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Insect Science 2019年第3期26卷 499-509页

作者： Xu-Jiang He Wu-Jun Jiang Mi Zhou andrew b. barron Zhi-Jiang Zeng Honeybee Research Institute Jiangxi Agricultural University Nanchang China biomarker Technologies Co. Ltd. Beijing China 2Department of biological Sciences Macquarie University North Ryde NSW Australia

Honeybees (Apis mellifera) have haplodiploid sex determination: males develop from unfertilized eggs and females develop from fertilized ones. The differences in larval food also determine the development of females. Here we compared the total somatic gene expression profiles of 2-day and 4-day-old drone, queen and worker larvae by RNASeq. The results from a co-expression network analysis on all expressed genes showed that 2-day-old drone and worker larvae were closer in gene expression profiles than 2-day-old queen larvae. This indicated that for young larvae (2-day-old) environmental factors such as larval diet have a greater effect on gene expression profiles than ploidy or sex determination. Drones had the most distinct gene expression profiles at the 4-day larval stage, suggesting that haploidy, or sex dramatically affects the gene expression of honeybee larvae. Drone larvae showed fewer differences in gene expression profiles at the 2-day and 4-day time points than the worker and queen larval comparisons (598 against 1190 and 1181), suggesting a different pattern of gene expression regulation during the larval development of haploid males compared to diploid females. This study indicates that early in development the queen caste has the most distinct gene expression profile, perhaps reflecting the very rapid growth and morphological specialization of this caste compared to workers and drones. Later in development the haploid male drones have the most distinct gene expression profile, perhaps reflecting the influence of ploidy or sex determination on gene expression.

关键词： caste differentiation envir on mental factors gene expression haploid and diploid honeybees larval development

Demonstration of Covalent Sidewall Functionalization of Single Wall Carbon Nanotubes by NMR Spectroscopy:Side Chain Length Dependence on the Observation of the Sidewall sp^(3)Carbons

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Nano Research 2008年第1期1卷 72-88页

作者： Liling Zeng Lawrence b.Alemany Christopher L.Edwards andrew R.barron Richard E.Smalley Institute for Nanoscale Science and Technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(SWNTs)prepared via the reaction of an amino acid,NH2(CH2)nCO2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-SWNTs)have been characterized by MAS 13C NMR *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMR data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized SWNTs were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-SWNT(C1)+1-dodecanol(C_(12))=DOD-GLY-SWNT(1),AHA-SWNT(C_(5))+1-octanol(C_(8))=OCT-AHA-SWNT(2),and AUDA-SWNT(C_(10))+1-propanol(C_(3))=PRO-AUDA-SWNT(3).The 13C NMR shift for the sp3 nitrogen-substituted carbon atoms of the SWNT sidewall is observed atδ≈75 *** the length of SWNT sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized SWNTs than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-SWNT with 1,3-propanediol:PPD-AUDA-SWNT(4).

关键词： Single walled carbon nanotube(SWNT) nuclear magnetic resonance(NMR) esterification amino acid functionalization

Solvent-free microwave-assisted synthesis of tenorite nanoparticle-decorated multi-walled carbon nanotubes

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Journal of Materials Science & Technology 2019年第6期35卷 1121-1127页

作者： Jennifer A. Rudd Cathren E. Gowenlock Virginia Gomez Ewa Kazimierska Abdullah M. Al-Enizi Enrico Andreoli andrew R. barron Energy Safety Research Institute Swansea University Bay Campus Swansea SA1 8EN UK Chemistry Department College of Sciences KingSaud University Riyadh Saudi Arabia Department of Chemistry Rice University Houston Texas 77005 USA Department of Materials Science and Nanoengineering Rice University Houston Texas 77005 USA

Copper-decorated carbon nanotubes(CNTs) have important applications as precursors for ultraconductive copper wires. Tenorite-decorated CNTs(CuO-CNTs) are ideal candidates and are currently developed using laborious processes. For this reason, we have developed a facile and scalable method for the synthesis of CuO-CNTs from copper acetate. It was found that the optimal loading of copper acetate onto the CNTs was 23.1 wt% and that three 1-minute microwave treatments were sufficient for the decomposition of copper acetate to copper oxide. The loading of copper oxide onto the nanotubes was confirmed using X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy and thermogravimetric analysis. The materials were characterised using X-ray diffraction and scanning electron microscopy.

关键词： Microwave-assisted synthesis Multi-walled carbon nanotubes Tenorite Nanoparticle

Numerical Solution of Partial Differential Equations in Arbitrary Shaped Domains Using Cartesian Cut-Stencil Finite Difference *** II:Higher-Order Schemes

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Numerical Mathematics(Theory,Methods and Applications) 2022年第3期15卷 819-850页

作者： M.Esmaeilzadeh R.M.barron Department of Mechanical Automotive&Materials EngineeringUniversity of WindsorWindsorOntarioN9B 3P4Canada Department of Mathematics&Statistics University of WindsorWindsorOntarioN9B 3P4Canada Department of Mechanical Engineering South Tehran BranchIslamic Azad UniversityTehranP.C:***Iran

Compact higher-order(HO)schemes for a new finite difference method,referred to as the Cartesian cut-stencil FD method,for the numerical solution of the convection-diffusion equation in complex shaped domains have been addressed in this *** Cartesian cut-stencil FD method,which employs 1-D quadratic transformation functions to map a non-uniform(uncut or cut)physical stencil to a uniform computational stencil,can be combined with compact HO Pad´e-Hermitian formulations to produce HO cut-stencil *** modified partial differential equation technique is used to develop formulas for the local truncation error for the cut-stencil HO *** effect of various HO approximations for Neumann boundary conditions on the solution accuracy and global order of convergence are *** numerical results for second-order and compact HO formulations of the Cartesian cut-stencil FD method have been compared for test problems using the method of manufactured solutions.

关键词： Cartesian cut-stencil finite difference method compact higher-order formulation irregular domain Neumann boundary conditions local truncation error

Clinical, cellular, microscopic, and ultrastructural studies of a case of fibrogenesis imperfecta ossium

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bone Research 2017年第2期5卷 123-136页

作者： Melissa L barron Mark S Rybchyn Sutharshani Ramesh Rebecca S Mason S Fiona bonar Paul Stalley Sundeep Khosla bernie Hudson Christopher Arthur Edward Kim Roderick J Clifton-bligh Phillip b Clifton-bligh Department of Physiology School of Medical Sciences Bosch Institute University of Sydney Sydney 2006 New South Wales Australia Douglas HanlyMoir Pathology Macquarie Park 2113 New South Wales Australia Department of Orthopaedics Royal Prince Alfred HospitalCamperdown 2050 New South Wales Australia Department of Endocrinology Mayo Clinic Rochester 55905 MN USA Department of Microbiology Royal North Shore Hospital St Leonards 2065 New South Wales Australia Department ofMicrobiology Royal North Shore Hospital St Leonards 2065 New South Wales Australia Department of Haematology Royal North Shore Hospital St Leonards 2065 New South Wales Australia Department of Endocrinology Royal North Shore Hospital St Leonards 2065 New SouthWales Australia and Faculty of Medicine University of Sydney Sydney 2006 New South Wales Australia

Fibrogenesis imperfecta ossium is a rare disorder of bone usually characterized by marked osteopenia and associated with variable osteoporosis and osteosclerosis, changing over time. Histological examination shows that newly formed collagen is abnormal, lacking birefringence when examined by polarized light. The case presented demonstrates these features and, in addition, a previously undocumented finding of a persistent marked reduction of the serum C3 and C4. Osteoblasts established in culture from a bone biopsy showed abnormal morphology on electron microscopy and increased proliferation when cultured with benzoylbenzoyl-ATP and 1,25-dihydroxyvitamin D, contrasting with findings in normal osteoblasts in culture. A gene microarray study showed marked upregulation of the messenger RNA(mRNA) for G-protein-coupled receptor 128(GPR 128), an orphan receptor of unknown function and also of osteoprotegerin in the patient's osteoblasts in culture. When normal osteoblasts were cultured with the patient's serum, there was marked upregulation of the mRNA for aquaporin 1. A single pathogenetic factor to account for the features of this disorder has not been defined, but the unique findings described here may facilitate more definitive investigation of the abnormal bone cell function.

关键词： ultrastructural cellular Clinical

Designing healthy communities： A walkability analysis of LEED-ND

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Frontiers of Architectural Research 2016年第4期5卷 433-452页

作者： Adriana A. Zuniga-Teran barron J. Orr Randy H. Gimblett Nader V. Chalfoun Scott b. Going David P. Guertin Stuart E. Marsh Udall Center for Studies in Public Policy University of Arizona Tucson AZ 85719 USA

Prevailing city design in many countries has created sedentary societies that depend on automobile use. Consequently, architects, urban designers, and land planners have developed new urban design theories, which have been incorporated into the Leadership in Energy and Environmental Design for Neighborhood Development （LEED-ND） certification system. The LEED- ND includes design elements that improve human well-being by facilitating walking and biking, a concept known as walkability. Despite these positive developments, relevant research findings from other fields of study have not been fully integrated into the LEED-ND. According to Zuniga-Teran （2015）, relevant walkability research findings from multiple disciplines were organized into a walkability framework （WF） that organizes design elements related to physical activity into nine categories, namely, connectivity, land use, density, traffic safety, surveil- lance, parking, experience, greenspace, and community. In this study, we analyze walkability in the LEED-ND through the lens of the nine WF categories. Through quantitative and qualitative analyses, we identify gaps and strengths in the LEED-ND and propose potential enhancements to this certification system that reflects what is known about enhancing walkability more comprehensively through neighborhood design analysis. This work seeks to facilitate the translation of research into practice, which can ultimately lead to more active and healthier societies.

关键词： Watkabitity LEED-ND Physical activity Urban design Well-being built environment

Effect of inductively coupled plasma surface treatment on silica gel and mesoporous MCM-41 particles

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Plasma Science and Technology 2018年第6期20卷 104-113页

作者： J A JUAREZ-MORENO U CHACON-ARGAEZ J barron-ZAMbRANO C CARRERA-FIGUEIRAS P QUINTANA-OWEN W TALAVERA-PECH Y PEREZ-PADILLA A AVILA-ORTEGA facultad de ingeniería química-uady periférico norte kilómetro 33.5col.chuburna de hidalgo inn C.P. 97203 Mérida Yucatan México centro de investigación y de estudios avanzados del ipn-unidad mérida km.6 antigua carretera a progreso apdo. Postal 73 Cordemex 97310 Méfida Yucatán México

Silica gel and MCM-41 synthesized mesoporous materials were treated with either oxygen（O_2）,hexamethyldisiloxane（HMDSO） and organic vapors like ethanol（Et OH）,and acrylonitrile（AN）inductive *** radiofrequency power for the modification was fixed to 120 W and30 min,assuring a high degree of organic ionization energy in the *** surface properties were studied by infrared spectroscopy（FTIR）,scanning electron microscopy,x-ray photoelectron spectroscopy and dynamic light scattering technique was used for characterizing size *** the silica and MCM-41 particles were modified by AN and HMDSO plasma gases,the surface morphology of the particles was changed,presenting another color,size or *** contrast,the treatments of oxygen and Et OH did not affect the surface morphology of both particles,but increased the oxygen content at the surface bigger than the AN and HMDSO plasma *** this study,we investigated the influence of different plasma treatments on changes in morphology and the chemical composition of the modified particles which render them a possible new adsorbent for utilization in sorptive extraction techniques for polar compounds.

关键词： silica MCM-41 nanoparticles plasma treatment

Designing healthy communities： Testing the walkability model

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Frontiers of Architectural Research 2017年第1期6卷 63-73页

作者： Adriana A. Zuniga-Teran barron J. Orr Randy H. Gimblett Nader V. Chalfoun Stuart E. Marsh David P. Guertin Scott b. Going Udall Center for Studies in Public Policy University of Arizona Tucson AZ 85719 USA

Research from multiple domains has provided insights into how neighborhood design can be improved to have a more favorable effect on physical activity, a concept known as walkability. The relevant research findings/hypotheses have been integrated into a Walkability Framework, which organizes the design elements into nine walkability categories. The purpose of this study was to test whether this conceptual framework can be used as a model to measure the interactions between the built environment and physical activity. We explored correlations between the walkability categories and physical activity reported through a survey of residents of Tucson, Arizona （n=486）. The results include significant correlations between the walkability categories and physical activity as well as between the walkabi[ity categories and the two motivations for walking （recreation and transportation）. To our knowledge, this is the first study that reports links between wa[kability and walking for recreation. Additionally, the use of the Walkability Framework allowed us to identify the walkability categories most strongly correlated with the two motivations for walking. The results of this study support the use of the Walkability Framework as a model to measure the built environment in relation to its ability to promote physical activity.

关键词： Watkability Physical activity buitt environment LEED-ND Neighborhood design

Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes

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Current Zoology 2014年第6期60卷 804-815页

作者： Hubert SCHWAbL Willow R. LINDSAY Douglas G. barron Michael S. WEbSTER School of biological Sciences and Center for Reproductive biology Washington State University Pullman WA 99164-4236 USA Department of Department of biological and Environmental Sciences Goteborg University Box 463405 30 Goteborg Sweden Department of Psychology University of South Florida Tampa FL 33620-7200 USA Department of Neurobiology and behavior and Comell Laboratory for Ornithology Comell University Ithaca NY 14850 USA

While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.

关键词： Androgen Estrogen Glucocorticoid Mate choice Promiscuity Alternative phenotypes