bluuebunny/crossref_metadata_2025 huggingface dataset:
From runoff to rainfall: inverse rainfall–runoff modelling in a high temporal resolution
Authors: Herrnegger M. , Nachtnebel H. P. , Schulz K.
Published: December 2014

Abstract. This paper presents a novel technique to calculate mean areal rainfall in a high temporal resolution of 60 min on the basis of an inverse conceptual rainfall–runoff model and runoff observations. Rainfall exhibits a large spatio-temporal variability, especially in complex alpine terrain. Additionally, the density of the monitoring network in mountainous regions is low and measurements are subjected to major errors, which lead to significant uncertainties in areal rainfall estimates. The most reliable hydrological information available refers to runoff, which in the presented work is used as input for a rainfall–runoff model. Thereby a conceptual, HBV-type model is embedded in an iteration algorithm. For every time step a rainfall value is determined, which results in a simulated runoff value that corresponds to the observation. To verify the existence, uniqueness and stability of the inverse rainfall, numerical experiments with synthetic hydrographs as inputs into the inverse model are carried out successfully. The application of the inverse model with runoff observations as driving input is performed for the Krems catchment (38.4 km2), situated in the northern Austrian Alpine foothills. Compared to station observations in the proximity of the catchment, the inverse rainfall sums and time series have a similar goodness of fit, as the independent INCA rainfall analysis of Austrian Central Institute for Meteorology and Geodynamics (ZAMG). Compared to observations, the inverse rainfall estimates show larger rainfall intensities. Numerical experiments show, that cold state conditions in the inverse model do not influence the inverse rainfall estimates, when considering an adequate spin-up time. The application of the inverse model is a feasible approach to obtain improved estimates of mean areal rainfall. These can be used to enhance interpolated rainfall fields, e.g. for the estimation of rainfall correction factors, the parameterisation of elevation dependency or the application in real-time flood forecasting systems.
Influence of weak layer heterogeneity and slab properties on slab tensile failure propensity and avalanche release area
Authors: Gaume J. , Chambon G. , Eckert N. , Naaim M. , Schweizer J.
Published: December 2014

Abstract. Dry-snow slab avalanches are generally caused by a sequence of fracture processes including failure initiation in a weak snow layer underlying a cohesive slab followed by crack propagation within the weak layer (WL) and tensile fracture through the slab. During past decades, theoretical and experimental work has gradually improved our knowledge of the fracture process in snow. However, our limited understanding of crack propagation and fracture arrest propensity prevents the evaluation of avalanche release sizes and thus impedes hazard assessment. To address this issue, slab tensile failure propensity is examined using a mechanically-based statistical model of the slab–WL system based on the finite element method. This model accounts for WL heterogeneity, stress redistribution by elasticity of the slab and the slab possible tensile failure. Two types of avalanche release are distinguished in the simulations: (1) full-slope release if the heterogeneity is not sufficient to stop crack propagation and to trigger a tensile failure within the slab, (2) partial-slope release if fracture arrest and slab tensile failure occurs due to the WL heterogeneity. The probability of these two release types is presented as a function of the characteristics of WL heterogeneity and of the slab. One of the main outcomes is that, for realistic values of the parameters, the tensile failure propensity is mainly influenced by slab properties. Hard and thick snow slabs are more prone to wide-scale crack propagation and thus lead to larger avalanches (full-slope release). In this case, the avalanche size is mainly influenced by topographical and morphological features such as rocks, trees, slope curvature and the spatial variability of the snow depth as it is often claimed in the literature.
Images of innovation in discourses of free and open source software
Authors: Dafermos George , Van Eeten Michel J.G.
Published: December 2014

In this study, we examine the relationship between innovation and free/open source software (FOSS) based on the views of contributors to FOSS projects, using Q methodology as a method of discourse analysis to make visible the positions held by FOSS contributors and identify the discourses encountered in the FOSS community. In specific, our analysis reveals four discourses: four ways of expressing oneself used by FOSS contributors, which, aside from certain commonalities, postulate fundamentally different conceptions of innovation. Whereas the dispersion of FOSS contributors’ subjectivity across four different discourses is indicative of the diversity and heterogeneity of the FOSS community, their commonalities, however, demarcate a common ground that all discourses share: points of agreement include the negative effect of patents on innovation, the predominant role of end users over manufacturers in the innovation process and the embrace of FOSS licenses as a key enabler of innovation. In the conclusion, we outline some implications for innovation management and policy.
The functions of buzzwords: A comparison of ‘Web 2.0’ and ‘telematics’
Authors: Mjøs Ole J. , Moe Hallvard , Sundet Vilde Schanke
Published: December 2014

It is a key task for media research to uncover the assumptions underpinning fashion terms like buzzwords, and to show their functions in business, political debate and social life. In this article, we ask which purposes media buzzwords serve, and for whom. We also question the presumed newness of buzzwords. By critically addressing two corresponding terms — ‘Web 2.0’ and ‘telematics’ — we argue that a media buzzword serves three important functions: it simplifies a complex field, promotes a phenomenon as something new, and legitimates strategies and actions. Thus, a media buzzword can be used rhetorically to define a discursive frame for new media developments. Further, we argue, even though media buzzwords bring forward a promise of something new, the use of such buzzwords is not new.
Disconnect: A case study of short-term voluntary mobile phone non-use
Authors: Lee Sun Kyong , Katz James E.
Published: December 2014

A group of young adults were observed and interviewed as they spent a weekend without access to the mobile phone and Internet. Thirty-seven students participated in a program, entitled “unplugged weekend.” How they experienced the social interactions and flow of time without the usual interruption by mobile communication was the main point of examination. Contrary to our expectations, the 48-hour period of disconnection was judged to be a unique, entertaining, and satisfactory experience for most participants. Using humor, establishing common grounds, and uses of the body were three main characteristics of co-present social interactions observed during the trip. There were “dual” perceptions of time flow: Some reported that time slowed down whereas others reported that time flew rather quickly throughout the weekend. Overall, many participants rediscovered the value of co-present embodied interactions by sharing various activities while giving undivided attention to one another.
HIGHLY IMPERMEABLE NANOCOMPOSITES OF BROMINATED BUTYL RUBBER WITH MODIFIED MONTMORILLONITE CLAY
Authors: Kumar Arun , Modi Satyam , Panwar Artee , Schmidt Daniel , Barry Carol M. F. , Mead Joey L.
Published: December 2014

Incorporation of nanoclays in vulcanized rubber can enhance the barrier and mechanical properties, with the aid of intercalation, exfoliation, or both. Achieving a high degree of dispersion such as intercalation and exfoliation is critical for obtaining optimal properties. In this work, a stepwise approach was developed to disperse the natural montmorillonite (MMT) clay modified with a quaternary ammonium salt in brominated butyl rubber (BIIR). The solvent intercalation method followed by mechanical shear was used to effectively intercalate/exfoliate the MMT bundles. Special consideration was given to effectively remove the solvent from the solvent intercalated master batch. The nanocomposites fabricated using this technique showed a high degree of intercalation and exfoliation along with improved barrier, dynamic mechanical, and mechanical properties. This improvement in properties offers an opportunity for this material to be used in high-end applications requiring improved mechanical as well as barrier properties; an example is a thinner tire inner liner with reduced hysteresis, lower running temperatures, and reduced fuel consumption.
Conocimientos, actitudes y práctica del uso y manejo de Plaguicidas por pequeños productores de los Municipios de Chinandega, en el período Septiembre-Octubre del 2006
Authors: López Narváez Lilliam , López Bonilla Indiana , Carrero Palacios Russel Auxiliadora , Cruz Blandón Carmen Marina
Published: December 2014

Debido al uso irracional de plaguicidas por los agricultores para el control de las plagas, se realizó un estudio descriptivo sobre “Conocimientos, Actitudes y Prácticas del uso y manejo de plaguicidas” en pequeños productores en municipios del Departamento de Chinandega. Se encuestaron 190 agricultores; la recolección de datos, se realizó aplicando un cuestionario. La mayoría de los encuestados, fueron mayores de 45 años, con estudios primarios, trabajan por cuenta propia; con más de 20 años de experiencia y refieren han recibido muy pocas capacitaciones. Los plaguicidas más conocidos son Gramoxone, 2,4-D, y Lorsban; el 78% conoce los síntomas de una intoxicación, el 66% se informa de la peligrosidad por medio de las instrucciones de la etiqueta, sin embargo, el 91% desconoce el significado de los pictogramas. La falta de dinero, es la principal razón por la que no usan el equipo de protección, sin embargo, reconocen situaciones de peligro para intoxicarse. La vestimenta que utilizan cuando aplican plaguicida, es camisa manga larga, pantalón largo, gorra y botas de hule. Se identifica la necesidad de ampliar la cobertura de capacitaciones a los agricultores, e incluir contenidos de promoción de alternativas al uso de plaguicida.DOI: http://dx.doi.org/10.5377/universitas.v2i1.1644
Estado nutricional en niños del tercer nivel de los preescolares: El Jardín de Infancia Rubén Darío y Escuela Rubén Darío de la ciudad de León
Authors: Benavides Reyes Martha Lidia , Bermúdez Vélasquez Sayra Yubelka , Berrios Salinas Franklin Francisco , Bert Spittler Philip John , Delgado Rodríguez Patricia Mercedes , Castellón Cisneros Efrén Ali
Published: December 2014

Un buen estado nutricional ayuda al buen desarrollo físico e intelectual y contribuye a asegurar una vida larga y saludable. Identificando el estado nutricional de una comunidad y sus factores permite evaluar los programas de salud para poder hacer cambios necesarios. El propósito de este trabajo es evaluar el estado nutricional y los factores socioeconómicos niños del tercer nivel de los preescolares el Jardín de Infancia Rubén Darío y Escuela Rubén Darío de la ciudad de León. Se realizó medidas antropométricas en los niños de la población antemencionada y se determinó su clasificación nutricional utilizando puntaje Z. También se administró una encuesta a los padres de los niños para recopilar datos socioeconómicos. Utilizando los parámetros de P/T se encontró que 16.8% de los niños tenían una desnutrición leve, 5% una desnutrición moderada y 1 niño presentaba desnutrición severa. Se encontró 55.4% presentaban una nutrición normal, 13% obesidad y 8% de los niños en sobrepeso. Los niños de la Escuela Rubén Darío eran más propensos a presentar desnutrición mientras que los niños del Jardín de Infancia eran más propensos a presentar sobrepeso u obesidad. Entre los factores socioeconómicos más influyentes se encontró el ingreso económico de la familia, nivel educativo de los padres y el hábito de comer entre comidas.DOI: http://dx.doi.org/10.5377/universitas.v2i2.1647
Tovaria pendula Ruiz & Pav., (Tovariaceae), nueva especie, género y familia para Nicaragua
Authors: Paguaga R Dania L
Published: December 2014

Se describe e ilustra la especie Tovaria pendula Ruiz & Pav., que representa un nuevo registro para la flora de Nicaragua. La familia Tovariaceae, está representada por el género Tovaria, el cual es de amplia distribución en América Tropical, pero en las Antillas se conoce únicamente de Jamaica. En Nicaragua fue colectada por primera vez en la montaña Cerro de Jesús, municipio de Jalapa, departamento de Nueva Segovia, a una altitud de 1400 a 1500 m, en las coordenadas 13°58´37´´ N, 86°10´29´´W, durante una evaluación florística rápida.DOI: http://dx.doi.org/10.5377/universitas.v3i1.1657
Validación y verificación de métodos de ensayos. Un dilema en los laboratorios de ensayos y en las auditorías de la acreditación
Authors: Delgado Gustavo
Published: December 2014

El presente artículo tiene como objetivo fundamental establecer en forma clara y sencilla la diferencia entre validación y verificación de un método de ensayo. Se presenta una breve discusión de la selección y validación de los métodos de ensayos establecidos en la norma ISO/IEC 17025:2005. Se describe el proceso de normalización de un método. Se describen brevemente los parámetros de la validación como indicadores característicos del desempeño del método, brindando algunas breves orientaciones para su aplicación. Se presentan algunos contenidos de métodos normalizados, indicando las especificaciones a partir de los datos de validación. Y por último se describe el proceso de verificación y su diferencia con la validación, haciendo énfasis en la confirmación de las especificaciones del método. DOI: http://dx.doi.org/10.5377/universitas.v3i2.1661
Evaluación de la Incertidumbre en la Determinación de Plomo en Sangre por Voltamperometría de Redisolución Anódica, Aplicando el Modelo de Calibración Ponderado de Adición Patrón Generado por Simulación de Monte Carlo
Authors: Delgado Gustavo , Vanegas Manuel , Salazar Jairo
Published: December 2014

El presente trabajo pretende demostrar que la evaluación de la incertidumbre en la determinación de plomo en sangre por voltamperometría de redisolución anódica, aplicando el análisis de regresión lineal ponderado por adición patrón y generado por simulación de Monte Carlo, tiene mayor congruencia con los resultados experimentales que con los obtenidos por la aplicación del enfoque clásico basado en la ley de la propagación de la incertidumbre. Para el primer caso, se elaboró el programa en Maple 13, basado en el algoritmo obtenido del suplemento 1 de la guía GUM 2008, tomando en cuenta tanto las incertidumbres en las lecturas de la señal instrumental como las involucradas en la preparación de las concentraciones de los calibradores. Los valores característicos del plomo para una muestra de sangre fueron: 3.02 μg/dL, con incertidumbre 0.15 μg/dL, con un intervalo de cobertura 2.74 μg/dL a 3.29 μg/dL. Los resultados obtenidos aplicando la ley de propagación de las incertidumbres a partir del modelo clásico de calibración ponderado, fueron los siguientes: 3.08 μg/dL, incertidumbre 0.042, intervalo de cobertura de 3.00 a 3.16 μg/dL. Se observó que hay mayor incertidumbre en el método numérico. No obstante, son coherentes con resultados experimentales de una muestra de sangre.DOI: http://dx.doi.org/10.5377/universitas.v4i1.1675
SURTO DE Salmonella enteritidis/Enteridis EM GRANJA PRODUTORA DE FRANGO CAIPIRA NA REGIÃO SUL DO MARANHÃO
Authors: Pigatto Caroline Peters , Baptista Francisco , Fini Mariana Benitez , Schocken-Iturrino Rubén Pablo
Published: December 2014

Este estudo teve como objetivo detectar o agente responsável pelo elevado índice de mortalidade de pintainhos em propriedade avícola situada na região sul do Maranhão, bem como determinar a fonte de infecção. Foram necropsiados de frangos e realizadas análises bacteriológicas de órgãos, sangue intracardíaco e ração. As amostras provenientes do sangue intracardíaco, dos órgãos e da ração inicial apresentaram colônias características de Salmonella. Estas colônias foram submetidas a provas bioquímicas e sorológicas para comprovação do agente. A salmonelose é considerada uma enfermidade importante na avicultura e pode causar graves perdas ambientais e econômicas, além do problema de saúde pública. Este relato ressalta a importância de um bom manejo sanitário e programas de controle e prevenção de doenças nas criações.
PROTOCOLOS UTILIZADOS EM CONSULTÓRIOS, CLÍNICAS E HOSPITAIS VETERINÁRIOS PARA O CONTROLE DE ENDO E ECTOPARASITAS EM PEQUENOS ANIMAIS EM CURITIBA
Authors: Beirão Breno Castello Branco , Rosinelli Adriana De Siqueira , Da Silva Luana Célia Stunitz , Santos Gizah De Gonçalves Costa , Ruthes Luciane Daemmes , Molento Marcelo Beltrão
Published: December 2014

Tendo-se em vista o alto risco zoonótico das doenças parasitárias e o crescente número de animais de companhia – potenciais transmissores dessas doenças – torna-se mais relevante o conhecimento especializado da área. Na tentativa de controle sobre as parasitoses, os Médicos Veterinários assistiram ao desenvolvimento da resistência dos parasitos frente aos compostos químicos mesmo em pequenos animais, e isso se deve sobretudo à maneira como estas drogas foram utilizadas. O clínico deve ter em mente que, além da saúde animal, deve ocupar-se da saúde humana, esclarecendo os proprietários quanto à problemática das zoonoses. Procurando ter um conceito acerca da atuação dos clínicos veterinários quanto a esse cenário, foram realizadas entrevistas em 120 estabelecimentos veterinários na cidade de Curitiba, PR, entre os meses de abril e maio de 2006. As perguntas envolviam o sexo e idade dos clínicos, o protocolo utilizado por estes contra as doenças parasitárias (principais princípios ativos recomendados pelos entrevistados, duração do tratamento, realização de exames coproparasitológicos para detecção de endoparasitas, raspado e inspeção de pele para verificação de ectoparasitas), parasitos mais comumente encontrados, eficácia e resistência dos antiparasitários e a comercialização destes. Constatou-se que 87,5 % dos entrevistados utilizam o protocolo profilático e supressivo para controlar e erradicar as parasitoses muitas vezes sem a devida exigência técnica, o que predispõe à resistência parasitária. Para se evitar tal quadro os clínicos veterinários devem utilizar de forma consciente os compostos químicos, não abrindo mão do diagnóstico para as doenças parasitárias via exames parasitológicos.
ESTUDO COMPARATIVO E ANÁLISE INTEROBSERVADOR ENTRE DOIS MÉTODOS DE AVALIAÇÂO DA DISPLASIA COXOFEMORAL DE CÃES
Authors: Froes Tilde Rodrigues , Garcia Daniela Aparecida Ayres , Schmidlim Poyanne Crammer , Parchen Helber Daniel , Souza Antônio Carlos Reinaldo
Published: December 2014

Os objetivos desse trabalho foram avaliar as dificuldades da execução do método PennHIP no diagnóstico da displasia coxofemoral, comparar essa modalidade com a empregada pelo CBRV e determinar a influência do treinamento na interpretação por meio de uma análise interobservador. Foram utilizados 15 cães da raça Labrador, realizou-se exame radiográfico conforme as recomendações do CBRV e análise da distração articular. A comparação entre as técnicas se deu de forma subjetiva e pela concordância Kappa(K) quando na análise interobservador. Os valores de foram K= 0,44 moderada pelo método diagnóstico convencional e K=1,0 quase perfeita pelo método PennHIP, todavia, houve maior variabilidade no PennHIP quando na comparação entre os membros. Conclui-se que apesar das dificuldades o método PennHIP deve ser introduzido na rotina de avaliação radiográfica para pesquisa da displasia em conjunto com a avaliação recomendada pelo CBRV.
EFEITOS DA ANGIOTENSINA II NO SISTEMA CARDIOVASCULAR
Authors: Trapp Sílvia Manduca , Vailati Maria do Carmo Fernandez , Matsubara Beatriz Bojikian , Schwartz Denise Saretta
Published: December 2014

A angiotensina II é um importante peptídeo do sistema renina-angiotensina-aldosterona (SRAA). Esse peptídeo tem um papel importante na regulação da pressão sanguínea e homeostase dos fluidos corporais. Contudo, a sua atuação em condições anormais gera efeitos deletérios ao sistema cardiovascular. Resistência vascular, hipertensão, hipertrofia de miócitos, estímulo à produção de radicais livres e substâncias pró-inflamatórias são algumas das ações da angiotensina II que podem resultar no evento denominado de remodelação cardiovascular. Inibidores da enzima conversora de angiotensina (ECA), antagonistas dos receptores de angiotensina, anti-inflamatórios e anti-oxidantes são utilizados clínica e/ou experimentalmente para prevenir ou reduzir os efeitos da angiotensina II. Este trabalho tem como objetivo rever na literatura as ações e interações do peptídeo angiotensina II no sistema cardiovascular. Assim como, as possibilidades terapêuticas empregadas para o controle dos seus efeitos.
Obstacles and Way Forward in Promoting Renewable Energy in Nigeria
Authors: Itodo Isaac N.
Published: December 2014

Nigeria is one of the world’s leading producers of crude oil and yet it is a net importer of refined oil. Its average daily premium motor spirit (PMS) consumption is 30 million liters. At 100% capacity the nation’s refineries will produce 17.74 million liters of premium motor spirit daily. A shortfall of over 10 million liters per day exists. Recent estimates stipulate that Nigeria requires 20,000 MW of electricity per annum. The projected electricity supply from all sources (conventional and renewable) in Nigeria in the short (2007), medium (2015) and long term (2025) is estimated to be 7000 MW, 14000 MW and 29,000 MW respectively. Annual peak electricity demand in Nigeria will increase from 4,558 MW to 45,755 MW in 2050 at high growth rate and 4,558 to 19,599 MW for low growth. Nigeria’s electricity per capita of 27 W/person is not enough to light an electric incandescent bulb of 30 W. These provide enough justification for the use of renewable energy in Nigeria. The use of renewable energy in Nigeria is hindered by the lack of regulation, financial incentives, energy infrastructures, framework for sustainability and technical expertise. Overcoming these obstacles will require invigorating research and development in renewable energy technologies, training and education to build local technical capacity, diversification of energy mix and scaling up of renewable energy utilization, aggressive capacity building in all areas of energy development and creation of enabling environment that will attract investment in energy infrastructure. This paper discusses the obstacles and way forward in promoting renewable energy in Nigeria.
Modeling of Tests of Primary Water Stress Corrosion Cracking of Alloy 182 of Pressurized Water Reactor According to EPRI and USNRC Recommendations
Authors: Aly Omar Fernandes , Neto Miguel Mattar , De Abreu Mendonça Schvartzman Mônica Maria , Lima Luciana Iglésias Lourenço
Published: December 2014

One of the main degradation mechanisms which cause risks to safety and reliability of pressurized water nuclear reactors is the primary water stress corrosion cracking (PWSCC) in nickel alloys, such as Alloy 600 (75Ni-15Cr-9Fe), and its weld metal Alloy 182 (67 Ni-15Cr-8Fe). It can appear at several reactor nozzles dissimilarly welded with Alloys 182/82 between steel ASTM A-508 G3 and stainless steel AISI316L, among others. The hydrogen which is dissolved to primary water to prevent radiolysis, can also have influence on the stress corrosion cracking behavior. In this article one departs from a study of Lima based in experimental data obtained from CDTN-Brazilian Nuclear Technology Development Center, in slow strain rate test (SSRT). It was prepared and used for tests a weld in laboratory, similar to dissimilar weld in pressurizer relief nozzles, operating at Brazilian NPP Angra 1. It was simulated for tests, primary water at 325oC and 12.5 MPa containing levels of dissolved hydrogen: 2, 10, 25, and 50 cm3 STP H2/kgH2O. The objective of this article is to propose an adequate modeling based on these experimental results, for PWSCC crack growth rate according to the levels of dissolved hydrogen, based on EPRI-MRP-263 NP. Furthermore, it has been estimated the stress intensity factor applied for these tests: according with these, some another models described on EPRI-MRP-115, and an USNRC Technical Report, have been tested. According to this study, CDTN tests are adequate for modeling comparisons within EPRI and USNRC models.
La prise de médicaments de façon autonome pour des personnes présentant une déficience intellectuelle
Authors: Lussier-Desrochers Dany , Roux Jeannie , Sparnaay Catherine
Published: December 2014

L’accès au logement est un enjeu majeur afin de promouvoir l’intégration et la participation sociale des personnes qui présentent une déficience intellectuelle (DI). Par contre, cela implique de développer certaines habiletés nécessaires à la réalisation des tâches quotidiennes. Une des inquiétudes soulevées par la vie en appartement est liée à la prise adéquate de médicaments. Cet article présente une recension sur la mise en place d’intervention soutenant la prise de médicaments. Une réflexion sur les enjeux éthiques qui y sont reliés est aussi présentée. Ces éléments permettront de guider les intervenants dans cette sphère d’intervention tout en constituant des assises solides pour les chercheurs voulant développer une programmation de recherche sur le sujet.
L’élève qui a des incapacités intellectuelles et la lecture
Authors: Beaulieu Judith , Langevin Jacques
Published: December 2014

Cet article est une revue de littérature ayant pour thème l’interaction entre la complexité de la tâche qu’est la lecture du français et les caractéristiques des élèves qui ont des incapacités intellectuelles. Pour ce faire, nous avons utilisé une méthode d’analyse de contenu pour examiner cette interaction au regard du modèle explicatif duProcessus de production du handicapproposé par Fougeyrollas, Cloutier, Bergeron, Côté et St-Michel (1998). Selon ce processus, des éléments environnementaux, en interaction avec les déficiences ou incapacités de la personne peuvent devenir des obstacles à la réalisation d’une activité la plaçant ainsi en situation de handicap. Nous pourrons donc montrer comment les processus complexes de lecture risquent de placer la personne ayant des incapacités intellectuelles en situation de handicap, lorsque ces processus de lecture sont en interaction avec les caractéristiques cognitives et non cognitives du lecteur.
Mapping the dynamics of force transduction at cell–cell junctions of epithelial clusters
Authors: Ng Mei Rosa , Besser Achim , Brugge Joan S , Danuser Gaudenz
Published: December 2014

Force transduction at cell-cell adhesions regulates tissue development, maintenance and adaptation. We developed computational and experimental approaches to quantify, with both sub-cellular and multi-cellular resolution, the dynamics of force transmission in cell clusters. Applying this technology to spontaneously-forming adherent epithelial cell clusters, we found that basal force fluctuations were coupled to E-cadherin localization at the level of individual cell-cell junctions. At the multi-cellular scale, cell-cell force exchange depended on the cell position within a cluster, and was adaptive to reconfigurations due to cell divisions or positional rearrangements. Importantly, force transmission through a cell required coordinated modulation of cell-matrix adhesion and actomyosin contractility in the cell and its neighbors. These data provide insights into mechanisms that could control mechanical stress homeostasis in dynamic epithelial tissues, and highlight our methods as a resource for the study of mechanotransduction in cell-cell adhesions.
Chalcophile behavior of thallium during MORB melting and implications for the sulfur content of the mantle
Authors: Nielsen Sune G. , Shimizu Nobumichi , Lee Cin‐Ty A. , Behn Mark D.
Published: December 2014

We present new laser ablation ICP‐MS trace element concentration data for 28 elements in 97 mid‐ocean ridge basalt (MORB) glasses that cover all major spreading centers as well as Tl concentration data for all mineral phases in five lherzolites from the Lherz massif, France. The ratio between the elements thallium (Tl) and cerium (Ce) is nearly constant in MORB, providing evidence that the depleted MORB mantle (DMM) has uniform Ce/Tl. Lherzolite mineral data reveal that sulfides are heterogeneous and contain between 23 and 430 ng/g of Tl while all other minerals contain Tl below the analytical detection limit of ∼1 ng/g. We argue that Tl in MORB is controlled by residual sulfide during mantle melting. To investigate the observed relationship between Tl and Ce, we conduct models of fractional mantle melting, which show that the constant Ce/Tl in MORB is only reproduced if the ratio between clinopyroxene and sulfide in the upper mantle varies by less than 10%. In addition, the rate of melting for these two phases must be nearly identical as otherwise melt depletion and refertilization processes would lead to Ce/Tl fractionation. These model results allow us to establish a relationship for the sulfur content of DMM: [S]DMM = SCSS × Mcpx /Rcpx, where SCSS is the sulfur concentration of a silicate melt at sulfide saturation, Rcpx is the melt reaction coefficient, and Mcpx is the modal abundance of clinopyroxene in the DMM. Using this equation, we calculate that the average upper mantle sulfur concentration is 195 ± 45 μg/g.
Synthesis, characterization and corrosion inhibition in acid medium of l‐histidine Schiff base complexes
Authors: El‐Baradie Kamal Y. , El‐Wakiel Nadia A. , El‐Ghamry Hoda A.
Published: December 2014

Complexes of cobalt(II), nickel(II) and copper(II) of l‐histidine Schiff base derived from 2,4‐dihydroxybenzaldehyde and 2‐hydroxy‐1‐naphthaldehyde have been synthesized. The structures of ligands and complexes have been characterized using elemental analysis, molar conductance, magnetic moment measurements, and spectral and thermal studies. The ligands behave as tridentate, coordinating through the azomethine nitrogen and α‐hydroxyl and carboxylic oxygen atoms. The obtained results show that the Cu(II) complexes have square planar geometry, the Co(II) complexes have octahedral and tetrahedral geometries and the Ni(II) complexes have square planar and octahedral geometries. The molecular geometries of the metal complexes are supported by three‐dimensional molecular modelling using molecular mechanics (MM+) and semiempirical molecular orbital calculations (PM3). The inhibition effect of ligands and complexes on the corrosion of aluminium in 2 M H2SO4 was investigated using weight loss. The inhibition efficiency is found to increase with increasing inhibitor concentration and temperature. The increase in inhibition efficiency with increasing temperature is suggestive of a chemical adsorption process. Copyright © 2014 John Wiley & Sons, Ltd.
Design, synthesis, and photosensitive performance of polymethacrylate‐positive photoresist‐bearing o‐nitrobenzyl group
Authors: Guo Lingxiang , Guan Jing , Zhao Xiaofang , Lin Baoping , Yang Hong
Published: December 2014

Novel polymethacrylate‐positive photoresist‐bearing o‐nitrobenzyl group was described herein. The matrix polymer (PCHIBNB) was synthesized by copolymerization of cyclohexyl methacrylate (CHMA), isobornyl methacrylate (IBMA), and o‐nitrobenzyl methacrylate (NBMA) via reversible addition fragmentation chain transfer (RAFT) polymerization method. After UV irradiation, the o‐nitrobenzyl groups of PCHIBNB were photocleaved and the resulting carboxyl groups were highly alkali‐soluble, so that the matrix polymer could be etched by mild alkali solution with no requirements of photosensitizers or photoacid generators. PCHIBNB was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H‐NMR) spectroscopy, and gel permeation chromatography (GPC). The photocleavable behaviors of PCHIBNB were determined by FTIR, 1H‐NMR, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analysis. The resist formulated with this polymer and cast in tetrahydrofuran (THF) solution showed 10 μm × 10 μm square pattern using a mercury–xenon lamp in a contact printing mode and tetramethyl‐ammonium hydroxide aqueous solution as a developer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41733.
Investigating the reduction in the absorption intensity of P3HT in polymer/fullerene “bilayers” coated using orthogonal solvents
Authors: Zhang Chunmei , Hu Yufeng , Tang Aiwei , Deng Zhenbo , Teng Feng
Published: December 2014

We investigated the reduction in the absorption intensity of poly(3‐hexylthiophene) (P3HT) in a poly(3‐hexylthiophene)/(6,6)‐phenyl‐C61‐butyric acid methyl ester (P3HT/PCBM) “bilayer” heterojunction film that was fabricated using orthogonal solvents. The results show that even though P3HT is insoluble in dichloromethane (DCM), DCM could decrease the chain packing and the crystallinity of the P3HT film by the swelling effect. DCM also assists in the penetration of the PCBM into the P3HT underlayer during spin‐coating. After the DCM evaporates, the PCBM in the P3HT matrix hinders the self‐reorganization of P3HT, causing a drop in the absorption intensity of P3HT. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41757.
Enhancing performance of optical sensor through the introduction of polystyrene and porous structures
Authors: Panawong Chonnakarn , Pandhumas Thidarat , Youngme Sujittra , Martwiset Surangkhana
Published: December 2014

Simple and promising approaches for developing high‐performance Fe3+ sensors were proposed. Polyvinyl chloride (PVC) membrane containing pyrene as a fluorescent indicator was prepared via solvent‐cast method. Upon immersion into 1.0 mM Fe3+ solution, the fluorescence emission of the membrane decreased with the ratio of fluorescence intensities before and after (F0/F) immersion of 1.25. The sensitivity enhancement was achieved through the introduction of polystyrene (PS) onto PVC and the introduction of porous structures. Polyvinyl chloride‐graft‐polystyrene copolymers (PVC‐g‐PS) were synthesized via Atom Transfer Radical Polymerization using PVC as macroinitiator. The grafting percentages of PS on PVC calculated from Nuclear Magnetic Resonance Spectroscopy were 17 and 41. The membrane prepared from low molecular weight copolymer showed higher sensing ability than that from PVC with the F0/F value of 1.39. The increase in PS chain length did not significantly affect the fluorescence quenching. A Stern–Volmer quenching relationship was found with Ksv of 3.96 × 102 M−1. The effect of porous structures on fluorescence quenching was studied by introducing Triton X‐100 as a porogen to PVC/pyrene solution. Attenuated total reflection Fourier transform infrared spectroscopy and Scanning Electron Microscopy analyses confirmed a complete removal of Triton X‐100 after 3 days of immersion in water. The porous membrane demonstrated an enhanced sensing performance with the F0/F value of 1.46. PVC‐g‐PS/pyrene membrane exhibited highly sensitive and selective responses toward Fe3+ over Cu2+, Mg2+, Co2+, Zn2+, Ni2+, and Ag+. In addition, a good reversibility after five cycles of quenching and regeneration was obtained. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41759.
Matching Medline/PubMed data with Web of Science: A routine in R language
Authors: Rotolo Daniele , Leydesdorff Loet
Published: December 2014

We present a novel routine, namely medlineR, based on the R language, that allows the user to match data from Medline/PubMed with records indexed in the ISI Web of Science (WoS) database. The matching allows exploiting the rich and controlled vocabulary of medical subject headings (MeSH) of Medline/PubMed with additional fields of WoS. The integration provides data (e.g., citation data, list of cited reference, list of the addresses of authors' host organizations, WoS subject categories) to perform a variety of scientometric analyses. This brief communication describes medlineR, the method on which it relies, and the steps the user should follow to perform the matching across the two databases. To demonstrate the differences from Leydesdorff and Opthof (Journal of the American Society for Information Science and Technology, 64(5), 1076–1080), we conclude this artcle by testing the routine on the MeSH category “Burgada syndrome.”
Simulated maximum likelihood in autoregressive models with stochastic volatility errors
Authors: Choi Jieun , Chen Bei , Abraham Bovas
Published: December 2014

Autoregressive conditional heteroscedastic type and stochastic volatility (SV) models are designed to analyze and model the conditional variance (volatility), but in some contexts the specification of the conditional mean is also important. In this paper we consider a combination model in which the conditional mean is modeled by an autoregressive (AR) model and conditional variance is modeled by an SV model. We call this model an AR(p)‐SV model, consider some of its properties, discuss its likelihood, and estimate its parameters using simulated maximum likelihood. We also estimate the volatilities by a particle filter. Then these methods are applied to four financial time series. Copyright © 2014 John Wiley & Sons, Ltd.
Mechanistic and conformational studies on the interaction of sulfamethazine with human immunoglobulin G by molecular modeling and multi‐spectroscopic approach in vitro
Authors: Wang Qin , Ge Hongguang , Liu Cunfang , Zhang Shengrui , Tian Guanghui
Published: December 2014

Binding interaction of sulfamethazine (SMZ) with human immunoglobulin G (HIgG) has been explored under physiological conditions. The interaction mechanism was firstly predicted through molecular modeling which showed that several hydrogen bonds participated in stabilizing the SMZ − HIgG complex. Fluorescence spectroscopy, ultraviolet–visible (UV–vis) light absorption and circular dichroism (CD) spectroscopy were used to analyze the binding site, binding constants and effects of SMZ on HIgG stability and secondary structure. The binding parameters and thermodynamic parameters at different temperatures for the reaction have been calculated according to the Scatchard, Sips and Van 't Hoff equations, respectively. Experimental results showed that the quenching mechanism was a static quenching and there was one independent class of binding site on HIgG for SMZ during their interaction. The thermodynamic parameters of the reaction, namely standard enthalpy ΔH0 and entropy ΔS0, had been calculated to be −19.12 kJ · mol−1 and 20.22 J · mol−1 · K−1, respectively, which meant that the electrostatic interaction was the predominant intermolecular force in stabilizing the SMZ − HIgG complex. Moreover, the conformational changes of HIgG in the presence of SMZ were confirmed by three‐dimensional fluorescence spectroscopy, UV–vis absorption spectroscopy and CD spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd.
A liquid chromatography–tandem mass spectrometric assay for the antihypertensive agent azelnidipine in human plasma with application to clinical pharmacokinetics studies
Authors: Gao Yanhui , Li Baoqiu , Zhu Baomeng , Liu Dongming , Zhao Hengli , Fang Zengjun , Wang Haisheng , Lou Hongxiang
Published: December 2014

A robust and sensitive high‐performance liquid chromatographic–tandem mass spectrometric (HPLC‐MS/MS) assay for the high‐throughput quantification of the antihypertensive drug azelnidipine in human plasma was developed and validated following bioanalytical validation guidelines. Azelnidipine and internal standard (IS), telmisartan, were extracted from human plasma by precipitation protein and separated on a C18 column using acetonitrile–methanol–ammonium formate with 0.1% formic acid as mobile phase. Detection was performed on a turbo‐spray ionization source (ESI) and mass spectrometric positive multiple reaction monitoring mode (+MRM) using the respective transitions m/z 583.3 → 167.2 for azelnidipine and m/z 515.3 → 497.2 for IS. The method has a wide analytical measuring range from 0.0125 to 25 ng/mL. For the lowest limit of quantitation, low, medium and high quality controls, intra‐ and interassay precisions (relative standard deviation) were 3.30–7.01% and 1.78–8.09%, respectively. The drug was sufficiently stable under all relevant analytical conditions. The main metabolite of azelnidipine, M‐1 (aromatized form), was monitored semiquantitatively using the typical transition m/z 581.3 → 167.2. Finally, the method was successfully applied to a clinical pharmacokinetic study in human after a single oral administration of azelnidipine 8 mg. The assay meets criteria for the analysis of samples from large research trials. Copyright © 2014 John Wiley & Sons, Ltd.
A rare cause of ascites: pseudomyxoma peritonei and a review of the literature
Authors: Chauhan Abhishek , Patodi Nishant , Ahmed Monz
Published: December 2014

Key Clinical Message

Pseudomyxoma peritonei is rare. The rarity is highlighted by the lack of published evidence regarding management. The latest treatments have altered the prognosis of a once incurable disease. This report serves to both raise awareness and critically appraise the literature regarding the latest management.
Ultrasonic Hot Embossed Polymer Microreactors for Optical Measurement of Chemical Reactions
Authors: Tollkötter Alexander , Sackmann Johannes , Baldhoff Tobias , Schomburg Werner Karl , Kockmann Norbert
Published: December 2014

Ultrasonic hot embossing of polymers is an alternative to reduce fabrication costs of microreactors. An ultrasonic welding machine is used to melt a stack of thermoplastic foils and adapting them to a short‐time milled aluminum mold showing the inversed design of the desired microfluidic cavities. Two micromixers were fabricated this way providing a low degree of axial dispersion and pressure loss. Stability analysis is successfully performed for a wide temperature range and high pressure. Mixing of colored aqueous solutions and neutralization reactions are implemented to both systems for defined volume flow rates and optically investigated via microscope. Reaction progress is automatically determined with a MATLAB script by reference to the consequential color change of the neutralization reaction with a color indicator. Typical mixing characteristics are identified for both mixers.
Slip heating in die drool
Authors: Gilbert Peter H. , Giacomin A. Jeffrey
Published: December 2014

When molten plastic is extruded from a die, it can collect on the open die face. Called die drool, this phenomenon costs plastics manufacturers by requiring shutdown for die cleaning. This has been attributed to cohesive failure within the fluid at an internal surface, where the fluid slips on itself; the corresponding isothermal analysis led to an analytical solution for the drool rate (Schmalzer and Giacomin, J. Polym. Eng. 2013, 33, 1). In this paper, we account for the frictional heating at the cohesive slip interface, which we call slip heating. We focus on slit flow, which is used in film casting, sheet extrusion, curtain coating, and in many other chemical engineering unit operations. In slit flow, the magnitude of the heat flux from the slipping interface is the product of the shear stress and the slip speed. We present the solution for the temperature rise in pressure‐driven slit flow subject to constant heat generation at the cohesive slip interface. We solve the energy equation in Cartesian coordinates for the temperature rise, for both the transient and steady temperature profiles, in both the drool layer and the bulk polymer. We then evaluate the effect of this temperature rise on the rate of die drool. For this simplest relevant non‐isothermal problem, we neglect viscous dissipation and convective heat transfer in the melt and we model viscosity as an Arrhenius function of temperature. We conclude with three worked examples showing the relevance of slip heating in determining die drool flow rates. We find that slip heating diminishes die drool. We arrive at two sufficient dimensionless conditions for the accurate use of our results: Br ≪1 or Gi ≪1.
Tracing Seismic Shortest Path Rays in Anisotropic Medium with Rolling Surface
Authors: Hou‐Yue ZHAO , Mei‐Gen ZHANG
Published: December 2014

It has very important theoretical and practical values to take rolling surface and seismic anisotropy into consideration in seismic forward modeling and inversion. Based on previous researches, the shortest path calculation algorithm is introduced in this paper to calculate seismic travel times in anisotropic media with rolling surface. In the process of model gridding, the whole model is divided into square cells firstly and rolling boundary is regarded as the approximation of units with irregular shapes. Then shortest path calculation is achieved on irregular grids by setting irregular nodes. Sena's group velocity approximation is used to calculate seismic travel times in anisotropic media during ray tracing, and seismic shortest path ray tracing in a complex anisotropic medium with rolling surface is achieved in the end. Theoretical model calculations show that the method in this paper can be reliably applied to complex anisotropic models with higher calculation accuracy.
Dispersion Analysis of Triangle‐Based Finite Element Method for Acoustic and Elastic Wave Simulations
Authors: Shao‐Lin LIU , Xiao‐Fan LI , You‐Shan LIU , Tong ZHU , Mei‐Gen ZHANG
Published: December 2014

Acoustic and elastic wave equations are discretized by finite element method with triangles and central difference scheme in space and time, respectively. The generalized eigenvalue problems are constructed to analyze the numerical dispersion of the finite element method. Three types of mass finite element method, which are consistent finite element method (CFEM), lumped finite element method (LFEM) and mixed finite element method (MFEM), are implemented to the numerical scheme, and the numerical dispersion is under a comprehensive study. Then, the MFEM is adopted to investigate the behavior of numerical anisotropy in terms of four typical triangle meshes. Comparing the numerical dispersion and anisotropy behavior when MFEM uses different interpolation orders, one can easily find that numerical error decreases as the interpolation order increases. Specifically, the numerical dispersion and anisotropy are negligible when third‐order interpolation is used. Finally, controlling the other impact factors, the dispersive properties of elastic wave propagation in elastic medium with various velocity ratios are analyzed, and the results of numerical dissipation are presented at the end of this paper.
Automatic Event Detection and Event Recovery in Low SNR Microseismic Signals Based on Time‐Frequency Sparseness
Authors: Peng WANG , Xu CHANG , Yi‐Bo WANG , Lu‐Chen WANG , Hong‐Yu ZHAI
Published: December 2014

Microseismic monitoring is an effective tool for evaluating the fracturing process and its final results. Event detection is the first step of this monitoring. However, for low SNR microseismic monitoring records, it is difficult to obtain satisfactory results using conventional detection methods. According to time‐frequency sparsness of microseismic events, the Renyi entropy method is used to measure sparseness of microseismic monitor records. A target function of event detection is created which takes the number of low entropy value traces as thresholding under time‐frequency constraint conditions. This method can detect microseismic events and restore clearer microseismic events simultaneously. Tests on synthesis data and real records show that this method has a good performance in processing low‐SNR microseismic records.