检索结果-南通市图书馆

Nonlinearly Coupled KdV Equations Describing the Interaction of Equatorial and Midlatitude Rossby Waves

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2009年第5期30卷 483-504页

作者： joseph A. BIELLO Department of Mathematics University of California at Davis

Amplitude equations governing the nonlinear resonant interaction of equatorial baroclinic and barotropic Rossby waves were derived by Majda and Biello and used as a model for long range interactions （teleconnections） between the tropical and midlatitude troposphere. An overview of that derivation is nonlinear wave theory, but not in atmospheric presented and geared to readers versed in sciences. In the course of the derivation, two other sets of asymptotic equations are presented： the long equatorial wave equations and the weakly nonlinear, long equatorial wave equations. A linear transformation recasts the amplitude equations as nonlinear and linearly coupled KdV equations governing the amplitude of two types of modes, each of which consists of a coupled tropical/midlatitude flow. In the limit of Rossby waves with equal dispersion, the transformed amplitude equations become two KdV equations coupled only through nonlinear fluxes. Four numerical integrations are presented which show （i） the interaction of two solitons, one from either mode, （ii） and （iii） the interaction of a soliton in the presence of different mean wind shears, and （iv） the interaction of two solitons mediated by the presence of a mean wind shear.

关键词： Coupled KdV equations Equatorial Rossby waves Solitary waves Atmospheric teleconnections

Analgesic effects of JCM-16021 on neonatal maternal separation-induced visceral pain in rats

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2010年第7期16卷 837-845页

作者： joseph JY Sung Faculty of Medicine The Chinese University of Hong Kong

AIM:To investigate the pharmacological effect of JCM-16021,a Chinese herbal formula,and its underlying ***:JCM-16021 is composed of seven herbal plant *** raw materials of the formula were examined according to the quality control criteria listed in the Chinese Pharmacopeia(2005).In a neonatal maternal separation(NMS)model,male SpragueDawley rats were submitted to daily maternal separation from postnatal day 2 to day 14,or no specific handling(NH).Starting from postnatal day 60,rats were administered JCM-16021(2,4,8 g/kg per day)orally twice a day for 28 *** threshold pressure and electromyographic activities of external oblique muscles in response to colorectal distention recorded with a Power Lab System(AD Instruments International),were tested as pain *** in serotonin(5-HT)and 5-hydroxyindoleacetic acid(5-HIAA)concentrations in the colon of rats were analyzed;the enterochromaffin cell numbers and serotonin transporter in the colon of rats were also evaluated with an immunohistochemistry ***:NMS treatment significantly reduced pain threshold pressure(37.4±1.4 mmHg),as compared to that of NH rats(57.7±1.9 mmHg,P<0.05).After JCM-16021 treatment,the pain threshold pressure significantly increased when compared to that before treatment(34.2±0.9 mmHg vs 52.8±2.3 mmHg in the high dose group,40.2±1.6 mmHg vs 46.5±1.3 mmHg in the middle dose group,and 39.3±0.7 mmHg vs 46.5±1.6 mmHg in the low dose group,P<0.05).Also JCM-16021 significantly and dose-dependently decreased electromyographic activity to the graded colorectal distension(CRD),(the meanΔAUC values were:0.17±0.03,0.53±0.15,1.06±0.18,1.22±0.24 in the high dose group;0.23±0.04,0.68±0.17,1.27 ±0.26,1.8±0.3 in the middle dose group;and 0.29 ±0.06,0.8±0.16,1.53±0.24,2.1±0.21 in the low dose group for the pressures 20,40,60,80 mmHg),as compared to the NMS vehicle *** meanΔAUC values were:0.57±0.12,1.33±0.18,2.57±0.37,3.08±0.37 for the pressures 20,40,60,80 mmHg(P

关键词： Analgesia effect Neonatal maternal separation Visceral hyperalgesia Herbal medicine Serotonin pathway

Keeping an ear out:size relationship of the tympanic bullae and pinnae in bandicoots and bilbies(Marsupialia:Peramelemorphia)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2022年第3期68卷 251-264页

作者： Melissa C.TAYLOR Kenny J.TRAVOUILLON Margaret E.ANDREW Patricia A.FLEMING Natalie M.warburton Terrestrial Ecosystem Science and Sustainability Harry Butler InstituteMurdoch University90 South StMurdochWA 6150Australia Collections and Research Western Australian MuseumWelshpoolWA 6106Australia

Bandicoots and bilbies(Order Peramelemorphia)occupy a broad range of habitats across Australia and New Guinea,from open,arid deserts to dense *** once diverse group has been particularly vulnerable to habitat loss and introduced eutherian predators,and numerous species extinctions and range retractions have *** reasons for this loss requires greater understanding of their *** of the pinnae and tympanic bullae varies markedly among *** hearing is important for both predator avoidance and prey location,the variability in ear morphology could reflect specialization and adaptation to specific environments,and therefore be of conservation *** measured 798 museum specimens representing 29 species of *** for phylogenetic relatedness and head length,pinna surface area was weakly negatively correlated with average precipitation(rainfall being our surrogate measure of vegetation productivity/complexity),and there were no environmental correlates with effective diameter(pinna width).Controlling for phylogenetic relatedness and skull length,tympanic bulla volume was negatively correlated with *** that inhabited drier habitats,which would be open and allow sound to carry further with less obstruction,had relatively larger pinnae and tympanic *** contrast,species from higher rainfall habitats,where sounds would be attenuated and diffused by dense vegetation,had the smallest pinnae and bullae,suggesting that low-frequency hearing is not as important in these *** with temperature did not reach statistical *** findings highlight linkages between hearing traits and habitat that can inform conservation and management strategies for threatened species.

关键词： external ear hearing ecology marsupial middle ear sound perception

Nonlinear vibrations of electroelastic shells with relatively large shear deformations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 660-670页

作者： joseph A. Turner Department of Engineering Mechanics University of Nebraska Lincoln NE 68588-0526 U.S.A.

A set of two-dimensional nonlinear equations for thin electroelastic shells in vibrations with moderately large thickness-shear deformations are obtained from the variational formulation of the three-dimensional equations of nonlinear electroelasticity by expanding the mechanical displacement vector and the electric potential into power series in the shell thickness coordinate and retaining lower order terms. As an example,the equations are used to study nonlinear thickness-shear vibrations of a circular cylindrical shell driven by an electric voltage. Nonlinear amplitude-frequency behavior of electric current near strong resonance is obtained.

关键词： piezoelectricity,shell.

The Agricultural-Industrial Partnership for Eliminating Micronutrient Malnutrition: The Investment Bargain of the Decade

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2001年第1期14卷 104-123页

作者： joseph MICHAEL HUNT Senior Health and Nutrition Economist Asian Development Bank Manila Philippines

The limitations of conventional approaches to eliminating micronutrient deficiencies drives the search for a sustainable paradigm. This manuscript argues that the public and private sectors must embark on modernization of the Asian food industry and reorientation of the international agricultural research complex so that nutritionally enriched essential foods will be affordable and accessible to the poor. It is recommended that this partnership take special care of the needs of Asian children. The costs of chronic undernutrition, availability of cost effective strategies, and benefits of sustained nutrition improvement to individuals, families and nations are reviewed. The roles of food fortification, plant breeding and biotechnology, both actual and imminent, are described. The paper concludes that a recast Green Revolution directed to dietary quality may be the key to enhancing the learning and earning capacity of young Asians of the new millenium. “No other technology offers as large an opportunity to improve lives\{…\}at such a low cost and in such a short time\{…\}” World Bank [1] .

关键词： Agriculture Child Welfare Industry Micronutrients Nutrition Policy Biotechnology Child Food Industry Food Fortified Humans Interprofessional Relations Nutrition Disorders Policy Making

Breaking wheat yield barriers requires integrated efforts in developing countries

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2015年第8期14卷 1447-1474页

作者： Saeed Rauf Maria Zaharieva Marilyn L warburton ZHANG Ping-zhi Abdullah M AL-Sadi Farghama Khalil Marcin Kozak Sultan A Tariq Department of Plant Breeding & Genetics University College of Agriculture University of Sargodha National Agricultural University La Molina (UNALM) USDA ARS Corn Host Plant Resistance Research Unit Crop Research Institute Anhui Academy of Agricultural Sciences Department of Crop Science College of Agricultural and Marine Sciences Sultan Qaboos University Department of Botany Warsaw University of Life Sciences-SSGW Social Sciences Research Institute National Agriculture Research Council

Most yield progress obtained through the so called ＂Green Revolution＂, particularly in the irrigated areas of Asia, has reached a limit, and major resistance genes are quickly overcome by the appearance of new strains of disease causing *** plant stresses due to a changing environment are difficult to breed for as quickly as the changes *** is consequently a continual need for new research programs and breeding strategies aimed at improving yield potential, abiotic stress tolerance and resistance to new, major pests and *** advances in plant breeding encompass novel methods of expanding genetic variability and selecting for recombinants, including the development of synthetic hexaploid, hybrid and transgenic *** addition, the use of molecular approaches such as quantitative trait locus（QTL） and association mapping may increase the possibility of directly selecting positive chromosomal regions linked with natural variation for grain yield and stress *** present article reviews the potential contribution of these new approaches and tools to the improvement of wheat yield in farmer＇s fields, with a special emphasis on the Asian countries, which are major wheat producers, and contain the highest concentration of resource-poor wheat farmers.

关键词： genetic diversity heterosis hybrid wheat synthetic hexaploid wheat yield potential

Adaptive hearing in the vocal plainfin midshipman fish:getting in tune for the breeding season and implications for acoustic communication

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2009年第1期4卷 33-42页

作者： joseph A.SISNEROS Department of Psychology the Department of Biology and the Virginia Merrill Bloedel Hearing Research CenterUniversity of WashingtonSeattleUSA

The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has become a good model for investigating the neural and endocrine mechanisms of vocal-acoustic ***-tively active female plainfin midshipman fish use their auditory sense to detect and locate“singing”males,which produce a multiharmonic advertisement call to attract females for *** seasonal onset of male adver-tisement calling in the midshipman fish coincides with an increase in the range of frequency sensitivity of the female’s inner ear saccule,the main organ of hearing,thus leading to enhanced encoding of the dominant frequency components of male advertisement ***-reproductive females treated with either testosterone or 17β-estradiol exhibit a dramatic increase in the inner ear’s frequency sensitivity that mimics the reproductive fe-male’s auditory phenotype and leads to an increased detection of the male’s advertisement *** novel form of auditory plasticity provides an adaptable mechanism that enhances coupling between sender and receiver in vocal *** review focuses on recent evidence for seasonal reproductive-state and steroid-dependent plasticity of auditory frequency sensitivity in the peripheral auditory system of the midshipman *** potential steroid-dependent mechanism(s)that lead to this novel form of auditory and behavioral plasticity are also dis-cussed.

关键词： auditory plasticity hair cells saccule sex steroids tuning.

Building Momentum to Realign Incentives to Support Open Science

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Data Intelligence 2021年第1期3卷 71-78页

作者： Heather joseph SPARC(Scholarly Publishing and Academic Resources Coalition) Washington DC 20036USA

The COVID-19 pandemic highlights the urgent need to strengthen global scientific collaboration,and to ensure the fundamental right to universal access to scientific progress and its *** Science(OS)is central to achieving these *** aims to make science accessible,transparent,and effective by providing barrier-free access to scientific publications,data,and infrastructures,along with open software,Open Educational Resources,and open *** also promotes public trust in science at a time when it has never been more important to do *** the past decade,momentum towards the widespread adoption of OS practices has been primarily driven by declarations(e.g.,DORA,the Leiden Manifesto).These serve an important role,but for OS to truly take root,researchers also must be fully incentivized and rewarded for its *** requires research funders and academic leaders to take the lead in collaborating,with researchers in designing,and implementing new incentive structures,and to actively work to socialize these throughout the research *** US National Academies of Science,Engineering,and Medicine(NASEM)Roundtable on Aligning Research Incentives for OS is one such *** paper examines the strategy behind convening the Roundtable,its current participant makeup,focus,and *** also explores how this approach might be expanded and adapted throughout the global OS community.

关键词： Research assessment Incentives Open Science NASEM Roundtable

Robust Control of a Bevel-Tip Needle for Medical Interventional Procedures

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 244-256页

作者： Surender Hans Felix Orlando Maria joseph Department of Electrical Engineering Indian Institute of Technology RoorkeeRoorkeeUttarakhand 247667India

In minimally invasive surgery, one of the main objectives is to ensure safety and target reaching accuracy during needle steering inside the target organ. In this research work, the needle steering approach is determined using a robust control algorithm namely the integral sliding mode control(ISMC) strategy to eliminate the chattering problem associated with the general clinical scenario. In general, the discontinuity component of feedback control input is not appropriate for the needle steering methodology due to the practical limitations of the driving actuators. Thus in ISMC, we have incorporated the replacement of the discontinuous component using a super twisting control(STC)input due to its unique features of chattering elimination and disturbance observation characteristics. In our study, the kinematic model of an asymmetric flexible bevel-tip needle in a soft-tissue phantom is used to evaluate stability analysis. A comparative study based on the analysis of chattering elimination is executed to determine the performance of the proposed control strategy in real-time needle steering with conventional sliding mode control using vision feedback through simulation and experimental results. This validates the efficacy of the proposed control strategy for clinical needle steering.

关键词： Minimal invasive surgery needle steering nonholonomic system robust control sliding mode control