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Wettability of silicon carbide ceramic by Al_2O_3/Dy_2O_3 and Al_2O_3/Yb_2O_3 systems

Journal of Rare Earths 2013年第6期31卷 634-638页

作者： J.A.da silva b.M.Moreschi G.C.R.Garcia S.Ribeiro Department of Materials Engineering (DEMAR) Engineering School of Lorena (EEL)Pólo Urbo IndustrialGleba AI6CP 11612608-970LorenaSPBrazil

Wettability is an important phenomenon in the liquid phase sintering of silicon carbide （SiC） ceramics. This work involved a study of the wetting of SiC ceramics by two oxide systems, Al2O3 /Dy2O3 and Al2O3 /Yb2O3, which have so far not been studied for application in the sintering of SiC ceramics. Five mixtures of each system were prepared, with different compositions close to their respective eutectic ones. Samples of the mixtures were pressed into cylindrical specimens, which were placed on a SiC plate and subjected to temperatures above their melting points using a graphite resistance furnace. The behavior of the melted mixtures on the SiC plate was observed by means of an imaging system using a CCD camera and the sessile drop method was employed to determine the contact angle, the parameter that measures the degree of wettability. The results of variation in the contact angle as a function of temperature were plotted in graphic form which showed that the curves displayed a fast decline and good spreading. All the samples of the two systems presented final contact angles of 40o to 10o indicating their good wetting on SiC in the argon atmosphere. The melted/solidified area and interface between SiC and melted/solidified phase were evaluated by scanning electron microscopy （SEM） and their crystalline phases were identified by X-ray diffraction （DRX）. The DRX analysis showed that Al2O3 and RE2O3 reacted and formed the Dy3Al5O12 （DyAg） and Yb3Al5O12 （YbAg） phases. The results indicated that the two systems had a promising potential as additives for the sintering of SiC ceramics.

关键词： liquid-phase sintering silicon carbide rare earth oxide wettability contact angle

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Effects of lime addition on geotechnical properties of sedimentary soil in Curitiba,brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 188-194页

作者： Jair A.baldovino Eclesielter b.Moreira wagner Teixeira Ronaldo L.S.Izzo Juliana L.Rose Department of Civil Construction Federal University of Technology-Paraná Campus Curitiba

The soil of the Guabirotuba geological formation（Paraná basin, brazil） has physico-mechanical properties which are not suitable for its utilization in pavement construction, in protection of hillsides and slopes, or as shallow foundation support. Treatment of this soil by lime addition would improve its usability. The present context intends to determine the ratio between the splitting tensile strength（q;）and the unconfined compressive strength（q;） of clayey soil in the metropolitan region of Curitiba City,which has been treated with different lime contents and curing times. The control parameters evaluated include lime content（L）, curing time（t）, moisture content（w）, and ratio of porosity to volumetric lime content（η/L;）. It was observed that the q;/q;ratio is between 0.17 and 0.2 in relation to the curing time,and an exponential relation exists between them. Meanwhile, the unconfined compressive strength of lime-treated soil was found to be approximately four times the initial value.

关键词： Clayey soil stabilization Soil strength Lime-soil mixture Curing time

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Single-cell transcriptomes and runx2b-/- mutants reveal the genetic signatures of intermuscular bone formation in zebrafish

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National Science Review 2022年第11期9卷 97-107页

作者： Chun-Hong Nie Shi-Ming Wan Yu-Long Chen Ann Huysseune Ya-Ming Wu Jia-Jia Zhou Alexandre wagner silva Hilsdorf Wei-Min Wang Paul Eckhard Witten Qiang Lin Ze-Xia Gao College of Fisheries Key Lab of Freshwater Animal BreedingMinistry of Agriculture and Rural AffairsKey Lab of Agricultural Animal GeneticsBreeding and Reproduction of Ministry of EducationEngineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt Ministry of Education Huazhong Agricultural University Hubei Hongshan Laboratory CAS Key Laboratory of Tropical Marine bio-Resources and Ecology South China Sea Institute of Oceanology Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of Sciences Department of biology Ghent University Unit of biotechnology University of Mogi das Cruzes Guangdong Laboratory for Lingnan Modern Agriculture

Intermuscular bones(Ibs) are mineralized spicules, present in the myosepta of many, but not all, teleost species. Ibs are often small and sharp, and they consequently limit how the fish can be processed; the Ibs may cause injury or trauma if lodged in consumers’ throats or mouths, and therefore affect the appeal of the fish to many consumers. The development of Ibs in teleosts is still not fully understood and the molecular basis of Ib development remains to be established. Here, the characteristics of Ib tissue are evaluated based on single-cell transcriptomics in wild-type zebrafish. The analysis defined 18 distinct cell *** trajectories showed that Ibs are derived from tendons and that a core tendon-osteoblast cell lineage is related to Ib formation. In particular, the functions of 10 candidate genes were evaluated via CRISPR-Cas9 mutants. Among those, runx2b-/-mutants completely lost Ibs, while swimming performance, growth and bone mineral density were not significantly different from runx2b+/+*** single-cell RNA sequencing(sc RNA-seq) analysis in runx2b-/-and runx2b+/+zebrafish revealed the role of osteoblasts in Ib formation. In addition, differentially expressed genes were enriched in the transforming growth factor β/bone morphogenetic protein(TGF-β/bMP) pathway after runx2b deletion. This study provides evidence for the crucial role of runx2b regulation in Ib formation. Genetic breeding can target runx2b regulation and generate strains of commercial fish species without Ibs, which can improve the safe consumption and economic value of many farmed fish species.

关键词： teleosts zebrafish intermuscular bones scRNA-seq tendon-osteoblast cell lineage runx2b genetic breeding

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Cubosome nanoparticles for enhanced delivery of mitochondria anticancer drug elesclomol and therapeutic monitoring via sub-cellular NAD(P) H multi-photon fluorescence lifetime imaging

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Nano Research 2019年第5期12卷 991-998页

作者： Ana R.Faria Oscar F.Silvestre Christian Maibohm Ricardo M.R.Adao bruno F.b.silva Jana b.Nieder Department of Nanophotonics Ultrafast Bio- and Nanophotonics GroupINL - International Iberian Nanotechnology LaboratoryAv.Mestre Jose Veiga s/n4715-330 BragaPortugal Department of Life Sciences INL-International Iberian Nanotechnology LaboratoryAv.Mestre Jose Veiga s/n4715-330 BragaPortugal

Elesclomol (ELC) is an anticancer drug inducing mitochondria cytotoxicity through reactive oxygen ***,for the first time,we encapsulate the poorly water soluble ELC in monoolein-based cubosomes stabilized with Pluronic *** uptake and nanocarrier accumulation close to the mitochondria with sub-micrometer distance is identified via three-dimensional (3D) confocal microscopy and edge-to-edge compartment *** monitor the therapeutic effect of the ELC nanocarrier,we apply for the first time,label-free time-lapse multi-photon fluorescence lifetime imaging microscopy (MP-FLIM) to track NAD(P)H cofactors with sub-cellular resolution on live cells exposed to an anticancer *** in vitro cytotoxicity is verified when loading the pre-complexed ELC with copper (ELC-Cu).Importantly,for equivalent copper concentration,cubosomes loaded with ELC-Cu show higher cytotoxicity compared to the free *** novel nanocarrier shows promising features for systemic ELC-Cu administration,and furthermore we establish the MP-FLIM technique for the assessment of anticancer drug delivery systems.

关键词： cubosomes mitoch on dria reactive oxyge n species elesclomol NAD(P)H fluoresce nee lifetime anticancer therapy

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Finite element model with imposed slip surfaces for earth mass safety evaluation

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Journal of Central South University 2014年第9期21卷 3627-3638页

作者： Nuno ARAUJO Gaspar J.MACHADO Julio b.MARTINS Hugo M.R.D.silva C-TAC Territory Environment and Construction Research Centre School of EngineeringUniversity of Minho Guimaraes 4800-058 Portugal Centre of Mathematics School of Sciences University of Minho Guimaraes 4800-058 Portugal

The study of earth masses requires numerical methods that provide the quantification of the safety factor without requiring detrimental assumptions. For that, equilibrium analysis can perform fast computations but require assumptions that limit its potentiality. Limit analysis does not require detrimental assumptions but are numerically demanding. This work provides a new approach that combines the advantage of both the equilibrium method and the limit analysis. The defined hybrid model allows probabilistic analysis and optimization approaches without the assumption of interslice forces. It is compared with a published case and used to perform probabilistic studies in both a homogeneous and a layered foundation. Analyses show that the shape of the density probability functions is highly relevant when computing the probability of failure, and soil elasticity hardly affects the safety of factor of the earth mass.

关键词： slope stability probabilistic methods reliability genetic algorithms safety factor

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Use of shear wave elastography for the diagnosis and follow-up of biliary atresia: A meta-analysis

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World Journal of Gastroenterology 2022年第32期28卷 4725-4739页

作者： Ellen S wagner Hussien Ahmed H Abdelgawad Meghan Landry belal Asfour Mark b Slidell Ruba Azzam Pediatric Gastroenterology Hepatologyand NutritionThe University of Chicago MedicineComer Children’s HospitalChicagoIL 60637United States Department of Medicine Zagazig UniversityZagazig 44511EgyptEgypt Department of Pediatrics The University of Chicago MedicineComer Children’s HospitalChicagoIL 60637United States Graduate School of Professional Education-biomedical Informatics University of ChicagoChicagoIL 60637United States Department of Surgery The University of Chicago MedicineComer Children’s HospitalChicagoIL 60637United States

bACKGROUND Timely differentiation of biliary atresia(bA)from other infantile cholestatic diseases can impact patient ***,non-invasive staging of fibrosis after Kasai hepatoportoenterostomy has not been widely *** wave elastography is an ultrasound modality that detects changes in tissue *** authors propose that the utility of elastography in bA can be elucidated through meta-analysis of existing *** To assess the utility of elastography in:(1)bA diagnosis,and(2)post-Kasai fibrosis *** A literature search identified articles that evaluated elastography for bA diagnosis and for post-Kasai *** studies met criteria for meta-analysis:Eleven for diagnosis and nine for follow-up *** diagnostic odds ratio(DOR),sensitivity,and specificity of elastography were calculated through a random-effects model using Meta-DiSc *** Mean liver stiffness in bA infants at diagnosis was significantly higher than in non-bA,with overall DOR 24.61,sensitivity 83%,and specificity 79%.Post-Kasai,mean liver stiffness was significantly higher in bA patients with varices than in patients without,with DOR 16.36,sensitivity 85%,and specificity 76%.Elastography differentiated stage F4 fibrosis from F0-F3 with DOR of 70.03,sensitivity 96%,and specificity 89%.Elastography also differentiated F3-F4 fibrosis from F0-F2 with DOR of 24.68,sensitivity 85%,and specificity 81%.CONCLUSION Elastography has potential as a non-invasive modality for bA diagnosis and surveillance *** paper’s limitations include inter-study method heterogeneity and small sample ***,standardized,multi-center studies are recommended.

关键词： biliary atresia Cholestasis Hepatic portoenterostomy Fibrosis Esophageal and gastric varices Elasticity imaging techniques

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Functional and structural changes in internal pudendal arteries underlie erectile dysfunction induced by androgen deprivation

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Asian Journal of Andrology 2017年第5期19卷 526-532页

作者： Rheure Alves-Lopes Karla b Neves Marcondes Ab.silva Vania C Olivon Silvia G Ruginsk Jose Antunes-Rodrigues Leandra NZ Ramalho Rita C Tostes Fernando silva Carneiro Department of Pharmacology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Physics and Chemistry Faculty of Pharmaceutical Sciences of Ribeirao Preto University of Sao Paulo Ribeirao Preto SP Brazil Department of Physiological Sciences Biomedical Sciences InstituteFederal University of Alfenas Alfenas MG Brazil Department of Physiology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Pathology and Legal Medicine Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil

Androgen deficiency is strongly associated with erectile dysfunction （ED）. Inadequate penile arterial blood flow is one of the major causes of ED. The blood flow to the corpus cavernosum is mainly derived from the internal pudendal arteries （IPAs）; however, no study has evaluated the effects of androgen deprivation on IPA＇s function. We hypothesized that castration impairs IPAs reactivity and structure, contributing to ED. In our study, Wistar male rats, 8-week-old, were castrated and studied 30 days after orchiectomy. Functional and structural properties of rat IPAs were determined using wire and pressure myograph systems, respectively. Protein expression was determined by Western blot and immunohistochemistry. Plasma testosterone levels were determined using the IMMULITE 1000 Immunoassay System. Castrated rats exhibited impaired erectile function, represented by decreased intracavernosal pressure/mean arterial pressure ratio. IPAs from castrated rats exhibited decreased phenylephrine- and electrical field stimulation （EFS）-induced contraction and decreased acetylcholine- and EFS-induced vasodilatation. IPAs from castrated rats exhibited decreased internal diameter, external diameter, thickness of the arterial wall, and cross-sectional area. Castration decreased nNOS and α-actin expression and increased collagen expression, p38 （Thr180/ryr182） phosphorylation, as well as caspase 3 cleavage. In conclusion, androgen deficiency is associated with impairment of IPA reactivity and structure and increased apoptosis signaling markers. Our findings suggest that androgen deficiency-induced vascular dysfunction is an event involving hypotrophic vascular remodeling of IPAs.

关键词： androgen castration internal pudendal artery

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电动汽车悬架运动学优化方法

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同济大学学报（自然科学版） 2022年第S1期50卷 1-9页

作者： Y HUANG J KÖPLER A wagner J NEUbECK b JACObSON 查尔默斯理工大学瑞典哥德堡41296 斯图加特大学汽车工程学院(IFS) 德国斯图加特70569

电池电动汽车(bEV)的主要挑战之一是续航里程是否足够,因此在任何最近的车辆概念中,最大化的电池体积是合乎需要的。悬架作为最大的电动汽车子系统之一,对这一点有着重要的影响。本研究目的是使用自动化方法进行悬架开发,主要是引入一... 详细信息

电池电动汽车(bEV)的主要挑战之一是续航里程是否足够,因此在任何最近的车辆概念中,最大化的电池体积是合乎需要的。悬架作为最大的电动汽车子系统之一,对这一点有着重要的影响。本研究目的是使用自动化方法进行悬架开发,主要是引入一种新的可转向后悬架概念与电力推进系统,即从配备内燃机(ICE)的传统汽车开始,开发一种悬架,以满足纯电动汽车的新装配要求,同时保持有关驾驶动力学的典型要求。悬架概念是为具有大电池尺寸的高级汽车而优化的,此外还考虑了先进的主动系统,如空气弹簧和大转向角的主动后轮转向。该概念还提出了一种具有良好调整运动学性能的封装解决方案,符合原始设备制造商的调整理念。为解决由此产生的高复杂性,使用了新开发的方法,即运动学优化是用一种创新的方法完成的,该方法根据给定的要求自动提出新的硬点。在设计中,使用简化模型来表示复杂零件的形状,因此可以从包装的角度自动判断运动学概念是否可行。结果表明,新的悬架概念可以处理具有挑战性的装配问题和复杂的运动学要求。

关键词：电动汽车(bEV) 开发过程运动学包装

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Mechanical behavior of iron ore tailings under standard compression and extension triaxial stress paths

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1883-1894页

作者： Alexia Cindy wagner João Paulo de Sousa silva João Vítor de Azambuja Carvalho Ana Luisa Cezar Rissoli Pedro Pazzoto Cacciari Helder Mansur Chaves Hugo Carlos Scheuermann Filho Nilo Cesar Consoli Universidade Federal do Rio Grande do Sul Porto Alegre90035-190Brazil Mineral Development Centre Vale S.A.Santa Luzia33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealMontrealH3C 3A7Canada

The disposal of mining tailings has increasingly focused on the use of dry *** structures offer more security since they use filtered and compacted *** of the construction method and the heights achieved,the material that compounds the structure can be subjected to different stress paths along the failure *** theoretical framework considered in the design of these structures generally is the critical state soil mechanics(CSSM).However,the data in the literature concerning the uniqueness of critical state line(CSL)is still controversial as the soil is subjected to different stress *** respect to tailings,this question is even more *** paper studies two tailings with different gradings due to the beneficial processes over extension and compression paths.A series of drained and undrained triaxial tests was conducted over a range of initial densities and stress *** the q-p'plane,different critical stress ratio(M)values were obtained for compression and extension stress ***,the critical state friction angle is very similar with a slightly higher critical state friction angle for extension *** stress path dependent CSLs were obtained in the n-lnp0 plane with the extension tests below the CSL defined in *** the fines content,the studied tailings presented very similar M and critical state friction angle ***,the fines content af-fects the volumetric behavior of the studied tailings and the CSLs on the n-lnp0 plane shift downwards with the increasing fines content for compression and extension *** relation to dilatancy analysis,the fines content did not present an evident influence on the dilatancy of the ***,different values of mean stress ratio N were obtained between compression and extension tests and can corroborate the existence of non-unique CSLs for these materials.

关键词： Iron ore tailings(IOTs) Dry stacking Critical state soil mechanics Extension tests Stress path

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Asphaltene aggregation studied by molecular dynamics simulations:role of the molecular architecture and solvents on the supramolecular or colloidal behavior

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Petroleum Science 2019年第3期16卷 669-684页

作者： H.Santos silva A.Alfarra G.Vallverdu D. begue b.bouyssiere I.baraille Institut des Science Analytiques et Physico-Chimie pour l'Environnement et les Materiaux UMR 5254 CNRS/Univ Pau and Pays Adour 64000 Pau France Total Research and Technology BP 2776700 Gonfreville Harfleur France Joint Laboratory C2MC: Complex Matrices Molecular Characterization Total Research and Technology BP 2776700 Gonfreville Harfleur France

Asphaltene aggregation is a subject under vivid discussion:There are several parameters one needs to determine before its behavior can be mastered and better target solutions can be *** nature of asphaltene aggregation(colloidal or supramolecular)and the role of solvents and their mixtures are among the least understood parameters in asphaltene *** paper addresses molecular dynamic simulations to correlate the aggregation properties of asphaltenes,their molecular structure and the concentration of these *** show that the formation of the nanoaggregate depends,primarily,on the size of the conjugated core and on the eventual presence of polar groups capable of forming *** on the conjugated core do not change their shape or type of aggregation but may induce stronger π-π *** macroaggregation formation depends upon the length of the lateral chains of asphaltenes and also on the presence of polar groups at its ***,n-heptane and water may interact selectively with asphaltenes in function of their molecular *** this fact and the aggregation behavior observed,we advocate toward the assumption that a colloidal behavior of asphaltenes might be a particular case of a more general model,based on a supramolecular description.

关键词： Asphaltenes Molecular dynamics Aggregation Heavy oil

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