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Role of gastrin-peptides in Barrett's and colorectal carcinogenesis

World Journal of Gastroenterology 2012年第45期18卷 6560-6570页

作者： Eduardo Chueca Angel Lanas elena Piazuelo IIS Aragon Aragon Institute of Health Sciences50009 ZaragozaSpain Networked Biomedical Research Center Hepatic and Digestive Diseases(CIBERehd) C/Corcega 180 bajos dcha08036 BarcelonaSpain Department of Medicine Psychiatry and DermatologyMedical University of ZaragozaC/Domingo Miral50009 ZaragozaSpain Service of Gastroenterology Hospital Clinico UniversitarioAvda.San Juan Bosco 1550009 ZaragozaSpain

Gastrin is the main hormone responsible for the stimulation of gastric acid secretion;in addition,gastrin and its derivatives exert proliferative and antiapoptotic effects on several cell *** synthesis and secretion are increased in certain situations,for example,when proton pump inhibitors are *** impact of sustained hypergastrinemia is currently being *** vitro experiments and animal models have shown that prolonged hypergastrinemia may be related with higher cancer rates;although,this relationship is less clear in human *** gastrin levels have been shown to cause hyperplasia of several cell types;yet,the risk for developing cancer seems to be the same in normo-and hypergastrinemic *** tumors also produce their own gastrin,which can act in an autocrine manner promoting tumor *** cancers are extremely dependent on gastrin to *** research focused only on the effects of amidated gastrins,but there has been an interest in intermediates of gastrin in the last few *** intermediates aren't biologically inactive;in fact,they may exert greater effects on proliferation and apoptosis than the completely processed *** certain gastrin overproduction states,they are the most abundant gastrin peptides *** purpose of this review is to examine the gastrin biosynthesis process and to summarize the results from different studies evaluating the production,levels,and effects of the main forms of gastrin in different overexpression states and their possible relationship with Barrett's and colorectal carcinogenesis.

关键词： Gastrin Progastrin Glycine-extended gas-trins C-terminal flanking peptide Hypergastrinemia,Proton pump inhibitors Colorectal cancer Esophagealadenocarcinoma Barrett's esophagus

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The research works of Coulomb and Amontons and generalized laws of friction

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Friction 2015年第2期3卷 183-190页

作者： elena POPOVA Valentin L.POPOV Institute of Mechanics Technische Universität Berlin10623Berlin National Research Tomsk State University 634050 TomskRussia

The paper is devoted to the contributions of Coulomb and Amontons to the physics of friction from the viewpoint of current discussions and attempts to formulate generalized laws of friction.

关键词： static friction sliding friction kinetics of friction material dependency history of science

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Development of Composite Cellular Cores for Sandwich Panels Based on Folded Polar Quadra-Structures

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第5期33卷 519-528页

作者： Valelltin Khaliulin Wang Zhijin elena Gershtein kazan national research technical university named after a.n.tupolev Kazan 120111.Russia minister key discipline laboratory of advanced design technology of aircraft nanjing university of aeronautics and astronauticsNanjing 210016P.R.China

An idea to develop a family of cellular cores for sandwich panels using a technology of prepreg folding is presented. Polar folded quadra structures are regarded as a geometric basis for these cores whose standard frag ment has lhe fourlh degree of axial symmelry. The classification of the polar strucluresaredeseribedanda method of various quadra slrueture synthesis is developed. A possibilily to provide high strength of lhe structure due m preservation of faces reinforcement pattern is presented. Arrangemen! of the plane core on a bi curvature surface is also introduced. Besides, provision of isotropyof the core in two or three directions are described. Finally, exam ples of cellular folded cores manufaclured from basalt reinforced plaslic are demonslrated.

关键词： composite sandwich panel cellular core folded polar quadra-structure synthesis of cellular struclure,quadra-struclure classification

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Impact of air drought on photosynthesis efficiency of the Siberian crabapple(Malus baccata L. Borkh.) in the forest-steppe zone of Transbaikalia, Russia

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Journal of Arid Land 2019年第2期11卷 255-266页

作者： Alexandr RUDIKOVSKII elena RUDIKOVSKAYA Lyubov DUDAREVA Siberian Institute of Plant Physiology and Biochemistry of Siberian Branch Russian Academy of Sciences

The adaption of photosynthesis, being a key metabolic process, plays an important role in plant resistance to air drought. In this study, the Siberian crabapple(Malus baccata L. Borkh.) in the forest-steppe zone of Transbaikalia region, Russia, was subjected to air drought stress and its photosynthesis characteristics were analyzed. The results show that air drought and sufficient soil moisture supply lead to the decrease in the total chlorophyll(Chl) content, while the ratio of Chls to carotenoids is constant in the Siberian crabapple tree. The function of photosystem II(PS-II) in the crabapple trees is characterized by a decrease in the fraction of absorbed light energy spent on the photochemical work and an increase in the proportion of non-photosynthetic thermal quenching. These changes indicate the photosynthetic down-regulation that acts as a universal photoprotective mechanism. During the midday hours, the combination of high air temperature and low air humidity leads to the decrease in the maximum photochemical quantum yield of photosystem II(Fv/Fm) and the efficiency of photosynthesis(PABS). The parameters of leaf gas exchange show the significant differences in these values between the control and experimental variants. During the morning hours, the Siberian crabapple, growing in the Irkutsk City,assimilates carbon dioxide more intensively. Due to the higher air humidity, the stomata are kept open and the necessary amount of carbon dioxide entries the sites of carboxylation. The low air humidity combined with wind in the experimental variants leads to the unreasonably high water loss in the crabapple leaves by more than 27% as compared to the control variant(Irkutsk City). However, water use efficiency in the morning hours increases during plant photosynthetic processes, i.e., 42% higher than that of control. This,apparently, is a reflection of the adaptation processes of the Siberian crabapple to the air drought and parching wind.

关键词： air drought chlorophyll fluorescence leaf gas exchange pigments water use efficiency

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Methyl acetate-methanol mixture separation by extractive distillation:Economic aspects

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 670-682页

作者： elena Graczova Branislav Sulgan Samuel Barabas Pavoi Steltenpohl Institute of Chemical and Environmental Engineering Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava81237 BratislavaSlovakia

Methyl acetate is considered low toxicity volatile solvent produced either as a by-product during methanol carbonylation or via acetic acid esterification with methanol. In both cases, pure methyl acetate has to be isolated from the reaction mixture. Simulation of methyl acetate separation from its mixture with methanol by extraction distillation was carried out in ASPEN + software. In total three case studies were assumed using two different extraction solvents and two solvent regeneration strategies. In case A, novel extraction solvent 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid, was considered. Raw material separation was achieved in an extraction distillation column while the solvent regeneration was accomplished in a second distillation column in this case. In case study B, the same extraction solvent was used; however, its regeneration was carried out in a single-effect evaporator. Dimethyl sulfoxide was the second extraction solvent selected. Its use in methyl acetate-methanol separation is presented in case study C. As high purity of dimethyl sulfoxide was required for the methyl acetate-methanol azeotrope breaking, its regeneration was carried out in the second distillation column only. To simulate the ternary methyl acetate–methanol–extraction solvent mixtures separation, vapor–liquid equilibrium was predicted based on the NRTL equation. Further, unknown properties of the considered ionic liquid and variation of these properties with temperature were predicted and introduced into the ASPEN + components properties database. Based on these data, optimum operation parameters of the respective separation equipment were established. In all case studies, the same condition had to be fulfilled, namely minimum methyl acetate content in the distillate from the extraction distillation column of 99.5mol-%. Results of simulations using the respective optimum operation parameters were employed in the economic evaluation of the three separation un

关键词： methyl acetate 1-ethyl-3-methylimidazolium trifluoromethanesulfonate extraction distillation dimethyl sulfoxide economic evaluation

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On-surface synthesis of covalent coordination polymers on micrometer scale

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Nano Research 2017年第3期10卷 933-940页

作者： Mathieu Koudia elena Nardi Olivier Siri Mathieu Abel Aix Marseille UniversitY CNRS IM2NP UMR 7334 13397 Marseille France Aix Marseille UniversitY CNRS CINaM UMR 7325 13288 Marseille France

On-surface synthesis under ultrahigh vacuum provides a promising strategy to control matter at the atomic level, with important implications for the design of new two-dimensional materials having remarkable electronic, magnetic, or catalytic properties. This strategy must address the problem of limited extension of the domains due to the irreversible nature of covalent bonds, which prevents the ripening of defects. We show here that extended materials can be produced by a controlled co-deposition process. In particular, co-deposition of quinoid zwitterion molecules with iron atoms on a Ag（111） surface held at 570 K allows the formation of micrometer-sized domains based on covalent coordination bonds. This work opens up the construction of micrometer-scale single-layer covalent coordination materials under vacuum conditions.

关键词： on-surface synthesis scanning tunnelingmicroscopy (STM) two-dimensional polymer covalent organic frameworks

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Ozone pollution threatens bird populations to collapse:an imminent ecological threat?

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Journal of Forestry Research 2023年第6期34卷 1653-1656页

作者： Evgenios Agathokleous Pierre Sicard Zhaozhong Feng elena Paoletti School of Applied Meteorology Nanjing University of Information Science&Technology(NUIST)Nanjing 210044People’s Republic of China ARGANS Sophia AntipolisFrance IRET-CNR Via Madonna del Piano 1050019 Sesto FiorentinoItaly

While bird populations are declining,the factors associated with this decline are *** on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff ecting bird ***,studies employing an epidemiological approach have reported signifi cant declines in avian populations in Central Europe and the United States due to air pollution,and ozone in *** advocate that urgent actions are needed to mitigate these eff ects,which threaten biodiversity and environmental health,and propose a series of measures which can enlighten the path toward mitigating air pollution eff ects on avian populations.

关键词： Air pollution Biosecurity Bird population Biodiversity Ornithology Ozone risk

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Bleeding with the artificial heart: Gastrointestinal hemorrhage in CF-LVAD patients

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World Journal of Gastroenterology 2017年第22期23卷 3945-3953页

作者： Grigoriy E Gurvits elena Fradkov Division of Gastroenterology New York University School of Medicine/Langone Medical Center Department of Medicine New York University School of Medicine/Langone Medical Center

Continuous-flow left ventricular assist devices(CF-LVADs)have significantly improved outcomes for patients with end-stage heart failure when used as a bridge to cardiac transplantation or,more recently,as destination ***,its implantations carries a risk of complications including infection,device malfunction,arrhythmias,right ventricular failure,thromboembolic disease,postoperative and nonsurgical bleeding.A significant number of left ventricular assist devices(LVAD)recipients may experience recurrent gastrointestinal hemorrhage,mainly due to combination of antiplatelet and vitamin K antagonist therapy,activation of fibrinolytic pathway,acquired von Willebrand factor deficiency,and tendency to develop small intestinal angiodysplasias due to increased rotary speed of the *** bleeding in LVAD patients remains a source of increased morbidity including the need for blood transfusions,extended hospital stays,multiple readmissions,and overall *** of gastrointestinal bleeding in LVAD patients involves multidisciplinary approach in stabilizing the patients,addressing risk factors and performing structured endoluminal evaluation with focus on upper gastrointestinal tract including jejunum to find and eradicate culprit *** and procedural intervention is largely successful and universal bleeding cessation occurs in transplanted patients.

关键词： Gastrointestinal bleeding Left ventricular assist devices Heart failure Angioectasia Endoscopy

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GREEN STAR—LEED’S AUSTRALIAN COUSIN

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Journal of Green Building 2007年第3期2卷 32-40页

作者： elena Bondareva Green Building Council of Australia

INTRODUCTION Within the global green building family,if one likens the US and the Australian Green Building Councils to siblings,Green Star and LEED can be viewed as *** sharing much of the same conceptual“genome,”they are appropriately different because they have“grown up”in different“families”and reflect unique sets of aspirations,influences,and *** in 2002,the Green Building Council of Australia(GBCA)is a dynamic not-for-profit organisation that is uniquely supported by all sectors of the industry(including Australia’s largest and most influential building owners,developers,and contractors),as well as all levels of government,academia,and non-government(NGO)*** GBCA was created with a mission to transition the property industry towards sustainability and drive the uptake of green building practices across *** GBCA achieves this,and grows a strong green platform to support both the local and international green building movement,through its environmental rating system for buildings,Green Star,as well as through its educational and knowledge-transfer activities,advocacy work,and research.

关键词： LEED Australia uniquely

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Unsettled Territories: Ruins and Cities in Chinese Contemporary Landscape Representation

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2019年第1期13卷 25-48页

作者： elena Macri Independent Scholar

In his book Time in Ruins, the French anthropologist Marc Auge pointed out that Hhumanity is not in ruins, it is being built." These words well fit both the present-day Chinese context and the figurative trend of new shanshuihua in which construction sites, cityscapes and artificial nature territories become the subject of depiction. New iconic elements that provide a visual and conceptual framework for artists' construction of a different shanshui-type heavily indebted to Chinese social and environmental changes, these new coded depictions substitute the traditional representation of natural landscape, reflect the rise of a new sensibility about nature and challenge the idea of what landscape is in the context of Chinese contemporary art. By focusing on a variety of works related to the theme of art讦icial nature and representing paradigmatic images of physical and allegorical landscape, this paper aims to explore this visual and conceptual innovations introduced in the context of new shanshuihua and analyze the way in which artists use nature, trying to find a new aesthetic categorization for this artistic genre.

关键词： Chinese contemporary art new shanshuihua ecocriticism ruins landscape

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