2,178 research outputs found
Sex-related difference in food-anticipatory activity of mice
The expression of food-anticipatory activity (FAA) is induced by restricted feeding (RF), and its entrainment requires food-entrainable oscillators, the neuroanatomical basis of which is currently unclear. Although RF impacts various hormones, sex-related differences in FAA are unclear. 'Here, we report significantly more food-anticipatory wheel-running activity in male than in female mice during RF. In parallel with the sex-related difference in FAA, male and female mice display different food intake and body weight in response to RF. Since gonadal hormones could be involved in the sex-specific difference in FAA, we compared sham and gonadectomized male and female wild-type mice. In gonadectomized mice, the sex difference in FAA was abolished, indicating a role for gonadal hormones in FAA. Further, plasma concentrations of the hormone ghrelin were higher in female than in male mice during ad libitum (AL) feeding, and RF induced a temporal advance in its peak in both sexes. RF also shifted the expression peak of the circadian gene mPer1 in the hippocampus and liver, although no sex difference was found in either the level or the cyclic phase of its expression. Per1(Brdm1) mutant mice were still sexually dimorphic for FAA, but diminished FAA was noted in both male and female Per2(Brdm1) mutant mice. In summary, our results imply that gonadal hormones contribute to the sex difference in FAA, possibly through modulating ghrelin activity. (C) 2015 Published by Elsevier Inc
Proteomic and Physiological Analyses Reveal Putrescine Responses in Roots of Cucumber Stressed by NaCl
Poly[[[diaquacobalt(II)]-bis[μ2-1,1′-(butane-1,4-diyl)diimidazole-κ2 N 3:N 3′]] dinitrate]
In the title compound, {[Co(C10H14N4)2(H2O)2](NO3)2}n, the CoII ion lies on an inversion center and is six-coordinated in an octahedral environment by four N atoms from four different 1,1′-butane-1,4-diyldiimidazole ligands and two O atoms from the two water molecules. The CoII atoms are bridged by ligands, generating a two-dimensional (4,4)-network. Adjacent fishnet planes are linked to the nitrate anions via O—H⋯O hydrogen bonds, forming a three-dimensional supramolecular structure
Poly[[[diaquacobalt(II)]-bis[μ2-1,1′-(butane-1,4-diyl)diimidazole-κ2 N 3:N 3′]] dichloride tetrahydrate]
In the title compound, {[Co(C10H14N4)2(H2O)2]Cl2·4H2O}n, the CoII atom and the mid-point of the 1,1′-butane-1,4-diyldiimidazole ligands lie on inversion centers. The CoII atom is six-coordinated in a slightly distorted octahedral environment by four N atoms from four different ligands and by two O atoms from the water molecules. The CoII atoms are bridged by the ligands into a (4,4) net. Adjacent nets are linked to the chloride anions and uncoordinated water molecules via O—H⋯Cl and O—H⋯O hydrogen bonds, generating a three-dimensional supramolecular structure
Facile syntheses of monodisperse ultrasmall Au clusters
During our effort to synthesize the tetrahedral Au 20 cluster, we found a facile synthetic route to prepare monodisperse suspensions of ultrasmall Au clusters Au N (N < 12) using diphosphine ligands. In our monophasic and single-pot synthesis, a Au precursor ClAu(I)PPh 3 (Ph ) phenyl) and a bidentate phosphine ligand P(Ph) 2 (CH 2 ) M P(Ph) 2 are dissolved in an organic solvent. Au(I) is reduced slowly by a borane-tert-butylamine complex to form Au clusters coordinated by the diphosphine ligand. The Au clusters are characterized by both high-resolution mass spectrometry and UV-vis absorption spectroscopy. We found that the mean cluster size obtained depends on the chain length M of the ligand. In particular, a single monodispersed Au 11 cluster is obtained with the P(Ph) 2 (CH 2 ) 3 P(Ph) 2 ligand, whereas P(Ph) 2 (CH 2 ) M P(Ph) 2 ligands with M ) 5 and 6 yield Au 10 and Au 8 clusters. The simplicity of our synthetic method makes it suitable for large-scale production of nearly monodisperse ultrasmall Au clusters. It is suggested that diphosphines provide a set of flexible ligands to allow size-controlled synthesis of Au nanoparticles
Large spin Hall conductivity and excellent hydrogen evolution reaction activity in unconventional PtTe1.75 monolayer
Two-dimensional (2D) materials have gained lots of attention due to the
potential applications. In this work, we propose that based on first-principles
calculations, the (22) patterned PtTe monolayer with kagome lattice
formed by the well-ordered Te vacancy (PtTe) hosts large spin Hall
conductivity (SHC) and excellent hydrogen evolution reaction (HER) activity.
The unconventional nature relies on the band representation (BR) of the
highest valence band without SOC. The large SHC comes from the Rashba
spin-orbit coupling (SOC) in the noncentrosymmetric structure induced by the Te
vacancy. Even though it has a metallic SOC band structure, the
invariant is well defined due to the existence of the direct band gap and is
computed to be nontrivial. The calculated SHC is as large as 1.25 at the Fermi level (). By tuning the
chemical potential from to eV, it varies rapidly and
monotonically from to 3.1. In addition, we also find the Te vacancy in the patterned
monolayer can induce excellent HER activity. Our results not only offer a new
idea to search 2D materials with large SHC, i.e., by introducing
inversion-symmetry breaking vacancies in large SOC systems, but also provide a
feasible system with tunable SHC (by applying gate voltage) and excellent HER
activity
The Viscoelasticity Model of Corn Straw under the Different Moisture Contents
Viscoelastic model of corn straw, based on different moisture contents, is set up to characterise the deformation through three-point bending test. The model contains a linear elastic element, a damping element, and a nonlinear elastic element. The parameters of the model are determined according to the features of three-point bending test curve and characteristic of the model. The relationships between mechanical properties, energy absorption behavior of corn stalk, and moisture content have been, respectively, analysed. And regression analysis and curve fitting have been conducted based on various parameters and moisture contents with Matlab. These parameters provide the basis for straw crushing equipment design
A Mid-infrared Flare in the Active Galaxy MCG-02-04-026: Dust Echo of a Nuclear Transient Event
We report the discovery of a mid-infrared (MIR) flare using Wide field Infrared Survey Explorer data in the center of the nearby Seyfert 1.9 galaxy MCG-02-04-026. The MIR flare began in the first half of 2014, peaked around the end of 2015, and faded in 2017. During these years, energy of more than 7 × 10⁵⁰ erg was released in the infrared, and the flare's MIR color was generally turning red. We detected neither optical nor ultraviolet (UV) variation corresponding to the MIR flare based on available data. We explained the MIR flare using a dust echo model in which the radiative transfer is involved. The MIR flare can be well explained as thermal reradiation from dust heated by UV–optical photons of a primary nuclear transient event. Although the transient event was not seen directly owing to dust obscuration, we can infer that it may produce a total energy of at least ~10⁵¹ erg, most of which was released in less than ~3 yr. The nature of the transient event could be a stellar tidal disruption event by the central supermassive black hole (SMBH), or a sudden enhancement of the existing accretion flow onto the SMBH, or a supernova that was particularly bright
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