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Microbiota modification by probiotic supplementation reduces colitis associated colon cancer in mice

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World Journal of Gastroenterology 2018年第18期24卷 1995-2008页

作者： Maria carolina S Mendes Daiane SM Paulino Sandra R Brambilla juliana A camargo Gabriela F Persinoti José Barreto c carvalheira Department of Internal Medicine Faculty of Medical Sciences State University of Campinas (UNICAMP) Brazilian Bioethanol Science and Technology Laboratory (cTBE) Brazilian Center for Research in Energy and Materials (CNPEM)

AIM To investigate the effect of probiotic supplementation during the development of an experimental model of colitis associated colon cancer(cAc). METHODS c57 BL/6 mice received an intraperitoneal injection of azoxymethane(10 mg/kg), followed by three cycles of sodium dextran sulphate diluted in water(5% w/v). Probiotic group received daily a mixture of Lactobacillus acidophilus, Lactobacil us rhamnosus and Bifidobacterium bifidum. Microbiota composition was assessed by 16 Sr RNA Illumina Hi Seq sequencing. colon samples were collected for histological analysis. Tumor cytokines was assessed by Real Time-PcR(Polymerase chain Reaction); and serum cytokines by Multiplex assay. All tests were two-sided. The level of significance was set at P cal analysis performed using the software Graph Pad Prism 5.0. The project was approved by the institutional review board committee. RESULTS At day 60 after azoxymethane injection, the mean number of tumours in the probiotic group was 40% lower than that in the control group, and the probiotic group exhibited tumours of smaller size(ce in richness and diversity between groups. However, there was a significant difference in beta diversity in the multidimensional scaling analysis. The abundance of the genera Lactobacillus, Bifidobacterium, Allobaculum, clostridium XI and clostridium XvⅢ increased in the probiotic group(P crobial change was accompanied by reduced colitis, demonstrated by a 46% reduction in the colon inflammatory index; reduced expression of the serum chemokines RANTES and Eotaxin; decreased p-IKK and TNF-α and increased IL-10 expression in the colon. cONcLUSION Our results suggest a potential chemopreventive effect of probiotic on cAc. Probiotic supplementation changes microbiota structure and regulates the inflammatory response, reducing colitis and preventing cAc.

关键词： Intestinal microbiota chemoprevention Lactobacillus acidophilus Lactobacillus rhamnosus Bifidobacterium bifidum

Analytical modeling of effect of interlayer on effective moduli of layered graphene-polymer nanocomposites

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Journal of Materials Science & Technology 2017年第8期33卷 827-833页

作者： c.c.Roach Y.c.Lu Department of Mechanical Engineering University of KentuckyLexingtonKY 40506-0503USA

Nanocomposites enhanced with two-dimensional, layered graphene fillers are a new class of engineering materials that exhibit superior properties and characteristics to composites with conventional ***, the roles of ＂interlayers＂ in layered graphene fillers have yet to be fully explored. This paper examines the effect of interlayers on mechanical properties of layered graphene polymer *** an effective filler, the fundamental properties（in-plane Young＇s modulus E（L1）, out-of-plane Young＇s modulus E（L2）; shear modulus G（L12）, major Poisson＇s ratio v（L12）） of the layered graphene were computed by using the Arridge＇s lamellar model. The effects of interlayers on effective moduli of layered graphene epoxy composites were examined through the Tandon-Weng model. The properties of the interlayer show noticeable impact on elastic properties of the composites, particular the out-of-plane properties（Young＇s modulus E2 and shear modulus G（12））. The interlayer spacing is seen to have much great influence on properties of the composites. As the interlayer spacing increases from 0.34 nm to 2 nm, all elastic properties of the composites have been greatly decreased.

关键词： Interlayer Layered graphene Nanocomposite Effective moduli

Numerical Methods for Solving the Hartree-Fock Equations of Diatomic Molecules I

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communications in computational Physics 2009年第5期5卷 959-985页

作者： John c.Morrison Scott Boyd Luis Marsano Bernard Bialecki Thomas Ericsson Jose Paulo santos Department of Physics University of LouisvilleLouisvilleKY40292USA Department of Mathematical and computer Sciences Colorado School of MinesGoldenCO 80401-1887USA Department of Mathematical Sciences Chalmers University of Technology and the University of GothenburgSE-41296 GothenburgSweden Department of Physics New University of LisbonLisbonPortugal

The theory of domain decomposition is described and used to divide the variable domain of a diatomic molecule into separate regions which are solved *** approach makes it possible to use fast Krylov methods in the broad interior of the region while using explicit methods such as Gaussian elimination on the *** is demonstrated by solving a number of model problems,these methods enable one to obtain solutions of the relevant partial differential equations and eigenvalue equations accurate to six significant figures with a small amount of computational *** the numerical approach described in this article decomposes the variable space into separate regions where the equations are solved independently,our approach is very well-suited to parallel computing and offers the long term possibility of studying complex molecules by dividing them into smaller fragments that are calculated separately.

关键词： Fast Krylov methods splines Hartree-Fock equations diatomic molecules eigenvalue problem

Unravelling the competitive effect of microstructural features on the fracture toughness and tensile properties of near beta titanium alloys

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Journal of Materials Science & Technology 2022年第2期97卷 101-112页

作者： Yang Liu Samuel c.v.Lim chen Ding Aijun Huang Matthew Weyland Department of Materials Science and Engineering Monash UniversityClaytonVIC3800Australia Monash centre for Additive Manufacturing Monash UniversityNotting HillVIC3168Australia BAOWU Special Metallurgy co.Ltd. Shanghai200940China Monash centre for Electron Microscopy Monash UniversityClaytonVIC3800Australia

The competitive effect of microstructural features including primaryα(α_(p)),secondaryα(α_(s)),grain boundaryα(α_(GB)) and β grain size on mechanical properties of a near β Ti alloy were studied with two heat treatment *** relative effect of β grain size and STA(solution treatment and ageing)processing parameters on mechanical properties were quantitatively explored by the application of Taguchi *** results were further explained via correlating microstructure with the fracture toughness and tensile *** was found that large numbers of fine as precipitates and continuous α_(s) played greater roles than other features,resulting in a high strength and very low ductility(cess *** β grain size had a negative correlation with fracture *** the samples prepared by BAScA( β anneal slow cooling and ageing)process,improved ductility and fracture toughness were obtained due to a lower density ofα;precipitates,a basket-weave structure and zigzag morphology of α_(GB).For this heat treatment,an increase in prior β grain size had an observable positive effect on fracture *** contradictory effect of β grain size on fracture toughness found in literature was for the first time *** was shown that the microstructure obtained from different processes after β solution has complex effect on mechanical *** complexity derived from the competition between microstructure features and the overall sum of their effect on fracture toughness and tensile properties.A novel table was proposed to quasi-quantitatively unravel these competitive effects.

关键词： Nearβtitanium alloys Microstructural features competitive effect Fracture toughness βgrain size effect

Prevalence and factors associated with stages of behavior change for physical activity in adolescents:a systematic review

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World Journal of Pediatrics 2017年第3期13卷 202-209页

作者： Heloyse Elaine Gimenes Nunes Diego Augusto santos Silva Eliane cristina de Andrade Gon(c)alves Federal University of Santa catarina Post-Graduate Program in Physical EducationFlorianópolisSanta CatarinaBrazil

Background:To analyze prevalence and factors associated with stages of behavior change for physical activity in *** sources:A search was performed in SciELO,PubMed,PsycINFO,SPORTDiscus and *** search terms were 'behavior change' OR 'stages of change' OR 'stages of readiness' OR 'readiness to change' OR 'transtheoretical model' OR 'process to change' OR 'decisional balance',and 'motor activity' OR 'physical activity' OR 'physical exercise' and 'adolescent' OR 'students'.After the eligibility criteria,18 articles were ***:The highest prevalence of adolescents in the precontemplation,contemplation,and preparation stages was found in the Germany,South Korea,and Iran while there were more adolescents in the action and maintenance in South Korea and *** evidence of association indicated that females are more likely to be in precontemplation,contemplation and *** evidence was inconclusive for age (in relation to the precontemplation,contemplation,action and maintenance stages),economic status (all stages),shift of study (when stratified by gender) and body composition (all stages).No association was found with parental level of ***:The findings can help to guide interventions and further research on the topic of behavior changes for physical activity in adolescents.

关键词： adolescent behavior motor activity students transtheoretical model

crustal reworking and orogenic styles inferred from zircon Hf isotopes:Proterozoic examples from the North Atlantic region

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Geoscience Frontiers 2019年第2期10卷 417-424页

作者： c.J.Spencer c.L.Kirkland A.R.Prave R.A.Strachan v.Pease Earth Dynamics Research Group The Institute of Geoscience Research (TIGeR)Department of Applied GeologyCurtin University centre for Exploration Targeting d curtin Node Department of Applied GeologyCurtin University Department of Earth and Environmental Sciences University of St Andrews School of Earth and Environmental Sciences University of Portsmouth Department of Geological Sciences Stockholm University

Zircon Hf evolutionary patterns are powerful tools to investiage magma petrogenesis and crustal evolution. The ^(176)Hf/^(177)Hf isotopic signature of a rock is particularly informative and can be used to derive an estimation of the time when mantle extraction and diagnose closed system reworking where successive samples through time define an Hf evolution array dependant on the source Lu/Hf ratio. However, many magmatic events require new mantle addition as the thermal impetus for melting pre-existing crust. In this situation, rather than simply reflecting reworking, the isotopic signature indicates mixing with contributions from both reworked crust and new radiogenic input. Different geodynamic settings have different propensities for either reworking or addition of new mantle-derived magma. Hence, Hf-time trends carry within them a record, albeit cryptic, of the evolving geodynamic environment as different tectonic configurations recycle and add new crust at different rates, magnitudes, and from different sources. As an example of the difference in apparent Hf evolution slopes, we present Hf-time compilations from three geographically distinct Meso-to Neoproterozoic orogenic belts in the North Atlantic Region whose geodynamic configurations remain a subject of debate. We use the εHf/Ma trajectory to assist in understanding their evolution. The εHf/Ma trajectory of the Sveconorwegian Orogen corresponds to a ^(176)Lu/^(177) Hf ratio of 0.012, which implies a process driven primarily by reworking of preexisting crust that is balanced with input from the depleted mantle resulting in a relatively shallowεHf/Ma slope. The valhalla Orogen reveals a similar comparatively shallow εHf/Ma path. In stark contrast to these patterns is the steep εHf/Ma trajectory of the Grenville Orogen that requires a mixing process involving a greater contribution of old crust of at least ～ 1.8 Ga age. The degree of reworking required to produce the εHf/Ma trend of the Grenville Orogen is co

关键词： Zircon Hf crustal evolution Grenville Sveconorwegian valhalla

Growth mechanism of octahedron-like BaMoO_4 microcrystals processed in microwave-hydrothermal:Experimental observations and computational modeling

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Particuology 2009年第5期7卷 353-362页

作者： Laécio santos cavalcante Júlio césar Sczancoski Rircado Luis Tranquilin José Arana varela Elson Longo Marcelo Ornaghi Orlandi Departamento de Química UFSCarP.O. Box 67613565-905So CarlosSPBrazil Instituto de Química-UNESP P.O. Box 35514801-907AraraquaraSPBrazil

Octahedron-like BaMoO4 microcrystals were synthesized by the co-precipitation method at room temperature and processed in microwave-hydrothermal at 413 K for different times （from 30 min to 5 h）. These microcrystals were analyzed by X-ray diffraction （XRD）, field-emission gun scanning electron microscopy （FEG-SEM） and transmission electron microscopy （TEM）. XRD patterns showed that this material presents a tetragonal structure without the presence of deleterious phases. FEG-SEM and TEM micrographs revealed that the BaMoO4 microcrystals present an octahedron-like morphology with agglomerate nature and polydisperse particle size distribution. These micrographs also indicated that the microcrystals grow along the [0 01 ] direction. The observed crystallographic planes in these structures were modeled computationally and a crystal growth model was proposed in order to explain the morphological changes as a function of processing time.

关键词： BaMoO4 Growth process Microwave-hydrotherma Supersaturated solution

Development of Junction Elements from Study of the Bionics

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Journal of Bionic Engineering 2007年第1期4卷 41-46页

作者： Wilson Kindlein Junior Luis Henrique Alves cndido André canal Marques Sandra Souza dos santos Maurício da Silva viegas Laboratory of Design and Material Selection-LdSM-Materials Department (DEMAT) School of Engineering–EE Federal University of Rio Grande do Sul-Brazil-UFRGS Brazil

The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in reference to the effectiveness of product dismount aiming the reduction of ambient impact in all its phases of use. The creation, the development and the confection of new junction elements were described, and case studies of new products developed specifically with this purpose were presented.

关键词： bionics Ecodesign junction elements

Positional goods and the challenge of chinese regional inequality

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Economic and Political Studies 2018年第1期6卷 4-10页

作者： John v.c.Nye Department of Economics George Mason UniversityFairfaxVAUSA NRU-Higher Schoolof Economics MoscowRussia

Scholars have focussed on income inequality as a major source of social *** the focus on crude income inequality has masked the deeper developmental problem facing many fast-growing *** is an extreme case of this issue inasmuch as its coastal regions can be viewed as comparable to middle income states,while the greater part of its rural and west-erm areas would be comparable to the poorer nations of the *** means that the new middle class pays attention to issues such as pollution and status or positional goods than simple material *** costs of houses are in particular less than *** status goods are similar because they are not amenable to simple productivity *** will make policies more difficult as conflict increases between those areas who are still eager for basic economic development and those richer areas whose wants and needs start to more closely resemble the preferences of richer developed countries.

关键词： Positional goods regional inequality statusgoods