bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhomogeneous chemical enrichment in the Galactic Halo
Authors: Kobayashi Chiaki 
Published: May 2016

AbstractIn a galaxy, chemical enrichment takes place in an inhomogeneous fashion, and the Galactic Halo is one of the places where the inhomogeneous effects are imprinted and can be constrained from observations. I show this using my chemodynamical simulations of Milky Way type galaxies. The scatter in the elemental abundances originate from radial migration, merging/accretion of satellite galaxies, local variation of star formation and chemical enrichment, and intrinsic variation of nucleosynthesis yields. In the simulated galaxies, there is no strong age-metallicity relation. This means that the most metal-poor stars are not always the oldest stars, and can be formed in chemically unevolved clouds at later times. The long-lifetime sources of chemical enrichment such as asymptotic giant branch stars or neutron star mergers can contribute at low metallicities. The intrinsic variation of yields are important in the early Universe or metal-poor systems such as in the Galactic halo. The carbon enhancement of extremely metal-poor (EMP) stars can be best explained by faint supernovae, the low [α/Fe] ratios in some EMP stars naturally arise from low-mass (~ 13 - 15M⊙) supernovae, and finally, the [α/Fe] knee in dwarf spheroidal galaxies can be produced by subclasses of Type Ia supernovae such as SN 2002cx-like objects and sub-Chandrasekhar mass explosions.
Searching for chemical relics of first stars with LAMOST and Subaru
Authors: Li Haining , Aoki Wako , Zhao Gang , Honda Satoshi , Christlieb Norbert , Suda Takuma 
Published: May 2016

AbstractWe report progresses of a joint project on searching for extremely metal-poor (EMP) stars based on LAMOST survey and Subaru follow-up observation. Follow-up high-resolution snapshot spectra have been obtained for 70 objects, resulting in 42 EMP stars. A number of chemically interesting objects have already been identified, including (1) Two UMP (ultra metal-poor) stars with [Fe/H] ~ −4.0. One of them is the second UMP turnoff star with Li detection. (2) A super Li-rich (A(Li) ~ 3.1) EMP giant. This is the most metal-poor and extreme example of Li enhancement in giants known to date, and will shed light on Li production during the evolution of red giants. (3) A few EMP stars showing extreme overabundance in heavy elements. Detailed abundances of these extreme objects and statistics obtained by the large sample of EMP stars will provide important constraints on the Galactic halo formation.
Is low-protein diet a possible risk factor of malnutrition in chronic kidney disease patients?
Authors: Noce A , Vidiri M F , Marrone G , Moriconi E , Bocedi A , Capria A , Rovella V , Ricci G , De Lorenzo A , Di Daniele N 
Published: May 2016

AbstractChronic kidney disease (CKD) is becoming increasingly widespread in the world. Slowing its progression means to prevent uremic complications and improve quality of life of patients. Currently, a low-protein diet (LPD) is one of the tools most used in renal conservative therapy but a possible risk connected to LPD is protein-energy wasting. The aim of this study is evaluate the possible correlation between LPD and malnutrition onset. We enrolled 41 CKD patients, stages IIIb/IV according to K-DIGO guidelines, who followed for 6 weeks a diet with controlled protein intake (recommended dietary allowance 0.7 g per kilogram Ideal Body Weight per day of protein). Our patients showed a significant decrease of serum albumin values after 6 weeks of LDP (T2) compared with baseline values (T0) (P=0.039), whereas C-reactive protein increased significantly (T0 versus T2; P=0.131). From body composition analysis, a significant impairment of fat-free mass percentage at the end of the study was demonstrated (T0 versus T2; P=0.0489), probably related to total body water increase. The muscular mass, body cell mass and body cell mass index are significantly decreased after 6 weeks of LDP (T2). The phase angle is significantly reduced at the end of the study compared with basal values (T0 versus T2; P=0.0001, and T1 versus T2; P=0.0015). This study indicated that LPD slows down the progression of kidney disease but worsens patients' nutritional state.
Spontaneous helix formation in non-chiral bent-core liquid crystals with fast linear electro-optic effect
Authors: Sreenilayam Sithara P. , Panarin Yuri P. , Vij Jagdish K. , Panov Vitaly P. , Lehmann Anne , Poppe Marco , Prehm Marko , Tschierske Carsten 
Published: May 2016

AbstractLiquid crystals (LCs) represent one of the foundations of modern communication and photonic technologies. Present display technologies are based mainly on nematic LCs, which suffer from limited response time for use in active colour sequential displays and limited image grey scale. Herein we report the first observation of a spontaneously formed helix in a polar tilted smectic LC phase (SmC phase) of achiral bent-core (BC) molecules with the axis of helix lying parallel to the layer normal and a pitch much shorter than the optical wavelength. This new phase shows fast (∼30 μs) grey-scale switching due to the deformation of the helix by the electric field. Even more importantly, defect-free alignment is easily achieved for the first time for a BC mesogen, thus providing potential use in large-scale devices with fast linear and thresholdless electro-optical response.
MiR-186 inhibited aerobic glycolysis in gastric cancer via HIF-1α regulation
Authors: Liu L , Wang Y , Bai R , Yang K , Tian Z 
Published: May 2016

AbstractDeregulation of microRNAs in human malignancies has been well documented, among which microRNA-186 (miR-186) has an antiproliferative role in some carcinomas. Here we demonstrate that low expression of miR-186 facilitates aerobic glycolysis in gastric cancer. MiR-186 suppresses cell proliferation induced by hypoxia inducible factor 1 alpha (HIF-1α) in gastric cancer cell lines MKN45 and SGC7901. Cellular glycolysis, including cellular glucose uptake, lactate, ATP/ADP and NAD+/NADH ratios, are also inhibited by miR-186. The negative regulation of miR-186 on HIF-1α effects its downstream targets, including programmed death ligand 1 and two glycolytic key enzymes, hexokinase 2 and platelet-type phosphofructokinase. The antioncogenic effects of miR-186 are proved by in vivo xenograft tumor experiment. The results demonstrate that the miR-186/HIF-1α axis has an antioncogenic role in gastric cancer.
The effect of ageing on the mechanical properties of the silk of the bridge spider Larinioides cornutus (Clerck, 1757)
Authors: Lepore Emiliano , Isaia Marco , Mammola Stefano , Pugno Nicola 
Published: May 2016

AbstractSpider silk is regarded as one of the best natural polymer fibers especially in terms of low density, high tensile strength and high elongation until breaking. Since only a few bio-engineering studies have been focused on spider silk ageing, we conducted nano-tensile tests on the vertical naturally spun silk fibers of the bridge spiderLarinioides cornutus(Clerck, 1757) (Arachnida, Araneae) to evaluate changes in the mechanical properties of the silk (ultimate stress and strain, Young’s modulus, toughness) over time. We studied the natural process of silk ageing at different time intervals from spinning (20 seconds up to one month), comparing silk fibers spun from adult spiders collected in the field. Data were analyzed using Linear Mixed Models. We detected a positive trend versus time for the Young’s modulus, indicating that aged silks are stiffer and possibly less effective in catching prey. Moreover, we observed a negative trend for the ultimate strain versus time, attesting a general decrement of the resistance force. These trends are interpreted as being due to the drying of the silk protein chains and the reorientation among the fibers.
Characterization and Small RNA Content of Extracellular Vesicles in Follicular Fluid of Developing Bovine Antral Follicles
Authors: Navakanitworakul Raphatphorn , Hung Wei-Ting , Gunewardena Sumedha , Davis John S. , Chotigeat Wilaiwan , Christenson Lane K. 
Published: May 2016

AbstractExosomes and microvesicles (i.e., extracellular vesicles: EVs) have been identified within ovarian follicular fluid and recent evidence suggests that EVs are able to elicit profound effects on ovarian cell function. While existence of miRNA within EVs has been reported, whether EV size and concentration as well as their cargos (i.e., proteins and RNA) change during antral follicle growth remains unknown. Extracellular vesicles isolated from follicular fluid of small, medium and large bovine follicles were similar in size, while concentration of EVs decreased progressively as follicle size increased. Electron microscopy indicated a highly purified population of the lipid bilayer enclosed vesicles that were enriched in exosome biomarkers including CD81 and Alix. Small RNA sequencing identified a large number of known and novel miRNAs that changed in the EVs of different size follicles. Ingenuity Pathway Analysis (IPA) indicated that miRNA abundant in small follicle EV preparations were associated with cell proliferation pathways, while those miRNA abundant in large follicle preparations were related to inflammatory response pathways. These studies are the first to demonstrate that EVs change in their levels and makeup during antral follicle development and point to the potential for a unique vesicle-mediated cell-to-cell communication network within the ovarian follicle.
The characteristics of circular disposable devices and in situ devices for optimizing male circumcision: a network meta-analysis
Authors: Fan Yu , Cao Dehong , Wei Qiang , Tang Zhuang , Tan Ping , Yang Lu , Liu Liangren , Liu Zhenhua , Li Xiang , Xue Wenbin 
Published: May 2016

AbstractIn situ device (ISD) and circular disposable device (CDD) are used for optimizing male circumcision (MC), but evidence to explore the characteristics of these two devices is insufficient. In order to explore this issue systematically and provide reliable evidence, ten published randomized controlled trials (RCTs) exploring the safety and efficacy of ISDs and CDDs were included (involving 4649 men). Moderate quality of the RCTs included was found after assessment. Pairwise meta-analyses and network meta-analyses were processed in stata 13.0 and AIDDS v1.16.6 respectively. According to the outcomes that were statistically significant in both pairwise and network meta-analyses, ISD was found to have less intraoperative blood loss (IB), less operative time (OT) and less incidence of wound bleeding (WB) than conventional circumcision (CC); ISD was found to have less WB but more wound healing time (WHT) than CDD; CDD was found to have less IB and less OT than CC. CDD tended to have the best wound healing condition and least pain experience; ISD tended to have the least IB, least OT, least WB, and highest satisfaction rate. With their own superiorities in many aspects, CDD and ISD are both safe and effective devices for optimizing MC.
miRNA let-7b modulates macrophage polarization and enhances tumor-associated macrophages to promote angiogenesis and mobility in prostate cancer
Authors: Wang Zhigang , Xu Lu , Hu Yinying , Huang Yanqin , Zhang Yujuan , Zheng Xiufen , Wang Shanshan , Wang Yifan , Yu Yanrong , Zhang Meng , Yuan Keng , Min Weiping 
Published: May 2016

AbstractMacrophage polarization is a highly plastic physiological process that responds to a variety of environmental factors by changing macrophage phenotype and function. Tumor-associated macrophages (TAMs) are generally recognized as promoting tumor progression. As universal regulators, microRNAs (miRNAs) are functionally involved in numerous critical cellular processes including macrophage polarization. Let-7b, a miRNA, has differential expression patterns in inflamed tissues compared with healthy controls. However, whether and how miRNA let-7b regulates macrophage phenotype and function is unclear. In this report, we find that up-regulation of let-7b is characteristic of prostatic TAMs and down-regulation of let-7b in TAMs leads to changes in expression profiles of inflammatory cytokines, such as IL-12, IL-23, IL-10 and TNF-α. As a result, TAMs treated with let-7b inhibitors reduce angiogenesis and prostate carcinoma (PCa) cell mobility. Let-7b may play a vital role in regulating macrophage polarization, thus modulating the prognosis of prostate cancer.
Loss of the 14-3-3σ is essential for LASP1-mediated colorectal cancer progression via activating PI3K/AKT signaling pathway
Authors: Shao Ziyun , Cai Yanjun , Xu Lijun , Yao Xueqing , Shi Jiaolong , Zhang Feifei , Luo Yuhao , Zheng Kehong , Liu Jian , Deng Fengliu , Li Rui , Zhang Lanzhi , Wang Hui , Li Mingyi , Ding Yanqing , Zhao Liang 
Published: May 2016

AbstractLIM and SH3 protein 1 (LASP1) can promote colorectal cancer (CRC) progression and metastasis, but the direct evidence that elucidates the molecular mechanism remains unclear. Here, our proteomic data showed that LASP1 interacted with 14-3-3σ and decreased the expression of 14-3-3σ in CRC. Deletion of 14-3-3σ was required for LASP1-mediated CRC cell aggressiveness. In vitro gain- and loss-of-function assays showed that 14-3-3σ suppressed the ability of cell migration and decreased the phosphorylation of AKT in CRC cells. We further observed clearly co-localization between AKT and 14-3-3σ in CRC cells. Treatment of PI3K inhibitor LY294002 markedly prevented phosphorylation of AKT and subsequently counteract aggressive phenotype mediated by siRNA of 14-3-3σ. Clinically, 14-3-3σ is frequently down-regulated in CRC tissues. Down-regulation of 14-3-3σ is associated with tumor progression and poor prognosis of patients with CRC. Multivariate analysis confirmed low expression of 14-3-3σ as an independent prognostic factor for CRC. A combination of low 14-3-3σ and high LASP1 expression shows a worse trend with overall survival of CRC patients. Our research paves the path to future investigation of the LASP1-14-3-3σ axis as a target for novel anticancer therapies of advanced CRC.
Dynamic Onset of Feynman Relation in the Phonon Regime
Authors: Li Y. , Zhu C. J. , Hagley E. W. , Deng L. 
Published: May 2016

AbstractThe Feynman relation, a much celebrated condensed matter physics gemstone for more than 70 years, predicts that the density excitation spectrum and structure factor of a condensed Bosonic system in the phonon regime drops linear and continuously to zero. Until now, this widely accepted monotonic excitation energy drop as the function of reduced quasi-momentum has never been challenged in a spin-preserving process. We show rigorously that in a light-matter wave-mixing process in a Bosonic quantum gas, an optical-dipole potential arising from the internally-generated field can profoundly alter the Feynman relation and result in a new dynamic relation that exhibits an astonishing non-Feynman-like onset and cut-off in the excitation spectrum of the ground state energy of spin-preserving processes. This is the first time that a nonlinear optical process is shown to actively and significantly alter the density excitation response of a quantum gas. Indeed, this dynamic relation with a non-Feynman onset and cut-off has no correspondence in either nonlinear optics of a normal gas or a phonon-based condensed matter Bogoliubov theory.
1.3.2 Resolution of Alcohols, Amines, Acids, and Esters by Nonhydrolytic Processes
Authors: Rodríguez-Mata M. , Gotor-Fernández V. 
Published: May 2016

AbstractThe use of hydrolases has become a conventional process in organic synthesis, not only for the preparation of optically pure compounds, but also for regio- and chemoselective processes. Their utility for selective transformations under mild reaction conditions make hydrolases attractive catalysts for performing certain transformations that are difficult to achieve by nonenzymatic strategies. Nowadays, many companies use lipases for the preparation of high-added-value compounds and pharmaceuticals because of the advantages of hydrolase-catalyzed processes, which include cost and environmental benefits. Their commercial availability, lack of cofactor dependency, and activity in both aqueous and organic media has allowed the development of asymmetric transformations which are summarized in this chapter. After a brief general introduction discussing the potential of hydrolases in organic synthesis, asymmetric reverse hydrolytic processes are analyzed, substituting the conventional hydrolase nucleophile, water, for other species such as alcohols, amines, esters, or ammonia. The kinetic resolution and dynamic kinetic resolution reactions of alcohols and amines are presented, using esters or carbonates for the production of esters, amides, and carbamates in optically active form. Finally, the resolution of carboxylic acids or esters is described via less-employed interesterification, aminolysis, and ammonolysis processes.
1.4.5 Hydrolysis of Hydantoins, Dihydropyrimidines, and Related Compounds
Authors: Slomka C. , Engel U. , Syldatk C. , Rudat J. 
Published: May 2016

AbstractProviding advantages including high chemo-, regio-, and enantioselectivity as well as mild reaction conditions, biocatalytic reaction systems are becoming increasingly important for the synthesis of chiral fine chemicals. This chapter focuses on hydantoins and related compounds as promising substrates for the synthesis of optically pure amino acids and on the enzymes involved in these processes. In particular, the production of D-amino acids, such as D-4-hydroxyphenylglycine, via the so-called “hydantoinase process” is now well established. Many investigations regarding the synthesis of L-amino acids with the help of this process have also been carried out. A further interesting application is the synthesis of β-amino acids, which are gaining importance in the pharmaceutical industry due to their special structure. Different possibilities for the application of modified hydantoinase processes are discussed, in which dihydropyrimidines serve as substrates for β-amino acid synthesis. Moreover, various methods to improve the synthesis of amino acids are described.
1.6.2 Glycosyltransferases
Authors: Voglmeir J. , Flitsch S. L. 
Published: May 2016

AbstractThe stereo- and regioselective properties and the high selectivity of glycosyltransferases toward donor and acceptor substrates make these enzymes highly attractive for synthetic applications. Various examples of recombinantly expressed glycosyltransferases demonstrate the versatility of both in vivo and in vitro syntheses of oligosaccharides from milligram to kilogram scale. However, due to the enormous variety of carbohydrate structures in living organisms, to date only a small proportion of carbohydrate epitopes have been synthesized in a routine manner. This chapter summarizes recent approaches to the application of glycosyltransferases in both preparative sugar synthesis and biotransformation.
Collateral, Taxes, and Leverage
Authors: Li Shaojin , Whited Toni M. , Wu Yufeng 
Published: May 2016

Abstract
We quantify the importance of collateral versus taxes for firms' capital structures. We estimate a dynamic model in which a taxable firm seeks financing for investment, and a dynamic contracting environment motivates endogenous collateral constraints. Optimal leverage stays a safe distance from the constraint, balancing the tax benefit of debt with the cost of lost financial flexibility. We estimate this flexibility cost to be 7.2% of firm assets, a percentage that is comparable to the tax benefit. Models with different tax rates fit the data equally well, and leverage responds to the tax rate only when taxes are low.
Received January 20, 2015; accepted January 8, 2016 by Editor Itay Goldstein.
Gene- and pathway-based association tests for multiple traits with GWAS summary statistics
Authors: Kwak Il-Youp , Pan Wei 
Published: May 2016

AbstractTo identify novel genetic variants associated with complex traits and to shed new insights on underlying biology, in addition to the most popular single SNP-single trait association analysis, it would be useful to explore multiple correlated (intermediate) traits at the gene-or pathway-level by mining existing single GWAS or meta-analyzed GWAS data. For this purpose, we present an adaptive gene-based test and a pathway-based test for association analysis of multiple traits with GWAS summary statistics. The proposed tests are adaptive at both the SNP-and trait-levels; that is, they account for possibly varying association patterns (e.g. signal sparsity levels) across SNPs and traits, thus maintaining high power across a wide range of situations. Furthermore, the proposed methods are general: they can be applied to mixed types of traits, and to Z-statistics or p-values as summary statistics obtained from either a single GWAS or a meta-analysis of multiple GWAS. Our numerical studies with simulated and real data demonstrated the promising performance of the proposed methods.The methods are implemented in R package aSPU, freely and publicly available on CRAN at:https://cran.r-project.org/web/packages/aSPU/.
Detection of human adaptation during the past 2,000 years
Authors: Field Yair , Boyle Evan A , Telis Natalie , Gao Ziyue , Gaulton Kyle J. , Golan David , Yengo Loic , Rocheleau Ghislain , Froguel Philippe , McCarthy Mark I. , Pritchard Jonathan K. 
Published: May 2016

AbstractDetection of recent natural selection is a challenging problem in population genetics, as standard methods generally integrate over long timescales. Here we introduce the Singleton Density Score (SDS), a powerful measure to infer very recent changes in allele frequencies from contemporary genome sequences. When applied to data from the UK10K Project, SDS reflects allele frequency changes in the ancestors of modern Britons during the past 2,000 years. We see strong signals of selection at lactase and HLA, and in favor of blond hair and blue eyes. Turning to signals of polygenic adaptation we find, remarkably, that recent selection for increased height has driven allele frequency shifts across most of the genome. Moreover, we report suggestive new evidence for polygenic shifts affecting many other complex traits. Our results suggest that polygenic adaptation has played a pervasive role in shaping genotypic and phenotypic variation in modern humans.
Cell-cycle coupled expression minimizes random fluctuations in gene product levels
Authors: Soltani Mohammad , Singh Abhyudai 
Published: May 2016

AbstractExpression of many genes varies as a cell transitions through different cell-cycle stages. How coupling between stochastic expression and cell cycle impacts cell-to-cell variability (noise) in the level of protein is not well understood. We analyze a model, where a stable protein is synthesized in random bursts, and the frequency with which bursts occur varies within the cell cycle. Formulas quantifying the extent of fluctuations in the protein copy number are derived and decomposed into components arising from the cell cycle and stochastic processes. The latter stochastic component represents contributions from bursty expression and errors incurred during partitioning of molecules between daughter cells. These formulas reveal an interesting trade-off: cell-cycle dependencies that amplify the noise contribution from bursty expression also attenuate the contribution from partitioning errors. We investigate existence of optimum strategies for coupling expression to the cell cycle that minimize the stochastic component. Intriguingly, results show that a zero production rate throughout the cell cycle, with expression only occurring just before cell division minimizes noise from bursty expression for a fixed mean protein level. In contrast, the optimal strategy in the case of partitioning errors is to make the protein just after cell division. We provide examples of regulatory proteins that are expressed only towards the end of cell cycle, and argue that such strategies enhance robustness of cell-cycle decisions to the intrinsic stochasticity of gene expression.