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Towards More Snow days in Summer since 2001 at the Great Wall Station,Antarctic Peninsula:The Role of the Amundsen Sea Low

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Advances in Atmospheric Sciences 2020年第5期37卷 494-504页

作者： Minghu dING Wei HAN Tong ZHANG Xiaoyuan YUE jeremy FYKE Ge LIU Cunde XIAO State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Fluid dynamics and Solid Mechanics Group Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA Associated Engineering Group LtdVernonBritish Columbia V1T 9P9Canada State Key Laboratory of Earth Surface and Resource Ecology Beijing Normal UniversityBeijing 100875China Beijing Meteorological Observation Center Beijing 100176China

The variation in the precipitation phase in polar regions represents an important indicator of climate change and *** studied the precipitation phase at the Great Wall Station and Antarctic Peninsula(AP)region,based on daily precipitation,synoptic records and ERA-Interim data during the austral summers of 1985?***,there was no trend in the total precipitation amount or days,but the phase of summer precipitation(rainfall days versus snowfall days)showed opposite trends before and after 2001 at the *** total summer rain days/snow days increased/decreased during 1985?2001 and significantly decreased at a rate of?14.13 d(10 yr)?1/increased at a rate of 14.31 d(10 yr)?1 during 2001?2014,agreeing well with corresponding variations in the surface air ***,we found that the longitudinal location of the Amundsen Sea low(ASL)should account for the change in the precipitation phase since 2001,as it has shown a westward drift after 2001[?41.1°(10 yr)?1],leading to stronger cold southerly winds,colder water vapor flux,and more snow over the AP region during *** study points out a supplementary factor for the climate variation on the AP.

关键词： precipitation phase Great Wall Station Amundsen Sea Low

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Quantifying Malware Evolution through Archaeology

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Journal of Information Security 2015年第2期6卷 101-110页

作者： jeremy d. Seideman Bilal Khan Cesar Vargas The Graduate School and University Center (CUNY) New York USA department of Math and Computer Science John Jay College (CUNY) New York USA NacoLabs Consulting LLC New York USA

dynamic analysis of malware allows us to examine malware samples, and then group those samples into families based on observed behavior. Using Boolean variables to represent the presence or absence of a range of malware behavior, we create a bitstring that represents each malware behaviorally, and then group samples into the same class if they exhibit the same behavior. Combining class definitions with malware discovery dates, we can construct a timeline of showing the emergence date of each class, in order to examine prevalence, complexity, and longevity of each class. We find that certain behavior classes are more prevalent than others, following a frequency power law. Some classes have had lower longevity, indicating that their attack profile is no longer manifested by new variants of malware, while others of greater longevity, continue to affect new computer systems. We verify for the first time commonly held intuitions on malware evolution, showing quantitatively from the archaeological record that over 80% of the time, classes of higher malware complexity emerged later than classes of lower complexity. In addition to providing historical perspective on malware evolution, the methods described in this paper may aid malware detection through classification, leading to new proactive methods to identify malicious software.

关键词： Malware Classification Evolution dynamic Analysis

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Utilizing dimensional Analysis with Observed data to determine the Significance of Hydrodynamic Solutions in Coastal Hydrology

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Computational Water, Energy, and Environmental Engineering 2014年第2期3卷 57-77页

作者： Eric d. Swain jeremy d. decker Joseph d. Hughes US Geological Survey Florida Water Science Center Fort Lauderdale USA US Geological Survey Florida Water Science Center Tampa USA

In this paper, the authors present an analysis of the magnitude of the temporal and spatial acceleration (inertial) terms in the surface-water flow equations and determine the conditions under which these inertial terms have sufficient magnitude to be required in the computations. data from two South Florida field sites are examined and the relative magnitudes of temporal acceleration, spatial acceleration, and the gravity and friction terms are compared. Parameters are derived by using dimensionless numbers and applied to quantify the significance of the hydrodynamic effects. The time series of the ratio of the inertial and gravity terms from field sites are presented and compared with both a simplified indicator parameter and a more complex parameter called the Hydrodynamic Significance Number (HSN). Two test-case models were developed by using the SWIFT2d hydrodynamic simulator to examine flow behavior with and without the inertial terms and compute the HSN. The first model represented one of the previously-mentioned field sites during gate operations of a structure-managed coastal canal. The second model was a synthetic test case illustrating the drainage of water down a sloped surface from an initial stage while under constant flow. The analyses indicate that the times of substantial hydrodynamic effects are sporadic but significant. The simplified indicator parameter correlates much better with the hydrodynamic effect magnitude for a constant width channel such as Miami Canal than at the non-uniform North River. Higher HSN values indicate flow situations where the inertial terms are large and need to be taken into account.

关键词： Hydrodynamic dimensional Analysis Coastal Numerical Modeling

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Assessment of an Evapotranspiration deficit drought Index in Relation to Impacts on Ecosystems

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Advances in Atmospheric Sciences 2019年第11期36卷 1273-1287页

作者： Xia ZHANG Mingxing LI Zhuguo MA Qing YANG Meixia LV Robin clark Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Met Office Hadley Centre Exeter EX 1 3PB UK

Ecosystems have increasingly been subject to the challenge of heavy drought under global warming. To quantitatively evaluate the impacts of drought on ecosystems, it is necessary to develop a drought index that can sensitively depict the response of vegetation to drought evolution at a biological time scale. For the ability of direct connection between climate and ecosystem by deficit of evapotranspiration, in the present study, a drought index was defined based on standardized evapotranspiration deficit (SEdI), according to the difference between actual and potential evapotranspiration, to meet the need for highlighting drought impacts on ecological processes. Comparisons with traditional indices show that SEdI can reasonably detect droughts and climatic dry and wet transitions, especially at a monthly time scale, and can also regenerate long-term trends. Moreover, SEdI can more sensitively capture the biological changes of ecosystems in response to the dynamics of drought intensity, compared with the indices of precipitation and temperature. SEdI is more practical than the precipitation and temperature indices to highlight signals of biological effects in climate droughts. Hence, it has potential for use in assessments of climate change and its impact on ecosystems.

关键词： evapotranspiration drought index vegetation ecosystem leaf area index climate change

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Increasing Flash Floods in a drying Climate over Southwest China

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Advances in Atmospheric Sciences 2018年第8期35卷 198-203页

作者： Chan XIAO Peili WU Lixia ZHANG Robin T. clark National Climate Centre China Meteorological Administration Beijing 100081 China Met Office Hadley Centre FitzRoy Road Exeter EX1 3PB UK Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In a globally warming world, subtropical regions are generally expected to become drier while the tropics and mid-high latitudes become wetter. In line with this, Southwest China, close to 25°N, is expected to become increasingly prone to drought if annual mean precipitation decreases. However, despite this trend, changes in the temporal distribution of moisture supply might actually result in increased extreme rainfall in the region, whose climate is characterized by distinct dry and wet seasons. Using hourly and daily gauge observations, rainfall intensity changes since 1971 are exalnined for a network of 142 locations in the region. From the analysis, dry season changes are negligible but wet season changes exhibit a significantly strong downward trend [-2.4% （10 yr）^-1], particularly during the past 15 years [-17.7% （10 yr）^-1]. However, the intensity of events during the wettest of 5% hours appears to steadily increase during the whole period [1.4% （10 yr）^-1], tying in with government statistical reports of recent droughts and flooding. If the opposing trends are a consequence of a warming climate, it is reasonable to expect the contradictory trend to continue with an enhanced risk of flash flooding in coming decades in the region concerned.

关键词： regional water cycle flash floods drought Southwest China

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Longitudinal changes in cardiac function in the very elderly: the Jerusalem longitudinal cohort study

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Journal of Geriatric Cardiology 2019年第11期16卷 800-805页

作者： david Leibowitz Irit Stessman-Lande Hend Sliman jeremy M Jacobs Jochanan Stessman dan Gilon Jerusalem Institute of Aging Research Hadassah-Hebrew University Medical CenterMount-ScopusJerusalemIsrael Coronary Care Unit Hadassah–Hebrew University Medical CenterMount-ScopusJerusalemIsrael department of Geriatrics and Rehabilitation Hadassah-Hebrew University Medical CenterMount-ScopusJerusalemIsrael

Background People over the age of 85 are a rapidly growing age group with a high incidence of congestive heart failure(CHF),in particular heart failure with preserved ejection fraction(HFp EF).The diagnosis of CHF is challenging and longitudinal data assessing cardiac structure and function are necessary to distinguish physiologic from pathologic cardiac *** objective of the study was to determine longitudinal changes in cardiac struture and function from ages 85 to 94 years using home *** Subjects were recruited from the Jerusalem Longitudinal Cohort *** three members of the initial cohort(32 F,31 M)who underwent home echocardiography at age 85 were the subjects of the current study and underwent repeat home 2-d and doppler echocardiographic assessment at age *** There were no significant longitudinal changes in left ventricular mass index(LVMI),however LV end-diastolic volume significantly decreased from 113.4±30 to 103.6±35.5 m L(Pd stable,however longitudinal systolic function significantly decreased with age from 7.9±1.8 to 6.6±1.4 cm/s2(Pdiastolic function as assessed by increased E:e’(11.2±3.4 to 16±7.5,Pd increased left atrial volume index(34.1±11.3 to 42.4±13.7 m L/m^2,Pduced with *** This study demonstrated preserved EF with decreased longitudinal systolic function and diastolic function without significant change in LV *** in LV function in the very elderly may be independent of changes in LV geometry.

关键词： Echocardiography The elderly Ventricular function

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八字树

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微型计算机 1995年第2期15卷 79-81页

作者： clark,d 李淑兰

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带间级联激光器性能对结构变化的耐受性研究

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红外与毫米波学报 2020年第2期39卷 137-141页

作者：林羽喆 jeremy A.Massengale 黄文祥杨瑞青 Tetsuya d.Mishima Michael B.Santos 中国科学院半导体研究所固态光电信息实验室北京100083 俄克拉荷马大学电子与计算机工程系美国诺曼73019 中国科学院大学材料科学与光电工程中心北京100049 俄克拉荷马大学物理与天文学系美国诺曼73019

通过对两种结构参数与设计偏差较大的带间级联激光器(ICL)的研究,探讨了器件性能在结构变化下的耐受性。在300 K时,即使和4.6μm的设计波长相比蓝移700μm以上,激光器仍然性能良好,其阈值电流密度低至320 A/cm^2。此研究为带间级联激光... 详细信息

通过对两种结构参数与设计偏差较大的带间级联激光器(ICL)的研究,探讨了器件性能在结构变化下的耐受性。在300 K时,即使和4.6μm的设计波长相比蓝移700μm以上,激光器仍然性能良好,其阈值电流密度低至320 A/cm^2。此研究为带间级联激光器在结构变化方面的耐受性提供了坚实的实验依据。

关键词： Ⅲ-Ⅴ族半导体带间级联激光器中红外量子阱 Ⅱ类异质结

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Signaling at the Root Surface： The Role of Cutin Monomers in Mycorrhization

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Molecular Plant 2013年第5期6卷 1381-1383页

作者： jeremy d. Murray donna R. Cousins Kirsty J. Jackson Chengwu Liu Cell and developmental Biology John Innes Centre Norwich NR4 7UH UK

Most vascular plants interact with arbuscular mycorrhizal fungi （AMF） and are thereby provided significant advantages in nutrient acquisition, especially phosphate. The widespread retention of this symbiosis in vascular plants is testament to its importance and ancient origins. This highlight focuses on the reports of two of the first genes identified through for- ward genetic screens for AMF symbiotic mutants： Required for Abuscular Mycorrhization 1 （RAM1） and RAM2, which respectively encode a GRAS transcription factor and a glyc- erol-3-phosphate acyl-transferase （GPAT） that are required for the formation of fungal entry structures （hyphopodia） on the root surface.

关键词：共生植物转录因子转移酶类

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Surface-bound myeloperoxidase is a ligand for recognition of late apoptotic neutrophils by human lung surfactant proteins A and d

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Protein & Cell 2010年第6期1卷 563-572页

作者： Anne Jäkel Howard clark Kenneth B.M.Reid Robert B.Sim department of Pharmacology University of OxfordMansfield RoadOxford OX13QTUK University of Southampton School of MedicineDivision of Infection Inflammation&ImmunitySouthampton General HospitalSouthampton SO166YDUK MRC Immunochemistry Unit Department of BiochemistryUniversity of OxfordSouth Parks RoadOxford OX13QUUK

Surfactant proteins A(SP-A)and d(SP-d),both members of the collectin family,play a well established role in apoptotic cell recognition and *** in vitro data show that SP-A and SP-d interact with apoptotic neutrophils in a distinct ***-A and SP-d bind in a Ca^(2+)-dependent manner to viable and early apoptotic neutrophils whereas the much greater interaction with late apoptotic neutrophils is Ca^(2+)-*** surface molecules on the apoptotic target cells responsible for these interactions had not been identified and this study was done to find candidate target ***(MPO),a specific intracellular defense molecule of neutrophils that becomes exposed on the outside of the cell upon apoptosis,was identified by affinity purification,mass-spectrometry and western blotting as a novel binding molecule for SP-A and *** confirm its role in recognition,it was shown that purified immobilised MPO binds SP-A and SP-d,and that MPO is surface-exposed on late apoptotic ***-A and SP-d inhibit binding of an anti-MPO monoclonal Ab to late apoptotic *** microscopy confirmed that anti-MPO mAb and SP-A/SP-d colocalise on late apoptotic *** was identified as a further potential ligand for SP-A,and neutrophil defensin as a target for both proteins.

关键词： SP-A SP-d myeloperoxidase neutrophils flow cytometry mass spectrometry

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