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Tight junction disruption: Helicobacter pylori and dysregulation of the gastric mucosal barrier

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World Journal of Gastroenterology 2015年第40期21卷 11411-11427页

作者： Tyler J caron kathleen E Scott James G Fox Susan J Hagen Department of Surgery Beth Israel Deaconess Medical Center and Harvard Medical School Division of Comparative medicine Massachusetts Institute of Technology

Long-term chronic infection with Helicobacter pylori(H. pylori) is a risk factor for gastric cancer development. In the multi-step process that leads to gastric cancer,tight junction dysfunction is thought to occur and serve as a risk factor by permitting the permeation of luminal contents across an otherwise tight mucosa. mechanisms that regulate tight junction function and structure in the normal stomach,or dysfunction in the infected stomach,however,are largely unknown. Although conventional tight junction components are expressed in gastric epithelial cells,claudins regulate paracellular permeability and are likely the target of inflammation or H. pylori itself. There are 27 different claudin molecules,each with unique properties that render the mucosa an intact barrier that is permselective in a way that is consistent with cell physiology. Understanding the architecture of tight junctions in the normal stomach and then changes that occur during infection is important but challenging,because most of the reports that catalog claudin expression in gastric cancer pathogenesis are contradictory. Furthermore,the role of H. pylori virulence factors,such as cytotoxin-associated gene A and vacoulating cytotoxin,in regulating tight junction dysfunction during infection is inconsistent in different gastric cell lines and in vivo,likely because non-gastric epithelial cell cultures were initially used to unravel the details of their effects on the stomach. Hampering further study,as well,is the relative lack of cultured cell models that have tight junction claudins that are consistent with native tissues. This summary will review the current state of knowledge about gastric tight junctions,normally and in H. pylori infection,and make predictions about the consequences of claudin reorganization during H. pylori infection.

关键词： Helicobacter pylori Tight junction Claudins Parace

Evolution of IPv6 Internet topology with unusual sudden changes

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Chinese Physics B 2013年第7期22卷 602-609页

作者：艾均赵海 kathleen m. Carley 苏湛李辉 College of Information Science and Engineering Northeastern University Institute for Software Research Carnegie Mellon University

The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation. We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet. After evaluating the changes of average degree, average path length, and some other metrics over time, we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top–bottom connection enhancement the Internet maintains its efficiency with links largely decreased.

关键词： scale-free network Internet topology evolution unusual evolution of Internet topology complex network analysis

Predicting phosphorus sorption isotherm parameters in soil using data of routine laboratory tests

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Pedosphere 2021年第5期31卷 694-704页

作者： kathleen S.DUNNE Nicholas m.HOLDEN Karen DALY Teagasc Johnstown CastleEnvironmental Research CentreCo.Wexford Y35TC97(Ireland) UCD School of Biosystems and Food Engineering University College DublinBelfieldDublin 4 D04VIW8(Ireland)

Knowledge of phosphorus(P)sorption dynamics across different soil types could direct agronomic and environmental management of *** objective of this study was to predict P isotherm parameters for a national soil population using data of routine laboratory *** and Freundlich sorption parameters were calculated from two different ranges(0-25 and 0-50 mg P L^(-1))using an archive of representative agricultural soil types from *** linear regression(mLR)identified labile forms of aluminium(Al)and iron(Fe),organic matter(Om),cation exchange capacity(CEC),and clay as significant *** and Freundlich sorption capacities,Freundlich affinity constant,and Langmuir buffer capacity were predicted reliably,with R^(2) of independent validation>*** isotherm parameters were predicted from P sorbed at a single concentration of 50 mg P L^(-1)(S_(50)).An mLR prediction of P sorption maximum in the 0-50 mg P L-1 range was achieved,to an accurate standard,using S_(50),Om,and mehlich-3 Fe(R^(2) of independent calibration and validation being 0.91 and 0.95,respectively).Using Giles’four shapes of isotherms(C,L,H,and S),L non-strict-and C-shaped isotherm curves accounted for 64% and 27% of the soils,*** clustering identified a separation of isotherm curves influenced by two ranges of mehlich-3 *** with a low range of mehlich-3 Al(2.5-698 mg kg^(-1))had no incidence of rapid sorption(C shape).Single point indices,Al,or available soil data make the regression approach a feasible way of predicting Langmuir parameters that could be included with standard agronomic soil P testing.

关键词： available phosphorus binding fertilizer soil test sorption maximum

Numerical sensitivity analysis of welding-induced residual stress depending on variations in continuous cooling transformation behavior

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Frontiers of materials Science 2011年第2期5卷 168-178页

作者： C. HEINZE C. SCHWENK m. RETHmEIER J. caron Federal Institute for materials Research and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of continuous cooling transformation （CCT） diagrams in numerical welding simulations is state of the art. Nevertheless, specifications provide limits in chemical composition of materials which result in different CCT behavior and CCT diagrams, respectively. Therefore, it is necessary to analyze the influence of variations in CCT diagrams on the developing residual stresses. In the present paper, four CCT diagrams and their effect on numerical calculation of residual stresses are investigated for the widely used structural steel S355J2 ＋ N welded by the gas metal arc welding （GmAW） process. Rather than performing an arbitrary adjustment of CCT behavior, four justifiable data sets were used as input to the numerical calculation： data available in the Sysweld database, experimental data acquired through Gleeble dilatometry tests, and TTTICCT predictions calculated from the JmatPro and Edison Welding Institute （EWI） Virtual Joining Portal software. The performed numerical analyses resulted in noticeable deviations in residual stresses considering the different CCT diagrams. Furthermore, possibilities to improve the prediction of distortions and residual stress based on CCT behavior are discussed.

关键词： welding simulation GmAW CCT sensitivity welding residual stress

The Global Boundary Stratotype Section and Point （GSSP） for the base of the Cenomanian Stage, mont Risou, Hautes-Alpes, France

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Episodes 2004年第1期27卷 21-32页

作者： W.J.Kennedy A.S.Gale J.A.Lees m.caron OxfordUniversitymuseumofNaturalHistory ParksRoadOxfordOXI3PWU.K. DepartmentofPalaeontology TheNaturalHistoryMuseumCromwellRoadLondonSW75BPU.K.andSchoolofEarthandEnvironmentalSciencesUniversityofGreenwichChathamMaritimeCampusChathamKentME44AWU.K. ResearchSchoolofGeologicalandGeophysicalSciences BirkbeckCollegeandUniversityCollegeLondonGowerStreetLondonWCIE6BTU.K. InstitutdeGeologie UniversitedeFribourgCH-1700FribourgSwitzerland.

Following the unanimous recommendation of the International Commission on Stratigraphy, the Global boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage is defined at a level 36 metres below the top of the marnes Bleues Formation, a level that corresponds to the the first appearance of the planktonic foraminiferan Rotalipora globotruncanoides Sigal, 1948, on the south side of mont Risou, east of Rosans, Haute-Alpes, France, where it can be placed in the context of a series of secondary marker levels based on nannofossils, planktonic foraminifera, ammonites,and an ornate δ^13C curve.

关键词：地层学地层分界线层型地质构造

Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： kathleen m Kneeland Steven R. Skoda John E. Foster Department of Entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ARS-KBUSLIRL Screwworm Research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. Especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AmOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AmOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

p53 functional loss,stemness and hepatocellular carcinoma

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Hepatoma Research 2020年第11期6卷 67-84页

作者： Claude caron de Fromentel massimo Levrero Centre de Recherche en Cancérologie de Lyon INSERM U1052CNRS 5286UniversitéClaude Bernard Lyon 1Centre Léon BérardLyon 69008France Service d’Hépatologie et de Gastroentérologie Hôpital de la Croix-RousseHospices Civils de LyonLyon 69004France Dipartimento di Scienze Cliniche InternisticheAnestesiologiche e Cardiovascolari(SCIAC)Sapienza UniversityRome 00161Italy Center for Life Nano Science Istituto Italiano di TecnologiaSapienza UniversityRome 00161Italy

The tumor suppressor p53 is a key player in the control of genomic integrity and homeostasis in connection with p63 and p73,the two other members of the p53 *** of functional p53 leads to the proliferation and survival of mature cells and progenitor or stem cells that accumulate genetic alterations,thus favoring tumorigenesis.p53 loss of function,observed in a wide variety of human tumor types,is frequently caused by missense mutations more frequently found in the DNA binding domain,but can also be due to the expression of a plethora of viral and cellular negative *** hepatocellular carcinoma(HCC)represents a specific situation,first because the TP53 gene mutations pattern exhibits a“hot spot”rarely found in other tumor types that is linked to Aflatoxin B1 exposure and,second,because many HCCs do not exhibit any TP53 ***,we provide an overview of the current knowledge about the inhibition of p53 functions by the N-terminal(ΔN)truncated forms of the family,and their role in the emergence and maintenance of pre-malignant cells with stem cell characteristics and in HCC *** focus in particular on the Nanog-IGF1R-ΔNp73 axis that is associated with stem-like features in HCC cells and that may provide an attractive new therapeutic target and help to develop new biomarkers for HCC risk stratification,as well as preventive strategies.

关键词： p53 family p53 functional inactivation ΔNp73 hepatic progenitor cells cancer stem cells Nanog hepatocellular carcinoma

Experimental and modeling Study of Forest Fire Effect on Soil Thermal Conductivity

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Pedosphere 2016年第4期26卷 462-473页

作者： kathleen m.SmITS Elizabeth KIRBY William J.mASSmAN Larry Scott BAGGETT Center for the Experimental Study of Subsurface Environmental Processes Department of Civil and Environmental EngineeringColorado School of Mines USDA Forest Service Rocky Mountain Research Station

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited. The purpose of this study was to evaluate the long-term impact of fire on the effective thermal conductivity of soils by directly comparing fire-heated and no-fire control soils through a series of laboratory studies. The thermal conductivity was measured for ten soil samples from two sites within the manitou Experimental Forest, Colorado, USA, for a range of water contents from saturation to the residual degree of saturation. The thermal conductivity measured was compared with independent estimates made using three empirical models from literature, including the Campbell et al. （1994）, CSt~ and Konrad （2005）, and massman et al. （2008） models. Results demonstrate that for the test soils studied, the thermal conductivity of the fire-heated soils was slightly lower than that of the control soils for all observed water contents. modeling results show that the Campbell et al. （1994） model gave the best agreement over the full range of water contents when proper fitting parameters were employed. Further studies are needed to evaluate the significance of including the influence of fire burn on the thermal properties of soils in modeling studies.

关键词： controlled burn degree of saturation empirical model water content wildfire

management of vascular complications following calcium hydroxylapatite filler injections:a systemic review of cases and experimental studies

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Plastic and Aesthetic Research 2022年第1期9卷 503-528页

作者： Aleksandra L.Lindgren kathleen m.Welsh University of Queensland-Ochsner Clinical School New OrleansLA 70121USA Bay Area Cosmetic Dermatology San FranciscoCA 94115USA

Aim:Dermal fillers are increasingly popular *** intraarterial injection of fillers,particularly with calcium hydroxylapatite(CaHA),can result in devastating consequences.A systemic review was performed to summarize management strategies to treat CaHA-associated vascular ***:The methodology of this review was derived from The Preferred Reporting Items for Systematic Reviews and meta-analyses(PRISmA).In addition,this paper presents a previously unreported case of a CaHA-associated vascular ***:There were 32 articles describing 42 cases,plus our case included in this *** were 15 cases of vision complications,23 cases of non-vision complications,and 5 experimental *** most common injection sites reported were nasal region for vision complications(45%)and nasolabial folds for non-vision complications(40%).Of the 38 human cases,the most prevalent treatment choice was steroids(24 cases,63%).Complete or near complete improvement was reported in 83%of non-vision complications and 40%of vision *** was no noticeable homogeneity in the management strategies and outcomes of the *** the 5 experimental studies,no clear consensus on treatments was ***:Vascular complications of CaHA are seemingly uncommon,but it is widely suspected that this is due to *** best management is prevention,preparation for a potential complication is equally *** from CaHA literature,hyaluronic acid filler complication protocols,findings of this review,and personal experiences,this report proposes management strategies for CaHA-associated vascular *** hope these strategies provide a much-needed framework for injectors to refer to and utilize as needed.

关键词： Filler-associated intravascular complications filler-associated blindness vascular occlusion management calcium hydroxylapatite Radiesse