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Pancreatitis and pancreatic cancer:A case of the chicken or the egg

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World j.urnal of Gastroenterology 2021年第23期27卷 3148-3157页

作者： Devica S Umans Sanne A Hoogenboom Noor j.Sissingh Selma j.Lekkerkerker robert C Verdonk j.anin E van Hooft Department of Gastroenterology and Hepatology Amsterdam Gastroenterology and MetabolismAmsterdam UMCAmsterdam 1105 AZThe Netherlands Department of Research and Development St.Antonius HospitalNieuwegein 3430 EMThe Netherlands Department of Gastroenterology and Hepatology Leiden University Medical CenterLeiden 2333 ZAThe Netherlands Department of Gastroenterology and Hepatology St.Antonius HospitalNieuwegein 3430 EMThe Netherlands

Acute pancreatitis(AP),chronic pancreatitis(CP)and pancreatic cancer are three distinct pancreatic diseases with different prognoses and treatment ***,it may be difficult to differentiate between benign and malignant *** may be a first symptom of pancreatic cancer,particularly in patients between the ages of 56 and 75 with presumed idiopathic AP who had a concomitant diagnosis of new-onset diabetes mellitus or patients who present with CP at diagnosis of *** these patients,additional imaging is warranted,preferably by endoscopic *** may lead to pancreatic cancer through oncogenic mutations,mostly in patients with hereditary CP,and in patients in whom risk factors for pancreatic cancer(e.g.,nicotine and alcohol abuse)are also *** with PRSS1-mediated CP and patients with a history of autosomal dominant hereditary CP without known genetic mutations may be considered for surveillance for pancreatic *** inflammation may mimic pancreatic cancer by appearing as a focal mass-forming lesion on *** between the above mentioned benign and malignant disease may be facilitated by specific features like the duct-penetrating sign and the duct-to-parenchyma *** efforts are aimed towards developing a superior discriminant between pancreatitis and pancreatic cancer in the form of imaging modalities or *** may aid clinicians in timely diagnosing pancreatic cancer in a potentially curable stage.

关键词： Pancreatic diseases Pancreatic neoplasms Pancreatitis Pancreas Chronic Pancreatitis Exocrine pancreatic

The Orosirian(1800–2050 Ma)plate tectonic episode:Key for reconstructing the Proterozoic tectonic record

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Geoscience Frontiers 2023年第3期14卷 1-9页

作者： robert j.Stern Geosciences Dept. U Texas at DallasRichardsonTX 75083-0688United States

Eight lines of evidence indicate that the Orosirian Period in mid-Paleoproterozoic time was characterized by plate tectonics:ophiolites,low T/P metamorphism including eclogites,passive margin formation,tall mountains,paleomagnetic constraints,ore deposits,abundant S-type granites,and seismic images of paleo-subduction *** plate tectonic episode occurred about 1 billion years earlier than the present plate tectonic episode began in Neoproterozoic *** two plate tectonic episodes bracket the‘Boring Billion’,which may have been a protracted single lid tectonic episode that began when the supercontinent Nuna or Columbia *** of multiple lines of evidence for Orosirian plate tectonics demonstrates that Earth’s tectonic style can be reconstructed with some confidence back to at least Early Paleoproterozoic time,and thus the absence of compelling evidence for Mesoproterozoic plate tectonics is not obvious due to poor preservation.A tectono-magmatic lull2.3 Ga suggests an earlier episode of single lid *** for two episodes of plate tectonics and two episodes of single lid tectonics indicates that Earth switched between single lid and plate tectonics multiple times during the last 2.4 Ga.

关键词： Plate tectonics Single lid tectonics Urey ratio Paleoproterozoic

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.j.Hubbard O.Hetherington D.j.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Differences in sensitivity of native and exotic fish species to changes in river temperature

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Current Zoology 2011年第6期57卷 852-862页

作者： R.S.E.W. LEUVEN A.j. HENDRIKS M.A.j. HUIj.REGTS H.j.R. LENDERS j. MATTHEWS van DER VELDE Radboud University Nij.egen Institute for Water and Wetland Research Department of Environmental Science Heyendaal- seweg 135 NL-6525 AJ Nijmegen The Netherlands Radboud University Nij.egen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 NL-2300 RA Leiden The Netherlands

This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the Rhine-Main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the Rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river Rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions

关键词： Aquatic invaders Global warming Heat discharges Lethal temperature River Rhine Thermal heterogeneity

Hydrothermal Processes in the Solar System：A Review

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地质科技情报 2008年第1期27卷 1-12页

作者： Franco PIRAj.O Martin j. van KRANENDONK Long XIAO Geological Survey of Western Australia 100 Plain Street Perth WA 6004 Australia Research Center forSpace Science ＆ Technology Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

最近美国航空与空间计划署(NASA)开展的卡西尼—惠更斯外空探测计划发现,在直径为500km的卫星——土卫二上存在水冰和间隙泉的喷发活动。这一现象和在火星上工作的"机遇号"和"勇气号"漫游车所发现的液态水一起,证明了除地球以外的其他... 详细信息

最近美国航空与空间计划署(NASA)开展的卡西尼—惠更斯外空探测计划发现,在直径为500km的卫星——土卫二上存在水冰和间隙泉的喷发活动。这一现象和在火星上工作的"机遇号"和"勇气号"漫游车所发现的液态水一起,证明了除地球以外的其他星球上过去和现在都存在水,其中的一些星体还有火山活动的证据,这意味着这些星球上可能存在过热液活动地质过程。讨论了火星、木卫二和土卫二可能存在的热液系统类型。这些热液系统类型是根据地球上的构造背景进行相似性研究后得出的,例如海底、火山和裂谷系统。将东非裂谷和贝加尔湖裂谷系统与火星Tharsis高原上巨大的水手大峡谷进行了对比,这些地区都是由地幔柱作用下构造—热液活动导致的地壳抬升、火山和裂谷作用。在火星上,地下冰或低温层会在火山活动和(或)小行星或彗星撞击作用下溶解而形成热液对流。

关键词：热液活动过程火星木卫二土卫二

X-ray Multiple Diffraction Topographic Imaging Technique For Growth History Study of Habit Modifying Impurity Doped Crystals

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Chemical Research in Chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA C. K. j. robert M. C. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification Crystal growth Growth defects

Development of a multivariate empirical model for predicting weak rock mass modulus

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International j.urnal of Mining Science and Technology 2015年第4期25卷 545-552页

作者： Kallu Raj.R. Keffeler Evan R. Watters robert j. Agharazi Alireza Department of Mining Engineering University of Nevada RESPEC Consulting and Services University of Nevada Itasca Houston Inc.

Estimating weak rock mass modulus has historically proven difficult although this mechanical property is an important input to many types of geotechnical analyses. An empirical database of weak rock mass modulus with associated detailed geotechnical parameters was assembled from plate loading tests per- formed at underground mines in Nevada, the Bakhtiary Dam proj.ct, and Portugues Dam proj.ct. The database was used to assess the accuracy of published single-variate models and to develop a multivari- ate model for predicting in-situ weak rock mass modulus when limited geoteehnical data are available. Only two of the published models were adequate for predicting modulus of weak rock masses over lim- ited ranges of alteration intensities, and none of the models provided good estimates of modulus over a range of geotechnical properties. In light of this shortcoming, a multivariate model was developed from the weak rock mass modulus dataset, and the new model is exponential in form and has the following independent variables：（1） average block size or j.int spacing, （2） field estimated rock strength, （3） dis- continuity roughness, and （4） discontinuity infilling hardness. The multivariate model provided better estimates of modulus for both hard-blocky rock masses and intensely-altered rock masses.

关键词： In-situ modulus Weak rock mass Preliminary design Elastic deformation

Plant Carbonic Anhydrases： Structures, Locations, Evolution, and Physiological Roles

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Molecular Plant 2017年第1期10卷 30-46页

作者： robert j. DiMario Harmony Clayton Ananya Mukhedee Martha Ludwig j.mes V. Moroney Department of Biological Sciences Louisiana State University Baton Rouge LA 70803 USA School of Chemistry and Biochemistry University of Western Australia Perth WA 6009 Australia

Carbonic anhydrases （CAs） are zinc metalloenzymes that catalyze the interconversion of CO2 and HCO3- and are ubiquitous in nature. Higher plants contain three evolutionarily distinct CA families, αCAs, 13CAs, and γCAs, where each family is represented by multiple isoforms in all species. Alternative splicing of CA transcripts appears common; consequently, the number of functional CA isoforms in a species may exceed the number of genes. CAs are expressed in numerous plant tissues and in different cellular locations. The most prevalent CAs are those in the chloroplast, cytosol, and mitochondria. This diversity in location is paralleled in the many physiological and biochemical roles that CAs play in plants. In this review, the number and types of CAs in C3, C4, and crassulacean acid metabolism （CAM） plants are considered, and the roles of the α and yCAs are briefly discussed. The remainder of the review focuses on plant βCAs and includes the identification of homologs between species using phylogenetic approaches, a consideration of the inter- and intracellular localization of the proteins, along with the evidence for alternative splice forms. Current understanding of βCA tissue-specific expression patterns and what controls them are reviewed, and the physiological roles for which βCAs have been implicated are presented.

关键词： carbonic anhydrase regulation alternative splicing physiological role

DC/AC circuits and electronics : principles & applications /

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