1,496 research outputs found
Tumor suppressor genes and their underlying interactions in paclitaxel resistance in cancer therapy
Reproductive traits and mandibular gland pheromone of anarchistic honey bee workers Apis mellifera occurring in China
International audienceAbstractIn honey bee colonies, workers, in particular of “anarchistic” lineages, can activate their ovaries and lay eggs, even in the presence of the queen. We identified three queenright colonies showing typical signs of worker reproduction. To characterize this new lineage, we extracted the mandibular gland and analyzed it using gas chromatography. The total amounts of the five main components of the mandibular gland, namely methyl p-hydroxyben-zoate (HOB), 9-oxo-2(E)-decenoic acid (9-ODA), (S)-9-hydroxy-(E)-2-decenoic acid (9-HDA), 10-HDA, and 10-hydroxyde-canoic acid (10-HDAA) were significantly higher in the mandibular gland profiles of workers with activated ovaries (AWs, 8.88 ± 1.71 μg) compared to workers with inactivated ovaries (IAWs, 4.00 ± 2.09 μg). Furthermore, the chemical profiles of IAWs were dominated by the “worker substances” 10-HDA (34.64 ± 8.19 %) and its precursor 10-HDAA (22.88 ± 4.95 %), while the chemical profiles in AWs were dominated by the precursor of the queen substance 9-HDA (40.04 ± 7.55 %). The ratios of two precursor substances 10-HDAA/9-HDA of IAWs were more worker like (>1.0) whereas AWs were more queen like (≤1.0). These results suggest that the mandibular pheromones of anarchistic workers resemble a more queen-like reproductive active profile and that these workers may represent a reversion to a more basal reproductive phenotype
Copper-based charge transfer multiferroics with a configuration
Multiferroics are materials with a coexistence of magnetic and ferroelectric
order allowing the manipulation of magnetism by applications of an electric
field through magnetoelectric coupling effects. Here we propose an idea to
design a class of multiferroics with a configuration using the magnetic
order in copper-oxygen layers appearing in copper oxide high-temperature
superconductors by inducing ferroelectricity. Copper-based charge transfer
multiferroics SnCuO2 and PbCuO2 having the inversion symmetry breaking
polar space group are predicted to be such materials. The active inner s
electrons in Sn and Pb hybridize with O states leading the buckling in
copper-oxygen layers and thus induces ferroelectricity, which is known as the
lone pair mechanism. As a result of the configuration, SnCuO2 and PbCuO2
are charge transfer insulators with the antiferromagnetic ground state of the
moment on Cu retaining some strongly correlated physical properties of parent
compounds of copper oxide high-temperature superconductors. Our work reveals
the possibility of designing multiferroics based on copper oxide
high-temperature superconductors.Comment: 18 pages, 5 figures, 1 tabl
Elemental topological ferroelectrics and polar metals of few-layer materials
Ferroelectricity can exist in elemental phases as a result of charge
transfers between atoms occupying inequivalent Wyckoff positions. We
investigate the emergence of ferroelectricity in two-dimensional elemental
materials with buckled honeycomb lattices. Various multi-bilayer structures
hosting ferroelectricity are designed by stacking-engineering. Ferroelectric
materials candidates formed by group IV and V elements are predicted
theoretically. Ultrathin Bi films show layer-stacking-dependent physical
properties of ferroelectricity, topology, and metallicity. The two-bilayer Bi
film with a polar stacking sequence is found to be an elemental topological
ferroelectric material. Three and four bilayers Bi films with polar structures
are ferroelectric-like elemental polar metals with topological nontrivial edge
states. For Ge and Sn, trivial elemental polar metals are predicted. Our work
reveals the possibility of design two-dimensional elemental topological
ferroelectrics and polar metals by stacking-engineering.Comment: 18 pages, 6 figure
Conductance of a quantum point contact in the presence of spin-orbit interaction
A recursive Green's function technique is developed to calculate the
spin-dependent conductance in mesoscopic structures. Using this technique, we
study the spin-dependent electronic transport of quantum point contacts in the
presence of the Rashba spin-orbit interaction. We observed that some
oscillations in the `quantized' conductance are induced by the spin-orbit
interaction, and indicated that the oscillations may stem from the spin-orbit
coupling associated multiple reflections. It is also indicated that the 0.7
structure of the conductance observed in mesoscopic experiments would not stem
from the spin-orbit interaction.Comment: 8 page
PO-188 Effects of Tai-Chi exercise on blood lipids, inflammatory factors and baPWV of middle-aged and elderly people
Objective To investigate the interventional effects of 12 months Tai-Chi exercise on blood lipids, inflammatory factors and the interventional mechanism of exercise in arteriosclerosis of middle-aged and elderly people
Methods 30 in middle-aged and elderly people with average age of 63.50±2.91 joined 12 months taijiquan exercise that conducted 60 minutes ecth time, six times per week. Left brachial-ankle pulse wave velocity (L-baPWV), right brachial-ankle pulse wave velocity(R-baPWV) , left ankle brachial index (L-ABI), right ankle brachial index(R-ABI), serum triglyceride(TG), total cholesterol(TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), interleukin 6 (IL-6) and hypersensitive c-reactive protein (hs-CRP) were detected at 3 time points including before exercise programme, by the end of exercise for 6th and 12th month.
Results ①Compared with pre-exercise, the R-baPWV and R-ABI of the elderly people were decreased at the end of the 6th month, and the L-baPWV, R-baPWV, R-ABI and L-ABI were decreased significantly at the end of the 12th month. ②Compared with pre-exercise, TC and LDL-c were declined markedly (P<0.01) at the end of the 6th and the 12th month, and there was no difference of the level of TG and LDL-c between pre-exercise and post-exercise.③Compared with before exercise, the subjects had significantly decreased IL-6 at the end of 6th months of exercise (P < 0.01), and the decrease of hs-CRP was not obvious. At the end of 12 th months, IL-6 and hs-CRP decreased significantly (P < 0.01). ④According to the correlation analysis, baPWV were positively correlated with TC, IL-6 and hs-CRP.
Conclusions 12 months of exercise intervention can effectively reduce the elderly baPWV and ABI level, improve the blood pressure, blood lipid and body inflammation levels, thus to prevent the happening of the atherosclerosis development plays an important role
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