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Communications in Computational Physics 2022年第3期31卷 816-868页

作者： jean-Michel Tucny David Vidal Sebastien Leclaire francois Bertrand Mechanical Engineering Department Polytechnique MontralP.O.Box 6079Stn.CVMontrealQCCANADAH3C 3A7 Chemical Engineering Department Polytechnique MontralP.O.Box 6079Stn.CVMontrealQCCANADAH3C 3A7

The simulation of rarefied gasflows through complex porous media is chal-lenging due to the tortuousflow pathways inherent to such *** Lattice Boltzmann method(LBM)has been identified as a promising avenue to solveflows through complex geometries due to the simplicity of its scheme and its high parallel computational *** has been proposed to model the stress-strain relationship with the extended Navier-Stokes equations rather than attempting to directly solve the Boltzmann ***,a regularization technique is required tofilter out non-resolved higher-order components with a low-order velocity *** slip boundary conditions(BCs)have been proposed for the non-regularized multiple relaxation time LBM(MRT-LBM)for planar geometries,previous slip BCs have never been verified extensively with the regularization *** this work,following an extensive literature review on the imposition of slip BCs for rarefiedflows with the LBM,it is proven that earlier values for kinetic parameters developed to impose slip BCs are inaccurate for the regularized MRT-LBM and differ between the D2Q9 and D3Q15 *** error was eliminated for planarflows and good agreement be-tween analytical solutions for arrays of cylinders and spheres was found with a wide range of Knudsen numbers.

关键词： Lattice Boltzmann method(LBM) boundary condition(BC) rarefiedflow nonplanar geometry

The local contribution to the microwave background radiation

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Research in Astronomy and Astrophysics 2015年第4期15卷 461-474页

作者： jean-Claude Pecker Jayant V.Narlikar francois Ochsenbein Chandra Wickramasinghe College de France Inter-University Centre for Astronomy and Astrophysics Centre de Donnees astronomiques de Strasbourg (CDS) Observatoire de Strasbourg11rue de l’Universite 67000 StrasbourgFrance Buckingham Centre for Astrobiology University of Buckingham

The observed microwave background radiation （MBR） is commonly in- terpreted as the relic of an early hot universe, and its observed features （spectrum and anisotropy） are explained in terms of properties of the early universe. Here we describe a complementary, even possibly alternative, interpretation of MBR, first proposed in the early 20th century, and adapt it to modern observations. For example, the stellar Hipparcos data show that the energy density of starlight from the Milky Way, if suit- ably thermalized, yields a temperature of ~2.81 K. This and other arguments given here strongly suggest that the origin of MBR may lie, at least in a very large part, in re-radiation of thermalized galactic starlight. The strengths and weaknesses of this alternative radical explanation are discussed.

关键词： Galaxy: stellar content -- (cosmology:) cosmic microwave background-- cosmology: observations

Droplet digital PCR for quantification of ITGA6 in a stool mRNA assay for the detection of colorectal cancers

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World Journal of Gastroenterology 2017年第16期23卷 2891-2898页

作者： Elizabeth Herring Shigeru Kanaoka éric Tremblay jean-francois Beaulieu Laboratory of Intestinal Physiopathology Department of Anatomy and Cell BiologyFaculty of Medicine and Health SciencesUniversitéde SherbrookeSherbrookeQC J1H5N4Canada Department of Gastroenterology Hamamatsu Medical CenterNaka-kuHamamatsu 432-8580Japan

AIM To investigate the use of droplet digital polymerase chain reaction(dd PCR) for detecting host m RNA markers in stools as a non-invasive test for colorectal cancer *** dd PCR and quantitative PCR were compared side by side for their performance in the detection of ITGA6 and ITGA6 A transcripts in stool samples obtained from patients with various types of colorectal lesions(advanced adenomas and stage Ⅱ-Ⅳ colorectal cancers) and control(patients displaying no pathological findings) using duplex Taq Man reactions for both methods. ITGA6 and ITGA6 A were chosen for this proof-of-concept study based on their relative medium and low abundance in stool samples, respectively, as established in a previous *** We found that the dd PCR and q PCR methods per-formed equally well in this Taq Man duplex assay for the detection of ITGA6 and ITGA6 A transcripts in stools of patients with colorectal lesions. For ITGA6, receiver operating characteristic(ROC) curve analysis showed comparable areas under the curve of 0.91(P < 0.0001) and 0.89-0.90(P < 0.0001) for the prediction of advanced adenomas and colorectal cancers, respectively. ITGA6 A, which was detected at very low levels in control patients, was found to be significantly elevated(over 40 times) in stage Ⅱ and Ⅲ colorectal cancers(P < 0.0002). Comparison of the two sets of data revealed a strong correlation of the copy numbers obtained by dd PCR and q PCR for both ITGA6 and ITGA6 *** We found that ITGA6 and ITGA6 A detection in stools of patients with colorectal cancers with dd PCR is comparable to that of q PCR using Taq Man assays.

关键词： Colorectal cancer Advanced adenoma Non-invasive screening Biomarker mRNA

Medical management of metabolic and cardiovascular complications after liver transplantation

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World Journal of Gastroenterology 2020年第18期26卷 2138-2154页

作者： Chiara Becchetti Melisa Dirchwolf Vanessa Banz jean-francois Dufour Hepatology Department of Visceral Surgery and MedicineInselspitalUniversity Hospital BernBern CH-3008Switzerland Department of Biomedical Research University of BernBern CH-3008Switzerland Hepatology Hepatobiliary Surgery and Liver Transplant UnitHospital Privado de RosarioRosario S2000GAPSanta FeArgentina Department of Visceral Surgery and Medicine InselspitalUniversity Hospital BernBern CH-3008Switzerland Department of Clinical Research University of BernBern CH-3008Switzerland

Liver transplantation represents the only curative option for patients with endstage liver disease,fulminant hepatitis and advanced hepatocellular *** though major advances in transplantation in the last decades have achieved excellent survival rates in the early post-transplantation period,long-term survival is hampered by the lack of improvement in survival in the late post transplantation period(over 5 years after transplantation).The main etiologies for late mortality are malignancies and cardiovascular *** latter are increasingly prevalent in liver transplant recipients due to the development or worsening of metabolic syndrome and all its components(arterial hypertension,dyslipidemia,obesity,renal injury,etc.).These comorbidities result from a combination of pre-liver transplant features,immunosuppressive agent side-effects,changes in metabolism and hemodynamics after liver transplantation and the adoption of a sedentary *** this review we describe the most prevalent metabolic and cardiovascular complications present after liver transplantation,as well as proposing management strategies.

关键词： Solid organ transplantation Hypertension New-onset diabetes after transplantation Obesity Orthotopic liver transplantation Post-transplantation metabolic syndrome

Land cover mapping applications with MODIS:a literature review

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International Journal of Digital Earth 2012年第1期5卷 63-87页

作者： Tziztiki J.Garcıa-Mora jean-francois Mas Everett A.Hinkley Centro de Investigaciones en Geografı´a Ambiental Universidad Nacional Autonoma de Mexico(UNAM)Antigua Carretera a Patzcuaro No.8701Col.Ex-Hacienda de San Josede La HuertaC.P.58190MoreliaMichoacanMexico National Remote Sensing Program Manager USDA Forest Service1601 N.Kent Street/Suite 500ArlingtonVA 22209USA

Land use/land cover monitoring and mapping is crucial to efficient management of the land and its *** the late 1980s increased attention has been paid to the use of coarse resolution optical *** Moderate Resolution Imaging Spectroradiometer(MODIS)has features,which make it particularly suitable to earth characterization *** has 10 products dedicated mainly to land cover characterization and provides three kinds of data:angular,spectral and *** data also includes information about the data quality through the‘Quality Assessment’*** this paper,we review how MODIS data are used to map land cover including the preferred MODIS products,the preprocessing and classification approaches,the accuracy assessment,and the results obtained.

关键词： MODIS mapping image processing classification,accuracy land use/land cover

Forecasting pest risk level in roses greenhouse:Adaptive neuro-fuzzy inference system vs artificial neural networks

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Information Processing in Agriculture 2021年第3期8卷 386-397页

作者： Ahmad Tay Frederic Lafont jean-francois Balmat University of Toulon LISUMR CNRS 7020Bt XCS 6058483041 Toulon cedex 9France

The purpose of this study is to establish a system for the prediction of the pests’risk level in a roses greenhouse by applying Artificial Neural Networks(ANNs)and an Adaptive Neuro-Fuzzy Inference System(ANFIS).Pests in roses greenhouses are known to be fatal to plants if not detected at a premature *** detection could avoid huge agronomic and eco-nomic ***,it could be a difficult task to *** complexities arising from the interactions between variables influencing the development could be a barrier to fulfill the previously mentioned *** output of the developed system represents the next day?s risk level of Western flower Thrips(WFT)(Frankliniella occidentalis)in a roses *** explanatory variables,such as internal temperature,internal humidity,today’s pest risk level and human intervention have been considered for this *** main contributions of this study are three fold;providing a daily estimate WFT risk level,reduc-ing the use of pesticides and finally mitigating yield *** obtained results were com-pared to each other and to real *** performance of the models has been evaluated by 3 statistical *** results showed conspicuous performance of both models,indicating their efficiency for pest *** novelty associated with the sys-tem is the creation of decision support tool for daily risk assessment of *** on a small number of variables,this system is a monitoring tool which contributes to help farm-ers early reveal warning *** addition,this is a first attempt to employ ANNs and ANFIS for the prediction of WFT。

关键词： Decision making Artificial neural networks ANFIS Risk assessment Integrated pest management

Comparison of airway resistance measurements by the forced oscillation technique and the interrupter technique for detecting chronic obstructive pulmonary disease in elderly patients

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Chinese Medical Journal 2005年第22期118卷 1921-1924页

作者： GUO Yan-fei SUN Tie-ying francois Herrmann jean-Paul Janssens Division of Pulmonary Medicine Beijing Hospital Beijing 100730China Department of Rehabilitation and Geriatrics Geneva University Hospital Geneva Switzerland Division of Pulmonary Medicine Geneva University HospitalGeneva Switzerland

Rulmonary function tests provide an objective means to verify ventilatory dysfunction and to estimate its severity in respiratory disorders. Measurement of forced expiratory volume in 1 second （FEV1） and forced vital capacity （FVC） is considered to be the basic tests for the assessment of airway obstruction. Although they are useful diagnostically and prognostically, the results of FEV1 and FVC are strongly dependent on the cooperation of the patient. Lack of collaboration is particularly present in elderly patients because of mood alterations, fatigability or cognitive impairment. The forced oscillation technique （FOT） and the interrupter resistance technique are the two methods of measuring respiratory resistance during tidal breathing, they are of special interest because both of them are noninvasive, requires minimal cooperation, takes little time and can be easily repeated, especially in children and elderly subjects who cannot accomplish forced expiratory maneuvers in a reproducible manner.

关键词： forced oscillation technique· interrupter technique·chronic obstructive pulmonary disease

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When lifestyles sign

Hepatobiliary Surgery and Nutrition 2019年第1期8卷 69-71页

作者： Maria Guarino Cedric Bovet jean-francois Dufour Hepatology Department for BioMedical ResearchUniversity of BernBernSwitzerland Gastroenterology Department of Clinical Medicine and SurgeryUniversity of Naples“Federico II”NaplesItaly University Institute of Clinical Chemistry InselspitalUniversity of BernBernSwitzerland University Clinic of Visceral Surgery and Medicine Inselspital BernBernSwitzerland

Nonalcoholic fatty liver disease(NAFLD)has a global prevalence of 25%,reflecting the global epidemic of obesity and diabetes(1).The onset and development of NAFLD are closely associated with dietary habits and lifestyle;consequently,lifestyle modifications including weight loss,increased physical activity,and dietary changes remain the treatment of choice for *** when drugs to treat non-alcoholic steatohepatitis will be available,lifestyle changes will remain an essential component of the therapeutic plan of these *** the last years,a strong association between lifestyle and hepatocellular carcinoma(HCC)has become evident(2-4).In patients with NAFLD,the annual incidence of HCC is 0.44 per 1,000 person/year and almost 50%of cases develops in a non-cirrhotic liver resulting in a diagnosis at an advanced stage with a worse prognosis(1,5).Nonetheless,the high prevalence of NAFLD with the relatively low risk for HCC makes a surveillance program cost-ineffective in non-cirrhotic patients(6).

关键词： NAFLD diagnosis drugs

Iron- and Ferritin-Dependent Reactive Oxygen Species Distribution： Impact on Arabidopsis Root System Architecture

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Molecular Plant 2015年第3期8卷 439-453页

作者： Guilhem Reyt Soukaina Boudouf Jossia Boucherez Frédéric Gaymard jean-francois Briat Biochimie et Physiologie Moléculaire des Plantes Centre National de la Recherche Scientifique Institut National de la Recherche Agronomique Université Montpellier 2 SupAgro. Bat 7 2 place Viala 34060 Montpellier Cedex 1 France present address: Institute of Biological and Environmental Sciences University of Aberdeen Cruickshank Building St Machar Drive Aberdeen Scotland AB243UU UK

Iron （Fe） homeostasis is integrated with the production of reactive oxygen species （ROS）, and distribution at the root tip participates in the control of root growth. Excess Fe increases ferritin abundance, enabling the storage of Fe, which contributes to protection of plants against Fe-induced oxidative stress. AtFerl and AtFer3 are the two ferritin genes expressed in the meristematic zone, pericycle and endodermis of theAra- bidopsis thaliana root, and it is in these regions that we observe Fe stained dots. This staining disappears in the triple ferl-3-4 ferritin mutant. Fe excess decreases primary root length in the same way in wild-type and in ferl-3-4 mutant. In contrast, the Fe-mediated decrease of lateral root （LR） length and density is enhanced in ferl-3-4 plants due to a defect in LR emergence. We observe that this interaction between excess Fe, ferritin, and root system architecture （RSA） is in part mediated by the H_2O_2/O2·^- balance between the root cell proliferation and differentiation zones regulated by the UPB1 transcription factor. Meristem size is also decreased in response to Fe excess in ferritin mutant plants, implicating cell cycle arrest mediated by the ROS-activated SMR5/SMR7 cyclin-dependent kinase inhibitors pathway in the interaction between Fe and RSA.

关键词： roots development oxidative stress reactive oxygen species balance iron ferritins

Preparation and Stability of SiO2/TiO2/Al2O3 Nanofluids Based Water/Ethylene Glycol

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Preparation and Stability of SiO2/TiO2/Al2O3 Nanofluids Base...

作者： Ninsemon jean francois Dazihem 西南石油大学

学位级别：硕士

随着科学技术的进步,换热设备的换热强度和换热负荷急剧增加,大量数据服务器在全国范围内的普及,设备温度精确控制的需求对其传热和散热性能提出了更高的要求。在此背景下,改善换热器的工质是解决这一问题的有效途径。因此,科学家们考... 详细信息

随着科学技术的进步,换热设备的换热强度和换热负荷急剧增加,大量数据服务器在全国范围内的普及,设备温度精确控制的需求对其传热和散热性能提出了更高的要求。在此背景下,改善换热器的工质是解决这一问题的有效途径。因此,科学家们考虑利用纳米流体代替水作为热交换器的工质。纳米流体是一种革命性的传热介质,它将非金属颗粒以一定比例混合到液体中。较水而言,纳米流体在导热性上具有显著的优势。然而,纳米流体在实际运用中实现稳定是一个挑战。本研究的主要目标是提高纳米流体的稳定性。在本工作中,纳米流体的制备采用两步法,以水和乙二醇为基础液。实验研究了二氧化硅(SiO2)、二氧化钛(TiO2)和氧化铝(Al2O3)纳米流体的制备及其稳定性。考察了乙二醇体积分数、分散剂种类与浓度、纳米粒子质量分数,超声分散时间等因素的影响。通过静置沉降,粒度分析和分光光度法等方法分析纳米流体的稳定性。最后使用Haaker旋转流变仪评估温度对所制备的纳米流体粘度的影响。主要研究结果如下:在制备二氧化硅(SiO2)纳米流体时发现,聚乙烯吡络烷酮(PVP)较阿拉伯树胶(GA)更适用于SiO2-水-乙二醇基纳米流体的分散剂。对于0.2 wt%的SiO2纳米流体,当PVP质量分数为0.4 wt%;乙二醇体积分数为20%,超声时间为30 min时,为制备SiO2-水-乙二醇基纳米流体的最佳条件。在20℃～60℃加热过程中,SiO2-水-乙二醇基纳米流体的粘度最高为2.8mpa·s,最低为1.4 mpa·s。对于TiO2纳米流体,GA较PVP更为适用于TiO2-水-乙二醇基纳米流体的分散剂。对于0.08 wt%的TiO2纳米流体,当GA质量分数为0.08 wt%;乙二醇体积分数为35%,超声为60 min时,为制备TiO2-水-乙二醇基纳米流体的最佳条件。在20℃～60℃加热过程中,TiO2-水-乙二醇基纳米流体粘度最低达1.5mpa·s.对于γ-三氧化二铝(γ-Al2O3)纳米流体,乙二醇体积分数为35%时更适用于γ-A12O3-水-乙二醇基纳米流体的制备;质量分数为0.2%的阿拉伯树胶(GA)可有效提高0.1 wt%的γ-Al2O3纳米颗粒在水-乙二醇基液中的分散稳定性;超声30 min即可改善γ-A1203-水-乙二醇纳米流体的稳定性。在20℃～60℃加热过程中,Al2O3乙二醇基纳米流体粘度最低达0.97mpa·s,所制备的纳米流体可适合用于流动换热。

关键词：纳米流体制备稳定性 SiO2/TiO2/Al2O3纳米流体水/乙二醇