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中国有色金属学会会刊：英文版 2006年第B01期16卷 146-153页

作者： Susan z.HUA Matthew R.SULL IVAN jason N.ARMSTRONG Materials Program Mechanical and Aerospace Engineering DepartmentState University of New York at BuffaloBuffaloNY 14260USA

Recent work on magnetic quantum point contacts (QPCs) was discussed. Complete magnetoresistance loops across Co QPCs as small as a single atom was measured. The remarkable feature of these QPCs is the rapid oscillatory decay in magnetoresistance with the increase of contact size. In addition, stepwise or quantum magnetoresistance loops are observed, resulting from varying transmission probability of the available discrete conductance channels because the sample is cycled between the ferromagnetic (F) and antiferromagnetic (AF) aligned states. Quantized conductance combined with spin dependent transmission of electron waves gives rise to a multi-channel system with a quantum domain wall acting as a valve, i.e., a quantum spin-valve. Behavior of a few-atom QPC is built on the behavior of a single-atom QPC and hence the summarization of results as ‘single-atom spintronics’. An evolutionary trace of spin-dependent electron transmission from a single atom to bulk is provided, the requisite hallmarks of artefact-free magnetoresistance is established across a QPC – stepwise or quantum magnetoresistance loops and size dependent oscillatory magnetoresistance.

关键词：单原子自旋电子学量子点接触电子波导振荡磁阻

Protective Role of Heme Oxygenase-2 against Apoptosis in LLC-PK1 Cells:Effects of Non-porphyrin,Imidazole-based Heme Oxygenase Inhibitors

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Protective Role of Heme Oxygenase-2 against Apoptosis in LLC...

WHAT ARE THE DIFFERENCES OF POLYMER SURFACE RELAXATION FROM THE BULK?

第十五届国际药理学大会

作者： Kinobe Robert vlahakis jason Brien James Szarek Walter Nakatsu Kanji Dept.Pharmacology ＆ Toxicology Queen’s University Dept. Chemistry Queen’s University Dept. Pharmacology ＆ Toxicology Queen’s University Dent.Chemistry Queen’s University Dept.Pharmacology ＆ Toxicology Queen’s University

＜正＞ Heme oxygenase （HO） isozymes are involved in the biotransformation of heme to biliverdin/bilirubin. iron and carbon monoxide （CO）. HO - 1 is induced by ox-idative stress while HO - 2 is constitutively expressed. To enhance our understanding of the physiological roles of HO isozymes. we have developed novel imidazolebasedHO inhibitors. Unlike the metalloporphyrins,these compounds are selective for the inhibition of HO with minimal effects on most other heme - dependent enzymes. In the current study, we examined the effects of the imidazole - based HO inhibitors on tumour necrosis factor （TNF） - induced apoptosis in wild type and HO - 2 stably transfected,LLC - PK1 cells. TNF - alpha caused significant cytotoxicity in wild type cells （P＜0.05）. but not HO - 2 overexpressingcells, and this decrease in cell viability was significantly enhanced by a sublethal dose （2 - 25μM） of the imidazole - based HO inhibitors （P＜0.05）. Pretreatment with hemin （10μM） increased HO - 1 expression but was not *** data are consistent with a cytoprotective role of HO - 2 in LLC -PK1 cells.

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Chinese Journal of Polymer Science 2011年第1期29卷 81-86页

作者： Ian Mann Ryan M.Van Horn jason J.Ge Matthew J.Graham Frank W.Harris Stephen z.D.Cheng College of Polymer Science and Polymer Engineering Department of Polymer Sciencethe University of Akron

The polymer surface relaxation in thin films has been a long debating issue. We report a new method on studying surface relaxation behaviors of polymer thin films on a solid substrate. This method involved utilizing a rubbed polyimide surface with a pretilting angle in a liquid crystalline cell. Due to the surface alignment, the liquid crystals were aligned along the rubbing direction. During heating the liquid crystalline cell, we continuously monitored the change of orientation of the liquid crystals. It is understood that at a temperature where the orientation of liquid crystal is lost, the surface relaxation on the glass substrate takes place to lose the polyimide surface orientation. It was found that the relaxation temperature at which the liquid crystals lose their orientation depends on the film thickness of the polyimide. A quantitative linear relationship between the relaxation temperature and reciprocal of the film thickness can be observed. Furthermore, different topologies of the rubbed and relaxed thin films were amplified using the polyethylene decoration method and observed using atomic force microscopy.

关键词： Surface relaxation Liquid crystal orientation Polyethylene decoration.

Description of the song of the Nilgiri Thrush(zoothera [aurea] neilgherriensis) and song differentiation across the zoothera dauma species complex

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Avian Research 2018年第3期9卷 273-279页

作者： jason T.Weir Department of Ecology and Evolutionary Biology University of Toronto Department of Biological Sciences University of Toronto Scarborough Department of Natural History Royal Ontario Museum

Background: Taxonomic treatment of the zoothera dauma species complex is highly variable and has been hampered by the absence of song recordings for the Nilgiri Thrush(zoothera [aurea] neilgherriensis).Methods: I obtained two recordings of the song of neigherriensis from southern Indian. Here I publish sonograms and analyze song recordings for all but one currently described taxon from the Eurasian portion of the geographic range of this species complex. Principal component analyses were used to investigate song differences between ***: The song of neigherriensis is a highly complex series of strophes remarkably similar to the song of the insular zoothera major. Vocal analyses across the complex indicate four key groups of taxa differentiated in their songs:(1) simple flat whistled songs which include the northern aurea, toratugumi and the undescribed Taiwan population;(2) eastern populations of dauma(reported here for the first time) which sing like northern birds but with much broader bandwidth,(3) strongly down-slurred, thin whistles of tropical resident imbricata of Sri Lanka and horsfieldi of Indonesia, and(4) highly complex songs of Himalayan dauma, neilgherriensis and ***: zoothera dauma is unlikely to represent a single species given the simple singing populations from its eastern range and highly complex song from the Himalayan portion of its range. neilgherriensis should either be transferred from zoothera aurea, where it is currently classified as a subspecies, and be placed as a subspecies within z. dauma from the Himalayas or it should be recognized as a distinct species. Given the small number of songs available for analyses, I suggest the former course until it can be clearly demonstrated that neilgherriensis and Himalayan dauma are vocally distinct.

关键词： Nilgiri Thrush neilgherriensis zoothera dauma Song Taxonomy

ADVANCES IN SUSTAINABLE SECURITY SYSTEMS ENGINEERING WITH DRAMA THEORY (DT) Ⅱ

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Journal of Systems Science and Systems Engineering 2009年第4期18卷 403-422页

作者： jason K. LEVY Nigel HOWARD Wilder School of Government and Public Affairs Virginia Commonwealth University Sheffield Hallam University

We put forth Drama Theory II （DT II） as a formal multiple participant decision making framework that can be used to systematically model complex security challenges, and advance the field of Sustainable Security Systems Engineering. DT II is defined as a theory of ＂large world＂ pre-game communication and equilibrium selection. While game theoretic tools have been widely applied to resolve environmental conflicts and promote global security, traditional game theory assumes that decision makers, options, and preferences are fixed. A mathematical treatment of key drama theoretic concepts （i.e. positions, intentions, doubts and dilemmas） is provided. The dynamics of the drama theoretic process are discussed and the expected equilibrium set is derived. The fundamental theorem of drama theory is proven and all theoretical results are applied to promote sustainable security solutions. It is emphasized that DT II represents a flexible systems engineering technique to address time-sensitive, multi-faceted, and complex multiple participant negotiations.

关键词： Drama Theory II sustainable security systems engineering game theory

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren Tan Mary C.Stephenson Sharifah Badriyah Alhadad Kelvin W.z.Loh Tuck Wah Soong jason K.W.Lee Ivan C.C.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore Centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance Centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore Campus for Research Excellence and Technological Enterprise(CREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity Cognition Heat stress Hyperthermia Motor function

Barriers to Insurance as a Flood Risk Management Tool:Evidence from a Survey of Property Owners

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International Journal of Disaster Risk Science 2020年第3期11卷 263-273页

作者： jason Thistlethwaite Daniel Henstra Craig Brown Daniel Scott School of Environment Enterprise and DevelopmentUniversity of WaterlooWaterlooON N2L 3G1Canada Department of Political Science University of WaterlooWaterlooON N2L 3G1Canada Climate Change and Health Adaptation Planning Vancouver Coastal HealthVancouverBC V5Z 4C2Canada Department of Geography and Environmental Management University of WaterlooWaterlooON N2L 3G1Canada

By using risk-adjusted price signals to transfer responsibility for property-level flood protection and recovery from governments to property owners,flood insurance represents a key tenet of the flood risk management(FRM)*** Government of Canada has worked with insurers to introduce flood insurance for the first time as a part of a broader shift towards FRM to limit the growing costs of *** viability of flood insurance in Canada,however,has been questioned by research that disputes the utility of purchasing coverage by property *** study tested this assumption by drawing on public opinion survey data to assess factors that influence decisions about the utility of *** findings reveal that Canadians have limited knowledge of flood insurance coverage,exhibit a low willingness-to-pay for both insurance and property-level flood protection measures,and expect governments to shoulder much of the financial burden of flood recovery through disaster assistance.

关键词： Flood insurance Flood risk management Risk-sharing Willingness-to-pay

Machine Learning Analysis of Impact of Western US Fires on Central US Hailstorms

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Advances in Atmospheric Sciences 2024年第7期41卷 1450-1462页

作者： Xinming LIN Jiwen FAN Yuwei zHANG zjason HOU Pacific Northwest National Laboratory RichlandWA 99354USA Argonne National Laboratory LemontIL 60439USA

Fires,including wildfires,harm air quality and essential public services like transportation,communication,and *** fires can also influence atmospheric conditions,including temperature and aerosols,potentially affecting severe convective ***,we investigate the remote impacts of fires in the western United States(WUS)on the occurrence of large hail(size:≥2.54 cm)in the central US(CUS)over the 20-year period of 2001–20 using the machine learning(ML),Random Forest(RF),and Extreme Gradient Boosting(XGB)*** developed RF and XGB models demonstrate high accuracy(>90%)and F1 scores of up to 0.78 in predicting large hail occurrences when WUS fires and CUS hailstorms coincide,particularly in four states(Wyoming,South Dakota,Nebraska,and Kansas).The key contributing variables identified from both ML models include the meteorological variables in the fire region(temperature and moisture),the westerly wind over the plume transport path,and the fire features(i.e.,the maximum fire power and burned area).The results confirm a linkage between WUS fires and severe weather in the CUS,corroborating the findings of our previous modeling study conducted on case simulations with a detailed physics model.

关键词： wildfire severe convective storm hailstorm machine learning

Review and synthesis of the effects of climate change on amphibians

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Integrative zoology 2013年第2期8卷 145-161页

作者： Yiming LI Jeremy M.COHEN jason R.ROHR Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Department of Integrative Biology University of South FloridaTampaFLUSA

Considerable progress has been made in understanding the responses of amphibians to climate change,with successful research carried out on climate change-associated shifts in amphibian phenology,elevational distributions and amphibian-parasite *** review and synthesize the literature on this topic,emphasizing acutely lethal,sublethal,indirect and positive effects of climate change on amphibians,and major research *** instance,evidence is lacking on poleward shifts in amphibian distributions and on changes in body sizes and morphologies of amphibians in response to climate *** have limited information on amphibian thermal tolerances,thermal preferences,dehydration breaths,opportunity costs of water conserving behaviors and actual temperature and moisture ranges amphibians *** when much of this information is available,there remains little evidence that climate change is acutely lethal to *** suggests that if climate change is contributing to declines,it might be through effects that are not acutely lethal,indirect,or both,but evidence in support of this suggestion is *** fact,evidence that climate change is directly contributing to amphibian declines is weak,partly because researchers have not often ruled out alternative hypotheses,such as chytrid fungus or climate-fungus ***,we recommend that amphibian-climate research shift from primarily inductive,correlational approach as to studies that evaluate alternative hypotheses for *** additional rigor will require interdisciplinary collaborations,estimates of costs and benefits of climate change to amphibian fitness and populations,and the integration of correlative field studies,experiments on‘model’amphibian species,and mathematical and functional,physiological models.

关键词： amphibian decline Batrachochytrium dendrobatidis breeding date climate-linked epidemic hypothesis global warming