3,371 research outputs found
Bis(2,2′-bipyridine-κ2 N,N′)(thioÂcyanato-κN)copper(II) perchlorate
The asymmetric unit of title compound, [Cu(NCS)(C10H8N2)2]ClO4, contains a bisÂ(2,2′-bipyridine)(isothioÂcyanato)copper(II) cation and a perchlorate anion. In the cation, the Cu2+ ion is coordinated by four N atoms from two bidentate 2,2′-bipyridine molÂecules and an N atom from an isothioÂcyanate anion, resulting in a distorted CuN5 pyramidal configuration. The crystal structure is stabilized by weak interÂmolecular C—H⋯O and C—H⋯S hydrogen bonds, and weak π–π interÂactions between 2,2′-bipyridine rings [centroid–centroid distance = 3.908 (4) Å]. The perchlorate counteranion is disordered over two positions in a 0.66:0.34 ratio
The Insect Fascicle Morphology Research and Bionic Needle Pierced Mechanical Mechanism Analysis
In this paper, mosquito and cicadas two kinds of insects fascicle were studied, and observed the fascicle surface morphology and distribution through scanning electron microscopy, discussed the height of the six parameters of sawtooth and analyzed quantitatively, compared the two types of fascicle in micro-structure size, and shape, the experiment results show that there are obviously different among the two mouth fascicle morphological structure. Triangular sawtooth are all clearly visible in the two kinds of insect fascicle, in which the mosquito has the small microstructure, and the cicada has the larger one; microstructure of mosquitoes tilt to the rear part of the fascicle, while the microstructure of cicada is symmetric on bottom corner. Based on non-smooth surface structure of fascicle obvious principles of drag reduction effect, the model of drag reduction bionic syringe is proposed, Designed a bionic drag painless needles, and simulated needle piercing power is also measured. Bionic needle surface microstructure can help reduce the needle to decrease the contact area, form rolling, friction, and thus reduce the resistance to needle piercing. Bionic needle has been proved that its puncture resistance is less than smooth one consequently has significant drag reduction effects. Keywords: Insects fascicle; surface morphology; bionic needles; drag reductio
Nucleon-nucleon interaction in the - coupled channel for a pion mass of 469 MeV
In this work, we apply the relativistic chiral nuclear force to describe the
state-of-the-art lattice simulations of the nucleon-nucleon scattering
amplitude. In particular, we focus on the - coupled channel for a
pion mass of 469 MeV. We show that at leading order the relativistic chiral
nuclear force can only describe and up to
MeV, while at the next-to-leading order it can do
much better up to MeV. However, at the
next-to-next-to-leading order, the description deteriorates, which can be
attributed to the fact that the pion-mass dependence of the pion-nucleon
couplings may not be negligible. Furthermore, all the studies
consistently yield negative , contrary to the lattice QCD results
which are positive but consistent with zero. The present study is relevant to a
better understanding of the lattice QCD nucleon-nucleon force and more general
baryon-baryon interactions.Comment: Accepted for publication in PL
Genome sequence and genetic linkage analysis of Shiitake mushroom _Lentinula edodes_
_Lentinula edodes_ (Shiitake/Xianggu) is an important cultivated mushroom. Understanding the genomics and functional genomics of _L. edodes_ allows us to improve its cultivation and quality. Genome sequence is a key to develop molecular genetic markers for breeding and genetic manipulation. We sequenced the genome of _L. edodes_ monokaryon L54A using Roche 454 and ABI SOLiD genome sequencing. Sequencing reads of about 1400Mb were de novo assembled into a 40.2 Mb genome sequence. We compiled the genome sequence into a searchable database with which we have been annotating the genes and analyzing the metabolic pathways. In addition, we have been using many molecular techniques to analyze genes differentially expressed during development. Gene ortholog groups of _L. edodes_ genome sequence compared across genomes of several fungi including mushrooms identified gene families unique to mushroom-forming fungi. We used a mapping population of haploid basidiospores of dikaryon L54 for genetic linkage analysis. High-quality variations such as single nucleotide polymorphisms, insertions, and deletions of the mapping population formed a high-density genetic linkage map. We compared the linkage map to the _L. edodes_ L54A genome sequence and located selected quantitative trait loci. The Shiitake community will benefit from these resources for genetic studies and breeding.

Observation of Majorana fermions with spin selective Andreev reflection in the vortex of topological superconductor
Majorana fermion (MF) whose antiparticle is itself has been predicted in
condensed matter systems. Signatures of the MFs have been reported as zero
energy modes in various systems. More definitive evidences are highly desired
to verify the existence of the MF. Very recently, theory has predicted MFs to
induce spin selective Andreev reflection (SSAR), a novel magnetic property
which can be used to detect the MFs. Here we report the first observation of
the SSAR from MFs inside vortices in Bi2Te3/NbSe2 hetero-structure, in which
topological superconductivity was previously established. By using
spin-polarized scanning tunneling microscopy/spectroscopy (STM/STS), we show
that the zero-bias peak of the tunneling differential conductance at the vortex
center is substantially higher when the tip polarization and the external
magnetic field are parallel than anti-parallel to each other. Such strong spin
dependence of the tunneling is absent away from the vortex center, or in a
conventional superconductor. The observed spin dependent tunneling effect is a
direct evidence for the SSAR from MFs, fully consistent with theoretical
analyses. Our work provides definitive evidences of MFs and will stimulate the
MFs research on their novel physical properties, hence a step towards their
statistics and application in quantum computing.Comment: 4 figures 15 page
Study on shear resistance of full-scale PC box girder reinforced by SPCCS method
Steel plate and concrete composite strengthening (SPCCS) method is developed on the basis of steel and concrete composite girder, the process of which mainly includes welding studs on the reinforcing steel plates, planting rebars in the original concrete, and casting concrete between the original structure and steel plates, thus the new and existing concrete can work together. It can improve both the bearing capacity and stiffness of bridge significantly. In order to investigate the shear resistance of concrete girder reinforced by SPCCS method, two full-scale damaged box girder released from an actual bridge are tested for contrast, one without reinforcement and the other is reinforced by SPCCS method. The shear mechanical behavior and failure mode before and after reinforcement are obtained and analyzed. Furthermore, the shear mechanism and calculation formula of shear capacity for box girder reinforced by SPCCS method are presented. The comparisons show that the calculation results are in good agreement with the test results
Transcriptional Profiling of Protein Expression Related Genes of Pichia pastoris under Simulated Microgravity
The physiological responses and transcription profiling of Pichia pastoris GS115 to simulated microgravity (SMG) were substantially changed compared with normal gravity (NG) control. We previously reported that the recombinant P. pastoris grew faster under SMG than NG during methanol induction phase and the efficiencies of recombinant enzyme production and secretion were enhanced under SMG, which was considered as the consequence of changed transcriptional levels of some key genes. In this work, transcriptiome profiling of P. pastoris cultured under SMG and NG conditions at exponential and stationary phases were determined using next-generation sequencing (NGS) technologies. Four categories of 141 genes function as methanol utilization, protein chaperone, RNA polymerase and protein transportation or secretion classified according to Gene Ontology (GO) were chosen to be analyzed on the basis of NGS results. And 80 significantly changed genes were weighted and estimated by Cluster 3.0. It was found that most genes of methanol metabolism (85% of 20 genes) and protein transportation or secretion (82.2% of 45 genes) were significantly up-regulated under SMG. Furthermore the quantity and fold change of up-regulated genes in exponential phase of each category were higher than those of stationary phase. The results indicate that the up-regulated genes of methanol metabolism and protein transportation or secretion mainly contribute to enhanced production and secretion of the recombinant protein under SMG
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