.8 km (3 miles) of the creek. After a period of approximately 4 hours, the product contacted an ignition source. Twenty hours following the incident, a water-sampling program at 8 stations in Whatcom Creek and 12 stations in Bellingham Bay was implemented. Ultimately, nearly 400 water-column samples were analyzed for gasoline range hydrocarbons (GRHs), including BTEX compounds and MTBE. Samples were collected every 4 hours for the first 5 days, daily for the next 17 days, and 16 of the following 32 days. Initial maximum concentrations found in water samples were 20,800 ug/L GRH, 2,600 ug/L total xylenes, 1,300 ug/l toluene, 340 ug/L ethylbenzene, 110 ug/L benzene, and 6.9 ug/L MTBE. Product concentrations in the stream declined rapidly. Within 140 hours of the incident, GRHs subsided two orders of magnitude. Instream waters met State of Washington Groundwater Cleanup Standards (Washington Administrative Code, Chapter 173–340.) in an average of 131 hours from the time of the release for benzene, 127 hours for ethylbenzene, 66 hours for toluene, and 207 hours for xylene. Volatilization of BTEX during transport downstream was evidenced by a consistent gradient of reduced concentrations with distance from the source. Sediment pore water and bulk sediments were also sampled. Initial pore-water GRH ranged widely from nondetect to 110,000 ug/L. GRH in bulk sediment samples ranged from nondetect to 447,000 ug/L. A remediation program was conducted to release product trapped in the streambed that reduced contaminants to levels deemed acceptable by a risk-based approach for survival of salmonid fry populations. This approach and resultant guidelines are described.
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Kawashima, Yusuke, Masaaki Miyakoshi, Yoshihiro Kawabata, and Hiroko Indo. "Normal Cone beam Computed Tomography image findings of nutrient canals in 340 pediatrics." American Journal of Diagnostic Imaging 9, no. 2 (2023): 22. http://dx.doi.org/10.5455/ajdi.20221211015927.
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The purpose of this study was to assess normal image findings of mandibular nutrient canals(NCs) using CBCT images, including canal prevalence, number, size of nutrient canal. 340 consecutive pediatric patients were included in this study. Parameters including canal prevalence, number and size (mesial-distal and buccal-lingual diameters) were measured on CBCT axial images. 82.1% were found NCs in the anterior region of the mandible. The mean number of NCs were 1.39 in males and 1.49 in females. However, there were no significant age and gender-related differences in the mean number of NCs. The mean diameter of NCs were approximately 0.6mm in both males and females. However, there was no significant age related differences in the size of NCs in both males and females. In conclusion, this was the first study that described normal CBCT findings of mandibular anterior NCs in pediatrics. The prevalence of accidents or lesions in anterior mandible is low, by preoperative knowledge of the NCs in anterior region of the mandible, complications such as injury to the NCs can be avoided in pediatrics.
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Baird, Mark E., Patrick G. Timko, and Lujia Wu. "The effect of packaging of chlorophyll within phytoplankton and light scattering in a coupled physical - biological ocean model." Marine and Freshwater Research 58, no. 10 (2007): 966. http://dx.doi.org/10.1071/mf07055.
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A coupled physical–biological model forced with spectrally resolved solar radiation is used to investigate the effect of packaging of pigment and light scattering on physical and biological properties in the open ocean. Simulations are undertaken with three alternate formulations of vertical attenuation, which consider: (1) chlorophyll as dissolved in the water column; (2) chlorophyll packaged into phytoplankton cells with no scattering; and (3) packaged chlorophyll with scattering. In the coupled model, depth-resolved solar heating depends on the vertical profile of phytoplankton concentration, creating a feedback mechanism between the physical and biological states. The particular scenario investigated is a northerly wind off the coast of south-east Australia. The packaging of chlorophyll approximately halves the attenuation rate of 340–500 nm light and a phytoplankton maximum forms ~10 m deeper than in the dissolved chlorophyll case, with a corresponding adjustment of the dissolved inorganic nitrogen and zooplankton fields. Scattering approximately doubles the vertical attenuation of 340–600 nm light, lifting the phytoplankton maximum by ~10 m when compared with the packaged chlorophyll case. Additionally, strong horizontal gradients in chlorophyll distribution associated with filaments of upwelled water inshore of the East Australian Current, when modelled with alternate formulations of vertical light attenuation, result in circulation changes. The explicit representation of the packaging of pigment and light scattering is worth considering in coupled physical–biological modelling studies.
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Abdulhameed, M. K., M. S. Mohamad Isa, Z. Zakaria, I. M. Ibrahim, and Mowafak K. Mohsen. "Radiation pattern control of microstrip antenna in elevation and azimuth planes using EBG and pin diode." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 1 (February 1, 2019): 332. http://dx.doi.org/10.11591/ijece.v9i1.pp332-340.
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An important issue in wireless communication systems, which is related to the antenna gain degradation in case of changing the main direction of the antenna radiation pattern, this variation is not approval in many communications systems. In order to improve antenna radiation performances, Electromagnetic band gap (EBG) - antenna with radiation pattern control capability is presented. Mushroom-like EBG structure for suppressing surface waves has been combined, with the switching diode to produce the radiation pattern control with improving antenna characteristics of gain, directivity and efficiency. EBG of several cells are surrounded the patch antenna and placed symmetrically for the two opposite sides, generating different radiation patterns control ability in both the elevation (E) (-20° < φ < 20°) and azimuth (Z) planes (−18° < θ < 18°). At the ground plane of antenna the diodes have been switched ON and OFF states, the EBG sector properties in stop band (connecting vias) and pass band (disconnecting vias) are altered. Using CST Microwave Studio (CST MWS) the results show the flexibility in radiation pattern control for the Z and E planes using only four diodes. Antenna directivity of 10 dBi, gain 9.86 dB and efficiency 96.5% at the operating frequency of 6 GHz, more results for all direction has been stated in Table1. Significantly, unlike a conventional beam steering, this method does not suffering from gain degradation and the main lobe gain is approximately constant for all steerig angles.
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Burch, Jennie. "The community nurse and stoma care." British Journal of Community Nursing 27, no. 4 (April 2, 2022): 165–68. http://dx.doi.org/10.12968/bjcn.2022.27.4.165.
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Community nurses will have people with a stoma on their caseload, and a reminder about stoma and stoma care will hopefully increase confidence and, subsequently, care. There are approximately 205 000 people in the UK with a stoma; it is a common condition, with approximately one in every 340 people having a stoma. While quality of life with a stoma can be good, problems can occur, such as a leaking appliance that results in skin damage. Skin damage can occur for all people with a stoma, but is more common for people with an ileostomy. Appliance leakage can increase stoma care costs, time, financially as well as a decrease in quality of life, so it is important to be able to address issues when they arise or refer on as necessary.
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Falchook, Gerald Steven, Meredith McKean, William Kevin Kelly, Manish R. Patel, Manojkumar Bupathi, Bobby Chi-Hung Liaw, Benjamin Garmezy, et al. "Phase 1 clinical trial of AMG 340, a prostate-specific membrane antigen (PSMA)-targeted T-cell engager with a novel low-affinity CD3 binding domain designed to mitigate toxicity for the treatment of metastatic castration-resistant prostate cancer (mCRPC)." Journal of Clinical Oncology 42, no. 16_suppl (June 1, 2024): e14587-e14587. http://dx.doi.org/10.1200/jco.2024.42.16_suppl.e14587.
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e14587 Background: PSMA, a transmembrane protein highly expressed on the surface of prostate cancer cells, is a validated target in prostate cancer; however, achieving a favorable therapeutic index has been challenging for PSMA-directed T-cell engagers (TCE’s). AMG 340, a PSMA-targeted TCE with a novel low-affinity CD3 binding domain specifically engineered to mitigate cytokine release syndrome (CRS) toxicity and maintain efficacy was investigated in a phase 1, open-label, dose-escalation study (NCT04740034). Methods: Patients (pts) with mCRPC who had received ≥2 prior lines of therapy were treated with AMG 340 monotherapy (1.5–800 mg intravenously every 3 weeks [Q3W]) during dose escalation. The primary outcome measures were dose-limiting toxicities, treatment-emergent adverse events (TEAEs), and pharmacokinetic profile. Secondary outcomes included prostate antigen specific (PSA) response and objective response per response evaluation criteria in solid tumors (RECIST). Results: As of September 6, 2023, a total of 42 pts (mean ± SD age, 68.5±7.8 years) received AMG 340 step up dosing across 11 cohorts. At doses up to 800 mg Q3W, AMG 340 had a manageable side effect profile. Any grade TEAEs reported in ≥30% of pts included CRS (52%), nausea (52%), vomiting (52%), fatigue (48%), diarrhea (38%), increased aspartate aminotransferase (36%), increased alanine aminotransferase (33%), and hypocalcemia (31%). Treatment-related toxicities included CRS (52%; Grade 1, 26%; Grade 2, 24%; Grade ≥3, 2%) and thrombocytopenia (24%; Grade 2, 10%; Grade ≥3, 14%). Step dosing was implemented at doses >40 mg and successfully mitigated CRS incidence and severity after the first dose. The maximal tolerated dose was not reached, as increasing the dose beyond 800 mg was predicted to minimally increase the potential AMG 340 activity. Exposure increased in an approximately dose-proportional manner with no evidence of clinically significant anti-drug antibodies. AMG 340 demonstrated evidence for pharmacodynamic engagement as shown by cytokine induction. Of the 41 PSA evaluable pts, PSA responses were seen across dose levels (PSA50, n=4), but were not dose dependent. Eight of 42 pts remained on treatment after 6 months. Among 27 RECIST evaluable pts, no RECIST responses were observed (n=14 stable disease, n=0 partial or complete response). Conclusions: Despite reaching high doses, no dose response was observed, and AMG 340 did not generate sufficient clinical activity to warrant further exploration. However, AMG 340 demonstrated manageable CRS toxicity showing that decreased CD3-binding strength mitigates CRS, the main toxicity of TCEs. Clinical studies are ongoing evaluating the PSMA protein as a molecular target for prostate cancer. Clinical trial information: NCT04740034 .
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Teichgräber, B., P. Arendt, H. Brockmann, and F. Obenaus. "Remote control system for the operation of 65 WWTPs." Water Science and Technology 45, no. 4-5 (February 1, 2002): 461–67. http://dx.doi.org/10.2166/wst.2002.0650.
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The present report discusses the monitoring system for approximately 340 facilities for water management of the Emschergenossenschaft and Lippeverband. It is based on the operation control system of the wastewater treatment plants (currently 61) and the pumping stations of the Lippeverband, which has been created since 1985. For the near future, the integration of the plants of the Emschergenossenschaft including storm-water tanks is scheduled. The current connection ratios of the WWTPs which are to be monitored vary between 500 and 1,940,000 Population Equivalents. The data recorded at each plant are transmitted to the allocated catchment area centre and then to the district centres. The encompassing monitoring centre serves the integrated control of all plants. The comprehensive remote control is managed through the presentation of relevant plant-type-specific system parameters. The investment costs of approximatelyt 33,000 €/plant and annual costs of 9,400 €/plant stand against a considerable increase of the operation safety and the reduction of manpower.
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Castagnoli, Steven P., Leslie H. Fuchigami, Tony H. H. Chen, and Liping Zhen. "552 PB 340 DORMANCY DEVELOPMENT AND STRESS TOLERANCE IN `BRAEBURN' AND `FUJI' APPLE NURSERY STOCK." HortScience 29, no. 5 (May 1994): 510e—510. http://dx.doi.org/10.21273/hortsci.29.5.510e.
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Studies were performed on the development of dormancy, cold hardiness, and desiccation tolerance, and the effect of manual defoliation timing on performance of `Fuji' and `Braeburn' apple nursery stock. Dormancy development, response to defoliation, and desiccation tolerance of apple differed from those reported for other temperate woody plant species. Dormancy development in `Fuji' was approximately two weeks ahead of `Braeburn', and was strongly regulated by temperature. Photoperiod had no influence on dormancy development of `Fuji'. Desiccation tolerance of both varieties was greatest just prior to the onset of dormancy and early dormancy. This pattern in the seasonal development of tolerance to desiccation is not typical of temperate woody plant species. Early defoliation was detrimental to performance of `Braeburn', but had little effect on `Fuji'. Early defoliation promoted earlier spring budbreak in `Fuji'. Development of freezing tolerance in both apple varieties was typical of other woody plants, and coincided with the onset of dormancy. Maximum hardiness was achieved after the requirements for dormancy were completely satisfied.
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Malcoci, Iulian. "Sound Reasearch in Precessional Transmission." Applied Mechanics and Materials 657 (October 2014): 584–88. http://dx.doi.org/10.4028/www.scientific.net/amm.657.584.
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Sound may be defined as any pressure variation (in air, water or other medium) that the human ear can detect. Just like dominoes, a wave motion is set off when an element sets the nearest particle of air into motion. This motion gradually spreads to adjacent air particles further away from the source. Depending on the medium, sound propagates at different speeds. In air, sound propagates at a speed of approximately 340 m/s. In liquids and solids, the propagation velocity is greater 1500 m/s in water and 5000 m/s in steel [2].
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Peters, Niamh, Clara Lightner, and John McCaffrey. "An Unusual Case of Gastrointestinal Bleeding in Metastatic Renal Cell Carcinoma." Case Reports in Oncology 13, no. 2 (June 26, 2020): 738–41. http://dx.doi.org/10.1159/000507982.
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Approximately 340 patients are diagnosed with renal cell cancer (RCC) in Ireland each year. Metastatic spread to the lung, lymph nodes and bones is common. Metastatic spread to the gastrointestinal tract, including the small bowel, is a rare phenomenon. Therapeutic advances have led to an improved overall survival in RCC and, as a result, unusual sites of metastatic spread are becoming more common. We present the case of a 68-year-old gentleman presenting with upper gastrointestinal bleeding as a result of metastases to the duodenum from renal cell carcinoma.
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Oxenham, Chantal, Lewis Haddow, Cristian Sandulescu, Angela Bayakwaga, Christopher Sandford, Binta Sultan, Ian Williams, Laura Waters, Simon Edwards, and Shema Tariq. "P076 Five years of feedback for the newly diagnosed course – an evaluation of a peer-led intervention for people diagnosed with HIV." Sexually Transmitted Infections 93, Suppl 1 (June 2017): A41.3—A42. http://dx.doi.org/10.1136/sextrans-2017-053232.121.
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IntroductionNew diagnosis of HIV can be psychologically challenging, and presents an important opportunity to improve health literacy and engagement in care. Peer-led interventions are an effective means of providing support to people living with HIV (PLWH). We present an evaluation of a newly-diagnosed course (NDC) in London.MethodThe NDC, established in its current form in 2011, is accessible to ‘those recently diagnosed or struggling with diagnosis’. Providing a structured, peer-led, group-based, participatory programme delivered by experienced facilitators. NDC comprises 6 sessions (21 contact hours). All participants were invited to complete pre-and post-course questionnaires (using a 4-or 5-point scale), most did at the first and last sessions. This analysis presents data from 2011-2016. Data were analysed in STATA using Wilcoxon signed rank test.ResultsAcross 30 NDCs, 314 participants completed both questionnaires (response rate 87%). The majority were men who have sex with men (91.3%), 72% of whom were of white ethnicity. Approximately 15% were female, the majority Black-African ethnicity (56%) and heterosexual (88%). Heterosexual men and transgender individuals represented 6.5% and 0.3% respectively. The table summarises participant’s responses for selected questions (P Values <0.001 for all comparisons):Pre- and Post-Course Questions:•Pre-course n/N (%)•Post-course n/N (%)*Current emotional state144/136 (43)287/339 (85)*Confidence in dealing with HIV status130/335 (39)307/339 (91)*Confidence around sex and relationships46/336 (14)172/279 (62)*Confidence in the future130/338 (39)290/332 (90)How confident do you feel about disclosing your HIV status?26/338 (8)136/340 (40)How satisfied are you with your ability to get more information about HIV medications?97/336 (29)130/314 (41)How much knowledge do you have about how HIV is transmitted?183/337 (54)324/340 (95)How much do you know about how to access Post Exposure Prophylaxis (PEP)?169/337 (28)274/340 (81)How much knowledge do you have about CD4 count and HIV viral load?82/337 (24)300/340 (88)Personal satisfaction with NDC overall n/N (%) rating ‘mostly’ or ‘fully’ useful324/328 (99)*Questions headed: ‘Thinking about your HIV how would you rate the following’ Respondents rating highest using 4- or 5-point scaleDiscussionThis innovated peer-led NDC engaged over 300 PLWH since 2011, resulting in short-term self-reported improvements. 6-and 12-month questionnaires would assess durability of changes, and we’re exploring the association with attendance at NDC and clinical outcomes (e.g. viral suppression and retention in care). In conclusion, the NDC is a sustainable and acceptable model, providing holistic support and promoting self-management in PLWH.
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Steenbergen, J. M., and H. G. Bohlen. "Sodium hyperosmolarity of intestinal lymph causes arteriolar vasodilation in part mediated by EDRF." American Journal of Physiology-Heart and Circulatory Physiology 265, no. 1 (July 1, 1993): H323—H328. http://dx.doi.org/10.1152/ajpheart.1993.265.1.h323.
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This study evaluated 1) the effect of increased submucosal lymph osmolarity on the regulation of first-order (1A) and second-order (2A) intestinal arterioles and 2) the role of endothelium-derived relaxing factor (EDRF) in hypertonic-induced vasodilation. Increasing the submucosal lymph osmolarity from 280 to 400 mosM, in increments of 30 mosM, resulted in a dose-dependent dilation of 1A and 2A. A submucosal lymph tonicity of 340 mosM, as occurs during glucose and oleic acid absorption, caused dilation of 1A (118%) and 2A (124%) equivalent to that during absorptive hyperemia. The dilation caused by 400 mosM mannitol (137%) was similar to that with 340 mosM NaCl (131%) and approximately 70% of that with 400 mosM NaCl (152%). After EDRF blockade, the responses to sodium hypertonicity decreased by about one-half; blockade reduced mannitol-induced dilation by 22%. These results indicate that sodium hypertonicity, as occurs during absorption, can play a major role in absorptive hyperemia, and about one-half of the dilation is related to a sodium-coupled release of EDRF.
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Grunfeld, A., P. Sinclair, LE Nicolle, and the Canadian Tonsillitis Study Group. "Cefcanel Daloxate versus Penicillin in Acute Streptococcal Pharyngotonsillitis." Canadian Journal of Infectious Diseases 5, no. 3 (1994): 119–24. http://dx.doi.org/10.1155/1994/531572.
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Objective: To determine the efficacy, safety and tolerance of cefcanel daloxate and phenoxymethylpenicillin (PcV) in the treatment of acute pharyngotonsillitis caused by beta-hemolytic streptococci group A (bhsga).Patients and Methods: Randomized, double-blind, multicentre study with subjects randomized 1:1:1:1 to four parallel treatment groups: cefcanel daloxate 150 mg bid, 300 mg bid, 600 mg daily and PcV 300 mg tid. Patients were treated for 10 days with clinical, bacteriological and safety evaluation at inclusion, during therapy (day 5), early after completion of therapy (day 14) and two weeks later (day 28).Results: Of 340 subjects enrolled, 324 were valid for safety analysis and 249 for efficacy analysis. At the short term visit, clinical cure rates for cefcanel daloxate 300 mg bid and PcV groups were similar at approximately 70%. The cure rates for cefcanel daloxate 150 mg bid and 600 mg daily were significantly worse at 57.4 and 54.4%. Approximately 80% of all pretherapy throat swabs grewbhsga. Allbhsgawere susceptible or intermediately susceptible to PcV and cefcanel. The bacterial elimination rate for cefcanel daloxate was 82.8% and for PcV it was 89.8%. The elimination rate was significantly lower in the cefcanel daloxate 150 mg bid and 600 mg daily groups. The clinical cure rates and the bacteriological elimination rates increased by about 10% for cefcanel daloxate 300 mg bid and the PcV groups at the last valid visit and remained significantly better than the other two cefcanel daloxate doses. Adverse events were not significantly different among the four treatment groups.Conclusions: Cefcanel daloxate 300 mg bid was as effective and as well tolerated as PcV 300 mg tid in the treatment of acute pharyngotonsillitis. A lower dose or once-daily dose regimen of cefcanel daloxate was not as effective clinically or bacteriologically.
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Wibowo, Agus, and Bagus Shandy Narmaditya. "Predicting Students' Digital Entrepreneurial Intention: The Mediating Role of Knowledge and Inspiration." Dinamika Pendidikan 17, no. 1 (June 26, 2022): 25–36. http://dx.doi.org/10.15294/dp.v17i1.36161.
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This study was intended to investigate how the direct effect of digital entrepreneurship education on digital entrepreneurship intentions and reveal the mediating role of knowledge and entrepreneurial inspiration. Our quantitative approach uses survey methods to address the proposed hypotheses. Approximately 340 students in five and seventh grade from Universitas Negeri Jakarta were participated as volunteers in this study. Moreover, the collected data were analyzed by using SEM-PLS with SmartPLS 3.0. The findings remarked that digital entrepreneurship education could promote students’ digital entrepreneurship intentions. This study provided insights related to psychological aspects in the form of entrepreneurial inspiration as one of the predictor variables and mediators for increasing digital entrepreneurship intentions. This research also confirmed that entrepreneurial knowledge took a role as a mediator for digital entrepreneurial intentions. This research is the first step to exploring further the critical role of digital entrepreneurship education as the right strategy to enhance the number of new entrepreneurs.
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Bax, J. A., D. J. Roberts, and C. Thomas. "A farm based comparion of grass/white clover with nitrogen based system for dairy cattle." Proceedings of the British Society of Animal Production (1972) 1990 (March 1997): 126. http://dx.doi.org/10.1017/s0308229600019061.
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There is increasing interest in the use of white clover rich swards in dairy cattle systems in response to evironmental pressures and the introduction of milk quotas. White clover (Trifolium repens) in association with Rhizobium bacteria in a mixed sward receiving no fertilizer nitrogen can produce yields equivalent to a grass sward receiving approximately 200 kg N/ha/annum. Field scale cutting experiments (Roberts et al, 1989) have deomstrated that under an intensive 3-cut silage regime a grass/white clover sward receiving no nitrogenous fertilizer can yield 0.71 of the DM herbage output of a grass sward receiving between 320 and 340 kg N/ha/annum. Feeding experiments have demonstrated the ability of white clover to improve milk yield and composition (Castle et al, 1983, Thomson, 1984). To further investigate the potential of white clover for dairy cattle a systems study is being conducted. This paper summarises the performance of the two herds in the first year.
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Hwang, Byungwook, Son Ich Ngo, Young-Il Lim, Myung Won Seo, Sung Jin Park, Ho-Jung Ryu, Hyungseok Nam, and Doyeon Lee. "Reaction Characteristics of Ni-Based Catalyst Supported by Al2O3 in a Fluidized Bed for CO2 Methanation." Catalysts 12, no. 11 (November 2, 2022): 1346. http://dx.doi.org/10.3390/catal12111346.
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CO2 methanation is a promising technology to store renewable energy by converting carbon dioxide with green hydrogen into methane, which is known as power to gas (PtG). In this study, CO2 methanation performance of a Ni/Al2O3 catalyst was investigated in a bubbling fluidized bed (BFB) and the axial gas concentration, temperature, and CO2 conversion were densely analyzed. Moreover, a modified reaction kinetic model was proposed, and the results were compared with experimental data. The bed temperature increased by 11 °C from 340 °C to 351 °C within the first 30 mm of the fluidized bed. The CO2 conversion was approximately 90% within 50 mm from the bottom of the reactor and was maintained above this height. The Ni/Al2O3 catalyst exhibited the highest CO2 conversion (95%) at 320 °C. Using a simple plug-flow reactor model, three optimized kinetic modification factors (1.5094, 0.0238, and 0.2466) were used to fit the experimental data. The hydrodynamic effects significantly influenced the chemical reaction kinetics of the BFB.
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Zou, H., P. H. Ratz, and M. A. Hill. "Role of myosin phosphorylation and [Ca2+]i in myogenic reactivity and arteriolar tone." American Journal of Physiology-Heart and Circulatory Physiology 269, no. 5 (November 1, 1995): H1590—H1596. http://dx.doi.org/10.1152/ajpheart.1995.269.5.h1590.
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The aim of this study was to define the relationship between intraluminal pressure, intracellular calcium concentration ([Ca2+]i), and myosin light-chain (MLC) phosphorylation in isolated arterioles exhibiting myogenic tone. Cremaster muscles were removed from anesthetized rats, and arterioles (approximately 100-microns diam) were dissected from surrounding tissues and cannulated on glass pipettes. Vessels were warmed to 34 degrees C and initially pressurized to 70 mmHg in the absence of intraluminal flow. For [Ca2+]i measurements, vessels were loaded with 5 microM fura 2, and fluorescence emitted by excitation at 340 and 380 nm was measured. Data were considered in terms of changes in the fluorescence ratio (340/380 nm) and collected at steady-state intraluminal pressures between 30 and 170 mmHg. For measurement of MLC phosphorylation, vessels were frozen in acetone-dry ice followed by sonication in homogenizing buffer. Homogenates were separated by two-dimensional gel electrophoresis, and proteins were visualized by silver staining. MLC phosphorylation was quantitated photodensitometrically, and results are expressed as percent total 20-kDa MLC. Increasing intraluminal pressure resultedin significant constriction with increased [Ca2+]i and MLC phosphorylation. For example, the fluorescence ratio was 0.80 +/- 0.04 at 30 mmHg compared with 1.02 +/- 0.05 at 120 mmHg (n = 7 vessels); corresponding MLC-phosphorylation values were 27.7 +/- 1.6 and 39.6 +/- 3.0% (n = 6). MLC phosphorylation in arterioles superfused with 0 mM Ca(2+)-2 mM ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) was 8.5 +/- 0.7%.(ABSTRACT TRUNCATED AT 250 WORDS)
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Ahmad, Sharique, Nirupma Lal, Uroos Fatima, Parul Gupta, and Usman Moosa Hingoora. "Adult duodenojejunal intussusception due to heterotopic pancreas - a rare entity." Bangladesh Journal of Medical Science 13, no. 3 (June 6, 2014): 340–42. http://dx.doi.org/10.3329/bjms.v13i3.12781.
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Approximately 95% of intussusception occurs in children, However it is a rare entity in adults accounting for 0.003% to 0.02 % of all the hospital admissions. Various causes of intussusception are well known, However intussusception caused by heterotropic pancreas is extremely rare and the rarity increases manifolds if it is in the duodenum of an adult and the cause being heterotropic pancreas. We report this rare case of intussusception due to pancreatic heterotropia in 43 year old male who presented with acute pain abdomen. DOI: http://dx.doi.org/10.3329/bjms.v13i3.12781 Bangladesh Journal of Medical Science Vol.13(3) 2014 p.340-342
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Petrov, Roman V., Vladimir M. Petrov, Denis V. Kovalenko, Gennady A. Semenov, and Mirza I. Bichurin. "Magnetic Field Tunable Electromechanical Resonance Properties of Magnetoelectric Bilayer." Solid State Phenomena 233-234 (July 2015): 349–52. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.349.
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The present paper focuses on the magnetoelectric coupling in dimensionally graded ferrite-piezoelectric bilayers in the electromechanical resonance region. Using the bilayer as a transducer which converts the ac magnetic field into an ac electric field shows that the transmission coefficient equals approximately -83 dB for zero bias magnetic field and -44 dB for bias field of 340 Oe. Thus, applying the DC field enables one to obtain the transmission coefficient variation range of 39 dB for the investigated structure. The phenomenon is of importance for the realization of multifunctional magnetoelectric devices including sensors and transducers operating at microwave frequencies.
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Mendes, Pericles M. B., Mário M. Rolim, Renato P. de Lima, Elvira M. R. Pedrosa, Uilka E. Tavares, and Djalma E. Simões Neto. "Estimation of precompression stress in an Ultisol cultivated with sugarcane." Revista Brasileira de Engenharia Agrícola e Ambiental 23, no. 5 (May 2019): 336–40. http://dx.doi.org/10.1590/1807-1929/agriambi.v23n5p336-340.
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ABSTRACT Compressive soil properties are typically used for the understanding of compaction process. As an alternative to laboratory tests, pedo-transfer functions have been used to estimate the mechanical behaviour of soil as a function of soil physical parameters. The impact of soil bulk density (BD) and gravimetric water content (w) was examined on soil strength and pedo-transfer functions were proposed to predict the precompression stress (σp) in an Ultisol cultivated with sugarcane. Undisturbed soil cores were sampled at the depths of 0-0.20 and 0.20-0.40 m, subjected to different water contents, and subsequently, compression tests were performed to determine σp. The data were subjected to analysis of variance and regression analysis. Bulk density and w affected σp positively and negatively, respectively. Approximately 70% of the variation of the σp could be explained as a function of BD and w through an accessible multiple regression model. Comparisons with other pedo-transfer functions showed that estimates of σp may be rather sensitive to soil management and textural classes. Variations imposed by soil management and cohesive character into depth suggest that independent models should be considered to characterise compressive behaviour of soil by horizon or layer.
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Wang, Shichao, Gaoqun Qiao, Xiaoyan Chen, Xinzhen Wang, and Hongzhi Cui. "Synthesis of ZnO Hollow Microspheres and Analysis of Their Gas Sensing Properties for n-Butanol." Crystals 10, no. 11 (November 6, 2020): 1010. http://dx.doi.org/10.3390/cryst10111010.
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ZnO hollow microspheres with a diameter of approximately 1.4 μm were successfully synthesized by a facile one-step chemical precipitation method using trisodium citrate dihydrate as a morphology control agent. The ZnO hollow microspheres consisted of nanoplates and had good dispersibility. Control experiments revealed that trisodium citrate dihydrate played an important role in regulating the morphologies of ZnO products. The morphology of the ZnO product evolved from nanowires to hollow microspheres with the addition of trisodium citrate dihydrate. The sensor response of ZnO hollow microspheres toward 100 ppm n-butanol reached 86.6 at the optimum operating temperature of 340 °C, which was approximately three times higher than that of ZnO nanowires. In addition, the ZnO hollow microspheres also displayed good selectivity and long-term work stability toward n-butanol. The excellent gas sensing performance of ZnO hollow microspheres may be ascribed to the unique hollow sphere structure with high exposed polar crystal surface.
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Santiago-Cortés, M., Y. D. Mayya, and D. Rosa-González. "Study of the young and old compact stellar cluster population in M81." Proceedings of the International Astronomical Union 5, S266 (August 2009): 532. http://dx.doi.org/10.1017/s1743921309991955.
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AbstractWe study the population of compact stellar clusters in M 81 using the HST/ACS images in the filters F435W, F606W and F814W that cover a total field of view of approximately 340 square arcmin, the largest area covered to date for this galaxy. We present details about the selection criteria, which were based on both morphological and photometrical features. The extracted sample of compact stellar clusters shows the presence of two cluster populations, a blue cluster group (young) with more than 300 objects, and a red cluster group (old) containing 138 objects. Surprisingly, the young group lacks clusters more massive than 10 000 M⊙ which are present in large numbers in its neighbor M 82. The luminosity function of the young group follows a power-law distribution with an index of 2.0. The luminosity function of the red group closely resembles that of the globular clusters in the Milky Way. Assuming an age of 5 Gyr, these red clusters have masses between 0.1 and 10 × 106 M⊙.
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Jung, Woojong. "Analysis of the Economic and Environmental Effects by the Offshore Wind Power Construction: In case of Kitakyushu City, Japan." Business and Management Studies 1, no. 2 (August 18, 2015): 159. http://dx.doi.org/10.11114/bms.v1i2.1008.
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The purpose of this study is to analyze the economic spillover effects and environmental impact of building offshore wind turbines on a local economy in Japan. Japan is facing a great turning point in its energy policy in the wake of the Great East Japan Earthquake, further increasing the importance of renewable energy. The offshore wind turbines experiment in Kitakyushu City is anticipated to showcase the potential of offshore wind power in Japan for the future and dynamize the local economy. As such, in this study, an economic and environmental impact assessment by Input–Output (I-O) analysis was conducted for the construction of the offshore wind turbines. The results show that building one hundred 3MW offshore wind turbine units will increase the induced production value by approximately 205.2 billion yen, equivalent to roughly 2.7% of Kitakyushu City’s total production value. Additionally, it is anticipated to create approximately 14 500 jobs. In terms of environmental impact, the increase in production is estimated to increase CO2 emissions by nearly 340 000 tonnes (an increase of approximately 2.1%). Accordingly, the environmental impact of building offshore wind turbines in Kitakyushu City is smaller than the economic impact, meaning that a sustainable between the economy and the environment can be found by the diffusion of renewable energy.
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Tan, Yun, Wei Li, Weiwei Hu, Xiaofang Shi, and Liang Tian. "The Effect of ECAP Temperature on the Microstructure and Properties of a Rolled Rare Earth Magnesium Alloy." Materials 12, no. 9 (May 12, 2019): 1554. http://dx.doi.org/10.3390/ma12091554.
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Deformation of an as-rolled rare earth Mg-2Y-0.6Nd-0.6Zr alloy, at different temperatures, was carried out along the BC (90° anticlockwise rotation of the samples after each ECAP pass) route by equal channel angular pressing (ECAP). The effects of the deformation temperature and the predeformation on the microstructure of the magnesium alloy were determined by the microstructure examination. The slip systems and texture change of the Mg-2Y-0.6Nd-0.6Zr alloy were investigated by X-ray diffraction (XRD) and electron backscattered diffraction (EBSD), after equal channel angular deformation. The results showed that after seven passes of rolling, the grain size in the Mg-2Y-0.6Nd-0.6Zr alloy was refined to approximately 22 µm and the slip occurred mainly by a cylindrical slip and a pyramidal slip. After one pass of ECAP at 340 °C, the internal average grain size was significantly reduced to 11 µm, the cylindrical diffraction intensity clearly weakened, and the pyramidal diffraction intensity increased. EBSD pole figure analysis revealed that the base texture of the rolled Mg-2Y-0.6Nd-0.6Zr alloy weakened from 24.31 to 11.34 after ECAP. The mechanical properties indicated that the tensile strength and elongation of the rolled Mg-2Y-0.6Nd-0.6Zr alloy reached maximum values, when the deformation temperature was 340 °C.
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Yang, Zhenghao, Yang Du, Qi Geng, Xu Gao, Haonan Er, Yuanfei Liu, and Guangyu He. "Performance Analysis of a Hydrogen-Doped High-Efficiency Hybrid Cycle Rotary Engine in High-Altitude Environments Based on a Single-Zone Model." Energies 15, no. 21 (October 26, 2022): 7948. http://dx.doi.org/10.3390/en15217948.
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The power attenuation of internal combustion engines in high-altitude environments restricts the performance of unmanned aerial vehicles. Herein, a single-zone model of a hydrogen-doped high-efficiency hybrid cycle rotary engine that considers high-altitude environments was proposed. The indicated values for power, thermal efficiency, and specific fuel cost were used to evaluate the power performance, energy conversion efficiency, and economic performance of the engine, respectively. Then, the effects of adjusting the hydrogen fraction, ignition angle, and rotational speed on high-altitude performance were analyzed. The results showed that high-altitude environments prolonged combustion duration and reduced in-cylinder pressure, thereby causing power attenuation; however, increasing the hydrogen fraction can increase the indicated power. At an altitude of 6 km, the indicated power with a hydrogen fraction of 0.3 was approximately 20.7% higher than that obtained with pure gasoline. The ignition angle and hydrogen fraction corresponding to the optimal indicated thermal efficiency increased with increasing altitude. At an altitude of 6 km, the indicated thermal efficiency reached its maximum (36.4%) at an ignition angle of 340 [CA°] and a hydrogen fraction of 0.15. At high altitudes, rotational speeds below 6000 rpm and ignition angles of 340–345 [CA°] were beneficial in reducing indicated specific fuel costs.
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Radnai, T., and H. Ohtaki. "Intramolecular and Liquid Structures of Tetramethylurea Studied by Means of X-Ray Diffraction." Zeitschrift für Naturforschung A 47, no. 9 (September 1, 1992): 1003–10. http://dx.doi.org/10.1515/zna-1992-0912.
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Abstract The intramolecular and liquid structures of tetramethylurea (TMU) were investigated by the liquid x-ray diffraction method. It is confirmed that in the liquid state the four methyl groups are out of the plane which is constructed by the O, C, and the two N atoms, the molecular structure being similar to what had been found in the gas phase. All structural parameters are in good agreement with those of TMU determined in the gas phase and with those of amide derivatives in the liquid phase. The liquid is characterized by a random distribution of molecules as predominant, but a weak molecular ordering characterized by approximately two intermolecular nonbonding Me ··· O distances at 340 pm is proposed
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Huang, Kun Lan, Yi Yang, and Yi Qin. "Sintering Kinetics of the Powder during Fields-Activated Micro-Forming and Sintering (Micro-FAST) of Copper Micro-Gears." Key Engineering Materials 622-623 (September 2014): 854–60. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.854.
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Forming of micro-components from powder with fields-activated sintering technology (FAST) renders different forming and sintering mechanisms, comparing to that occurring during the forming of macro-sized components with a similar technology. Establishing a good understanding of these mechanisms would help process design and control aiming at achieving desired quality of the components to be formed. This paper presents a study and the results on the sintering kinetics of the powder during Micro-FAST for the fabrication of micro-gears (the module is 0.2 and the pitch diameter 1.6 mm) from copper powder. The results showed that the densification of copper powder is related largely to the bulk plastic-deformations of the particles and the melting of the particles at contact interfaces. Particularly, it is revealed that plastic deformations of the copper particles mainly occurred at approximately 340 °C and melting of the particle-interfaces at approximately 640 °C. Differently, in a densification process with a traditional powder sintering method, grain growth and neck growth would, normally, be two dominant mechanisms that achieve the densification of powder.
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Segawa, Takahiro, Takahiro Yonezawa, Hiroshi Mori, Ayumi Akiyoshi, Morten E. Allentoft, Ayako Kohno, Fuyuki Tokanai, Eske Willerslev, Naoki Kohno, and Hidenori Nishihara. "Ancient DNA reveals multiple origins and migration waves of extinct Japanese brown bear lineages." Royal Society Open Science 8, no. 8 (August 2021): 210518. http://dx.doi.org/10.1098/rsos.210518.
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Little is known about how mammalian biogeography on islands was affected by sea-level fluctuations. In the Japanese Archipelago, brown bears ( Ursus arctos ) currently inhabit only Hokkaido, the northern island, but Pleistocene fossils indicate a past distribution throughout Honshu, Japan's largest island. However, the difficulty of recovering ancient DNA from fossils in temperate East Asia has limited our understanding of their evolutionary history. Here, we analysed mitochondrial DNA from a 32 500-year-old brown bear fossil from Honshu. Our results show that this individual belonged to a previously unknown lineage that split approximately 160 Ka from its sister lineage, the southern Hokkaido clade. This divergence time and fossil record suggest that brown bears migrated from the Eurasian continent to Honshu at least twice; the first population was an early-diverging lineage (greater than 340 Ka), and the second migrated via Hokkaido after approximately 160 Ka, during the ice age. Thus, glacial-age sea-level falls might have facilitated migrations of large mammals more frequently than previously thought, which may have had a substantial impact on ecosystem dynamics in these isolated islands.
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Noble, CL. "Germination and growth of Secale montanum Guss. in the presence of sodium chloride." Australian Journal of Agricultural Research 36, no. 3 (1985): 385. http://dx.doi.org/10.1071/ar9850385.
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The salt tolerance of Secale montanum varied at different growth stages. Tolerance during germination was high, with NaCl of more than 340 mol m-3 necessary to reduce germination by 50%. Seedling emergence was more sensitive to NaCl with a 50% reduction occurring at approximately 300 mol m-3. Up to 200 mol m-3aC1, all emerged seedlings reached the first leaf stage, although shoot dry weight of emerged seedlings at 200 mol m-3 NaCl was reduced to 64% of that of seedlings under non-saline conditions. During later plant growth, shoot growth (dry weight) had a salt tolerance threshold of 20 mol m-3 NaCl (electrical conductivity, ECw, of 2.7 mS cm-1). Subsequent yield decline up to approximately 100 mol m-3 NaCl (ECw, = 10.8 mS cm-1) was 6.7% of non-saline yield per mS cm-1 increase in ECw. At higher NaCl concentrations a more reciprocal form of yield decline occurred. Considerable plantto- plant variation for shoot dry weight existed in the presence of NaCl, indicating scope for selection to increase the tolerance of S. montanum. Osmotic adjustment was aided by a reduction in tissue water content under increasing NaCl and by the accumulation of sodium and chloride. Sodium was mainly accumulated in the roots, although the roots increased their selectivity for potassium over sodium. Chloride was mainly accumulated in the shoots. S. montanum could be classed as moderately salt tolerant, a tolerance similar to such pasture grasses as Lolium perenne, Phalaris aquatica and Festuca arundinacea.
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Sack, Patrick J., Ron F. Berry, J. Bruce Gemmell, Sebastien Meffre, and Andrew West. "U–Pb zircon geochronology from the Alexander terrane, southeast Alaska: implications for the Greens Creek massive sulphide deposit." Canadian Journal of Earth Sciences 53, no. 12 (December 2016): 1458–75. http://dx.doi.org/10.1139/cjes-2016-0032.
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This paper presents results of a laser ablation – inductively coupled plasma – quadrapole mass spectrometer (LA–ICP–QMS) U–Pb dating study of small in situ zircon grains from samples collected in the vicinity of the Greens Creek massive sulphide deposit, on northern Admiralty Island, southeast Alaska. The Greens Creek mine is a volcanogenic massive sulphide deposit in the central portion of the Alexander Triassic metallogenic belt (ATMB) and is one of the top global silver producers despite having a dominantly mafic metavolcanic stratigraphic footwall. The stratigraphic footwall is a Mississippian mafic metavolcanic sequence with a protolith age of approximately 340–330 Ma. The first U–Pb zircon constrained chronostratigraphy for the area places the deposit near, or at, the base of the host Late Triassic stratigraphy just above an approximately 100 million year old unconformity and probably 10–15 million years older than mineralization at the Palmer and Windy Craggy deposits in the northern portion of the ATMB. The stratigraphic location of the Greens Creek deposit is atypical for a syngenetic massive sulphide deposit, and this may, at least partly, explain its unusual metal endowment. Pre-mineralization Permian U–Pb zircon metamorphic ages are consistent with published 273–260 Ma white mica ages related to the collision of the Admiralty and Craig subterranes, the basement to the ATMB. The much older age of the footwall rocks and their Permian pre-mineralization metamorphism demonstrates that though the mafic volcanic rocks are not genetically linked to the deposit, they likely influenced the style of alteration and mineralization.
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Lempke, Landon B., Julianne D. Schmidt, and Robert C. Lynall. "Concussion Knowledge and Clinical Experience Among Athletic Trainers: Implications for Concussion Health Care Practices." Journal of Athletic Training 55, no. 7 (June 18, 2020): 666–72. http://dx.doi.org/10.4085/1062-6050-340-19.
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Context Athletic trainers (ATs) are heavily involved in concussion assessment and return-to-play (RTP) decision making. Despite ATs' crucial role, few researchers have directly examined ATs' knowledge of concussions or whether concussion knowledge or clinical experience affects clinical concussion-management practices. Objective To determine the overall concussion knowledge of ATs and whether concussion knowledge and clinical experience affect concussion-assessment and -management practices. Design Cross-sectional study. Setting Online survey. Patients or Other Participants Random convenience sample of 8725 (15.0% response rate [1307/8725]; certified, 14.8 ± 10.6 years) ATs surveyed from the National Athletic Trainers' Association membership. Main Outcome Measure(s) The survey collected demographics, concussion-assessment and -management tools used, and concussion knowledge (patient-clinician scenarios, signs and symptoms recognition). We used multiple logistic regression models to determine the odds ratios (ORs) for using assessment and management tools based on signs and symptoms recognition and years of clinical experience. Results The ATs correctly identified 78.0% ± 15.1% of concussion signs and symptoms. Approximately 46% (357/770) of ATs indicated an athlete could RTP if the athlete stated he or she had a “bell rung.” Every additional year of clinical experience decreased the odds of using standardized sideline-assessment tools by 3% (OR = 0.97, 95% Confidence Interval [CI] = 0.95, 0.99). The odds of using standardized sideline tools (OR = 0.98, 95% CI = 0.96, 0.99) and symptom checklists (OR = 0.98, 95% CI = 0.97, 0.99) for RTP assessment were significantly decreased for each additional year of clinical experience. No other tools used for RTP assessment were influenced by signs and symptoms recognition (P ≥ .136) or clinical experience (P ≥ .158). Conclusions The ATs with greater clinical experience had lower odds of using concussion-assessment and -management tools. Athletic trainers should frequently review and implement current consensus guidelines into clinical practice to improve concussion recognition and prevent improper management.
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Haman, D. Z., T. H. Yeager, R. C. Beeson, and G. W. Knox. "Multiple Pot Box for Container Plant Production." Journal of Environmental Horticulture 16, no. 1 (March 1, 1998): 60–63. http://dx.doi.org/10.24266/0738-2898-16.1.60.
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Abstract Viburnum odoratissimum (Ker-Gawl.) plants were grown for 15 weeks in 3-liter (#1) containers in black multipot boxes that contained a water reservoir and in a conventionally spaced system on black polypropylene. Irrigation events were based on plants in multipot boxes which resulted in under-watering of plants in conventionally spaced containers. Plants grown in the multipot box production system had higher shoot and root dry weights as compared to plants grown in conventionally spaced containers, and their growth indices of the plants in multipot boxes increased at a greater rate than that of plants from the conventional system. Approximately 210 mm (8.3 in) of overhead irrigation was applied during the experiment, in addition to 340 mm (13.3 in) of rain.
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Kaawash, N. M. S., D. I. Halge, V. N. Narwade, J. W. Dadge, and K. A. Bogle. "Fabrication of Near Ultraviolet Photodetector using α-Fe2O3 Thin FilmSynthesized via Spray Coating Technique." Journal of Physics: Conference Series 2426, no. 1 (February 1, 2023): 012011. http://dx.doi.org/10.1088/1742-6596/2426/1/012011.
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Abstract A UV photodetector was created using a spray-deposited α-Fe2O3 thin film on a glass substrate at 160 °C. The film’s thickness was approximately 110 nm. With a near UV light at a wavelength of 340 nm and an intensity of 140 µW/cm2, the photosensitivity of an individual α-Fe2O3 thin film photodetector was greater than 40%. An individual α-Fe2O3 thin film-based photodetector’s rapid photoresponse time of 1.6 ms and responsivity of ~ 1 mA/W can be attributed to the band gap and chemisorption of oxygen on the film’s surface. The photodetectors’ simple, low-cost, and large-scale fabrication demonstrates the fabrication of a stable, reversible, and rapid photo-responsive photodetector for near UV wavelength.
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Król, Mariusz, Przemysław Snopiński, Jiří Hajnyš, Marek Pagáč, and Dariusz Łukowiec. "Selective Laser Melting of 18NI-300 Maraging Steel." Materials 13, no. 19 (September 25, 2020): 4268. http://dx.doi.org/10.3390/ma13194268.
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In the present study, 18% Ni 300 maraging steel powder was processed using a selective laser melting (SLM) technique to study porosity variations, microstructure, and hardness using various process conditions, while maintaining a constant level of energy density. Nowadays, there is wide range of utilization of metal technologies and its products can obtain high relative density. A dilatometry study revealed that, through heating cycles, two solid-state effects took place, i.e., precipitation of intermetallic compounds and the reversion of martensite to austenite. During the cooling process, one reaction took place (i.e., martensitic transformation), which was confirmed by microstructure observation. The improvements in the Rockwell hardness of the analyzed material from 42 ± 2 to 52 ± 0.5 HRC was improved as a result of aging treatment at 480 °C for 5 h. The results revealed that the relative density increased using laser speed (340 mm/s), layer thickness (30 µm), and hatch distance (120 µm). Relative density was found approximately 99.3%. Knowledge about the influence of individual parameters in the SLM process on porosity will enable potential manufacturers to produce high quality components with desired properties.
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Berry, Leslie R., Frank V. Puzzuoli, and Mark W. C. Hatton. "On the interaction between 5-hydroxytryptamine and N-acetylneuraminic acid under aqueous conditions." Canadian Journal of Biochemistry and Cell Biology 63, no. 7 (July 1, 1985): 757–63. http://dx.doi.org/10.1139/o85-095.
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A complex designated 5-HT–NeuAc was formed between 5-hydroxytryptamine (5-HT) and N-acetylneuraminic acid (NeuAc) under aqueous conditions. Complex formation was encouraged by exposure to light (3000–3800 Å; 1 Å = 0.1 nm) and freeze-drying and the freeze-dried complex was isolated by gel filtration chromatography. Although stable to rechromatography on Bio-Gel P-2 if H2O was the eluent, 5-HT–NeuAc dissociated into the free components when placed in 0.1 M NaCl. Chemical analyses of the isolated complex showed that an equimolar amount of 5-HT and NeuAc was present and that all group functions were intact; these data suggested that the association between 5-HT and NeuAc was noncovalent. Spectrophotometric measurements demonstrated a small increase (approximately 12%) in extinction coefficient (275 nm) and a large increase (340- to 440-fold) in fluorescence emission (340 nm) compared with 5-HT alone. Data obtained from 1H nuclear magnetic resonance spectroscopy (250 MHz) of 5-HT and NeuAc standards compared closely to published reports. In comparison, measurements made with 5-HT-NeuAc showed that all 5-HT protons were slightly deshielded; of the NeuAc protons, slight deshielding of H8 and significant shielding of H3eq, H3ax, and H6 was observed. From these observations, a model describing the association between 5-HT and NeuAc is proposed.
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Ravandi, Farhad, Jorgensen L. Jeffrey, Deborah A. Thomas, Susan O'Brien, Elias Jabbour, Gautam Borthakur, Rebecca Garris, et al. "Minimal Residual Disease (MRD) Assessed By Multi-Parameter Flow Cytometry (MFC) Is Highly Predictive of Outcome in Adult Patients with Acute Lymphoblastic Leukemia (ALL)." Blood 124, no. 21 (December 6, 2014): 1079. http://dx.doi.org/10.1182/blood.v124.21.1079.1079.
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Abstract Purpose - Predicting outcome in patients with ALL has been traditionally based on pre-treatment characteristics such as age, white blood cell count (WBC) and cytogenetics. Minimal residual disease is a surrogate to the complex interaction of disease biology and therapy and its role in assigning risk is well-established. Many prior studies in patients with ALL have used molecular markers of MRD with few studies evaluating the role of multi-parameter flow cytometry (MFC) in the adult population. We investigated the predictive value of MRD assessed by MFC among 340 patients with ALL treated between March 2004 and March 2014 using regimens including the hyperCVAD backbone. Methods - Among 340 patients with B-ALL treated in this period 323 (95%) achieved complete remission (CR) or CR without platelet recovery (CRp) and were included in this study. Median age was 52 (Range, 15-84). Median WBC was 9.35 x109/L (Range, 0.4-658.1 x109/L). Cytogenetics were normal in 62 (18%), Philadelphia+ in 146 (43%), 11q23/rearranged MLL in 14 (4%), aneuploid in 45 (13%), hyperdiploid in 29 (9%), hypodiploid in 13 (4%), insufficient metaphases/ not done in 31 (9%). MRD by MFC was assessed with a sensitivity of 0.01%, using a 15-marker, 4-color panel in the first half of the study and subsequently a 6-color panel. Bone marrow specimens for MRD assessment were obtained at the time of achievement of CR and at approximately 3 month intervals thereafter. Results - 260 patients had available samples at CR and 166 (64%) became MRD negative. Achieving MRD negative status at CR was associated with a statistically significant improvement in disease-free survival (P =0.004) and overall survival (P=0.03). 215 patients were evaluated for MRD at approximately 3 months and 201 (93%) became negative. Achieving MRD negative status at approximately 3 months was also associated with a statistically significant improvement in DFS (P=0.002) and OS (P=0.003). 166 patients were evaluated for MRD at approximately 6 months and 160 (96%) became negative. Achieving MRD negative status at approximately 6 months was also associated with a statistically significant improvement in DFS (P<0.0001) and OS (P<0.0001). Figure below demonstrates the DFS and OS by MRD status at CR (Figure 1a and 1b), at 3 months (Figure 2a and 2b), and at 6 months (Figure 3a and 3b) with patients censored at the time of undergoing an allogeneic stem cell transplant or last follow-up. On multivariate analysis including age, WBC at presentation, cytogenetics (standard vs. high risk), and MRD status at CR, 3 months and 6 months, achieving an MRD negative status at CR was an independent predictor of DFS (P<0.05). Conclusion – Achievement of an MRD negative state assessed by MFC is an important predictor of DFS and OS in patients with ALL Figure 1 Figure 1. Figure 2 Figure 2. Figure 3 Figure 3. Disclosures No relevant conflicts of interest to declare.
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Sada, K., M. Shirai, and I. Ninomiya. "X-ray TV system for measuring microcirculation in small pulmonary vessels." Journal of Applied Physiology 59, no. 3 (September 1, 1985): 1013–18. http://dx.doi.org/10.1152/jappl.1985.59.3.1013.
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We developed a new system that consists of 1) a specially designed X-ray apparatus, 2) an X-ray-sensitive 1-in. Vidicon camera, and 3) a digital image-processing device. The picture element is approximately 20 micron in size, and the time required for one frame is 1/30 s. Using this system, we measured the internal diameter (ID), the cross-sectional area, flow velocity, volume flow, and transit time of small pulmonary vessels of approximately 100–500 micron at control and with serotonin in anesthetized cats. Flow velocity and volume flow from large [458 +/- 22 (SE) micron] to small (340 +/- 32 micron) arteries were 5.4 +/- 0.4 cm/s and 0.53 +/- 0.06 ml/min, respectively. Transit times of the contrast medium from large to small arteries (Ta) and to large veins (Tv) were 0.68 +/- 0.04 and 3.71 +/- 0.25 s, respectively. Serotonin injection (20–30 micrograms/kg iv) decreased ID, flow velocity, and volume flow of arteries by 8–48, 32, and 76%, respectively, whereas Ta and Tv increased by 91 and 69%, respectively. The system can provide useful information regarding the local circulation in the lung.