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Prevalence of vacA, cagA and babA2 genes in Cuban Helicobacter pylori isolates

World Journal of Gastroenterology 2009年第2期15卷 204-210页

作者： Lino E Torres Karelia Melián Arlenis Moreno Jordis Alonso Carlos A sabatier Mayrín Hernández Ludisleydis Bermúdez Boris L Rodríguez Department of Microbiology and Immunology Biotechnology Division National Centre for Scientif ic Research Ciudad de La Habana Cuba Department of Gastroenterology Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba Anatomopathology Department Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba

AIM： To investigate the prevalence of vacuolating cytotoxin （vacA）, cytotoxin associated gene A （cagA） and blood adhesion binding antigen （babA2） genotypes of Helicobacter pylori （H pylori） isolates from Cuban dyspeptic patients. METHODs： DnA was extracted from Hpylori-positive cultures taken from 130 dyspeptic patients. Genotyping was performed by PCR, using specific primers for vacA （s1, s2, m1, m2）, cagA and babA2 genes. Endoscopic observations and histological examinations were used to determine patient pathologies. REsULTs： vacA alleles s1, s2, m1 and m2 were detected in 96 （73.8%）, 34 （26.2%）, 75 （57.7%） and 52 isolates （40%）, respectively, while the cagA gene was detected in 95 isolates （73.2%）. One hundred and seven isolates （82.3%） were babA2-positive. A significant correlation was observed between vacAs1m1 and cagA and between vacAs1ml and babA2 genotypes （P 〈 0.001 and P 〈 0.05, respectively） and between babA2 genotype and cagA status （P 〈 0.05）; but, no correlation was observed between vacAsl and babA2 genotypes. Eighty five （65.4%） and 73 （56.2%） strains were type 1 （vacAsl-cagA-positive） and ＂triplepositive＂（vacAs1-cagA-babA2-positive）, respectively, and their presence was significantly associated with duodenal ulcer （P 〈 0.01 and P 〈 0.001, respectively）. COnCLUsIOn： The distribution of the main virulence factors in the Cuban strains in this study resembled that of the Western-type strains, and the more virulent H pylori isolates were significantly associated with duodenal ulcer, ulcer disease being the worst pathology observed in the group studied.

关键词： Cuban dyspeptic patients He/icobacterpylori vacA, cagA and babA

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Factors determining the occupancy of nest-boxes by Great Tits(Parus major)in eucalypt plantations

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Avian Research 2023年第2期14卷 200-205页

作者： Ricardo s.Ceia Pedro B.Lopes Luís Pda silva Centre for Functional Ecology–science for People&the Planet Department of Life SciencesUniversity of Coimbra3000-456CoimbraPortugal CIBIO Centro de Investigaçao em Biodiversidade e Recursos GeneticosInBIO Laboratorio AssociadoCampus de Vair aoUniversidade do Porto4485-661VairaoPortugal BIOPOLIs Program in Genomics Biodiversity and Land PlanningCIBIOCampus de Vai~ao4485-661VairaoPortugal

Providing nest-boxes as surrogate tree cavities can be of great importance to increase the breeding populations of cavity-nesting birds in managed ***,the exact placement of nest-boxes should be taken into consideration to enhance their occupancy according to species-specific *** this study,we investigated which factors can better predict nest-box occupancy by the Great Tit(Parus major)in eucalypt *** used generalised linear mixed-effects models to analyse the influence of topography,nest-box positioning,vegetation cover and landscape variables on three-year occupancy records from 80 newly provided ***-random patterns of nest-box occupancy were found with respect to all categories except *** suggest that Great Tits prefer to occupy high-placed nest-boxes,close to areas that can provide them with supplementary resources either within or in the vicinity of the stand(i.e.,trees other than eucalypts,riparian vegetation,and large patches of adjacent habitats).Overall,this study provides important recommendations for nest-box placement and spatial distribution in managed forests and enhances the potential of nest-box interventions as a biodiversity offset and management tool.

关键词： Eucalyptus globulus Managed forest nest-site attributes secondary cavity-nester species-specific preferences Tit

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Linear and nonlinear optical analysis on semiorganic-proline cadmium chloride single crystal

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Chinese Physics B 2018年第4期27卷 476-482页

作者： Mohd Anis M I Baig s s Hussaini M D shirsat Mohd shkir H A Ghramh Department of Physics Sant Gadge Baba Amravati University Amravati-444602 Maharashtra India Ram Meghe College of Engineering and Management Amravati-444701 Maharashtra India Crystal Growth Laboratory Department of Physics Milliya Arts Science and Management Science College Beed431122 Maharashtra India RUsA Center for Advanced sensor Technology Department of Physics Dr. Babasaheb-Ambedkar-Marathwada University A urangabad-431005 Maharashtra India Research Center for Advanced Materials science (RCAMs) King Khalid University P. O. Box 9004 Abha-61413 Saudi Arabia Advanced Functional Materials & Optoelectronic Laboratory (AFMOL) Department of Physics College of Science King Khalid University P. O. Box 9004 Ahha-61413 Saudi Arabia

In the current investigation,L-proline cadmium chloride monohydrate（LPCC） single crystal is grown by a slow solvent evaporation technique to identify its credibility for nonlinear optical device *** constituent elements of LPCC crystal are determined by the energy dispersive spectroscopic（EDs） *** single crystal x-ray diffraction technique is used to determine the structural dimensions of LPCC *** UV-visible studies are carried out within a wavelength range of 200 nm–1100 nm to determine the optical transmittance of LPCC *** linear optical parameters of LPCC crystal are evaluated using the transmittance data to discuss its importance for distinct optical *** nd：YAG laser assisted Kurtz–Perry test is carried out to determine the enhancement in second harmonic generation efficiency of LPCC crystal with reference to KDP *** Z-scan technique is employed to assess the third order nonlinear optical（TOnLO） properties of LPCC crystal at 632.8 *** Z-scan data are utilized to evaluate the TOnLO refraction,absorption and susceptibility of LPCC *** color oriented luminescence behavior of LPCC crystal is investigated within a spectral range of 350 nm–700 *** dependence of dielectric constant and dielectric loss on temperature and frequency is evaluated through the dielectric measurement studies.

关键词： crystal growth dielectric studies nonlinear optical materials optical studies

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Radiation-induced sarcomas of the head and neck

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World Journal of Clinical Oncology 2014年第5期5卷 973-981页

作者： Anuradha Thiagarajan n Gopalakrishna Iyer Department of Radiation Oncology National Cancer Centre Singapore Department of surgical Oncology National Cancer Centre Singapore

With improved outcomes associated with radiotherapy, radiation-induced sarcomas(RIs) are increasingly seen in long-term survivors of head and neck cancers, with an estimated risk of up to 0.3%. They exhibit no subsite predilection within the head and neck and can arise in any irradiated tissue of mesenchymal origin. Common histologic subtypes of RIs parallel their de novo counterparts and include osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma/sarcoma nitricoxide synthase, and fibrosarcoma. While imaging features of RIs are not pathognomonic, large size, extensive local invasion with bony destruction, marked enhancement within a prior radiotherapy field, and an appropriate latency period are suggestive of a diagnosis of RIs. RIs development may be influenced by factors such as radiation dose, age at initial exposure, exposure to chemotherapeutic agents and genetic tendency. Precise pathogenetic mechanisms of RIs are poorly understood and both directly mutagenizing effects of radiotherapy as well as changes in microenvironments are thought to play a role. Management of RIs is challenging, entailing surgery in irradiated tissue and a limited scope for further radiotherapy and chemotherapy. RIs is associated with significantly poorer outcomes than stagematched sarcomas that arise independent of irradiationand surgical resection with clear margins seems to offer the best chance for cure.

关键词： Post-irradiation nasopharyngeal carcinoma In-field Radiotherapy Head and neck cancer

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Phase Formation and Magnetic Properties of nanocomposite nd-Fe-B Adjusted by small Amount of Dy and Co

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Journal of Rare Earths 2004年第Z2期22卷 89-94页

作者： T s Jang T W Lim H s Aum D H Lee M B Kim Division of Materials and Chemical Engineering Sun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Mechanical EngineeringSun Moon University 100 Kalsan LiTangjung MyonAsan CityChoongnam 336-708Korea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea

In order to improve and stabilize the magnetic properties of nanocomposite nd2Fe14B/α-Fe magnetic alloys by a compositional adjustment, small amount of Dy and/or Co was added to nd9Fe84B7 alloys. DTA analysis on the amorphous of the alloys took place as the soft magnetic phases were crystallized, and then the hard magnetic nd2Fe14B was precipitated from them. While α-Fe and a metastable 1:7 (TbCu7-type) phase were formed simultaneously in Dy and Co-free alloys, they were crystallized separately at different temperatures after Dy or Co was added. This phase separation occurred more clearly in the Dy-treated alloys and the other soft magnetic phase Fe3B was also stabilized by Dy and/or Co. The 1: 7 phase that was stabilized by Dy and/or Co was not eliminated at 700 ℃, decreasing magnetic properties of the alloys. It was eventually disappeared above 725 ℃, but Fe3B was not eliminated even at 750 ℃ when Dy was added more than 0.5 at% or Co was added more than 2.0 at%. Amount of nd2Fe14B in the alloys tended to increase as Dy addition increased,whereas Co addition did not lead to any appreciable change in the ratio of α-Fe and nd2Fe14B. Moreover, Dy addition apparently increased coercivity of an alloy while Co addition had a beneficial effect on remanence. The grains in the Dytreated alloys were usually finer than those in the Co-treated alloys. The grain size of both α-Fe and nd2Fe14B in the alloys exhibiting mr ≥ 0.72 was in the range of 20 ～ 40 nm or even larger 50 nm, which is larger than the theoretical optimum size ( ～ 10 nm). Typical magnetic properties obtained from a nd7.5Dy1.5Fe82.5Co1.5B7 alloy annealed for 12 min at 725 ℃were iHc=4.85 kOe, Br= 11.32 kG, (BH)max = 15.73 MGOe, and mr=0.73.

关键词： nanocomposite nd-Fe-B magnetic properties remanence coercivity

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synthesis and spectral characterization of lanthanide complexes with 1,2-diphenyl-4-butyl-3,5-pyrazolidinedione: Luminescent property of Tb(Ⅲ) complex

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Journal of Rare Earths 2012年第7期30卷 709-715页

作者： M.R.Anoop P.s.Binil s.suma M.R.sudarsanakumar Department of Chemistry S.N. College Department of Chemistry S.N .College Depart-ment of Chemistry M.G. College

The complexes of rare earth elements with 1,2-diphenyl-4-butyl-3,5-Pyrazolidinedione （PBH, phenylbutazone） were synthesized and characterized by elemental analysis, molar conductance, IR, UV-Vis, EPR and magnetic moment measurements. Based on these studies the complexes were formulated as [Ln（PB）3（H2O）2].nH2O, where Ln=Eu（III）, Gd（III）, Tb（III）, Dy（III） and Er（III）. From IR spectra, it was found that PBH acted as a bidentate mono-ionic ligand coordinating through two carbonyl oxygen of the pyrazolidinedione ring. The thermal analysis of all the complexes was carried out at a heating rate of 10 oC/min. The kinetic aspects of the complexes were evaluated. The nega-tive entropy value of the complexes indicated a more ordered state for the activated complexes. The photoluminescence property of Tb（III） complex was investigated. It showed all the characteristic emission peaks of Tb^3＋ with a life time of 0.98914 ms.

关键词： lanthanide complexes IR thermal analysis luminescent properties rare earths

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Apatite Loss in Pothwar Loess Plain(Pakistan) Fits a simple Linear Reservoir Model

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Pedosphere 2014年第6期24卷 763-775页

作者： M.s.AKHTAR M.IMRAn A.MEHMOOD M.MEMOn s.RUKH G.s.KIAnI Department of soil science and soil water Conservation PMAS-Arid Agriculture University Rawalpindi Department of soil science Sindh Agriculture University

Apatite is the dominant phosphorus(P) mineral in early stages of soil development, and its redistribution as labile forms under pedogenesis controls terrestrial bioavailability. Quantitative distribution of labile forms of P and apatite-P was examined in Pothwar Loess Plain, Pakistan where the degree of pedogenesis varied with relief. Four soil types, Typic Ustorthents(Rajar), Typic Calciustepts(Missa), Udic Calciustepts(Basal), and Udic Haplustalfs(Guliana), were sampled from three replicated locations at genetic horizon level. With the exception of total P value at surface, the mean total and apatite-P decreased towards the surface in Udic Haplustalfs and Udic Calciustepts where dicalcium and octacalcium phosphate increased toward surface. Iron(oxides and oxyhydroxides) adsorbed and occluded P forms were also in greater quantities in Udic Haplustalfs and increased toward the surface, whereas they were lowest and uniform in the Typic Ustorthents. Aluminum- and organic P correlated with soil organic matter. Apatite-P decreased exponentially with an increase in the sum of iron adsorbed and occluded P fractions, and fitted the equation M(x)= M0 [1- exp(-wx)] with r2= 0.996, where M(x)is the mean apatite-P concentration in solum, M0 is the apatite-P content in the loess sediments, x is the cumulative iron adsorbed and occluded P, and w is an empirical factor indicating the change rate of apatite-P in the loess. From the calculated apatite-P of 740 mg kg-1at the time of deposition, mean apatite-P loss was 60% in Udic Haplustalfs, 33% in Udic Calciustepts, 23% in Typic Calciustepts, and 8% in Typic Ustorthents. The transformation of soil P to labile forms was faster and deeper in level or slight depressions followed by gently sloping areas in wide plains, and was the least in the gullied land.

关键词： labile forms pedogenic iron oxides phosphorus distribution phosphorus fractions toposequence

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MECHAnICAL PROPERTIEs OF HYBRID GLAss/sUGAR PALM FIBRE REInFORCED UnsATURATED POLYEsTER COMPOsITEs

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Chinese Journal of Polymer science 2013年第10期31卷 1394-1403页

作者： s.M.sapuan H.Y.Lok M.R.Ishak s.Misri Department of Mechanical and Manufacturing Engineering Universiti Putra Malaysia43400 UPM Serdang Selangor Malaysia Institute of Advanced Technology (ITMA) Universiti Putra Malaysia43400 UPM Serdang Selangor Malaysia Institute of Tropical Forestry and Forest Products (InTROP) Universiti Putra Malaysia43400 UPM SerdangSelangor Malaysia Faculty of Engineering and Technology Multimedia UniversityJalan Ayer Keroh Lama75450 Bukit Beruang Melaka Malaysia Department of Aerospace Engineering Universiti Putra Malaysia43400 UPM Serdang Selangor Malaysia

A research has been carried out to investigate the mechanical properties of composites made by hybridizing sugar palm fibre （Arenga pinnata） with glass fibre into an unsaturated polyester matrix. Hybrid composites of glass/sugar palm fibre were fabricated in different weight ratios of strand mat glass fibres ： sugar palm fibres 4：0, 4：1, 4：2, 4：3, 4：4, and 0：4. The hybrid effects of glass and sugar palm fibre on tensile, flexural and impact properties of the composites were evaluated according to AsTM D5083, AsTM D790 and AsTM D256 respectively. Results have been established that properties of hybrid glass/sugar palm composites such as tensile strength, tensile modulus, elongation at break, toughness, flexural strength, flexural modulus and impact strength are a function of fibre content. The failure mechanism and the adhesion between fibres/matrix were studied by observing the scanning electron micrographs of impact fracture samples. In general, the incorporation of both fibres into unsaturated polyester matrix shows a regular trend of increase in the mechanical properties.

关键词： Tensile test Flexural test Impact test Hybrid composite sugar palm fibre.

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Exact solutions in generalized Oldroyd-B fluid

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 411-426页

作者： T. HAYAT s. ZAIB s. AsGHAR A. A. HEnDI Department of Mathematics Quaid-i-Azam University Department of Mathematics Comsats Institute of Information Technology Department of Physics Faculty of Science King Saud University

This investigation deals with the influence of slip condition on the magne- tohydrodynamic （MHD） and rotating flow of a generalized Oldroyd-B （G. Oldroyd-B） fluid occupying a porous space. FractionM calculus approach is used in the mathematical modeling. Three illustrative examples induced by plate oscillations and periodic pressure gradient are considered, and the exact solutions in each case are derived. Comparison is provided between the results of slip and no-slip conditions. The influence of slip is highlighted on the velocity profile by displaying graphs.

关键词： slip condition exact solution fractional calculus

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研究生招生考试报考中的“偏好误识”分析——基于公共部门理论的视角

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中国地质大学学报（社会科学版） 2009年第4期9卷 113-117页

作者：米红李小娃厦门大学高等教育研究中心福建厦门361005 浙江大学公共管理学院浙江杭州310058

随着我国研究生教育规模的扩大,研究生招生的报考过程中出现区域集中、专业集中、学校集中、招生单位宣传加剧等现象。这些现象的出现不仅在于扩招的大背景,还在于研究生教育的公共物品的本质属性,以及研究生招生考试管理中的偏好误识... 详细信息

随着我国研究生教育规模的扩大,研究生招生的报考过程中出现区域集中、专业集中、学校集中、招生单位宣传加剧等现象。这些现象的出现不仅在于扩招的大背景,还在于研究生教育的公共物品的本质属性,以及研究生招生考试管理中的偏好误识和考生"经济人"角色的偏好选择。因此,从公共部门理论的视角分析并解决上述问题成为解决报考中不合理现象的一条重要途径。

关键词：研究生教育报考偏好误识公共部门

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