Singular Effects of Spin-Flip Scattering on Gapped Dirac Fermions

We investigate the effects of spin-flip scattering on the Hall transport and spectral properties of gapped Dirac fermions. We find that in the weak scattering regime, the Berry curvature distribution is dramatically compressed in the electronic energy spectrum, becoming singular at band edges. As a result the Hall conductivity has a sudden jump (or drop) of $e^2/2h$ when the Fermi energy sweeps across the band edges, and otherwise is a constant quantized in units of $e^2/2h$. In parallel, spectral properties such as the density of states and spin polarization are also greatly enhanced at band edges. Possible experimental methods to detect these effects are discussed

Magnetodielectric effect of Bi6Fe2Ti3O18 film under an ultra-low magnetic field

Good quality and fine grain Bi6Fe2Ti3O18 magnetic ferroelectric films with single-phase layered perovskite structure have been successfully prepared via metal organic decomposition (MOD) method. Results of low-temperature magnetocapacitance measurements reveal that an ultra-low magnetic field of 10 Oe can produce a nontrivial magnetodielectric (MD) response in zero-field-cooling condition, and the relative variation of dielectric constants in magnetic field is positive, i.e., MD=0.05, when T<55K, but negative with a maximum of MD=-0.14 when 55K<T<190K. The magnetodielectric effect appears a sign change at 55K, which is due to transition from antiferromagnetic to weak ferromagnetic; and vanishes abruptly around 190K, which is thought to be associated with order-disorder transition of iron ion at B site of perovskite structures. The ultra-low-field magnetodielectric behaviour of Bi6Fe2Ti3O18 film has been discussed in the light of quasi-two-dimension unique nature of local spin order in ferroelectric film. Our results allow expectation on low-cost applications of detectors and switches for extremely weak magnetic fields in a wide temperature range 55K-190K.Comment: 10 pages 4 figures, planned to submit to J. Phys.: Condensed Matte

The first non-mammalian CXCR5 in a teleost fish: molecular cloning and expression analysis in grass carp (Ctenopharyngodon idella)

<p>Abstract</p> <p>Background</p> <p>Chemokines, a group of small and structurally related proteins, mediate chemotaxis of various cell types via chemokine receptors. In mammals, seven different CXC chemokine receptors denoted as CXCR1 to CXCR7 have been reported. However, the chemokine receptor CXCR5 has not been reported in other vertebrates.</p> <p>Results</p> <p>In the present study, the genomic sequence of CXCR5 was isolated from the grass carp <it>Ctenopharyngodon idella</it>. The cDNA sequence of grass carp CXCR5 (gcCXCR5) consists of 1518 bp with a 43 bp 5' untranslated region (UTR) and a 332 bp 3' UTR, with an open reading frame of 1143 bp encoding 381 amino acids which are predicted to have seven transmembrane helices. The characteristic residues (DRYLAIVHA) and conserved cysteine residues are located in the extracellular regions and in the third to seventh transmembrane domains. The deduced amino acid sequence shows 37.6-66.6% identities with CXCR5 of mammals, avian and other fish species. The grass carp gene consists of two exons, with one intervening intron, spaced over 2081 bp of genomic sequence. Phylogenetic analysis clearly demonstrated that the gcCXCR5 is clustered with those in other teleost fish and then in chicken and mammals. Real-time PCR analysis showed that gcCXCR5 was expressed in all tested organs/tissues and its expression level was the highest in trunk kidney, followed by in the spleen. The expression of gcCXCR5 was significantly modulated by immunostimulants such as peptidoglycan (PGN), lipopolysaccharide (LPS), polyinosinic-polycytidylic acid sodium salt (Poly I:C) and phytohaemagglutinin (PHA).</p> <p>Conclusion</p> <p>The cDNA and genomic sequences of CXCR5 have been successfully characterized in a teleost fish, the grass carp. The CXCR5 has in general a constitutive expression in organs/tissues examined, whereas its expression was significantly up-regulated in immune organs and down-regulated in brain, indicating its potential role in immune response and central nervous system.</p

Disaccharide combinations and the expression of enolase3 and plasma membrane Ca2+ ATPase isoform in sturgeon sperm cryopreservation

ContentsAcipenser sinensis and Acipenser dabryanus are critically endangered species, so germplasm conservation via cryopreservation of sperm is necessary. Disaccharides can act as membrane-impermeable cryoprotectants, and enolase3 (ENO3) and plasma membrane Ca2+ ATPase isoform (PMCA2) are proteins associated with sperm quality. We considered seven characteristics of sperm quality in cultured brood stock from A.sinensis and A.dabryanus. We tested use of sucrose or trehalose alone and in combination at different concentrations for cryopreservation of A.dabryanus sperm. A low concentration of sucrose plus trehalose (S15T15) was optimal. Mixing of the extender with sucrose, lactose, or trehalose alone or with pairwise mixtures revealed that a mixture of lactose and trehalose (L15T15) gave the best results for both A.sinensis and A.dabryanus. Enolase3 and PMCA2 expression levels were measured in cryopreserved A.sinensis sperm via Western blotting. Relative ENO3 and PMCA2 expression levels were examined, and the relationship between disaccharide composition, sperm quality and protein expression was explored in A.sinensis. The results showed that relative ENO3 and PMCA2 expression levels were the highest at L15T15 in cryopreserved A.sinensis sperm. There were significant positive correlations between ENO3 expression and percentage membrane integrity, and between PMCA2 expression and sperm motility parameters (percentage of motile sperm, curvilinear velocity, straight-line velocity and average path velocity; p&lt;.05) in cryopreserved A.sinensis sperm. Our results indicate the optimal disaccharide combination and concentrations for cryopreservation of A.sinensis and A.dabryanus sperm and suggest that ENO3 and PMCA2 expression levels could serve as a valuable indicator of sperm quality in A.sinensis.</p

Exposure to famine in early life and the risk of obesity in adulthood in Qingdao : Evidence from the 1959-1961 Chinese famine

Background and aims: We aimed to evaluate the association between famine exposure during early life and obesity and obesity(max) (obese at the highest weight) in adulthood. Methods and results: Data were from two population-based cross-sectional surveys conducted in 2006 and 2009 in Qingdao, China. A total of 8185 subjects born between 1/1/1941 and 12/31/1971 were categorized into unexposed (born between 01/01/1962 and 12/31/1971), fetal/ infant exposed (born between 01/01/1959 and 12/31/1961), childhood exposed (born between 01/01/1949 and 12/31/1958) and adolescence exposed (born between 01/01/1941 and 12/31/1948) according to their age when exposed to the Chinese famine from 1959 to 1961. Obesity was defined as BMI (body mass index) >= 28.0 and obesitymax was defined as BMImax (BMI at the highest weight) >= 28.0. We compared fetal/ infant exposed, childhood exposed and adolescence exposed to the unexposed using logistic regression models to assess the effect of famine exposure on later obesity and obesitymax. Fetal/infant exposed (OR = 1.59, P <0.001), childhood exposed (OR = 1.42, P <0.01) and adolescence exposed (OR = 1.86, P <0.01) all had higher risks of obesity than the unexposed. Exposure groups were more likely to be obese at their highest weight than the unexposed, and ORs (95%CIs) for obesitymax in the fetal/ infant exposed, childhood exposed and adolescence exposed were 1.49(1.20e1.86), 1.24(1.02e1.49) and 1.64 (1.40 e1.93), respectively. Similar results were found in both men and women. Conclusion: Exposure to famine in early life was associated with increased risks of obesity and obesitymax in adulthood. Preventing undernutrition in early life appears beneficial to reduce the prevalence of later obesity. (C) 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.Peer reviewe

State estimation for discrete-time neural networks with Markov-mode-dependent lower and upper bounds on the distributed delays

Copyright @ 2012 Springer VerlagThis paper is concerned with the state estimation problem for a new class of discrete-time neural networks with Markovian jumping parameters and mixed time-delays. The parameters of the neural networks under consideration switch over time subject to a Markov chain. The networks involve both the discrete-time-varying delay and the mode-dependent distributed time-delay characterized by the upper and lower boundaries dependent on the Markov chain. By constructing novel Lyapunov-Krasovskii functionals, sufficient conditions are firstly established to guarantee the exponential stability in mean square for the addressed discrete-time neural networks with Markovian jumping parameters and mixed time-delays. Then, the state estimation problem is coped with for the same neural network where the goal is to design a desired state estimator such that the estimation error approaches zero exponentially in mean square. The derived conditions for both the stability and the existence of desired estimators are expressed in the form of matrix inequalities that can be solved by the semi-definite programme method. A numerical simulation example is exploited to demonstrate the usefulness of the main results obtained.This work was supported in part by the Royal Society of the U.K., the National Natural Science Foundation of China under Grants 60774073 and 61074129, and the Natural Science Foundation of Jiangsu Province of China under Grant BK2010313

Gluon fragmentation to ^3D_J quarkonia

We present a calculation of the leading order QCD fragmentation functions for gluons to split into spin-triplet D-wave quarkonia. We apply them to evaluate the gluon fragmentation contributions to inclusive ^3D_J quarkonium production at large transverse momentum processes like the Tevatron and find that the D-wave quarkonia, especially the charmonium 2^{--} state, could be observed through color-octet mechanism with present luminosity. Since there are distinctively large gaps between the contributions of two different (i.e, color-singlet and color-octet) quarkonium production mechanisms, our results may stand as a unique test to NRQCD color-octet quarkonium production mechanism.Comment: 15 pages in LaTex (2 figures in PS-file

What Makes Theatrical Performances Successful in China's Tourism Industry?

This study aims to explore the factors affecting the success of a popular tourist product, namely, theatrical performance, within the context of China's tourism industry and develop a model based on previously successful productions. Using qualitative software, 22 Chinese-language articles on theatrical performances are analyzed to generate a list of success factors, classified as internal and external. The internal factors are storyline and performing, market positioning and marketing strategy, investment and financial support, operation and management, performing team, outdoor venue, indoor/outdoor stage supporting facilities, continuous improvement, and production team. The external factors are collaboration between cultural industries and local tourism, government support, privatization, and social and cultural effect. This study also provides suggestions for the future development of theatrical performances in China

Colposcopic accuracy in diagnosing squamous intraepithelial lesions: a systematic review and meta-analysis of the International Federation of Cervical Pathology and Colposcopy 2011 terminology

Background Colposcopy is an important tool in diagnosing cervical cancer, and the International Federation of Cervical Pathology and Colposcopy (IFCPC) issued the latest version of the guidelines in 2011. This study aims to systematically assess the accuracy of colposcopy in predicting low-grade squamous intraepithelial lesions or worse (LSIL+) / high-grade squamous intraepithelial lesions or worse (HSIL+) under the 2011 IFCPC terminology. Methods We performed a systematic review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched for studies about the performance of colposcopy in diagnosing cervical intraepithelial neoplasia under the new IFCPC colposcopy terminology from PubMed, Embase, Web of Science and the Cochrane database. Data were independently extracted by two authors and an overall diagnostic performance index was calculated under two colposcopic thresholds. Results In total, fifteen articles with 22,764 participants in compliance with the criteria were included in meta-analysis. When colposcopy was used to detect LSIL+, the combined sensitivity and specifcity were 0.92 (95% CI 0.88–0.95) and 0.51 (0.43–0.59), respectively. When colposcopy was used to detect HSIL+, the combined sensitivity and specifcity were 0.68 (0.58–0.76) and 0.93 (0.88–0.96), respectively. Conclusion In accordance with the 2011 IFCPC terminology, the accuracy of colposcopy has improved in terms of both sensitivity and specifcity. Colposcopy is now more sensitive with LSIL+ taken as the cut-of value and is more specifc to HSIL+. These fndings suggest we are avoiding under- or overdiagnosis both of which impact on patients’ well-being