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Particle Characteristics and Metal Release From Natural Rutile (TiO<sub>2</sub>) and Zircon Particles in Synthetic Body Fluids

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Journal of Biomaterials and Nanobiotechnology 2012年第1期3卷 37-49页

作者： yolanda Hedberg Jonas Hedberg Inger Odnevall Wallinder Division of Surface and Corrosion Science Department of Chemistry Royal Institute of Technology (KTH) Stockholm Sweden

Titanium oxide (rutile, TiO2) and zircon (ZrSiO4), known insoluble ceramic materials, are commonly used for coatings of implant materials. We investigate the release of zirconium, titanium, aluminum, iron, and silicon from different micron-sized powders of 6 powders of natural rutile (TiO2) and zircon (ZrSiO4) from a surface perspective. The investigation includes five different synthetic body fluids and two time periods of exposure, 2 and 24 hours. The solution chemicals rather than pH are important for the release of zirconium. When exceeding a critical amount of aluminum and silicon in the surface oxide, the particles seem to be protected from selective pH-specific release at neutral or weakly alkaline pH. The importance of bulk and surface composition and individual changes between different kinds of the same material is elucidated. Changes in material properties and metal release characteristics with particle size are presented for zircon.

关键词： Rutile Zircon Metal ion release Particles Surface analysis

Characterization of the Atmospheric Dynamics in Riobamba City Using the Chaos Theory

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Atmospheric and Climate Sciences 2015年第4期5卷 441-449页

作者： Arquímides Haro Cecilia Limaico yolanda Llosas Physics and Mathematics School Polytechnic School of Chimborazo Riobamba Ecuador Faculty of Engineering National University of Chimborazo Riobamba Ecuador Department of Automatic Control East University Santiago Cuba

Chaos studies all that is messy, disorganized and incoherent;mathematically the chaos is a dynamic system governed by nonlinear differential equations. Chaos has an unpredictable behavior;its dynamical is very sensitive to the initial conditions. Atypical chaotic system is the atmosphere;this limits the knowledge about its behavior;but with the advance in the computers, the results that are obtained with the chaos theory improved significantly;the description of atmosphera and its results have extended to other fields of the science, as the economy, health and others. The object of this work was to determine the atmospheric dynamics in the Riobamba city using the theory of chaos, with meteorological data of the meteorological station of the ESPOCH of one year (2010) of data that were processed with model TISEAN. The results determine a hyperchaotic system, according to the coefficients of Lyapunov.

关键词： Chaos Theory Atmospheric Variables Coefficients of Lyapunov Dynamics Entropy

Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1166-1179页

作者： Sebastián Díaz-López Jerónimo Jiménez-Castro Carlos Enrique Robles-Barraza Carlos Ayala-de Miguel Manuel chaves-Conde Medical Oncology Department Hospital Universitario ValmeSeville 41014AndalucíaSpain

Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic *** are composed of a neuroendocrine(NE)and a non-NE compo-nent in at least 30%of each *** non-NE component can include different histological combinations of glandular,squamous,mucinous and sarcomatoid phenotypes,and one or both of the components can be low-or high grade *** changes in the nomenclature of these neoplasms might lead to great deal of confusion,and the lack of specific clinical trials is the main reason why their management is *** review aims to clarify the definition of MiNEN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available *** would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that,due to their low incidence,will require long recruitment periods.

关键词： Mixed neuroendocrine non-neuroendocrine neoplasms Mixed adenoneuroendocrine carcinomas Mixed tumours Gastroenteropancreatic Treatment Etiology Diagnosis

Thermal Flows in the Surface Atmosphere of the Riobamba City

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Atmospheric and Climate Sciences 2014年第4期4卷 679-684页

作者： Arquímides Haro Cecilia Limaico yolanda Llosas Physics and Mathematical School Polytechnic School of Chimborazo Riobamba Ecuador Department of Automatic Control East University Santiago Cuba

This study evaluated the behavior of surface heat fluxes, in the meteorological and physical conditions of the Riobamba city (height of 2754 m regarding the sea level, geographical position 1°58'58'' Sour of latitude and 78°39'33'' West of longitude, and it is located in the Ecuadorian inter-Andean alley), these meteorological data were monitored at the ESPOCH stations of the alternative energy group during 2010-2012, and applied information processing dynamic model formulated by Van Ulden and Hostlag, which allows the determination of heat flow of sensible heat, latent heat and surface heat generated in the interaction soil-air. The measures allow us to know the average behavior of the heat flow data with variation between, 38.22, 22.15 and 155.20 W/m2 for the latent, sensible and surface heat respectively, while during the day hours significant variations in these flows that reach maximum values during the day with 139, 127 and 763 W/m2 and minimum at the night -3.9, -27.5 and -263.3 W/m2;results differ from those obtained under normal conditions at sea level.

关键词： Thermal Flows Radiation Latent Heat Surface Heat Sensible Heat

Postnatal development of fetuses with a single umbilical artery:differences between malformed and non-malformed infants

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World Journal of Pediatrics 2015年第1期11卷 61-66页

作者： Jose Vicente Arcos-Machancoses Purificación Marín-Reina Eugenia Romaguera-Salort yolanda García-Camuñas Antonio Pérez-Aytés Máximo Vento Department of Pediatrics University & Polytechnic Hospital La Fe Valencia Spain Division of Neonatology University & Polytechnic Hospital La Fe Valencia Spain Department of Obstetrics & Gynecology University & Polytechnic Hospital La Fe Valencia Spain Division of Dysmorphology & Reproductive Assessment University & Polytechnic Hospital La Fe Valencia Spain

Background:The presence of a single umbilical artery(SUA)is a fetal soft marker of congenital *** the most common related malformations,there are cardiological,nephrourological and digestive anomalies,most of which are considered to have a vascular *** is an association between increased incidence of intrauterine growth retardation and adverse perinatal indicators,but whether this association is due to related anomalies or isolated SUA(SUA)is ***:We reviewed 96 cases of iSUA and non-isolated SUA(niSUA),diagnosed in a period of two years in a referral hospital for high-risk *** on prenatal explorations,including fetal ultrasonography and karyotyping,were *** was diagnosed when no malformations were found prenatally or in postnatal ***:Sixty-six newborns(68.8%)had no other anomalies and 30(31.3%)presented with a variety of malformations including heart diseases,urophaties,digestive,nervous and musculoskeletal disorders,genetic abnormalities and complex *** and nephrourological abnormalities were found to be the most frequent association with a SUA(both in 23.8%of malformed SUA newborns).Intrauterine growth restriction was not higher in iSUA newborns than in a normal *** allowed optimal prenatal diagnosis in most ***:The prognosis of the fetus with a SUA is determined by the presence of other malformations observed by an expert *** no other findings are made,only a routine physical examination should be performed in newborns,but no other complementary examinations are required.

关键词： cardiovascular abnormalities congenital abnormalities fetal growth retardation prenatal ultrasonography single umbilical artery

Effects of high voltage electrical stimulation on the rate of pH decline,meat quality and color stability in chilled beef carcasses

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Asian Pacific Journal of Tropical Biomedicine 2013年第9期3卷 716-719页

作者： Ehsan Gharib Mombeni Manoochehr Gharib Mombeini Lucas chaves Figueiredo Luciano Soares Jacintho Siqueira Debora Testoni Dias Veterinary Medicine Shahid Chamran University of Ahvaz Provincial Animal Diseases Contro and Monitoring Khuzestan province Veterinary Organization Manager of Marfrig slaughter house plant Veterinary Inspector of Federal Inspection(SIF 3712)

Objective:To determine the effects of high voltage electrical stimulation(HVES,800 Voltage)on rapid decreases in pH values and improvements in meat ***:A total of SO beef carcasses were applied,divided into two groups,one as a control and another for *** quality was evaluated based on *** dorsi by examining pH and temperature leveb at 1,2,5,10 and 24 h,while color stability was examined seven days after ***:HVES decreased the pH values of the meat and accelerated rigor mortis(P<0.05).HVES caused differences in instrumental color values compared with the control groups across the ageing period at 4℃.Conclusion:the HVES had positive effects on meat quality and color stability,in contrast to undesirable consumer preferences.

关键词： Beef Electrical stimulation High voltage pH

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中国中小型企业保理业务的信用风险管理

中国中小型企业保理业务的信用风险管理

作者： Ingrid Tatiana chaves（英格丽）北京化工大学

学位级别：硕士

保理通常被视为一项应收账款管理政策,其中包含转包给多个信用方面的管理过程。这项管理过程的重要性主要表现在公司的业务增长很大程度上牵扯到公司的融资问题。而这点特别吸引中小企业的关注,特别是像在中国这样的国家,中小企业面临... 详细信息

保理通常被视为一项应收账款管理政策,其中包含转包给多个信用方面的管理过程。这项管理过程的重要性主要表现在公司的业务增长很大程度上牵扯到公司的融资问题。而这点特别吸引中小企业的关注,特别是像在中国这样的国家,中小企业面临的融资问题还没有得到缓解。本文面向中国地区,全面分析了“保理未能克服融资约束”的失败案例,并提出一个如何改善保理指南,并更好解决中小企业融资问题(包括信用分析管理模式)来更好地组合企业的投资、选择客户、最大化防止和避免信用风险、提高生产力,创造更多新业务流和收入。

关键词：中小型企业保理业务信用风险管理

The Farallon-Aluk ridge collision with South America:Implications for the geochemical changes of slab window magmas from fore- to back-arc

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Geoscience Frontiers 2013年第4期4卷 377-388页

作者： Eugenio Aragón Lucio Pinotti Fernando D'Eramo Antonio Castro Osvaldo Rabbia Jorge Coniglio Manuel Demartis Irene Hernando Claudia E.Cavarozzi yolanda E.Aguilera Centro de Investigaciones Geologicas(UNLP-CONICET) 1 N°644(1900) La Plata.Buenos Aires.Argentina Facultad de Ciencias Naturales y Museo Universidad Nacional de la Plata122 y 60s/n.(1900).La PlataBuenos AiresArgentina Departamento de Geologia.Universidad Nacional de Rio Cuarto.(UNRC-CONICET).Ruta 36 km 601.Rio Cuarto.Cordoba.Argentina Departamento de Geologia.Universidad de Huelva.21071 Huelva.Spain Instituto de Geologia Economica Aplicada.Universidad de Concepcion.Concepcion.Chile Departamento de Geologia.Universidad Nacional de Rio Cuarto.(UNRC-CONICET) Ruta 36 km 601.Rio Cuarto.CordobaArgentina Centro de Investigaciones Geologicas(UNLP-CONICET).1 N°644.(1900) La Plata.Buenos Aires.Argentina Facultad de Ciencias Naturales y Museo.Universidad Nacional de la Plata.122 y 60 s/n.(1900).La PlataBuenos Aires.Argentina Facultad de Ciencias Naturales y Museo.Universidad National dela Plata.122 y 60 s/n(1900)La Plata.Buenos Aires.Argentina Direccion de Aplicacion de Imagenes Satelitarias(M.O.S.P.).58 e/ 7 y 8.piso 2.1900 La Plata.Buenos Aires.Argentina

The collision of a divergent ocean ridge may evolve into two end cases： in the continuity of ocean-floor subduction, or in the detachment of the subducted plate. The northern Patagonia active plate margin has the unique situation that in Cenozoic time it has been subjected to two divergent ridge collisions, each one representing one of the end members. The Neogene Antarctica-Nazca divergent ridge collision evolved as a continuous ocean-floor subduction system, promoting a magmatic hiatus at the arc axis, the obduction of part of the ridge ocean-floor in the fore-arc, and basaltic volcanism in the back-arc. In contrast, the Paleogene Farallon-Aluk divergent ridge collision evolved into a transform margin, with the detachment and sinking of the Aluk plate and the development of a large slab window. As in the previous case, this collision promoted a magmatic hiatus at the arc axis, but the tectono-magmatic scenario changed to postorogenic synextensional volcanism that spread to the former fore-arc （basalt, andesite, rhyolite） and former back-arc （bimodal ignimbrite flare-up, basalt）. Geochemistry of this slab window synextensional volcanism shows more MORB-like basalts towards the former fore-arc, and MORB-OIB-Iike basalts towards the former back-arc. Instead, an isolated undeformable crustal block in the former back-arc, with an ＂epeirogenic＂ response to the slab window and extensional regime, was covered by OIB-type basalts after uplift. Major elements show that slab window basalts reach TiO2 values up to 3 wt%, as compared with the top value of 1.5 wt% of arc magmas. Besides, the MgO with respect to （FeOt ＋ A1203） ratio helps to distinguish slab window magma changes from the former fore-arc to the former back-arc and also with respect to the ＂epeirogenic＂ block. Higher contents of HFS elements such as Nb and Ta also help to distinguish this slab window from arc magmas and also, to distinguish slab window magma changes from the former fore-arc to the former back-arc

关键词： AndesActive ridge collisionSubduction-transform transitionSlab window volcanismSynextensional calc-alkalineBimodal volcanism

Large-scale dendrimer-based uneven nanopatterns for the study of local arginine-glycine-aspartic acid （RGD） density effects on cell adhesion

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Nano Research 2014年第3期7卷 399-409页

作者： Anna Lagunas Albert G. Castano Juan M. Artes yolanda Vida Daniel Collado Ezequiel Perez-lnestrosa Pau Gorostiza Silvia Claros Jose A. Andrades Josep Samitier Networking Biomedical Research Center in Bioengineering Biomaterials and Nanomedicine (CIBER-BBN) Spain Institute for Bioengineering of Catalonia (IBEC) Baldiri-Reixac 15-2 1 Barcelona 08028 Spain Physical Chemistry Department University of Barcelona (UB) Martii Franques 1-11 Barcelona 08028 Spain Andalusian Centre for Nanomedicine and Biotechnology (BIONAND) Severo Ochoa 35 Mdlaga 29590 Spain Organic Chemistry Department University of Mdlaga (UMA) Campus Teatinos Malaga 29071 Spain Institucio Catalana de Recerca i Estudis Avanats (ICREA) Spain Cell Biology Genetics and Physiology Department University of Malaga (UMA) Campus Teatinos Malaga 29071 Spain Electronics Department University of Barcelona (UB) Martii Franques 1-11 Barcelona 08028 Spain t Present address: Electrical and Computer Engineering Department University of California Davis 95616 Davis CA USA

Cell adhesion processes are governed by the nanoscale arrangement of the extracellular matrix （ECM）, being more affected by local rather than global concentrations of cell adhesive ligands. In many cell-based studies, grafting of dendrimers on surfaces has shown the benefits of the local increase in concentration provided by the dendritic configuration, although the lack of any reported surface characterization has limited any direct correlation between dendrimer disposition and cell response. In order to establish a proper correlation, some control over dendrimer surface deposition is desirable. Here, dendrimer nanopatterning has been employed to address arginine-glycine-aspartic acid （RGD） density effects on cell adhesion. Nanopatterned surfaces were fully characterized by atomic force microscopy （AFM）, scanning tunneling microscopy （STM） and X-ray photoelectron spectroscopy （XPS）, showing that tunable distributions of cell adhesive ligands on the surface are obtained as a function of the initial dendrimer bulk concentration. Cell experiments showed a clear correlation with dendrimer surface layout： Substrates presenting regions of high local ligand density resulted in a higher percentage of adhered cells and a higher degree of maturation of focal adhesions （FAs）. Therefore, dendrimer nano- patterning is presented as a suitable and controlled approach to address the effect of local ligand density on cell response. Moreover, due to the easy modification of dendrimer peripheral groups, dendrimer nanopatterning can be further extended to other ECM ligands having density effects on cells.

关键词： dendrimer arginine-glycine-asparticacid atomic force microscopy scanning tunnelingmicroscopy cell adhesion focal adhesions