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A case study on Landscape Component Niche based on Landscape Pattern Indices: Yanchi,Ningxia Province, China

Research in Cold and Arid Regions 2020年第1期12卷 22-33页

作者： XiaoNing Zhang XueLu liu Ghanney philip XiaoDan Li QuanXi Wang YaNan Xu tingting Hui College of Resources and Environmental Sciences Gansu Agricultural UniversityLanzhouGansu 730070China College of Management Gansu Agricultural UniversityLanzhouGansu 730070China

Yanchi County is located in the agro-pastoral ecotone and belongs to the ecologically fragile area of Northwest *** is important to study the evolution of landscape pattern to curb its environmental *** order to intuitively show how the landscape pattern of the study area changes over time,Landsat thematic Mappers(tM)and Landsat Operational Land Imager(OLI)data of 1991,2000,2010 and 2017 were *** paper attempts to apply niche theories and methods into landscape ecology,and constructs a niche model of landscape components by using"n-dimentional hypervolume niche theory"and landscape pattern *** evaluating the spatial and temporal evolution of niche from the perspective of two-dimensional space to reflect the changes of landscape pattern in the study area over the past 26 years,new theories and methods were introduced for the characterization of landscape *** results indicate that:1)the larger the attribute and dominance value of landscape components,the higher the ecological niche and the stronger the control effect on the overall landscape.2)the ecological niche of each landscape component was significantly different,just as its control effect on the overall landscape.3)the dynamic change of the ecological niche of each landscape component was different,with grassland,unused land and arable land always in a high dominant position,although the ecological niche of construction land and water area was always *** general,the introduction of niche theory into the landscape ecology provided a new method to study the changes in regional landscape pattern.

关键词： landscape pattern landscape component niche landscape stability landscape dominance

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Management of portal hypertension in children

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World Journal of Gastroenterology 2012年第11期18卷 1176-1184页

作者： Roberto Gugig philip Rosenthal Pediatric Gastroenterology Hepatology and Nutrition Deprtment of PediatricsUniversity of California

Portal hypertension can be caused by a wide variety of *** frequently presents with bleeding from esophageal *** approach to acute variceal hemorrhage in children is a stepwise progression from least invasive to most *** of acute variceal bleeding is *** data on primary prophylaxis and long term management prevention of recurrent variceal bleeding in children is scarce,therefore prospective multicenter trials are needed to establish best practices.

关键词： Portal hypertension Variceal hemorrhage Children

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the Influence of Underlying Stresses from Environmental Hazards on Resilience in Bangladesh: A System View

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International Journal of Disaster Risk Science 2019年第4期10卷 511-528页

作者： philip Lake Richard Fenner Building Sustainability Group ArupLondon W1T 4BQUK Centre for Sustainable Development Engineering DepartmentCambridge UniversityCambridge CB21TNUK

Bangladesh is one of the countries most vulnerable to climate change,while its people also suffer from a range of environmental hazards linked to the growing prevalence of non-communicable *** diseases are responsible for increasing morbidity and mortality and lead to other stresses within the *** stresses create continuous impacts on the health and well-being of the population,compounding their vulnerability and inhibiting their capacity to cope with frequent event-related shocks,such as floods and drought.A systems approach is taken to examine four important environmental hazards in Bangladesh—arsenic contamination of drinking water,arsenic transmission through the food chain,indoor air quality,and air pollution.A review of these hazards is presented in a conceptual framework that links human well-being with the key system components of infrastructure,institutions,knowledge,and *** reveals key underlying factors between the hazards and uncovers system structures that can lead to more effective hazard mitigation,and the establishment of strategic intervention *** article concludes that elimination of these continuous stresses will only come about through the culmination of multiple interventions over time,undertaken in an iterative manner that builds on the continual advancement of hazard *** role of individual behaviors,together with factors such as risk awareness and perception of the hazards,has been identified as crucial for achieving successful mitigation *** knowledge of the hazards,public awareness,and government accountability are focus points to reduce population exposure and enhance response capacity.

关键词： Air pollution Arsenic contamination Bangladesh Drinking water contamination Environmental hazards Resilience

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A proposed U.S./China theoretical/experimental collaborative effort on baryon resonance extraction

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Chinese Physics C 2009年第12期33卷 1222-1229页

作者： philip L. Cole Idaho State University Department of Physics Pocatello Idaho 83209-8106 USA

In this paper we discuss the reasons for our work towards establishing a new collaboration between Jefferson Lab （JLab） and the Institute of High Energy Physics （IHEP） in Beijing. We seek to combine experimentalists and theorists into a dedicated group focused on better understanding the current and future data from JLab and from the Beijing Electron Positron Collider （BEPC）. Recent JLab results on the extraction of single- and double-polarization observables in both the lπ- and 2π-channel show their high sensitivity to small production amplitudes and therefore their importance for the extraction of resonance parameters. the Beijing Electron Spectrometer （BES） at the BEPC has collected high statistics data on J/ψ production. Its decay into baryon-antibaryon channels offers a unique and complementary way of probing nucleon resonances. the CEBAF Large Acceptance Spectrometer, CLAS, has access to N＊ form factors at high Q2 which is advantageous for the study of dynamical properties of nucleon resonances, while the low-background BES results will be able to provide guidance for the search for less-dominant excited states at JLab. Moreover, with the recently approved experimental proposal Nucleon Resonance Studies with CLAS12 and the high-quality data streaming from BES-Ⅲand CLAS, the time has come for forging a new trans-Pacific collaboration of theorists and experimentalists on NStAR physics.

关键词： baryon resonances electromagnetic form factors J/ψ production CEBAF Large AcceptanceSpectrometer (CLAS) Jefferson Laboratory (JLab) Beijing Electron Spectrometer (BES) Beijing ElectronPositron Collider (BEPC) Institute of High Energy Physics (IHEP)

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Interleukin-1 and estrogen protect against disseminating dentoalveolar infections

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International Journal of Oral Science 2017年第1期9卷 16-23页

作者： hesham youssef philip stashenko host-microbiome center department of applied oral sciencesthe forsyth instituteCambridgeUSA

Dentoalveolar bacterial infections cause localized tissue and bone destruction, but usually remain well-localized within teeth in immunocompetent hosts. However, in certain cases these infections may invade head and neck tissues, resulting in orofacial abscesses, cellulitis and sepsis, with resultant high morbidity and even mortality. In the present studies, we developed a novel model of spreading dentoalveolar infections in mice by treatment with neutralizing antibodies against both interleukin-la （IL-1a） and IL-1β. Surprisingly male but not female mice given anti-lL-1 antibodies developed orofacial abscesses, weight loss, splenomegaly and sepsis. Female mice developed abscesses and sepsis comparable to males following ovariectomy （OVX）, which was reversed by estrogen supplementation. Anti-lL-1 blockade inhibited IL-12, interferon y （IFNy） and IL-6 but not IL-IO expression in infrabony lesions, suggestive of a local anti-inflammatory response. there was greater infiltration of neutrophils and other inflammatory ceils into lesions in anti-lL-l-treated animals; however, blood leukocytes had reduced bacterial phagocytic and killing activity ex vivo. Estrogen directly stimulated IL-1 production by macrophages, suggesting that the resistance of females to disseminating dentoalveolar infections may be due to their heightened pro-inflammatory responses following bacterial challenge, leading to enhanced localization of these infections.

关键词： cytokines dentoalveolar disseminating infections estrogen neutrophils

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Model-based and Fuzzy Logic Approaches to Condition Monitoring of Operational Wind turbines

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International Journal of Automation and computing 2015年第1期12卷 25-34页

作者： philip Cross Xiandong Ma Engineering Department Lancaster University

It is common for wind turbines to be installed in remote locations on land or offshore, leading to difficulties in routine inspection and maintenance. Further, wind turbines in these locations are often subject to harsh operating conditions. these challenges mean there is a requirement for a high degree of maintenance. the data generated by monitoring systems can be used to obtain models of wind turbines operating under different conditions, and hence predict output signals based on known inputs. A model-based condition monitoring system can be implemented by comparing output data obtained from operational turbines with those predicted by the models, so as to detect changes that could be due to the presence of faults. this paper discusses several techniques for model-based condition monitoring systems: linear models, artificial neural networks, and state dependent parameter "pseudo" transfer *** models are identified using supervisory control and data acquisition(SCADA) data acquired from an operational wind firm. It is found that the multiple-input single-output state dependent parameter method outperforms both multivariate linear and artificial neural network-based approaches. Subsequently, state dependent parameter models are used to develop adaptive thresholds for critical output signals. In order to provide an early warning of a developing fault, it is necessary to interpret the amount by which the threshold is exceeded, together with the period of time over which this occurs. In this regard, a fuzzy logic-based inference system is proposed and demonstrated to be practically feasible.

关键词： Condition monitoring wind turbines artificial neural network state dependent parameter model fuzzy logic

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Double-up for single-ion masses

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Nuclear Science and techniques 2023年第7期34卷 159-161页

作者： philip M.Walker Department of Physics University of SurreyGuildford GU27XHUK

A cunning addition for the determination of nuclear masses provides world-leading sensitivity for accurate *** is already opening up new physics and *** may sound simple to weigh an atomic nucleus,but there is more to it than you might think,especially when the nucleus is very *** out the properties of such fleeting nuclei,perhaps surviving for only a few milliseconds,can solve long-standing science ***-lived nuclei are key to our understanding not only of how neutrons and protons bind together in nuclei,but also of the way that explosive events in the cosmos tell us about the life cycle of stars.

关键词： addition unstable stars

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RNA:掌控生命后台

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环球科学 2024年第13期 24-31页

作者：菲利普·鲍尔付向东(翻译) 不详西湖大学生命科学学院和医学院

数一年的研究表明,大量曾被科学家认为是“垃圾DNA”的区域,实际会编码一种名为非编码RNA的分子。这些RNA不会参与蛋白质合成,却会以多种方式影响生命运作,并为药物开发提供了新的方向。21世纪初,人类基因组的30亿个DNA组成单元差不多... 详细信息

数一年的研究表明,大量曾被科学家认为是“垃圾DNA”的区域,实际会编码一种名为非编码RNA的分子。这些RNA不会参与蛋白质合成,却会以多种方式影响生命运作,并为药物开发提供了新的方向。21世纪初,人类基因组的30亿个DNA组成单元差不多已全部鉴定完成。彼时,一群科学家正试图弄清楚所有DNA的功能,其中就包括现就职于美国国立卫生研究院(NIH)的遗传学家托马斯·金格拉斯(thomas Gingeras)。

关键词：遗传学家人类基因组蛋白质合成非编码RNA 药物开发 DNA

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Blueprints for real-world invisibility

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Frontiers of physics 2018年第5期13卷 1-2页

作者： philip Ball East Dulwich London SE22 UK.

Making objects invisible has never been easy. A seventeenth-century magic spell for growing ＂beans of invisibility＂ instructed that they should be buried with the severed head of a man who committed suicide. For H. G. Wells＇s ＂invisible man＂ in his famous 1897 novel, the process was more scientific, involving the use of mysteri- ous rays related to X-rays that would alter the refractive index of a transparent substance to match that of air.

关键词： Blueprints real-world invisibility

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Bending the laws of optics with metamaterials: an interview with John Pendry

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National Science Review 2018年第2期5卷 200-202页

作者： philip Ball philip Ball writes for NSR from London

Metamaterials show us that nature’s laws might not always be as fixed as they seem to *** of the laws of optics,for example,states that a light ray passing from one transparent medium to another—air to water or glas... 详细信息

关键词： PHYSICIStS MEtAMAtERIALS

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