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Fast preparation route to high-performances textured Sr-doped Ca_3Co_4O_9 thermoelectric materials through precursor powder modification

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Science China Materials 2019年第3期62卷 399-406页

作者： miguel Angel Torres Gustavo Garcia Idoia Urrutibeascoa Maria Antonieta Madre juan Carlos Diez Andres Sotelo ICMA (CSIC-Universidad de Zaragoza) Centro Stirling S. Coop. Mondragon Unibertsitatea

This work presents a short and very efficient method to produce high performance textured Ca_3Co_4O_9 thermoelectric materials through initial powders modification. Microstructure has shown good grain orientation, and low porosity while slightly lower grain sizes were obtained in samples prepared from attrition milled powders. All samples show the high density of around 96% of the theoretical *** similar characteristics are reflected in, approximately,the same electrical resistivity and Seebeck coefficient values for both types of samples. However, in spite of similar power factor(PF) at low temperatures, it is slightly higher at high temperature for the attrition milled samples. On the other hand, the processing time reduction(from 38 to 2 h) when using attrition milled precursors, leads to lower mechanical properties in these samples. All these data clearly point out to the similar characteristics of both kinds of samples, with a drastic processing time decrease when using attrition milled precursors, which is of the main economic importance when considering their industrial production.

关键词： ceramics oxides hot-pressing electrical properties power factor

A facile one-pot hydrothermal synthesis as an efficient method to modulate the potassium content of cryptomelane and its effects on the redox and catalytic properties

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Chinese Journal of Catalysis 2019年第6期40卷 940-952页

作者： Huiyan Pan Xiaowei Chen Oihane Sanz miguel A.Cauquia Jose M.Rodriguez-Izquierdoa juan J.Delgado Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica Facultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain Applied Chemistry Department University of Basque Country(UPV-EHU)Apdo.1072San Sebastian20080Spain

Cryptomelane has been widely applied as catalyst in oxidation reactions due to its excellent redox properties and low ***,a novel one-pot hydrothermal synthesis using a potassium permanganate aqueous solution as precursor and ethanol as reducing agent has successfully been developed to obtain cryptomelane *** synthetic route makes it possible to control the amount of potassium incorporated into the structure of the cryptomelane by selecting the appropriate synthesis temperature and ethanol initial *** advantage of this approach,the effect of potassium concentration on the structural stability and reducibility of the cryptomelane,which are poorly discussed in the literature,has been *** have observed that samples with low content of potassium(~11%)show high conversions of CO to CO2 especially at low *** lower activity of the samples with high K contents(~16%)can be ascribed to the beneficial effect of K on the structural stability of cryptomelane in detriment of labile oxygen on cryptomelane surface.

关键词： Cryptomelane Pyrolusite Catalytic CO oxidation Hydrothermal synthesis Potassium content

An experimental study on the conversion between IFPUG and UCP functional size measurement units

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第3期15卷 161-173页

作者： juan J.CUADRADO-GALLEGO Alain ABRAN Pablo RODRíGUEZ-SORIA miguel A.LARA Ecole de Technologie Supérieure-ETS 1100 Notre-Dame Ouest Computer Science Department University of Alcala

The use of functional size measurement(FSM) methods in software development organizations is growing during the years. Also, object oriented(OO) techniques have become quite a standard to design the software and, in particular, Use Cases is one of the most used techniques to specify functional requirements. Main FSM methods do not include specific rules to measure the software functionality from its Use Cases analysis. To deal with this issue some other methods like Kramer's functional measurement method have been developed. Therefore, one of the main issues for those organizations willing to use OO functional measurement method in order to facilitate the use cases count procedure is how to convert their portfolio functional size from the previously adopted FSM method towards the new method. The objective of this research is to find a statistical relationship for converting the software functional size units measured by the International Function Point Users Group(IFPUG) function point analysis(FPA) method into Kramer-Smith's use cases points(UCP) method and vice versa. Methodologies for a correct data gathering are proposed and results obtained are analyzed to draw the linear and non-linear equations for this correlation. Finally, a conversion factor and corresponding conversion intervals are given to establish the statistical relationship.

关键词： Software engineering Requirements analysis Functional size measurement Use cases analysis Object oriented Function point analysis Use cases points

Does an association exist between chronic pancreatitis and liver cirrhosis in alcoholic subjects?

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World Journal of Gastroenterology 2008年第40期14卷 6171-6179页

作者： Luis Aparisi Luis Sabater juan Del-Olmo juan Sastre miguel-Angel Serra Ricardo Campello Daniel Bautista Abdalla Wassel José-Manuel Rodrigo Liver Unit Universitary Clinic Hospital Department of Surgery Universitary Clinic Hospital Department of Physiology University of Valencia Unit of Psiquiatry Servicio Valenciano de SaludValencia 46010Spain Department of Preventive Medicine Hospital Dr.Peset

AIM: To study the possible association between chronic pancreatitis (CP) and liver cirrhosis (LC) of alcoholic etiology,after excluding any other ***: One hundred and forty consecutive alcoholic patients were subdivided into three groups: CP (n = 53),LC (n = 57),and asymptomatic alcoholic (n = 30).Clinical,biochemical and morphological characteristics,Child-Pugh index,indocyanine green test,and fecal pancreatic elastase-1 test were ***: In patients with cirrhosis,major clinical manifestations of CP such as pancreatic pain and steatorrhea,as well as imaging alterations of CP such as calcifications,duct dilation and pseudocysts were absent; insulin-dependent diabetes was present in 5.3% of cases,and elastase-1 test was altered in only 7%,and severely altered in *** patients with CP,clinical characteristics of cirrhosis such as ascites,encephalopathy and gastrointestinal hemorrhage were present in one case,Child-Pugh grade > A in 5.7%,and altered indocyanine green test in 1.9% *** asymptomatic alcoholism,there was only a non-coincident alteration of elastase-1 test and indocyanine test in 14.8% and 10%,respectively,but other characteristics of cirrhosis or CP were *** inverse correlation (r = -0.746) between elastase-1 test and indocyanine test was found in alcoholic ***: There is a scarce coincidence in clinical and morphological alterations among patients with CP or LC of alcoholic etiology,but an inverse correlation between pancreatic and liver function *** findings support that these alcoholic diseases evolve in a different manner and have different etiopathogenesis.

关键词： Alcoholic chronic pancreatitis Alcoholicliver cirrhosis Alcoholism Pancreatic function Hepaticfunction

Performance of statistical and machine learning-based methods for predicting biogeographical patterns of fungal productivity in forest ecosystems

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Forest Ecosystems 2021年第2期8卷 278-291页

作者： Albert Morera juan Martínez de Aragón José Antonio Bonet Jingjing Liang Sergio de-miguel Department of Crop and Forest Sciences University of LleidaAv.Alcalde Rovira Roure 191E-25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Center Av.Rovira Roure 19125198 LleidaSpain Forest Science and Technology Centre of Catalonia Ctra.Sant Llorençde Morunys km 225280 SolsonaSpain Forest Advanced Computing and Artificial Intelligence Laboratory Department of Forestry and Natural ResourcesPurdue UniversityWest LafayetteIN 47907USA

Background:The prediction of biogeographical patterns from a large number of driving factors with complex interactions,correlations and non-linear dependences require advanced analytical methods and modeling *** study compares different statistical and machine learning-based models for predicting fungal productivity biogeographical patterns as a case study for the thorough assessment of the performance of alternative modeling approaches to provide accurate and ecologically-consistent ***:We evaluated and compared the performance of two statistical modeling techniques,namely,generalized linear mixed models and geographically weighted regression,and four techniques based on different machine learning algorithms,namely,random forest,extreme gradient boosting,support vector machine and artificial neural network to predict fungal *** evaluation was conducted using a systematic methodology combining random,spatial and environmental blocking together with the assessment of the ecological consistency of spatially-explicit model predictions according to scientific ***:Fungal productivity predictions were sensitive to the modeling approach and the number of predictors ***,the importance assigned to different predictors varied between machine learning modeling *** tree-based models increased prediction accuracy by more than 10%compared to other machine learning approaches,and by more than 20%compared to statistical models,and resulted in higher ecological consistence of the predicted biogeographical patterns of fungal ***:Decision tree-based models were the best approach for prediction both in sampling-like environments as well as in extrapolation beyond the spatial and climatic range of the modeling *** this study,we show that proper variable selection is crucial to create robust models for extrapolation in biophysically differentiated *** allows for reducing the dime

关键词： Modeling Regression Biogeography Climate Forest Fungi Mushrooms

Plasmodium vivax cerebral malaria complicated with venous sinus thrombosis in Colombia

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Asian Pacific Journal of Tropical Medicine 2013年第5期6卷 413-415页

作者： miguel A Pinzon juan C Pineda Fernando Rosso Masaru Shinchi Fabio Bonilla-Abadia Department of Infectious Diseases Hospital San Vicente de PaulMedellinColombia Department of Internal Medicine Fundacion Clinica Valle del LiliICESI UniversityCaliColombia Department of Infectious Diseases Fundacion Clinica Valle del LiliCaliColombia Department of Neurology Fundacion Clinica Valle del LiliCuliColombia Department of Rheumatology Fundacion Clinica Valle del LiliICESI UniversityCaliColombia

Complicated malaria is usually due to Plasmodium ***,Plasmodium vivax is infrequently related with life-threatening *** cases have been reported of severe Plasmodium vivax infection,and most of them from Southeast Asia and *** report the first case of cerebral malaria due to Plasmodium vivax in Latin America,complicated with sagittal sinus thrombosis and confirmed by a molecular method.

关键词： Cerebral malaria Vivax malaria Plasmodium vivax Intracranial sinus thrombosis

Planetary Gear Profile Modification Design Based on Load Sharing Modelling

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 810-820页

作者： IGLESIAS miguel FERNáNDEZ DEL RINCóN Alfonso DE-juan Ana Magdalena GARCIA Pablo DIEZ Alberto VIADERO Fernando Mechanical Engineering Research Group University of Cantabria

In order to satisfy the increasing demand on high performance planetary transmissions, an important line of research is focused on the understanding of some of the underlying phenomena involved in this mechanical system. Through the development of models capable of reproduce the system behavior, research in this area contributes to improve gear transmission insight, helping developing better maintenance practices and more efficient design processes. A planetary gear model used for the design of profile modifications ratio based on the levelling of the load sharing ratio is presented. The gear profile geometry definition, following a vectorial approach that mimics the real cutting process of gears, is thoroughly described. Teeth undercutting and hypotrochoid definition are implicitly considered, and a procedure for the incorporation of a rounding arc at the tooth tip in order to deal with corner contacts is described. A procedure for the modeling of profile deviations is presented, which can be used for the introduction of both manufacturing errors and designed profile modifications. An easy and flexible implementation of the profile deviation within the planetary model is accomplished based on the geometric overlapping. The contact force calculation and dynamic implementation used in the model are also introduced, and parameters from a real transmission for agricultural applications are presented for the application example. A set of reliefs is designed based on the levelling of the load sharing ratio for the example transmission, and finally some other important dynamic factors of the transmission are analyzed to assess the changes in the dynamic behavior with respect to the non-modified case. Thus, the main innovative aspect of the proposed planetary transmission model is the capacity of providing a simulated load sharing ratio which serves as design variable for the calculation of the tooth profile modifications.

关键词： transmission planetary gear load sharing relief profile modification

Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, Ecuador 1990-2008

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Journal of Forestry Research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-Bedoya juan R.Molina José E.Macedo-Pezzopane miguel A.Herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon Region （EAR）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the

关键词： Ecuadorian Amazon systematic transitions fragmentation natural regeneration

Note on X(3872) production at hadron colliders and its molecular structure

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Chinese Physics C 2017年第12期41卷 1-3页

作者： miguel Albaladejo 郭奉坤 Christoph Hanhart Ulf-G.Mei?ner juan Nieves Andreas Nogga 杨智 Departamento de Física Universidad de Murcia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron Physics Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universitt Bonn Instituto de Física Corpuscular (IFIC) Centro Mixto CSIC-Universidad de ValenciaInstitutos de Investigación de Paterna Institute of Modern Physics Chinese Academy of Sciences

The production of the X（3872） as a hadronic molecule in hadron colliders is clarified. We show that the conclusion of Bignamini et al., Phys. Rev. Lett. 103（2009） 162001, that the production of the X（3872） at high pT implies a non-molecular structure, does not hold. In particular, using the well understood properties of the deuteron wave function as an example, we identify the relevant scales in the production process.

关键词： X(3872) hadronic molecules exotic hadrons