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A New Perspective of the Physical Processes Associated with the Clear-Sky Greenhouse Effect over High Latitudes

Advances in Atmospheric Sciences 2004年第2期21卷 171-180页

作者： Zuohao ca0 Ronald E．STEWART M．K．YAU MeteorologicalServiceofcanada，Ontario，canada DepartmentofAtmosphericandOceanicSciences，McGillUniversityMontreal，Quebec，canada

The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model MODTRAN3 (Moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.

关键词： greenhouse effect surface ernissivity physical processe high latitude seasonal variation

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ca19-9 antigen levels can distinguish between benign and malignant pancreaticobiliary disease

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 620-626页

作者： Gareth Morris-Stiff Mary Teli Nicky Jardine Malcolm ca Puntis Department of Surgery University Hospital of Wales

BACKGROUND:ca19-9 is a carbohydrate tumor-associated antigen which is frequently upregulated in pancreatobiliary ***,it may also be elevated in patients with jaundice in the absence of a tumor due to biliary obstruction,and in other non-hepato-pancreatico-biliary *** study aimed to evaluate whether ca19-9 levels could accurately differentiate between benign and malignant pancreatobiliary ***:All patients referred to a single surgeon for investigation of pancreaticobiliary disease in 2003 in whom a firm diagnosis had been established were *** malignant disease,a histological diagnosis was required but for benign disease a firm radiological diagnosis was deemed *** patients were divided into 4 categories:pancreatic adenocarcinoma(Pca);cholangiocarcinoma(Cca);chronic pancreatitis(CP)and biliary calculous disease(calc).Bilirubin and alkaline phosphatase levels corresponding to the point of assessment of ca19-9 were also ***:Final diagnoses were made of pancreatic adenocarcinoma(Pca,n=73),cholangiocarcinoma(Cca,n=19),ampullary carcinoma(Amp,n=7),neuroendocrine carcinoma(Neu,n=4),duodenal carcinoma(Duo,n=3),chronic pancreatitis(CP,n=115),and biliary calculous disease(calc,n=27).Median ca19-9 levels(U/ml)were:Pca,653;Cca,408;Duo,403;calc,27;CP,19;Neu,10.5;Amp,8(reference range:0-37).The ca19-9 levels were significantly greater for malignant than for benign disease,could differentiate Pca from Cca/Duo,and were significantly higher in unresectable than in resectable *** sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)for ca19-9 were 84.9%,69.7%,67.7%and 86.1%,respectively.A ROC analysis provided an area under the curve for ca19-9 of 0.871(0.820-0.922),giving an optimal ca19-9 of 70.5 U/ml for differentiating benign from malignant *** this cut-off,the sensitivity was 82.1%,while specificity,PPV and NPV improved to 85.9%,81.3%and 86.5%,*** sta

关键词： ca19-9 antigen pancreatic disease biliary tract disease malignant benign

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Representations of Knot Groups and Twisted Alexander Polynomials

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Acta Mathematica Sinica,English Series 2001年第3期17卷 5+362-380页

作者： Xiao Song LIN Department of Mathematics,University of california,Riversides,ca 92521.USA Department of Mathematics University of California Riverside USA

We present a twisted version of the Alexander polynomial associated with a matrix rep- resentation of the knot *** of two knots with the same Alexander module but different twisted Alexander polynomials are given.

关键词： Twisted Alexander polynomial Representation space Knot group

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Non-optical polyp-based resect and discard strategy:A prospective clinical study

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World Journal of Gastroenterology 2022年第19期28卷 2137-2147页

作者： Mahsa Taghiakbari celia Hammar Mira Frenn Roupen Djinbachian Heiko Pohl Erik Deslandres Simon Bouchard Mickael Bouin Daniel von Renteln Department of Gastroenterology Montreal University Hospital Research Center(CRCHUM)Montréal H2X 0A9QuebecCanada Department of Gastroenterology University of MontrealFaculty of MedicineMontreal H2X 0A9QuebceCanada Department of Internal Medicine University of Montreal Hospital Center(CHUM)Montreal H2X 0A9QuebecCanada Department of Medicine Veterans Affairs Medical CenterWhite River JunctionVT 05009United States Department of Gastroenterology Dartmouth Geisel School of Medicine and The Dartmouth InstituteHanoverNH 03755United States

BACKGROUND Post-polypectomy surveillance intervals are currently determined based on pathology *** To evaluate a polyp-based resect and discard model that assigns surveillance intervals based solely on polyp number and *** Patients undergoing elective colonoscopies at the Montreal University Medical Center were enrolled *** polyp-based strategy was used to assign the next surveillance interval using polyp size and *** intervals were also assigned using optical diagnosis for small polyps(cal diagnosis,and the pathology-based reference standard using the 2020 United States Multi-Society Task Force *** outcomes included the proportion of reduction in required histopathology evaluations and proportion of immediate post-colonoscopy recommendations provided to *** Of 944 patients(mean age 62.6 years,49.3%male,933 polyps)were *** surveillance interval agreement for the polyp-based strategy was 98.0%[95%confidence interval(CI):0.97-0.99]compared with pathology-based *** diagnosis-based intervals achieved 95.8%(95%CI:0.94-0.97)agreement with *** using the polyp-based strategy and optical diagnosis,the need for pathology assessment was reduced by 87.8%and 70.6%,*** polyp-based strategy provided 93.7%of patients with immediate surveillance interval recommendations vs 76.1%for optical *** The polyp-based strategy achieved almost perfect surveillance interval agreement compared with pathology-based assignments,significantly reduced the number of required pathology evaluations,and provided most patients with immediate surveillance interval recommendations.

关键词： Colonoscopy Colorectal pathology Colorectal adenomas Endoscopy Surveillance Optical diagnosis

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ON THE KINEMATIC GEOMETRY OF MANY BODY SYSTEMS

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 11-28页

作者： WU-YI HSIANG(Department of Mathematics,University of caLIFORNIA,berkeley,ca 94720-3840,USA) Department of Mathematics University of California Berkeley CA 94720-3840 USA

In mechanics, both classical and quantum, one studies the profound interaction betweentwo types of energy, namely, the kinetic energy and the potential energy. The former can beorganized as the kinematic metric on the configuration space while the latter can be representedby a suitable potential function, such as the Newtonian potential in celestial mechanics andthe Coulomb potential in quantum mechanics of atomic and molecular physics. In this paper,the author studies the kinematic geometry of n-body systems. The main results are (i) theintroduction of a canonical coordinate svstem which reveals the total amount of kinematicsymmetry by an SO(3) x O(n-1) action in such a canonical coordinate representationt (ii) anin depth analysis of the above kinematic system both in the setting of classical invariant theoryand by the technique of equivariant Riemannian geometry; (iii) a remarkably simple formulafor the potential function in such a canonical coordinate system which reveals the well-fittingbetween the kinematic symmetry and the Potential energy.

关键词： Kinematic geometry Many body system Configuration space

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基于岩土介质三维孔隙结构的两相流模型

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岩土工程学报 2020年第1期42卷 37-45页

作者：张鹏伟胡黎明 Jay N Meegoda Michael A celia 清华大学水沙科学与水利水电工程国家重点实验室北京100084 北京交通大学北京100044 新泽西理工学院美国07102 普林斯顿大学美国08544

地下储层中岩土介质一般具有较低的孔隙连通性,宏观流动模拟一般忽略微观尺度的孔隙连通性,通过渗透率、弯曲度等参数反映储层的整体特性。但岩土介质的多孔性及孔隙间复杂的连通性,使得宏观描述流体在岩土介质中流动不能反映其内在流... 详细信息

地下储层中岩土介质一般具有较低的孔隙连通性,宏观流动模拟一般忽略微观尺度的孔隙连通性,通过渗透率、弯曲度等参数反映储层的整体特性。但岩土介质的多孔性及孔隙间复杂的连通性,使得宏观描述流体在岩土介质中流动不能反映其内在流动特征。孔隙结构模型的建立可以反映岩土介质中孔隙的几何形态及空间连通性,为解释流体在复杂多孔介质中的流动特性提供有效手段。通过考虑岩土介质孔隙尺寸分布、孔隙孔喉空间相关性、孔隙连通性等特征参数,建立了反映不同岩土介质连通性、各向异性特征的等效孔隙网络模型。等效孔隙网络模型通过水力特征参数等效的方式反映岩土介质三维微观孔隙结构,通过渗透率计算验证了模型的有效性。此外,基于建立的孔隙结构模型,开发了孔隙尺度动态两相流计算模型,模型可以反映孔隙内弯液面的动态运动过程,直观反映多孔介质中的优势渗流,可以为不同孔隙尺度岩土介质提供表观渗透率、击穿曲线、相对渗透率曲线等宏观计算参数。将孔隙尺度两相流模型应用于页岩气开采中水力阻滞特性研究,结果表明:页岩基质的残余饱和度约为30%,随着平均配位数的增加,残余饱和度显著降低。

关键词：两相流等效孔隙网络模型相对渗透率页岩气优势渗流

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Autophagy is increased in cryptorchid testis resulting in abnormal spermatozoa

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Asian Journal of Andrology 2019年第6期21卷 570-576页

作者： Marina G Yefimova Antoine Buschiazzo Agnes Burel Marie-Therese Lavault Celine Pimentel Guilhem Jouve Sylvie Jaillard Bernard Jegou Nicolas Bourmeyster celia Ravel Univ Rennes CHU RennesLaboratoire de Biologie de la Reproduction-CECOSInsermEH ESPIrset(Institut de recherche en santeenvironnement et travail)-UMR_S 1085Rennes F-35000France Sechenov Institute of Evolutionary Physiology and Biochemistry Russian Academy of Sciences194223 St-PetersburgRussia Univ Rennes Biosit Platform-MRICRennes 35000France Univ Rennes CHU RennesDepartment of Gynecology Obstetric and Human ReproductionRennes 35000France Univ Rennes CHU RennesDepartment of CytogeneticIrset(Institute for Environmental and Occupational Health)-UMR_S 1085Rennes 35000France Univ Rennes InsermEH ESPIrset(Institute for Environmental and Occupational Health)-UMR_S 1085Rennes F-35000France University of Poitiers-CHU Poitiers STIM ERL 7003 CNRSPoitiers 86021France

Autophagy is invoIved in spermatogenesis by regulating germ cell *** catabolic process increases with hyperthermic conditions to prevent the accumulation of damaged *** is associated with impairment of germ cell maturation revealed by the presence of immature forms of sperm cells in *** aim of the present study was to evaluate the status of autophagy in sperm cells from cryptorchid *** samples of cryptorchid patients and normozoospermic controls were analyzed by immuno cytochemistry and electron *** protei ns,autophagy-related protein 9(ATG9)and microtubule-associated protein,lA/lB-light chain 3(LC3)were localized by immunocytochemistry on the acrosome and on the equatorial segment of sperm ***3 was also detected in the midpiece of cryptorchid sperm *** substrate p62 protein was present in the acrosome and in the postequatorial segment of sperm in control samples,but not in the cryptorchid *** electron microscopy revealed double-membrane-limited autophagosomes in postequatorial part of spermatozoa head and midpiece in cryptorchid *** degraded mitochondria were frequently discerned in autophagic *** conclusion,autophagy is increased in sperm cells from patients with cryptorchid history comparatively to *** work provides insights into the role of autophagy in the maturation and survival of human male gametes in pathological ***,regulating autophagy could represent a potential way to improve sperm quality in cryptorchid men.

关键词： autophagy cryptorchidism mitophagy spermatozoa

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Molecular and phylogenetic characterization of South African H5N2 strains affecting ostriches

Molecular and phylogenetic characterization of South African...

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The 15th World Veterinary Poultry Congress

作者： celia Abolnik ARC-Onderstepoort Veterinary Institute Private Bag X5Onderstepoort Pretoria0110South Africa

＜正＞Introduction In 2004 South Africa recorded its first outbreak of highly pathogenic notifiable avian influenza （HPNAI）in forty three years when an H5N2 strain caused mortalities in ostrich flocks of the Eastern cape *** an eradication program that was followed by intensive surveillance,South Africa officially

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The Role of the Pharmacist in Pre-Exposure Prophylaxis

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Pharmacology & Pharmacy 2014年第3期5卷 225-228页

作者： celia Moffat Joel Matyanga Pharmaceutical Technology Department Harare Institute of Technology Harare Zimbabwe

Pre-exposure prophylaxis is a new HIV prevention method that has shown to be effective in HIV uninfected persons at very high risk of HIV infection. It involves daily use of truvada in combination with other proven methods of HIV prevention. The aim of this paper is to discuss the various roles that pharmacists play in pre-exposure prophylaxis to maximize therapy.

关键词： HIV PrEP Role Pharmacist

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Recent Advances in Superplastic Intermetallics

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 405-417页

作者： NIEH Tai-Gang WADSWORTH Jeffrey (Lawrence Livermore National Laboratory, Livermore, ca 94550, USA) Lawrence Livermore National Lab Livermore United States

Superplasticity in intermetallic alloys is reviewed. Intermetallics which have been demonstrated to be superplastic include nickel-based (Ni_3Al, Ni_3Si), titanium-base (Ti_3Al, TiAl), and iron-base (Fe_3Al, FeAl) alloys. These alloys are primarily finegrained, two phase materials. But, superplasticity was also observed in some iron-base alloys which were in coarsegrained conditions. These alloys behave like Class I solid solution. The superplastic deformation mechanisms as well as microstructural characteristics are discussed. The superplastic forming of intermetallics is also briefly addressed.

关键词： Superplasticity microstructure grain size boundary sliding

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