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Parameters Affecting the Fuel Cell Reactions on Platinum Bimetallic Nanostructures

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Electrochemical Energy Reviews 2023年第1期6卷 830-853页

作者： Nicolas alonso‑Vante IC2MP UMR-CNRS 7285University of Poitiers4 rue Michel Brunet86072 PoitiersFrance

In this paper the electrochemical properties of some platinum-based nanoalloys are *** revision is centered on electrocatalytic materials generated via the carbonyl chemical route(CCR).In considering the effects of segregation in these bimetals,the reaction of the hydrogen oxidation(HOR)and oxygen reduction(ORR)in the alkaline medium was *** reaction kinetics of these electrochemical processes in the alkaline electrolyte is still a *** the design of high-performance platinum-based electrocatalysts,it is of importance to know that the kinetics of HOR and ORR also depends on the Pt *** electrochemical analysis,based on the study of Pt nanoalloyed surfaces with different Pt-adsorbate interactions,was taken into account.A clear trend in the HOR as well as the ORR activity,in the alkaline electrolyte,was established,revealing that the activity changes in the order PtSn/C

关键词： Electrocatalysts HOR HER ORR Pt-based materials Bimetallic Carbon domains

Flow near a model spur dike with a fixed scoured bed

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International Journal of Sediment Research 2013年第3期28卷 349-357页

作者： Roger KUHNLE Carlos alonso National Sedimentation Laboratory U.S.Department of AgricultureAgricultural Research Service

Three-dimensional flow velocities were measured using an acoustic Doppler velocimeter at a closely spaced grid over a fixed scoured bed with a submerged spur ***-dimensional flow velocities were measured at 3,484 positions around the trapezoidal shaped submerged model spur *** velocity distributions and detailed near field flow structures were revealed by the *** differences were revealed between flow over fixed flat and scoured *** lateral flows were the dominant cause of the observed local *** stresses were higher for the scoured bed than in the flat bed *** rates of scour as the scour hole developed were attributed to increases in critical shear stress in the scour holes caused by the increase in the length and magnitude of adverse slopes associated with the two main scour holes.

关键词： Submerged spur dike 3-dimensional flow Velocity measurements Free surface flow Hydraulic structure

Bigger or long-winged male common crossbills exhibit redder carotenoid-based plumage coloration

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Current Zoology 2023年第2期69卷 165-172页

作者： Blanca Fernandez-Eslava Daniel alonso David Galicia Juan Arizaga Carlos alonso-Alvarez Biologia Ambiental Universidad de NavarraFacultad de CienciasC/Irunlarrea1 Pamplona31008 NavarraSpain Ornitologia Sociedad de Ciencias de AranzadiZorroagagaina 1120014 DonostiaSan SebastianSpain Ecologia Evolutiva Museo Nacional de Ciencias Naturales(CSiC)Edificio Pinar 2528006 MadridSpain

Carotenoid-based ornaments are often considered reliable(honest)individual condition signals because their expression implies physiological costs unaffordable for low-quality animals(handicap signals).Recently,it has been suggested that efficient cell respiration is mandatory for producing red ketocarotenoids from dietary yellow *** implies that red colorations should be entirely unfalsifiable and independent of expression costs(index signals).In a precedent study,male common crossbills,Loxia curvirostra,showing a red plumage reported higher apparent survival than those showing yellowish-orange *** plumage redness in this species is due to ketocarotenoid accumulation in ***,we correlated the male plumage redness(a 4-level visual score:yellow,patchy,orange,and red)and the body morphology in more than 1,ooo adult crossbills captured in 3 Iberian localities to infer the mechanisms responsible for color evolution.A principal component analysis summarized morphometry of 10 variables(beak,wing,tarsus length,etc.).The overall body size(PC1)and the length of flight feathers regarding body size(Pc3)showed significant positive relationships with plumage *** redness was barely correlated with bill shape measures,suggesting no constraint in acquiring carotenoids from pine ***,large body sizes or proportionally long flying feathers could help carotenoid acquisition via social competition or increased foraging *** longer flight feathers might also be associated with a specific cell respiration profile that would simultaneously favor flying capacities and enzymatic transformations needed for ketocarotenoid *** a phenotypic profile would agree with the hypothesis of ketocarotenoid-based colors acting as individual quality index signals.

关键词： avian carotenoids color and biometrics Loxia genus Mediterranean crossbills resource allocation trade-offs shared pathway hypothesis

Back-to-Front Ordering of Triangles in Digital Terrain Models over Regular Grids

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Journal of Computer Science & Technology 2018年第6期33卷 1192-1203页

作者： Jesús alonso Robert Joan-Arinyo Informatics in Engineering Group Technical University of Catalonia 08028 Barcelona Catalonia Center for Biomedical Engineering Research Sant Joan de Ddu Research Institute 08028 Barcelona Catalonia Visualization Interaction and Virtual Reality Group Technical University of Catalonia 08028 Barcelona Catalonia

Visiting triangles that conform a digital terrain model is a core operation in a number of fields like animationand video games or generating profiles, cross-sections, and contours in civil engineering. Perfornfing the visit in an efficientmanner is an issue specially when the output of the traversal depends in some way on additional parameters or informationchanging over time, for example, a moving point of view. In this work we report a set of rules that, given a digital terrainmodel defined over a regular grid and an arbitrary point of view outside the terrain, define a total back-to-front order in theset of digital terrain model triangles with respect to the point. The set of rules is minimal, complete and correct. To assesshow the rules perform, we have implemented a CPU-based algorithm for realistically rendering height fields defined overregular grids. The algorithm does not make use of the z-buffer or shaders featured by our graphics card. We show how ouralgorithm is implemented and show visual results obtained from synthetic and real data. We further discuss the algorithmperformance with respect to two algorithms： a naive algorithm that visits triangles according to grid indices and does notsolve the hidden line problem, and the z-buffer provided by the graphics card featured by our computer. Our algorithmallows real-time interaction when the point of view arbitrarily moves in 3D space and we show that its performance is asgood as that of the z-buffer graphics card.

关键词： back-to-front ordering digital terrain model elevation terrain model triangle strip, visibility

Current focus of stem cell application in retinal repair

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World Journal of Stem Cells 2015年第3期7卷 641-648页

作者： Maria L alonso-alonso Girish Kumar Srivastava Instituto Universitario de Oftalmobiologia Aplicada (IOBA) Universidad de Valladolid 47011 Valladolid Spain Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y Leon 47011 Valladolid Spain

The relevance of retinal diseases, both in society's economy and in the quality of people's life who suffer with them, has made stem cell therapy an interesting topic forresearch. Embryonic stem cells(ESCs), induced pluripotent stem cells(i PSCs) and adipose derived mesenchymal stem cells(ADMSCs) are the focus in current endeavors as a source of different retinal cells, such as photoreceptors and retinal pigment epithelial cells. The aim is to apply them for cell replacement as an option for treating retinal diseases which so far are untreatable in their advanced stage. ESCs, despite the great potential for differentiation, have the dangerous risk of teratoma formation as well as ethical issues, which must be resolved before starting a clinical trial. i PSCs, like ESCs, are able to differentiate in to several types of retinal cells. However, the process to get them for personalized cell therapy has a high cost in terms of time and money. Researchers are working to resolve this since i PSCs seem to be a realistic option for treating retinal diseases. ADMSCs have the advantage that the procedures to obtain them are easier. Despite advancements in stem cell application, there are still several challenges that need to be overcome before transferring the research results to clinical application. This paper reviews recent research achievements of the applications of these three types of stem cells as well as clinical trials currently based on them.

关键词： Retina Adipose derived mesenchymal stemcells Embryonic stem cells Induced pluripotent stemcells Cell therapy

How Software Engineering Transforms Organizations: An Open and Qualitative Study on the Organizational Objectives and Motivations in Agile Transformations

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Computers, Materials & Continua 2024年第11期81卷 2935-2966页

作者： alonso Alvarez Borja Bordel Sánchez Department of Informatic Systems Universidad Politécnica de MadridMadrid28031Spain

Agile Transformations are challenging processes for organizations that look to extend the benefits of Agile philosophy and methods beyond software *** the impact of these transformations on orga-nizations,they have not been extensively studied in *** conducted a study grounded in workshops and interviews with 99 participants from 30 organizations,including organizations undergoing transformations(“final organizations”)and companies supporting these processes(“consultants”).The study aims to understand the motivations,objectives,and factors driving and challenging these *** 700 responses were collected to the question and categorized into 32 *** findings show that organizations primarily aim to achieve customer centricity and adaptability,both with 8%of the *** primary important objectives,with above 4%of mentions,include alignment of goals,lean delivery,sustainable processes,and a flatter,more team-based organizational *** also detect discrepancies in perspectives between the objectives identified by the two kinds of organizations and the existing agile literature and *** misalignment highlights the need for practitioners to understand with the practical realities the organizations face.

关键词： Business agility agile agile transformations agile enterprises adaptive organizations adaptability agile software development software engineering computer engineering

Global Trends of Usage of Chlorophyll Fluorescence and Projections for the Next Decade

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Plant Phenomics 2020年第1期2卷 409-418页

作者： alonso Zavafer Leen Labeeuw Cristian Mancilla Research School of Biology The Australian National UniversityCanberraACTAustralia University of Technology Sydney Climate Change ClusterFaculty of ScienceSydneyNSW 2007Australia Independent Researcher La FloridaChile

Chlorophyll fluorescence is the most widely used set of techniques to probe photosynthesis and plant *** great versatility has given rise to different routine methods to study plants and *** three main technical platforms are pulse amplitude modulation(PAM),fast rise of chlorophyll fluorescence,and fast repetition ***-induced fluorescence(SIF)has also gained interest in the last few *** have compared their advantages and their underlying theory,with many arguments advanced as to which method is the most accurate and *** date,no data has assessed the exact magnitude of popularity and influence for each *** this work,we have taken the bibliometrics of the past decade for each of the four platforms,have evaluated the public scientific opinion toward each method,and possibly identified a geographical *** used various metrics to assess influence and popularity for the four routine platforms compared in this study and found that,overall,PAM currently has the highest values,although the more recent SIF has increased in popularity rapidly during the last *** indicates that PAM is currently one of the fundamental tools in chlorophyll fluorescence.

关键词： algae routine Fluorescence

Alternative approaches for estimating missing climate data:application to monthly precipitation records in South- Central Chile

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Forest Ecosystems 2018年第4期5卷 390-399页

作者： alonso Barrios Guillermo Trincado Rene Garreaud Escuela de Graduados Facultad de Ctencias Forestales y Recursos Naturales Universidad Austral de ChileBox 567ValdiviaChile Departamento de Ciencias Forestales Facuitad de Ingenieria ForestalUnlversidad del Tolima Box 6299 Ibague Colombia Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austraide ChileBox 567 ValdiviaChile Departamento de Geofistca Facultad de Ciencias Fisicas y MatematicasUniversidad de ChileSantiagoChile

Background: Over the last decades interest has grown on how climate change impacts forest resources. However,one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting(IDW), a modification of IDW that includes elevation differences between target and neighboring stations(IDW_m), correlation coefficient weighting(CCW), multiple linear regression(MLR) and artificial neural networks(ANN).Methods: A complete series of monthly precipitation records(1995-2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of25 km(3 stations) and 50 km(9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data(RSR), the percent bias(PBIAS), and the NashSutcliffe efficiency(NSE). For testing the main and interactive effects of the radius of influence and estimation approaches,a two-level factorial design considering the target station as the blocking factor was ***: ANN and MLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDW_m. Inclusion of elevation differences into IDW significantly improved IDW_m estimates. In terms of precision, similar estimates were obtained when applying ANN, MLR or IDW_m, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex ***: It is concluded that approaches based on ANN

关键词： Climatological data Cross-validation Artificial neural networks Multiple linear regression

Stem cell-based approaches: Possible route to hearing restoration?

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World Journal of Stem Cells 2020年第6期12卷 422-437页

作者： María Beatriz Durán-alonso Institute of Biology and Molecular Genetics University of ValladolidValladolid 47003Spain

Disabling hearing loss is the most common sensorineural disability *** affects around 466 million people and its incidence is expected to rise to around 900 million people by 2050,according to World Health Organization *** cases of hearing impairment are due to the degeneration of hair cells(HCs)in the cochlea,mechano-receptors that transduce incoming sound information into electrical signals that are sent to the *** to these cells is mainly caused by exposure to aminoglycoside antibiotics and to some anti-cancer drugs such as cisplatin,loud sounds,age,infections and genetic *** deficits may also result from damage to the spiral ganglion neurons that innervate cochlear *** from what is observed in avian and nonmammalian species,there is no regeneration of missing sensory cell types in the adult mammalian cochlea,what makes hearing loss an irreversible *** review summarizes the research that has been conducted with the aim of developing cell-based strategies that lead to sensory cell replacement in the adult cochlea and,ultimately,to hearing *** main lines of research are discussed,one directed toward the transplantation of exogenous replacement cells into the damaged tissue,and another that aims at reactivating the regenerative potential of putative progenitor cells in the adult inner *** from some of the studies that have been conducted are presented and the advantages and drawbacks of the various approaches discussed.

关键词： Hearing loss Cochlear hair cells Spiral ganglion neurons Cell regeneration Adult stem cells Cell transplantation