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A Model System of Development Regulated by the Long-distance Transport of mRNA

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journal of Integrative Plant Biology 2010年第1期52卷 40-52页

作者： david j. Hannapel Plant Biology Major 253 Horticulture Hall Iowa State University

BELl-like transcription factors are ubiquitous in plants and interact with KNOTTEDI-types to regulate numerous developmental processes. In potato, the RNA of several BELl-like transcription factors has been identified in phloem cells. One of these, StBEL5, and its Knox protein partner regulate tuber formation by targeting genes that control growth. RNA detection methods and grafting experiments demonstrated that StBEL5 transcripts move across a graft union to localize in stolon tips, the site of tuber induction. This movement of RNA originates in source leaf veins and petioles and is induced by a short-day photoperiod, regulated by the untranslated regions, and correlated with enhanced tuber production. Addition of the StBEL5 untranslated regions to another *** mRNA resulted in its preferential transport to stolon tips leading to increased tuber production. Upon fusion of the untranslated regions of StBEL5 to a β-glucuronidase marker, translation in tobacco protoplasts was repressed by those constructs containing the 3＇ untranslated sequence. The untranslated regions of the StBEL5 mRNA are involved in mediating its long-distance transport and in controlling translation. The 3＇ untranslated sequence contains an abundance of conserved motifs that may serve as binding motifs for RNA-binding proteins. Because of their presence in the phloem sieve tube system, their unique untranslated region sequences and their diverse RNA accumulation patterns, the family of BEL1-like RNAs from potato represents a valuable model for studying the long-distance transport of full-length mRNAs and their role in development.

关键词： BEL A Model System of Development Regulated by the Long-distance Transport of mRNA Long

Taxonomic and phylogenetic composition show biotic resistance to exotic invasion in acid seep springs

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Ecological Processes 2021年第1期10卷 77-88页

作者： david F.Barfknecht david j.Gibson School of Biological Sciences Southern Illinois University–CarbondaleCarbondaleIL 62901-6509USA

Background:Few studies have incorporated the evolutionary insights provided by analysis of phylogenetic structure along with community composition to assess the effects of exotic invasion on freshwater ***,we assess the taxonomic and phylogenetic relationships among acid seep springs to investigate the potential homogenization or resistance of communities due to invasion of an exotic ***:Multivariate community analyses indicated differences in community and phylogenetic composition and dispersion among acid seep springs,associated with gradients in soil moisture,canopy cover,and phylogenetic *** contrast,univariate analyses showed differences in taxonomic diversity but not phylogenetic diversity among acid seep ***:Despite exotic invasion,individual acid seep springs remained taxonomically and phylogenetically distinct from each *** and phylogenetic diversity metrics revealed different aspects of composition,reinforcing the importance of including both in analyses of plant communities for understanding community assembly following exotic invasion and for management *** acid seep springs,taxonomic and phylogenetic composition appear to be driven more through environmental filtering by light and moisture than by the competitive effects following invasion of an exotic grass in support of Elton’s biotic resistance hypothesis.

关键词： Acid seep springs Diversity Community Phylogenetics Exotic invasion Environmental filtering NMDS UniFrac Vector analysis

Role of complex organic arsenicals in food in aggregate exposure to arsenic

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journal of Environmental Sciences 2016年第11期28卷 86-96页

作者： david j.Thomas Karen Bradham Pharmacokinetics Branch Integrated Systems Toxicology Division National Health and Environmental Effects Research Laboratory Offilce of Research and Development U.S. Environmental Protection Agency Research Triangle Parle NC 27709 USA Public Health Chemistry Branch Exposure Methods and Measurements Division National Exposure Research Laboratory Offilce of Researchand Development U.S. Environmental Protection Agency Research Triangle Park NC 27709 USA

For much of the world＇s population, food is the major source of exposure to *** to this non-essential metalloid at relatively low levels may be linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important in assessing risk and developing strategies that protect public health. Although most emphasis has been placed on inorganic arsenic as human carcinogen and toxicant, an array of arsenic-containing species are found in plants and animals used as foods. Here,we 2evaluate the contribution of complex organic arsenicals（arsenosugars, arsenolipids,and trimethylarsonium compounds） that are found in foods and consider their origins,metabolism, and potential toxicity. Commonalities in the metabolism of arsenosugars and arsenolipids lead to the production of di-methylated arsenicals which are known to exert many toxic effects. Evaluating foods as sources of exposure to these complex organic arsenicals and understanding the formation of reactive metabolites may be critical in assessing their contribution to aggregate exposure to arsenic.

关键词： Arsenic Arsenobetaine Arsenolipids Arsenosugars

Diet for stroke prevention

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Stroke & Vascular Neurology 2018年第2期3卷 44-50页

作者： j david Spence Stroke Prevention&Atherosclerosis Research Centre Robarts Research InstituteLondonOntarioCanada Neurology and Clinical Pharmacology University of Western OntarioLondonOntarioCanada

Lifestyle is far more important than most physicians *** changes in China that have resulted from increased prosperity are probably responsible for a marked rise in coronary risk in the past several decades,accelerating in recent *** of meat and eggs has increased,while intake of fruits,vegetables and whole grains has *** 2003 and 2013,coronary mortality in China increased 213%,while stroke mortality increased by 26.6%.Besides a high content of cholesterol,meat(particularly red meat)contains carnitine,while egg yolks contain *** are converted by the intestinal microbiome to trimethylamine,in turn oxidised in the liver to trimethylamine n-oxide(TMAO).TMAO causes atherosclerosis in animal models,and in patients referred for coronary angiography high levels after a test dose of two hard-boiled eggs predicted increased cardiovascular *** strongest evidence for dietary prevention of stroke and myocardial infarction is with the Mediterranean diet from Crete,a nearly vegetarian diet that is high in beneficial oils,whole grains,fruits,vegetables and *** at risk of stroke should avoid egg yolk,limit intake of red meat and consume a diet similar to the Mediterranean diet.A crucial issue for stroke prevention in China is reduction of sodium *** changes,although difficult to implement,represent an important opportunity to prevent stroke and have the potential to reverse the trend of increased cardiovascular risk in China.

关键词： prevention intake mortality

Cardioembolic stroke:everything has changed

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Stroke & Vascular Neurology 2018年第2期3卷 76-83页

作者： j david Spence Stroke Prevention and Atherosclerosis Research Centre Robarts Research InstituteWestern UniversityLondonOntarioCanada

Historically,because of the difficulty of using warfarin safely and effectively,many patients with cardioembolic stroke who should have been anticoagulated were instead given ineffective antiplatelet therapy(or no antithrombotic therapy).With the arrival of new oral anticoagulants that are not significantly more likely than aspirin to cause severe haemorrhage,everything has *** antiplatelet agents are much less effective in preventing cardioembolic stroke,it is now more prudent to anticoagulate patients in whom cardioembolic stroke is strongly *** advances include the recognition that intermittent atrial fibrillation is better detected with more prolonged monitoring of the cardiac rhythm,and that percutaneous closure of patent foramen ovale(PFO)may reduce the risk of ***,because in most patients with stroke and PFO the PFO is incidental,this should be reserved for patients in whom paradoxical embolism is likely.A high shunt grade on transcranial Doppler saline studies,and clinical clues to paradoxical embolism,can help in appropriate selection of patients for percutaneous *** patients with atrial fibrillation who cannot be anticoagulated,ablation of the left atrial appendage is an emerging *** is also increasingly recognised that high levels of homocysteine,often due to undiagnosed metabolic deficiency of vitamin B_(12),markedly increase the risk of stroke in atrial fibrillation,and that B vitamins(folic acid and B_(12))do prevent stroke by lowering ***,with regard to B_(12),methylcobalamin should probably be used instead of *** important considerations for judicious application of therapies to prevent cardioembolic stroke are discussed.

关键词： vitamin markedly likely

An In Vivo Experimental Validation of a Computational Model of Human Foot

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journal of Bionic Engineering 2009年第4期6卷 387-397页

作者： Christopher j.Nester david Howard Centre for Health Sport and Rehabilitation Sciences ResearchUniversity of Salford Salford M5 4WTUK

Reliable computational foot models offer an alternative means to enhance knowledge on the biomechanics of human foot. Model validation is one of the most critical aspects of the entire foot modeling and analysis *** paper presents an in vivo experiment combining motion capture system and plantar pressure measure platform to validate a three-dimensional finite element model of human *** Magnetic Resonance Imaging(MRI)slices for the foot modeling and the experimental data for validation were both collected from the same volunteer *** validated components included the comparison of static model predictions of plantar force,plantar pressure and foot surface deformation during six loading conditions,to equivalent measured *** the whole experiment,foot surface deformation,plantar force and plantar pressure were recorded simultaneously during six different loaded standing *** predictions of the current FE model were in good agreement with these experimental results.

关键词： human foot computational model plantar pressure

Controlling resistant hypertension

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Stroke & Vascular Neurology 2018年第2期3卷 69-75页

作者： j david Spence Stroke Prevention&Atherosclerosis Research Centre Robarts Research InstituteWestern UniversityLondonOntarioCanada

Resistant hypertension(failure to achieve target blood pressures with three or more antihypertensive drugs including a diuretic)is an important and preventable cause of *** is highly prevalent in China(>60%of persons above age 65),and only~6%of hypertensives in China are controlled to target *** strokes occur among persons with resistant hypertension;approximately half of strokes could be prevented by blood pressure *** for uncontrolled hypertension include(1)non-compliance;(2)consumption of substances that aggravated hypertension,such as excess salt,alcohol,licorice,decongestants and oral contraceptives;(3)therapeutic inertia(failure to intensify therapy when target blood pressures are not achieved);and(4)diagnostic inertia(failure to investigate the cause of resistant hypertension).In China,an additional factor is lack of availability of appropriate antihypertensive therapy in many healthcare *** restriction in combination with a diet similar to the Cretan Mediterranean or the DASH(Dietary Approaches to Stop Hypertension)diet can lower blood pressure in proportion to the severity of *** individualised therapy for hypertension based on phenotyping by plasma renin activity and aldosterone can markedly improve blood pressure *** hypertension(high renin/high aldosterone)is best treated with angiotensin receptor antagonists;primary aldosteronism(low renin/high aldosterone)is best treated with aldosterone antagonists(spironolactone or eplerenone);and hypertension due to overactivity of the renal epithelial sodium channel(low renin/low aldosterone;Liddle phenotype)is best treated with *** latter is far more common than most physicians suppose.

关键词： hypertension hypertensive markedly

Modelling of a Human Driver’s Interaction with Vehicle Automated Steering Using Cooperative Game Theory

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IEEE/CAA journal of Automatica Sinica 2019年第5期6卷 1095-1107页

作者： Xiaoxiang Na david j.Cole Department of Engineering University of Cambridge

The introduction of automated driving systems raised questions about how the human driver interacts with the automated system. Non-cooperative game theory is increasingly used for modelling and understanding such interaction, while its counterpart, cooperative game theory is rarely discussed for similar applications despite it may be potentially more suitable. This paper describes the modelling of a human driver’s steering interaction with an automated steering system using cooperative game theory. The distributed Model Predictive Control approach is adopted to derive the driver’s and the automated steering system’s strategies in a Pareto equilibrium sense, namely their cooperative Pareto steering strategies. Two separate numerical studies are carried out to study the influence of strategy parameters, and the influence of strategy types on the driver’s and the automated system’s steering performance. It is found that when a driver interacts with an automated steering system using a cooperative Pareto steering strategy, the driver can improve his/her performance in following a target path through increasing his/her effort in pursuing his/her own interest under the driver-automation cooperative control goal. It is also found that a driver’s adoption of cooperative Pareto steering strategy leads to a reinforcement in the driver’s steering angle control, compared to the driver’s adoption of non-cooperative Nash strategy. This in turn enables the vehicle to return from a lane-change maneuver to straight-line driving swifter.

关键词： Automated driving system cooperative game theory driver modelling

DNA damage, NF-κB and accelerated aging

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Asian journal of Andrology 2012年第6期14卷 811-812页

作者： david G Le Couteur david j Handelsman ANZAC Medical Research Institute Sydney 2139 Australia Centre for Education and Research on Ageing (CERA) Concord Hospital and University of Sydney Concord NSW 2139 Australia

The aging process is the major risk factor for disease and disability yet the cel- lular mechanisms for aging are uncertain.

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