bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronology of Lake El'gygytgyn sediments
Authors: Nowaczyk N. R. , Haltia E. M. , Ulbricht D. , Wennrich V. , Sauerbrey M. A. , Rosén P. , Vogel H. , Francke A. , Meyer-Jacob C. , Andreev A. A. , Lozhkin A. V.
Published: June 2013

Abstract. A 318 m long sedimentary profile drilled by the International Continental Scientific Drilling Program (ICDP) at Site 5011-1 in Lake El'gygytgyn, Far East Russian Arctic, has been analysed for its sedimentologic response to global climate modes by chrono-stratigraphic methods. The 12 km wide lake is sited in an 18 km large crater that was created by the impact of a meteorite 3.58 Ma ago. Since then sediments have been continuously deposited. For establishing their chronology, major reversals of the Earth's magnetic field provided initial tie points for the age model, confirming that the impact occurred in the earliest Gauss chron. Various stratigraphic parameters, reflecting redox conditions at the lake floor and climatic conditions in the catchment were tuned synchronously to Northern Hemisphere insolation variations and the marine oxygen isotope stack, respectively. Thus, a robust age model comprising more than 600 tie points could be defined. It could be shown that deposition of sediments in Lake El'gygytgyn occurred in concert with global climatic cycles. The upper ~160 m of sediments represent the past 3.3 Ma, equivalent to sedimentation rates of 4 to 5 cm ka−1, whereas the lower 160 m represent just the first 0.3 Ma after the impact, equivalent to sedimentation rates in the order of 45 cm ka−1.
Characterization of groundwater dynamics in landslides in varved clays
Authors: van der Spek J. E. , Bogaard T. A. , Bakker M.
Published: June 2013

Abstract. Groundwater dynamics may play a significant role in landslides. A detailed model is developed of the groundwater dynamics in landslides in varved clays in the Trièves area in the French Alps. The varved clays consist of a sequence of alternating silt and clay layers, covered by a colluvium layer and intersected by fissures. The hydraulic conductivity of the clay layers is negligible compared to the silt layers. It is conceptualized that fissures form a hydraulic connection between the colluvium and the varved clays. Groundwater recharge flows through the colluvium into the fissures, where water is exchanged horizontally between the fissure and the silt layers of the varved clays. Groundwater flow in the colluvium is simulated with the Boussinesq equation, while flow in the silt layers of the varved clays is simulated with the Richards equation. Longitudinal outflow from the fissure is simulated with a linear-reservoir model. Scattered data of relatively short monitoring periods is available for several landslides in the region. A good similarity between observed and simulated heads is obtained, especially when considering the lack of important physical parameters such as the fissure width and the distance between the monitoring point and the fissure. A simulation for the period 1959–2004 showed some correlation between peaks in the simulated heads and the recorded occurrence of landslides, while the bottom of the varved clays remained saturated during the entire simulation period.
"I Always Had My Instrument": The Story of Gabriella Ramires
Authors: Kruse Adam J.
Published: June 2013

The purpose of this instrumental case study is to better understand the academic, social and musical experiences of a Chicana music education student. Semi-structured interviews with a third-generation Chicana student at a Midwestern university explored her academic, social, and musical experiences that preceded her pursuit of an undergraduate music education degree. Due to the current level of academic and social success enjoyed by this student and her access to a wealth of social capital and successful academic models, she is presented as a critical case. Barriers to academic and social pursuits as well as resilience to these barriers related closely to aspects of identity navigation and social capital interaction in this student’s experience. The role of music, music education, and specific music educators acted as crucial ingredients for her eventual success. Implications for music educators and researchers include a call for additional support and greater understanding of potentially marginalized student populations.
Trading Hindemith for "Hugs, High-fives, and Handshakes": One Preservice Music Teacher’s Decision to Teach Elementary General Music
Authors: Shouldice Heather Nelson
Published: June 2013

Existing research suggests that the high school ensemble experience is often a strong influence in the decision to teach music and that the majority of music education students plan to teach in a secondary ensemble setting. The purpose of this instrumental case study was to explore the experiences and beliefs of one male undergraduate music education student who chose a student-teaching placement (and subsequent career) in an elementary general music setting rather than his original intent to become a band director. Analysis of interviews, email correspondence, teaching videos, and journal entries revealed four emergent themes in his decision to teach elementary general music: (a) the influence of undergraduate coursework, (b) the participant’s tendency to be student-centered, (c) the need for broadening students’ musical skills and understanding, and (d) dissatisfaction with the current band culture. Findings suggest that music teacher education and future music education research might focus on teacher/director role perceptions, beliefs about the purpose of music education, and critical incidents that can impact career decisions in preservice music teachers, as well as the role of music education coursework in music teacher identity development.
A nova velhice do provedor
Authors: Cardoso Guirra Santana Nívia , Sampaio Oliveira Lima Isabel Maria
Published: June 2013

A longevidade e a melhora da qualidade de vida da população idosa produziram reflexos em diversos setores da sociedade, inclusive nas formações familiares. A imagem dos idosos como dependentes, passa a ser relativizada por outras imagens que afirmam o papel do idoso participativo no âmbito social, econômico e afetivo. O objetivo do presente estudo é discutir o papel do idoso na sociedade contemporânea enquanto protetor da infância. A estratégia metodológica adotada foi de natureza qualitativa, com revisão de literatura e utilização dos dados do Instituto Brasileiro de Geografia e Estatística (CENSO, PNAD e PEA). Os resultados indicam que, não obstante a importância do tema, tímida é a produção científica brasileira a respeito da guarda de crianças e adolescentes por seus avós, entendida como mecanismo de proteção infantil desenvolvido nas relações familiares intergeracionais.
Digressões sobre saúde, envelhecimento e vida saudável na contemporaneidade
Authors: Cerqueira Monique Borba
Published: June 2013

Na busca por uma vida saudável se reprograma o corpo, o comportamento e os modos de vida do envelhecimento contemporâneo. O processo de envelhecer tem sido objeto de inúmeras práticas vinculadas ao discurso médico do “envelhecimento saudável”, na tentativa de maximizar a saúde e as condições de vida dos mais velhos. Segundo o envelhecimento ativo, o envelhecer é equacionado a partir da entronização do rejuvenescimento, no qual os mais velhos devem recuperar espaços produtivos, praticar atividades físicas e autorregular a própria saúde em busca do equilíbrio orgânico e da aparência jovial. Este artigo discorre sobre as transformações operadas pelas novas tecnologias da saúde em nosso tempo e seus rebatimentos nos modos de envelhecer.
Para alimentar o mundo: modificações genéticas, (in) segurança alimentar e os riscos para a saúde humana e ambiental
Authors: Ferreira J. Flávio
Published: June 2013

Neste trabalho pretende-se tecer breves reflexões acerca da segurança alimentar face à utilização das chamadas “tecnologias transgênicas” que marcaram a Nova Revolução Verde (a 2º R.V.) desde a década de 1990. No cerne do debate está uma crítica epistemológica aos paradigmas que projetam na relação do humano com a natureza (aqui destacada pela produção de alimentos) ideários de produtividade, dominação e de livre manipulação do meio-ambiente. Os benefícios emergentes de tais práticas nos discursos econômicos e políticos contrastam com os indícios de riscos à saúde humana ancorados em testes científicos: mais do que um movimento humanitário de “combate à fome”, as políticas atuais de segurança alimentar vêm se apresentando como resultado prático de uma leitura [cientificista] da realidade tributária de paradigmas fundamentados em outras formas (proto)capitalistas do passado, como o colonialismo/imperialismo. Para entender este fenómeno de forma ampla, uma crítica epistemológica faz-se imperativa.
Solving Supersymmetric Hirota–Satsuma Equation by a Direct Bosonization Approach
Authors: Liu Xi-Zhong , Yu Jun
Published: June 2013

The N = 1 supersymmetric Hirota-Satsuma equation is transformed into systems of coupled bosonic equations by expanding fermionic superfield in terms of 2, 3, and n(n ≥ 4) Grassmann parameters, respectively. Taking advantage of the resulting coupled bosonic systems being linear in the undetermined variables, the supersymmetric Hirota-Satsuma equation is solved out by using the mapping and deformation method. Besides, the richness of the localized excitations of the supersymmetric integrable system is discovered.
Theoretical Studies on the Local Structure and Electron Paramagnetic Resonance Parameters for Cu2+ Centers in TiO2 with one Oxygen Vacancy Adjacent
Authors: Li Chao-Ying , Zheng Xue-Mei , He Jie
Published: June 2013

Based on the defect model that the impurity Cu2+ in TiO2 on the octahedral Ti4+ site is associated with one oxygen vacancy VO along the C
2 axis, the electron paramagnetic resonance (EPR) parameters, i. e., the g factors gi (i = x;y; z) and the hyperfine structure constants At, of the Cu2+-VOcenter in TiO2 are calculated by using the perturbation formulas of these parameters for a 3d9 ion in a rhombically elongated octahedra. From this study, the impurity Cu2+ is found to be away from VO by a distance Dz (≈ 0:33 Å) along the C2 axis, meanwhile the four O2- ions in the plane perpendicular to the C2 axis may be shifted by Dx (≈ 0:28 Å) towards VO due to the electrostatic interaction between these ions and VO. The theoretical results based on the above local structure distortions show good agreement with the experimental data.
Bioesai bioinsektisida Beauveria bassiana dari Sumatera Selatan terhadap kutu putih pepaya, Paracoccus marginatus Williams & Granara De Willink (Hemiptera: Pseudococcidae)
Authors: Herlinda Siti , Darmawan Komang Agus , Firmansyah Firmansyah , Adam Triani , Irsan Chandra , Thalib Rosdah
Published: June 2013

Kutu putih pepaya, Paracoccus marginatus (Hemiptera: Pseudococcidae) di lahan rawa lebak Sumatera Selatan, dapat menyebabkan banyak tanaman pepaya muda yang mati dan kualitas buah menurun. Penelitian ini bertujuan untuk menguji bioesai formulasi Beauveria bassiana terhadap nimfa P. marginatus. B. bassiana diperbanyak pada media beras. Bahan pembawa yang digunakan adalah kompos, kompos kering, abu sekam, dedak, serbuk kayu, dedak dicampur dengan serbuk kayu, kompos diperkaya dengan Trichoderma virens. Kontrol yang digunakan ada dua macam, yaitu air steril (kontrol 1) dan isolat B. bassiana (kontrol 2). Viabilitas konidia B. bassiana pada kontrol 2 tertinggi (46,33%) dibandingkan dengan perlakuan lain. Viabilitas konidia kontrol 2 tersebut tidak berbeda nyata dengan formulasi dengan bahan pembawa dedak, dedak campuran serbuk kayu, dan kompos diperkaya T. virens. Mortalitas nimfa P. marginatus tertinggi (82,86%) terjadi pada formulasi dengan bahan pembawa kompos diperkaya dengan T. virens dan berbeda nyata dibandingkan dengan perlakuan lainnya. Mortalitas nimfa terendah (73,48%) terjadi pada formulasi abu sekam dan berbeda nyata dibandingkan dengan perlakuan lainnya. Mortalitas kontrol ratarata 29,52% pada kontrol 1, sedangkan pada kontrol 2 rata-rata 75,71%. Median lethal time (LT50) tersingkat (3,55 hari) ditemukan pada formulasi kompos diperkaya dengan T. virens, sedangkan terlama (3,73 hari) ditemukan pada formulasi abu sekam. Dengan demikian, bioinsektisida yang paling efektif adalah formulasi kompos diperkaya dengan T. virens.
Comunicación y democracia en el entorno digital
Authors: Zallo Elguezabal Ramón
Published: June 2013

Desde una mirada holística, crítica y constructiva, se analizan los lazos de la comunicación y la cultura con la democracia de nuestro tiempo. Para ello se describen algunos cambios sistémicos, incluida la crisis democrática, y que configuran el contexto para cualquier actividad. Se apuntan algunos problemas de la comunicación en lo que es una época de transición de la cultura y comunicación analógicas a la cultura y comunicación digitales, se comparan los rasgos ya presentes y algunas tendencias en la era digital. Respecto a la democracia, se diagnostican algunas problemáticas y se sugiere la utilidad de algunas herramientas comunicativas para el paso de una democracia representativa a una democracia relacional. Un impulso de la democratización significa también repensar un modelo de comunicación acorde.
El empoderamiento digital de niños y jóvenes a través de la producción audiovisual
Authors: Aguaded José Ignacio , Sánchez Carrero Jacqueline
Published: June 2013

Los niños, adolescentes y jóvenes del presente siglo están transitando su andadura por la producción audiovisual de modo cada vez más práctico. Reclaman un espacio propio haciendo oír sus voces en el mundo digital. La capacidad que están desarrollan no solo a través de la producción audiovisual sino también en la recepción crítica de los contenidos de las pantallas genera en ellos importantes descubrimientos acerca de la industria de los medios de comunicación. En este artículo nos adentramos en el concepto de educación mediática describiendo el proceso y el resultado de una investigación realizada con niños de 7 a 11 años de edad acerca del universo que existe detrás de las cámaras de televisión. En la experiencia ellos son creadores, escriben sus guiones, graban con cámara de vídeo, editan digitalmente y se ejercitan, a la vez, en la lectura crítica de dibujos animados, series, películas y anuncios publicitarios. Por último, mostramos el enfoque de la llamada Generación M2, niños y jóvenes que están viviendo un proceso de empoderamiento proporcionado por el uso creativo y participativo de los medios digitales.
Percepción de la publicidad en tabletas digitales. Estudio comparado de las ediciones en iPad y en papel de un diario.
Authors: Quintas Froufe Natalia , Sanjuán Pérez Antonio , Martínez Costa Sandra
Published: June 2013

Este artículo recoge los resultados de un estudio experimental sobre la percepción que tiene el usuario/lector de la publicidad en un diario impreso y en su versión adaptada a la tableta digital (iPad). El trabajo compara los niveles de recuerdo, visibilidad y rechazo de los anuncios en la tableta frente a los incluidos en soporte papel. El objetivo es el de identificar los formatos publicitarios más eficaces para la tableta digital, dadas sus especificidades de uso, interactividad y tamaño. El estudio se centra en la percepción de los formatos publicitarios para iPad con un menor nivel de interactividad, ya que muchos periódicos para tableta utilizan versiones enriquecidas del papel a los que incorporar links o fotografías y vídeos, en lugar de hacer una aplicación específica para estos dispositivos. Por lo tanto, los formatos estudiados son aquellos derivados de los habituales de la prensa en papel. Los resultados indican que por el momento en este tipo de formatos publicitarios no existen diferencias significativas en cuanto a la percepción que el usuario/lector tiene de ella.
El friulano como resistencia de la identidad: Pasolini y Casarsa Della Delizia.
Authors: Rey Mimoso-Ruiz Bernadette
Published: June 2013

En un momento en que Europa, la Unión Europea, representa una auténtica encrucijada donde se conjugan naciones, estados, culturas, lenguas… las maneras en que la universalidad del arte y la especificidad del idioma componen sus fuerzas respectivas —en unas tensiones tal vez, y a la vez, inevitables, necesarias, destructivas, productivas— suponen una llamada de atención para pensar la complejidad de las formas de comunicación en relación a las vías de acción política, a la vez que a los residuos psico-ontológicos e históricos de la condición original de toda producción cultural. Encontramos un vivo ejemplo de esta complejidad y de aquella composición de fuerzas en lo que supuso la producción poética temprana de uno de los talentos contemporáneos más polifacéticos y controvertidos, Pier Paolo Pasolini. Sus prácticas literarias, artísticas, existenciales, encuentran desde sus inicios —pero impregnan también todo el devenir de su obra— un factor a la vez de resistencia y de acción en la  forma misma de su expresión a través de un idioma —el friulano— que atestigua la externalidad de una lucha geopolítica e histórica enlazada a una interioridad psico-genealógica. Todo lo cual nos puede aportar claves para comprender mejor nuestro tiempo —la idea misma de una Italia siempre convulsa (como hoy sigue siéndolo), de una España tensionada también por lenguas e identidades, de una Europa caleidoscópica— así como para conocer mejor al inconmensurable Pasolini desde su temprana emergencia. Todo ello en relación a las prácticas comunicativas, artísticas, culturales, ideológicas, identitarias…
Esto ya ha pasado: desafíos y transformaciones del medio radiofónico en la sociedad reticular.
Authors: Arnau Roselló Roberto
Published: June 2013

Introducción a la sección Tribuna de adComunica.
Las sinergias, un reto para RTVE.
Authors: Marimón Andrés Ignacio
Published: June 2013

Artículo para la sección Tribuna de adComunica.
El periodista analógico en la era digital.
Authors: Lluch Pilar
Published: June 2013

Artículo para la sección Tribuna de adComunica.
La radio en la era de la sociedad digital
Authors: Barrios Rubio Andrés
Published: June 2013

El ser humano de hoy está en un entorno de redes de comunicación y colaboración en el que se imponen modelos de sindicalización, afiliación, agregación y comunidades a través de portales, foros, blogs y demás mecanismos multimedia que ofrecen la interactividad entre usuarios y medios. Las audiencias dejaron de ser pasivas para convertirse en productoras de información, comunicación y contenidos; más que receptores de un medio son usuarios de un servicio con el cual deciden interactuar. De todo lo anterior surge el cuestionamiento del papel de los medios frente a dichas redes en su actuar diario y la relación con el entorno y las audiencias. Para el caso particular de esta investigación se ha querido centrar la mirada en el medio de mayor aceptación en Colombia, la radio, bajo el interrogante: ¿Cómo influencian las redes sociales la creación de contenidos y el establecimiento de la agenda radial colombiana? Ello implica hacer referencia al criterio periodístico en la selección de la información, los nuevos valores de la comunicación entre el medio y sus usuarios, y la construcción de una serie de redes en las que sus audiencias participan abiertamente con los medios.
Presente y futuro de la radio digital: factores tecnológicos determinantes en su adopción y desarrollo
Authors: Amieva de la Vega Rebeca , Bolea de Anda Adelaida , Huerta José María
Published: June 2013

Este trabajo de investigación tiene como objetivo realizar un balance panorámico del mundo de la radio digital, a partir del análisis de diferentes estudios sobre la situación actual y perspectivas del sector radiofónico. Estos estudios han sido llevados a cabo por distintos organismos internacionales y nacionales, en algunos casos, de difusión exclusiva entre sus socios. Se han tenido en cuenta las aportaciones obtenidas del contacto directo con responsables y profesionales de primer nivel. Entre nuestros objetivos, también está aclarar algunos conceptos clave (DAB, DRM, EURO-CHIP, DNS), necesarios para comprender la actualidad de la radio digital desde un punto de vista técnico.
Transformaciones en el Tercer Sector: el caso de las radios comunitarias en España.
Authors: García-García Javier
Published: June 2013

Tradicionalmente los medios de comunicación han sido un espacio acaparado por los gobiernos y las empresas. Pero al marguen de estos grandes medios la ciudadanía ha buscado sus propios espacios de expresión. La ciudadanía no quiere limitarse a ser un mero consumidor y ha ido creando sus propios medios de comunicación como publicaciones, radios o televisiones. Esta participación ciudadana ha cobrado especial intensidad en las últimas décadas con la aparición de Internet, pero nos encontramos con multitud de experiencias previas que ya venían apuntando cuales eran las necesidades de comunicación de los distintos grupos sociales. Una de las experiencias que nos encontramos son las llamadas radios libres y comunitarias, cuya historia corre de forma paralela a la historia de la democracia española. Con la llegada de los nuevos medios de comunicación estas emisoras son vistas como una reliquia del pasado que ha quedado superada por las posibilidades que Internet ofrece a la ciudadanía para crear sus propios medios de comunicación. El presente texto se aborda la problemática legal del Tercer sector audiovisual y se analiza la el caso de las radios libres y comunitarias en España, en espacial se pone el foco en la relación de estas emisoras con Internet y las redes sociales. El artículo apunta al carácter poco democrático que ha caracterizado las políticas de comunicación en España lo que ha impedido el desarrollo de un Tercer Sector Audiovisual y plantea algunos retos e incógnitas para el futuro de las radios comunitarias.
Si hay otros mundos, se linkan en este
Authors: Fernández Fernández Césareo
Published: June 2013

Introducción de la sección Otras Investigaciones de adComunica.
El rol de las variables de nivel individual en la formación de capital social organizativo. El caso de una microempresa de base tecnológica
Authors: Roman Castillo Ruth Esperanza , Smida Ali
Published: June 2013

La noción de “capital social organizativo” (CSO) exalta los beneficios del desarrollo y mantenimiento de relaciones sociales internas y externas de calidad por una empresa. Este artículo presenta el caso de « Kirvit Ltda », una microempresa de base tecnológica colombiana. El objetivo es analizar los momentos de formación de CSO que acompañan la innovación de uno de sus productos, focalizados sobre la acción de tres variables llamadas “de nivel individual”. El tipo de empresa analizado se utiliza igualmente para reflexionar sobre las particularidades de la formación de CSO con respecto al tamaño y naturaleza de la empresa.
Using the iPlant Collaborative Discovery Environment
Authors: Oliver Shannon L. , Lenards Andrew J. , Barthelson Roger A. , Merchant Nirav , McKay Sheldon J.
Published: June 2013

The iPlant Collaborative is an academic consortium whose mission is to develop an informatics and social infrastructure to address the “grand challenges” in plant biology. Its cyberinfrastructure supports the computational needs of the research community and facilitates solving major challenges in plant science. The Discovery Environment provides a powerful and rich graphical interface to the iPlant Collaborative cyberinfrastructure by creating an accessible virtual workbench that enables all levels of expertise, ranging from students to traditional biology researchers and computational experts, to explore, analyze, and share their data. By providing access to iPlant's robust data‐management system and high‐performance computing resources, the Discovery Environment also creates a unified space in which researchers can access scalable tools. Researchers can use available Applications (Apps) to execute analyses on their data, as well as customize or integrate their own tools to better meet the specific needs of their research. These Apps can also be used in workflows that automate more complicated analyses. This module describes how to use the main features of the Discovery Environment, using bioinformatics workflows for high‐throughput sequence data as examples. Curr. Protoc. Bioinform. 42:1.22.1‐1.22.26. © 2013 by John Wiley & Sons, Inc.
Phylogenetic Analysis with the iPlant Discovery Environment
Authors: Matasci Naim , McKay Sheldon
Published: June 2013

The iPlant Collaborative's Discovery Environment is a unified Web portal to many bioinformatics applications and analytical workflows, including various methods of phylogenetic analysis. This unit describes example protocols for phylogenetic analyses, starting at sequence retrieval from the GenBank sequence database, through to multiple sequence alignment inference and visualization of phylogenetic trees. Methods for extracting smaller sub‐trees from very large phylogenies, and the comparative method of continuous ancestral character state reconstruction based on observed morphology of extant species related to their phylogenetic relationships, are also presented. Curr. Protoc. Bioinform. 42:6.13.1‐6.13.13. © 2013 by John Wiley & Sons, Inc.
Creating Databases for Biological Information: An Introduction
Authors: Stein Lincoln
Published: June 2013

The essence of bioinformatics is dealing with large quantities of information. Whether it be sequencing data, microarray data files, mass spectrometric data (e.g., fingerprints), the catalog of strains arising from an insertional mutagenesis project, or even large numbers of PDF files, there inevitably comes a time when the information can simply no longer be managed with files and directories. This is where databases come into play. This unit briefly reviews the characteristics of several database management systems, including flat file, indexed file, relational databases, and NoSQL databases. It compares their strengths and weaknesses and offers some general guidelines for selecting an appropriate database management system. Curr. Protoc. Bioinform. 42:9.1.1‐9.1.10. © 2013 by John Wiley & Sons, Inc.
Photoluminescence of as‐synthesized and heat‐treated phenyl‐containing polysilylcarbodiimides: role of crosslinking and free carbon formation in polymer‐derived ceramics
Authors: Mera Gabriela , Menapace Ilaria , Widgeon Scarlett , Sen Sabyasachi , Riedel Ralf
Published: June 2013

For the first time, photoluminescence properties of four polysilylcarbodiimides, comprised of a phenyl pendant group attached at the silicon atom and a second substituent being either phenyl (S1), methyl (S2), hydrogen (S3) or vinyl (S4), are reported. Distinctive fluorescence emissions are detected in the polymers with one phenyl group at the silicon atom (S2, S3 and S4), due to a phenyl excimer emission. The polymer with two phenyl groups attached at the same silicon atom (S1) shows, besides the phenyl excimer emission, also a vibrationally structured emission stemming from the Ph‐SiX2‐Ph unit. Moreover, the polysilylcarbodiimides were heat‐treated at different temperatures up to 500°C in argon flow. In this case, the amount of crosslinking is identified to be responsible for a bathochromic shift of the maximum emission spectra with increasing annealing temperature. After annealing at 300°C, polymers S2 and S3 present a red‐shifted emission due to rearrangement reactions of the basic polymer structure. Furthermore, the presence of free carbon formed during the annealing procedure in the form of polycyclic aromatic hydrocarbons, as well‐defined fragments of graphene, are proven to contribute to the photoluminescence properties of the heat‐treated polysilylcarbodiimides. Copyright © 2013 John Wiley & Sons, Ltd.
Cell‐Based Proteome Profiling Using an Affinity‐Based Probe (AfBP) Derived from 3‐Deazaneplanocin A (DzNep)
Authors: Tam Eric K. W. , Li Zhengqiu , Goh Yi Ling , Cheng Xiamin , Wong Sze Yue , Santhanakrishnan Sridhar , Chai Christina L. L. , Yao Shao Q.
Published: June 2013

3‐Deazaneplanocin A (DzNep), a global histone methylation inhibitor, has attracted significant interest in epigenetic research in recent years. The molecular mechanism of action and the cellular off‐targets of DzNep, however, are still not well‐understood. Our aim was to develop novel DzNep‐derived small‐molecule probes suitable to be used in live mammalian cells for identification of potential cellular targets of DzNep under physiologically relevant settings. In the current study, we have successfully designed, synthesized, and tested one such probe, called Dz-1. Dz-1 is a ‘clickable’ affinity‐based probe (AfBP) derived from DzNep with minimal structural modifications. The probe was found to be highly cell‐permeable, and possessed similar anti‐apoptotic activities as DzNep in MCF‐7 mammalian cells. Two additional control probes were made as negative labeling/pull‐down probes in order to minimize false identification of background proteins due to unavoidable, intrinsic nonspecific photo‐crosslinking reactions. All three probes were subsequently used for in‐situ proteome profiling in live mammalian cells, followed by large‐scale pull‐down/LC‐MS/MS analysis for identification of potential cellular protein targets that might interact with DzNep in native cellular environments. Our LC‐MS/MS results revealed some highly enriched proteins that had not been reported as potential DzNep targets. These proteins might constitute unknown cellular off‐targets of DzNep. Though further validation experiments are needed in order to unequivocally confirm these off‐targets, our findings shed new light on the future use of DzNep as a validated chemical probe for epigenetic research and as a potential drug candidate for cancer therapy.
A Robust Tracking Control for a Class of Uncertain Chaotic Systems
Authors: Chang Yeong‐Chan
Published: June 2013

This paper addresses the problem of designing robust tracking control for a large class of uncertain nonlinear chaotic systems. This class of chaotic systems can be perturbed simultaneously by plant uncertainties, unmodeled time‐varying perturbations, time delays, and external disturbances. Through the backstepping design procedure and suitably choosing the Lyapunov–Krasovskii functionals, a hybrid adaptive robust tracking control scheme is developed such that all of the states and signals of the closed‐loop system are bounded and the tracking error is uniformly ultimately bounded. Consequently, the control scheme developed here can be extended to handle robust tracking control for a broader class of perturbed nonlinear chaotic systems involving a significant degree of uncertainty. Finally, a simulation is made to demonstrate the effectiveness of the proposed control algorithms.
In silico design and construction of metal‐binding hybrid proteins for specific removal of cadmium based on CS3 pili display on the surface of Escherichia coli
Authors: Eskandari Vajiheh , Yakhchali Bagher , Sadeghi Mehdi , Karkhane Ali Asghar
Published: June 2013

In this study, through a combination of bioinformatics and genetic engineering procedures, high‐affinity metal‐binding peptides were designed and expressed on the surface of Escherichia coli for selective Cd2+ adsorption. Putative cadmium‐binding motifs were identified by searches against the Prosite database and permissive sites in the major subunit (CstH) of the enterotoxigenic E. coli pili were predicted based on the data derived from modeling of 3D structures, secondary structure prediction and assignment, inspection of protein hydropathy and exposed regions, and also protein interaction sites. The metal‐binding motifs were inserted into one permissive site of the CstH (amino acid 38) with the aid of the SOEing PCR technique. The capacity and selectivity of the recombinant bacteria displaying hybrid pili to adsorb cadmium were evaluated with the atomic absorption procedure. The levels of Cd2+ accumulation in the recombinant E. coli strains were 13.9‐ and 11.33‐fold higher than those in the control strain. Cd2+ was selectively absorbed from a solution containing equal concentrations of four metals, resulting in more than 90% of the total adsorbed metals being Cd2+, showing a relatively high affinity for Cd2+ over other coexisting metal ions.
Experimental characterization of next‐generation expanded‐bed adsorbents for capture of a recombinant protein expressed in high‐cell‐density yeast fermentation
Authors: Kelly William , Garcia Phillip , McDermott Stefanie , Mullen Peter , Kamguia Guy , Jones Gerard , Ubiera Antonio , Göklen Kent
Published: June 2013

Expanded‐bed adsorption (EBA) can be particularly useful in protein recovery from high‐cell‐density fermentation broth where conventional methods for harvest and clarification, such as continuous centrifugation and depth filtration, demand long processing times and are associated with high costs. In this work, the use of next‐generation high‐particle‐density EBA adsorbents, including two mixed‐mode resins, for the direct capture of a recombinant protein expressed in yeast at high cell densities is evaluated. Using classical experimental approaches and under different conditions (pH, salt, etc.), Langmuir isotherm parameters for these resins are obtained along with pore diffusivity values. Additional batch adsorption studies with Fastline® MabDirect, the resin that demonstrated the highest static binding capacity for the recombinant protein of interest under the conditions evaluated in this study, indicate competitive binding of nontarget proteins and approximately a 30% reduction in equilibrium binding capacity to 50 mg/mL settled bed in the presence of a 5%–10% cell concentration. Packed‐bed (PB) dynamic binding capacities for the MabDirect resin (25–40 mg/mL PB) were significantly higher than for the Fastline® HSA resin and for the MabDirect MM resin in expanded‐bed mode (5–10 mg/mL settled bed). Bed expansion behavior for the mMabDirect MM resin along with process yield and eluate purity are identified as a function of linear velocity and cell density, demonstrating process feasibility for pilot scale use.
Dorsal and ventral stimuli in sandwich‐like microenvironments. Effect on cell differentiation
Authors: Ballester‐Beltrán José , Lebourg Myriam , Salmerón‐Sánchez Manuel
Published: June 2013

While most of the in vivo extracellular matrices are 3D, most of the in vitro cultures are 2D—where only ventral adhesion is permitted—thus modifying cell behavior as a way to self‐adaptation to this unnatural environment. We hypothesize that the excitation of dorsal receptors in cells already attached on a 2D surface (sandwich culture) could cover the gap between 2D and 3D cell–material interactions and result in a more physiological cell behavior. In this study we investigate the role of dorsal stimulation on myoblast differentiation within different poly(L‐lactic acid) (PLLA) sandwich‐like microenvironments, including plain material and aligned fibers. Enhanced cell differentiation levels were found for cells cultured with dorsal fibronectin‐coated films. Seeking to understand the underlying mechanisms, experiments were carried out with (i) different types of dorsal stimuli (FN, albumin, FN after blocking the RGD integrin‐binding site and activating dorsal cell integrin receptors), (ii) in the presence of an inhibitor of cell contractility, and (iii) increasing the frequency of culture medium changes to assess the effect of paracrine factors. Furthermore, FAK and integrin expressions, determined by Western blotting, revealed differences between cell sandwiches and 2D controls. Results show a stimuli‐dependent response to dorsal excitation, proving that integrin outside‐in signaling is involved in the enhanced cell differentiation. Due to their easiness and versatility, these sandwich‐like systems are excellent candidates to get deeper insights into the study of 3D cell behavior and to direct cell fate within multilayer constructs. Biotechnol. Bioeng. 2013;110: 3048–3058. © 2013 Wiley Periodicals, Inc.
Proton‐Conducting Supramolecular Metallogels from the Lowest Molecular Weight Assembler Ligand: A Quote for Simplicity
Authors: Saha Subhadeep , Schön Eva‐Maria , Cativiela Carlos , Díaz Díaz David , Banerjee Rahul
Published: June 2013

Oxalic acid has been proven to be the lowest molecular weight organic ligand able to form robust supramolecular metallogel networks in the presence of metal salts. In particular, two novel multifunctional metallogels were readily prepared at room temperature by simple mixing of stock solutions of CuII acetate monohydrate or CuII perchlorate hexahydrate and oxalic acid dihydrate. Formation of different polymorphs and unprecedented proton conduction under anhydrous conditions were also demonstrated with some of these materials.
Short‐term Effect of Verapamil on Coronary No‐Reflow Associated With Percutaneous Coronary Intervention in Patients With Acute Coronary Syndrome: A Systematic Review and Meta‐analysis of Randomized Controlled Trials
Authors: Su Qiang , Li Lang , Liu Yangchun
Published: June 2013

Background

To evaluate the clinical efficacy and safety of intracoronary verapamil injection in the prevention and treatment of coronary no‐reflow after percutaneous coronary intervention (PCI).

Hypothesis

Intracoronary verapamil injection may be beneficial in preventing no‐reflow/slow‐flow after PCI.

Methods

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials database. Randomized trials comparing the efficacy and safety of intracoronary verapamil infusion vs control in patients with acute coronary syndrome (ACS) were included. Meta‐analysis was performed by RevMan 5.0 software (Cochrane Collaboration, Copenhagen, Denmark) .

Results

Seven trials involving 539 patients were included in the analysis. Verapamil treatment was significantly more effective in decreasing the incidence of no‐reflow (risk ratio [RR]: 0.33; 95% confidence interval [CI]: 0.23 to 0.50) as well as reducing the corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) (weighted mean difference: −11.62; 95% CI: −16.04 to −7.21) and improving the TIMI myocardial perfusion grade (TMPG) (RR: 0.43; 95% CI: 0.29 to 0.64). Verapamil also reduced the 30‐day wall motion index (WMI) compared to the control. Moreover, the procedure reduced the incidence of major adverse cardiac events (MACEs) in ACS patients during hospitalization (RR: 0.37; 95% CI: 0.17 to 0.80) and 2 months after PCI (RR: 0.56; 95% CI: 0.33 to 0.95). However, administration of verapamil did not provide an additional improvement of left ventricular ejection fraction regardless of the time that had passed post‐PCI.

Conclusions

Intracoronary verapamil injection is beneficial in preventing no‐reflow/slow‐flow, reducing CTFC, improving TMPG, and lowering WMI. It is also likely to reduce the 2‐month MACEs in ACS patients post‐PCI.
Effects of Plant and Water Level on Nitrogen Variation in Overlying and Pore Water of Agricultural Drainage Ditches in Sanjiang Plain, Northeast China
Authors: Zhang Yan , Zhu Hui , Yan Baixing , Li Xuhui , Ou Yang
Published: June 2013

Agricultural drainage ditches are common as temporary storages of drainage water and may improve mitigation capacity of pollutants in Sanjiang Plain. Few ditch management practices have been proposed to alleviate nitrogen loads transported to downstream aquatic systems in this area. This study examined the nitrogen variation in overlying and pore water of a planted and natural drainage ditch of equal size and shape, as well as the low and high water levels of a planted drainage ditch in Sanjiang Plain. Results indicated that longer retention time was in favor of nitrogen removal in overlying water, especially for ammonium nitrogen (NH4‐N); high water level undermined nitrogen removal; there was no significant difference with retention time between the planted drainage ditch and the natural drainage ditch. Conversely, NH4‐N and nitrate nitrogen (NO3‐N) concentrations in pore water were lower in the planted ditch and high water level planted ditch than in the natural ditch. At present, farmers and managers keep drainage ditches nearly full of water to expediently irrigate, which may increase pollutant load in downstream receiving systems. Thus, our study is helpful in guidance for pollution control of agricultural nonpoint source in Sanjiang Plain.
Methods, Mechanisms and Typical Bio‐Indicators of Engineered Nanoparticle Ecotoxicology: An Overview
Authors: Zhuang Wen , Gao Xuelu
Published: June 2013

As nanotechnology industries increase production, increased release of engineered nanoparticles (NPs) to aquatic environments suggests a rising need for monitoring and evaluation of their potential toxicity. Based on previous and latest research results in the related field, this paper reviews methods, mechanisms, and typical bio‐indicators of nanomaterials ecotoxicological research. It outlines detecting methods of NPs in ecotoxicologial studies, and discusses suspension methods of nanoparticles in this field. Proteomics and genomics technologies are predicted to be indispensable means in ecotoxicological studies of NPs. It also points out that biology of particle‐induced oxidative stress is an important mechanistic paradigm, and so are solvent effects and the effects of NPs on other substances. Typical bio‐indicators in aquatic systems are claimed to be determined to avoid unnecessary animal testing whenever possible and to reduce unnecessary testing costs. In ecotoxicological research of NPs, fish species are generally considered as preferred species; for nanoparticle ecotoxicity, suspension‐feeding invertebrates may be a unique target group, therefore invertebrate testing is also very important; because of sensitivity to pollutants, phytoplankton testing should be strengthened. This paper also summarizes some conflicting results in current experiments, and gives some possible explanations. Finally, future research directions are proposed.
Reconstructing shifts in vital rates driven by long‐term environmental change: a new demographic method based on readily available data
Authors: González Edgar J. , Martorell Carlos
Published: June 2013

Frequently, vital rates are driven by directional, long‐term environmental changes. Many of these are of great importance, such as land degradation, climate change, and succession. Traditional demographic methods assume a constant or stationary environment, and thus are inappropriate to analyze populations subject to these changes. They also require repeat surveys of the individuals as change unfolds. Methods for reconstructing such lengthy processes are needed. We present a model that, based on a time series of population size structures and densities, reconstructs the impact of directional environmental changes on vital rates. The model uses integral projection models and maximum likelihood to identify the rates that best reconstructs the time series. The procedure was validated with artificial and real data. The former involved simulated species with widely different demographic behaviors. The latter used a chronosequence of populations of an endangered cactus subject to increasing anthropogenic disturbance. In our simulations, the vital rates and their change were always reconstructed accurately. Nevertheless, the model frequently produced alternative results. The use of coarse knowledge of the species' biology (whether vital rates increase or decrease with size or their plausible values) allowed the correct rates to be identified with a 90% success rate. With real data, the model correctly reconstructed the effects of disturbance on vital rates. These effects were previously known from two populations for which demographic data were available. Our procedure seems robust, as the data violated several of the model's assumptions. Thus, time series of size structures and densities contain the necessary information to reconstruct changing vital rates. However, additional biological knowledge may be required to provide reliable results. Because time series of size structures and densities are available for many species or can be rapidly generated, our model can contribute to understand populations that face highly pressing environmental problems.
Kinetic and Thermodynamic Investigations of CO2 Insertion Reactions into Ru–Me and Ru–H Bonds – An Experimental and Computational Study
Authors: Darensbourg Donald J. , Kyran Samuel J. , Yeung Andrew D. , Bengali Ashfaq A.
Published: June 2013

The rates of CO2 insertion into trans‐Ru(dmpe)2(Me)H [1, dmpe = 1,2‐bis(dimethylphosphino)ethane] and trans‐Ru(dmpe)2(Me)2 (2) derivatives were monitored by in situ infrared and 1H NMR spectroscopy. The reactions are first order in both CO2 and metal complex concentrations, and CO2 insertion into the Ru–H bond of 1 occurs instantaneously at 0 °C. The reverse process, decarboxylation, was observed to occur readily at ambient temperature as revealed by 13CO2 exchange with subsequent CO2 insertion into the Ru–Me bond at higher temperatures. No further CO2 insertion into the Ru–H bond of the resulting acetate complex was observed. The activation barrier for CO2 insertion into the first Ru–Me bond of 2 was determined to have ΔH‡ and ΔS‡ values of 12.7 ± 0.6 kcal mol–1 and –31.9 ± 2.0 e.u., respectively, which are indicative of a highly ordered transition state. The rate of CO2 insertion into the second Ru–Me bond was two orders of magnitude slower at ambient temperature and resulted in the formation of trans‐Ru(dmpe)2(O2CMe)2. In general, the insertion of CO2 into the Ru–H or Ru–Me bonds of trans‐Ru(dmpe)2(X)R (R = H or Me) was disvavored in the presence of poorly electron‐donating X ligands. For example, the insertion of CO2 into the Ru–H bond of trans‐Ru(dmpe)2(Cl)H was not observed even under forcing conditions. Computational results were in excellent agreement with these observations and predict a significant enhancement in CO2 activity and resultant complex stability if dmpe is replaced with tetramethylethylenediamine (tmeda).
A Highly Regio‐ and Diastereoselective Phosphane‐Catalyzed [3+2] Annulation of Morita–Baylis–Hillman Carbonates with Cyclic N‐Acyl Ketimines
Authors: Yang Li‐Jun , Cai Hua , Nie Jing , Ma Jun‐An
Published: June 2013

A highly regio‐ and diastereoselective phosphane‐catalyzed [3+2] annulation of Morita–Baylis–Hillman (MBH) carbonates with cyclic N‐acyl‐substituted ketimines was developed. In the presence of the catalyst PBu3 (10 mol‐%), a series of N‐fused tricyclic products were obtained in excellent yields and diastereoselectivities under mild conditions. An example of a catalytic enantioselective annulation is also presented.
Error analysis of idealized nanopore sequencing
Authors: O'Donnell Christopher R. , Wang Hongyun , Dunbar William B.
Published: June 2013

This numerical study provides an error analysis of an idealized nanopore sequencing method in which ionic current measurements are used to sequence intact single‐stranded DNA in the pore, while an enzyme controls DNA motion. Examples of systematic channel errors when more than one nucleotide affects the current amplitude are detailed, which if present will persist regardless of coverage. Absent such errors, random errors associated with tracking through homopolymer regions are shown to necessitate reading known sequences (Escherichia coli K‐12) at least 140 times to achieve 99.99% accuracy (Q40). By exploiting the ability to reread each strand at each pore in an array, arbitrary positioning on an error rate versus throughput tradeoff curve is possible if systematic errors are absent, with throughput governed by the number of pores in the array and the enzyme turnover rate.