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Immune evasion strategies used by Helicobacter pylori

World journal of Gastroenterology 2014年第36期20卷 12753-12766页

作者： taslima t Lina Shatha Alzahrani jazmin Gonzalez Irina v Pinchuk Ellen j Beswick victor E Reyes Department of Microbiology and Immunology University of Texas Medical Branch Galveston TX 77555 United States MS-III School of Medicine University of Texas Medical Branch Galveston TX 77555 United States Department of Internal Medicine University of Texas Medical Branch Galveston TX 77555 United States Departments of Molecular Genetics and Microbiology University of New Mexico Health Sciences Center Albuquerque NM 87131 United States Departments of Pediatrics and Microbiology and Immunology University of Texas Medical Branch Galveston TX 77555 United Statest

Helicobacter pylori(H. pylori) is perhaps the most ubiquitous and successful human pathogen, since it colonizes the stomach of more than half of humankind. Infection with this bacterium is commonly acquired during childhood. Once infected, people carry the bacteria for decades or even for life, if not treated. Persistent infection with this pathogen causes gastritis, peptic ulcer disease and is also strongly associated with the development of gastric cancer. Despite induction of innate and adaptive immune responses in the infected individual, the host is unable to clear the bacteria. One widely accepted hallmark of H. pylori is that it successfully and stealthily evades host defense mechanisms. though the gastric mucosa is well protected against infection, H. pylori is able to reside under the mucus, attach to gastric epithelial cells and cause persistent infection by evading immune responses mediated by host. In this review, we discuss how H. pylori avoids innate and acquired immune response elements, uses gastric epithelial cells as mediators to manipulate host t cell responses and uses virulence factors to avoid adaptive immune responses by t cells to establish a persistent infection. We also discuss in this review how the genetic diversity of this pathogen helps for its survival.

关键词： Helicobacter pylori Immune response Pattern recognition receptors Phagocytes t cells Antigen presenting cells Gastric epithelial cells vacuolating cytotoxin t4SS

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Performance of inclined pillars with a major discontinuity

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International journal of Mining Science and technology 2019年第3期29卷 437-443页

作者： K.v.j.ssu A.j.S.Spearing Western Australia School of Mines Kalgoorlie Curtin University

Discontinuities are an inherent part of the rock mass and majorly affect the stability of the excavation skin and *** dip of the discontinuities and their properties also have a significant effect on the strength of the *** approaches are commonly used to determine the pillar strength but can overestimate the strength and don’t consider the inclination of the pillars and the strength reduction caused by *** modeling is a powerful tool and if calibrated can be used to evaluate the strength of the pillars with discontinuities having a range of *** effect of a discontinuity on inclined pillars was conducted which has been seldom considered in evaluating the pillar ***-dimensional vertical pillars were simulated,and the pillar strength was calibrated to accepted theoretical results and then the discontinuities were introduced in different pillar inclinations with distinct width to height ratios to gain an insight into the effective pillar strength *** upon the results,it was found that the discontinuities have a significant effect with the increase in the inclination of the pillars even at a higher width to height ratios.

关键词： Numerical modelling Pillar Discontinuities Inclination Width to height ratios

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Simplicial Indicator Kriging

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journal of China University of Geosciences 2008年第1期19卷 65-71页

作者： R tolosana-Delgado v Pawlowsky-Glahn j j Egozcue Department of Sedimentology and Environmental Geology Georg-August-Universitt Gttingen D-37077 Gttingen Germany Department of Computer Science and Applied Mathematics University of Girona Girona Spain Department of Applied Mathematics III Universidad Politécnica de Catalunya Barcelona Spain

Indicator kriging （IK） is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. the result is a discrete approximation, and its corresponding estimated probability density function can be viewed as a composition in the simplex. this fact suggested a compositional approach to IK which, by construction, avoids all its standard drawbacks （negative predictions, not-ordered or larger than one）. Here, a simple algorithm to develop the procedure is presented.

关键词： Aitchison geometry compositional data disjunctive kriging log-ratio approach simplex.

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Control of hybrid DC/AC microgrid system employing fuel cell and solar photovoltaic sources using grey wolf optimization

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Clean Energy 2022年第4期6卷 659-670页

作者： Ahmed M.Al-Antaki t.v.Golubchik Mushtaq A.Al-Furaiji H.j.Mohammed Moscow Automobile and Road Construction State technical University(MADI) Leningradsky Ave.64Moscow125319Russian Federation Bauman Moscow State technical University MoscowRussian Federation Faculty of Energy and Ecotechnology ITMO University49 Kronverksky prospectSt.Petersburg197101Russian Federation Department of Mechanical Engineering College of EngineeringUniversity of MisanMisanAl-Amarah62001Iraq Institute of Energy Peter the Great St.Petersburg Polytechnic UniversitySaint Petersburg 195251Russian Federation

the outcome of this study is to improve and enhance the power quality of the hybrid DC/AC microgrid(MG).the photovoltaic(Pv)system and the proton exchange membrane fuel cell(PEMFC)are used as renewable energy sources to deliver the optimum active power to the utility *** MG system based on the Pv system,PEMFC and voltage source inverter is modelled ***,the maximum power point tracking(MPPt)-based grey wolf optimization(GWO)is used to increase the Pv module efficiency and enhance ***,to improve the PEMFC performance,a digital proportional-integral controller is used to control the PEMFC *** proposed inverter is controlled using synchronous reference frame theory,called the direct-quadrature(dq)control ***,the performance of the proposed MG system is tested using MAtLAB®for various weather and loading condi*** the simulation results,the proposed MG system can deliver and absorb an active power based on the Pv and fuel cell *** a result,the hybrid DC/AC MG is enhanced in terms of stabilization of the DC-bus ***,the power quality of the MG is improved using GWO optimization based on ***,good results are achieved using GWO in terms of the total harmonic distortion of the output current of 2.3%and higher efficiency of 98.9%.

关键词： DC/AC inverter optimization

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Biocompatibility of biphasic α,β-tricalcium phosphate ceramics in vitro

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Bioactive Materials 2020年第2期5卷 423-427页

作者： t.v.Safronova I.I.Selezneva S.A.tikhonova A.S.Kiselev G.A.Davydova t.B.Shatalova D.S.Larionov.j.v.Rau Lomonosov Moscow State University Leninskie Gory1Moscow119991Russia Institute of theoretical and Experimental Biophysics Russian Academy of SciencesPushchino142292Moscow RegionRussia Istituto di Struttura Della Materia Consiglio Nazionale Delle Ricerche(ISM-CNR)Via Del Fosso Del Cavaliere 10000133RomeItaly

the biocompatibility of biphasicα,β-tricalcium phosphate ceramics,obtained by annealing a compact preform based onβ-tricalcium phosphate powder,was studied in *** was found that within 10–30 days the adhesion of primary dental pulp stem cells located on the surface of biphasicα,β-tricalcium phosphate ceramics is *** of the cell number on the surface of biphasicα,β-tricalcium phosphate ceramics,most likely,can be associated with both the pH level(acidic)as a result of hydrolysis of the more soluble phase ofα-tricalcium phosphate and with the nature of surface that changes as a result of the formation and growth of hydroxyapatite crystals.

关键词： tricalcium phosphate Ceramics Phase composition Dental pulp stem cells Biocompatibility

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Production and testing of Biogas Using Cow Dung,jatropha and Iron Filins

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journal of Bioresources and Bioproducts 2019年第3期4卷 9-14页

作者： A S ADEKUNLE S E IBItOYE P O OMONIYI L j jILANtIKIRI C v SAM-OBU t YAHAYA Department of Mechanical Engineering University of IlorinIlorinNigeria Department of Biomedical Engineering University of IlorinIlorinNigeria Department of Mechanical Engineering Federal PolytechnicOffaNigeria Department of Material and Metallurgical Engineering University of IlorinIlorinNigeria

Biogas production was investigated in this study as an alternative to wood as fuel using slurries of cow dung(t1),jatropha fruit exocarp(t2),cattle dung and jatropha fruit exocarp(t3)and cow dung,jatropha fruit exocarp with 10 g of iron filings(t4).the 1000 mL of slurry which included 50 mL of inoculum that compensated for the dead or weak micro-organism was made for each *** the end of five weeks,the volume of biogas collected from the samples t1,t2,t3,and t4 when added up,gave 77,154,145 and 586 mL,*** sample mixture of cow dung,jatropha fruit exocarp,and iron filings(t4),gave the highest yield of biogas production with an average weekly production of 59 mL/kg for four weeks and on the fifth week about six times emission of biogas was *** production rate of the biogas was rapid after the gestation period and the t4 emerged as the most substantial emission of all the samples producing 350 mL/kg on the fifth week.

关键词： anaerobic digestion bacteria biodegradable biogas

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A primitive mantle source for the Neoarchean mafic rocks from the tanzania Craton

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Geoscience Frontiers 2016年第6期7卷 911-926页

作者： Y.A.Cook I.v.Sanislav.j.Hammerli t.G.Blenkinsop P.H.G.M.Dirks Economic Geology Research Centre(EGRU)and Department of Earth and Oceans James Cook UniversityTownsville4011OLDAustralia School of Earth&Ocean Sciences Cardiff UniversityCardiff CF10 3ATUnited Kingdom

Mafic rocks comprising tholeiitic pillow basalt, dolerite and minor gabbro form the basal stratigraphic unit in the ca. 2.8 to 2.6 Ga Geita Greenstone Belt situated in the NW tanzania Craton. they outcrop mainly along the southern margin of the belt, and are at least 50 million years older than the supracrustal assemblages against which they have been juxtaposed. Geochemical analyses indicate that parts of the assemblage approach high Mg-tholeiite （more than 8 wt.% MgO）. this suite of samples has a restricted compositional range suggesting derivation from a chemically homogenous reservoir. trace element modeling suggests that the mafic rocks were derived by partial melting within the spinel peridotite field from a source rock with a primitive mantle composition. that is, trace elements maintain primitive mantle ratios （Zr/Hf = 32-35, ti/Zr - 107-147）, producing flat REE and HFSE profles [（La/Yb）pm = 0.9 -1.3], with abundances of 3-10 times primitive mantle and with minor negative anomalies of Nb [（Nb/ La）pm - 0.6-0.8] and th [（th/La）pm = 0.6-0.9]. Initial isotope compositions （εNd） range from 1.6 to 2.9 at 2.8 Ga and plot below the depleted mantle line suggesting derivation from a more enriched source compared to present day MORB mantle. the trace element composition and Nd isotopic ratios are similar to the mafic rocks outcropping -50 km south. the mafic rocks outcropping in the Geita area were erupted through oceanic crust over a short time period, between -2830 and-2820 Ma; are compositionally homogenous, contain little to no associated terrigenous sediments, and their trace element composition and short emplacement time resemble oceanic plateau basalts. they have been interpreted to be derived from a plume head with a primitive mantle composition.

关键词： Mafic rocks Archean tanzania Craton Primitive mantle MORB Oceanic plateau

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由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bulletin 2024年第4期69卷 449-457页

作者： LHAASO Collaboration Zhen Cao Chuandong Gao Cong Li Ruo-Yu Liu Ruizhi Yang 不详 Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China tIANFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and technology of China Hefei 230026China

We report the detection of aγ-ray bubble spanning at least 100deg2 in ultra-high energy(UHE)up to a few Pev in the direction of the star-forming region Cygnus X,implying the presence super Pevatron(s)accelerating protons to at least 10 Pev.A log-parabola form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10 tev)is found fitting the gamma-ray energy spectrum of the bubble *** sources,“hot spots”correlated with very massive molecular clouds,and a quasi-spherical amorphousγ-ray emitter with a sharp central brightening are observed in the *** the core of~0.5°,spatially associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as well as previously reported multi-tev sources,an enhanced concentration of UHEγ-rays is observed with 2 photons at energies above 1 *** general feature of the bubble,the morphology,and the energy spectrum,are reasonably reproduced by the assumption of a particle accelerator in the core,continuously injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstellar medium Star cluster

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Effects of grain size and Al addition on the activation volume and strain-rate sensitivity of CoCrFeMnNi high-entropy alloy

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journal of Materials Science & technology 2023年第12期143卷 242-252页

作者： H.t.jeong W.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul121-791Republic of Korea

the activation volume(v∗)and strain-rate sensitivity exponent(m)of CoCrFeMnNi and Al_(0.5)CoCrFeMnNi high entropy alloys(HEAs)with various grain sizes(ranging between 2.4 and 356μm)were measured at different strain rates and strain levels at room *** the strain rate decreased,the plastic strain decreased,and the grain size increased,v∗*** enhanced solid-solution strengthening by addition of aluminum decreased v∗.the Hassen plot was modified to capture the grain-size depen-dence of v∗by considering the grain-size dependence of the dislocation *** the plastic strain increased,the strain rate decreased,and the grain size decreased,m *** behavior of m could be quantitatively predicted by using equations derived for the grain-size-dependent v∗and flow *** difference in the grain-size dependence of m between conventional face centered cubic(FCC)metals and FCC HEAs over the nanograin size range could not be explained in terms of a relatively large Hall-Petch slope of the FCC HEAs compared with that of the FCC conventional metals,but was explainable in terms of a substantially higher probability of activation of grain-boundary diffusion-controlled grain-boundary-sliding mechanism at nanograin sizes in the FCC conventional metals than in the FCC HEAs.

关键词： Grain size High entropy alloys Activation volume Strain-rate sensitivity Solid solution

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Improved Secure Identification-Based Multilevel Structure of Data Sharing in Cloud Environments

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Computer Systems Science & Engineering 2022年第11期43卷 785-801页

作者： Saraswathi Shunmuganathan Sridharan Kannan t.v.Madhusudhana Rao K.Ambika t.jayasankar Department of Computer Science and Engineering SSN College of EngineeringChennaiTamil Nadu603110India Department of Computer Science and Engineering J.K.K.Munirajah College of TechnologyErodeTamil Nadu638506India Department of Computer Science and Engineering Vignan’s Institute of Information TechnologyVisakhapatnam530049India Department of Computer Science and Engineering University College of EngineeringBIT CampusAnna UniversityTiruchirappalliTamil Nadu620024India Department of Electronics and Communication Engineering University College of EngineeringBIT CampusAnna UniversityTiruchirappalli620024India

the Cloud Computing Environment(CCE)developed for using the dynamic cloud is the ability of software and services likely to grow with any *** has transformed the methodology for storing the enterprise data,accessing the data,and Data Sharing(DS).Big data frame a constant way of uploading and sharing the cloud data in a hierarchical architecture with different kinds of separate privileges to access the *** the requirement of vast volumes of storage area in the CCEs,capturing a secured data access framework is an important *** paper proposes an Improved Secure Identification-based Multilevel Structure of Data Sharing(ISIMSDS)to hold the DS of big data in *** complex file partitioning technique is proposed to verify the access privilege context for sharing data in complex *** access control Encryption Method(EM)is used to improve the *** Complexity is measured to increase the authentication *** active attack is protected using this ISIMSDS *** proposed ISIMSDS method assists in diminishing the Complexity whenever the user’s population is increasing *** security analysis proves that the proposed ISIMSDS methodology is more secure against the chosen-Plaintext(Pt)attack and provides more efficient computation and storage space than the related *** performance of the proposed ISIMSDS methodology provides more efficiency in communication costs such as encryption,decryption,and retrieval of the data.

关键词： Data sharing cloud environments big data chosen-plaintext attack security

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