bluuebunny/crossref_metadata_2025 huggingface dataset:
Michaelis-Menten Kinetic Parameters of Coconut Coir Enzymatic Hydrolysis
Authors: Fatmawati Akbarningrum , Agustriyanto Rudy
Published: July 2015

The limitation of fossil oil reserves and environmental pollution has been current problems that need to be solved. Biofuels such as ethanol can be alternative energy source that can reduce demand on fossil fuel and environmental problem. Food wastes such as coconut coirs are abundant and contain carbohydrate which can be used as the substrate for biofuel production. Pretreatment and hydrolysis are important stages which have to be applied on such lignocellulose materials before fermentation process to produce biofuel. This article presents Michaelis-Menten kinetic parameters for coconut coir enzymatic hydrolysis. Coconut coirs collected from several local markets in Surabaya were subjected to alkaline pretreatment using 11% sodium hydroxide solution at 121oC. Hydrolysis steps were carried out using commercial enzymes at various initial substrate concentrations. The hydrolysis conditions were at 50oC and pH 4.8. The concentrations of reducing sugar produced in the reactions were measured at certain time intervals. Initial rate of reactions of each reaction batch were then determined. Finally, kinetic parameters of Michaelis-Menten model for enzymatic reaction were determined by fitting the initial rate of reactions and initial substrate concentration data. From nonlinear fitting, the maximum reaction rate (Vm) is 4.9´104 1/h and the value of KM is 4,195 mg/L.
The Effect of Crosslinker and Pore Generated on Selective Adsorbent (Cu2+) based on Grafting of Acrylic Acid onto Cassava Starch
Authors: R. B. Witono Judy , Henrietta Henrietta , Miryanti Y. I. P Arry
Published: July 2015

The technology development in many industries nowadays, such as electronic industry produces heavy metal wastes which may pollute our environment. The use of adsorbent as a heavy metal removal from soil and water is one of the efficient process which can be considered to be used. In addition the release of the adsorbate becomes an important way as well because usually those heavy metals still have a high value. The objective of this research is to develop adsorbent based on cassava starch. So, the release process will become easier and will not produce another waste. The adsorbent was produced through the grafting of acrylic acid onto cassava starch by using Fenton initiator. To construct a stable 3-D network, the crosslinker (CL) N,N’- methylenebisacrylamide was added. The variable observed were the amount of CL added (0.5%; 1.5%; 2.5% and 3.5%) and the treatment of generating more pores on starch copolymer. The treatments on starch copolymer observed were single freezing, second freezing, and citric acid modification and carbonization methods. Analysis performed on the adsorbent was % add-on, water absorption and metal adsorption (especially Cu2+ ion) capacity. The result showed that the used of 2.5% CL produced the highest add-on (47.66 %), the highest water absorption capacity and the highest metal adsorption capacity (0.29g Cu2+/g adsorbent) The citric acid modification also produced the highest pores on the adsorbent.
Optimization of Pyrolysis Operating Condition for Deriving Corn Starch Heterogeneous Acid Catalyst for Biodiesel Production
Authors: Santoso Herry , Michael Christ , Wira Hillman , Inggrid Maria
Published: July 2015

Biodiesel can be produced from various oils and fats. Due to possibility of diversion of edible oils from feedstocks to raw materials for biodiesel production, which may lead to food crisis, it is preferable to choosenon-edible oils as raw material for biodiesel production. As a country rich in natural resources, Indonesia has avast amount and variety of non-edible fatty-oil production plants. However, non-edible oils usually have highfree fatty acid (FFA) contents. Oils with high FFA contents cannot be converted directly to biodiesel using aconventional alkaline catalyzed process due to saponification problem. To avoid this problem, the high FFAcontents in the oils must be reduced via esterification process using acid catalyst. The use of homogeneous acidcatalyst in this process can be very corrosive and not environmentally friendly while the use of commerciallyavailable heterogeneous acid catalyst can be very expensive. In this research, a heterogeneous acid catalystsuitable for biodiesel production will be derived from corn starch through pyrolysis followed by sulphonationprocesses. The purpose of this research is to study the effects of pyrolysis temperature and time to the aciddensity of the catalyst and the activity of the catalyst in the esterification of oleic acid using a 22 factorial designwith 3 center points experimental design. It is found that the catalyst obtained from pyrolysis at 400°C for 15hours has the optimum–HSO3 content of 5.9% which corresponds to the highest average conversion of theesterification of oleic acid of 97.45%.
The Pyrolysis of Glycerol Using Microwave for the Production of Hydrogen
Authors: Qadariyah Lailatul , Mahfud Mahfud , Prihatini Pantjawarni , Hadi Sofyan , Kurniati Yuni
Published: July 2015

The purpose of this research was to study pyrolysis of glycerol to produce hydrogen using microwave. The useof microwave aimed to produce high temperatures, because pyrolysis require high temperature.The effect of kindof catalyst and microwave power were studied. The catalyst was activated carbon and Ni/HZSM-5.The catalystof activated carbon was ready to use, whereas Ni/HZSM-5 catalyst was obtained by ion exchange fromNa-ZSM-5 with NH4Cl and then HZSM-5 was impregnated with metal solution of Ni (NO3)2.6 H2O.Experiments were conducted by mixing catalyst in the reactor together with glycerol solution of 10% (weightpercent) as much as 100 ml. Reactor was made from pyrex and mounted on microwave equipped with athermocouple. And then, reactor was heated on power of 400-700 Watt during thirty minutes. The reactionproduced gases and liquid to be analyzed by chromatography gas.The conclusion stated that microwave couldpyrolysis glycerol into hydrogen. By product of this reaction were methanol, allyl alcohol, acrolein andunidentified products. The difference of catalyst produced different product as well. The pyrolysis of glycerolusing activated carbon produced conversion of 60 %, while using catalysts Ni/HZSM-5 obtained conversion of87 %. The reaction produced hydrogen gases was relatively small for both of catalysts that is minimum of 0,59%and maximum of 0,88%.
Pre-Treatment of Waste Frying Oils for Biodiesel Production
Authors: Puspa Asri Nyoman , Puspita Sari Diah Agustina
Published: July 2015

Synthesis of biodiesel is a strategic step in overcoming energy scarcity and the environmental degradationcaused by the continuous use of the petroleum based energy. Biodiesel as an alternative fuel for diesel engine isproduced from renewable resources such as vegetable oils and animal fats. The main obstacle in the biodieselproduction is the high price of the raw materials, resulting in the price of biodiesel is not competitive comparedto the petroleum diesel. Therefore, the use of waste frying oils (WFO) is one way to reduce the cost of biodieselproduction, because of its availability and low price. In the present work, WFO from California Fried chicken(CFC) restaurants in Surabaya were used as feed stock for the biodiesel production. The experiments wereconducted using three steps of processes: pre-treatment of WFO, preparation of alumina based compositecatalyst CaO/KI/γ-Al2O3 and transesterification of treated WFO. WFO was treated by several types and variousamounts of activated adsobents. The treated WFO was transesterified in three neck glass batch reactor withrefluxed methanol using CaO/KI/γ-Al2O3. The results reveal that the best method for treating WFO is using 7.5%(wt. % to WFO) of coconut coir. Alumina based composite catalyst CaO/KI/γ-Al2O3 was very promising fortransesterification of WFO into biodiesel. The yield of biodiesel was 83% and obtained at 65ºC, 5 h of reactiontime, 1:18 of molar ratio WFO to methanol and 6% amount of catalyst.
Crossing Comb Ridge: Pottery Production and Procurement Among Southeast Utah Great House Communities
Authors: Glowacki Donna M. , Ferguson Jeffrey R. , Hurst Winston , Cameron Catherine M.
Published: July 2015

Understanding how the Chaco regional system operated requires examining the social networks maintained by great house communities during both the peak and decline ofChaco's influence. We used neutron activation analysis (NAA) of pottery, kiln wasters, and clays from three great house communities in southeast Utah (Bluff, Cottonwood Wash, and Comb Wash) to examine pottery production and the interaction networks of their residents. West of Comb Ridge, most gray ware jars or the materials they were made from were imported from east of Comb Ridge in both Chaco and post-Chaco times, while importation of painted white wares changed in the post-Chaco era as local production increased. This counters the expectation that painted pots are more likely to be exchanged than cooking jars. Kiln sherds and prepared clays are shown to be better identifiers of production area than raw clays, and paste color is confirmed as a useful clay source indicator in the Comb Ridge vicinity. Great house communities in the Comb Ridge area continued to exchange pots and/or ceramic raw materials in the post-Chaco era, but there is evidence for shifting social networks and intensified local production of white ware.
Glass is Heavy, Too: Testing the Field-Processing Model at the Modena Obsidian Quarry, Lincoln County, Southeastern Nevada
Authors: Shott Michael J.
Published: July 2015

The field-processing model (FPM) relates degree of resource processing at procurement site to round-trip travel distance. Typically applied to food getting, its extension to stone tools is part of a larger trend to broaden the scope and strengthen the theoretical foundation of inference from lithic data. This trend guided the FPM's application at the Modena obsidian quarry in the Great Basin, which follows earlier analyses by comparing the proportion by reduction stage of biface preforms between quarry and outlying sites and the technological characteristics of debris assemblages. It also uses two ratio-scale methods, slope of the regression of preform weight upon the first principal-component of linear dimensions, which declines with reduction, and slope of cumulative-count of flakes upon flake size, which increases with reduction. Results support the FPM and previous studies that document early-stage reduction at quarries vs. later-stage reduction across the landscape. The essential next step in FPM testing requires data on pattern and extent of biface reduction as a continuous function of distance from source. As useful as are existing measures and approaches, newly defined ratio-scale measures can particularly expedite testing of the FPM in its continuous terms.
Comment on Cook and Comstock's “Evaluating the Old Wood Problem in a Temperate Climate: A Fort Ancient Case Study“
Authors: Hart John P. , Nolan Kevin C.
Published: July 2015

In their recent report, Cook and Comstock (2014) purport to address the "old wood" problem in temperate eastern North America. Here we point out several interpretive and analytical errors in their work. We conclude that careful selection of wood charcoal for radiocarbon assay can result in accurate chronology for events of interest. However, this does not obviate the need to critically assess the extant database of wood charcoal dates in any chronology building effort.
Focusing on the Old Wood Problem: A Response to Hart and Nolan
Authors: Cook Robert A. , Comstock Aaron R.
Published: July 2015

Our recent paper demonstrated that radiocarbon assays sampled from wood charcoal were not systematically skewed when compared to non-wood samples from the same site. This suggests that the “old wood” problem may not be quite as problematic in the temperate Middle Ohio Valley as many suspect. In their comment, Hart and Nolan missed our broader point and mischaracterized our findings. Specifically, we did not suggest that our findings apply to the entirety of eastern North America, nor did we make analytical errors. A thorough reading of our paper clearly supports the following rebuttal. Our main point is that scholars should think twice before discarding radiocarbon dates from wood charcoal, for in some contexts they are the most useful means of determining important chronological information. Despite the suggestion to the contrary, “old wood” concerns do form elements of several hygiene protocols, including Nolan's (2012).
Propuesta de un modelo genérico de análisis de la estructura de las narrativas transmedia / Proposal for a generic model of analysis of the structure of transmedia narratives
Authors: García Carrizo Jennifer , Heredero Díaz Olga
Published: July 2015

Las narrativas transmedia son un fenómeno revolucionario cuya expansión ha sido propiciada por la cultura de la convergencia pero, a pesar de que existen múltiples casos de análisis de las mismas, no se ha consolidado un modelo de estudio integral. El objetivo de esta investigación es establecer un modelo genérico de análisis de la estructura de las narrativas transmedia que es posible aplicar a los diferentes productos transmedia para poder conocer su estructura fijando patrones que permitirán entender mejor su funcionamiento. Para ello, se recurre a la realización de una revisión bibliográfica y un análisis de contenido en el que se examinan los métodos propuestos por varios autores a la hora de describir y estudiar narrativas transmedia y que se toman como punto de partida para la creación de un modelo propio.
Efectos de Internet y las redes sociales en los corresponsales de guerra españoles
Authors: Lavín de las Heras Eva , Römer Pieretti Max
Published: July 2015

La aparición de Internet y las redes sociales han provocado cambios en el paradigma informativo, en la actualidad la información ya no fluye de forma unidireccional, dando lugar a nuevos actores, los llamados periodistas ciudadanos. Pero también, ha obligado a los periodistas profesionales a utilizar estas nuevas herramientas para acercarse al usuario. Son muchos los estudios sobre estos efectos, pero pocos, los que los relacionan con el trabajo de los corresponsales de guerra españoles. Por ello, este artículo pretendemos investigar a través del método cualitativo, con la realización de catorce entrevistas en profundidad,cómo ha afectado a la cobertura de conflictos y en concreto a su trabajo, la aparición de estos nuevos medios.
Socialización virtual, multiculturalidad y riesgos de los adolescentes latinoamericanos en España. Virtual socialization, multiculturalism and risks among Latin American adolescents in Spain.
Authors: Hernández Fernández Coral , Alcoceba Hernando José Antonio
Published: July 2015

El proyecto de investigación “Las relaciones sociales de los jóvenes migrantes en Internet desde la perspectiva de la interculturalidad” (CSO2011- 24376), aborda el estudio de las relaciones presenciales y virtuales como espacios de socialización y riesgo de los adolescentes inmigrantes y autóctonos en España. Este artículo se centra en el análisis del colectivo latinoamericano, en relación a sus particularidades identitarias y culturales. El diseño metodológico utilizado fue de tipo experimental, combinando focus group con cuestionarios autoadministrados y técnicas autoproyectivas iconográficas. Las principales conclusiones apuntan hacia un panamericanismo cosmopolita de los jóvenes latinoamericanos en sus relaciones presenciales, que contrasta con la homogeneidad intercultural respecto a las pautas de uso y control del riesgo en la gestión de sus identidades virtuales, que no difieren de las del resto de jóvenes investigados.
Relaciones e interacciones parasociales en redes sociales digitales. Una revisión conceptual
Authors: Caro Castaño Lucía
Published: July 2015

En este trabajo se realiza una actualización de la noción de interacción y relación parasocial, un concepto acuñado originalmente por Horton y Wohl en 1956 para describir la ilusión de interacción recíproca que muchos miembros de las audiencias experimentaban hacia las figuras mediáticas (celebridades y personajes de ficción), especialmente, de la televisión. A partir de la observación de las prácticas comunicativas que desarrollan los usuarios en los medios sociales, se plantea una reformulación de este concepto clásico para adaptarlo al contexto de estos nuevos espacios.Asimismo, se desarrolla una tipología específica de experiencias parasociales en este contexto y se analiza cómo los usuarios negocian la reciprocidad en la vinculación en un espacio marcadamente público como Twitter, mediante políticas de reciprocidad forzosa en la vinculación como la que expresa la etiqueta #SiMeSiguesTeSigo.
Promoting the use of health information and communication technologies in Spain: a new approach based on the ICT-H
Authors: Blázquez Fernández Carla , Cantarero Prieto David , Pascual Sáez Marta
Published: July 2015

The rapid growth of the use of new technologies is having an important effect on individuals’ health knowledge and behavior. The objective of this paper is to study the potential reduction in health care utilization associated with the expansion of new technologies. Using Spanish micro data from the Survey on the Equipment and Use of Information and Communication Technologies (ICT-H) in Households for 2014 we analyze information technologies equipment, availability of access and means of Internet connection per household. We model the probability of an individual being internet user in Spain as a function of a range of socio-economic characteristics, including individual’s gender, age, education and employment situation. Also, we hypothesized that a greater use of this communication technologies is related to a lesser health care expenditure.
La competencia mediática como reto para la educomunicación: instrumentos de evaluación
Authors:   Universidad de Cantabria, Cantabria, España, García-Ruiz Rosa , Gozálvez Pérez Vicent ,   Universidad de Valencia, Valencia, España, Aguaded Gómez J. Ignacio ,   Universidad de Huelva, Huelva, España
Published: July 2015

Para mejorar el aprendizaje, los avances tecnológicos ponen a disposición de los agentes educativos recursos emergentes, los cuales requieren del desarrollo de competencias o destrezas básicas por parte de los estudiantes y suponen un reto para toda la comunidad educativa. En este contexto, la competencia mediática se convierte en la clave para fomentar un uso responsable, eficiente y democrático de los recursos mediáticos por parte de los ciudadanos. Se presentan aquí los resultados de un proyecto de investigación realizado en España, en el que se han diseñado diversos instrumentos de evaluación de la competencia mediática de estudiantes, profesorado, así como de padres y madres. Su aplicación ha permitido conocer que nos encontramos en un momento extraordinario para aprovechar los recursos mediáticos hacia la mejora del proceso educativo, aunque pone en evidencia que el hecho de estar rodeados de medios y tecnologías no significa que seamos competentes en su uso. Esto nos lleva a insistir en la importancia de la inclusión de la educomunicación dentro del currículum escolar desde las primeras edades.
Salud escolar: una intervención educativa en nutrición desde un enfoque integral
Authors:   Universidad Católica de Córdoba, Córdoba, Argentina, Scruzzi Graciela , Cerbeiro Cynthia ,   Universidad Católica de Córdoba, Córdoba, Argentina, Pou Sonia ,   Universidad Católica de Córdoba, Córdoba, Argentina, Rodríguez Junyent Constanza ,   Universidad Católica de Córdoba, Córdoba, Argentina
Published: July 2015

Este artículo describe una intervención educativa interdisciplinaria, cuyo objetivo fue promover estilos de vida saludables en niños en edad escolar asistentes a una escuela pública de Córdoba, Argentina (2013-2014). El proyecto, destinado a la comunidad escolar y con participación intersectorial, se organizó en tres ejes: diagnóstico de situación (DS), educación alimentaria-nutricional (EAN) y kiosco saludable. El DS supuso un estudio observacional- -analítico sobre el estado alimentario-nutricional en escolares. Se evaluó el proceso y resultados del proyecto. Se encontró que el sobrepeso, ingesta de gaseosas, golosinas y lácteos, así como el kiosco escolar, emergen como tópicos necesarios de abordar en materia nutricional en la población estudiada. Las metas propuestas fueron alcanzadas, se generaron redes y actividades educativas coordinadas e intersectoriales. Se concluye que la familia y la comunidad educativa desempeñan un rol importante en la formación de hábitos alimentarios y se reconoce que la escuela ofrece una oportunidad valiosa para la educación alimentaria nutricional.
La difusión de las causas sociales y su impacto en la percepción de la imagen de marca. El caso español de Televisió de Catalunya
Authors:   Universidad Pontificia Bolivariana, Medellín, Colombia, Orozco Toro Jaime Alberto , Ferré Pavia Carme ,   Universidad Autónoma de Barcelona, Barcelona, España
Published: July 2015

Esta investigación pretende determinar si la difusión de las causas sociales impacta en la percepción de la imagen de marca de una empresa de comunicación. Se sitúa en un marco teórico basado en la publicidad social, imagen de marca, identidad y reputación corporativa, como punto de partida para entender cómo las iniciativas solidarias inciden en la imagen de marca. El trabajo empírico supone la aplicación de 266 encuestas presenciales mediante una pregunta abierta de índole cualitativa, a ciudadanos de la comunidad autónoma de Cataluña (España), respecto a la difusión de una causa social en su televisión pública. Los resultados determinan que la difusión de las causas sociales genera un impacto positivo en la imagen de marca, siempre según la percepción ciudadana. Los televidentes califican como benéficos los esfuerzos que se realizan en esta clase de iniciativas. De esta forma, el vínculo con los stakeholders se afianza a través de este tipo de campañas.
Aprendiendo para la vida: estudio de caso sobre una radio comunitaria online
Authors:   University of Coimbra, Ceis20, CIMJ, Coimbra, Portugal, Santos Sílvio , Brites Maria José ,   Universidade Lusófona do Porto (Portugal), Jorge Ana ,   Universidade Nova de Lisboa (Portugal), Catalão Daniel ,   Universidade Lusófona do Porto (Portugal), Navio Catarina ,   Centro de Investigação Media e Jornalismo (Portugal)
Published: July 2015

En un contexto de disgregación y crisis social, la adquisición de competencias que permitan aumentar las oportunidades de empleo y promuevan una ciudadanía más involucrada se ha ido haciendo cada vez más prioritaria. El proyecto RadioActive Europe surge en este contexto, proponiendo un aprendizaje no formal a partir de una radio ubicada en Internet. Este artículo examina la implantación del proyecto en Portugal, como una iniciativa dirigida a jóvenes en situaciones vulnerables. Se debate el potencial de proyectos de investigación-acción participativa y de la educación para los medios como forma de empoderar a jóvenes en contextos desfavorecidos, como complemento a las limitaciones de la enseñanza formal.
Medios sociales en el periodismo español: Demanda, expectativas y oferta universitaria
Authors:   Universidad de Sevilla, Sevilla, España, Sánchez Gonzales Hada M. , Méndez Muros Sandra ,   Universidad de Sevilla, Sevilla, España
Published: July 2015

Este artículo pretende desvelar si existe una relación proporcional entre las demandas del mercado laboral, las expectativas de los profesionales y la oferta universitaria española en relación con las nuevas figuras profesionales que se han desarrollado en Internet. Hemos empleado la triangulación metodológica mediante la revisión teórica de la literatura sobre el tema, una encuesta a periodistas de medios locales sobre expectativas y usos de medios sociales, y un análisis de magnitud nacional de la oferta de las universidades españolas en grados y másteres de Periodismo. Los resultados revelan que dos tercios de los encuestados están conformes con los nuevos perfiles profesionales y recurren a los medios sociales como herramientas de trabajo. Sin embargo, los planes de estudio universitarios no están apostando de manera contundente por contenidos dirigidos a las nuevas demandas de las empresas periodísticas; por consiguiente, no existe una conexión directa entre el mercado laboral y la oferta universitaria.
Tecnología, redes sociales, política y periodismo. ¿Pluralidad informativa o efecto bumerán?
Authors:   Universitat Autonoma de Barcelona, Barcelona, España, Bernal Triviño Ana Isabel
Published: July 2015

Este artículo realiza un análisis cualitativo, basado en entrevistas en profundidad, de las experiencias que los usuarios tienen en el acceso a la información política en la red. Junto con Internet, las redes sociales han configurado un nuevo espacio no solo de protestas y convocatorias políticas, sino también de acceso a las noticias, creando así una nueva agenda setting, potenciada por la interactividad. Las redes sociales constituyen un nuevo canal educativo para parte de la población que usa esta vía como medio de información y representan una nueva función en la alfabetización mediática, pero su dinámica y funcionamiento pueden potenciar o limitar los contenidos informativos. Los resultados de este estudio exploratorio muestran líneas de investigación y concretan diecisiete prácticas de las tecnologías de la información y comunicación (TIC) en la política y el periodismo, un debilitamiento del malestar mediático frente al impulso de la participación ciudadana y un cuestionamiento de la pluralidad informativa en la red.
La pugna femenina por la equidad laboral. El caso de las primeras comunicadoras en la TV uruguaya
Authors:   Universidad de la República, Montevideo, Uruguay, Graña debut François
Published: July 2015

Este artículo constituye un avance de nuestra investigación sobre mujeres comunicadoras desde la perspectiva de las desigualdades entre hombres y mujeres. Pretendemos aprehender las transformaciones en la vida socioprofesional de las mujeres, tomando por caso la TV uruguaya. Hemos entrevistado a comunicadoras de tres generaciones: las primeras en ingresar a la TV, las profesionales maduras en actividad, y las jóvenes de reciente ingreso. Seguiremos el trayecto profesional de tres pioneras. La primera ingresaba a la TV en sus inicios, a fines de los años cincuenta; la segunda lo hacía en los setenta, y la tercera promediando los ochenta. Hemos preservado el anonimato de las entrevistadas para mayor soltura en el análisis de sus historias de vida. Daremos cuenta de los principales obstáculos y resistencias con que estas mujeres debieron lidiar, poniendo el foco en las relaciones sociales de género.
Desigualdad comunicativa en el repertorio discursivo de la acción colectiva: El caso de #YoSoy132
Authors:   Universidad de Chile, Bacallao-Pino Lázaro M.
Published: July 2015

Este artículo analiza cómo la desigualdad comunicativa media el discurso vinculado a la acción colectiva. A partir de un análisis del caso #YoSoy132, en México (2012), se describe cómo, en un contexto caracterizado por la alta concentración mediática y una singular articulación entre sistema comunicativo dominante y partidos políticos hegemónicos, la democratización de la comunicación deviene una demanda fundamental. Se muestra cómo #YoSoy132 establece vínculos discursivos importantes entre desigualdad comunicativa y desigualdad social en general. Se considera las redes sociales digitales como un recurso central para superar un orden comunicativo desigual, pero también se identifican ciertos desafíos y riesgos asociados al uso de las mismas y a la centralidad de la dimensión comunicativa. Se concluye que la desigualdad comunicativa resulta multidimensional y que su centralidad en el repertorio discursivo del movimiento social #YoSoy132 tiene consecuencias significativas para la acción colectiva y para la propia continuidad del movimiento.
Ascent velocity and dynamics of the Fiumicino mud eruption, Rome, Italy
Authors: Vona A. , Giordano G. , De Benedetti A. A. , D'Ambrosio R. , Romano C. , Manga M.
Published: July 2015

In August 2013 drilling triggered the eruption of mud near the international airport of Fiumicino (Rome, Italy). We monitored the evolution of the eruption and collected samples for laboratory characterization of physicochemical and rheological properties. Over time, muds show a progressive dilution with water; the rheology is typical of pseudoplastic fluids, with a small yield stress that decreases as mud density decreases. The eruption, while not naturally triggered, shares several similarities with natural mud volcanoes, including mud componentry, grain‐size distribution, gas discharge, and mud rheology. We use the size of large ballistic fragments ejected from the vent along with mud rheology to compute a minimum ascent velocity of the mud. Computed values are consistent with in situ measurements of gas phase velocities, confirming that the stratigraphic record of mud eruptions can be quantitatively used to infer eruption history and ascent rates and hence to assess (or reassess) mud eruption hazards.
Internal variability of fine‐scale components of meteorological fields in extended‐range limited‐area model simulations with atmospheric and surface nudging
Authors: Separovic Leo , Husain Syed Zahid , Yu Wei
Published: July 2015

Internal variability (IV) in dynamical downscaling with limited‐area models (LAMs) represents a source of error inherent to the downscaled fields, which originates from the sensitive dependence of the models to arbitrarily small modifications. If IV is large it may impose the need for probabilistic verification of the downscaled information. Atmospheric spectral nudging (ASN) can reduce IV in LAMs as it constrains the large‐scale components of LAM fields in the interior of the computational domain and thus prevents any considerable penetration of sensitively dependent deviations into the range of large scales. Using initial condition ensembles, the present study quantifies the impact of ASN on IV in LAM simulations in the range of fine scales that are not controlled by spectral nudging. Four simulation configurations that all include strong ASN but differ in the nudging settings are considered. In the fifth configuration, grid nudging of land surface variables toward high‐resolution surface analyses is applied. The results show that the IV at scales larger than 300 km can be suppressed by selecting an appropriate ASN setup. At scales between 300 and 30 km, however, in all configurations, the hourly near‐surface temperature, humidity, and winds are only partly reproducible. Nudging the land surface variables is found to have the potential to significantly reduce IV, particularly for fine‐scale temperature and humidity. On the other hand, hourly precipitation accumulations at these scales are generally irreproducible in all configurations, and probabilistic approach to downscaling is therefore recommended.
FINIFLUX: An implicit finite element model for quantification of groundwater fluxes and hyporheic exchange in streams and rivers using radon
Authors: Frei S. , Gilfedder B. S.
Published: July 2015

A quantitative understanding of groundwater‐surface water interactions is vital for sustainable management of water quantity and quality. The noble gas radon‐222 (Rn) is becoming increasingly used as a sensitive tracer to quantify groundwater discharge to wetlands, lakes, and rivers: a development driven by technical and methodological advances in Rn measurement. However, quantitative interpretation of these data is not trivial, and the methods used to date are based on the simplest solutions to the mass balance equation (e.g., first‐order finite difference and inversion). Here we present a new implicit numerical model (FINIFLUX) based on finite elements for quantifying groundwater discharge to streams and rivers using Rn surveys at the reach scale (1–50 km). The model is coupled to a state‐of‐the‐art parameter optimization code Parallel‐PEST to iteratively solve the mass balance equation for groundwater discharge and hyporheic exchange. The major benefit of this model is that it is programed to be very simple to use, reduces nonuniqueness, and provides numerically stable estimates of groundwater fluxes and hyporheic residence times from field data. FINIFLUX was tested against an analytical solution and then implemented on two German rivers of differing magnitude, the Salzach (∼112 m3 s−1) and the Rote Main (∼4 m3 s−1). We show that using previous inversion techniques numerical instability can lead to physically impossible negative values, whereas the new model provides stable positive values for all scenarios. We hope that by making FINIFLUX freely available to the community that Rn might find wider application in quantifying groundwater discharge to streams and rivers and thus assist in a combined management of surface and groundwater systems.
Ring‐Closing Metathesis of (η5‐Alkenylcyclopentadienyl)(alkenylphosphine)manganese(I) Dicarbonyl Complexes
Authors: Tseng Ya‐Yi , Kamikawa Ken , Wu Qian , Takahashi Tamotsu , Ogasawara Masamichi
Published: July 2015

The ruthenium‐catalyzed ring‐closing metathesis (RCM) reactions of various [η5‐(ω‐alkenyl)cyclopentadienyl](ω‐alkenylphosphine)manganese(I) dicarbonyl complexes were examined. The RCM reaction between an η5‐allyl‐ or an η5‐vinyl‐cyclopentadienyl ligand and an allyldiphenylphosphine ligand in the manganese coordination spheres gave the corresponding cyclized products in good to excellent yields. The X‐ray analyses of the two cyclized products revealed the structural differences between the C3‐ and the C4‐bridged complexes. The RCM reactions of the o‐bromo‐substituted manganese complexes were also operative and the cyclized products were obtained in excellent yields of >95%. The preferential formation of the C4‐bridged species over the C3‐bridged analogues in the RCM of the manganese complexes was confirmed by an intramolecular competitive RCM experiment with the [η5‐1‐(methallyl)‐2‐(2‐propenyl)cyclopentadienyl](allyldiphenylphosphine)manganese(I) dicarbonyl complex.

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Recent Progress in Electronic Skin
Authors: Wang Xiandi , Dong Lin , Zhang Hanlu , Yu Ruomeng , Pan Caofeng , Wang Zhong Lin
Published: July 2015

The skin is the largest organ of the human body and can sense pressure, temperature, and other complex environmental stimuli or conditions. The mimicry of human skin's sensory ability via electronics is a topic of innovative research that could find broad applications in robotics, artificial intelligence, and human–machine interfaces, all of which promote the development of electronic skin (e‐skin). To imitate tactile sensing via e‐skins, flexible and stretchable pressure sensor arrays are constructed based on different transduction mechanisms and structural designs. These arrays can map pressure with high resolution and rapid response beyond that of human perception. Multi‐modal force sensing, temperature, and humidity detection, as well as self‐healing abilities are also exploited for multi‐functional e‐skins. Other recent progress in this field includes the integration with high‐density flexible circuits for signal processing, the combination with wireless technology for convenient sensing and energy/data transfer, and the development of self‐powered e‐skins. Future opportunities lie in the fabrication of highly intelligent e‐skins that can sense and respond to variations in the external environment. The rapidly increasing innovations in this area will be important to the scientific community and to the future of human life.
Electronic Bandgap and Exciton Binding Energy of Layered Semiconductor TiS3
Authors: Molina‐Mendoza Aday J. , Barawi Mariam , Biele Robert , Flores Eduardo , Ares José R. , Sánchez Carlos , Rubio‐Bollinger Gabino , Agraït Nicolás , D'Agosta Roberto , Ferrer Isabel J. , Castellanos‐Gomez Andres
Published: July 2015

A study of the electronic and optical bandgap is presented in layered TiS3, an almost unexplored semiconductor that has attracted recent attention because of its large carrier mobility and inplane anisotropic properties, to determine its exciton binding energy. Scanning tunneling spectroscopy and photoelectrochemical measurements are combined with random phase approximation and Bethe–Salpeter equation calculations to obtain the electronic and optical bandgaps and thus the exciton binding energy. Experimental values are found for the electronic bandgap, optical bandgap, and exciton binding energy of 1.2 eV, 1.07 eV, and 130 meV, respectively, and 1.15 eV, 1.05 eV, and 100 meV for the corresponding theoretical results. The exciton binding energy is orders of magnitude larger than that of common semiconductors and comparable to bulk transition metal dichalcogenides, making TiS3 ribbons a highly interesting material for optoelectronic applications and for studying excitonic phenomena even at room temperature.
Design Considerations for Unconventional Electrochemical Energy Storage Architectures
Authors: Vlad Alexandru , Singh Neelam , Galande Charudatta , Ajayan Pulickel M.
Published: July 2015

Batteries have become fundamental building blocks for the mobility of modern society. Continuous development of novel battery chemistries and electrode materials has nourished progress in building better batteries. Simultaneously, novel device form factors and designs with multi‐functional components have been proposed, requiring batteries to not only integrate seamlessly to these devices, but to also be a multi‐functional component for a multitude of applications. Thus, in the past decade, along with developments in the component materials, the focus has been shifting more and more towards novel fabrication processes, unconventional configurations, and additional functionalities. This work attempts to critically review the developments with respect to emerging electrochemical energy storage configurations, including, amongst others, paintable, transparent, flexible, wire or cable shaped, ultra‐thin and ultra‐thick configurations, as well as hybrid energy storage‐conversion, or graphene‐incorporated batteries and supercapacitors. The performance requirements are elaborated together with the advantages, but also the limitations, with respect to established electrochemical energy storage technologies. Finally, challenges in developing novel materials with tailored properties that would allow such configurations, and in designing easier manufacturing techniques that can be widely adopted are considered.
A Transparent Planar Concentrator Using Aggregates of gem‐Pyrene Ethenes
Authors: Banal James L. , White Jonathan M. , Lam Tin Wai , Blakers Andrew W. , Ghiggino Kenneth P. , Wong Wallace W. H.
Published: July 2015

The luminescence properties of pyrene ethenes, both as monomer and aggregate species, are found to depend on the regioisomer structure. Systematic shifts in absorption, emission, and excitation spectra of the gem‐pyrene ethenes, both in solution and in rigid polymer hosts, are consistent with weakly interacting H‐aggregate formation. This aggregation leads to excimer‐like emission with Stokes shifts greater than 1 eV. Planar concentrators fabricated from gem‐pyrene diphenylethenes show comparable performance to previously reported inorganic phosphors. The UV absorption and emission properties of the planar concentrator devices exhibit potential for transparent solar concentrators or visible–blind photodetector applications. This is the first demonstration of exploiting the unusual photophysics of molecular aggregates in planar concentrators.
Refactoring β‐amyrin synthesis in Saccharomyces cerevisiae
Authors: Zhang Genlin , Cao Qian , Liu Jingzhu , Liu Baiyang , Li Jun , Li Chun
Published: July 2015

Triterpenoids are a highly diverse group of natural products and used particularly as medicine. Here, a strategy combining stepwise metabolic engineering and transcriptional control was developed to strengthen triterpenoid biosynthesis in Saccharomyces cerevisiae. Consequently, an efficient biosynthetic pathway for producing β‐amyrin, a commercially valuable compound and precursor of triterpenoids, was constructed through expressing a plant‐derived β‐amyrin synthase. Introducing a heterologous squalene monooxygenase greatly dragged intermediate metabolite squalene toward β‐amyrin. Increasing squalene pool by overexpressing IPP isomerase, FPP, and squalene synthase further enhanced β‐amyrin synthesis of 49‐folds. Through reconstructing the promoters with the binding site of transcription factor UPC2, directed transcriptional regulation on engineered pathway was availably achieved, resulting in β‐amyrin titer increased by 65‐folds. Using ethanol fed‐batch fermentation, β‐amyrin titer was finally improved up to 138.80 mg/L with a yield of 16.30 mg/g dry cell, almost 185 and 232 and folds of the initially engineered strain, respectively. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3172–3179, 2015
Impact of the fluid flow conditions on the formation rate of carbon dioxide hydrates in a semi‐batch stirred tank reactor
Authors: Douïeb S. , Fradette L. , Bertrand F. , Haut B.
Published: July 2015

CO2 hydrate formation experiments are performed in a 20 L semi‐batch stirred tank reactor using three different impellers (a down‐pumping pitched blade turbine, a Maxblend™, and a Dispersimax™) at various rotational speeds to examine the impact of the flow conditions on the CO2 hydrate formation rate. An original mathematical model of the CO2 hydrate formation process that assigns a resistance to each of its constitutive steps is established. For each experimental condition, the formation rate is measured and the rate‐limiting step is determined on the basis of the respective values of the resistances. The efficiencies of the three considered impellers are compared and, for each impeller, the influence of the rotational speed on the rate‐limiting step is discussed. For instance, it is shown that a formation rate limitation due to heat transfer can occur at the relatively small scale used to perform our experiments. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4387–4401, 2015
Scaling inline static mixers for flocculation of oil sand mature fine tailings
Authors: Demoz Alebachew
Published: July 2015

Operations to reclaim mature fine tailings (MFT) ponds involve flocculation using high‐molecular‐weight polymers, for which inline static mixers are suited. Three different commercial static mixers were utilized to determine mixing parameters corresponding to optimal dewatering performance of flocculated MFT. MFT was treated with polymer solution under different mixing conditions. The dewatering rates passed through a peak with increasing mean velocity, V and Reynolds number, Re of the fluid. The greater the number of mixer elements, the lower the V and Re at which the peak dewatering rate occurred. Mixing parameters such as G‐value, residence time, and mixing energy dissipation rate of the most rapidly dewatering flocculated MFT were dependent on mixer type and setup. In contrast, peak dewatering rates converged when scaled with respect to specific mixing energy, E, demonstrating that E is a suitable scale‐up parameter for inline static mixing to produce optimally dewatering MFT. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4402–4411, 2015
The VACTERL Association as a disturbance of cell fate determination
Authors: Lubinsky Mark
Published: July 2015

Cases diagnosed as the VACTERL Association are heterogeneous, and can involve other associations arising from different developmental processes with midline effects. However, these often lack the classic radial ray anomalies that help make VACTERL distinct. A more specific association can be delineated based on teratogenic disturbances affecting vulnerabilities associated with the establishment of cell fate through positional information, with two basic weaknesses: (i) The midline, where topological properties such as reduced lateral information should make information losses more likely; (ii) Increased distal sensitivity at the end of a morphogen gradient in the limbs, where both duplications and deficiencies can arise from similar disturbances. Vertebral, cardiac, anal‐rectal, and tracheo‐esophaeal findings are primary midline derivatives. While the kidneys are bilateral, they can be influenced by the midline, although there may also be effects on the ureteral buds as distal structures. The pre‐axial area is the most distal in limb development, giving radial/tibial deficiencies and duplications. Alternatively, spina bifida and orofacial clefts originate from bilateral structures that are less likely to be affected by problems with midline determination, explaining the rarity of these disorders with VACTERL. Suggested human genetic models typically involve the midline, but lack radial findings, and true Mendelian forms are rare. However, developmental genes such as Sonic Hedgehog may have a pathogenetic role without being causal. © 2015 Wiley Periodicals, Inc.
Oxytocin system social function impacts in children with attention‐deficit/hyperactivity disorder
Authors: Ayaz Ayşe Burcu , Karkucak Mutlu , Ayaz Muhammed , Gokce Sebla , Kayan Esengul , Güler Elif Erol , Güngen Belma Doğan , Kuşcu Tugba Didem , Ocakoğlu Gökhan , Yakut Tahsin
Published: July 2015

To investigate relationships between the polymorphisms and social functioning of children with Attention Deficit/Hyperactivity Disorder (ADHD), according to the polymorphism of three oxytocin receptor (OXTR) genes (rs53576, rs13316193, and and rs2268493). A total of 198 children—studying in the same primary and secondary school and matched in terms of age and gender (99 ADHD, 99 control)—were included in this study. The Schedule for Affective Disorders and Schizophrenia for School‐Age Children‐Present and Lifetime Version was administered to establish the clinical diagnosis. The Social Reciprocity Scale (SRS) was applied to evaluate social functioning. The total genomic DNA was isolated from buccal mucosa samples. No significant differences were determined between the ADHD and control groups in terms of rs2268493, rs13316193, and rs53576 genotype distribution (P = 0.078, P = 0.330, and P = 0.149, respectively). However, the control group T allele frequency in the OXTR Single Nucleotide Polymorphism (SNP) rs2268493 was significantly higher than the ADHD group (P = 0.024). Compared to the control group, the ADHD group had a higher score on the SRS scale (SRS total; Z = −21,135, P < 0.001). No significant difference existed in the SRS scale scores between the children with the T/T genotype and the C allele in the ADHD group (SRS total; Z = −0.543, P = 0.587). The allele distribution of the OXTR gene SNP rs2268493 was significantly different in the ADHD group, compared to the control group. This observation is important in understanding the underlying biological infrastructure in ADHD and developing treatment modalities. © 2015 Wiley Periodicals, Inc.