bluuebunny/crossref_metadata_2025 huggingface dataset:
A generic biogeochemical module for earth system models
Authors: Fang Y. , Huang M. , Liu C. , Li H.-Y. , Leung L. R.
Published: June 2013

Abstract. Physical and biogeochemical processes regulate soil carbon dynamics and CO2 flux to and from the atmosphere, influencing global climate changes. Integration of these processes into earth system models (e.g. community land models – CLM), however, currently faces three major challenges: (1) extensive efforts are required to modify modeling structures and to rewrite computer programs to incorporate new or updated processes as new knowledge is being generated, (2) computational cost is prohibitively expensive to simulate biogeochemical processes in land models due to large variations in the rates of biogeochemical processes, and (3) various mathematical representations of biogeochemical processes exist to incorporate different aspects of fundamental mechanisms, but systematic evaluation of the different mathematical representations is difficult, if not impossible. To address these challenges, we propose a new computational framework to easily incorporate physical and biogeochemical processes into land models. The new framework consists of a new biogeochemical module with a generic algorithm and reaction database so that new and updated processes can be incorporated into land models without the need to manually set up the ordinary differential equations to be solved numerically. The reaction database consists of processes of nutrient flow through the terrestrial ecosystems in plants, litter and soil. This framework facilitates effective comparison studies of biogeochemical cycles in an ecosystem using different conceptual models under the same land modeling framework. The approach was first implemented in CLM and benchmarked against simulations from the original CLM-CN code. A case study was then provided to demonstrate the advantages of using the new approach to incorporate a phosphorus cycle into the CLM model. To our knowledge, the phosphorus-incorporated CLM is a new model that can be used to simulate phosphorus limitation on the productivity of terrestrial ecosystems.
Simulating run-up on steep slopes with operational Boussinesq models; capabilities, spurious effects and instabilities
Authors: Løvholt F. , Lynett P. , Pedersen G.
Published: June 2013

Abstract. Tsunamis induced by rock slides plunging into fjords constitute a severe threat to local coastal communities. The rock slide impact may give rise to highly non-linear waves in the near field, and because the wave lengths are relatively short, frequency dispersion comes into play. Fjord systems are rugged with steep slopes, and modeling non-linear dispersive waves in this environment with simultaneous run-up is demanding. We have run an operational Boussinesq-type TVD (total variation diminishing) model using different run-up formulations. Two different tests are considered, inundation on steep slopes and propagation in a trapezoidal channel. In addition, a set of Lagrangian models serves as reference models. Demanding test cases with solitary waves with amplitudes ranging from 0.1 to 0.5 were applied, and slopes were ranging from 10 to 50°. Different run-up formulations yielded clearly different accuracy and stability, and only some provided similar accuracy as the reference models. The test cases revealed that the model was prone to instabilities for large non-linearity and fine resolution. Some of the instabilities were linked with false breaking during the first positive inundation, which was not observed for the reference models. None of the models were able to handle the bore forming during drawdown, however. The instabilities are linked to short-crested undulations on the grid scale, and appear on fine resolution during inundation. As a consequence, convergence was not always obtained. It is reason to believe that the instability may be a general problem for Boussinesq models in fjords.
Imperial Administration and Epigraphy: In Defence of Prosopography
Authors: ECK WERNER
Published: June 2013

Administration produces documents. In that respect Roman administration does not differ from its modem counterparts. An identifying mark of Roman administration is the libellous, submitted to the emperor or to an official by a petitioner-even when the petitioner presents himself in person before the emperor, as so many embassies and legates of cities did. All appointments to senatorial and equestrian offices were made in written form, by codicilli, letters of appointment, although we can be sure that governors of the great military commands, if setting out from Rome (or from the emperor's place of residence at the time) received their commission personally and orally from the emperor. However, all this material, with some unique exceptions outside Egypt (and a few other localities in the Roman Near East), has vanished completely. To reconstruct the working of Roman administration from what has survived is difficult and only in part possible; if we persist against the odds in trying to do so, we are bound to stumble continuously against the limits of the available evidence and of our knowledge alike. This chapter discusses the administrators and prosopographical material; and the contested existence of rules governing patterns of promotion.
La transformación del presente en la narrativa española contemporánea. Una propuesta: la generación Nocilla.
Authors: Ros Ferrer Violeta
Published: June 2013

Resumen: En el marco de la era de la información, algunas formas narrativas pueden ser pensadas como el síntoma literario de un cambio en las formas de producir y percibir la cultura. Desde esta perspectiva, se hace urgente el estudio de la influencia de la tecnología y los medios de comunicación en la evolución de ciertas tendencias de la narrativa en el contexto de la España de la primera década del siglo XXI. Este artículo propone la presentación y análisis de los efectos estéticos e ideológicos de la producción literaria de la generación Nocilla en este contexto, así como la reflexión en torno las circunstancias que pueden haber facilitado la aparición y consolidación de la propuesta narrativa de estos autores.Palabras Clave: Narrativa, posmodernidad, canon, generación Nocilla, cambio cultural.Abstract: Within the frame of the Information Age, certain kind of literary fiction could be understood as a synthom of the change happened in the ways of producing and perceiving culture. From this perspective, a study of the influence of technology and media in spanish 21st century fiction is needed. In these terms, this paper presents generación Nocilla's literary production and considers its ideological and aesthetic effects in this context. It also considers the circumstances that might have provided the consolidation of this particular literary agenda. Key Words: Narrative, postmodernism, canon, Nocilla generation, culture change.
Reflexividad y narratividad en Ricardo Piglia: de Macedonio a Fitzgerald
Authors: Torres Perdigón Andrea
Published: June 2013

Resumen: Este artículo analiza algunos rasgos de la narrativa reciente del argentino Ricardo Piglia con relación a las poéticas de Macedonio Fernández y del estadounidense Francis Scott Fitzgerald. La primera parte trabaja la relación conflictiva de Piglia con el llamado posmodernismo; la segunda parte explica el vínculo entre Piglia y Macedonio, a través de la poética de la autonomía de lo literario; la tercera parte aborda la relación con Fitzgerald, por medio de un análisis de sus respectivas búsquedas de formas narrativas, para concluir en una cuarta parte ciertos cambios dentro de la propia obra novelesca de Piglia. Palabras clave: Piglia, Fitzgerald, Macedonio, posmodernismo, narratividad, metaficción Abstract: This article analyses some of the traits of Ricardo Piglia’s recent narrative fiction by means of its relation to Macedonio Fernández and the American author Francis Scott Fitzgerald. The first part develops Piglia’s conflictual approach to the postmodern. The second part explains the bond between Piglia and Macedonio by showing how their poetics defend the idea of literature’s autonomy. The third part examines his relation to the oeuvre of Fitzgerald by analyzing their respective ways of conceiving narrative forms. The article concludes with a reading of some transformations within Piglia’s novelistic works.Key words: Piglia, Fitzgerald, Macedonio,   postmodernism, narrativity, metafiction.
Bailando con la destrucción. Sobre cultura común y música popular en la Transición Española (1977-1987)
Authors: Méndez Rubio Antonio
Published: June 2013

El artículo analiza desde una perspectiva crítica el legado musical de los años de la llamada Transición, poniendo el foco en las relaciones entre música y sociedad que tan poca consideración han tenido desde la crítica musical y la musicología, áreas desde las que se han realizado aproximaciones partiendo de una visión de la música como un ámbito estético autónomo más que como una práctica social. El artículo pone el acento en los espacios de conflicto generados por las prácticas musicales de la época y en las estrategias de borramiento de ese conflicto con las que se ha tratado de abordar, en los últimos años, el periodo y su escena musical.
“Vencida a veces, nunca prisionera”. Georgina Herrera y Belkis Ayón: una poética de la autorrepresentación
Authors: Falcón Montes Aída Elizabeth
Published: June 2013

Resumen: El objetivo de este artículo es analizar la representación de la mujer negra a través de la obra de la poetisa cubana Georgina Herrera y la grabadora Belkis Ayón, y el modo en que el discurso referido a su sexualidad, su raza y su género ha contribuido a formar el imaginario de la identidad nacional.Con el fin de articular el contexto histórico y social de la población negra en Cuba, establezco un breve itinerario que parte de mediados del siglo XX  hasta el denominado Periodo Especial en los años 90 del pasado siglo. El conocimiento de estas diferentes etapas es decisivo para entender la situación de la mujer negra en Cuba. En una segunda fase, abordo el proceso de autorrepresentación en Herrera y Ayón  mediante el análisis y la posterior comparación de sus producciones literarias y pictóricas respectivamente con el fin de desvelar las motivaciones que impulsan a ambas a elaborar un discurso poético que se sustenta en el legado ancestral africano. Como se verá, este estudio ofrece una visión de la problemática de la mujer negra desde una perspectiva feminista, cuyo tratamiento es abordado teniendo en cuenta su raza, su clase y su género. Palabras clave: autorrepresentación, identidad, mujer negra, discurso de resistencia, cuerpoAbstract: The goal of this article is to analyze the representation of the black woman in the work of the Cuban poet Georgina Herrera and the engraver Belkin Ayón, and the way their discourse about their sexuality, their race, and their genre has contributed towards the formation of a national identity. With the aim of articulating the historical and social context of Afro-Cubans, I establish a brief itinerary which begins in the mid 20th century and ends with the so called “Período Especial” in the 1990s. On a second phase, I address the process of self-representation in Herrera and Ayón through the analysis and subsequent comparison of their literary and pictorial works respectively.  My objective is to bring to light the motivations that lead both women to create a poetic discourse based on their ancestral African legacy. It will become apparent that this study offers a vision of the Afro-Cuban woman from a feminist perspective. My approach also takes their race, class, and genre into account. Key Words: self-representation, identity, Afro-Cuban woman, resistance discourse, body.
Métodos de diagnóstico da resposta inflamatória uterina em vacas
Authors: Esteves Thomé Helder , Martins de Oliveira Bruna Marcele , Paes de Arruda Rubens , De Fátima Guimarães Carina , Sussai Thomé Ana Carolina , De Carvalho Balieiro Júlio Cesar , Barbosa Fernandes Claudia , Carvalho Celeghini Eneiva Carla
Published: June 2013

Os métodos de diagnósticos para a reação inflamatória uterina em bovinos ainda são frequentemente discutidos. O diagnóstico da endometrite por palpação retal e observação de descarga vaginal é provavelmente a base para o tratamento da maioria das vacas no campo. A vaginoscopia é um método adicional à palpação retal para investigar infecções uterinas. O grande desafio que poderia trazer benefícios aos tratamentos e ao desempenho reprodutivo é a detecção de vacas que apresentam endometrite subclínica ou clínica sem manifestações ou descargas anormais. As amostras citológicas podem ser obtidas por biopsia uterina, por swabs de algodão, escova ginecológica ou por lavagem uterina. Técnicas que produzam células bem preservadas e representativas de uma grande superfície do útero, sem causar danos ao trato reprodutivo, são requeridas para um consistentee confiável resultado de citologia. Técnicas não invasivas, como a ultrassonografia, para a avaliação do ambiente uterino podem contribuir. Utilizando o modo-B é possível identificar presença de conteúdo líquido no lúmen uterino; por sua vez, o modo Doppler colorido pode ser utilizado para estudar a perfusão vascular do útero com comprometimento endometrial.
Boas práticas de gestão de risco corporativo: estudo de dez empresas
Authors: Ching Hong Yuh , Colombo Thalita Maricone
Published: June 2013

Vários fatores externos têm pressionado as empresas à adoção da  gestão de  risco corporativo.  Os  objetivos desse trabalho são: a) sumarizar os padrões de comportamento na adoção das práticas de gestão de  risco pelas empresas pesquisadas; b) fazer uma convergência entre as práticas presentes na literatura e as adotadas pelas empresas. Essa pesquisa é teórico-empírica quanto à sua natureza e com objetivo  descritivo. A abordagem adotada é qualitativa/quantitativa e o procedimento é estudo de caso múltiplo de dez empresas. Um questionário semiestruturado foi utilizado como método de coleta de dados. A fim de veri- ficar se existem padrões entre as práticas empregadas, dois critérios de divisão foram utilizados entre as empresas: pequeno e grande porte; nacionais e multinacionais. Todas as empresas de pequeno porte são     do enfoque tradicional. O mesmo ocorre com todas as empresas nacionais. Além disso, todas as empresas   de enfoque tradicional, exceto uma, adotam todas as sete práticas de gestão de risco encontradas na lite- ratura. Entre as práticas, apenas uma – Independência entre Board e CEO – é adotada por todas as dez em- presas. Várias práticas foram citadas pelas empresas e não encontradas na literatura. A contribuição desse artigo é desenvolver uma estrutura conceitual de gestão de risco corporativo abrangendo o ciclo de gestão   de risco corporativo, seus resultados e  ferramentas que  levam  às  boas práticas. Uma convergência entre as práticas da literatura e  as  práticas adotadas pelas empresas é  apresentada como um  aperfeiçoamento  da estrutura conceitual. Como pesquisa futura, sugere-se repetir essa pesquisa em quantidade maior de empresas que a usada nesta pesquisa.
Origin of Phonon Glass–Electron Crystal Behavior in Thermoelectric Layered Cobaltate
Authors: Wu Lijun , Meng Qingping , Jooss Christian , Zheng Jin‐Cheng , Inada H. , Su Dong , Li Qiang , Zhu Yimei
Published: June 2013

Measurement of local disorder and lattice vibrations is of great importance for understanding the mechanisms whereby thermoelectric materials efficiently convert heat to electricity. Attaining high thermoelectric power requires minimizing thermal conductivity while keeping electric conductivity high. This situation is achievable by enhancing phonon scattering through specific structural disorder (phonon glass) that also retains sufficient electron mobility (electron crystal). It is demonstrated that the quantitative acquisition of multiple annular‐dark‐field images via scanning transmission electron microscopy at different scattering‐angles simultaneously allows not only the separation but also the accurate determination of static and thermal atomic displacements in crystals. Applying the unique method to the layered thermoelectric material (Ca2CoO3)0.62CoO2 discloses the presence of large incommensurate displacive modulation and enhanced local vibration of atoms, largely confined within its Ca2CoO3 sublayers. Relating the refined disorder to ab initio calculations of scattering rates is a tremendeous challenge. Based on an approximate calculation of scattering rates, it is suggested that this well‐defined deterministic disorder engenders static displacement‐induced scattering and vibrational‐induced resonance scattering of phonons as the origin of the phonon glass. Concurrently, the crystalline CoO2 sublayers provide pathways for highly conducting electrons and large thermal voltages.
Bioactive Luminescent Transition‐Metal Complexes for Biomedical Applications
Authors: Ma Dik‐Lung , He Hong‐Zhang , Leung Ka‐Ho , Chan Daniel Shiu‐Hin , Leung Chung‐Hang
Published: June 2013

The serendipitous discovery of the anticancer drug cisplatin cemented medicinal inorganic chemistry as an independent discipline in the 1960s. Luminescent metal complexes have subsequently been widely applied for sensing, bio‐imaging, and in organic light‐emitting diode applications. Transition‐metal complexes possess a variety of advantages that make them suitable as therapeutics and as luminescent probes for biomolecules. It is thus highly desirable to develop new luminescent metal complexes that either interact with DNA through different binding modes or target alternative cellular machinery such as proteins as well as to provide a more effective means of monitoring disease progression. In this Review, we highlight recent examples of biologically active luminescent metal complexes that can target and probe a specific biomolecule, and offer insights into the future potential of these compounds for the investigation and treatment of human diseases.
Preparation and evaluation of composite microspheres of polyacrylamide‐grafted polysaccharides
Authors: Tripathi Rahul , Mishra Brahmeshwar
Published: June 2013

The poor mechanical strength and instability of polysaccharide's gel takes away opportunities for versatile application. The grafting of polyacrylamide (PAM) onto polysaccharide was found to be an efficient tool for transforming its properties and obtaining stable and robust composite microspheres (CMs). In this study, free‐radical polymerization reaction was used for the grafting of PAM onto the polysaccharide backbone, and their hydrogel CMs were obtained through an ionotropic gelation method. Porous and buoyant CMs were obtained through the incorporation of sodium bicarbonate into the reaction mixture. Characterizations were done through Fourier transform infrared spectroscopy, thermal and scanning electron microscopy analysis. The mechanical strength and squeezing capacity were evaluated extensively through a modified syringe method developed in‐house. The squeezing capacity of grafted CMs diminished with the formation of a complex interpenetrating network. The Young's modulus, swelling kinetics, mechanical strength, and squeezing capacity of the grafted microspheres were compared extensively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2912–2922, 2013
Microstructural characteristics and crystallization behaviors of poly(l‐lactide) scaffolds by thermally induced phase separation
Authors: He Liumin , Zuo Qinhua , Shi Yunfeng , Xue Wei
Published: June 2013

In this study, poly(l‐lactic acid) (PLLA) was prepared by four typical approach systems, namely, solid–liquid phase‐separation processes from PLLA–dioxane at −80°C, PLLA–dioxane–water at −80°C, PLLA–tetrahydrofuran (THF) at −80°C, and PLLA–THF at 18°C. The microstructural characteristics and crystallization behaviors of PLLA were investigated by scanning electron microscopy, differential scanning calorimetry, X‐ray diffraction, and Fourier transform infrared spectroscopy. In the PLLA–dioxane binary system and PLLA–dioxane–water ternary system, the solvent froze immediately after quenching to a low temperature, and this restricted the PLLA chain arrangement. Thus, the PLLA amorphous phase dominated in the scaffolds, and solid‐walled structures were produced. THF was liquid throughout the entire process, which enabled free PLLA chain arrangement and further crystallization. Single crystals aggregated by crystal nucleation and growth at a critical temperature (Tc) of 18°C; this resulted in its most common and stable polymorph, the α form. However, α′‐form crystals, which were assumed to be limit‐disordered crystals of the α form, were produced at a low Tc (−80°C). Scaffolds with a plateletlike structure were produced at a Tc of 18°C, whereas a nanofibrous network was obtained at −80°C. PLLA crystallization competed with phase separation; thus, the crystal structure and scaffold morphology depended on the codevelopment of these two processes. Finally, the effects of the scaffold morphologies on the cell behaviors were studied, and the nanofibrous scaffold was found to have better cell adhesion and viability than the other three scaffolds. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39436.
Immobilization of β‐galactosidase from Escherichia coli onto modified natural silk fibers
Authors: Monier M.
Published: June 2013

A polymeric support based on the natural silk fibers was prepared and characterized for covalent immobilization of β‐galactosidase from Escherichia coli. The silk fibers were grafted using polyacrylonitrile in presence of benzophenone as a photo‐initiator. The grafted fibers were then activated by treatment with hydrazine hydrate followed by glyoxal cross‐linker. FTIR spectra, scanning electron microscope (SEM) in addition to the staining test derived from the Coomassie protein assay were utilized for investigation of the modification and immobilization steps. Also, the activity of both free and immobilized β‐galactosidase was evaluated as a function of the various important parameters like grafting percentage, pH, and temperature. In addition, the kinetic parameters Km and vmax for both free and immobilized enzyme were anticipated using Michaelis–Menten equation. The results in this study indicated that the prepared modified woven silk fibers could be used effectively as a polymeric support for immobilization of β‐galactosidase. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2923–2931, 2013
Permeability and transport model of epoxy membranes with various surface morphologies
Authors: Luo Yu‐Shun , Cheng Kuo‐Chung , Wang Chiu‐Ya , Chang Yi‐Min , Wu Ying‐Hong , Chen Yi‐Ping
Published: June 2013

Epoxy membranes that have interconnected pores with different surface structures were synthesized using the chemically induced phase separation process. The epoxy membrane was produced from a mixture of epoxy resin, D.E.R. 331, and the curing agent, 2,4,6‐tris‐(dimethylaminomethyl) phenol (DMP‐30) in diisobutyl ketone, while covered with a contacting film. It was found that the surface morphology of the epoxy membranes could be changed by the fraction of DIBK, or by using different contacting films of which the surface pore sizes ranged from 0.15 through 2.4 μm. Furthermore, ethanol permeabilities through the epoxy membranes were measured. The permeabilities are approximately 3–4700 L/m2 h bar and depend on either the bulk morphology or the skin structure of the membranes. The epoxy membranes with various porosities and ethanol permeabilities could be also prepared using different compositions of the DMP‐30 and diethylene triamine (DETA)) mixture. A modified Hagen–Poiseuille equation was proposed to describe the effects of the surface and bulk porosity on ethanol permeability. It was found that at low permeabilities, most of the resistance of the surface layers is higher than that of the bulk section. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2938–2946, 2013
Targeted functionalization of spruce O‐acetyl galactoglucomannans—2,2,6,6‐tetramethylpiperidin‐1‐oxyl‐oxidation and carbodiimide‐mediated amidation
Authors: Leppänen Ann‐Sofie , Xu Chunlin , Eklund Patrik , Lucenius Jessica , Österberg Monika , Willför Stefan
Published: June 2013

Modified spruce O‐acetyl galactoglucomannans (GGMs) can be used as molecular anchors to alter the surface properties or to activate the surface of cellulose. To selectively introduce functionalities, GGMs were oxidized on C‐6 of hexoses by 2,2,6,6‐tetramethylpiperidin‐1‐oxyl‐mediated oxidation. Different degrees of oxidation were successfully obtained by varying the reaction parameters. Low degrees could be obtained by performing the oxidations in bromide‐free conditions. The formed uronic acids were further modified by a carbodiimide‐mediated amidation reaction, which opens a window for introducing various functionalities selectively on hexoses. The adsorption of the modified GGMs to various cellulose samples was investigated. Indirect bulk sorption to fibers was compared to direct adsorption to nanofibrillated cellulose ultrathin films. GGMs with low degrees of oxidation showed high affinity to cellulose surfaces and could be sorbed onto cellulose in pure water. Moderate amounts of GGMs with high degree of oxidation could be sorbed onto cellulose in the presence of salts. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3122–3129, 2013
Preparation, characterization of UV‐Curable Waterborne Polyurethane‐Acrylate and the application in metal iron surface protection
Authors: Xu Jicheng , Rong Xinshan , Chi Tongyao , Wang Ming , Wang Yingying , Yang Dongya , Qiu Fengxian
Published: June 2013

Hydroxyethyl methyl acrylate (HEMA) capped waterborne polyurethane‐acrylate (WPUA) oligomer was firstly prepared from isophorone diisocyanate (IPDI), polyether polyol (NJ‐220), dimethylolbutanoic acid (DMBA), HEMA via in‐situ and anionic self‐emulsifying method. Ultraviolet (UV) curable WPUA coating was obtained from HEMA‐capped oligomer, butyl acrylate (BA) and multifunctional acrylates (TPGDA) as reactive diluents, and Darocur 1173 as photoinitiator. The physical properties of WPUA oligomers, such as particle size, apparent viscosity, and surface tension were investigated. Some mechanical properties of UV‐WPUA films, such as contact angles, thermal properties, and solvent (water, HCl, NaOH, NaCl, and ethanol) resistance of UV‐WPUA coating films were measured. The surface morphologies were measured by scanning electron microscope and atomic force microscope. The surface free energy of the UV‐cured film was calculated from contact angle measurements using the Lewis acid–base three liquids method. The specific UV‐WPUA coating was selected to protect the iron materials that observed the effect of the protection. The results indicate that the prepared UV‐WPUA coating has excellent protective behavior to metal iron materials and may offer some contributions to protect iron cultural relics. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3142–3152, 2013
Transparent, flexible, and high‐strength regenerated cellulose/saponite nanocomposite films with high gas barrier properties
Authors: Yang Quanling , Saito Tsuguyuki , Isogai Akira
Published: June 2013

Regenerated cellulose‐saponite nanocomposite films were prepared from LiOH/urea solutions, and exhibited high optical transparency and flexibility. The saponite platelets formed intercalated nanolayered structures in the composites. The longitudinal directions of both the cellulose II crystallites and the saponite platelets were preferentially oriented parallel to the film surface in the composites. The good nanodispersibility and high orientation of the saponite platelets in the composite films resulted in high mechanical strength, high Young's modulus, and good thermal dimensional stabilities, and gas barrier properties in the composites, compared with a reference cellulose film. Moreover, the tensile strength and Young's modulus of the composite film reached 241 MPa and 7.7 GPa, respectively, when a simple drawing process was applied to the wet composite film; this is probably owing to the improvement in the orientation of the cellulose II crystallites and saponite platelets in the composites. The composite films also showed high toughness and ductility. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3168–3174, 2013
Real‐time user interest modeling for real‐time ranking
Authors: Liu Xiaozhong , Turtle Howard
Published: June 2013

User interest as a very dynamic information need is often ignored in most existing information retrieval systems. In this research, we present the results of experiments designed to evaluate the performance of a real‐time interest model (RIM) that attempts to identify the dynamic and changing query level interests regarding social media outputs. Unlike most existing ranking methods, our ranking approach targets calculation of the probability that user interest in the content of the document is subject to very dynamic user interest change. We describe 2 formulations of the model (real‐time interest vector space and real‐time interest language model) stemming from classical relevance ranking methods and develop a novel methodology for evaluating the performance of RIM using Amazon Mechanical Turk to collect (interest‐based) relevance judgments on a daily basis. Our results show that the model usually, although not always, performs better than baseline results obtained from commercial web search engines. We identify factors that affect RIM performance and outline plans for future research.
Phenyl‐1,3,5‐Trithienyl‐Diketopyrrolopyrrole: A Molecular Backbone Potentially Affording High Efficiency for Solution‐Processed Small‐Molecule Organic Solar Cells through Judicious Molecular Design
Authors: Zhang Shanlin , Jiang Bo , Zhan Chuanlang , Huang Jianhua , Zhang Xin , Jia Hui , Tang Ailing , Chen Lili , Yao Jiannian
Published: June 2013

Finding new molecular backbones is necessary for further advances in solution‐processed small‐molecule organic solar cells (SM‐OSCs). Increasing molecular π conjugation generally enhances the light‐harvesting ability, and the resulting strong π–π‐stacking interactions improve the charge‐carrier transport ability; both increase the efficiency. In this study, we focus on the phenyl‐1,3,5‐trithienyl (3T‐P) backbone because of its C3 symmetry, planarity, and particularly high conjugation between the three arms through the core phenyl unit. When the three arms were functionalized with diketopyrrolopyrrole (DPP) units to afford 3D-T-P, only modest efficiency was achieved (1.16 %). Introduction of 4,8‐bis(2‐(2‐ethylhexylthienyl)) benzodithiophene (BDT) between the 3T‐P and DPP units to give 3D-B-T-P enhanced the light‐harvesting ability, and particularly improved the hole mobility by 1.5 orders of magnitude (5.91×10−2 versus 1.05×10−3 cm2 V−1 s−1). When using PC71BM as the acceptor material, 3D-B-T-P gave the best power conversion efficiency (PCE) of 2.27 %, which is about 1.9 times higher than the best efficiency from 3D-T-P (≈1.16 %). The efficiency can be improved up to 3.60 % with 3 % (v/v) of 1,8‐diiodooctane (DIO) as the cosolvent and thermal annealing at 100 °C for 10 min. This PCE is, to the best of our knowledge, the highest efficiency reported to date among the phenyl‐1,3,5‐based C3‐symmetric molecules. Removing one DPP unit from 3D-T-P to form 2D-T-P, or from 3D-B-T-P to form 2D-B-T-P both decreased the light‐harvesting ability and the hole mobility, thereby affording lower efficiency. Taken together, our results demonstrate that the planar phenyl‐1,3,5‐trithienyl‐based C3‐symmetric structure can be a promising backbone, and enhancing the conjugation of the 3D-T-P backbone can effectively improve the device performance.
Case of cephalothoracopagus conjoined twinning in an embryonic mouse
Authors: Hynd Thomas E. , Buckley Cadie L. , Lozanoff Scott
Published: June 2013

BACKGROUND

Cephalothoracopagus twinning is extremely rare, and it is characterized by fusion of the head and thorax, two separate spines, pelves, and fore‐ and hindlimbs. CASE: In this case study, we describe cephalothoracopagus twinning in an embryonic mouse displaying a large but exencephalic head, median facial cleft, a single eye, and a second hindbrain rotated roughly 90° from a second spinal cord. There is a bony connection joining the clavicles, resulting in merged asternal thoracic cavities containing two hearts and four lungs. The abdominal cavities contain double caudal digestive tract structures, but a single esophagus and stomach.

CONCLUSION

There are several proposed theories regarding the mechanism of spontaneous conjoined twinning; however, the specific mechanisms are still largely unknown. In this report, we highlight the morphological features in a murine example of cephalothoracopagus twinning, furthering our understanding of this rare occurrence while also demonstrating developmental morphogenesis consistent with that reported for human conjoined twins. Birth Defects Research (Part A) 97:421–424, 2013. © 2013 Wiley Periodicals, Inc.
Association between PTCH1 polymorphisms and risk of neural tube defects in a Chinese population
Authors: Wang Zhen , Wang Li , Shangguan Shaofang , Lu Xiaolin , Chang Shaoyan , Wang Jianhua , Zou Jizhen , Wu Lihua , Zhang Ting , Luo Yi
Published: June 2013

BACKGROUND

SHH signaling pathway plays an important role in the formation of the neural plate and is involved in the regulation of the dorsoventral (DV) axis of the neural tube. Some neural tube defects (NTDs) may be caused through overactivation of the SHH signaling pathway. The PTCH1 gene, encoding a negative regulator of SHH signaling, affects neural tube closure in animal models. However, in humans, the relationship between single nucleotide polymorphisms (SNPs) of the PTCH1 gene and neural tube defects remains unclear.

METHODS

MassARRAY®GENOTYPER™ was used to genotype 18 SNPs of the PTCH1 gene in 187 NTDs and 212 control samples, to determine whether PTCH1 polymorphisms are related to NTDs. MassARRAY®EpiTYPER™ was performed to assess whether methylation modifications may be associated with SNP genotypes in this Chinese population.

RESULT

Increased risk for spina bifida was observed with the G allele of c.3944C>T and the T allele of c.1729™2350G>A in female patients when compared to the normal control group. High methylation levels were detected in those controls bearing the G allele of c.3944C>T.

Conclusion

In summary, polymorphisms of the PTCH1 gene may be genetic predisposing factors for spina bifida in the population studied. In addition, methylation modifications associated with the c.3944C>T polymorphism, may provide protection. Birth Defects Research (Part A) 97:409–415, 2013. © 2013 Wiley Periodicals, Inc.
Photoinduced oxidation of a tris(2,2'‐bipyridyl)ruthenium(II)–peroxodisulfate chemiluminescence system for the analysis of mebeverine HCl pharmaceutical formulations and biological fluids using a two‐chip device
Authors: Lawati Haider A. J. Al , Dahmani Zeiyana M. Al , Varma Gouri B , Suliman FakhrEldin O
Published: June 2013

A new method for the analysis of mebeverine hydrochloride (MEB) has been developed using a two‐chip device. The method is highly selective, sensitive, rapid and consumes minute amount of reagents. The developed method is free of interference from the degradation products of MEB and from common ingredients present in pharmaceutical formulations. The limit of detection was 0.043 µg/mL, and the limit of quantification was 0.138 µg/mL. The short analysis time per sample (20 s) allowed a large number of analyses to be performed within a very short time. Various samples were analyzed, including two different pharmaceutical formulations and a uniformity of content analysis for 20 tablets from a known batch and two biological samples at different concentrations. In addition, the method was compared with a validated high‐performance liquid chromatography (HPLC) method and the results clearly indicated the suitability of the developed method for routine analyses. A new mechanism for the tris(2,2'‐bipyridyl)ruthenium(II) (Ru(bpy)32+)‐peroxodisulfate (S2O82−) chemiluminescence (CL) system has also been proposed. The mechanism is based on photoinduced oxidation of Ru(bpy)32+ to Ru(bpy)33+ via the formation of Ru(bpy)32+* upon irradiation with visible light. S2O82− then oxidizes Ru(bpy)32+* to Ru(bpy)33+ and the analyte subsequently reduces the resultant Ru(bpy)33+ to Ru(bpy)32+*, which then produces the CL signal. Copyright © 2013 John Wiley & Sons, Ltd.
Physical chemistry of nucleic acids and their complexes
Authors: Ghirlando Rodolfo , Felsenfeld Gary
Published: June 2013

Studies of the physical properties of nucleic acids began almost immediately following the discovery of the DNA structure. Early investigations focused on the stability and specificity of multi‐strand polynucleotide complexes, then gradually on their interaction with other molecules, particularly proteins. As molecular and structural biology expanded to provide detailed information about biochemical mechanisms, physical studies eventually acquired the additional constraint that they should be relevant to functioning biological systems. We describe work in our laboratory that began with investigations of relatively simple questions about the role of electrostatic interactions in the stabilization of multi‐strand nucleic acid structures, and evolved to studies of chromatin structure in vitro and within the nucleus. Published 2013 Wiley Periodicals, Inc*. Biopolymers 99: 910–915, 2013.
Mucin‐Type Glycopeptide Structure in Solution: Past, Present, and Future
Authors: Barchi Joseph J.
Published: June 2013

Mucins are very high molecular weight glycoproteins that form a “mucus” barrier at the surface of epithelial cells. They are heavily glycosylated with O‐linked glycans that are involved in myriad cellular functions, including protection from external changes in pH, ion flux and reactive oxygen species. Aberrations in mucin expression and their glycan constitution have been associated with many disease states including gastritis, pulmonary disorders and cancer. High resolution structural information on mucins is lacking due to their complexity, in particular their large size and the many variants of O‐linked glycans produced in their biosynthesis. This review discusses the structures of glycopeptides that contain “mucin‐type” glycosylation, and concentrates primarily on data obtained by NMR spectroscopy. The effect of the glycan on the peptide backbone, the features that have shown to be common to this type of glycosylation and the differences of glycosylation at serine and threonine residues are the major topics of discussion. Published 2013 Wiley Periodicals, Inc. Biopolymers 99: 713–723, 2013.
Rearranging RNA structures at 75°C? toward the molecular mechanism and physiological function of the thermus thermophilus DEAD‐box helicase hera
Authors: Klostermeier Dagmar
Published: June 2013

DEAD‐box helicases catalyze the ATP‐dependent destabilization of RNA duplexes. Hera is a DEAD‐box helicase from Thermus thermophilus that consists of a helicase core, followed by a C‐terminal extension comprising a dimerization domain and an RNA‐binding domain. The combined structural information on individual Hera domains provides a molecular model of the Hera dimer. The modular architecture with flexible connections between individual domains affords different relative orientations of the RBD relative to the Hera helicase core, and of the two helicase cores within the dimer. Presumably, domain movements are intimately linked to RNA binding, to the interplay of the RBD and the helicase core, and to RNA unwinding, and may impact on the functional cooperation of the two helicase cores in RNA unwinding. The in vivo function of Hera is unknown. The Hera RBD recognizes two distinct elements in the RNA substrate, a single‐stranded and a structured region. The helicase core then unwinds an adjacent RNA duplex in an ATP‐dependent reaction. Overall, this mode of action is reminiscent of DEAD‐box proteins that act as general RNA chaperones. This review summarizes the current knowledge on Hera structure and function, and discusses a possible role of Hera in the Thermus thermophilus cold‐shock response. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 1137–1146, 2013.
Profiling and identification of the absorbed constituents and metabolites of schisandra lignans by ultra‐performance liquid chromatography coupled to mass spectrometry
Authors: Sun Hui , Wu Fangfang , Zhang Aihua , Wei Wenfeng , Han Ying , Wang Xijun
Published: June 2013

Schisandra chinensis Baill grows wild in Russia, China, Korea and Japan, and its fruit has been found to be effective in amnesia and insomnia. It is enriched in schisandra lignans (SL) that are major components responsible for therapeutic action. However, there are no reports on the biotransformation analysis of SL. An ultra‐performance liquid chromatography/electrospray‐ionization high‐definition mass spectrometry (UPLC‐Q‐TOF‐HDMS) method was developed to investigate the metabolism of SL in vivo. MS was performed on a Waters Micromass high‐definition system with an electrospray ionization source in positive ion mode and automated MetaboLynx software analysis with excellent MS accuracy and enhanced MS data acquisition. An improved mass defect filter (MDF) method employing both drug and core structure filter templates was applied to the processing of UPLC‐Q‐TOF‐HDMS data for the detection and structural characterization of metabolites. In this study, 30 metabolites were detected and identified in vivo, and demethylation and hydroxylation were confirmed as the primacy metabolic pathway for SL in rat plasma. In conclusion, the presently developed methodology was suitable for biotransformation research of SL and will find wide use in metabolic studies for other herbal medicines. Copyright © 2013 John Wiley & Sons, Ltd.
Sheathless transcatheter aortic valve implantation via the direct aortic approach
Authors: Antonis Paul , Gooley Robert , Moshinsky Randall , Meredith Ian T.
Published: June 2013

Transcatheter aortic valve replacement (TAVR) has become an accepted alternate treatment modality to surgical aortic valve replacement in high surgical risk patients. There remains, however, a subset of patients in whom safe delivery of a TAVR device cannot be achieved by the femoral or subclavian routes. In such cases the direct aortic or transapical routes can be used though this still requires suitable anatomy. We present the first reported case of a direct aortic TAVR using a sheathless technique in order to provide sufficient distance to safely deliver the prosthesis. © 2013 Wiley Periodicals, Inc.
Functional and morphological assessment of side branch after left main coronary artery bifurcation stenting with cross‐over technique
Authors: Kang Soo‐Jin , Ahn Jung‐Min , Kim Won‐Jang , Lee Jong‐Young , Park Duk‐Woo , Lee Seung‐Whan , Kim Young‐Hak , Lee Cheol Whan , Park Seong‐Wook , Park Seung‐Jung
Published: June 2013

Background

In left main coronary artery (LMCA) bifurcation lesions, hemodynamic and geometrical change in left circumflex artery (LCX) ostium after main branch (MB) stenting has not been known. This study evaluated how accurately intravascular ultrasound (IVUS) predicts the functional compromise of the sidebranch.

Methods

A single‐stent cross‐over technique was used to treat LMCA bifurcation lesions in 43 patients with LCX ostial diameter stenosis (DS) of <50%. The fractional flow reserve (FFR) in the LCX was measured after MB stenting, MB and sidebranch pullback IVUS was performed prestenting and poststenting.

Results

After MB stenting, angiographic DS >50% at the LCX ostium was observed in 18 (42%) patients, while only 3 (7%) showed FFR <0.80. A pre‐procedural minimal lumen area (MLA) of <3.7 mm2 within the LCX ostium was predictive of a poststenting FFR <0.80, with a sensitivity of 100%, specificity of 71%, a positive predictive value (PPV) of 16%, and a negative predictive value (NPV) of 100% (area under curve 0.80, P < 0.001). Moreover, pre‐procedural plaque burden of >56% at the LCX ostium predicted FFR <0.80, with a sensitivity of 100%, specificity of 65%, a PPV of 14%, and a NPV of 100% (area under curve 0.80, P < 0.001). A poststenting LCX ostial DS >57% predicted FFR <0.80 with a sensitivity of 100%, specificity of 88%, a PPV of 38% and a NPV of 100% (area under curve 0.962, P < 0.001). However, the poststenting MLA within the LCX ostium showed no significant correlation with FFR (r = 0.197, P = 0.391).

Conclusions

In LMCA bifurcation lesions with mild LCX ostial disease, the use of single‐stent technique rarely resulted in the functional LCX compromise. Because the functional LCX stenosis is poorly predicted by a small MLA, sidebranch treatment should be based on the poststenting FFR. © 2013 Wiley Periodicals, Inc.
Pediatric patient radiation dosage during endomyocardial biopsies and right heart catheterization using a standard “ALARA” radiation reduction protocol in the modern fluoroscopic Era
Authors: Sutton Nicole J. , Lamour Jacqueline , Gellis Laura A. , Pass Robert H.
Published: June 2013

Background

Surveillance endomyocardial biopsy (EMB) with right heart catheterization (RHC) is the standard of care for the assessment of post cardiac transplantation rejection. This procedure has traditionally relied upon fluoroscopy, which exposes both patient and staff to the risks of ionizing radiation. These risks may be of particular concern in the transplant patient who must undergo many such procedures lifelong. We present data on a new “ALARA – As Low As Reasonably Achievable” protocol to reduce radiation exposure during the performance of RHC with EMB.

Methods

All cardiac transplantation patients < 21 years of age who underwent RHC with EMB at The Children's Hospital at Montefiore from 6/11–12/11 were included. EMB was performed after all right heart pressures including wedge pressure and thermodilution cardiac output were measured. A novel ALARA protocol consisting of multiple features including ultra‐low frame rates (2–3 fps), low fluoro dose/frame (10–18 nGy/frame), use of the “air‐gap” technique for patients < 20 kg, and multiple other techniques aimed at minimizing use of fluoroscopy were employed in all cases. Demographics, procedural data and patient radiation exposure levels were collected and analyzed.

Results

18 patients underwent 45 surveillance RHC with EMB in the study period and were the subject of this analysis. The mean age was 5.9 ± 6.1 years, weight was 20.4 kg ± 16.6 kg, and BSA was 0.75 ± 45 m2. PA fluoroscopy was used exclusively in 45/45. Vascular access was RFV (21/45; 47%), RIJV (17/45; 38%), LFV (4/45; 9%) and LIJV (3/45; 7%). The median number of EMB specimens obtained was 5 (range, 4–7). The median fluoroscopy time was 3.7 min (range, 1.2–9). The median air Kerma product (K) was 1.4 mGy (range, 0.4–14), and dose area product (DAP) was 15.8 uGym2 (range, 3.5–144.5). The K and DAP are substantially lower than any prior published data for RHC/EMB in this patient group. There were no procedural complications.

Conclusions

The use of a novel ALARA protocol for RHC and EMB in pediatric cardiac transplantation patients markedly reduced radiation exposure to levels far below any previously reported values without negatively affecting the safety or efficacy of these procedures. © 2013 Wiley Periodicals, Inc.