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Particuology 2014年第4期12卷 9-17页

作者： Jung Hoon Chae george Zheng Chen Department of Chemical and environmental engineering and Energy and Sustainability Research DivisionFaculty of EngineeringUniversity of NottinghamNottinghamNG7 2RDUK

A commercial product of carbon nano-particles, Cabot MONACH 1300 pigment black （CMPB）, was studied for basic structural information and electrochemical performance in neutral aqueous electrolytes, aiming at applications in supercapacitors. As confirmed by SeM and HRTeM, the CMPB had a hierarchical struc- ture, containing basic 10 nm nano-spheres which combined into ca. 50 nm agglomerates which further aggregated into larger particles of micrometres. The capacitance of this commercial material was found to increase with decreasing the size of hydrous cation （Li＋→Na＋ → K＋）, instead of the cation crystal radius （K＋→ Na＋→Li＋） when coupled with the same anion （cl-）. In electrolytes with the same cation concentration （K＋）, changing the anion from the larger dianion （SO42 ） to the smaller monoanion （cl-） also increased the capacitance at high potential scan rates （〉50 mV/s）. Increasing electrolyte concentration produced expected effect, including raising the electrode capacitance, but lowering the equivalent series resistance （eSR）, charge transfer resistance （CTR）, and the diffusion resistance. At higher temperatures, the CMPB exhibited slightly higher capacitance, which does not agree with the Gouy-Chapman theory on electric double layer （eDL）. A hypothesis is proposed to account for the capacitance increase with temperature as a result of the CMPB opening up some micro-pores for more ions to access in response to the temperature increase.

关键词： Carbon nano-particlesSupercapacitorNeutral aqueous electrolytesIonic propertieselectrochemistry

C-peptide as a key risk factor for non-alcoholic fatty liver disease in the United States population

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World Journal of Gastroenterology 2018年第32期24卷 3663-3670页

作者： Amporn Atsawarungruangkit Jirat Chenbhanich george Dickstein Department of Medicine MetroWest Medical CenterFraminghamMA 01702United States Department of Medicine Tufts University School of MedicineBostonMA 02111United States

AIM To determine whether fasting C-peptide is an independent predictor for non-alcoholic fatty liver disease(NAFLD) in United States population.MeTHODS Using the National Health and Nutrition examination Survey(NHANeS) 1988-1994, NAFLD participants aged 20 or greater without any other liver diseases were included in this study. excessive alcohol intake is defined as > 2 drinks per day for males and > 1 drink per day for females. C-peptide and 27 other factors known to be associated with NAFLD(e.g., age, gender, body mass index, waist circumference, race/ethnicity, liver chemistries, and other diabetes tests) were tested in both univariate and multivariate level using logistic regression with a P-value 0.05.ReSULTS Of 18825 participants aged ≥ 20, 3235 participants(n = 3235) met inclusion criteria. There were 23 factors associated with NAFLD by univariate analysis. 9 factors, ranked by the highest change in pseudo R2, were found to be significant predictors of NAFLD in multivariate model: waist circumference, fasting C-peptide, natural log of alanine aminotransferase(ALT), total protein, beingMexican American, natural log of glycated hemoglobin, triglyceride level, being non-Hispanic white, and ferritin level. CONCLUSION Together with waist circumference and ALT, fasting C-peptide is among three most important predictors of NAFLD in United States population in the NHANeS data set. Further study is needed to validate the clinical utility of fasting C-peptide in diagnosis or monitoring insulin resistance in NAFLD patients.

关键词： Insulin resistance Fatty liver Hepatosteatosis Metabolic syndrome C-peptide

New insights on molecular regulation of biofilm formation in plant-associated bacteria

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Journal of Integrative Plant Biology 2016年第4期58卷 362-372页

作者： Luisa F.Castiblanco george W.Sundin Department of Plant Soil and Microbial Sciences and Center for Microbial Pathogenesis Michigan State University

Biofilms are complex bacterial assemblages with a defined three-dimensional architecture, attached to solid surfaces, and surrounded by a self-produced matrix generally composed of exopolysaccharides, proteins, lipids and extracellular DNA. Biofilm formation has evolved as an adaptive strategy of bacteria to cope with harsh environmental conditions as well as to establish antagonistic or beneficial interactions with their host. Plant-associated bacteria attach and form biofilms on different tissues including leaves, stems,vasculature, seeds and roots. In this review, we examine the formation of biofilms from the plant-associated bacterial perspective and detail the recently-described mechanisms of genetic regulation used by these organisms to orchestrate biofilm formation on plant surfaces. In addition, we describe plant host signals that bacterial pathogens recognize to activate the transition from a planktonic lifestyle to multicellular behavior.

关键词： Cyclic-di-GMP erwinia amylovora small RNAs Xanthomonas campestris Xylella fastidiosa

Male courtship signal modality and female mate preference in the wolf spider Schizocosa ocreata: results of digital multimodal playback studies

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Current Zoology 2019年第6期65卷 705-711页

作者： elizabeth C.KOZAK george W.UeTZ Department of Biological Sciences University of CincinnatiCincinnatiOHP.0.Box 260006USA45221-0006

Females must be able to perceive and assess male signals,especially when they occur simultaneously with those of other males.Previous studies show female Schizocosa ocreata wolf spiders display receptivity to isolated visual or vibratory courtship signals,but increased receptivity to multimodal courtship.It is unknown whether this is true when females are presented with a choice between simultaneous multimodal and isolated unimodal male courtship.We used digital playback to present females with a choice simulating simultaneous male courtship in different sensory modes without variation in information content:1)isolated unimodal visual versus vibratory signals;2)multimodal versus vibratory signals;and 3)multimodal versus visual signals.When choosing between isolated unimodal signals(visual or vibratory),there were no significant differences in orientation latency and number of orientations,approaches or receptive displays directed to either signal.When given a choice between multimodal versus vibratory-only male courtship signals,females were more likely to orient to the multimodal stimulus,and directed significantly more orients,approaches and receptivity behaviors to the multimodal signal.When presented with a choice between multimodal and visual-only signals,there were significantly more orients and approaches to the multimodal signal,but no significant difference in female receptivity.Results suggest that signal modes are redundant and equivalent in terms of qualitative responses,but when combined,multimodal signals quantitatively enhance detection and/or reception.This study confirms the value of testing preference behavior using a choice paradigm,as female preferences may depend on the context(e.g.,environmental context and social context)in which they are presented with male signals.

关键词： mate choice multimodal communication Schizocosa signaling wolf spider

The antibiotic resistome： gene flow in environments, animals and human beings

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Frontiers of Medicine 2017年第2期11卷 161-168页

作者： Yongfei Hu george F. Gao Baoli Zhu CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China Beijing Key Laboratory of Microbial Drug Resistance and Resistome Beijing 100101 China Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases The First Affiliated Hospital Zhejiang University Hangzhou 310006 China Research Network of lmmunity and Health (RNIH) Beijing Institutes of Life Science Chinese Academy of Sciences Beijing 100101 China Office of Director-General Chinese Center for Disease Control and Prevention (China CDC) Beijing 102206 China

The antibiotic resistance is natural in bacteria and predates the human use of antibiotics. Numerous antibiotic resistance genes （ARGs） have been discovered to confer resistance to a wide range of antibiotics. The ARGs in natural environments are highly integrated and tightly regulated in specific bacterial metabolic networks. However, the antibiotic selection pressure conferred by the use of antibiotics in both human medicine and agriculture practice leads to a significant increase of antibiotic resistance and a steady accumulation of ARGs in bacteria. In this review, we summarized, with an emphasis on an ecological point of view, the important research progress regarding the collective ARGs （antibiotic resistome） in bacterial communities of natural environments, human and animals, i.e., in the one health settings. We propose that the resistance gene flow in nature is ＂from the natural environments＂ and ＂to the natural environments＂; human and animals, as intermediate recipients and disseminators, contribute greatly to such a resistance gene ＂circulation.＂

关键词： antibiotic resistance resistome microbiome gene flow

Asymptotic Properties of a Modified Semi-Parametric MLe in Linear Regression with Right-Censored Data

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Acta Mathematica Sinica,english Series 2002年第2期18卷 405-416页

作者： WONG george Y.C. Strang Cancer Prevention Center.428 e 72nd Street.New York.NY 10021.USA

Consider a linear regression model Y=β'X+e.where Y may be right censored and the cdf F+o of e is unknown.We show that a modified semi-parametric MLe.denoted by .is strongly consistent under certain regularity conditions.Moreover.if F_o is discontinuous,then P(≠βi.o.)=0, which means that P(=βif the sample size is large)=1.The latter property has not been reported for the existing estimators.By contrast,most estimators,such as the Buckley-James estimator and M-estimators .satisfy that P(≠βi.o.)=1.

关键词： Consistency Super-efficiency Semi-parametric MLe

evidence for further charmonium vector resonances

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Chinese Physics C 2011年第4期35卷 319-324页

作者： eef van Beveren george Rupp Centro de Física Computacional Departamento de Física Universidade de Coimbra Centro de Física das Interaccoes Fundamentais Instituto Superior Tèecnico Universidade Tèecnica de Lisboa edifício Ciêencia

We discuss the shape of threshold signals in production cross sections of the reaction e＋e- → D＊ Dˉ＊, at the opening of the Ds＊ Dˉs＊ and Λc＋ Λ＋c channels. Furthermore, evidence for the ψ（3D）, ψ（5S）, ψ（4D）, ψ（6S）, ψ（5D）, ψ（7S）, ψ（6D）, and ψ（8S） new charmonium vector resonances is presented, on the basis of data recently published by the BABAR Collaboration. Central masses and resonance widths are estimated. Confirmation of these resonances would be a huge step in lifting the precision level of hadron spectroscopy towards that of atomic spectroscopy, with far-reaching consequences for theory.

关键词： heavy quarkonia hadron production in electron-positron annihilation

Analysis of equilibrium, kinetic, and thermodynamic parameters for biosorption of fluoride from water onto coconut(Cocos nucifera Linn.)root developed adsorbent

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Chinese Journal of Chemical engineering 2019年第1期27卷 92-99页

作者： Aju Mathew george Ajay R.Tembhurkar Civil engineering Department Visvesvaraya National Institute of Technology

Drinking water with higher fluoride levels results in serious irremediable health problems that have attained a startle all over the world.Researches focused towards deflouridation through the application of biosorbents prepared from various plants are finding greater scope and significance.Present research is done on Cocos nucifera Linn.(coconut tree) one of the very commonly available plants throughout Kerala and around the globe.An adsorbent developed from the root portion of C.nucifera Linn.is used in the present study.equilibrium study revealed that the fluoride uptake capacity is quite significant and linearly increases with initial adsorbate concentration.The adsorption data is analyzed for Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models at varying initial adsorbate concentrations(2–25 mg·L^(-1)).It is found that the adsorption of fluoride onto C.nucifera Linn.root adsorbent follows Langmuir isotherm.Langmuir isotherm constants "a" and "b" obtained are 2.037 mg·g^(-1) and 0.823 L·mg^(-1) at an adsorbent dose of 8 g·L^(-1) and temperature(26 ± 1) ℃.The mean free sorption energy, e obtained, is 9.13 kJ ·mol^(-1) which points out that the adsorption of fluoride onto C.nucifera Linn.root adsorbent is by chemisorption mechanism.The kinetic study also supports chemisorption with adsorption data fitting well with a pseudo-second-order kinetic model with an estimated rate constant K_2 of 0.2935 g·mg^(-1) min at an equilibrium contact time of 90 min.The thermodynamic study indicated the spontaneous and endothermic nature(ΔH =12.728 kJ·mol^(-1)) of fluoride adsorption onto the C.nucifera Linn.root adsorbent.Scanning electron Microscopy(SeM), BeT, FTIR, and eDX methods were used to analyze the surface morphology of adsorbent before and after fluoride adsorption process.experiments on deflouridation using C.nucifera Linn.root adsorbent application on fluoride contaminated ground water samples from fields showed encouraging results.

关键词： Fluoride Biosorption equilibrium Kinetics Thermodynamics Application

Genetic assessment of inbred chicken lines indicates genomic signatures of resistance to Marek's disease

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Journal of Animal Science and Biotechnology 2018年第4期9卷 803-812页

作者： Lingyang Xu Yanghua He Yi Ding george e.Liu Huanmin Zhang Hans H.Cheng Robert L.Taylor Jr. Jiuzhou Song Department of Animal & Avian Sciences University of Maryland Animal Genomics and Improvement Laboratory U.S. Department of Agriculture-Agricultural Research Services Laboratory of Molecular Biology and Bovine Breeding Institute of Animal Science Chinese Academy of Agricultural Sciences United States Department of Agriculture-Agriculture Research Service (ARS) Avian Disease and Oncology Laboratory Animal and Nutritional Sciences Davis College of Agriculture West Virginia University

Background: Marek's disease(MD) is a highly contagious pathogenic and oncogenic disease primarily affecting chickens. However, the mechanisms of genetic resistance for MD are complex and not fully understood. MD-resistant line 6_3 and MD-susceptible line 7_2 are two highly inbred progenitor lines of White Leghorn. Recombinant Congenic Strains(RCS) were developed from these two lines, which show varied susceptibility to MD.Results: We investigated genetic structure and genomic signatures across the genome, including the line 6_3 and line7_2, six RCSs, and two reciprocally crossed flocks between the lines 6_3 and 7_2(F1 6_3× 7_2 and F1 7_2× 6_3) using Affymetrix~? Axiom~? HD 600 K genotyping array. We observed 18 chickens from RCS lines were specifically clustered into resistance sub-groups distributed around line 6_3. Additionally, homozygosity analysis was employed to explore potential genetic components related to MD resistance, while runs of homozygosity(ROH) are regions of the genome where the identical haplotypes are inherited from each parent. We found several genes including SIK, SOX1, LIG4, SIK1 and TNFSF13B were contained in ROH region identified in resistant group(line 6_3 and RCS), and these genes have been reported that are contribute to immunology and survival. Based on F_(ST) based population differential analysis, we also identified important genes related to cell death and anti-apoptosis, including AKT1, API5, CDH13, CFDP and USP15,which could be involved in divergent selection during inbreeding process.Conclusions: Our findings offer valuable insights for understanding the genetic mechanism of resistance to MD and the identified genes could be considered as candidate biomarkers in further evaluation.

关键词： Genetic structure Genomic signature Homozygosity Marek’s disease Recombinant Congenic Strains(RCS)

Should antibiotics be administered before arthroscopic knee surgery? A systematic review of the literature

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World Journal of Orthopedics 2018年第11期9卷 262-270页

作者： John Carney Nathanael Heckmann erik N Mayer Ram K Alluri Carleton Thomas Vangsness george F Hatch Ⅲ Alexander e Weber Department of Orthopaedic Surgery University of Southern California

AIM To explore the current evidence surrounding the administration of prophylactic antibiotics for arthroscopic knee surgery. MeTHODS Databases were searched from inception through May of 2018 for studies examining prophylactic antibiotic use and efficacy in knee arthroscopy. Studies with patient data were further assessed for types of arthroscopic procedures performed,number of patients in the study,use of antibiotics,and outcomes with the intention of performing a pooled analysis. Data pertaining to "deep tissue infection" or "septic arthritis" were included in our analysis. Reported data on superficial infection were not included in our data analysis. For the pooled analysis,a relative risk ratio was calculated and χ~2 tests were used to assess for statistical significance between rates of infection amongst the various patient groups. Post hoc power analyses were performed to compute the statistical power obtained from our sample sizes. Number needed to treat analyses were performed for statistically significant differences by dividing 1 by the difference between the infection rates of the antibiotic and no antibiotic groups. An alpha value of 0.05 was used for our analysis. Study heterogeneity was assessed by Cochrane's Q test as well as calculation of the I^2 value.ReSULTS A total of 49682 patients who underwent knee ar-throscopy for a diverse set of procedures across 19 studies met inclusion critera for pooled analysis. For those not undergoing graft procedures,there were 27 cases of post-operative septic arthritis in 34487 patients(0.08%) who received prophylactic antibiotics and 16 cases in 10911(0.15%) who received none [risk ratio(RR) = 0.53,95% confidence interval(CI): 0.29-0.99,P = 0.05]. A sub-group analysis in which bony procedures were excluded was performed which found no significant difference in infection rates between patients that received prophylactic antibiotics and patients that did not(P > 0.05). All anterior cruciate ligament reconstruction studies used prophylactic antibiotics,but two st

关键词： Knee arthroscopy Antibiotics Systematic review Vancomycin Anterior cruciate ligament