42,977 research outputs found
Experimental study on heat transfer of the magnetorheological fluids
No full textThermal conductivity of magnetorheological suspensions synthesized with iron powder and silicone oil is experimentally investigated for varying particle volume fractions (5, 20, and 40 vol%) of two different grades of iron (Fe) and magnetic field strengths. In order to determine the temperature range at which the thermal conductivity of MR fluids is more effective for different heat transfer applications, the experiments are done for three different temperature intervals in three different temperature ranges: from -20 to 0 degrees C, from 0 to 50 degrees C, and from 50 to 100 degrees C. In this study, ISO 8301 'Thermal insulation-determination of steady state thermal resistance and related properties-heat flow meter apparatus' is used. The thermal conductivity of the MR fluids shows an increase with increasing magnetic field and volume fraction in the temperature intervals from 0 to 50 degrees C and from 50 to 100 degrees C. In particular, there is a substantial enhancement in the thermal conductivity for the 50-100 degrees C temperature interval (enhancement ratio by almost 134% for 40SM at H = 150 G). However, the thermal conductivity shows a decrease in the lower temperature interval from 20 to 0 degrees C (a decrease by 42% for 40SM at 150 G), which could be due the effect of the thermal conductivity of silicone oil at lower temperatures. Although the heat transfer coefficient is higher for higher particle concentrations, the percentage increase is more pronounced for lower particle concentrations, especially in the 0 to 50 degrees C temperature interval (for the 40SM sample at 150 G 18% an enhancement for a 20 K temperature difference is observed, whereas for the 20% MR fluid sample, the enhancement is 34%)
Evolution of the G+C content frontier in the rat cytomegalovirus genome
No full textWithin the 230138 bp of the rat cytomegalovirus (RCMV) genome, the G+C content changes abruptly at position 142644, constituting a G+C content frontier. To the left of this point, overall G+C content is 69.2%, and to the right it is only 47.6%. A region of extremely low G+C content (33.8%) is found in the 5 kb immediately to the right of the frontier, in which there are no predicted coding sequences. To the right of position 147501, the G+C content rises and predicted coding sequences reappear. However, these genes are much shorter (average 848bp, 50% G+C) than those in the left two-thirds of the genome (average 1462bp, 70% G+C). Whole genome alignment of several viruses indicates that the initial ultra-low G+C region appeared in the common ancestor of the genera Cytomegalovirus and Muromegalovirus, and that the lowering of G+C in the right third has been a subsequent process in the lineage leading to RCMV. The left two-thirds of RCMV has stop codon occurrences at 67.5% of their expected level, based on a modified Markov chain model of stop codon distribution, and the corresponding figure for the right third is 78%. Therefore, despite heavy mutation pressure, selective constraint has operated in the right third of the RCMV genome to maintain a degree of gene length unusual for such low G+C sequences
1-{2-Benzyloxy-2-[4-(morpholin-4-yl)phenyl]ethyl}-1H-benzimidazole
No full textIn the title compound, C26H27N3O2, the morpholine ring adopts a chair conformation. The benzene and phenyl rings are inclined to the benzimidazole mean plane by 7.28 (6) and 61.45 (4)°, respectively. In the crystal, pairs of weak C—H...O hydrogen bonds link the molecules into inversion dimers. These dimers are further connected via weak C—H...N hydrogen bonds. A weak C—H...π interaction is also observed
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
FIGURE 4 in Knautia goecmenii (Caprifoliaceae): an unexpected caespitose suffrutescent new species from the Western Anatolia, Turkey
No full textFIGURE 4. SEM photographs of Knautia goecmenii: A−C. Pollen grain and detail of surface; D−F. fruit with involucel and involucel surface detail; G. Peduncle surface detail.Published as part of Yildirim, Hasan, Özdöl, Tuğkan, Can, Ilgin Deniz, Erdem, Seval, Oğur, Erdinç & Özüdoğru, Bariş, 2022, Knautia goecmenii (Caprifoliaceae): an unexpected caespitose suffrutescent new species from the Western Anatolia, Turkey, pp. 97-110 in Phytotaxa 531 (2) on page 103, DOI: 10.11646/phytotaxa.531.2.2, http://zenodo.org/record/586909
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
No full textThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Efficient removal of methyl orange from aqueous solutions using ulexite
No full textUlexite, a natural boron mineral was used as an adsorbent for methyl orange (MetO) removal from aqueous solutions. SEM/EDS, IEP, BET, XPS and FTIR analyses were used for the characterization of ulexite. The adsorption characteristics of MetO by ulexite were investigated using batch adsorption experiments with varying contact time, pH, initial dye concentration and temperature. Batch adsorption experiments showed that the equilibrium time was 90 min and the reaction kinetics followed pseudo-first-order model. Equilibrium adsorption data were best fitted by the Liu isotherm and the maximum amount of MetO adsorbed per unit weight of ulexite was 1477.6 mg/g (experimental) at 298 K. The equilibrium experiments were repeated for different temperatures (288, 298 and 308 K) and the obtained data were used to calculate the thermodynamic parameters. Based on the results, the adsorption process was exothermic, spontaneous and thermodynamically favourable under the experimental conditions. The adsorption mechanism was elucidated by SEM/EDS, BET, XPS and FTIR analyses of ulexite before and after MetO adsorption. These results suggested that adsorption mechanism includes pi-p bonding, electrostatic attraction, hydrogen bonding and OH-pi bonding. The reuse experiments demonstrated a 14.17 % reduction in the adsorbed amount of MetO per unit weight of ulexite, after the fifth adsorption-desorption cycle. The obtained results indicate that ulexite is potentially an efficient adsorbent for MetO, especially for high initial concentrations. (c) 2021 Elsevier B.V. All rights reserved
Acute Ethanol Administration Rapidly Increases Phosphorylation of Conventional Protein Kinase C in Specific Mammalian Brain Regions in Vivo
No full textBackground
Protein kinase C (PKC) is a family of isoenzymes that regulate a variety of functions in the central nervous system including neurotransmitter release, ion channel activity, and cell differentiation. Growing evidence suggests that specific isoforms of PKC influence a variety of behavioral, biochemical, and physiological effects of ethanol in mammals. The purpose of this study was to determine whether acute ethanol exposure alters phosphorylation of conventional PKC isoforms at a threonine 674 (p-cPKC) site in the hydrophobic domain of the kinase, which is required for its catalytic activity.
Methods
Male rats were administered a dose range of ethanol (0, 0.5, 1, or 2 g/kg, intragastric) and brain tissue was removed 10 minutes later for evaluation of changes in p-cPKC expression using immunohistochemistry and Western blot methods.
Results
Immunohistochemical data show that the highest dose of ethanol (2 g/kg) rapidly increases p-cPKC immunoreactivity specifically in the nucleus accumbens (core and shell), lateral septum, and hippocampus (CA3 and dentate gyrus). Western blot analysis further showed that ethanol (2 g/kg) increased p-cPKC expression in the P2 membrane fraction of tissue from the nucleus accumbens and hippocampus. Although p-cPKC was expressed in numerous other brain regions, including the caudate nucleus, amygdala, and cortex, no changes were observed in response to acute ethanol. Total PKC? immunoreactivity was surveyed throughout the brain and showed no change following acute ethanol injection
Author Correction: A corridor of exposed ice-rich bedrock across Titan’s tropical region (Nature Astronomy, (2019), 3, 7, (642-648), 10.1038/s41550-019-0756-5)
No full textIn the version of this Article originally published, the author Rosaly Lopes was mistakenly affiliated with Northern Arizona University. Her affiliation has now been corrected to: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA. © 2019, Springer Nature Limited
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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