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Primary and secondary prevention of colorectal cancer: An evidence- based review

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Family medicine and Community Health 2017年第1期5卷 78-84页

作者： Sandra j.Gonzalez maria C.mejia de Grubb Robert S.levine Department of Family and Community medicine Baylor College of MedicineHoustonTXUSA

Colorectal cancer (CRC) is a common cancer that affects one in three men and one in four women worldwide. Late-stage detection is associated with significantly lower 5-year survival rates. Although it is well established that CRC mortality rates have decreased in the past several decades, adoption of routine screening continues to lag behind screening for other common cancers such as cervical and breast cancer. The decrease in overall rates has been attributed, in part, to improved primary and secondary prevention efforts, including smoking prevention and cessation programs, nutritional counseling, and the use of evidence-based screening protocols, as well as access to better treatment. Despite the increased screening rates, it is estimated that at least one-third of eligible people do not receive appropriate screening. The objective of this review is to describe the current epidemiology of CRC and to demonstrate effective primary and secondary prevention strategies for the primary care provider.

关键词： Colorectal cancer adenocarcinoma modifiable risk factors primary prevention secondary prevention primary care

T cells from induced and spontaneous models of SLE recognize a common T cell epitope on β2-glycoprotein Ⅰ

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Cellular & molecular Immunology 2019年第8期16卷 685-693页

作者： David Salem Rebecca Subang masataka Kuwana jerrold S.levine joyce Rauch Division of Rheumatology Department of MedicineResearch Institute of the McGill University Health CentreMontrealQCCanada Department of Allergy and Rheumatology Nippon Medical SchoolGraduate School of MedicineTokyoJapan Section of Nephrology Department of MedicineUniversity of Illinois at ChicagoChicagoILUSA Section of Nephrology Department of MedicineJesse Brown Veterans Affairs Medical CenterChicago IL USA

Systemic lupus erythematosus is a prototypic model for B-cell epitope spread in *** to numerous molecularly distinct self-antigens emerge in a sequential manner over several years,leading to disease *** the earliest autoantibodies to appear are those targeting phospholipid-binding proteins,particularlyβ2-glycoprotein Ⅰ.Notably,mice immunized with β2-glycoprotein Ⅰ and lipopolysaccharide develop a strong T cell response to β2-glycoprotein Ⅰ that is associated with autoantibody production and renal disease,similar to that seen in human *** we hypothesized that mice with murine systemic lupus erythematosus,whether induced or spontaneous,should have T cells that recognizeβ2-glycoprotein *** evaluated the response of splenic T cells from mice with induced(C57BL/6 and C3H/HeN)and spontaneous(mRL/lpr)systemic lupus erythematosus to peptides spanning the entire sequence of humanβ*** found that mice with induced and spontaneous systemic lupus erythematosus recognize a common T cell epitope(peptide 31;LYRDTAVFECLPQHAmFG)in domain Ⅲ ofβ2-glycoprotein I.β2GPI-reactive CD4^(+)T cells from the two models differed primarily in cytokine production:T cells from mice with induced SLE expressed IFN-γ,while T cells from mRL/lpr mice expressed both IL-17 and IFN-γ,indicating that IL-17-expressing T cells are not necessary for generating aβ2GPI-reactive T cell *** data suggest that the generation of aβ2-glycoprotein Ireactive T cell response is shared by both induced and spontaneous models of systemic lupus erythematosus and that this T cell response may mediate epitope spread to autoantibodies in both models.

关键词： β2-glycoprotein I T cells systemic lupus erythematosus autoantibodies mHC class II haplotypes

Nanostructured grinding wheels for ultra-precision engineering applications

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Nanotechnology and Precision Engineering 2021年第3期4卷 63-75页

作者： m.j.jackson Integrated Studies College of Technology and AviationKansas State UniversitySalinaKansas 67401USA

manufacturers face challenges when dealing with abrasives that lose roundness,wear excessively,and suffer from pitting of the surface of the grinding wheel that needs rectification using dressing *** abrasive grits manufactured by hybrid fusion processes and by sintering/extrusion/printing processes are found to reduce pitting quite *** phenomenon of wheel collapse is increasing and cycle times developed during the grinding of aerospace alloys are much smaller compared to using conventional *** paper reviews the phenomenon of wheel collapse induced by pitting and takes a critical look at the production and analysis of hybrid fused and printed/sintered abrasives.A mathematical analysis is carried out of the diffusion of primary and secondary phases due to mechanical and ultrasonic agitation with the aim of producing abrasive grits with improved strength and *** developments in extruded,printed,and sintered grits for use in precision grinding applications are critically *** paper concludes by explaining how such abrasives are used in practice by industrial manufacturers of high-precision products.

关键词： Nanotechnology Abrasives Alloys Finishing Grinding machining

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Health risk of whole body vibration in mining trucks during various operational conditions

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journal of Central South University 2017年第8期24卷 1808-1816页

作者： Rahimdel m.j mirzaei m Sattarvand j Hoseinie S.H Department of mining Engineering Sahand University of TechnologyTabriz ***Iran Department of mechanical Engineering Sahand University of TechnologyTabriz ***Iran Department of mining Engineering Isfahan University of TechnologyIsfahan ***Iran

mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RmS) of vertical vibrations. However, the effect of the payload is not considerable on the RmS. moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.

关键词： mining trucks operational conditions health risk whole body vibration

Surface morphology and impurity distribution of electron beam recrystallized silicon films on low cost substrates for solar cell absorber

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Rare metals 2006年第z1期25卷 195-200页

作者： GROmBALL F müLLER j Department of mikrosystemtechnik Technische Universitt Hamburg-Harburg Hamburg 21073 Germany

A line shaped electron beam recrystallised polycrystalline silicon film on the low cost substrate was investigated for the use of the solar cell absorber. The applied EB energy density strongly influences the surface morphology of the film system. Lower EB energy density results in droplet morphology and the rougher SiO2 capping layer due to the low fluidity. With the energy increasing, the capping layer becomes smooth and continuous and less and small pinholes form in the silicon film. Tungstendisilicide (WSi2) is formed at the interface tungsten/silicon but also at the grain boundaries of the silicon. Because of the fast melting and cooling of the silicon film, the eutectic of silicon and tungstendisilicide mainly forms at the grain boundary of the primary silicon dendrites. The SEm-EDX analysis shows that there are no chlorine and hydrogen in the area surrounding a pinhole after recrystallization because of outgassing during the solidification.

关键词： polycrystalline silicon film solar cell recrystallization energy surface morphology outgassing

Dynamic mechanical Relaxation in Bulk metallic Glasses:A Review

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journal of materials Science & Technology 2014年第6期30卷 523-545页

作者： j.C.Qiao j.m.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main （α） and secondary （β） relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α. and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation （i.e. compression and cold rolling）. Importantly, to analyze the atomic mobility in amorphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.

关键词： metallic glasses mechanical properties main relaxation Secondary relaxation Physical analysis

Use of silica nanopowder to accelerate CO_2 sorption by Ca(OH)_2

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Particuology 2013年第4期11卷 448-453页

作者： m.A.S.Quintanilla j.m.Valverde Faculty of Physics University of SevilleAvenida Reina Mercedes s/n

Promising technologies have recently emerged to capture CO2 from postcombustion flue gas and to enhance the production of hydrogen from natural gas by steam-methane reforming, on the basis of sorp- tion of CO2 by Ca-based powders. The rate of CO2 sorption on Ca-based powders is limited by both carbonation kinetics and transport of CO2 to unreacted sorption sites. Ca-based powders may exhibit cohesive aggregation, thus hindering gas-solids contact efficiency. In our work, we tested the sorption rate of powder samples prepared by dry mixing of a cohesive Ca（OH）2 powder with a silica nanopowder used as additive. The silica nanopowder serves to improve the dispersibility of Ca（OH）2. Consequently, when a CO2 enriched gas and the modified sorbent are brought into contact, the rate of CO2 sorption is enhanced in the initial fast phase of interest for practical applications.

关键词： FluidizationFine powdersCO2 sorptionNanoparticles

DIFFERENTIAL OPERATORS OF INFINITE ORDER IN THE SPACE OF RAPIDLY DECREASING SEQUENCES

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Acta mathematica Scientia 2016年第2期36卷 325-333页

作者： m.mALDONADO j.PRADA m.j.SENOSIAIN Department of mathematics Salamanca University

We consider the space of rapidly decreasing sequences s and the derivative operator D defined on it. The object of this article is to study the equivalence of a differential operator of infinite order; that is φ（D） =^∞∑k=0φkD^k.φk constant numbers an a power of ***, meaning, is there a isomorphism X （from s onto s） such that Xφ（D） = D^nX？. We prove that if φ（D） is equivalent to Dn, then φ（D） is of finite order, in fact a polynomial of degree n. The question of the equivalence of two differential operators of finite order in the space s is addressed too and solved completely when n = 1.

关键词： Ordinary differential operators sequence spaces operators on function spaces