Note: This page contains sample records for the topic madsa matriz para from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
1

Mensaje para alumnos y padres  

NASA Video Gallery

El astronauta de la NASA José Hernández alienta a los estudiantes a que sigan sus sueños. Hernández también habla acerca del papel que juegan los padres para ayudar a que sus hijos hagan realidad s...

2

Tomografía computarizada (TC) y exploraciones para cáncer  

Cancer.gov

Hoja informativa que describe el procedimiento y la tecnología de exploraciones con tomografía computarizada así como sus usos para el diagnóstico, para exámenes de detección y para tratamiento del cáncer.

3

Centro para la Salud Mundial del NCI  

Cancer.gov

El Centro para la Salud Mundial del NCI coordina actividades de investigación y trabaja con socios nacionales e internacionales para entender y enfrentar la carga que representa el cáncer a nivel mundial.

4

?-Cyclodextrin- para-aminosalicylic acid inclusion complexes  

NASA Astrophysics Data System (ADS)

Complex formation of ?-cyclodextrin with para-aminosalicylic acid in buffer solutions is studied by UV spectroscopy. It is found that the stoichiometric proportion of the components in the ?-cyclodextrin-para-aminosalicylic acid inclusion complex is 1:1. The Ketelar equation is used to calculate the stability constants of the inclusion complexes at different temperatures. The thermodynamic parameters of the complex formation process (?G, ?H, ?S) are calculated using the van't Hoff equation. The 1:1 ?-cyclodextrin-para-aminosalicylic acid inclusion complex is prepared in solid form and its characteristics are determined by IR spectroscopic and x-ray diffraction techniques.

Roik, N. V.; Belyakova, L. A.; Oranskaya, E. I.

2010-11-01

5

Preguntas para el doctor sobre el cáncer  

Cancer.gov

Serie de preguntas, organizadas por tema, que los pacientes con cáncer pueden hacerle al médico o a otros miembros de su equipo de atención médica para conocer más acerca de su tipo de cáncer y lo que pueden esperar.

6

Una técnica para filtrar patrones de fringing  

NASA Astrophysics Data System (ADS)

Se presenta una nueva técnica para filtrar los patrones de fringing producidos en los CCDs tipo RCA. El método consiste en construir un mapa con los ángulos de inclinación de las franjas en cada punto de la imagen. Este mapa es ulteriormente utilizado para alinear con el patrón de interferencia una ventana estrecha, sobre la que se aplica un filtro de mediana. Este procedimiento permite eliminar la mayor parte del ruido del patrón de fringing sin destruirlo.

Ostrov, P. G.

7

The ParaScope parallel programming environment  

NASA Technical Reports Server (NTRS)

The ParaScope parallel programming environment, developed to support scientific programming of shared-memory multiprocessors, includes a collection of tools that use global program analysis to help users develop and debug parallel programs. This paper focuses on ParaScope's compilation system, its parallel program editor, and its parallel debugging system. The compilation system extends the traditional single-procedure compiler by providing a mechanism for managing the compilation of complete programs. Thus, ParaScope can support both traditional single-procedure optimization and optimization across procedure boundaries. The ParaScope editor brings both compiler analysis and user expertise to bear on program parallelization. It assists the knowledgeable user by displaying and managing analysis and by providing a variety of interactive program transformations that are effective in exposing parallelism. The debugging system detects and reports timing-dependent errors, called data races, in execution of parallel programs. The system combines static analysis, program instrumentation, and run-time reporting to provide a mechanical system for isolating errors in parallel program executions. Finally, we describe a new project to extend ParaScope to support programming in FORTRAN D, a machine-independent parallel programming language intended for use with both distributed-memory and shared-memory parallel computers.

Cooper, Keith D.; Hall, Mary W.; Hood, Robert T.; Kennedy, Ken; Mckinley, Kathryn S.; Mellor-Crummey, John M.; Torczon, Linda; Warren, Scott K.

1993-01-01

8

MÉTODOS PARA DETERMINAÇÃO DA DENSIDADE BÁSICA DE CAVACOS PARA CONÍFERAS E FOLHOSAS  

Microsoft Academic Search

1 - INTRODUÇÃO A densidade da madeira é uma característica complexa resultante da combinação de diversos fatôres. Existem inúmeros trabalhos mostrando sua relação com as dimensões das fibras, particularmente espessura da parede, volume dos vasos e parênquimas, proporção entre madeira primaveril e outonal, e arranjo dos elementos anatômicos. Êste assunto tem sido intensivamente estudado para as coníferas, porém para as

Celso Edmundo; Bochetti Foelkel; Maria Aparecida Mourão Brasil; Luiz Ernesto; George Barrichelo

9

PRODUCTOS TUBULARES PARA REDUCIR EL COSTO TOTAL  

Microsoft Academic Search

Nuevos equipos, materiales, herramientas y operaciones se han desarrollado con el objetivo de reducir los tiempos de ejecución y\\/o de completación de los pozos y por lo tanto el costo operativo y de materiales. En este trabajo nos ocuparemos de mencionar algunos de los métodos y materiales alternativos para llevar a cabo estas operaciones, especialmente en los que están involucradas

Daniel Ghidina; Fabián Benedetto

10

Sistema de Web Mapping para Geologia Médica  

Microsoft Academic Search

Resumo - Este trabalho apresenta um sistema de Web Mapping para pesquisa em Geologia Médica, no qual, por meio de uma navegação em mapas interativos, epidemiologistas visualizam as distribuições espaciais de teores de elementos químicos em águas não tratadas (bacias hidrográficas) e dos coeficientes de morbi-mortalidade por doenças nos municípios. A sobreposição desses temas compõe um mapa onde se podem

Humberto Cereser Ibañez; Marilea Vieira de Camargo; Hélio Pedrini

11

Para-hydrogen perspectives in hyperpolarized NMR.  

PubMed

The first instance of para-hydrogen induced polarization (PHIP) in an NMR experiment was serendipitously observed in the 1980s while investigating a hydrogenation reaction (Seldler et al., 1983; Bowers and Weitekamp, 1986, 1987; Eisenschmid et al., 1987) [1-4]. Remarkably a theoretical investigation of the applicability of para-hydrogen as a hyperpolarization agent was being performed in the 1980's thereby quickly providing a theoretical basis for the PHIP-effect (Bowers and Weitekamp, 1986) [2]. The discovery of signal amplification by a non-hydrogenating interaction with para-hydrogen has recently extended the interest to exploit the PHIP effect, as it enables investigation of compounds without structural alteration while retaining the advantages of spectroscopy with hyperpolarized compounds [5]. In this article we will place more emphasis of the future applications of the method while only briefly discussing the efforts that have been made in the understanding of the phenomenon and the development of the method so far. PMID:23932399

Glöggler, Stefan; Colell, Johannes; Appelt, Stephan

2013-10-01

12

Planificación para la etapa final de la vida  

Cancer.gov

Información para pacientes, sus familiares y amigos sobre el cuidado del paciente terminal, la planificación para el final de la vida, y la aflicción, el duelo y manejo de la pérdida de un ser querido.

13

EVALUACIÓN ERGONÓMICA DEL USO DE BOMBAS PORTATILES PARA FUMIGAR  

Microsoft Academic Search

Como primera actividad se observó al operario trabajando, anotando cualquier detalle que fuera relevante para la investigación, posteriormente se evaluó con el método “e-RULA” el uso de las mochilas para fumigar cuando se encuentran con el liquido para fumigar y cuando se encuentran vacías. Adicionalmente se aplicaron encuestas a 30 empleados campesinos (hombres) que laboran en ranchos y tienen por

Karla CeliaVázquez Arroyo; Hugo Cesar Ramos Herrera; Dulce María García Gómez; Juan Luis Hernández Arellano

2007-01-01

14

The para radiation effects current simulator  

NASA Astrophysics Data System (ADS)

The Parametric Analysis of Radiation effects software development is given the general title PARA. This report describes the development of algorithms and source codes for the simulation of radiation effects on CMOS ICs. The project concentrated on the simulation of total dose effects and the ways to establish/predict the operational lifetime and radiation tolerance of ICs. The switch level simulator incorporates the capability to assign bias dependent post-irradiation drive parameters to transistors within a microcircuit and to calculate propagation delays based on those parameters. This permits test vectors to be assigned based on worst case post-irradiation propagation delays.

Bhuva, Bharat; Kerns, Sherra

1992-01-01

15

On q-DEFORMED Para Oscillators and PARA-q Oscillators  

NASA Astrophysics Data System (ADS)

Three generalized commutation relations for a single mode of the harmonic oscillator which contains para-bose and q oscillator commutation relations are constructed. These are shown to be inequivalent. The coherent states of the annihilation operator for these three cases are also constructed.

Kumari, M. Krishna; Shanta, P.; Chaturvedi, S.; Srinivasan, V.

16

Tributación Simplificada para Pequeñas y Microempresas: Análisis y Propuesta de Reforma para el Caso Chileno  

Microsoft Academic Search

Este trabajo analiza las principales debilidades de los actuales regímenes simplificados de tributación a la renta en Chile y propone un nuevo modelo para la tributación dirigido a la pequeña y microempresa (PYME). El diagnóstico indica que los actuales regímenes simplificados son, en general, efectivos en reducir los costos de cumplimiento. No obstante, detecta tres deficiencias que perjudican fuertemente su

Patricio Barra

2005-01-01

17

ParaView for climate scientists  

NASA Astrophysics Data System (ADS)

ParaView is an immensely popular scientific visualization framework that provides a variety of tools necessary for scientific visualization especially dealing with large data that ultimately leads to better understanding of simulation and non simulation data. The Ultrascale Visualization Climate Data Analysis Tools (UV-CDAT), is a powerful and complete front-end to a rich set of visual-data exploration and analysis capabilities well suited for climate-data analysis problems. This talk describes integration of Paraview within UV-CDAT framework by leveraging python interface of Paraview and various new features added to uvcdat and Paraview specifically targeting climate data such as new readers, filters and parallel spatiotemporal capabilities.

Chaudhary, A.

2012-12-01

18

On Lightlike Geometry of Para-Sasakian Manifolds  

PubMed Central

We study lightlike hypersurfaces of para-Sasakian manifolds tangent to the characteristic vector field. In particular, we define invariant lightlike hypersurfaces and screen semi-invariant lightlike hypersurfaces, respectively, and give examples. Integrability conditions for the distributions on a screen semi-invariant lightlike hypersurface of para-Sasakian manifolds are investigated. We obtain a para-Sasakian structure on the leaves of an integrable distribution of a screen semi-invariant lightlike hypersurface.

Acet, Bilal Eftal; K?l?c, Erol

2014-01-01

19

Benchmarking para Investimentos socialmente Responsáveis: ISE a experiência brasileira  

Microsoft Academic Search

Este artigo apresenta os desafios da criação e o desenvolvimento de uma nova ferramenta para o mercado de ações - o Índice de Sustentabilidade Empresarial (ISE) da Bovespa. Pretende-se demonstrar como o ISE tem se tornado uma ferramenta para destacar as empresas com estratégia de geração de valor por meio da sustentabilidade através da melhora contínua da metodologia. Os índices

ROBERTA SIMONETTI

20

Ortho/Para Ratio of Water Vapor in Comet Halley.  

National Technical Information Service (NTIS)

The ortho/para ratio of H2O is shown to be an invariant in the cometary coma. The dependence of ortho-para ratio on temperature in thermal equilibrium is given, and the nuclear-spin-temperature is defined. Its relation to the physical temperature of the c...

M. J. Mumma H. P. Larson H. A. Weaver

1986-01-01

21

Towards a double field theory on para-Hermitian manifolds  

SciTech Connect

In a previous paper, we have shown that the geometry of double field theory has a natural interpretation on flat para-Kähler manifolds. In this paper, we show that the same geometric constructions can be made on any para-Hermitian manifold. The field is interpreted as a compatible (pseudo-)Riemannian metric. The tangent bundle of the manifold has a natural, metric-compatible bracket that extends the C-bracket of double field theory. In the para-Kähler case, this bracket is equal to the sum of the Courant brackets of the two Lagrangian foliations of the manifold. Then, we define a canonical connection and an action of the field that correspond to similar objects of double field theory. Another section is devoted to the Marsden-Weinstein reduction in double field theory on para-Hermitian manifolds. Finally, we give examples of fields on some well-known para-Hermitian manifolds.

Vaisman, Izu [Department of Mathematics, University of Haifa, Haifa (Israel)] [Department of Mathematics, University of Haifa, Haifa (Israel)

2013-12-15

22

Properties of Armos Para-Aramid Fibres in Conditions of Use. Comparison with Other Para-Aramids  

Microsoft Academic Search

The mechanical, thermal, and hygroscopic properties of Armos fibres and thread and their resistance to active media and other effects during use were analyzed. In comparing the structure and properties of Armos with other types of para-aramid fibres and thread, it was found that in the para-aramid series, Armos is distinguished by a unique combination of strength and flame resistance.

K. E. Perepelkin; N. N. Machalaba; V. A. Kvartskheliya

2001-01-01

23

¿Son las políticas locales una buena estrategia para dinamizar el mercado de trabajo? Algunos elementos para el caso colombiano  

Microsoft Academic Search

Resumen: En períodos de bajo crecimiento económico, tiempos de recesión o crisis económica, implementar una política fiscal contra-cíclica puede ser una herramienta fundamental para crear empleo y dinamizar la economía. En Colombia, específicamente en las principales ciudades del país existe una posibilidad concreta para que los gobiernos locales, a través de incrementos del gasto de inversión, impacten positivamente en la

Diana Galvis G; Mauricio López Gonzalez

2010-01-01

24

A Model of the Para-Terphenyl Dye Laser (Un Modele du Laser a Colorant Para-Terphenyl).  

National Technical Information Service (NTIS)

A theoretical model for a Para-Terphenyl dye laser pumped by an excimer laser has been developed. A new set of reaction-rate coefficients for Para-Terphenyl has been established. The problem of spontaneous emission in a dye has been solved analytically. T...

G. Fournier

1981-01-01

25

Autoguía para el telescopio 2,15 mts de CASLEO  

NASA Astrophysics Data System (ADS)

Se está desarrollando un sistema de autoguía para el telescopio de 2,15 mts. El mismo se realizará aprovechando el Offset Guider. Al ocular móvil de éste se vinculará alguna cámara digital (ST4-ST7-CH250) para lograr la visión del objeto. El funcionamiento del equipo será el siguiente: primero, dadas las coordenadas del objeto a observar, se tomarán las coordenadas del telescopio para que, a través de una base de datos, se determine un campo de objetos que sirvan para la cámara de visión, luego, la PC obtendrá el offset entre la estrella de observación y la estrella seleccionada como guía, este valor será trasladado a los motores que posicionarán en forma automática el ocular. Una vez que la estrella es visualizada en la cámara (monitor de PC ) se correrá el programa que guiará el telescopio automáticamente.

Aballay, J. A.; Casagrande, A. R.; Pereyra, P. F.; Marún, A. H.

26

Control del dolor: Apoyo para las personas con cáncer  

Cancer.gov

Libro sobre el control del dolor en pacientes con cáncer. Cubre los métodos y medicinas, así como los efectos físicos y emocionales del dolor. Es una adaptación cultural para el público de habla hispana del libro en inglés Pain Control.

27

Confocal Interferometer Without the Para-Axial Approximation.  

National Technical Information Service (NTIS)

The perturbed eigenfunctions of the confocal cavity without the para-axial condition are obtained. It is shown that in spite of the perturbation being small, the eigenfunctions change appreciably. (Atomindex citation 10:459675)

E. Gerck O. Andrade

1978-01-01

28

La quimioterapia y usted: Apoyo para las personas con cáncer  

Cancer.gov

Publicación para personas que van a recibir o que ya están recibiendo quimioterapia contra el cáncer. Contiene información sobre la quimioterapia y sus efectos secundarios y describe cómo puede cuidarse durante y después del tratamiento.

29

La radioterapia y usted: Apoyo para las personas con cáncer  

Cancer.gov

E-book para personas que van a recibir o que ya están recibiendo radioterapia contra el cáncer. Contiene información sobre la radioterapia y sus efectos secundarios y describe cómo puede cuidarse durante y después del tratamiento.

30

Preguntas para el doctor si tiene un cáncer avanzado  

Cancer.gov

Serie de preguntas que los pacientes con cáncer pueden hacerle al médico sobre las opciones de tratamiento si el cáncer es avanzado, las formas de controlar los síntomas y cómo prepararse para la etapa final de la vida.

31

La terapia hormonal para la menopausia y el cáncer  

Cancer.gov

Hoja informativa acerca de los resultados de los estudios sobre el uso de la terapia hormonal para la menopausia. Incluye información sobre el efecto de esta terapia en el cuerpo y explica los riesgos y beneficios del uso de hormonas.

32

40 CFR 721.9520 - Methylated-para-rosaniline salt of a trisulfonated triarylmethane dye (generic).  

Code of Federal Regulations, 2010 CFR

... false Methylated-para-rosaniline salt of a trisulfonated triarylmethane dye...9520 Methylated-para-rosaniline salt of a trisulfonated triarylmethane dye...generically as methylated-para-rosaniline salt of a trisulfonated triarylmethane...

2010-07-01

33

Chylous ascites following para-aortic lymphadenectomy: a case report  

Microsoft Academic Search

Background. Chylous ascites is an uncommon complication following para-aortic lymph node dissection in the management of gynecologic malignancies. Treatment options are serial paracentesis, medium-chain triglyceride diet, total parenteral nutrition and somatostatin as conservative management and peritoneovenous shunting, and surgical exploration for refractory cases.Case. A 31-year-old female patient developed chylous ascites following para-aortic lymph node dissection for borderline mucinous tumor of

Nurettin Boran; Aylin Pelin Cil; Gokhan Tulunay; Nejat Ozgul; M. Faruk Kose

2004-01-01

34

Cooling by conversion of para to ortho-hydrogen  

NASA Technical Reports Server (NTRS)

The cooling capacity of a solid hydrogen cooling system is significantly increased by exposing vapor created during evaporation of a solid hydrogen mass to a catalyst and thereby accelerating the endothermic para-to-ortho transition of the vapor to equilibrium hydrogen. Catalyst such as nickel, copper, iron or metal hydride gels of films in a low pressure drop catalytic reactor are suitable for accelerating the endothermic para-to-ortho conversion.

Sherman, A. (inventor)

1983-01-01

35

ParaText : scalable text modeling and analysis.  

SciTech Connect

Automated processing, modeling, and analysis of unstructured text (news documents, web content, journal articles, etc.) is a key task in many data analysis and decision making applications. As data sizes grow, scalability is essential for deep analysis. In many cases, documents are modeled as term or feature vectors and latent semantic analysis (LSA) is used to model latent, or hidden, relationships between documents and terms appearing in those documents. LSA supplies conceptual organization and analysis of document collections by modeling high-dimension feature vectors in many fewer dimensions. While past work on the scalability of LSA modeling has focused on the SVD, the goal of our work is to investigate the use of distributed memory architectures for the entire text analysis process, from data ingestion to semantic modeling and analysis. ParaText is a set of software components for distributed processing, modeling, and analysis of unstructured text. The ParaText source code is available under a BSD license, as an integral part of the Titan toolkit. ParaText components are chained-together into data-parallel pipelines that are replicated across processes on distributed-memory architectures. Individual components can be replaced or rewired to explore different computational strategies and implement new functionality. ParaText functionality can be embedded in applications on any platform using the native C++ API, Python, or Java. The ParaText MPI Process provides a 'generic' text analysis pipeline in a command-line executable that can be used for many serial and parallel analysis tasks. ParaText can also be deployed as a web service accessible via a RESTful (HTTP) API. In the web service configuration, any client can access the functionality provided by ParaText using commodity protocols ... from standard web browsers to custom clients written in any language.

Dunlavy, Daniel M.; Stanton, Eric T.; Shead, Timothy M.

2010-06-01

36

Direct His bundle and paraHisian cardiac pacing.  

PubMed

The success rate of direct His bundle pacing (DHBP) and paraHisian pacing has improved remarkably in the last 3-5 years with the advent of dedicated fixation systems that have reduced procedural duration, dislodgement rate, and fluoroscopy time. The methodology of DBHP remains still more complex than paraHisian pacing and is associated with high-pacing thresholds. Thus, DHBP entails greater battery current drain and reduced device longevity. A shift toward paraHisian pacing (which is fusion pacing of myocardium and His bundle) has occurred because its implementation is easier and the electrical parameters are superior to those of DBHP. Currently, an additional safety lead is inserted at the RV apex or outflow tract to prevent asystole, especially in patients with pure DHBP. It is often possible to avoid a safety lead with paraHisian pacing because ventricular pacing is virtually assured on a long-term basis via myocardial capture. DBHP and paraHisian pacing can be achieved in a substantial proportion of patients with varying grades of narrow QRS AV block or after AV junctional ablation and in some patients with the ECG manifestation of bundle branch block caused by an intraHisian lesion. Preliminary observations suggest that DHBP may be useful in some patients requiring cardiac resynchronization if it produces a narrow QRS complex because the site of an intraHisian lesion responsible for left bundle branch block is above the site of DHBP. PMID:22537323

Zanon, Francesco; Barold, S S

2012-04-01

37

El diseño final del espectrógrafo de banco (EBASIM) para CASLEO  

NASA Astrophysics Data System (ADS)

Utilizando el código de óptica ACCOS V se ha finalizado el diseño del espectrógrafo de banco para CASLEO. En una comunicación anterior habíamos indicado que utilizaríamos un colimador de 150 mm de diámetro con un radio de curvatura de 1540 mm. Para el espejo cámara, que tiene un diámetro de 200 mm, el radio de curvatura es de 1200 mm, ambos radios con una tolerancia no mayor a los 3 mm. En la presente, se informa sobre los detalles finales del cálculo del espectrógrafo que incluye el cómputo para 5 longitudes de onda diferentes y alrededor de 100 rayos. En todos los casos el 75 % de energía está dentro de un diámetro de 13 micrones. El diseño ha sido probado entre 3500 Å hasta 9000 Å con resultados satisfactorios.

Simmons, J.; Levato, H.

38

Laparoscopic repair of a right para duodenal hernia.  

PubMed

Para duodenal hernia is among the uncommon and rare causes of intestinal obstruction, but it is the most common type of internal hernia in abdomen and accounts for more than half of cases that do occur. Here, we are reporting a case of right Para duodenal hernia, reduced and repaired laparoscopically. This thirteen year old girl presented to us with features of small bowel obstruction of two days duration. Plain abdominal X-ray showed multiple fluid levels confined to right side of abdomen. A diagnostic laparoscopy was done under General Anaesthesia. Right Para duodenal hernia was found with small bowel confined to the right side between the ascending colon and hepatic flexure of colon. Laparoscopic reduction of contents of the hernia was done starting from the Ileocaecal junction. Hernial opening was closed laparoscopically with nonabsorbable suture. Patient is quite well till date and has had no recurrence of symptoms. PMID:20407574

Bhartia, Vishnu; Kumar, Anil; Khedkar, Indira; Savita, K S; Goel, N

2009-10-01

39

Laparoscopic repair of a right para duodenal hernia  

PubMed Central

Para duodenal hernia is among the uncommon and rare causes of intestinal obstruction, but it is the most common type of internal hernia in abdomen and accounts for more than half of cases that do occur. Here, we are reporting a case of right Para duodenal hernia, reduced and repaired laparoscopically. This thirteen year old girl presented to us with features of small bowel obstruction of two days duration. Plain abdominal X-ray showed multiple fluid levels confined to right side of abdomen. A diagnostic laparoscopy was done under General Anaesthesia. Right Para duodenal hernia was found with small bowel confined to the right side between the ascending colon and hepatic flexure of colon. Laparoscopic reduction of contents of the hernia was done starting from the Ileocaecal junction. Hernial opening was closed laparoscopically with nonabsorbable suture. Patient is quite well till date and has had no recurrence of symptoms

Bhartia, Vishnu; Kumar, Anil; Khedkar, Indira; Savita, K S; Goel, N

2009-01-01

40

Astronomia para/com crianças carentes em Limeira  

NASA Astrophysics Data System (ADS)

Em 2001, o Instituto Superior de Ciências Aplicadas (ISCA Faculdades de Limeira) iniciou um projeto pelo qual o Observatório do Morro Azul empreendeu uma parceria com o Centro de Promoção Social Municipal (CEPROSOM), instituição mantida pela Prefeitura Municipal de Limeira para atender crianças e adolescentes carentes. O CEPROSOM contava com dois projetos: Projeto Centro de Convivência Infantil (CCI) e Programa Criança e Adolescente (PCA), que atendiam crianças e adolescentes em Centros Comunitários de diversas áreas da cidade. Esses projetos têm como prioridades estabelecer atividades prazerosas para as crianças no sentido de retirá-las das ruas. Assim sendo, as crianças passaram a ter mais um tipo de atividade - as visitas ao observatório. Este painel descreve as várias fases do projeto, que envolveu: reuniões de planejamento, curso de Astronomia para as orientadoras dos CCIs e PCAs, atividades relacionadas a visitas das crianças ao Observatório, proposta de construção de gnômons e relógios de Sol nos diversos Centros Comunitários de Limeira e divulgação do projeto na imprensa. O painel inclui discussões sobre a aprendizagem de crianças carentes, relatos que mostram a postura das orientadoras sobre a pertinência do ensino de Astronomia, relatos do monitor que fez o atendimento no Observatório e o que o número de crianças atendidas representou para as atividades da instituição desde o início de suas atividades e, em particular, em 2001. Os resultados são baseados na análise de relatos das orientadoras e do monitor do Observatório, registros de visitas e matérias da imprensa local. Conclui com uma avaliação do que tal projeto representou para as Instituições participantes. Para o Observatório, em particular, foi feita uma análise com relação às outras modalidades de atendimentos que envolvem alunos de escolas e público em geral. Também é abordada a questão do compromisso social do Observatório na educação do público em questão.

Bretones, P. S.; Oliveira, V. C.

2003-08-01

41

Usina de ciências: um espaço pedagógico para aprendizagens múltiplas  

NASA Astrophysics Data System (ADS)

Entendemos que o Ensino de Astronomia é especialmente apropriado para motivar os alunos e aprofundar conteúdos em diversas áreas do conhecimento, pois envolve temas ligados à Física, Matemática, Química, Computação, Tratamento de Imagens e Instrumentação de Alta Precisão, além daqueles pertinentes as áreas de Geografia, História e Antropologia. Contudo, apesar do caráter interdisciplinar que esta ciência possui, a realidade atual é que a maioria dos professores em sala de aula não foram devidamente capacitados, durante o período de formação acadêmica, para ministrar conteúdos de Astronomia nos atuais Ensinos Fundamental e Médio. Neste trabalho, discutiremos de maneira ampla, num primeiro momento, a realidade do atual ensino de ciências praticado no Estado da Bahia, apontando por dependência administrativa, o crescimento e a redução do número de escolas, da taxa de analfabetismo por faixa etária, da escolarização, do atendimento, da aprovação, reprovação e abandono, de equipamentos e laboratórios e o grau de formação dos nossos atuais professores em pleno exercício de atividade docente. Num segundo momento, discutiremos o papel do Observatório Astronômico Antares/UEFS dentro desse contexto, ou seja, suas ações implementadas ao longo dos últimos anos e em particular, o recente projeto de extensão Ensino e Difusão de Astronomia, financiado pela Fundação Vitae, que procura traduzir no lúdico, no brincar de ciências, um espaço pedagógico para aprendizagens múltiplas. Neste, o papel do professor multiplicador associado ao laboratório de kits didáticos, de fácil construção e manipulação (alguns dos quais serão mostrados), perfazem os principais veículos para o desenvolvimento de conhecimentos, atitudes, habilidades e valores que preparam os nossos alunos para a carreira técnico-científica e para sua participação crítica e criativa na Sociedade.

Martin, V. A. F.; Poppe, P. C. R.; Orrico, A. C. P.; Pereira, M. G.

2003-08-01

42

Instrumentos económicos para la gestión de residuos sólidos  

Microsoft Academic Search

Esta presentación discute industria del reciclaje, incluye el caso de botellas PET en Río de Janeiro y el caso de sistema reciclaje de la Municipalidad de La Reina, Santiago; mercado de servicios, incluye el caso de apertura del mercado para usuarios no residenciales en Río de Janeiro y el caso de participación privada en Santiago; gestión integral, incluye el caso

Jorge Ducci

2003-01-01

43

Para-acetabular periarthritis calcarea: Its radiographic manifestations  

Microsoft Academic Search

On retrospective reviews of radiographs, periarthritis calcarea was distinguished from os acetabula by interval radiographic progression and regression. Among 59 men and 51 women, there were 137 instances of para-acetabular calcifications and ossifications, which were morphologically classified as 58 discrete, 58 amorphous, and 21 segmented types. Correlations with other radiographic abnormalities, symptoms, signs, and laboratory abnormalities were sought, but not

Akira Kawashima; Sadayuki Murayama; Toshiyuki Ohuchida; Walter J. Russell

1988-01-01

44

Notas para la Regulación Eficiente de la Transmisión Eléctrica  

Microsoft Academic Search

El proyecto de “ley corta” de electricidad propone importantes modificaciones a la actual regulación de la transmisión eléctrica en Chile. En este artículo desarrollamos un modelo simple para analizar dos de las propuestas centrales del proyecto: (i) el traspaso directo de parte de los costos de transmisión a los consumidores, y (ii) la planificación centralizada de la expansión de la

Juan Pablo Montero; Salvador Valdés

2003-01-01

45

Tumours Linked to Para-Occupational Exposure to Airborne Asbestos  

Microsoft Academic Search

Members of the households of former asbestos workers are at a higher risk of dying from mesothelioma resulting from asbestos exposure from cleaning asbestos-contaminated working clothes of their relatives at home. The lung fibre burdens of some of those who develop mesothelioma are similar even to those of former asbestos workers. Such people are said to be para-occupation- ally exposed.

Joachim Schneider; Hans-Joachim Woitowitz

1996-01-01

46

Nuevos sistemas de frecuencia intermedia para el IAR  

Microsoft Academic Search

Se presenta el diagrama en bloques de los nuevos sistemas de Frecuencia Intermedia para los dos radiómetros instalados en el IAR. Entre las características más importantes del sistema podemos mencionar la posibilidad de conectar cualquiera de las dos antenas a los ``backend\\

J. C. Olalde; D. Perilli; J. J. Larrarte

1996-01-01

47

Fungi associated with leaf litter of para rubber (Hevea brasiliensis)  

Microsoft Academic Search

The objective of this research was to study the diversity of fungi associated with the degradation of para rubber leaf litter. Samples were collected at three periods in 2010: January (during the late rainy season), April (during the dry season) and July (early in the rainy season) in Nakhon Si Thammarat and Songkhla Provinces, both in southern Thailand. Each sample

P. Seephueak; V. Petcharat; S. Phongpaichit

2010-01-01

48

Analyzing and Visualizing Cosmological Simulations with ParaView  

SciTech Connect

The advent of large cosmological sky surveys - ushering in the era of precision cosmology - has been accompanied by ever larger cosmological simulations. The analysis of these simulations, which currently encompass tens of billions of particles and up to a trillion particles in the near future, is often as daunting as carrying out the simulations in the first place. Therefore, the development of very efficient analysis tools combining qualitative and quantitative capabilities is a matter of some urgency. In this paper, we introduce new analysis features implemented within ParaView, a fully parallel, open-source visualization toolkit, to analyze large N-body simulations. A major aspect of ParaView is that it can live and operate on the same machines and utilize the same parallel power as the simulation codes themselves. In addition, data movement is in a serious bottleneck now and will become even more of an issue in the future; an interactive visualization and analysis tool that can handle data in situ is fast becoming essential. The new features in ParaView include particle readers and a very efficient halo finder that identifies friends-of-friends halos and determines common halo properties, including spherical overdensity properties. In combination with many other functionalities already existing within ParaView, such as histogram routines or interfaces to programming languages like Python, this enhanced version enables fast, interactive, and convenient analyses of large cosmological simulations. In addition, development paths are available for future extensions.

Woodring, Jonathan [Los Alamos National Laboratory (LANL); Heitmann, Katrin [ORNL; Ahrens, James P [ORNL; Fasel, Patricia [Los Alamos National Laboratory (LANL); Hsu, Chung-Hsing [ORNL; Habib, Salman [ORNL; Pope, Adrian [Los Alamos National Laboratory (LANL)

2011-01-01

49

Do lar para as ruas: capitalismo, trabalho e feminismo  

Microsoft Academic Search

Neste artigo, busca-se discutir as influências sociais, culturais e econômicas que contribuíram para a formulação de um discurso e práticas coletivas feministas 1 . Com efeito, esse discurso passou a se manifestar na Europa e nos Estados Unidos ainda no século XIX, sendo que, no caso do Brasil, o mesmo fenômeno ocorreu nas últimas décadas deste e nos primórdios do

Natalia Pietra Méndez

50

Ambiente para la Captura y Administración de Versiones de Modelos  

Microsoft Academic Search

El proceso de desarrollo de modelos para la gestión, investigación, producción, etc., en general involucra actividades creativas, que frecuentemente son poco estructuradas, es decir, no existe un flujo de trabajo definido previamente. Durante este proceso se genera un gran número de modelos de distinto nivel de abstracción del objeto que se desarrolla, el cual puede consistir en un sistema de

Diego Sánchez Schenone; Silvio Gonnet; Horacio Leone

51

ACUTE TOXICITY OF PARA-NONYLPHENOL TO SALTWATER ANIMALS  

EPA Science Inventory

?para-Nonylphenol (PNP), a mixture of alkylphenols used in producing nonionic surfactants, is distributed widely in surface waters and aquatic sediments, where it can affect saltwater species. This article describes a database for acute toxicity of PNP derived for calculating a n...

52

Terapias adyuvantes y neoadyuvantes para el cáncer de seno  

Cancer.gov

Hoja informativa que explica las terapias adyuvantes (tratamiento que se administra además de la terapia primaria para aumentar la posibilidad de supervivencia a largo plazo) y las neoadyuvantes (terapia que se administra antes de la terapia principal). Contiene información sobre los efectos secundarios y sobre los riesgos y beneficios de estas terapias.

53

ParaView and visualization on the TeraGrid  

NSDL National Science Digital Library

Overview on starting and running ParaView on the TeraGrid. With provided data, the tutorial instructs how to load the data, change the display mode, and edit the color map. It also shows how to add isosurfaces and cutting planes.

Teragrid

54

Comparison of dissociation tendencies of meta- & para- trifluorotolylglycine methyl esters and meta- & para- tolylglycine methyl esters in ESI-MS  

Microsoft Academic Search

Peptide fragmentation is an integral part of an evolving field commonly referred to as proteomics. Understanding of peptide fragmentation is vital to continued proteomic research. The frame work of this study was the benzylglycine methyl ester with either a methyl or trifluoromethyl constituent in the para- and meta-positions of the benzyl ring. The glycine methyl ester was coupled to the

Dale Kerstetter; Anthony Vu; Adam Graichen; Richard Vachet; Idia Tokunboh; Mike Van Stipdonk

55

NCI Anuncia Contribuciones para Incrementar Acceso de Minorías a Información sobre el Cáncer  

Cancer.gov

El Instituto Nacional del Cáncer (NCI) anunció este mes una variedad de contribuciones que totalizan casi 1 millón de dólares para ayudar a desarrollar la investigación y programas para comprender y finalmente romper la División Digital que existe en muchas poblaciones minoritarias para el acceso y uso de la información sobre el cáncer disponible en la Internet. Las contribuciones son un esfuerzo del Servicio de Información sobre el Cáncer (CIS), dependiente de la NCI, para trabajar con grupos y organizaciones regionales para el control del cáncer para probar estrategias destinadas a aumentar las comunicaciones sobre el cáncer en comunidades deficientemente atendidas

56

Focal para-hisian atrial tachycardia with dual exits.  

PubMed

Focal atrial tachycardias (AT) in the right atrium (RA) tend to cluster around the crista terminalis, coronary sinus (CS) region, tricuspid annulus, and para-hisian region. In most cases, the AT focus can be identified by careful activation mapping, and completely eliminated by radiofrequency (RF) catheter ablation. However, RF ablation near the His bundle (HB) carries a risk of inadvertent damage to the atrioventricular (AV) conduction system. Here we describe a patient with an AT originating in the vicinity of the AV node, which was successfully ablated earlier from non-coronary aortic cusp (NCC), and recurred with an exit from para-hisian location. Respiratory excursions of the catheter were associated with migration to the area of HIs. This was successfully ablated during controlled apnoea, using 3D electroanatomic mapping. PMID:23993015

Lawrance Jesuraj, M; Sharada, K; Sridevi, C; Narasimhan, C

2013-01-01

57

Focal para-hisian atrial tachycardia with dual exits  

PubMed Central

Focal atrial tachycardias (AT) in the right atrium (RA) tend to cluster around the crista terminalis, coronary sinus (CS) region, tricuspid annulus, and para-hisian region. In most cases, the AT focus can be identified by careful activation mapping, and completely eliminated by radiofrequency (RF) catheter ablation. However, RF ablation near the His bundle (HB) carries a risk of inadvertent damage to the atrioventricular (AV) conduction system. Here we describe a patient with an AT originating in the vicinity of the AV node, which was successfully ablated earlier from non-coronary aortic cusp (NCC), and recurred with an exit from para-hisian location. Respiratory excursions of the catheter were associated with migration to the area of HIs. This was successfully ablated during controlled apnoea, using 3D electroanatomic mapping.

Lawrance Jesuraj, M.; Sharada, K.; Sridevi, C.; Narasimhan, C.

2013-01-01

58

Validation of the Escala de Inteligencia Wechsler Para Adultos  

Microsoft Academic Search

This study examined the comparability between the Wechsler Adult Intelligence Scale-Revised (WAIS-R) and its Spanish-language adaptation the Escala De Inteligencia Para Adultos (EIWA). Fifty Puerto Rican, bilingual examinees who showed equal language proficiency in English and Spanish using the Bilingual Syntax Measure II (BSM-II) were administered both intelligence tests.^ Results of this study showed a mean difference between the EIWA

Carlos Y Maldonado

1995-01-01

59

DYNA3D\\/ParaDyn Regression Test Suite Inventory  

Microsoft Academic Search

The following table constitutes an initial assessment of feature coverage across the regression test suite used for DYNA3D and ParaDyn. It documents the regression test suite at the time of production release 10.1 in September 2010. The columns of the table represent groupings of functionalities, e.g., material models. Each problem in the test suite is represented by a row in

Lin

2011-01-01

60

On Linear Differential Equations Involving a Para-Grassmann Variable  

NASA Astrophysics Data System (ADS)

As a first step towards a theory of differential equations involving para-Grassmann variables the linear equations with constant coefficients are discussed and solutions for equations of low order are given explicitly. A connection to n-generalized Fibonacci numbers is established. Several other classes of differential equations (systems of first order, equations with variable coefficients, nonlinear equations) are also considered and the analogies or differences to the usual (''bosonic'') differential equations discussed.

Mansour, Toufik; Schork, Matthias

2009-07-01

61

Utilização de hardware reconfigurável para acelerar a satisfação booleana  

Microsoft Academic Search

* Trabalho financiado com a bolsa da FCT-PRAXIS XXI\\/BD\\/21353\\/99 Resumo - Este artigo apresenta um estudo de possibilidade de aceleração da satisfação booleana com a ajuda do hardware reconfigurável. A satisfação booleana (SAT) é um problema importante que tem muitas aplicações em CAD e outras áreas. Neste artigo propomos uma técnica de desenvolvimento orientada a problema em geral para acelerar

Iouliia Skliarova; António B. Ferrari

2001-01-01

62

Microbial conversion of glucose to para-hydroxystyrene  

US Patent & Trademark Office Database

An in vivo method for the production of pHS via a recombinant host cell is disclosed. The host cell expresses at least one gene encoding a polypeptide having para-hydroxycinnamic acid decarboxylase activity in combination with either at least one gene encoding a polypeptide having tyrosine ammonia lyase activity or at least one gene encoding a polypeptide having phenylalanine ammonia lyase activity.

2007-06-12

63

Edukalibre: una herramienta para la creacion colaborativa de material didactico  

Microsoft Academic Search

El Software Libre, con sus caracter¶‡sticas y su particular modelo de desarrollo, ha permitido la creacion de un conjunto de metodolog¶‡as de trabajo en grupo que han resultado satisfactorias en gran cantidad diferentesambitos. En este sentido, el proyecto Edukalibre importa y adapta estas metodolog¶‡as para ser aplicadas en la creacion y man- tenimiento de documentacion en elambito de la educacion.

Diego Chaparro; Teofllo Romera

64

PARA-HYDROXYBENZOATE AS AN INTERMEDIATE IN THE ANAEROBIC TRANSFORMATION OF PHENOL TO BENZOATE  

EPA Science Inventory

Anaerobic phenol transformation was studied using a consortium which transformed phenol to benzoate without complete mineralization of benzoate. Products of monofluorophenol transformation indicate para-carboxylation. henol and benzoate were detected during para-hydroxybenzoate (...

65

A study of the valence shell electronic structure and photoionisation dynamics of para-dichlorobenzene and para-bromochlorobenzene  

NASA Astrophysics Data System (ADS)

The valence shell electronic structure and photoionisation dynamics of para-dichlorobenzene and para-bromochlorobenzene have been investigated both experimentally and theoretically. High resolution photoelectron spectra of the outer valence orbitals have been recorded with HeI radiation and the observed structure has been interpreted using calculated ionisation energies and spectral intensities. The theoretical predictions for the single-hole ionic states due to outer valence ionisation agree satisfactorily with the experimental results. Ionisation from the inner valence orbitals is strongly influenced by many-body effects and the with a particular orbital is spread amongst numerous satellites. Some of the photoelectron bands exhibit vibrational progressions and tentative assignments have been proposed. The photoionisation dynamics of the outer valence orbitals of para-dichlorobenzene have been investigated theoretically by using the continuum multiple scattering approach to calculate photoionisation partial cross-sections and photoelectron anisotropy parameters. The results show that ionisation from some of the orbitals is affected by the Cooper minimum associated with the chlorine atom. Synchrotron radiation has been used to record angle resolved photoelectron spectra of the entire valence shell, for photon energies between threshold and ˜100 eV, and these have allowed the corresponding experimental data to be derived. A comparison between the predicted and measured anisotropy parameters confirms the influence of the Cooper minimum in those orbitals related to the chlorine lone-pairs.

Powis, I.; Trofimov, A. B.; Bodzuk, I. L.; Holland, D. M. P.; Potts, A. W.; Karlsson, L.

2013-03-01

66

Opciones de cirugía para mujeres con CDIS o con cáncer de seno  

Cancer.gov

Folleto para mujeres con CDIS o con cáncer de seno que pueden operarse con cirugía. Esta guía explica los tipos de cirugía de seno, como la operación para preservar el seno y la mastectomía, y ayuda a las mujeres a decidir cuál cirugía es la mejor opción para ellas.

67

Consideraciones para el desarrollo de la creatividad y la enseñanza problémica en el aula  

Microsoft Academic Search

La “Metodología para estimular y desarrollar la creatividad técnica a través de la enseñanza del dibujo básico” ofrece un material docente contentivo con un conjunto de orientaciones e indicaciones que contribuya a estimular la creatividad técnica en la solución de problemas técnicos para los estudiantes que cursan carreras técnicas y como vía para la capacitación de los docentes. La misma

Angel Carvajal Castillo; María Elena Sierra Sandoval

2011-01-01

68

Opciones de cirugía para mujeres con CDIS o con cáncer de seno  

Cancer.gov

E-book para mujeres con CDIS o con cáncer de seno que pueden operarse con cirugía. Esta guía explica los tipos de cirugía de seno, como la operación para preservar el seno y la mastectomía, y ayuda a las mujeres a decidir cuál cirugía es la mejor opción para ellas.

69

LABORATORIO REMOTO PARA LA PROGRAMACIÓN DE ROBOTS INDUSTRIALES ABB EN LENGUAJE RAPID  

Microsoft Academic Search

El aprendizaje efectivo del lenguaje de programación para robots necesita de una constante realización de prácticas. Este trabajo describe la metodología llevada a cabo para conseguir el aprendizaje del lenguaje RAPID. Se ha desarrollado un sistema de aprendizaje para prácticas remotas y presenciales que emplea un robot IRB140 de ABB, un PLC con tarjeta Ethernet y servidor web, una cámara

A. ROSADO; R. SEGURA; G. RUIZ; J. MUÑOZ; R. MAGDALENA

70

Ortho-to-para ratio of interstellar heavy water  

NASA Astrophysics Data System (ADS)

Context. Despite the low elemental deuterium abundance in the Galaxy, enhanced molecular D/H ratios have been found in the environments of low-mass star-forming regions, and in particular the Class 0 protostar IRAS 16293-2422. Aims: The CHESS (Chemical HErschel Surveys of Star forming regions) key program aims to study the molecular complexity of the interstellar medium. The high sensitivity and spectral resolution of the Herschel/HIFI instrument provide a unique opportunity to observe the fundamental 11,1-00,0 transition of the ortho-D2O molecule, which is inaccessible from the ground, and determine the ortho-to-para D2O ratio. Methods: We detected the fundamental transition of the ortho-D2O molecule at 607.35 GHz towards IRAS 16293-2422. The line is seen in absorption with a line opacity of 0.62 ± 0.11 (1?). From the previous ground-based observations of the fundamental 11,0-10,1 transition of para-D2O seen in absorption at 316.80 GHz, we estimate a line opacity of 0.26 ± 0.05 (1?). Results: We show that the observed absorption is caused by the cold gas in the envelope of the protostar. Using these new observations, we estimate for the first time the ortho-to-para D2O ratio to be lower than 2.6 at a 3? level of uncertainty, which should be compared with the thermal equilibrium value of 2:1. Herschel is an ESA space observatory with science instruments provided by European-led principal Investigator consortia and with important participation from NASA.

Vastel, C.; Ceccarelli, C.; Caux, E.; Coutens, A.; Cernicharo, J.; Bottinelli, S.; Demyk, K.; Faure, A.; Wiesenfeld, L.; Scribano, Y.; Bacmann, A.; Hily-Blant, P.; Maret, S.; Walters, A.; Bergin, E. A.; Blake, G. A.; Castets, A.; Crimier, N.; Dominik, C.; Encrenaz, P.; Gérin, M.; Hennebelle, P.; Kahane, C.; Klotz, A.; Melnick, G.; Pagani, L.; Parise, B.; Schilke, P.; Wakelam, V.; Baudry, A.; Bell, T.; Benedettini, M.; Boogert, A.; Cabrit, S.; Caselli, P.; Codella, C.; Comito, C.; Falgarone, E.; Fuente, A.; Goldsmith, P. F.; Helmich, F.; Henning, T.; Herbst, E.; Jacq, T.; Kama, M.; Langer, W.; Lefloch, B.; Lis, D.; Lord, S.; Lorenzani, A.; Neufeld, D.; Nisini, B.; Pacheco, S.; Pearson, J.; Phillips, T.; Salez, M.; Saraceno, P.; Schuster, K.; Tielens, X.; van der Tak, F.; van der Wiel, M. H. D.; Viti, S.; Wyrowski, F.; Yorke, H.; Cais, P.; Krieg, J. M.; Olberg, M.; Ravera, L.

2010-10-01

71

Amazon Land Wars in the South of Para  

NASA Technical Reports Server (NTRS)

The South of Para, located in the heart of the Brazilian Amazon, has become notorious for violent land struggle. Although land conflict has a long history in Brazil, and today impacts many parts of the country, violence is most severe and persistent here. The purpose of this article is to examine why. Specifically, we consider how a particular Amazonian place, the so-called South of Para has come to be known as Brazil's most dangerous badland. We begin by considering the predominant literature, which attributes land conflict to the frontier expansion process with intensified struggle emerging in the face of rising property values and demand for private property associated with capitalist development. From this discussion, we distill a concept of the frontier, based on notions of property rights evolution and locational rents. We then empirically test the persistence of place-based violence in the region, and assess the frontier movement through an analysis of transportation costs. The findings from the analyses indicate that the prevalent theorization of frontier violence in Amazonia does little to explain its persistent and pervasive nature in the South of Para. To fill this gap in understanding, we develop an explanation based the geographic conception of place, and we use contentious politics theory heuristically to elucidate the ways in which general processes interact with place specific history to engender a landscape of violence. In so doing, we focus on environmental, cognitive, and relational mechanisms (and implicated structures), and attempt to deploy them in an explanatory framework that allows direct observation of the accumulating layers of the region's tragic history. We end by placing our discussion within a political ecological context, and consider the implications of the Amazon Land War for the environment.

Simmons, Cynthia S.; Walker, Robert T.; Arima, Eugenio Y.; Aldrich, Stephen P.; Caldas, Marcellus M.

2007-01-01

72

ORTHO-PARA SELECTION RULES IN THE GAS-PHASE CHEMISTRY OF INTERSTELLAR AMMONIA  

SciTech Connect

The ortho-para chemistry of ammonia in the cold interstellar medium is investigated using a gas-phase chemical network. Branching ratios for the primary reaction chain involved in the formation and destruction of ortho- and para-NH{sub 3} were derived using angular momentum rules based on the conservation of the nuclear spin. We show that the 'anomalous' ortho-to-para ratio of ammonia ({approx}0.7) observed in various interstellar regions is in fact consistent with nuclear spin selection rules in a para-enriched H{sub 2} gas. This ratio is found to be independent of temperature in the range 5-30 K. We also predict an ortho-to-para ratio of {approx}2.3 for NH{sub 2}. We conclude that a low ortho-to-para ratio of H{sub 2} naturally drives the ortho-to-para ratios of nitrogen hydrides below the statistical values.

Faure, A.; Hily-Blant, P.; Le Gal, R.; Rist, C. [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Pineau des Forets, G., E-mail: afaure@obs.ujf-grenoble.fr [Institut d'Astrophysique Spatiale, Universite Paris-Orsay and CNRS, Orsay (France)

2013-06-10

73

Peso Adulto de Matrizes em Rebanhos de Seleção da Raça Nelore no Brasil 1  

Microsoft Academic Search

The main objective of this work was to evaluate the Nellore breed in Brazil with respect to the phenotypic and genetic variation of the mature size of cows. The observations were taken from 34 herds of eleven different beef cattle product ion regions in the country. There were considered cows of the horned and polled varieties, raised on pastures, from

Nascimento Rosa; Henrique Nunes de Oliveira; Luiz Antonio; Framartino Bezerra

74

ANÁLISIS EXPERIMENTAL DE LOS MODELOS DIGITALES DE ELEVACIONES CON ESTRUCTURA DE MATRIZ REGULAR  

Microsoft Academic Search

In this work several empirical model are developed for the modeling of the accuracy of a grid digital elevation model (DEM) interpolated from scattered sample data. These models seek to explain what is known as information loss, i.e., the sum of the error purely due to sampling the continuous terrain surface with a finite grid interval and the interpolation error.

AGUILAR TORRES; AGÜERA VEGA; CARVAJAL RAMÍREZ; SÁNCHEZ LÓPEZ

75

Persistent molecular superfluid response in doped para-hydrogen clusters.  

PubMed

Direct observation of superfluid response in para-hydrogen (p-H(2)) remains a challenge because of the need for a probe that would not induce localization and a resultant reduction in superfluid fraction. Earlier work [H. Li, R. J. Le Roy, P.-N. Roy, and A. R. W. McKellar, Phys. Rev. Lett. 105, 133401 (2010)] has shown that carbon dioxide can probe the effective inertia of p-H(2) although larger clusters show a lower superfluid response due to localization. It is shown here that the lighter carbon monoxide probe molecule allows one to measure the effective inertia of p-H(2) clusters while maintaining a maximum superfluid response with respect to dopant rotation. Microwave spectroscopy and a theoretical analysis based on Feynman path-integral simulations are used to support this conclusion. PMID:23004599

Raston, P L; Jäger, W; Li, H; Le Roy, R J; Roy, P-N

2012-06-22

76

Persistent Molecular Superfluid Response in Doped Para-Hydrogen Clusters  

NASA Astrophysics Data System (ADS)

Direct observation of superfluid response in para-hydrogen (p-H2) remains a challenge because of the need for a probe that would not induce localization and a resultant reduction in superfluid fraction. Earlier work [H. Li, R. J. Le Roy, P.-N. Roy, and A. R. W. McKellar, Phys. Rev. Lett.PRLTAO0031-9007 105, 133401 (2010)10.1103/PhysRevLett.105.133401] has shown that carbon dioxide can probe the effective inertia of p-H2 although larger clusters show a lower superfluid response due to localization. It is shown here that the lighter carbon monoxide probe molecule allows one to measure the effective inertia of p-H2 clusters while maintaining a maximum superfluid response with respect to dopant rotation. Microwave spectroscopy and a theoretical analysis based on Feynman path-integral simulations are used to support this conclusion.

Raston, P. L.; Jäger, W.; Li, H.; Le Roy, R. J.; Roy, P.-N.

2012-06-01

77

ParaText : scalable text analysis and visualization.  

SciTech Connect

Automated analysis of unstructured text documents (e.g., web pages, newswire articles, research publications, business reports) is a key capability for solving important problems in areas including decision making, risk assessment, social network analysis, intelligence analysis, scholarly research and others. However, as data sizes continue to grow in these areas, scalable processing, modeling, and semantic analysis of text collections becomes essential. In this paper, we present the ParaText text analysis engine, a distributed memory software framework for processing, modeling, and analyzing collections of unstructured text documents. Results on several document collections using hundreds of processors are presented to illustrate the exibility, extensibility, and scalability of the the entire process of text modeling from raw data ingestion to application analysis.

Dunlavy, Daniel M.; Stanton, Eric T.; Shead, Timothy M.

2010-07-01

78

Technique to match mantle and para-aortic fields  

SciTech Connect

A technique is described to match the mantle and para-aortic fields used in treatment of Hodgkin's disease, when the patient is treated alternately in supine and prone position. The approach is based on referencing the field edges to a point close to the vertebral column, where uncontrolled motion is minimal and where accurate matching is particularly important. Fiducial surface points are established in the simulation process to accomplish the objective. Dose distributions have been measured to study the combined effect of divergence differences, changes in body angulation and setup errors. Even with the most careful technique, the use of small cord blocks of 50% transmission is an advisable precaution for the posterior fields.

Lutz, W.R.; Larsen, R.D.

1983-11-01

79

Sponges, Tubules and Modulated Phases of Para-Antinematic Membranes  

NASA Astrophysics Data System (ADS)

We theoretically analyze the behavior of membranes presenting a nematic susceptibility, induced by the presence of anisotropic phospholipids having a quadrupolar nematic symmetry. This kind of anisotropic phospholipids is either naturally found in some biological membranes, or can be chemically tailored by linking pairs of single surfactants at the level of their polar heads, giving rise to so-called “gemini” surfactants. We predict that such membranes can acquire a non-zero paranematic order induced by the membrane curvature, which in turn produces curvature instabilities. We call the resulting paranematic order para-antinematic, since it is opposite on opposite sides of the membrane. We find phase transitions toward sponges (L3), tubules, or modulated “egg-carton” phases.

Fournier, J. B.; Galatola, P.

1997-10-01

80

Cosmoeducação: uma proposta para o ensino de astronomia  

NASA Astrophysics Data System (ADS)

Entende-se por cosmoeducação o desenvolvimento vivencial da unidade homem-cosmo. Este conceito é norteado pela psicologia transpessoal, que estuda o ser humano em sua totalidade, onde suas relações ecológicas e cósmicas são de grande importância. Constata-se uma necessidade latente no ser humano moderno em resgatar uma relação holística com o Universo. Neste trabalho exploramos meios de cultivar a consciência de que o ser humano constitui parte integrante do cosmo e se relaciona com este com o objetivo de promover em si uma percepção ambiental mais ampla. Nossa hipótese de trabalho inicial foi que o ensino de conteúdos básicos em astronomia realizado através de uma abordagem holística, que incorpore práticas vivenciais correlacionadas àqueles conteúdos, pode despertar no indivíduo sua identidade cósmica. O método que utilizamos é o fenomenológico e o universo desta pesquisa é um grupo de estudantes da disciplina de Astronomia (Curso de Licenciatura em Geografia/UFRN), onde realizamos observação participante, entrevistas, depoimentos e as práticas vivenciais mencionadas. Neste caso estamos desenvolvendo e adaptando exercícios de algumas técnicas terapêuticas de psicologia transpessoal, que um de nós (LALM) tem aplicado no contexto clínico, para trabalhar aspectos cognitivos envolvidos naquele processo de conscientização cósmica. Resultados parciais claramente referendam a hipótese inicial. Um resultado a destacar é fruto de uma dinâmica de representação corporal interiorizada do eclipse lunar, envolvendo um pequeno grupo daqueles estudantes, na qual conteúdos míticos afloraram de maneira espontânea e contundente para todos, sugerindo ressonância, ou pelo menos isomorfismo, entre o macro e o microcosmo. Este e outros resultados são discutidos em detalhe neste trabalho. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP).

Medeiros, L. A. L.; Jafelice, L. C.

2003-08-01

81

A conversation robot using head gesture recognition as para-linguistic information  

Microsoft Academic Search

A conversation robot that recognizes user's head gestures and uses its results as para-linguistic information is developed. In the conversation, humans exchange linguistic information, which can be obtained by transcription of the utterance, and para-linguistic information, which helps the transmission of linguistic information. Para-linguistic information brings a nuance that cannot be transmitted by linguistic information, and the natural and effective

Shinya Fujie; Yasushi Ejiri; Kei Nakajima; Yosuke Matsusaka; Tetsunori Kobayashi

2004-01-01

82

Ammonium-excreting Azospirillum sp. become intracellularly established in maize ( Zea mays ) para-nodules  

Microsoft Academic Search

Maize seedlings develop nodule-like tumour knots (para-nodules) along primary roots when treated with the auxin 2,4-dichlor-phenoxy-acetic acid (2,4-D). Inoculated NH4+-excreting Azospirillum brasilense cells were shown to colonize these tumours, mostly intracellularly, promoting a high level of N2 fixation when microaerophilic conditions were imposed. The nitrogenase activity inside the para-nodules was less sensitive to free O2 than in non-para-nodulating roots. Both

C. Christiansen-Weniger; Jos Vanderleyden

1994-01-01

83

EQUAÇÕES DE VOLUME PARA A FLORESTA NACIONAL DO TAPAJÓS (Volume equations for the Tapajós National Forest)  

Microsoft Academic Search

Com o objetivo de atender a demanda de informações acerca de relações quantitativas para a Floresta Nacional do Tapajós, Estado do Pará, selecionaram-se equações de volume para andiroba (Carapa guianensis), abiurana (diversos gêneros), jutaí-açu (Hymenaea courbaril), jarana (Holopyxidium jarana), ucuuba- da-terra-firme (Virola sp), taxi-vermelho (Sclerolobium chrysophyllum), maçaranduba (Manilkara huberi), além de equações abrangentes, para qualquer espécie. Testaram-se 16 equações, nove

José Natalino Macedo Silva

84

CARACTERÍSTICAS PRODUTIVAS E QUALITATIVAS DE HÍBRIDOS DE MILHO PARA PRODUÇÃO DE SILAGEM  

Microsoft Academic Search

RESUMO - A avaliação dos genótipos de milho disponíveis no mercado é de grande interesse tanto para produtores como para pesquisadores da área de produção animal e vegetal. Nesse sentido, objetivou-se avaliar o potencial produtivo e qualitativo de híbri- dos de milho para a produção de silagem. Os tratamentos foram constituídos por seis híbridos de milho: DKB-215, DKB-344, C-747, AS-32,

RENIUS MELLO; JOSÉ LAERTE NÖRNBERG; MARTA GOMES DA ROCHA; DIEGO BITENCOURT DE DAVID

85

Nueva opción de tratamiento para mujeres jóvenes con cáncer de seno sensible a las hormonas  

Cancer.gov

Un fármaco usado para el tratamiento del cáncer de seno (mama), conocido como exemestano, es más eficaz que tamoxifeno, un fármaco preventivo de uso común para el cáncer de seno, en la prevención de la recidiva del cáncer de seno en mujeres jóvenes que también reciben tratamiento posoperativo para suprimir el funcionamiento ovárico. Los resultados de este estudio se presentaron en mujeres que tenían un tipo de cáncer de seno en estadio inicial sensible al tratamiento hormonal.

86

The Ratio of Ortho- to Para-H2 in Photodissociation Regions  

NASA Technical Reports Server (NTRS)

We discuss the ratio of ortho- to para-H2 in photodissociation regions (PDRs). We draw attention to an apparent confusion in the literature between the ortho-to-para ratio of molecules in FUV-pumped vibrationally excited states and the total H2 ortho-to-para abundance ratio. These ratios are not the same because the process of FUV pumping of fluorescent H2 emission in PDRs occurs via optically thick absorption lines. Thus gas with an equilibrium ratio of ortho- to para-H2 equal to 3 will yield FUV-pumped vibrationally excited ortho-to-para ratios smaller than 3, because the ortho-H2 pumping rates are preferentially reduced by optical depth effects. Indeed, if the ortho and para pumping lines are on the "square root" part of the curve of growth, then the expected ratio of ortho and para vibrational line strengths is 3(sup 1/2) approximately 1.7, close to the typically observed value. Thus, contrary to what has sometimes been stated in the literature, most previous measurements of the ratio of ortho- to para-H2 in vibrationally excited states are entirely consistent with a total ortho-to-para ratio of 3, the equilibrium value for temperatures greater than 200 K. We present an analysis and several detailed models that illustrate the relationship between the total ratios of ortho- to para-H2 and the vibrationally excited ortho-to-para ratios in PDRs. Recent Infrared Space Observatory measurements of pure rotational and vibrational H2 emissions from the PDR in the star-forming region S140 provide strong observational support for our conclusions.

Sternberg, Amiel; Neufeld, David A.

1999-01-01

87

Uninfected Para-Anastomotic Aneurysms after Infrarenal Aortic Grafting  

PubMed Central

Purpose This single-institution retrospective review examines the management of uninfected para-anastomotic aneurysms of the abdominal aorta (PAAA), developed after infrarenal grafting. Materials and Methods From October 1979 to November 2005, 31 PAAA were observed in our Department. Twenty-six uninfected PAAA of degenerative etiology, including 24 false and 2 true aneurysms, were candidates for intervention and retrospectively included in our database for management and outcome evaluation. Six (23%) patients were treated as emergencies. Surgery included tube graft interposition (n = 12), new reconstruction (n = 8), and graft removal with extra-anatomic bypass (n = 3). Endovascular management (n = 3) consisted of free-flow tube endografts. Results The mortality rate among the elective and emergency cases was 5% and 66.6%, respectively (p = 0.005). The morbidity rate in elective cases was 57.8%, whereas 75% in emergency cases (p = 0.99). The survival rate during the follow-up was significantly higher for elective cases than for emergency cases. Conclusion Uninfected PAAA is a late complication of aortic grafting, tends to evolve silently and is difficult to diagnose. The prevalence is underestimated and increases with time since surgery. The mortality rate is higher among patients treated as an emergency than among patients who undergo elective surgery, therefore, elective treatment and aggressive management in the case of pseudoaneurysm are the keys to obtain a good outcome. Endovascular treatment could reduce mortality. Patients who undergo infrarenal aortic grafting require life-long surveillance after surgery.

Nano, Giovanni; Cusmai, Francesco; Ramponi, Fabio; Stegher, Silvia; Dell'Aglio, Daniela; Malacrida, Giovanni; Tealdi, Domenico G.

2009-01-01

88

Evidence for para dechlorination of polychlorobiphenyls by methanogenic bacteria  

SciTech Connect

When microorganisms eluted from upper Hudson River sediment were cultured without any substrate except polychlorobiphenyl (PCB)-free Hudson River sediment, methane formation was the terminal step of the anaerobic food chain. In sediments containing Aroclor 1242, addition of eubacterium-inhibiting antibiotics, which should have directly inhibited fermentative bacteria and thereby should have indirectly inhibited methanogens, resulted in no dechlorination activity or methane production. However, when substrates for methanogenic bacteria were provided along with the antibiotics (to free the methanogens from dependence on eubacteria), concomitant methane production and dechlorination of PCBs were observed. The dechlorination of Aroclor 1242 was from the para positions, a pattern distinctly different from, and more limited than, the pattern observed with untreated or pasteurized inocula. Both methane production and dechlorination in cultures amended with antibiotics plus methanogenic substrates were inhibited by 2-bromoethanesulfonic acid. These results suggest that the methanogenic bacteria are among the physiological groups capable of anaerobic dechlorination of PCBs, but that the dechlorination observed with methanogenic bacteria is less extensive than the dechlorination observed with more complex anaerobic consortia. 27 refs., 5 figs., 1 tab.

Ye, D.; Quensen, J.F.; Tiedje, J.M. [Michigan State Univ., East Lansing, MI (United States)] [and others

1995-06-01

89

A Para-Canalicular Abscess Resembling an Inflamed Chalazion  

PubMed Central

Background. Lacrimal infections by Actinomyces are rare and commonly misdiagnosed for long periods of time. They account for 2% of all lacrimal diseases. Case Report. We report a case of a 70-year-old female patient suffering from a para-canalicular abscess in the medial canthus of the left eye, beside the lower punctum lacrimale, resembling a chalazion. Purulence exited from the punctum lacrimale due to inflammation of the inferior canaliculus (canaliculitis). When pressure was applied to the mass, a second exit of purulence was also observed under the palpebral conjunctiva below the lacrimal caruncle. A surgical excision was performed followed by administration of local antibiotic therapy. The histopathological examination of the extracted mass revealed the existence of actinomycosis. Conclusion. Persistent or recurrent infections and lumps of the eyelids should be thoroughly investigated. Actinomyces as a causative agent should be considered. Differential diagnosis is broad and should include canaliculitis, chalazion, and multiple types of neoplasias. For this reason, in nonconclusive cases, a histopathological examination should be performed.

Almaliotis, Diamantis; Nakos, Elias; Siempis, Thomas; Koletsa, Triantafyllia; Kostopoulos, Ioannis; Chatzipantazi, Maria; Karampatakis, Vasileios

2013-01-01

90

New gene responsible for para-aminobenzoate biosynthesis.  

PubMed

Folate is an essential cofactor in all living cells for one-carbon transfer reactions. para-Aminobenzoate (pABA), a building block of folate, is usually derived from chorismate in the shikimate pathway by reactions of aminodeoxychorismate synthase (PabA and -B) and 4-amino-4-deoxychorismate lyase (PabC). We previously suggested that an alternative pathway for pABA biosynthesis would operate in some microorganisms such as Lactobacillus fermentum and Nitrosomonas europaea since these bacteria showed a prototrophic phenotype to pABA despite the fact that there are no orthologs of pabA, -B, and -C in their genome databases. In this study, a gene of unknown function, NE1434, was obtained from N. europaea by shotgun cloning using a pABA-auxotrophic Escherichia coli mutant (?pabABC) as a host. A tracer experiment using [U-(13)C6]glucose suggested that pABA was de novo synthesized in the transformant. An E. coli ?pabABC?aroB mutant carrying the NE1434 gene exhibited a prototrophic phenotype to pABA, suggesting that compounds in the shikimate pathway including chorismate were not utilized as substrates by NE1434. Moreover, the CT610 gene, an ortholog of NE1434 located in the folate biosynthetic gene cluster in Chlamydia trachomatis, also complemented pABA-auxotrophic E. coli mutants. Taken together, these results suggest that NE1434 and CT610 participate in pABA biosynthesis. PMID:23972426

Satoh, Yasuharu; Kuratsu, Masahiro; Kobayashi, Daiki; Dairi, Tohru

2014-02-01

91

Para-dichlorobenzene toxicity - a review of potential neurotoxic manifestations  

PubMed Central

Background: Para-dichlorobenzene (PDCB) is an active ingredient of mothballs, deodorizers and fumigants. Due to the easy availability of this chemical, there is a considerable risk for accidental or intentional toxic exposure. Recently, multiple cases of PDCB toxicity due to mothball ingestion were reported. PDCB toxicity can affect multiple organ systems including liver, kidneys, skin, lung and the central nervous system (CNS). CNS toxicity often results in leukoencephalopathy and heterogeneous neurological manifestations. Objectives: The objective of this study was to illustrate the clinical presentation, imaging findings, diagnosis and management of PDCB toxicity. Methods: We carried out a literature review of the pharmacological and toxicological properties of PDCB. Conclusions: PDCB and other aromatic hydrocarbons are capable of CNS tissue damage and in promoting functional neurological decline. While very little is currently known about prevalence of PDCB addiction, it cannot be ruled out that its illicit use among young people is under-recognized. The number of cases of PDCB toxicity might also rise due to the increasing industrial and domestic use of this chemical.

Dubey, Divyanshu; Sharma, Vibhash D.; Pass, Steven E.; Sawhney, Anshudha

2014-01-01

92

Anise oil as para-methoxyamphetamine (PMA) precursor.  

PubMed

These days, MDMA is one of the most popular drugs of abuse. Due to its illegality, MDMA and its chemical precursors are watched by governmental organizations in many countries. To avoid conflicts with legal instances, underground chemists have tried to market several new unregulated amphetamine analogues, such as 4-MTA. Para-methoxyamphetamine (PMA), on the other hand, is regulated by law but its precursors are easily obtained since they are cheap and unwatched. This article presents such a case, namely the large scale synthesis of PMA using anethole, a main constituent of anise oil, as precursor. Anethole has been converted to its phenyl acetone analogue via peracid oxidation, while PMA itself has been synthesized using this ketone as precursor in the Leuckart synthesis. The synthesis of PMA using anethole as starting product has been investigated applying GC/MS and GC-HSPME/MS techniques, hereby discovering new specific (4-methoxyphenol) and already identified synthesis impurities (4-methyl-5-(4-methoxyphenyl)pyrimidine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzyl methyl ketimine, 1-(4-methoxyphenyl)-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, 1-(4-methoxyphenyl)-N-methyl-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzaldimine). The new impurity 4-methoxyphenol is specific for the application of a peracid oxidation method where anethole is used as precursor. PMID:12742705

Waumans, Dieter; Bruneel, Noël; Tytgat, Jan

2003-04-23

93

Effect of thermal aging on the defectiveness of ultrastrong para-aromatic armos and SVM fibres  

Microsoft Academic Search

The change in the defectiveness of ultrastrong para-aromatic Armos and SVM fibres during thermal aging in air was investigated based on the scale dependences and coefficients of variation of the breaking characteristics: strength, elongation, and strain energy at break. The increase in the defectiveness of ultrastrong para-aromatic fibres during thermal aging can be more objectively assessed by the change in

K. E. Perepelkin; S. A. Baranova; E. Yu. Gurova

1995-01-01

94

Development of polymorphic microsatellite markers for the livebearing fish Poecilia parae  

Microsoft Academic Search

We developed 16 novel polymorphic tetranucleotide microsatellite markers for Poecilia parae, a livebearing fish used in evolutionary studies because of its Y-linked colour and size polymorphism. A set of 199 clones was sequenced out of an enriched genomic library, and we achieved an enrichment efficiency of nearly 80%. Primers were designed for 16 pure repeats, and 59 P. parae were

ALEXANDER NATER; MICHAEL KRÜTZEN; ANNA K. LINDHOLM

2008-01-01

95

WebAPSEE: Um Ambiente Livre e Flexível Para Gerência de Processos de Software1  

Microsoft Academic Search

This paper describes an open-source Flexible Environment for Software Development Process Management. Thus, it presents a process enactment scenario used by the NetBeans project in order show the main functionalities provided by the cited environment. Resumo. Este artigo descreve um Ambiente Flexível para Gerência de Processos de desenvolvimento de Software baseado em Software Livre. Para ilustrar as funcionalidades fornecidas pelo

Adailton Lima; Breno França; Heribert Schlebbe; Rodrigo Quites Reis; Carla Lima Reis

96

Thermal Structure and Para Hydrogen Fraction on the Outer Planets from VoyagerIRIS Measurements  

Microsoft Academic Search

Voyagerinfrared spectra from Jupiter, Saturn, Uranus, and Neptune are used to infer latitude-height cross sections of temperature and para hydrogen fraction. A new inversion algorithm is developed that simultaneously retrieves both quantities. It uses all portions of the spectra containing information about temperature and para fraction and not influenced by other properties, such as cloud opacity. The sensitivity of spectra

Barney J. Conrath; Peter J. Gierasch; Eugene A. Ustinov

1998-01-01

97

Sudan azo dyes and Para Red degradation by prevalent bacteria of the human gastrointestinal tract  

Microsoft Academic Search

Sudan azo dyes have genotoxic effects and ingestion of food products contaminated with Sudan I, II, III, IV, and Para Red could lead to exposure in the human gastrointestinal tract. In this study, we examined thirty-five prevalent species of human intestinal bacteria to evaluate their capacity to degrade Sudan dyes and Para Red. Among these tested bacterial strains, 23, 13,

Haiyan Xu; Thomas M. Heinze; Donald D. Paine; Carl E. Cerniglia; Huizhong Chen

2010-01-01

98

PERSPECTIVAS METODOLÓGICAS PARA LA INVESTIGACIÓN DENTRO DEL AULA DE L2  

Microsoft Academic Search

Dicen Larsen- Freeman y Long (1991) que las premisas básicas para un experimento son que todos los factores excepto uno sean constantes para poder comprobar el efecto de ese factor sobre el fenómeno que se inves- tiga, y que se cuente con dos criterios esenciales: primero, que haya al me- nos dos grupos incluidos en el estudio, uno de control

Guadalupe Ruiz Fajardo

1991-01-01

99

[The place of para-aortic lymphadenectomy in gynaecological malignancies. An old debate].  

PubMed

There is a lack of prospective randomized trial and scientific evidence for the use of para-aortic lymphadenectomy in gynaecological malignancies. This results in variations between countries for its utility. Based on the recommandations of the French Institute of Cancer (INCa), we open the debate of the place of para-aortic lymphadenectomy. PMID:24793624

Philippe, Anne-Cécile; Dauplat, Jacques; Martinez, Alejandra; Canis, Michel; Bourdel, Nicolas; Ferron, Gwenaël; Pomel, Christophe

2014-04-01

100

Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media  

DOEpatents

A method is disclosed for isolating and identifying modified para-nitrobenzyl esterases which exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase. 43 figs.

Arnold, F.H.; Moore, J.C.

1999-05-25

101

Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media  

DOEpatents

A method is disclosed for isolating and identifying modified para-nitrobenzyl esterases. These enzymes exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase. 43 figs.

Arnold, F.H.; Moore, J.C.

1998-04-21

102

Sudan azo dyes and Para Red degradation by prevalent bacteria of the human gastrointestinal tract.  

PubMed

Sudan azo dyes have genotoxic effects and ingestion of food products contaminated with Sudan I, II, III, IV, and Para Red could lead to exposure in the human gastrointestinal tract. In this study, we examined thirty-five prevalent species of human intestinal bacteria to evaluate their capacity to degrade Sudan dyes and Para Red. Among these tested bacterial strains, 23, 13, 33, 30, and 29 out of 35 species tested were able to reduce Sudan I, II, III, IV, and Para Red, respectively, to some extent. Bifidobacterium infantis, Clostridium indolis, Enterococcus faecalis, Lactobacillus rhamnosus, and Ruminococcus obeum were able to reduce completely all four tested Sudan dyes and Para Red. Escherichia coli and Peptostreptococcus magnus were the only two strains that were not able to reduce any of the tested Sudan dyes and Para Red to any significant extent. Metabolites of the reduction of the tested Sudan dyes and Para Red by E. faecalis were isolated and identified by HPLC and LC/ESI-MS analyses and compared with authentic standards. Thus it appears that the ability to reduce Sudan dyes and Para Red except Sudan II is common among bacteria in the human colon. PMID:19580882

Xu, Haiyan; Heinze, Thomas M; Paine, Donald D; Cerniglia, Carl E; Chen, Huizhong

2010-04-01

103

Um enfoque antropológico para o ensino de astronomia no nível médio  

NASA Astrophysics Data System (ADS)

Há uma enorme carência de materiais didático-pedagógicos em astronomia para professores do ensino médio, sobretudo materiais que explorem também aspectos humanísticos. A origem do Universo é um bom exemplo desta constatação central. Embora tal origem teve explicações culturais diversas, os professores não têm informações sobre isso e muito menos material que trabalhe diferentes visões de mundo e treinamento que os capacite a abordá-las devidamente. Conseqüentemente o ensino de astronomia costuma ser tecnicista e dissociado do aspecto humano que alimenta o grande interesse e curiosidade que esses temas despertam. Aqui apresentamos propostas visando contribuir para reverter esse quadro e trabalhamos distintas visões de Universo: espontâneas, autóctones e científicas. Desenvolvemos práticas, materiais instrucionais e textos para viabilizar a adoção de um enfoque antropológico para o ensino de astronomia no nível médio, no qual as culturas humanística e científica sejam integradas de uma maneira contextualizada e eficaz para aquele ensino. Estas propostas foram aplicadas em um curso de treinamento para professores da rede pública de diferentes disciplinas. A receptividade dos professores à abordagem proposta e os resultados alcançados foram muito estimulantes. Destes, destacamos: produção de roteiros de atividades; desenvolvimento de práticas didático-pedagógicas específicas (e.g., encenação de mitos; dança primordial guarani; "criação" de constelações e interpretações pluriculturais; etc.); e sugestões concretas para a efetiva realização de um ensino interdisciplinar contextualizado, onde questões cosmogônicas servem de mote para iniciar tal ensino. Discutimos estes resultados e como o enfoque adotado pode instrumentalizar os professores para leituras de mundo que incluem naturalmente aspectos culturais, sociais e históricos associados aos temas estudados. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

Costa, G. B.; Jafelice, L. C.

2003-08-01

104

CONSTRUIR SIGNIFICADOS AL EMPLEAR MAPAS CONCEPTUALES SOPORTADOS EN LAS TECNOLOGÍAS (To construct to meaning when using sopported conceptual maps in the technologies)  

Microsoft Academic Search

La propuesta expone implicaciones del empleo de mapas conceptuales para la elaboración de significados aplicando herramientas tecnológicas. El mapa conceptual es un instrumento para la organización y elaboración de significados en la matriz cognoscitiva. Hernández (2005), afirma que permite seleccionar estrategias, identificar concepciones y elaborar constructos. Asimismo, se muestra una reflexión a partir de experiencias con estudiantes universitarios en dos

Anny Castillo Rojas

2009-01-01

105

Descripción de la zona de alta difusión en un modelo bidimensional para hojas de corriente  

NASA Astrophysics Data System (ADS)

Los modelos bidimensionales para describir hojas de corriente de alta simetría no suministran una descripción detallada de las regiones donde la difusión es considerablemente importante. Tal es el caso de los modelos desarrollados en la década del '60 por Sweet, Parker, Petschek y Sonnerup. En esta comunicación presentamos una solución de las ecuaciones MHD en el entorno del origen, construyendo series bidimensionales para todas las magnitudes físicas involucradas. Valiéndonos de la alta simetría y de las características del problema, logramos reducir el número de coeficientes a calcular. Utilizamos un programa autoconsistente para extender el cálculo a regiones vecinas con difusión moderada o despreciable.

Montero, M. F.; Paola, C. A.; Platzeck, A. M.

106

Measurement of the formaldehyde ortho to para ratio in three molecular clouds  

NASA Technical Reports Server (NTRS)

Observations of ortho and para H2CO in two types of clouds, a warm cloud (Orion A) and two cold clouds (L183 and TMC1), are presented. The ortho to para ratio in Orion deduced from the H2(C-13)O data is about three, while that for TMC1 is about one and that for L183 is 1-2. The former value is in agreement with the value calculated from chemical models of ortho and para H2CO production. The values for the cold clouds are consistent with thermal equilibrium at a temperature slightly smaller than 10 K.

Kahane, C.; Lucas, R.; Frerking, M. A.; Langer, W. D.; Encrenaz, P.

1984-01-01

107

Triebel-Lizorkin Spaces of Para-Accretive Type and a  Tb Theorem  

Microsoft Academic Search

In this article, we use a discrete Calderón-type reproducing formula and Plancherel-Pôlya-type inequality associated to a\\u000a para-accretive function to characterize the Triebel-Lizorkin spaces of para-accretive type \\u000a \\u000a , which reduces to the classical Triebel-Lizorkin spaces when the para-accretive function is constant. Moreover, we give a\\u000a necessary and sufficient condition for the \\u000a \\u000a boundedness of paraproduct operators. From this, we show that a

Chin-Cheng Lin; Kunchuan Wang

2009-01-01

108

Endovascular Treatment of a Ruptured Para-Anastomotic Aneurysm of the Abdominal Aorta  

SciTech Connect

We report a case of a ruptured para-anastomotic aortic aneurysm treated with implantation of a bifurcated stent-graft. A 72-year-old patient, who had undergone aortobifemoral bypass for aortoiliac occlusive disease 16 years ago, presented with a ruptured para-anastomotic aortic aneurysm. A bifurcated stent-graft was successfully deployed into the old bifurcated graft. This is the first report of a bifurcated stent-graft being placed through an 'end-to-side' anastomosed old aortobifemoral graft. Endovascular treatment of ruptured para-anastomotic aortic aneurysms can be accomplished successfully, avoiding open surgery which is associated with increased mortality and morbidity.

Sfyroeras, Giorgos S.; Lioupis, Christos, E-mail: lioupisC@vodafone.net.gr; Bessias, Nikolaos; Maras, Dimitris [Red Cross Hospital of Athens, Department of Vascular Surgery (Greece); Pomoni, Maria [Red Cross Hospital of Athens, Department of Radiology (Greece); Andrikopoulos, Vassilios [Red Cross Hospital of Athens, Department of Vascular Surgery (Greece)

2008-07-15

109

Contextual Factors that Foster or Inhibit Para-Teacher Professional Development: The Case of an Indian, Non-Governmental Organization  

ERIC Educational Resources Information Center

The appointment of para-professionals to overcome skill shortages and/or make efficient use of expensive resources is well established in both developing and developed countries. The present research concerns para-teachers in India. The literature on para-teachers is dominated by training for special needs settings, largely in developed societies.…

Raval, Harini; McKenney, Susan; Pieters, Jules

2012-01-01

110

Investigation of para-sulfonatocalix[n]arenes [n = 6, 8] as potential chelates for (230)U.  

PubMed

Literature reports of the efficacy of para-sulfonatocalix[6]- and calix[8]-arenes as U(vi) complexants indicated that they might be useful for in vivo chelation of the novel therapeutic alpha-emitter (230)U. We have studied the complexation of U(vi) with para-sulfonatocalix[6]arene and para-sulfonatocalix[8]arene by time resolved laser induced fluorescence spectroscopy and using competition methods with Chelex resin and 4-(2-pyridylazo)resorcinol in simplified and in biological media. New thermodynamic parameters describing the stability of U(vi)-para-sulfonatocalix[n]arene [n = 6, 8] complexes were obtained. Although the interactions are strong, the complexes do not exhibit sufficient stability to compete with carbonate ions and serum proteins for complexation of U(vi) under physiological conditions. PMID:20104364

Montavon, Gilles; Repinc, Urska; Apostolidis, Christos; Bruchertseifer, Frank; Abbas, Kamel; Morgenstern, Alfred

2010-02-01

111

Potential Demand for Ecotourism in the Tapajos National Forest, Para, Brazil.  

National Technical Information Service (NTIS)

Sustainable forest management is a global issue of increasing importance. As part of an effort to evaluate sustainable forest management alternatives for the Tapajos National Forest (TNF) in Para, Brazil, IBAMA (The Brazilian Institute for Environment and...

1997-01-01

112

Cold-plasma assisted hydrophobisation of cellulose fibres with styrene and para-halogenated homologues  

NASA Astrophysics Data System (ADS)

Cold-plasma-assisted treatment of additive-free hand sheet paper samples with styrene (ST), para-fluorostyrene (FST), para-fluoro-?-methylstyrene (FMST) and para-chloro-?-methylstyrene (ClMST) and para-bromostyrene (BrST) was studied and found that the grafting has occurred efficiently, as established by contact angle measurement. Thus, after solvent extraction of the modified substrates, in order to remove unbounded grafts, the contact angle value of a drop of water deposited at the surface of paper increased from 40° for unmodified substrate to 102, 99, 116, 100 and 107°, for ST-, FST- FMST-, ClMST- and BrST-treated samples, respectively, indicating that the surface has became totally hydrophobic. In fact, the polar component of the surface energy of treated samples decreased from 25 mJ/m2 to practically zero, indicating that treated surfaces were rendered totally non polar.

Gaiolas, C.; Costa, A. P.; Santos Silva, M. J.; Belgacem, M. N.

2012-07-01

113

Contribuições para o projeto da câmara infravermelha Spartan do telescópio SOAR  

NASA Astrophysics Data System (ADS)

Como parte de uma colaboração entre a Divisão de Astrofísica do INPE, IAG-USP, Instituto do Milênio MEGALIT e a Michigan State University, trabalhamos durante um ano junto ao grupo do Dr. Edwin Loh (MSU) no projeto e detalhamento de diversos subsistemas para a câmara infravermelho Spartan do telescópio SOAR. Trata-se de um imageador para as bandas J, H e K que explora todo o potencial, em termos de qualidade de imagem e campo de visada, fornecido pelo sistema de óptica adaptativa de primeira ordem do telescópio SOAR. Projetamos soluções detalhadas para os subsistemas de rodas de filtros/grismas/máscaras de Lyot; subsistema de compactação do mosaico de detectores em duas versões distintas; subsistema de alimentação de Nitrogênio líquido. Mantivemos sempre uma supervisão geral sobre todas as partes restantes e os respectivos envelopes volumétricos produzindo soluções para a integração de todos os componentes. Neste trabalho, ilustramos as principais contribuições e fornecemos um resumo do estado atual do instrumento.

Laporte, R.; Jablonski, F.; Loh, E.

2003-08-01

114

Path Integral Monte Carlo Studies of molecular para-hydrogen clusters  

Microsoft Academic Search

Using the path integral Monte Carlo method, we have extensively studied para-hydrogen clusters, (pH_2)_N, with 6<= N <= 35 as a function of temperature. Small molecular para-hydrogen clusters are predicted to be superfluid at temperatures below about 2K. In view of recent experiments, we characterize the structual and energetic properties over the temperature range T = 1 - 10K using

Kwangsik Nho; Doerte Blume

2004-01-01

115

Thermal characterization of para- tert-butylphenol formaldehyde epoxy-acrylic resin cured with reactive diluents  

Microsoft Academic Search

The thermal decomposition of para-tert-butylphenol formaldehyde epoxy-acrylic resin as such or in the presence of reactive diluents based on glycidyl ethers of phenol and para-alkyl substituted phenols has been studied using pyrolysis in combination with gas chromatography and thermogravimetric techniques. The samples analysed in the range of temperatures between 200 and 600°C degrade statistically by a radical mechanism. The decomposition

C. N. Ca?caval; D. Ro?u; A. Stoleriu

2000-01-01

116

Observation of Ortho-Para H+3 Selection Rules in Plasma Chemistry  

NASA Astrophysics Data System (ADS)

Intensity ratios of infrared spectral lines of ortho- and para- H+3 have been measured in hydrogen plasmas using normal and para- H2. Large dependences of the intensity ratios on the parent gases have been observed, indicating the spin memory of protons even after chemical reactions. The results clearly demonstrate the existence of selection rules on nuclear spin modifications in chemical reactions theoretically anticipated by M. Quack [Mol. Phys. 34, 477 (1977)].

Uy, Dairene; Cordonnier, Michel; Oka, Takeshi

1997-05-01

117

Blurring the boundaries between professional and para-professional catalogers at California State University, Northridge  

Microsoft Academic Search

What used to be a clear-cut division between the duties of professional and para-professional catalogers has become blurred in many libraries. The authors will illustrate this point by discussing the evolution of responsibilities held by para-professional and professional catalogers over the course of a 10-year period in the Cataloging Department at California State University, Northridge (CSUN). Comparisons will be made

Jina Choi Wakimoto; Gina R Hsiung

2000-01-01

118

ParaDIS: A relational database for the consistent documentation and analysis of metamorphic mineral assemblages  

Microsoft Academic Search

A set of integrated computer programs has been developed to optimize documentation, storage, and analysis of petrological data. Primary petrographic and mineral chemistry data, as well as petrological results (such as stability diagrams) derived from these data, are documented by a relational database named ParaDIS (Paragenetic Data Inventory System).ParaDIS is implemented using INGRES™, a commercial relational database-management system running under

D. R. Schmatz; M. Engi; J. E. Lieberman

1995-01-01

119

Rhabdomyolysis and acute renal failure in a child with para-influenza type 1 infection  

Microsoft Academic Search

We present a rare case of para-influenza type 1 virus-induced rhabdomyolysis, complicated by acute renal failure (ARF). The\\u000a child underwent continuous venovenous haemofiltration and has shown full clinical and biochemical recovery. ARF due to rhabdomyolysis\\u000a in para-influenza type 1 infection in a child has, to the best of our knowledge, not been previously reported.

Renata Vrsalovic; Goran Tesovic; Branko Mise

2007-01-01

120

Synthesis and biological activity of Para-substituted 3?-phenyl docetaxel analogs  

Microsoft Academic Search

An expedient route for semisynthetic para-modified 3?-phenyl docetaxel analogs is described using the initial regioselective iodination of the oxazolidinecarboxylate 3. Palladium catalyzed coupling reactions of the iodo intermediate 4 with alkenyl and aryl boronic acids and alkynes led after alkaline hydrolysis to a series of N,O-protected para-substituted phenylisoserines 6. Coupling with 10-deacetyl-7, 10-O-diTroc-baccatin III followed by standard deprotections and acylation

Jean-Dominique Bourzat; François Lavelle; Alain Commerçon

1995-01-01

121

ParA ATPases can move and position DNA and subcellular structures.  

PubMed

Prokaryotic chromosomes and plasmids can be actively segregated by partitioning (par) loci. The common ParA-encoding par loci segregate plasmids by arranging them in regular arrays over the nucleoid by an unknown mechanism. Recent observations indicate that ParA moves plasmids and chromosomes by a pulling mechanism. Even though ParAs form filaments in vitro it is not known whether similar structures are present in vivo. ParA of P1 forms filaments in vitro at very high concentrations only and filament-like structures have not been observed in vivo. Consequently, a 'diffusion-ratchet' mechanism was suggested to explain plasmid movement by ParA of P1. We compare this mechanism with our previously proposed filament model for plasmid movement by ParA. Remarkably, ParA homologues have been discovered to arrange subcellular structures such as carboxysomes and chemotaxis sensory receptors in a regular manner very similar to those of the plasmid arrays. PMID:21963112

Szardenings, Florian; Guymer, David; Gerdes, Kenn

2011-12-01

122

Ghost loci imply Hox and ParaHox existence in the last common ancestor of animals.  

PubMed

Hox genes are renowned for patterning animal development, with widespread roles in developmental gene regulation. Despite this importance, their evolutionary origin remains obscure, due to absence of Hox genes (and their evolutionary sisters, the ParaHox genes) from basal lineages and because the phylogenies of these genes are poorly resolved. This has led to debate about whether Hox and ParaHox genes originated coincidently with the origin of animals or instead evolved after the divergence of the earliest animal lineages. Here we use genomic synteny and Monte Carlo-based simulations to resolve Hox/ParaHox origins, our approach being independent of poorly resolved homeodomain phylogenies and better able to accommodate gene loss. We show Trox-2 of placozoans occupies a ParaHox locus. In addition, a separate locus sharing synteny and hence homology with human Hox loci exists in the placozoan genome, but without a Hox-like gene in it. We call this second locus a "ghost" Hox locus, because it is homologous to the human Hox loci, but does not itself contain a Hox gene. Extending our approach to sponges, we discover distinct ghost Hox and ParaHox loci. Thus, distinct Hox and ParaHox loci were present in the last common ancestor of all living animal lineages. PMID:23022064

Mendivil Ramos, Olivia; Barker, Daniel; Ferrier, David E K

2012-10-23

123

Intensity-modulated Radiation Therapy Versus Para-aortic Field Radiotherapy to Treat Para-aortic Lymph Node Metastasis in Cervical Cancer: Prospective Study  

PubMed Central

Aim To compare dosimetry, efficacy, and toxicity of intensity-modulated radiation therapy (IMRT) with para-aortic field radiotherapy in patients with para-aortic lymph node (PALN) metastasis of cervical cancer. Methods This prospective study examined 60 patients with cervical cancer with PALN metastasis who underwent whole-pelvis radiotherapy followed by brachytherapy between November 1, 2004 and May 31, 2008. After 3 cycles of chemotherapy, patients were serially allocated into two groups and treated with IMRT or para-aortic field RT at doses of 58-68 Gy and 45-50 Gy, respectively. Treatment response was evaluated and toxicities were assessed. Patients in the IMRT group were treated with both para-aortic field RT and IMRT in order to compare the exposure dose of organs at risk. Results In the IMRT group, the mean dose delivered to the planning target volume was 67.5 Gy. At least 99% of the gross tumor volume received effective coverage and radical dose (median, 63.5 Gy; range, 54.5-66) during treatment. IMRT plans yielded better dose conformity to the target and better sparing of the spinal cord and small intestine than para-aortic field RT. The IMRT patients experienced less acute and chronic toxicities. The IMRT group also had higher 2- and 3-year survival rates than the para-aortic RT group (2-year, 58.8% vs 25.0%, P = 0.019; 3-year, 36.4% vs 15.6%, P = 0.016). However, no significant difference was found in 1-year survival (67.7% vs 51.3%, P =0.201). The median survival in the IMRT group was 25 months (range, 3 to 37 months). The actuarial overall survival, disease-free survival, and locoregional control rates at 2 years were 67%, 77%, and 88%, respectively. Conclusions IMRT provides better clinical outcomes than para-aortic field radiotherapy in patients with PALN metastasis. However, cervical local and distal recurrence remain a problem. Long-term follow-up and studies involving more patients are needed to confirm our results.

Du, Xue-lian; Sheng, Xiu-gui; Jiang, Tao; Yu, Hao; Yan, Yu-feng; Gao, Rong; Lu, Chun-hua; Li, Qing-shui

2010-01-01

124

Spontaneous Emission Between - and Para-Levels of Water-Ion H_2O^+  

NASA Astrophysics Data System (ADS)

Nuclear spin conversion interaction of water ion, H_2O^+, has been studied to derive spontaneous emission lifetime between ortho- and para-levels. H_2O^+ is a radical ion with the ^2B_1 electronic ground state. Its off-diagonal electron spin-nuclear spin interaction term, Tab(S_a? I_b + S_b? I_a), connects para and ortho levels, because ? I = I_1 - I_2 has nonvanishing matrix elements between I = 0 and 1. The mixing by this term with Tab = 72 MHz predicted by ab initio theory in the MRD-CI/Bk level, is many orders of magnitude larger than for closed shell molecules because of the large magnetic interaction due to the un-paired electron. Using the molecular constants reported by Mürtz et al. by FIR-LMR, we searched for ortho and para coupling channels below 1000 cm-1 with accidental near degeneracy between para and ortho levels. For example, hyperfine components of the 42,2(ortho) and 33,0(para) levels mix by 1.2 × 10-3 due to their near degeneracy (? E = 0.417 cm-1), and give the ortho-para spontaneous emission lifetime of about 0.63 year. The most significant low lying 10,1(para) and 11,1(ortho) levels, on the contrary, mix only by 8.7 × 10-5 because of their large separation (? E = 16.267 cm-1) and give the spontaneous emission lifetime from 10,1(para) to 00,0(ortho) of about 100 year.These results qualitatively help to understand the observed high ortho- to para- H_2O^+ ratio of 4.8 ± 0.5 toward Sgr B2 but they are too slow to compete with the conversion by collision unless the number density of the region is very low (n ˜1 cm-3) or radiative temperature is very high (T_r > 100 K). M. Staikova, B. Engels, M. Peric, and S.D. Peyerimhoff, Mol. Phys. 80, 1485 (1993) P. Mürtz, L.R. Zink, K.M. Evenson, and J.M. Brown J. Chem. Phys. 109, 9744 (1998). LP. Schilke, et al., A&A 521, L11 (2010).

Tanaka, Keiichi; Harada, Kensuke; Nanbu, Shinkoh; Oka, Takeshi

2012-06-01

125

The Formaldehyde Ortho/Para Ratio as a Probe of Dark Cloud Chemistry and Evolution  

NASA Astrophysics Data System (ADS)

We present measurements of the H2CO ortho/para ratio toward four star-forming cores, L723, L1228, L1527, and L43, and one quiescent core, L1498. Combining these data with earlier results by Minh et al., three quiescent cores are found to have ortho/para ratios near 3, the ratio of statistical weights expected for gas-phase formation processes. In contrast, ortho/para ratios are 1.5-2.1 in five star-forming cores, suggesting thermalization at a kinetic temperature of 10 K. We attribute modification of the ortho/para ratio in the latter cores to formation and/or equilibration of H2CO on grains with subsequent release back into the gas phase due to the increased energy inputs from the forming star and outflow. We see accompanying enhancements in the H2CO abundance relative to H2 to support this idea. The results suggest that the formaldehyde ortho/para ratio can differentiate between quiescent cores and those in which low-mass star formation has occurred.

Dickens, J. E.; Irvine, W. M.

1999-06-01

126

ParaPep: a web resource for experimentally validated antiparasitic peptide sequences and their structures.  

PubMed

ParaPep is a repository of antiparasitic peptides, which provides comprehensive information related to experimentally validated antiparasitic peptide sequences and their structures. The data were collected and compiled from published research papers, patents and from various databases. The current release of ParaPep holds 863 entries among which 519 are unique peptides. In addition to peptides having natural amino acids, ParaPep also consists of peptides having d-amino acids and chemically modified residues. In ParaPep, most of the peptides have been evaluated for growth inhibition of various species of Plasmodium, Leishmania and Trypanosoma. We have provided comprehensive information about these peptides that include peptide sequence, chemical modifications, stereochemistry, antiparasitic activity, origin, nature of peptide, assay types, type of parasite, mode of action and hemolytic activity. Structures of peptides consisting of natural, as well as modified amino acids have been determined using state-of-the-art software, PEPstr. To facilitate users, various user-friendly web tools, for data fetching, analysis and browsing, have been integrated. We hope that ParaPep will be advantageous in designing therapeutic peptides against parasitic diseases. Database URL: http://crdd.osdd.net/raghava/parapep/ PMID:24923818

Mehta, Divya; Anand, Priya; Kumar, Vineet; Joshi, Anshika; Mathur, Deepika; Singh, Sandeep; Tuknait, Abhishek; Chaudhary, Kumardeep; Gautam, Shailendra K; Gautam, Ankur; Varshney, Grish C; Raghava, Gajendra P S

2014-01-01

127

The formaldehyde ortho/para ratio as a probe of dark cloud chemistry and evolution  

NASA Technical Reports Server (NTRS)

We present measurements of the H2CO ortho/para ratio toward four star-forming cores, L723, L1228, L1527, and L43, and one quiescent core, L1498. Combining these data with earlier results by Minh et al., three quiescent cores are found to have ortho/para ratios near 3, the ratio of statistical weights expected for gas-phase formation processes. In contrast, ortho/para ratios are 1.5-2.1 in five star-forming cores, suggesting thermalization at a kinetic temperature of 10 K. We attribute modification of the ortho/para ratio in the latter cores to formation and/or equilibration of H2CO on grains with sub-sequent release back into the gas phase due to the increased energy inputs from the forming star and outflow. We see accompanying enhancements in the H2CO abundance relative to H, to support this idea. The results suggest that the formaldehyde ortho/para ratio can differentiate between quiescent cores and those in which low-mass star formation has occurred.

Dickens, J. E.; Irvine, W. M.

1999-01-01

128

Rotational excitation of HCN by para- and ortho-H2.  

PubMed

Rotational excitation of the hydrogen cyanide (HCN) molecule by collisions with para-H2(?j = 0,?2) and ortho-H2(?j = 1) is investigated at low temperatures using a quantum time independent approach. Both molecules are treated as rigid rotors. The scattering calculations are based on a highly correlated ab initio 4-dimensional (4D) potential energy surface recently published. Rotationally inelastic cross sections among the 13 first rotational levels of HCN were obtained using a pure quantum close coupling approach for total energies up to 1200 cm(-1). The corresponding thermal rate coefficients were computed for temperatures ranging from 5 to 100 K. The HCN rate coefficients are strongly dependent on the rotational level of the H2 molecule. In particular, the rate coefficients for collisions with para-H2(?j = 0) are significantly lower than those for collisions with ortho-H2(?j = 1) and para-H2(?j = 2). Propensity rules in favor of even ?j transitions were found for HCN in collisions with para-H2(?j = 0) whereas propensity rules in favor of odd ?j transitions were found for HCN in collisions with H2(?j ? 1). The new rate coefficients were compared with previously published HCN-para-H2(?j = 0) rate coefficients. Significant differences were found due the inclusion of the H2 rotational structure in the scattering calculations. These new rate coefficients will be crucial to improve the estimation of the HCN abundance in the interstellar medium. PMID:24929383

Vera, Mario Hernández; Kalugina, Yulia; Denis-Alpizar, Otoniel; Stoecklin, Thierry; Lique, François

2014-06-14

129

ParaDIS: A relational database for the consistent documentation and analysis of metamorphic mineral assemblages  

NASA Astrophysics Data System (ADS)

A set of integrated computer programs has been developed to optimize documentation, storage, and analysis of petrological data. Primary petrographic and mineral chemistry data, as well as petrological results (such as stability diagrams) derived from these data, are documented by a relational database named ParaDIS (Paragenetic Data Inventory System). ParaDIS is implemented using INGRES ™, a commercial relational database-management system running under UNIX on Sun computers. Two user-friendly applications, forms-based and menu-operated, allow for entry, retrieval, and various manipulations of any amount of petrological data. In the current version, ParaDIS is interfaced with external thermobarometric programs (e.g. TWEEQU, PTAX) based on consistent thermodynamic models, allowing for coherent interpretation of metamorphic assemblages. The results (e.g. P-T- or T-X-graphs) can be directed back into ParaDIS for further analysis and to document the interpretations. P-T-data derived for particular field areas also can be fed into graphics programs or Geographical Information Systems (GIS) for further manipulation, such as P-T-contouring, and display. Data architecture and storage structure of ParaDIS are presented in detail.

Schmatz, D. R.; Engi, M.; Lieberman, J. E.

1995-11-01

130

Estimation of Carbon Storage in Para Rubber Plantation in Eastern Thailand  

NASA Astrophysics Data System (ADS)

This study aims to estimate the carbon stock and sequestration in Para rubber plantation of East Thailand using the THAICHOTE (Thailand Earth Observation System data). For that purpose we identify the area of every stage class Para rubber plantation by the analysis of different image objects (i.e., rule base and multiple regression classifications) and we map the carbon stock and sequestration of each Para rubber class using biomass allometric regressions and carbon content equations. THAICHOTE data include Multispectral image (4 bands at 15x15 m spatial resolution), Panchromatic image (2x2 m spatial resolution) and Stereo image, data acquisition from December 2011-April 2012. The preliminary investigated area is located in Wangchun, (Eastern, Thailand) and covers about 20 Km2. Calibrating the class stage, by image analysis that integrated edge-based segmentation, reflectance, remote sensing indices, texture analysis and canopy height model (CHM), we found that best classification was obtained by multiple regression (accuracy of 80%) compared to rule base logical operation (accuracy 70%) suggesting that manual 3D stereo measurements or Light Detection And Ranging (LiDAR) both are able to construct the CHM. The results of this study indicate that for a total Para rubber biomass of 14,651 tons, the amount of stored carbon is of 7,326 tons. Mature stage of Para rubber plantations exhibits the highest capacity of sequestering with a global flux of 0.21 tons C/ Km2/year.

Charoenjit, K.; Zuddas, P.; Allemand, P.

2012-12-01

131

ParaPep: a web resource for experimentally validated antiparasitic peptide sequences and their structures  

PubMed Central

ParaPep is a repository of antiparasitic peptides, which provides comprehensive information related to experimentally validated antiparasitic peptide sequences and their structures. The data were collected and compiled from published research papers, patents and from various databases. The current release of ParaPep holds 863 entries among which 519 are unique peptides. In addition to peptides having natural amino acids, ParaPep also consists of peptides having d-amino acids and chemically modified residues. In ParaPep, most of the peptides have been evaluated for growth inhibition of various species of Plasmodium, Leishmania and Trypanosoma. We have provided comprehensive information about these peptides that include peptide sequence, chemical modifications, stereochemistry, antiparasitic activity, origin, nature of peptide, assay types, type of parasite, mode of action and hemolytic activity. Structures of peptides consisting of natural, as well as modified amino acids have been determined using state-of-the-art software, PEPstr. To facilitate users, various user-friendly web tools, for data fetching, analysis and browsing, have been integrated. We hope that ParaPep will be advantageous in designing therapeutic peptides against parasitic diseases. Database URL: http://crdd.osdd.net/raghava/parapep/

Mehta, Divya; Anand, Priya; Kumar, Vineet; Joshi, Anshika; Mathur, Deepika; Singh, Sandeep; Tuknait, Abhishek; Chaudhary, Kumardeep; Gautam, Shailendra K.; Gautam, Ankur; Varshney, Grish C.; Raghava, Gajendra P.S.

2014-01-01

132

Identification and Characterization of Catabolic para-Nitrophenol 4Monooxygenase and para-Benzoquinone Reductase from Pseudomonas sp. Strain WBC3  

Microsoft Academic Search

Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen, and energy. In order to identify the genes involved in this utilization, we cloned and sequenced a 12.7-kb fragment containing a conserved region of NAD(P)H:quinone oxidoreductase genes. Of the products of the 13 open reading frames deduced from this fragment, PnpA shares 24% identity to the

Jun-Jie Zhang; Hong Liu; Yi Xiao; Xian-En Zhang; Ning-Yi Zhou

2009-01-01

133

MODELO MATEMÁTICO PARA ESTIMAR EL ESPACIAMIENTO ENTRE DRENES SUBTERRÁNEOS EN RÉGIMEN TRANSITORIO Mathematical Model for Estimating Spacing Between Subterranean Drains in Transitory Regime  

Microsoft Academic Search

Para el diseño de sistemas de drenaje subterráneo existen diferentes modelos, tanto para régimen permanente, como transitorio; sin embargo, la mayoría de ellos no se han obtenido para condiciones de suelo y clima semiáridas. Por lo tanto, este trabajo tuvo como objetivo desarrollar una ecuación empírica para régimen transitorio que permitiera determinar el espaciamiento entre drenes paralelos, considerando los intervalos

Pablo Miguel Coras-Merino

2006-01-01

134

Ortho-para-H2 conversion by hydrogen exchange: Comparison of theory and experiment  

NASA Astrophysics Data System (ADS)

We report fully-quantum time-independent calculations of cross sections and rate coefficients for the collisional (de)excitation of H2 by H. Our calculations are based on the H3 global potential energy surface of Mielke et al. [J. Chem. Phys. 116, 4142 (2002)]. The reactive hydrogen exchange channels are taken into account. We show that the ortho-para and para-ortho conversion of H2 are significant processes at temperatures above ~300 K and for the last process we provide the first comparison with available experimental rate coefficients between 300 and 444 K. The good agreement between theory and experiment is a new illustration of our detailed understanding of the simplest chemical reaction. The importance of the ortho-para-H2 conversion by hydrogen exchange in astrophysics is discussed.

Lique, François; Honvault, Pascal; Faure, Alexandre

2012-10-01

135

Irritant contact dermatitis from a black henna tattoo without sensitization to para-phenylendiamine.  

PubMed

Allergic contact dermatitis from nonpermanent black henna tattoos has been frequently reported, particularly in children. Contamination or adulteration of the dyes with para-phenylendiamine has been identified as major cause of active sensitization and elicitation of severe allergic contact dermatitis. Sequelae include permanent sensitization, hyper- or hypopigmentation, scarring, keloids, and hypertrichosis. We report a rare case of irritant dermatitis to an unknown ingredient in a black henna tattoo with consecutive hypopigmentation. Sensitization to para-phenylendiamine and other para-compounds was excluded by patch test evaluation. This is relevant for future exposure to consumer products such as hair dyes or in occupational settings. Generally, black henna tattoos, particularly if done with dyes of unknown composition, should be strongly discouraged. PMID:23690526

Kind, Fabiola; Hofmeier, Kathrin Scherer; Bircher, Andreas J

2013-06-01

136

Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature  

NASA Astrophysics Data System (ADS)

Terahertz time-domain spectroscopy has been used to measure the absorption of water vapor in 0.2-2.4 THz range from low to high humidity at room temperature. The observed absorption lines are due to the water molecular rotations in the ground vibrational state. We find that the absorption strength of para transitions increases as humidity increases, while the absorption strength of ortho transitions increases and then decreases in intensity with increasing humidity. We explain this difference based on the nuclear spin statistics based ratio of ortho to para water monomer populations at room temperature. The preferential adsorption on the solid surfaces of para water leads to an ortho dominated vapor cloud whose monomer rotational absorption intensity decreases due to the effects of dimerization, molecular collisions, clustering, and interactions with liquid droplets at high concentrations.

Xin, X.; Altan, H.; Saint, A.; Matten, D.; Alfano, R. R.

2006-11-01

137

Superfluid Effects in PARA-H_2 Clusters Probed by CO_2 Rotation-Vibration Transitions  

NASA Astrophysics Data System (ADS)

The prospect of directly observing superfluidity in para-H_2 is a tantalizing but elusive goal. Like ^4He, para-H_2 is a light zero-spin boson. However, H_2-H_2 intermolecular interactions, though weak, are stronger than He-He interactions, and hydrogen is a solid below about 14 K. This makes detection of superfluidity in bulk hydrogen problematical, to say the least. But there are still possibilities for para-H_2 in the form of clusters or in nano-confined environments, and superfluid transition temperatures as high as ˜6 K have been predicted. Spectroscopic observations of (para-H_2)_N-CO_2 clusters were at first very difficult to interpret for N > 5. However, with the help of path integral Monte Carlo simulations and an accurate new H_2-CO_2 intermolecular potential surface which explicitly incorporates dependence on the CO_2 ?b{3} asymmetric stretch, it is now possible to achieve a remarkably consistent picture of (para-H_2)_N-CO_2 clusters in the size range N = 1 ˜ 20. By combining the experimental spectroscopic measurements and theoretical simulations, we determine the size evolution of the superfluid response of the CO_2-doped para-H_2 clusters, which peaks for the "magic" number N = 12. V. L. Ginzburg and A. A. Sobyanin, JETP Lett. 15, 343 (1972). A. R. W. McKellar, Paper WH04, 63rd OSU International Symposium on Molecular Spectroscopy, June 16-20, 2008. H. Li, P.-N. Roy, and R. J. Le Roy, J. Chem. Phys., submitted.

Li, Hui; Le Roy, Robert J.; Roy, Pierre-Nicholas; McKellar, A. R. W.

2010-06-01

138

Um supressor de fundo térmico para a câmara infravermelha CamIV  

NASA Astrophysics Data System (ADS)

O ângulo sólido subtendido pelos pixels na câmara infravermelha do NexGal (CamIV) que operamos no OPD/LNA contém contribuições provenientes do sistema de coleta de fluxo propriamente dito - sendo esta a parte que interessa para as medidas astronômicas - e contribuições da obstrução central, sistema de suporte do espelho secundário e região exterior à pupila de entrada do telescópio. Estas últimas contribuições são devi-das à emissão de corpo negro à temperatura ambiente e aumentam exponencialmente para comprimentos de onda maiores que 2 micra (banda K, no infravermelho próximo). Embora a resultante pode ser quantificada e subtraída dos sinais relevantes, sua variância se adiciona à variância do sinal, e pode ser facilmente a contribuição domi-nante para a incerteza final das medidas, tornando ineficiente o processo de extração de informação e degradando a sensibilidade da câmara. A maneira clássica de resolver esse problema em sistemas ópticos que operam no infravermelho, onde os efeitos da emissão térmica do ambiente são importantes, é restringir o ângulo sólido subtendido pelos pixels individuais exclusivamente aos raios provenientes do sistema óptico. Para tanto, projeta-se uma imagem real, bastante reduzida, da pupila de entrada do sistema óptico num anteparo que transmita para o sistema de imageamento só o que interessa, bloqueando as contribuições das bordas externas à pupila de entrada, obstrução central do telescópio e sistema de suporte. Como a projeção é realizada em ambiente criogênico, a contribuição térmica espúria é efetivamente eliminada. Nós optamos por um sistema do tipo Offner para implementar na prática esta função. Trata-se de um sistema baseado em espelhos esféricos, bastante compacto e ajustado por construção. A opção por espelhos do mesmo material que o sistema de suporte (Alumínio) minimiza a dilatação diferencial, crítica nesse tipo de aplicação. Apresentamos as soluções detalhadas do projeto óptico-mecânico, bem como uma análise de flexões e desempenho em termos de qualidade de imagem.

Jablonski, F.; Laporte, R.

2003-08-01

139

Large scale visualization on the Cray XT3 using ParaView.  

SciTech Connect

Post-processing and visualization are key components to understanding any simulation. Porting ParaView, a scalable visualization tool, to the Cray XT3 allows our analysts to leverage the same supercomputer they use for simulation to perform post-processing. Visualization tools traditionally rely on a variety of rendering, scripting, and networking resources; the challenge of running ParaView on the Lightweight Kernel is to provide and use the visualization and post-processing features in the absence of many OS resources. We have successfully accomplished this at Sandia National Laboratories and the Pittsburgh Supercomputing Center.

Rogers, David; Geveci, Berk (Kitware, Inc.); Eschenbert, Kent (Pittsburgh Supercomputing Center); Neundorf, Alexander (Technical University of Kaiserslautern); Marion, Patrick (Kitware, Inc.); Moreland, Kenneth D.; Greenfield, John

2008-05-01

140

Development of polymorphic microsatellite markers for the livebearing fish Poecilia parae.  

PubMed

We developed 16 novel polymorphic tetranucleotide microsatellite markers for Poecilia parae, a livebearing fish used in evolutionary studies because of its Y-linked colour and size polymorphism. A set of 199 clones was sequenced out of an enriched genomic library, and we achieved an enrichment efficiency of nearly 80%. Primers were designed for 16 pure repeats, and 59 P. parae were screened for polymorphism. Cross-amplification was tested on Poecilia picta and Poecilia reticulata, the guppy. The new microsatellite markers showed an exceptionally high allelic diversity and low stutter formation, proving their suitability for a broad range of applications in these species. PMID:21585912

Nater, Alexander; Krützen, Michael; Lindholm, Anna K

2008-07-01

141

Quantum rotation of ortho and para-water encapsulated in a fullerene cage  

PubMed Central

Inelastic neutron scattering, far-infrared spectroscopy, and cryogenic nuclear magnetic resonance are used to investigate the quantized rotation and ortho–para conversion of single water molecules trapped inside closed fullerene cages. The existence of metastable ortho-water molecules is demonstrated, and the interconversion of ortho-and para-water spin isomers is tracked in real time. Our investigation reveals that the ground state of encapsulated ortho water has a lifted degeneracy, associated with symmetry-breaking of the water environment.

Beduz, Carlo; Carravetta, Marina; Chen, Judy Y.-C.; Concistre, Maria; Denning, Mark; Frunzi, Michael; Horsewill, Anthony J.; Johannessen, Ole G.; Lawler, Ronald; Lei, Xuegong; Levitt, Malcolm H.; Li, Yongjun; Mamone, Salvatore; Murata, Yasujiro; Nagel, Urmas; Nishida, Tomoko; Ollivier, Jacques; Rols, Stephane; Room, Toomas; Sarkar, Riddhiman; Turro, Nicholas J.; Yang, Yifeng

2012-01-01

142

An excellent Pd-based nanocomposite catalyst for the selective hydrogenation of para-chloronitrobenzene  

Microsoft Academic Search

A partially reduced Pd\\/?-Fe2O3 nanocomposite catalyst (Pd\\/?-Fe2O3-PR) was prepared using PdO and ferric hydroxide colloidal particles as starting materials. This catalyst exhibited excellent catalytic properties for the selective hydrogenation of para-chloronitrobenzene (p-CNB) to para-chloroaniline (p-CAN). The selectivity to p-CAN reached 99.2% at complete conversion of the substrate and intermediates, and the hydrodechlorination of p-CAN was fully suppressed over Pd\\/?-Fe2O3-PR. The

Hongquan Liu; Minghui Liang; Chao Xiao; Ning Zheng; Xuhui Feng; Yan Liu; Jinglin Xie; Yuan Wang

2009-01-01

143

Performance characteristics of magnesium/para-nitrophenol cells in 2:1 magnesium electrolytes  

SciTech Connect

1 V/1 Ah magnesium/para-nitrophenol (PNP) reserve cells were fabricated and their performance was evaluated in different electrolytes [2M aqueous solutions of Mg(C1O[sub 4])[sub 2], MgCl[sub 2], and MgBr[sub 2

Kumar, G.; Sivashanugam, A.; Sridharan, R. (Central Electrochemical Research Inst., Karaikudi (India))

1993-11-01

144

EMPLEO DE FRACCIONES CELULARES DE LA LEVADURA Saccharomyces cerevisiae COMO ADITIVO ALIMENTARIO PARA Artemia franciscana  

Microsoft Academic Search

RESUMEN En el presente estudio se evalúa la levadura Saccharomyces cerevisiae de forma desintegrada (LD) y tres fracciones celulares obtenidas de ella: complejo pared-membrana (FP), núcleo-proteínas (FN) y citoplasma (FC) como aditivo alimentario utilizando al crustáceo Artemia franciscana como modelo de experimentación. Se realizaron dos bioensayos para determinar el efecto que ejercían dichos aditivos en el crecimiento, biomasa seca, supervivencia

Yamilé Comabella; Tsai García-Galano; Olimpia Carrillo; Yadir Mauri

145

Cuadro de mando y sistemas de información: herramientas estratégicas para la gestión medioambiental corporativa  

Microsoft Academic Search

En la actualidad protección del ambiente es un nuevo e importante objetivo estratégico de las empresas cubanas y del mundo. La información medioambiental se vuelve cada vez más relevante para las decisiones económicas, por lo que es necesario manejarla de manera oportuna. Muchas entidades presentan Sistemas de Gestión Medioambientales según NC ISO 14000 que se quedan en fases meramente declarativas

Frank Medel; Lourdes García; Liesby Gómez; Rebeca Pentón

2011-01-01

146

A Compendium of Provisions for a Model Ordinance for the Regulation of Public Para-Transit.  

National Technical Information Service (NTIS)

This report comprises a complete set of provisions for the regulation of various types of public para-transit transportation. Its preparation consisted for five stages: Collection and analysis of the statutes of every state, the ordinances of some 600 mun...

R. E. Samuels

1976-01-01

147

LIBROS DE MÚSICA PARA EL NUEVO MUNDO EN EL SIGLO XVI  

Microsoft Academic Search

En el Archivo General de Indias de Sevilla se conserva el expediente de un pleito que enfrentó a Alonso Pérez, copista y clérigo de Medina del Campo, y a Francisco Fernández de Córdoba, conocido impresor de Valladolid, en activo entre 1541 y 1570. Cada uno de los litigantes pretendía los derechos de publicación de los cantorales para las Indias, en

Emilio Ros-Fábregas

2001-01-01

148

Computer-controlled radiation therapy machine for pelvic and para-aortic nodal areas  

Microsoft Academic Search

A computer-controlled radiation therapy technique has been developed to treat cancer of the uterine cervix that has extended to the pelvic and para-aortic lymph nodes. During five longitudinal scans with a 4 cm wide 8 MV X ray beam, conformation of the high dose region to the target volume was achieved primarily by varying the other field dimensions. Treatment planning

Lee M. Chin; Peter K. Kijewski; Göran K. Svensson; John T. Chaffey; Martin B. Levene; B. E. Bjaerngard

1981-01-01

149

Factor Structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA)  

Microsoft Academic Search

The current concept and measures of self-efficacy for depression in adolescents do not consider developmental and cultural aspects essential to understand and assess this construct in Latino youth. We examined the factor structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA), a Spanish instrument designed to assess this construct as experienced by this population. Participants were 116

Mirella Díaz-Santos; Eduardo Cumba-Avilés; Guillermo Bernal; Carmen Rivera-Medina

2011-01-01

150

Hacia un framework Orientado a Objetos para Bills of Materials Complejos  

Microsoft Academic Search

Las empresas de producción industrial se enfrentan por un lado, a los cambios constantes de las condiciones del mercado, como po r ejemplo, los patrones de demanda, ciclo de vida de los productos mucho más cortos, etc. Por otro, a un mercado global, que requiere que la cadena de suministros, alcance muy altos niveles de eficiencia. Para mantener la competitividad

Marcela Vegetti; Gabriela Henning; Horacio Leone

151

Un Juego de Gravedad con Reconocimiento de Voz para Niños con Problemas de Lenguaje  

Microsoft Academic Search

En este trabajo presentamos un juego electrónico (Gravedad) con reconocimiento de voz para estimular a niños en edad escolar con problemas del lenguaje dislalia. Se presenta las características y elementos del juego electrónico, así como su integración con el sistema de reconocimiento de voz y los resultados de unas pruebas de usabilidad. El juego de Gravedad se desarrolló utilizando el

Carlos Miranda-Palm; Reyna Camal-U; José Cen-Magaña; Cinhtia Gonzalez-Segura; Sergio Gonzalez-Segura; Michel García; Lizzie Narvaez-Díaz

152

Estados Unidos y cuatro países de América Latina se unen para combatir el cáncer  

Cancer.gov

El Instituto Nacional del Cáncer (NCI) de Estados Unidos formalizó esta semana alianzas bilaterales con los gobiernos de Argentina, Brasil, México y Uruguay, para acelerar el avance contra el cáncer en la población hispana de Estados Unidos y de América Latina y mejorar la investigación del cáncer.

153

Aprovechamiento de los mercados financieros internacionales para gestionar el riesgo de amenazas naturales en América Latina  

Microsoft Academic Search

El presente informe técnico analiza la potencial aplicación práctica de los instrumentos financieros diseñados para el financiamiento y la transferencia del riesgo de las amenazas naturales en América Latina. En primer lugar, se presenta, en términos generales, el papel del financiamiento y de la transferencia de los riesgos en la gestión del riesgo de desastres. Luego se analiza las fuentes

Ivar Pettersen; John Magne Skjelvik; Nils Atle Krokeide

2006-01-01

154

Caracterización del mercado de energía elétrica para usuarios no regulados en Colombia  

Microsoft Academic Search

En este artículo se presenta un análisis sobre las características del mercado de energía para usuarios no regulados en Colombia, el cual puede ser considerado como un sub-mercado dentro del mercado global de energía eléctrica en Colombia. En este análisis se incluye un indicador de concentración de mercado (Herfindahl-Hirschman), así como los porcentajes de participación en cubrimiento de demanda y

Ana Cecilia Escudero; Sergio Botero Botero

2006-01-01

155

Sindicalismo docente, gobiernos y reformas educativas en América Latina y el Caribe: Condiciones para el diálogo  

Microsoft Academic Search

Este documento fue comisionado por la Red de Educación del Diálogo Regional de Política para la 9a Reunión Hemisférica celebrada entre los días 8 y 10 de noviembre de 2006. El trabajo está dividido en cuatro partes: se presenta una breve y esquemática caracterización del contexto y de las reformas educativas; se desarrolla un panorama general de las características de

Mariano Palamidessi; Martín Legarralde

2006-01-01

156

GOBIERNO ELECTRÓNICO: FASES, DIMENSIONES Y ALGUNAS CONSIDERACIONES A TENER EN CUENTA PARA SU IMPLEMENTACIÓN  

Microsoft Academic Search

El uso de las TIC cambia radicalmente la forma en que los gobiernos administran y ejecutan sus procesos internos, y abre la posibilidad de mejorar e incrementar los canales de comunicación con los ciudadanos. Así, el gobierno electrónico se observa como un medio para que los gobiernos modernicen sus procesos, mejoren sus interacciones con los ciudadanos y disminuyan la fractura

Roberto de Armas Urquiza; Alejandro de Armas Suárez

2011-01-01

157

EL TLC CA-EE.UU.: ¿Una Oportunidad de Crecimiento para los Paises Centroamericanos¿  

Microsoft Academic Search

Esta presentación fue comisionado por la Red de Integración y Comercio del Diálogo Regional de Política para la V Reunión Hemisférica celebrada los días 14 y 15 de agosto de 2003. Antecedentes Motivos y Razones de la Negociación Objetivos Generales de la Negociación Características y Estructura de la Negociación Contenido del TLC Agenda Integral de Cooperación Avances de la negociación

Gabriela Llobet

2003-01-01

158

Carencia de hierro en la infancia: Causas y consecuencias para el desarrollo infantil  

Microsoft Academic Search

ResumenSe comentan brevemente las causas principales de la carencia de hierro (CH), seguido de un examen de los estudios sobre la CH y el desarrollo y comportamiento cognitivos y motores del niño para probar un vínculo causal, clasificando dichos estudios por su diseño. La anemia por carencia de hierro (ACH) se asocia a numerosos inconvenientes psicosociales y económicos que pueden

Sally Grantham-McGregor; Helen Baker-Henningham

2010-01-01

159

La actuación pública para el fomento de nuevas empresas Hacia un enfoque de política económica  

Microsoft Academic Search

A lo largo de este trabajo abordaremos la tarea de analizar el perfil de las distintas actuaciones y la potencial existencia de una política econó- mica específica de creación de empresas, tras lo que trataremos de esta- blecer, en su caso, una posible estructura de la misma. Para alcanzar sen- dos propósitos intentaremos: revisar las líneas generales de los diferentes

José Antonio; Belso Martínez

160

30 anos de investigação sobre externalidades do IDE para as empresas nacionais: que conclusões?  

Microsoft Academic Search

Resumo: Durante as últimas três décadas, surgiu uma vasta literatura sobre a existência potencial de externalidades do IDE para as empresas domésticas traduzidas em ganhos de produtividade. Esta ocorrência relaciona-se com o facto de as empresas multinacionais possuírem activos intangíveis que podem ser transmitidos às empresas domésticas. A análise empírica não dá, contudo, indicações claras sobre o fenómeno. Neste artigo,

Nuno Crespo; Maria Paula Fontoura

2007-01-01

161

Sugestões para o uso do mini-exame do estado mental no Brasil  

Microsoft Academic Search

RESUMO - Modificações no mini-exame do estado mental (MEM) foram sugeridas anteriormente em nosso meio. Neste artigo relatamos sugestões para aplicação uniforme deste instrumento. Método: Avaliamos 433 indivíduos saudáveis sem queixas de memória através do MEM tendo seu desempenho sido avaliado quanto às variáveis demográficas. As modificações propostas foram detalhadamente descritas. Resultados: A escolaridade foi o principal fator que influenciou

Sonia M. D. Brucki; Ricardo Nitrini; Paulo Caramelli; Paulo H. F. Bertolucci; Ivan H. Okamoto

2003-01-01

162

SISTEMA REMOTO DE ADQUISICIÓN PARA EL CONTROL DEL RUIDO AMBIENTAL CON FPGA Y FPAA  

Microsoft Academic Search

RESUMEN Este artículo propone el diseño de un sistema de adquisición de datos con componentes digitales y analógicos microelectrónicos reconfigurables, como son el FPGA (Field Programmable Gate Array) y el FPAA (Field Programmable Analog Array), para monitorear y analizar la contaminación por ruido ambiental. Este prototipo obtiene los datos del ruido de una zona vial (zona centro de una ciudad)

A. Castillo Atoche; J. Vázquez Castillo; V. Sanchez Huerta; P. Del Río Dawn

163

Nivelación interterritorial e ineficiencia de las decisiones presupuestarias: reflexiones para el caso español  

Microsoft Academic Search

En este trabajo se estudian los efectos negativos de los esquemas de nivelación horizontal sobre la eficiencia en las elecciones fiscales de los gobiernos regionales. Partiendo de unos resultados teóricos básicos, se examinan los aspectos dinámicos del problema, se ofrece alguna evidencia empírica para el caso español y se presenta una solución que combina los criterios de eficiencia y equidad.

Santiago Lago Peñas

2002-01-01

164

LA ENERGÍA EN LA FORMACIÓN DE LOS SUELOS: ASPECTOS TEÓRICOS Y METODOLÓGICOS PARA SU EVALUACIÓN  

Microsoft Academic Search

RESUMEN El suelo es un sistema abierto que tiende hacia un equilibrio dinámico acumulando y reciclando materia y energía a través del tiempo. Mediante un balance energético es posible evaluar la energía acumulada o la que circula a través de su masa. Esta miscelánea tiene por objetivo presentar aspectos teóricos y metodológicos para cuantificar la energía dinamizada durante la formación

AMÉRICO DEGIOANNI; ESTELA BRICCHI; EUGENIO HAMPP

2008-01-01

165

Fondo de Compensación Regional: Igualdad de oportunidades para la periferia colombiana  

Microsoft Academic Search

En el presente documento se propone la creación de un Fondo de Compensación Regional (FCR) para impulsar el desarrollo de la periferia de Colombia, la cual concentra más del 44% de la población total y el 60% de los habitantes con Necesidades Básicas Insatisfechas (NBI). Es importante resaltar que el principio que debe orientar la política del FCR es el

Luis Armando Galvis Aponte; Adolfo meisel R

2010-01-01

166

Programa em Educação a Distância para a Melhoria das Condições de Aprendizagem da Matemática  

Microsoft Academic Search

Resumo - A fim de fundamentar uma ação pedagógica diferenciada, frente ao elevado número de reprovações e desistências que ocorrem em disciplinas iniciais de Matemática na Universidade de Caxias do Sul, apresentamos um programa através do qual investigamos as reais possibilidades de constituir nova opção para alunos reprovados em Cálculo Diferencial e Integral I. Num ambiente virtual de aprendizagem os

Isolda G. De Lima; Laurete Z. Sauer

167

Convection in the Outer Planet Atmospheres Including ortho-para Hydrogen Conversion  

Microsoft Academic Search

Convective adjustment and diffusive schemes based on terrestrial methods are extended to outer planet applications in order to develop an algorithm that can be used in dynamical modeling of outer planetary flows. Over the temperature range between 50 K and 250 K the delayed conversion of ortho- hydrogen to para-hydrogen can have large effects on stratification. One-dimensional modeling of atmospheric

Michael D. Smith; Peter J. Gierasch

1995-01-01

168

Para-Professionals in Further Education: Changing Roles in Vocational Delivery  

ERIC Educational Resources Information Center

Roles and structures within further education colleges seem to be in constant change and development; roles are becoming blurred, and lecturers are taking on more management tasks. Alongside this has been the development of para-professional roles, using non-lecturers to undertake teaching tasks. This can allow for the greater involvement of…

Scott, Gill

2005-01-01

169

ESTUDIO MESOMECÁNICO DE LA FRACTURA DEL HORMIGÓN PARA DIFERENTES VELOCIDADES DE CARGA  

Microsoft Academic Search

Resumen. En este artículo se analiza el comportamiento del hormigón a un nivel mesomecánico de observación bajo cargas de tracción uniaxial dependientes del tiempo. Como punto de partida se ha empleado un modelo mesoestructural en 2D para materiales heterogéneos basado en elementos junta de espesor nulo, desarrollado dentro del grupo de investigación de la ETSECCPB-UPC. En este modelo, la estructura

Ricardo Lorefice; Guillermo Etse; Carlos M. López; Ignacio Carol

170

Desafíos en la gestión de tecnologías de información y comunicación para Colombia: caso de internet  

Microsoft Academic Search

Resumen Actualmente Colombia alcanza el 5,4% en el nivel de penetración de internet, mientras que en economías desarrolladas se observan niveles superiores al 40%. Con el objetivo de establecer los retos que el país debe superar para reducir la amplia brecha que estas cifras evidencian, se revisó el fenómeno de internet en diferentes ámbitos, identificándose nueve factores clave que influyen

Juan Camilo Uribe Véleza; Claudia Nelcy Jiménez Hernándezb; María Elena García Vergarac

2011-01-01

171

Indicadores de gestión urbana. Los observatorios urbano-territoriales para el desarrollo sostenible. Manizales, Colombia  

Microsoft Academic Search

Los Observatorios para el Desarrollo Sostenible del Municipio de Manizales en Colombia, hacen parte del Sistema de Monitoreo diseñado por el Municipio como apoyo a la gestión urbana local. A partir de los resultados de indicadores económicos, sociales y ambientales, los ciudadanos podrán evaluar de forma permanente el desempeño de programas y proyectos del Plan de Desarrollo Municipal y participar

Luz Stella Velásquez

2001-01-01

172

UPLC-ESI-MS/MS analysis of Sudan dyes and Para Red in food.  

PubMed

An analytical method for the simultaneous determination of Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B and Sudan IV) and Para Red in food by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) was developed. Samples were extracted with acetonitrile, and water added into the extract. The supernatant was analysed by UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on an Acquity BEH C(18) column, and detected by MS/MS with the multiple reaction monitoring mode. Matrix calibration was used for quantitative testing of the method. The linear matrix calibrations of Sudan dyes and Para Red were 2-50 and 10-250 ng g(-1), respectively, and the regression coefficients were >0.9945. The recoveries were 83.4-112.3% with good coefficients of variation of 2.0-10.8%. The limits of detection were between 0.3 and 1.4 ng g(-1) for the six Sudan dyes, and between 3.7 and 6.0 ng g(-1) for Para Red. The limits of quantification were between 0.9 and 4.8 ng g(-1) for the six Sudan dyes, and between 12.2 and 19.8 ng g(-1) for Para Red. PMID:20582780

Li, C; Wu, Y L; Shen, J Z

2010-09-01

173

Salud Para Su Corazón: A Community-Based Latino Cardiovascular Disease Prevention and Outreach Model  

Microsoft Academic Search

Cardiovascular disease (CVD) is the leading cause of death for Latinos living in the United States. This population is generally unaware of important lifestyle or behavioral changes that can prevent CVD. The National Heart, Lung, and Blood Institute (NHLBI) designed and implemented Salud para su Corazón (Health for Your Heart), a culturally appropriate, community-based, theory-driven intervention model. NHLBI's goals were:

Rina Alcalay; Matilde Alvarado; Hector Balcazar; Eileen Newman; Elmer Huerta

1999-01-01

174

SISTEMA PARA GESTIONAR LA ACTIVIDAD CIENTÍFICA DEL DEPARTAMENTO DE INFORMÁTICA DE LA UNIVERSIDAD DE GUANTÁNAMO  

Microsoft Academic Search

El sistema para gestionar la actividad científica del Departamento de Informática de la Universidad de Guantánamo surge debido a la necesidad de gestionar de manera más rápida, segura y eficaz los procesos que se desarrollan actualmente en dicho centro. Fue desarrollado utilizando los lenguajes PHP del lado del servidor con CodeIgniter como framework y JavaScript del lado del cliente. Se

Denis Boizan Romero

2012-01-01

175

Montagem e Resultados Preliminares de Aparato Experimental para Estudo Térmico de Materiais Ablativos  

Microsoft Academic Search

O estudo do fenômeno físico de ablação, que ocorre em determinados materiais usados em sistemas de proteção térmica de satélites, bem como a caracterização das propriedades térmicas dos mesmos são considerados de grande importância, por representar um ponto estratégico para a tecnologia espacial. No Brasil, os estudos de materiais ablativos têm sido realizados dentro da perspectiva do Programa Nacional de

Gabriel Antônio de Souza Júnior; Lucas Mello de Campos Arruda; Walber Ferreira Braga; Márcia Barbosa; Henriques Mantelli

176

Bacterial Inoculum Density and Probability of para-Nitrophenol Biodegradability Test Response  

Microsoft Academic Search

This study has been carried out to establish a model linking probability of positive response in para-nitrophenol biodegradability test to controlled variables of the test (suspended solids, SS; total bacteria, AODC; cultivable bacteria, CFU; specific biodegraders, MPN). Series of dilution of 11 raw inocula (6 activated sludges, 5 river waters) were tested. They reveal very dispersed values of biomass measured

G. Thouand; P. Friant; F. Bois; A. Cartier; A. Maul; J. C. Block

1995-01-01

177

Lenguajes de libre distribución para la gestión de redes basada en políticas  

Microsoft Academic Search

La gestión basada en políticas es uno de los últimos desarrollos en el área de gestión de redes y sistemas distribuidos. Este artículo presenta una propuesta del uso de lenguajes de libre distribución para la definición, edición y almacenamiento de políticas aplicables a la gestión de redes. 1 Introducción Las redes del mundo de las telecomunicaciones de hoy en día

Angélica Reyes; Antoni Barba; Ingeniería Telemática

178

Moléculas que marcam o tempo: implicações para os fenótipos circadianos Timekeeping molecules: implications for circadian phenotypes  

Microsoft Academic Search

Resumo Objetivo: Revisar resumidamente a literatura dos últimos 36 anos de pesquisa em cronobiologia molecular a fim de informar aos profissionais de saúde os avanços obtidos nesta área e os potenciais para aplicação na clínica médica. Método: Buscas na literatura foram realizadas utilizando as bases de dados PubMed e Scopus usando como palavras-chave \\

Danyella Silva Pereira; Sergio Tufik; Mario Pedrazzoli

179

Gestión de recursos de un navegador Web para prevenir ataques contra la privacidad en Tor  

Microsoft Academic Search

Resumen—En este trabajo presentamos una propuesta para el despliegue de políticas de autorización contextuales sobre navegadores Web. El objetivo de nuestra propuesta es la automatización del proceso de control de recursos de un navegador Web cuando el contexto de navegación varía. Cuando esto sucede, los requisitos de seguridad del navegador cambian igualmente. La utilización de nuestra propuesta está orientada a

G. Navarro-Arribas; J. Garcia-Alfaro; O. Mula-Valls; J. Herrera-Joancomartí

180

Intact cluster and chordate-like expression of ParaHox genes in a sea star  

PubMed Central

Background The ParaHox genes are thought to be major players in patterning the gut of several bilaterian taxa. Though this is a fundamental role that these transcription factors play, their activities are not limited to the endoderm and extend to both ectodermal and mesodermal tissues. Three genes compose the ParaHox group: Gsx, Xlox and Cdx. In some taxa (mostly chordates but to some degree also in protostomes) the three genes are arranged into a genomic cluster, in a similar fashion to what has been shown for the better-known Hox genes. Sea urchins possess the full complement of ParaHox genes but they are all dispersed throughout the genome, an arrangement that, perhaps, represented the primitive condition for all echinoderms. In order to understand the evolutionary history of this group of genes we cloned and characterized all ParaHox genes, studied their expression patterns and identified their genomic loci in a member of an earlier branching group of echinoderms, the asteroid Patiria miniata. Results We identified the three ParaHox orthologs in the genome of P. miniata. While one of them, PmGsx is provided as maternal message, with no zygotic activation afterwards, the other two, PmLox and PmCdx are expressed during embryogenesis, within restricted domains of both endoderm and ectoderm. Screening of a Patiria bacterial artificial chromosome (BAC) library led to the identification of a clone containing the three genes. The transcriptional directions of PmGsx and PmLox are opposed to that of the PmCdx gene within the cluster. Conclusions The identification of P. miniata ParaHox genes has revealed the fact that these genes are clustered in the genome, in contrast to what has been reported for echinoids. Since the presence of an intact cluster, or at least a partial cluster, has been reported in chordates and polychaetes respectively, it becomes clear that within echinoderms, sea urchins have modified the original bilaterian arrangement. Moreover, the sea star ParaHox domains of expression show chordate-like features not found in the sea urchin, confirming that the dynamics of gene expression for the respective genes and their putative regulatory interactions have clearly changed over evolutionary time within the echinoid lineage.

2013-01-01

181

In para totale...una cosa da panico...sulla lingua dei giovani in Italia (In para totale...una cosa da panico...The Language of Young People in Italy).  

ERIC Educational Resources Information Center

Describes and analyzes the language of young people in Italy today. Particular focus is on the expressions using "para" (e.g., "in para totale" = to be very bored or worried) and the phrase "una cosa da panico" (something terrible or its opposite something wonderful). (CFM)

Marcato, Carla

1997-01-01

182

La política brasileña para los residuos sólidos urbanos. Los planteamientos de catadores y empresarios en sus páginas electrónicas  

Microsoft Academic Search

El gobierno brasileño señala la posibilidad de aprobar la política nacional para los residuos sólidos urbanos (PNRS). La propuesta del Proyecto de Ley 1991\\/07 está en trámite en la cámara de los diputados desde el año 1991. Los senadores mantuvieron una charla con los catadores, empresarios del reciclaje y empresarios de servicios de gestión de residuos sólidos urbanos para conocer

Fábio Fonseca Figueiredo

2008-01-01

183

Gastric perforation: a late complication of abdominal radiation for para-aortic lymph node metastasis from cervical squamous carcinoma.  

PubMed

Gastric perforation was found at laparotomy for acute abdominal pain in a woman treated with pelvic and abdominal radiation for squamous cell carcinoma of the uterine cervix metastatic to the para-aortic nodes. This case may provide additional evidence suggesting that risks involved in para-aortic radiation may outweigh the benefits. PMID:6655724

Dini, M M; Miller, M

1983-12-01

184

Gastric Perforation: A Late Complication of Abdominal Radiation for Para-Aortic Lymph Node Metastasis From Cervical Squamous Carcinoma  

PubMed Central

Gastric perforation was found at laparotomy for acute abdominal pain in a woman treated with pelvic and abdominal radiation for squamous cell carcinoma of the uterine cervix metastatic to the para-aortic nodes. This case may provide additional evidence suggesting that risks involved in para-aortic radiation may outweigh the benefits.

Dini, Morteza M.; Miller, Madeline

1983-01-01

185

EVALUATION OF PARA-DICHLOROBENZENE EMISSIONS FROM SOLID MOTH REPELLANT AS A SOURCE OF INDOOR AIR POLLUTION  

EPA Science Inventory

Mothcakes made of para-dichlorobenzene have been widely available for the general population to be used as a moth repellant to protect garments from insect damage. Usually, a mothcake is expected to last for weeks or even months during which the para-dichlorobenzene emits slowly ...

186

Herramienta de simulación interactiva y de bajo coste para el desarrollo de laboratorios virtuales de comunicaciones ópticas  

Microsoft Academic Search

En el ámbito académico, los laboratorios virtuales constituyen una solución pedagógica muy adecuada para aquellos casos donde resulta difícil poder disponer de recursos de laboratorio costosos. En este artículo se exponen resultados preliminares de la implementación de una plataforma de simulación interactiva para la enseñanza de materias relacionadas con las comunicaciones ópticas. Tras el primer año de aplicación de esta

Francisco Ramos Pascual

187

LA PARTICIPACIÓN Y SU IMPORTANCIA PARA EL DESARROLLO CULTURAL EN LA COMUNIDAD DE GASTÓN EN EL MUNICIPIO DE MAJIBACOA  

Microsoft Academic Search

La participación es un elemento indispensable que hace posible poner a prueba y desarrollar las capacidades humanas y estructuras, para desde la comunidad producir cultura para esta. Así se convierte en el elemento que posibilita un verdadero desarrollo endógeno en tanto proceso de cambio y transformación. Al proporcionar cauces de participación sociocultural, se estimula el desarrollo de determinadas relaciones y

Ana Margarita Gómez Aguilera; Rafaela Macías Reyes

2012-01-01

188

Comienza la construcción de instalación patrocinada por el NCI en Puerto Rico para realizar estudios clínicos sobre el cáncer  

Cancer.gov

El gobierno de Puerto Rico ha destinado $196 millones de dólares para construir un hospital oncológico de 287 000 pies cuadrados en San Juan, que contará con 96 camas. El nuevo hospital es el primero en su clase en la región caribeña y en él se llevarán a cabo tratamientos para el cáncer y estudios clínicos.

189

EVALUATION OF PARA-DICHLOROBENZENE EMISSIONS FROM SOLID MOTH REPELLANT AS A SOURCE OF INDOOR AIR POLLUTION  

EPA Science Inventory

The paper reports results of dynamic and static chamber tests to evaluate para-dichlorobenzene emission rates from mothcakes. he data were analyzed by a model that assumes that the para-dichlorobenzene emission from mothcakes is a temperature-sensitive sublimation process. ull-sc...

190

SISTEMA DE INDICADORES PARA LA EVALUACIÓN DE LA APLICACIÓN DEL SISTEMA DE GESTIÓN AMBIENTAL EN EMPRESAS CONSTRUCTORAS  

Microsoft Academic Search

Se tuvo como objetivo la propuesta de un sistema de indicadores para la evaluación de la aplicación del Sistema de Gestión Ambiental en empresas constructoras y la elaboración de un software para el procesamiento de los mismos, que contribuya a elevar la eficacia de la evaluación del desempeño ambiental y los resultados de las organizaciones de este tipo. Este sistema

Ninfa del Carmen Moncada Serrano

2012-01-01

191

Molecular characterization of neurally expressing genes in the para sodium channel gene cluster of Drosophila  

SciTech Connect

To elucidate the mechanisms regulating expression of para, which encodes the major class of sodium channels in the Drosophila nervous system, we have tried to locate upstream cis-acting regulatory elements by mapping the transcriptional start site and analyzing the region immediately upstream of para in region 14D of the polytene chromosomes. From these studies, we have discovered that the region contains a cluster of neurally expressing genes. Here we report the molecular characterization of the genomic organization of the 14D region and the genes within this region, which are: calnexin (Cnx), actin related protein 14D (Arp14D), calcineurin A 14D (CnnA14D), and chromosome associated protein (Cap). The tight clustering of these genes, their neuronal expression patterns, and their potential functions related to expression, modulation, or regulation of sodium channels raise the possibility that these genes represent a functionally related group sharing some coordinate regulatory mechanism. 76 refs., 11 figs.

Hong, Chang-Sook; Ganetzky, B. [Univ. of Wisconsin, Madison, WI (United States)

1996-03-01

192

H2CS abundances and ortho-to-para ratios in interstellar clouds  

NASA Technical Reports Server (NTRS)

Several H2CS ortho and para transitions have been observed toward interstellar molecular clouds, including cold, dark clouds and star-forming regions. H2CS fractional abundances f(H2CS) about 1-2 10 to the -9th relative to molecular hydrogen toward TMC-1, Orion A, and NGC 7538, and about 5 10 to the -10th for L134N are derived. The H2CS ortho-to-para ratios in TMC-1 are about 1.8 toward the cyanopolyyne peak and the ammonia peak, which may indicate the thermalization of H2CS on 10 K grains. A ratio of about 3, the statistical value, for Orion (3N, 1E) and NGC 7538 is derived, while a value of about 2 for Orion (KL) is found.

Minh, Y. C.; Irvine, W. M.; Brewer, M. K.

1991-01-01

193

Para-aortic lymph node metastasis in malignant dysgerminoma of the ovary.  

PubMed

Dysgerminomas comprise approximately 2-5% of all ovarian malignancies and mostly affect young adolescent women. Primary comprehensive surgery and adjuvant chemotherapy consisting of bleomycin, etoposide, and cisplatin (BEP) are the current recommended treatment options, the latter reserved for advanced stages (FIGO II-IV). We report two patients aged 20 and 26 years who presented with an initial FIGO stage IA, but inadequately assessed. Both were subsequently diagnosed with recurrent malignant dysgerminoma and para-aortic lymph node metastasis. Neither had received comprehensive staging at initial surgery nor adjuvant radio or chemotherapy. Both needed extensive surgery and multiagent chemotherapy for survival and belong to the small percentage of FIGO IA dysgerminoma patients showing a relapse. Comprehensive initial surgery including systematic para-aortic lymphadenectomy and adjuvant chemotherapy at tertiary referral centers is needed to minimize the treatment burden. PMID:19900144

Kasenda, Benjamin; Harter, Philipp; Hirsch, Tobias; Ast, Alexander; Buhrmann, Christine; Glaser, Florian; Du Bois, Andreas

2009-01-01

194

Solid and liquid heat capacities of n-alkyl para-aminobenzoates near the melting point.  

PubMed

The expression that relates the ideal mole fraction solubility of a crystalline compound to physicochemical properties of the compound includes a term involving the difference in the heat capacities of the solid and liquid forms of the solute, delta Cp. There are two alternate conventions which are employed to eliminate this term. The first assumes that the term involving delta Cp, or delta Cp itself, is zero. The alternate assumption assigns the value of the entropy of fusion to the differential heat capacity. The relative validity of these two assumptions was evaluated using the straight-chain alkyl para-aminobenzoates as test compounds. The heat capacities of the solid and liquid forms of each of the para-aminobenzoates, near the respective melting point, were determined by differential scanning calorimetry. The data lead one to conclude that the assumption that the differential heat capacity is not usually negligible and is better approximated by the entropy of fusion. PMID:2293215

Neau, S H; Flynn, G L

1990-11-01

195

Action spectra for ultraviolet photosensitized killing of mammalian cells by misonidazole and para-nitroacetophenone  

SciTech Connect

Chinese hamster fibroblasts in monolayer culture were exposed to ulraviolet radiation at 313, 334, 365, 380, and 405 nm in the presence of either misonidazole or para-nitroacetophenone, drugs which act as both photosensitizers and radiosensitizers of cell killing. Survival was measured by a colony-forming assay. The resulting action spectra for cell death photosensitized by the drugs (the reciprocals of the exposures required at each wavelength to reduce cell survival to a given level) closely match their absorption spectra over a range of three orders of magnitude. These results demonstrate that cells can be killed upon excitation of misonidazole or para-nitroacetophenone in the absence of any other types of energy deposition or biomolecular damage.

Fisher, G.J. (Centre Hospitalier Universitaire, Quebec, Canada); Sutherland, B.M.; Sutherland, J.C.

1983-05-01

196

Incentivos para atraer y retener personal de salud de zonas rurales del Per?: un estudio cualitativo  

PubMed Central

El objetivo fue identificar incentivos de atracción y retención en zonas rurales y distantes de Ayacucho, Perú. Fueron realizadas entrevistas en profundidad con 80 médicos, enfermeras, obstetras y técnicos (20 por grupo) de las zonas más pobres y con 11 funcionarios. No existen políticas sistemáticas de atracción y retención de personal de salud en Ayacucho. Los principales incentivos, en orden de importancia, fueron mejoras salariales, oportunidades de formación y capacitación, estabilidad laboral y nombramiento, mejoras en infraestructura y equipos, e incremento del personal. Se mencionaron también mejoras en la vivienda y alimentación, mayor cercanía con la familia y reconocimiento por el sistema de salud. Existen coincidencias y singularidades entre los distintos grupos sobre los incentivos clave para estimular el trabajo rural, que deben considerarse al diseñar políticas públicas. Las iniciativas del Estado deben comprender procesos rigurosos de monitoreo y evaluación, para asegurar que las mismas tengan el impacto deseado.

Huicho, Luis; Canseco, Francisco Diez; Lema, Claudia; Miranda, J. Jaime; Lescano, Andres G.

2014-01-01

197

Development of an integrated remote monitoring technique and its application to para-stressing bridge system  

NASA Astrophysics Data System (ADS)

Bridge monitoring system via information technology is capable of providing more accurate knowledge of bridge performance characteristics than traditional strategies. This paper describes not only an integrated Internet monitoring system that consists of a stand-alone monitoring system (SMS) and a Web-based Internet monitoring system (IMS) for bridge maintenance but also its application to para-stressing bridge system as an intelligent structure. IMS, as a Web-based system, is capable of addressing the remote monitoring by introducing measuring information derived from SMS into the system through Internet or intranet connected by either PHS or LAN. Moreover, the key functions of IMS such as data management system, condition assessment, and decision making with the proposed system are also introduced in this paper. Another goal of this study is to establish the framework of a para-stressing bridge system which is an intelligent bridge by integrating the bridge monitoring information into the system to control the bridge performance automatically.

Miyamoto, Ayaho; Motoshita, Minoru; Casas, Joan R.

2013-12-01

198

Avaliação de fontes de amônia para o tratamento de fenos de gramíneas tropicais. 2. Compostos nitrogenados  

Microsoft Academic Search

RESUMO - Este estudo foi desenvolvido para se avaliarem as alterações nos conteúdos de compostos nitrogenados dos fenos de braquiária decumbens ( Brachiaria decumbnes Stapf) e jaraguá (Hyparrhenia rufa Ness Stapf) não-tratados, tratados com uréia (U - 5,4% da MS), uréia (UL - 5,4% da MS) mais labe-labe (Lablab purpureus L. Sweet, cv. Highworth-3,0% da MS) ou amônia anidra (NH3

Ricardo Andrade Reis; Luis Roberto de Andrade Rodrigues; Kléber Tomás de Resende; João Ricardo Alves Pereira; Ana Cláudia Ruggieri

2001-01-01

199

Lanzamiento del estudio de tratamiento personalizado para el cáncer de seno  

Cancer.gov

Hoy se inició el Estudio de Asignación de Opciones Individualizadas de Tratamiento (Trial Assigning IndividuaLized Options for Treatment (Rx), o TAILORx, el cual evaluará si los genes que están frecuentemente asociados con el riesgo de recurrencia entre las mujeres con cáncer de seno en etapa inicial pueden ser utilizados para asignar a las pacientes el tratamiento más adecuado y efectivo. Preguntas y respuestas

200

Desarrollo y Propiedades Psicométricas de la Escala de Autoeficacia para la Depresión en Adolescentes (EADA)  

Microsoft Academic Search

Self-efficacy questionnaires used with adolescents are mostly youth-adapted adult measures or scales developed to assess general perceived self-efficacy. The purpose of this study was to develop and assess the psychometric properties of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA). Additionally, the Emotional Self-efficacy subscale from the Self-Efficacy Questionnaire for Children and the Children's Depression Inventory-Short Version were

MIRELLA DÍAZ-SANTOS; EDUARDO CUMBA-AVILÉS; GUILLERMO BERNAL; CARMEN RIVERA-MEDINA

2008-01-01

201

Electrochemical intercalation of sodium ions into poly( para-phenylene) in carbonate-based electrolytes  

Microsoft Academic Search

Electrochemical intercalation of sodium ions into poly(para-phenylene) (PPP) has been carried out in NaClO4—carbonate electrolytes (EC, PC and their mixture in the volumic ratio of 1\\/1). The same electrochemical behavior has been observed in the three electrolytes. The galvanostatic curves exhibit potential slope changes which are characteristic of multiphase system; this behavior is confirmed by cyclic voltammetry. Our experimental conditions

M. Dubois; J. Ghanbaja; D. Billaud

1997-01-01

202

Projeto do sistema anti-ressonante da fiação dos transdutores para o detector Mario Schenberg  

NASA Astrophysics Data System (ADS)

O detector de ondas gravitacionais Mario Schenberg está sendo projetado e construído pelo grupo Gráviton. Sua construção está ocorrendo no Laboratório de Estado Sólido e Baixas Temperaturas (LESBT) da Universidade de São Paulo, na cidade de São Paulo. Esse detector possui uma massa ressonante esférica de cobre-alumínio, com 65 cm de diâmetro, pesando aproximadamente 1150 Kg, suspensa por um sistema de isolamento vibracional, que se encontra em fase de testes preliminares. A real eficácia desse sistema, entretanto, só poderá ser comprovada quando o detector estiver aparelhado com, pelo menos, um transdutor eletromecânico de altíssima sensibilidade acoplado à massa ressonante. Neste momento, não só este sistema de isolamento vibracional será posto em teste, como o do projeto da fiação que transporta os sinais de microondas até os transdutores e destes para a pré-amplificação. Apesar dessa fiação ter sido projetada para não apresentar nenhum contato com a superfície esférica da antena, de maneira a não haver nenhuma transmissão de ruído vibracional do laboratório para esta, deve-se minimizar o ruído microfônico produzido nessa fiação por oscilações mecânicas, uma vez que ela não utiliza nenhum sistema de isolamento vibracional. Com o intuito de resolver este problema, projetamos uma estrutura, formada por pequenos cilindros conectados por barras, a qual não terá nenhuma ressonância mecânica na faixa de freqüências de interesse para detecção (3000 - 3400 Hz). Desta forma, as vibrações nessa faixa não serão amplificadas. O projeto foi feito usando iterativamente, de maneira a otimizar os resultados obtidos, o programa de elementos finitos Msc/Nastran. Através de simulações feitas neste programa, determinamos os parâmetros geométricos ideais a serem utilizados, os quais proporcionam a maior região espectral de interesse livre de ressonâncias.

Vieira, S. J.., Jr.; Melo, J. L.

2003-08-01

203

Diffusion Monte Carlo study of the equation of state of solid para- H2  

Microsoft Academic Search

The diffusion Monte Carlo method is used to exactly solve the N -body Schroedinger equation for a system of para- H2 molecules at different densities described as pointlike particles interacting via an effective potential. We compare the results obtained using two of the most used model interactions, i.e., the Silvera-Goldman and the Buck potentials in order to assess their validity.

Francesco Operetto; Francesco Pederiva

2006-01-01

204

Acute renal failure following para-phenylenediamine (PPD) poisoning: a case report and review.  

PubMed

We report a case of systemic poisoning with para-phenylenediamine (PPD) presenting with characteristic features of severe angioneurotic edema, rhabdomyolysis and intravascular hemolysis with hemoglobinuria culminating in acute renal failure. Though rare in western countries, such poisoning is not uncommon in East Africa, Indian subcontinent and Middle East countries. We discuss here the clinical features and key management issues of systemic PPD poisoning. PMID:15354985

Anuradha, S; Arora, Sandeep; Mehrotra, S; Arora, A; Kar, P

2004-05-01

205

Contraluminal para-aminohippurate (PAH) transport in the proximal tubule of the rat kidney  

Microsoft Academic Search

In order to study the specificity for contraluminal para-aminohippurate (PAH) transport, the inhibitory potency of aliphatic dicarboxylates on3H-PAH influx, as well as the inhibitory effect on35SO42-- and3H-succinate influx, from the interstitium into cortical tubular cells in situ has been determined. The following was found:1.Testing a homologous series of dicarboxylates-ranging from the 2 C oxalate to the 10 C sebacate —

K. J. Ullrich; G. Rumrich; G. Fritzsch; S. Klöss

1987-01-01

206

Diastereoselective phenol para-alkylation: access to a cross-conjugated cyclohexadienone en route to resiniferatoxin.  

PubMed

We document a route for the synthesis of a densely functionalized spiro-fused 2,5-cyclohexadienone as an intermediate for the synthesis of resineferatoxin. The strategy is based on an unprecedented diastereoselective, intramolecular phenol para-alkylation to a cross-conjugated cyclohexadienone. In the course of these synthetic studies we developed rapid access to a chiral nitrile possessing a quaternary stereocenter and disclose an unusual acetal rearrangement from a dioxane, which favors the corresponding dioxepane. PMID:15524486

Ritter, Tobias; Zarotti, Pablo; Carreira, Erick M

2004-11-11

207

Anomalous NMR Line Shapes in Solid Ordered OrthoHydrogen and Para-Deuterium  

Microsoft Academic Search

Some highly anomalous features have been observed in the low-temperature NMR spectrum of high-purity (> 99% J=1), solid para-deuterium. The intensity of the low-frequency side of the Pake doublet is enhanced and that of the high-frequency side reduced, sometimes becoming negative, corresponding to an emission of power. The anomaly is particularly pronounced and of the opposite sign for the I=2

Walter N. Hardy; A. John Berlinsky

1973-01-01

208

Microsystems for determining the heterogeniety of head and neck cancer cell populations by para-magnetophoresis  

Microsoft Academic Search

This paper is focused on the design, fabrication and characterization of a continuous flow magnetophoretic microseparator for the separation of selectively tagged cells using para-magnetophoresis. The microseparator was characterized experimentally using head and neck cells lines 212LN and 686LN-M4E as a case study. The microfluidic separation system can separate the selectively tagged cancer cells depending on their membrane protein expression

Y. Jung; D. Wang; G. Chen; D. Shin; K. H. Han; A. B. Frazier

2009-01-01

209

Significado de los cambios en los senos: Guía para la salud de la mujer  

Cancer.gov

Información sobre cambios o padecimientos específicos de los senos y cómo se detectan, diagnostican y tratan estos cambios. Aquí se explica que si bien la mayoría de los cambios en los senos no son cancerosos, estos deben ser examinados por un médico. También se ofrece información sobre los pasos a seguir después de un resultado anormal de una mamografía y se incluye una lista de preguntas para el doctor.

210

Significado de los cambios en los senos: Guía para la salud de la mujer  

Cancer.gov

E-book que describe los cambios o padecimientos específicos de los senos e incluye información sobre cómo se detectan, diagnostican y tratan estos cambios. Aquí se explica que si bien la mayoría de los cambios en los senos no son cancerosos, estos deben ser examinados por un médico. También se ofrece información sobre los pasos a seguir después de un resultado anormal de una mamografía y se incluye una lista de preguntas para el doctor.

211

Para-sexiphenyl-CdSe\\/ZnS nanocrystal hybrid light emitting diodes  

Microsoft Academic Search

CdSe\\/ZnS core\\/shell nanocrystals (NCs) are integrated into para-sexiphenyl (p-6P) based hybrid light emitting diodes, to obtain green and red emission in addition to blue emission originated from p-6P. For the active region of the devices, ultrathin layers of p-6P and NCs are deposited by hot wall epitaxy and spin casting, respectively, resulting in current-voltage characteristics with small leakage currents and

C. Simbrunner; G. Hernandez-Sosa; E. Baumgartner; G. Hesser; J. Roither; W. Heiss; H. Sitter

2009-01-01

212

Revision of Vertical Banded Gastroplasty Complicated by a Large Para-esophageal Hernia  

Microsoft Academic Search

Patients who have undergone bariatric surgery and present with upper abdominal symptoms pose a diagnostic and management challenge.\\u000a This is a case report of a 53-year-old lady who presented a number of years after vertical banded gastroplasty with upper\\u000a abdominal pain and weight gain. Radiological investigation demonstrated a large para-esophageal hernia including the stapled\\u000a area of the stomach, but with

Mansoor Khan; Fred Lee; Roger Ackroyd

2010-01-01

213

Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature  

Microsoft Academic Search

Terahertz time-domain spectroscopy has been used to measure the absorption of water vapor in 0.2-2.4 THz range from low to high humidity at room temperature. The observed absorption lines are due to the water molecular rotations in the ground vibrational state. We find that the absorption strength of para transitions increases as humidity increases, while the absorption strength of ortho

X. Xin; H. Altan; A. Saint; D. Matten; R. R. Alfano

2006-01-01

214

New High Temperature Lithium Para-Toluene Sulfonate (LIPTSA) Salt for Rechargeable Batteries  

Microsoft Academic Search

Lithium para-toluene sulfonate [LIPTSA] was used for lithium rechargeable batteries, with poly(methyl methacrylate) [PMMA] as the base material. Tri block copolymer of PEO-PPO-PEO was used to increase the solubility of lithium salts in PMMA matrix. FTIR, TGA, XRD, Impedance spectroscopy & SEM were used for characterizations and morphological studies. LIPTSA salt is stable up to 375°C. The highest room temperature

Sreejith K R; Akhil Kumar Sen

2012-01-01

215

A rapid HPLC method for determination of Sudan dyes and Para Red in red chilli pepper  

Microsoft Academic Search

A rapid high-performance liquid chromatography (HPLC) system consisting of an ultraviolet-visible (UV–VIS) detector was developed for the separation and determination of Sudan dyes (I, II, III, and IV) and Para Red in red chilli peppers. The chromatographic separation was achieved on a reverse phase C18 column with isocratic elution, using a mobile phase of acetonitrile\\/methanol (80:20, v\\/v); detector was set

Erdal Erta?; Hayrettin Özer; Cesarettin Alasalvar

2007-01-01

216

Determination of Sudan Dyes and Para Red in Duck Muscle and Egg by UPLC  

Microsoft Academic Search

A simple, sensitive and reliable UPLC method was developed and validated for the simultaneous determination of six Sudan dyes\\u000a (Sudan Red G, Sudan I, II, III, Sudan Red 7B, Sudan IV) and Para Red in duck muscle and egg samples. Samples were extracted with acetonitrile, then the extract was dried under\\u000a rotary evaporation and dissolved in acetonitrile\\/0.1% formic acid (85:15,

Cun Li; Ting Yang; Yan Zhang; Yin-Liang Wu

2009-01-01

217

UPLC-ESI-MS\\/MS analysis of Sudan dyes and Para Red in food  

Microsoft Academic Search

An analytical method for the simultaneous determination of Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B and Sudan IV) and Para Red in food by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS\\/MS) was developed. Samples were extracted with acetonitrile, and water added into the extract. The supernatant was analysed by UPLC-MS\\/MS after refrigeration and

C. Li; Y. L. Wu; J. Z. Shen

2010-01-01

218

Um Processador Construtivista na Web para documentos anotados (PcWDa)  

Microsoft Academic Search

Resumo A notacao XML, cada vez mais, desempenha um papel im- portante na representacao textual da informacao estruturada ou semi- estruturada, sendo a norma mais vulgarizada para marcacao de do- cumentos. Torna-se por isso indispensavel a existencia de ferramentas que possibilitem desenvolver(editar e validar) eficientemente documen- tos XML. Neste artigo pretende-se discutir a especificacao e o desenvolvimento de uma dessas

Mariana Isabel Ferreira; Sandra Cristina Lopes; Pedro Rangel Henriques

219

Surgical resection of a solitary para-aortic lymph node metastasis from hepatocellular carcinoma.  

PubMed

Lymph node (LN) metastases from hepatocellular carcinoma (HCC) are considered uncommon. We describe the surgical resection of a solitary para-aortic LN metastasis from HCC. A 65-year-old Japanese man with B-type liver cirrhosis was admitted for the evaluation of a liver tumor. He had already undergone radiofrequency ablation, transcatheter arterial chemoembolization, and percutaneous ethanol injection therapy for HCC. Despite treatment, viable regions remained in segments 4 and 8. We performed a right paramedian sectionectomy with partial resection of the left paramedian section of the liver. Six months later, serum concentrations of alpha-fetoprotein (189 ng/mL) and PIVKA-2 (507 mAU/mL) increased. Enhanced computed tomography of the abdomen revealed a tumor (20 mm in diameter) on the right side of the abdominal aorta. Fluorine-18 fluorodeoxyglucose positron emission tomography revealed an increased standard uptake value. There was no evidence of recurrence in other regions. Esophagogastroduodenoscopy and colonoscopy revealed no malignant tumor in the gastrointestinal tract. Para-aortic LN metastasis from HCC was thus diagnosed. We performed lymphadenectomy. Histopathological examination revealed that the tumor was largely necrotic, with poorly differentiated HCC on its surface, which confirmed the suspected diagnosis. After 6 mo tumor marker levels were normal, with no evidence of recurrence. Our experience suggests that a solitary para-aortic LN metastasis from HCC can be treated surgically. PMID:22736929

Ueda, Junji; Yoshida, Hiroshi; Mamada, Yasuhiro; Taniai, Nobuhiko; Mineta, Sho; Yoshioka, Masato; Kawano, Youichi; Shimizu, Tetsuya; Hara, Etsuko; Kawamoto, Chiaki; Kaneko, Keiko; Uchida, Eiji

2012-06-21

220

Comparação de modelos para o cálculo de perturbações orbitais devidas à maré terrestre  

NASA Astrophysics Data System (ADS)

Aplicações recentes de satélites artificiais com finalidades geodinâmicas requerem órbitas determinadas com bastante precisão. Em particular marés terrestres influenciam o potencial terrestre causando perturbações adicionais no movimento de satélites artificiais, as quais tem sido medidas por diversos processos. A atração exercida pela lua e pelo sol sobre a terra produz deslocamentos elásticos em seu interior e uma protuberância em sua superfície. O resultado é uma pequena variação na distribuição da massa na terra, consequentemente no geopotencial. As perturbações nos elementos orbitais de satélites artificiais terrestres devidas a maré terrestre podem ser estudadas a partir das equações de Lagrange, considerando-se um conveniente potencial. Por outro lado, como tem sido feito pelo IERS, as mudanças induzidas pela maré terrestre no geopotencial podem ser convenientemente modeladas como variações nos coeficientes Cnm e Snm do geopotencial. As duas teorias ainda não foram comparados para um mesmo satélite. Neste trabalho são apresentadas e comparadas as variações de longo período e seculares nas perturbações orbitais devidas à maré terrestre, calculadas por um modelo simples, o de Kozai, e pelo modelo do IERS. Resultados preliminares mostram, para os satélites SCD2 e CBERS1, e para a Lua em movimento elíptico e precessionando, as perturbações seculares no argumento do perigeu e na longitude do nodo ascendente.

Vieira Pinto, J.; Vilhena de Moraes, R.

2003-08-01

221

Otimização de procedimento de manobra para indução de reentrada de um satélite retornável  

NASA Astrophysics Data System (ADS)

Veículos espaciais que retornam à Terra passam por regimes de velocidade e condições de vôo distintos. Estas diferenças dificultam sua concepção aerodinâmica e o planejamento de seu retorno. A partir de uma proposta de um veículo orbital retornável (satélite SARA, em desenvolvimento no IAE/CTA) para realização de experimentos científicos e tecnológicos em ambiente de baixa gravidade, surge a necessidade de realizarem-se estudos considerando-se os aspectos relativos à sua aerodinâmica. Após o lançamento, o veículo deve permanecer em órbita pelo tempo necessário para a condução de experimentos, sendo depois direcionado à Terra e recuperado em solo. A concepção aerodinâmica é de importância para o vôo em suas diversas fases e deve considerar aspectos relativos à estabilização Aerodinâmica e ao arrasto atmosférico, sendo este último de importância crucial na análise do aquecimento a ser enfrentado. A manobra de retorno inclui considerações sobre as condições atmosféricas e dinâmica de reentrada, devendo ser calculada de forma mais precisa possível. O trabalho proposto avalia estudos da dinâmica de vôo de um satélite recuperável considerando aspectos relativos à determinação orbital com GPS, técnica utilizada com sucesso na CONAE, e seu comportamento aerodinâmico em vôo balístico de retorno, com ênfase em sua fase de reentrada atmosférica. Busca-se otimizar a manobra de reentrada de tal forma que a utilização do sistema GPS garanta minimizar a área de impacto com o solo.

Schulz, W.; Suarez, M.

2003-08-01

222

The ortho:para-H_2 ratio in C- and J-type shocks  

NASA Astrophysics Data System (ADS)

We have computed extensive grids of models of both C- and J-type planar shock waves, propagating in dark, cold molecular clouds, in order to study systematically the behaviour of the ortho:para-H_2 ratio. Careful attention was paid to both macroscopic (dynamical) and microscopic (chemical reactions and collisional population transfer in H_2) aspects. We relate the predictions of the models to observational determinations of the ortho:para-H_2 ratio using both pure rotational lines and rovibrational lines. As an illustration, we consider ISO and ground-based H_2 observations of HH 54. Neither planar C-type nor planar J-type shocks appear able to account fully for these observations. Given the additional constraints provided by the observed ortho:para H_2 ratios, a C-type bowshock, or a C-type precursor followed by a J-type shock, remain as plausible models. Tables~2a-f and 4a-f are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

Wilgenbus, D.; Cabrit, S.; Pineau des Forêts, G.; Flower, D. R.

2000-04-01

223

An incidentally discovered asymptomatic para-aortic paraganglioma with Peutz-Jeghers syndrome.  

PubMed

Peutz-Jeghers syndrome (PJS) is an autosomal dominant inherited disorder characterized by mucocutaneous melanin pigmentation and gastrointestinal (GI) tract hamartomatous polyps and an increased risk of malignancy. In addition to polyposis, previous studies have reported increased risk of GI and extraGI malignancies in PJS patients, compared with that of the general population. The most common extraintestinal malignancies reported in previous studies are pancreatic, breast, ovarian and testicular cancers.We report the case of a 17-year-old boy who presented with generalized weakness, recurrent sharp abdominal pain and melena, had exploratory laparotomy and ileal resection for ileo-ileal intussusception. Pigmentation of the buccal mucosa was noted. An abdominal computed tomography scan (CT) revealed multiple polyps in small bowel loops. Gastroscopy revealed multiple dimunitive polyps in stomach and pedunculated polyp in duodenum. Colonoscopy revealed multiple colonic polyps. Pathological examination of the polyps confirmed hamartomas with smooth muscle arborization, compatible with Peutz-Jeghers polyps. CT scan guided left para-aortic lymph node biopsy revealed the characteristic features of extra-adrenal para-aortic paraganglioma. Although cases of various GI and extra GI malignancies in PJS patients has been reported, the present case appears to be the first in literature in which the PJS syndrome was associated with asymptomatic extraadrenal para-aortic paraganglioma. Patients with PJS should be treated by endoscopic or surgical resection and need whole-body screening. PMID:23150026

Butt, Nazish; Salih, Mohammad; Khan, Mohammad Rizwan; Ahmed, Rashida; Haider, Zishan; Shah, Syed Hasnain Ali

2012-01-01

224

Transoral, retromolar, para-tonsillar approach to the styloid process in 6 patients with Eagle's syndrome  

PubMed Central

Objectives: Eagle’s syndrome is caused by an elongated or mineralised styloid process and characterised by facial and pharyngeal pain, odynophagia and dysphagia. Diagnosis is based on clinical findings. However radiologic imaging, like panoramic radiograph, helps to confirm the diagnosis. There are different treatments of the Eagle’s syndrome. Anti-inflammatory medication (carbamazepime, corticosteroids) and/or surgical interventions are established. The aim of the different surgical techniques is to resect the elongated styloid process near the skull base. Study Design: A transoral, retromolar, para-tonsillar approach was performed to expose and resect the elongated calcified styloid process in a consecutive series of six patients. The use of different angled ring curettes, generally used in hypophysis surgery, facilitated the preparation of the styloid process through the surrounding tissue to the skull base, without a compromise to the surrounding tissue. Clinical examinations were performed pre- and postoperatively (3 month and after 1 year after surgery) in all patients. Results: No intra- or postoperative complications were observed. The hypophysis ring curettes facilitated the preparation of the styloid process to the skull base. Conclusions: The transoral, retromolar, para-tonsillar approach is a secure and fast method to resect an elongated symptomatic styloid process. Side effects of the classical transoral trans-tonsillar approach did not occur. Key words:Retromolar, para-tonsillar approach, Eagle syndrome, clinical features.

Eckert, Alexander W.; Scheller, Christian

2014-01-01

225

[Formation of para-Bombay phenotype caused by homozygous or heterozygous mutation of FUT1 gene].  

PubMed

This study was aimed to explore the molecular mechanisms for para-Bombay phenotype formation. The H antigen of these individuals were identified by serological techniques. The full coding region of alpha (1, 2) fucosyltransferase (FUT1) gene of these individuals was amplified by high-fidelity polymerase chain reaction (PCR). PCR product was identified by TOPO cloning sequencing. Analysis and comparison were used to explore the mechanisms of para-bombay phenotype formation in individuals. The results indicated that the full coding region of FUT1 DNA was successfully amplified by PCR and gel electrophoresis. DNA sequencing and analysis found that h1 (547-552delAG) existed in one chromosome and h4 (35C > T) existed in the other chromosome of NO.1 individual. Meantime, h1 (547-552delAG) was found in two chromosomes of NO.2 and NO.3 individual. It also means that FUT1 gene of NO.1 individual was h1h4 heterozygote, FUT1 gene of NO.2 and NO.3 individuals were h1h1 homozygote. It is concluded that homozygous and heterozygous mutation of FUT1 gene can lead to the formation of para-Bombay phenotype. PMID:24598677

Zhang, Jin-Ping; Zheng, Yan; Sun, Dong-Ni

2014-02-01

226

Fragrance material review on 1-(para-menthen-6-yl)-1-propanone.  

PubMed

A toxicologic and dermatologic review of 1-(para-Menthen-6-yl)-1-propanone when used as a fragrance ingredient is presented. 1-(para-Menthen-6-yl)-1-propanone is a member of the fragrance structural group Alkyl Cyclic Ketones. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 1-(para-Menthen-6-yl)-1-propanone were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization, data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (2013) [Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M., Fryer, A.D., Greim, H., Miyachi, Y., Saurat, J.H., Sipes, I.G., 2013 A Toxicologic and Dermatologic Assessment of Alkyl Cyclic Ketones When Used as Fragrance Ingredients. Submitted with this manuscript.] for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances. PMID:24246181

Scognamiglio, J; Letizia, C S; Api, A M

2013-12-01

227

Modeling, design, chiral aspects and role of para-substituents in aryloxypropranolamine based beta-blockers.  

PubMed

The conformation of the beta-blockers viz. metoprolol, atenolol, bisoprolol, betaxolol and celiprolol has been investigated using Perturbative Configuration Interaction of Localized Orbitals (PCILO) method. The conformational energy maps have been constructed for both the enantiomers (R and S) by rotating the molecule from the para-substituent end. The aryloxypropranolamine moiety adopts the same conformation for all antagonists. The graphical view of R- and S- form of these antagonists in the lowest energy conformation reveals that it is only in the S- form of beta-blockers, all the three functionalities--aromatic moiety, amino and beta-hydroxyl groups are available for interaction with beta-adrenoceptors. The para-substituents of the beta-blockers adopt a conformation which is perpendicular to the aryloxy moiety resulting in an L-shaped structure. The beta-antagonists possibly partition into the lipid bilayer through the para-substituents and the aryloxypropranolamine moiety containing the functionalities, thus, lies parallel to the plane of lipid bilayer for interaction with beta-adrenoceptors. Superimposition of S-bisoprolol in lowest energy conformation with the 3rd putative transmembranous segment of the beta-adrenoceptors reveals that the aromatic moiety, amino and beta-hydroxyl groups of antagonists are involved in interaction with the side chains of Trp-109, Asp-113 and Thr-110 respectively. This has been further substantiated by the interaction studies on the model systems. PMID:10549157

Nandel, F S; Dhaliwal, R K; Singh, B

1999-02-01

228

Theoretical study of the design of a catalyst for para to ortho hydrogen conversion  

NASA Technical Reports Server (NTRS)

The theory of Petzinger and Scalapino (1973) was thoroughly reviewed, and all of the basic equations for paramagnetic para to ortho hydrogen catalysis re-derived. There are only a few minor phase errors and errors of omission in the description of the theory. Three models (described by Petzinger and Scalapino) for the rate of para to ortho H2 catalysis were worked out, and uniform agreement obtained to within a constant factor of 2 pi. The analytical methods developed in the course of this study were then extended to two new models, which more adequately describe the process of surface catalysis including transfer of hydrogen molecules onto and off of the surface. All five equations for the para to ortho catalytic rate of conversion are described. The two new equations describe the catalytic rate for these models: H2 on the surface is a 2-D gas with lifetime tau; and H2 on the surface is a 2-D liquid undergoing Brownian motion (diffusion) with surface lifetime tau.

Coffman, Robert E.

1992-01-01

229

Atlas de aves: Un metodo para documentar distribucion y seguir poblaciones  

USGS Publications Warehouse

Los Atlas de Aves son proyectos nacionales o regionalies para trazar en mapas la distribucion en reproduccion de cada especie de ave. Ese procedimiento se esta usando en Europa, Australia, Nueva Zelanda, Norteamerica, y partes de Africa. El tama?o de los cuadrados varia de medio grado de latitud y Iongitud hasta 5 x 5 km. El trabajo de campo de cada proyecto exige aproxlmadamente cinco a?os, pero los aficionados pueden llevar a cabo la mayor parte del trabajo. Es posible almacenar los resultados en un computador personal. Hay muchos beneficios: (I) se presenta la distribucion corriente de las aves de la nacion, del estado, o de la Iocalidad; (2) se desarrolla nueva informacion especialmente sobre especies raras o en peligro; (3) se descubren areas que tienen una avlfauna sobresaliente o habitats raros y ayuda a su proteccion, (4) se documentan cambios de dlstribucion; (5) se pueden usar para documentar cambios de poblacion, especialmente en los tropicos donde otros metodos son mas dificiles de usar porque hay muchas especies y no hay muchos observadores calificados en la identificacion de sonidos de las aves; (6) son proyectos buenos de investigacion para estudiantes graduados; (7) los turistas y los jefes de excursiones de historia natural pueden contribuir con muchas informaciones

Robbins, C.S.; Dowell, B.A.; Dawson, D.K.

1988-01-01

230

Dynamic interplay of ParA with the polarity protein, Scy, coordinates the growth with chromosome segregation in Streptomyces coelicolor.  

PubMed

Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, ParA, positions the newly replicated origin-proximal region of the chromosome by interacting with ParB complexes assembled on parS sites located close to the origin. During the formation of unigenomic spores from multi-genomic aerial hyphae compartments of Streptomyces coelicolor, ParA is developmentally triggered to form filaments along the hyphae; this promotes the accurate and synchronized segregation of tens of chromosomes into prespore compartments. Here, we show that in addition to being a segregation protein, ParA also interacts with the polarity protein, Scy, which is a component of the tip-organizing centre that controls tip growth. Scy recruits ParA to the hyphal tips and regulates ParA polymerization. These results are supported by the phenotype of a strain with a mutant form of ParA that uncouples ParA polymerization from Scy. We suggest that the ParA-Scy interaction coordinates the transition from hyphal elongation to sporulation. PMID:23536551

Ditkowski, Bartosz; Holmes, Neil; Rydzak, Joanna; Donczew, Magdalena; Bezulska, Martyna; Ginda, Katarzyna; Kedzierski, Pawel; Zakrzewska-Czerwi?ska, Jolanta; Kelemen, Gabriella H; Jakimowicz, Dagmara

2013-03-01

231

Functional expression of Drosophila para sodium channels. Modulation by the membrane protein TipE and toxin pharmacology.  

PubMed

The Drosophila para sodium channel alpha subunit was expressed in Xenopus oocytes alone and in combination with tipE, a putative Drosophila sodium channel accessory subunit. Coexpression of tipE with para results in elevated levels of sodium currents and accelerated current decay. Para/TipE sodium channels have biophysical and pharmacological properties similar to those of native channels. However, the pharmacology of these channels differs from that of vertebrate sodium channels: (a) toxin II from Anemonia sulcata, which slows inactivation, binds to Para and some mammalian sodium channels with similar affinity (Kd congruent with 10 nM), but this toxin causes a 100-fold greater decrease in the rate of inactivation of Para/TipE than of mammalian channels; (b) Para sodium channels are >10-fold more sensitive to block by tetrodotoxin; and (c) modification by the pyrethroid insecticide permethrin is >100-fold more potent for Para than for rat brain type IIA sodium channels. Our results suggest that the selective toxicity of pyrethroid insecticides is due at least in part to the greater affinity of pyrethroids for insect sodium channels than for mammalian sodium channels. PMID:9236205

Warmke, J W; Reenan, R A; Wang, P; Qian, S; Arena, J P; Wang, J; Wunderler, D; Liu, K; Kaczorowski, G J; Van der Ploeg, L H; Ganetzky, B; Cohen, C J

1997-08-01

232

ParA encoded on chromosome II of Deinococcus radiodurans binds to nucleoid and inhibits cell division in Escherichia coli.  

PubMed

Bacterial genome segregation and cell division has been studied mostly in bacteria harbouring single circular chromosome and low-copy plasmids. Deinococcus radiodurans, a radiation-resistant bacterium, harbours multipartite genome system. Chromosome I encodes majority of the functions required for normal growth while other replicons encode mostly the proteins involved in secondary functions. Here, we report the characterization of putative P-loop ATPase (ParA2) encoded on chromosome II of D. radiodurans. Recombinant ParA2 was found to be a DNA-binding ATPase. E. coli cells expressing ParA2 showed cell division inhibition and mislocalization of FtsZ-YFP and those expressing ParA2-CFP showed multiple CFP foci formation on the nucleoid. Although, in trans expression of ParA2 failed to complement SlmA loss per se, it could induce unequal cell division in slmAminCDE double mutant. These results suggested that ParA2 is a nucleoid-binding protein, which could inhibits cell division in E. coli by affecting the correct localization of FtsZ and thereby cytokinesis. Helping slmAminCDE mutant to produce minicells, a phenotype associated with mutations in the 'Min' proteins, further indicated the possibility of ParA2 regulating cell division by bringing nucleoid compaction at the vicinity of septum growth. PMID:23938382

Charaka, Vijaya Kumar; Mehta, Kruti P; Misra, H S

2013-09-01

233

Dynamic interplay of ParA with the polarity protein, Scy, coordinates the growth with chromosome segregation in Streptomyces coelicolor  

PubMed Central

Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, ParA, positions the newly replicated origin-proximal region of the chromosome by interacting with ParB complexes assembled on parS sites located close to the origin. During the formation of unigenomic spores from multi-genomic aerial hyphae compartments of Streptomyces coelicolor, ParA is developmentally triggered to form filaments along the hyphae; this promotes the accurate and synchronized segregation of tens of chromosomes into prespore compartments. Here, we show that in addition to being a segregation protein, ParA also interacts with the polarity protein, Scy, which is a component of the tip-organizing centre that controls tip growth. Scy recruits ParA to the hyphal tips and regulates ParA polymerization. These results are supported by the phenotype of a strain with a mutant form of ParA that uncouples ParA polymerization from Scy. We suggest that the ParA–Scy interaction coordinates the transition from hyphal elongation to sporulation.

Ditkowski, Bartosz; Holmes, Neil; Rydzak, Joanna; Donczew, Magdalena; Bezulska, Martyna; Ginda, Katarzyna; Kedzierski, Pawel; Zakrzewska-Czerwinska, Jolanta; Kelemen, Gabriella H.; Jakimowicz, Dagmara

2013-01-01

234

Identification of an intact ParaHox cluster with temporal colinearity but altered spatial colinearity in the hemichordate Ptychodera flava  

PubMed Central

Background ParaHox and Hox genes are thought to have evolved from a common ancestral ProtoHox cluster or from tandem duplication prior to the divergence of cnidarians and bilaterians. Similar to Hox clusters, chordate ParaHox genes including Gsx, Xlox, and Cdx, are clustered and their expression exhibits temporal and spatial colinearity. In non-chordate animals, however, studies on the genomic organization of ParaHox genes are limited to only a few animal taxa. Hemichordates, such as the Enteropneust acorn worms, have been used to gain insights into the origins of chordate characters. In this study, we investigated the genomic organization and expression of ParaHox genes in the indirect developing hemichordate acorn worm Ptychodera flava. Results We found that P. flava contains an intact ParaHox cluster with a similar arrangement to that of chordates. The temporal expression order of the P. flava ParaHox genes is the same as that of the chordate ParaHox genes. During embryogenesis, the spatial expression pattern of PfCdx in the posterior endoderm represents a conserved feature similar to the expression of its orthologs in other animals. On the other hand, PfXlox and PfGsx show a novel expression pattern in the blastopore. Nevertheless, during metamorphosis, PfXlox and PfCdx are expressed in the endoderm in a spatially staggered pattern similar to the situation in chordates. Conclusions Our study shows that P. flava ParaHox genes, despite forming an intact cluster, exhibit temporal colinearity but lose spatial colinearity during embryogenesis. During metamorphosis, partial spatial colinearity is retained in the transforming larva. These results strongly suggest that intact ParaHox gene clustering was retained in the deuterostome ancestor and is correlated with temporal colinearity.

2013-01-01

235

Estudio de terapias dirigidas para el cáncer de seno estableció un modelo de estudios clínicos a nivel mundial  

Cancer.gov

Dos medicamentos de acción dirigida, diseñados para tratar una forma agresiva de cáncer de seno (mama), se pusieron a prueba en un estudio que incluyó a 8 000 participantes en 44 países. Si bien la finalidad del estudio fue ayudar a que los investigadores determinaran si el tratamiento combinado con trastuzumab y lapatinib para el tratamiento del cáncer de seno HER2 positivo en estado inicial era mejor que la terapia solo con trastuzumab, los resultados del estudio no indicaron que existan ventajas para las mujeres al recibir la combinación de fármacos de trastuzumab o lapatinib.

236

Identification and Characterization of Catabolic para-Nitrophenol 4-Monooxygenase and para-Benzoquinone Reductase from Pseudomonas sp. Strain WBC-3?  

PubMed Central

Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen, and energy. In order to identify the genes involved in this utilization, we cloned and sequenced a 12.7-kb fragment containing a conserved region of NAD(P)H:quinone oxidoreductase genes. Of the products of the 13 open reading frames deduced from this fragment, PnpA shares 24% identity to the large component of a 3-hydroxyphenylacetate hydroxylase from Pseudomonas putida U and PnpB is 58% identical to an NAD(P)H:quinone oxidoreductase from Escherichia coli. Both PnpA and PnpB were purified to homogeneity as His-tagged proteins, and they were considered to be a monomer and a dimer, respectively, as determined by gel filtration. PnpA is a flavin adenine dinucleotide-dependent single-component PNP 4-monooxygenase that converts PNP to para-benzoquinone in the presence of NADPH. PnpB is a flavin mononucleotide-and NADPH-dependent p-benzoquinone reductase that catalyzes the reduction of p-benzoquinone to hydroquinone. PnpB could enhance PnpA activity, and genetic analyses indicated that both pnpA and pnpB play essential roles in PNP mineralization in strain WBC-3. Furthermore, the pnpCDEF gene cluster next to pnpAB shares significant similarities with and has the same organization as a gene cluster responsible for hydroquinone degradation (hapCDEF) in Pseudomonas fluorescens ACB (M. J. Moonen, N. M. Kamerbeek, A. H. Westphal, S. A. Boeren, D. B. Janssen, M. W. Fraaije, and W. J. van Berkel, J. Bacteriol. 190:5190-5198, 2008), suggesting that the genes involved in PNP degradation are physically linked.

Zhang, Jun-Jie; Liu, Hong; Xiao, Yi; Zhang, Xian-En; Zhou, Ning-Yi

2009-01-01

237

Identification and characterization of catabolic para-nitrophenol 4-monooxygenase and para-benzoquinone reductase from Pseudomonas sp. strain WBC-3.  

PubMed

Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen, and energy. In order to identify the genes involved in this utilization, we cloned and sequenced a 12.7-kb fragment containing a conserved region of NAD(P)H:quinone oxidoreductase genes. Of the products of the 13 open reading frames deduced from this fragment, PnpA shares 24% identity to the large component of a 3-hydroxyphenylacetate hydroxylase from Pseudomonas putida U and PnpB is 58% identical to an NAD(P)H:quinone oxidoreductase from Escherichia coli. Both PnpA and PnpB were purified to homogeneity as His-tagged proteins, and they were considered to be a monomer and a dimer, respectively, as determined by gel filtration. PnpA is a flavin adenine dinucleotide-dependent single-component PNP 4-monooxygenase that converts PNP to para-benzoquinone in the presence of NADPH. PnpB is a flavin mononucleotide-and NADPH-dependent p-benzoquinone reductase that catalyzes the reduction of p-benzoquinone to hydroquinone. PnpB could enhance PnpA activity, and genetic analyses indicated that both pnpA and pnpB play essential roles in PNP mineralization in strain WBC-3. Furthermore, the pnpCDEF gene cluster next to pnpAB shares significant similarities with and has the same organization as a gene cluster responsible for hydroquinone degradation (hapCDEF) in Pseudomonas fluorescens ACB (M. J. Moonen, N. M. Kamerbeek, A. H. Westphal, S. A. Boeren, D. B. Janssen, M. W. Fraaije, and W. J. van Berkel, J. Bacteriol. 190:5190-5198, 2008), suggesting that the genes involved in PNP degradation are physically linked. PMID:19218392

Zhang, Jun-Jie; Liu, Hong; Xiao, Yi; Zhang, Xian-En; Zhou, Ning-Yi

2009-04-01

238

Comportamento da dose glandular versus contraste do objeto em mamografia: determinação de formalismo semi-empírico para diferentes combinações alvo-filtro  

Microsoft Academic Search

OBJETIVO: Verificar o efeito da mudança no contraste do objeto, tempo de exposição e dose de radiação quando diferentes espessuras de filtração de molibdênio (Mo) e ródio (Rh) são empregadas em mamógrafos. MATERIAIS E MÉTODOS: Realizaram-se medidas da exposição na entrada da pele com uma câmara de ionização para diferentes espessuras para os filtros de Mo e Rh. Para determinar

Gabriela Hoff; Carlos Eduardo de Almeida; Gary T. Barnes

2006-01-01

239

Multi-determination of Para red and Sudan dyes in egg by a broad specific antibody based enzyme linked immunosorbent assay  

Microsoft Academic Search

Para red and Sudan dyes (Sudan 1, 2, 3, 4, and Sudan G) have been proven to show the potential carcinogenic effect to human. This study first reported an indirect competitive immunoassay (ELISA) for simultaneous detection of the six red dyes in egg. Two immunogens of Para red were prepared by coupling the deoxidized Para red to carrier protein by

Xiang Cai Chang; Xiu Zhi Hu; Yan Qin Li; Yan Jiao Shang; Yan Zheng Liu; Gao Feng; Jian Ping Wang

2011-01-01

240

Diseño, análisis y manufactura de un sistema de fijación interna para tratamiento de fracturas en el primer metacarpiano  

Microsoft Academic Search

En la Universidad Central de Venezuela se está desarrollando un sistema intramedular bloqueado para\\u000atratamiento de fracturas diafisiarias en los huesos metacarpianos como una nueva alternativa para este tipo\\u000ade lesiones. El dispositivo es poco invasivo y permite movilidad temprana de la mano al paciente postoperado\\u000aacortando el tiempo de recuperación. En este trabajo se presentan los diferentes procesos que

Gabriela Contreras; Miguel Cerrolaza; Manuel Martínez; Nils Götzen

1970-01-01

241

A computa»c~ao numerica como ferramenta para o professor de F¶‡sica do Ensino Medio  

Microsoft Academic Search

A proposta deste trabalhoe apresentar ao professor de F¶‡sica do ensino medio uma forma de empregar recur- sos computacionais para esclarecer e aprofundar conceitos de F¶‡sica que s~ao explorados de forma limitada por n~ao se poder recorrer ao Calculo Diferencial e Integral. O p^endulo simplese usado como prototipo para o trata- mento sugerido. Mostramos que apenas com o aux¶‡lio de

Augusto Cesar; Claudio Gon; Marcus Vinicius; Tovar Costa

242

A Introdução de Astronomia Básica para Estudantes de 5 e 6 Séries do Ensino Fundamental  

NASA Astrophysics Data System (ADS)

Com intuito de despertar o interesse pelo estudo da astronomia, desenvolveu-se entre 2003 e 2006 no Centro Educacional do Serviço Social da Indústria situado no município de Mauá, São Paulo, um trabalho com duração de 12 meses para turmas de 11 e 12 anos, sendo três turmas por período (2003 / 2004, 2004 / 2005 e 2005 / 2006). O trabalho realizado, objetivando a introdução da astronomia básica com observações de constelações e das fases da Lua, permitindo estender-se a outros corpos celestes, iniciou-se com visita ao planetário Mundo Estelar, localizado no Ipiranga, São Paulo levantou-se a questão da importância do estudo da astronomia e foi lançado aos estudantes um trabalho de observação, com a proposta de localizar as constelações e compreender as fases da Lua, para o registro de tais observações, foram distribuídos mapas celestes, pastas, planilhas de anotações com lacunas para, constelações, fases da Lua e relatos, onde os estudantes acrescentaram pesquisas e relatórios. Os resultados dos 346 estudantes foram que 86,7% (300) concluíram a etapa de observação, destes 300 estudantes 43,3% (130) pesquisaram sobre as constelações e 19,0% (57) localizaram até quatro constelações. Dos 346 estudantes, 44,2% (153) registraram as fases da Lua equivocadamente e 10,4% (36) anexaram reportagens sobre astronomia. Conclui-se que os estudantes se dividiram em pesquisadores, sendo os estudantes que registraram e anexaram informações e, os observadores que preencheram as planilhas de observações, além de desenvolverem habilidades e competências relacionadas ao estudo da astronomia.

Gonzaga, E. P.; Voelzke, M. R.

2008-09-01

243

Molecular basis for H blood group deficiency in Bombay (Oh) and para-Bombay individuals.  

PubMed

The penultimate step in the biosynthesis of the human ABO blood group oligosaccharide antigens is catalyzed by alpha-(1,2)-fucosyltransferase(s) (GDP-L-fucose: beta-D-galactoside 2-alpha-L-fucosyltransferase, EC 2.4.1.69), whose expression is determined by the H and Secretor (SE) blood group loci (also known as FUT1 and FUT2, respectively). These enzymes construct Fuc alpha 1-->2Gal beta-linkages, known as H determinants, which are essential precursors to the A and B antigens. Erythrocytes from individuals with the rare Bombay and para-Bombay blood group phenotypes are deficient in H determinants, and thus A and B determinants, as a consequence of apparent homozygosity for null alleles at the H locus. We report a molecular analysis of a human alpha-(1,2)-fucosyltransferase gene, thought to correspond to the H blood group locus, in a Bombay pedigree and a para-Bombay pedigree. We find inactivating point mutations in the coding regions of both alleles of this gene in each H-deficient individual. These results define the molecular basis for H blood group antigen deficiency in Bombay and para-Bombay phenotypes, provide compelling evidence that this gene represents the human H blood group locus, and strongly support a hypothesis that the H and SE loci represent distinct alpha-(1,2)-fucosyltransferase genes. Candidate sequences for the human SE locus are identified by low-stringency Southern blot hybridization analyses, using a probe derived from the H alpha-(1,2)-fucosyltransferase gene. PMID:7912436

Kelly, R J; Ernst, L K; Larsen, R D; Bryant, J G; Robinson, J S; Lowe, J B

1994-06-21

244

Supported transition metal catalysts for para- to ortho-hydrogen conversion  

NASA Technical Reports Server (NTRS)

The main goal of this study was to develop and improve on existing catalysts for the conversion of ortho- to para-hydrogen. Starting with a commercially available Air Products nickel silicate, which had a beta value of 20, we were trying to synthesize catalysts that would be an improvement to AP. This was accomplished by preparing silicates with various metals as well as different preparation methods. We also prepared supported ruthenium catalysts by various techniques using several metal precursors to improve present technology. What was also found was that the activation conditions prior to catalytic testing was highly important for both the silicates and the supported ruthenium catalysts. While not the initial focus of the research, we made some interesting observations into the adsorption of H2 on ruthenium. This helped us to get a better understanding of how ortho- to para-H2 conversion takes place, and what features in a catalyst are important to optimize activity. Reactor design was the final area in which some interesting conclusions were drawn. As discussed earlier, the reactor catalyst bed must be constructed using straight 1/8 feet OD stainless steel tubing. It was determined that the use of 1/4 feet OD tubing caused two problems. First, the radius from the center of the bed to the wall was too great for thermal equilibrium. Since the reaction of ortho- to para-H2 is exothermic, the catalyst bed center was warmer than the edges. Second, the catalyst bed was too shallow using a 1/4 feet tube. This caused reactant blow-by which was thought to decrease the measured activity when the flow rate was increased. The 1/8 feet tube corrected both of these concerns.

Brooks, Christopher J.; Wang, Wei; Eyman, Darrell P.

1994-01-01

245

Structural and vibrational investigation of para-nitraminopyridine N-oxide  

Microsoft Academic Search

The X-ray and vibrational spectroscopic analysis of para-nitraminopyridine N-oxide are reported. The crystals of investigated compound belong to P21 of the monoclinic system, Z=4, a=3.735Å, b=11.767Å, c=14.679Å and ?=93.27°. Room temperature powder infrared and Raman spectra of the title compound and its deuterated analogue were measured.The molecular structure of p-nitraminopyridine N-oxide has been calculated with the aid of density functional

J. Oszust; J. Baran; A. Pietraszko; M. Drozd; Z. Talik

2005-01-01

246

Para-hexaphenyl nanofiber growth on Au-coated porous alumina templates  

NASA Astrophysics Data System (ADS)

The availability of easy and reproducible methods for formation of periodically nanostructured surfaces allows one to study the quasi-epitaxial growth of nanowires on such artificially modified substrates. Here, we demonstrate that crystalline nanofibers of para-hexaphenyl can grow on porous alumina templates with high pore regularity once the templates have been coated by a thin Au film. Nanofibers of that kind represent a model system for the general class of organic nanowires which have chemically changeable optoelectronic properties and hence are of interest for integration into future optoelectronic devices.

Madsen, M.; Kartopu, G.; Andersen, N. L.; Es-Souni, M.; Rubahn, H.-G.

2009-08-01

247

Path integral molecular dynamics simulation of solid para-hydrogen with an aluminum impurity  

NASA Astrophysics Data System (ADS)

The equilibrium properties of an aluminum impurity trapped in solid para-hydrogen have been studied. The results were compared to those of a previous study by Krumrine et al. [J. Chem. Phys. 113 (2000) 9079] with an atomic boron. In the presence of vacancy defect, when the orientation-dependent Al- pH 2 potential is used, the Al atom is displaced to a position half way between its original substituted site and the vacancy site. Thermodynamic results also indicate that the presence of a neighboring vacancy helps to stabilize the Al impurity to a far greater extent than in the case of the B impurity.

Mirijanian, Dina T.; Alexander, Millard H.; Voth, Gregory A.

2002-11-01

248

Photophysical and acid-base properties of para-substituted N,N-dimethylanilines  

NASA Astrophysics Data System (ADS)

Ultraviolet absorption and fluorescence spectra were collected for para-substituted N,N-dimethylanilines in aqueous solution at various pH conditions. Two fluorescing forms were observed for all studied compounds, one protonated (ANsH+) and the second unprotonated (ANs) each of them with specific spectroscopic properties. Changing pH of solution results in the displacement of the equilibrium between two forms. It was found that protonated aniline derivatives in aqueous solutions undergo very fast excited-state proton dissociation and the pKa values obtained from absorption and fluorescence spectra are similar. The excited state pKa? values were calculated using the Förster cycle method.

Szabelski, Mariusz; Bojarski, Piotr; Wieczorek, Zbigniew

2013-05-01

249

Photochemical transformation of nitrate in the presence of para-halogenated phenols in frozen solutions  

NASA Astrophysics Data System (ADS)

Photochemical reactions leading to the chemical transformation of trace compounds in the atmosphere do not only occur in the atmospheric gas and liquid phases, but also in the tropospheric ice phase. The photochemical reactions of trace compounds embedded in ice have important implications for the composition of the atmospheric boundary layer in ice and snow covered regions and for interpretation of concentration profiles in snow and ice in the context of the composition of the past atmosphere. One of the prominent reactions is the photolysis of nitrate. This reaction is well established in natural waters, and is of interest since formation of highly mutagenic/carcinogenic nitro-compounds is possible. In contrast, the photochemical behaviour of nitrate in ice and snow is more complex. The photolysis of nitrate embedded in ice has been shown to generate OH radical, NO2(g) and NO(g) as primary photoproducts, but little is known how this photochemistry is affected by the presence of organic impurities embedded in the ice surface. In this work, we studied the effect of the presence of para-halogenated phenols on the photo-transformation of frozen nitrate solutions by Diffuse Reflective Infrared Fourier Transform Spectroscopy (DRIFTS). Moreover, the evolution of volatile nitrogen oxides to the gas phase was monitored by a commercial chemiluminescence NO/NOy monitor, chemical ionization mass spectrometry (CIMS), and thermal-dissociation cavity ring-down spectroscopy (TD-CRDS). In addition, some of the organic intermediate products were characterized by GC/MS and HPLC/PDA. We show that DRIFTS can provide a qualitative picture of the chemical transformations that take place at the ice surface and kinetic data on the phototransformation of nitrate. The photochemistry of frozen solutions of nitrate in the presence of various para-halogenated phenols was found to be dependent on the ice temperature, pH, the light intensity, and the concentration and nature of para-halogenated phenols added. The release of NOy species to the gas-phase was dramatically accelerated by low pH values as well as the nature of para-halogen, in the order Cl>Br>F. The major species released were identified as NO2 and HONO.

Abida, O.; Osthoff, H. D.; Sutherland, T. C.

2010-12-01

250

Para[ 18 F]fluorobenzylguanidine kinetics in a canine coronary artery occlusion model  

Microsoft Academic Search

Background  The kinetics of para-[18F]fluorobenzylguanidine ([18F]PFBG) were investigated in a canine coronary artery occlusion model.\\u000a \\u000a \\u000a \\u000a Methods and Results  Five dogs were imaged by positron emission tomography (PET) before and after complete surgical ligation of the left anterior\\u000a descending coronary artery. PET studies included a 10-minute dynamic [13N]NH3 perfusion scan, followed 1 hour later by 3-hour dynamic [18F]PFBG scanning. [18F]PFBG and [13N]NH3 images

Clifford R. Berry; Pradeep K. Garg; Timothy R. DeGrado; Peter Hellyer; William Weber; Sudha Garg; Bernard Hansen; Michael R. Zalutsky; R. Edward Coleman

1996-01-01

251

Pressure-enhanced ortho-para conversion in solid hydrogen up to 58 GPa  

PubMed Central

We measured the ortho-para conversion rate in solid hydrogen by using Raman scattering in a diamond-anvil cell, extending previous measurements by a factor of 60 in pressure. We confirm previous experiments that suggested a decrease in the conversion rate above about 0.5 GPa. We observe a distinct minimum at 3 GPa followed by a drastic increase in the conversion rate to our maximum pressure of 58 GPa. This pressure enhancement of conversion is not predicted by previous theoretical treatments and must be due to a new conversion pathway.

Eggert, Jon H.; Karmon, Eran; Hemley, Russell J.; Mao, Ho-kwang; Goncharov, Alexander F.

1999-01-01

252

Analysis of Para Red and Sudan Dyes in Egg Yolk by UPLC–MS–MS  

Microsoft Academic Search

Matrix solid-phase dispersion (MSPD) with alumina N as adsorbent has been used for extraction of para red, Sudan 1, Sudan\\u000a 2, Sudan 3, and Sudan 4 dyes from egg yolk. The extracts were analyzed by ultra-performance liquid chromatography–tandem mass\\u000a spectrometry (UPLC–MS–MS). Mean recovery for the five dyes ranged from 63.2 to 98.6%, with CV 0.55–10.00%. One sample was\\u000a confirmed to

Xiaolin Hou; Yonggang Li; Shoujun Cao; Zhongwen Zhang; Yongnin Wu

2010-01-01

253

Metabolic influences for mutation induction curves after exposure to Sudan-1 and para red.  

PubMed

Sudan-1 and para red are industrial dyes that have been illegally added to some foodstuffs, leading to withdrawal of the adulterated products throughout the UK since 2003. This resulted in international concern that arose because Sudan-1 is classified by International Agency for Research on Cancer as a Category 3 carcinogen. However, little is known about the dose response of this chemical at low, more biologically relevant, doses. The study therefore aimed to characterize the dose response for gene mutation and chromosomal damage induced by two azo dyes, namely Sudan-1 and para red. Gene mutations were analysed using the hypoxanthine phosphoribosyltransferase forward mutation assay and chromosomal damage was measured using the cytokinesis-blocked micronucleus assay. Two cell lines were used in these investigations. These were the AHH-1 cell line, which inducibly expresses CYP1A1, and the MCL-5 cell line derived from a subpopulation of AHH-1 cells that expresses a particularly high level of CYP1A1 activity. The MCL-5 cell line has also been transfected with two plasmids that stably express CYP1A2, CYP2A6 and CYP3A4 and all four of these CYP enzymes are known to metabolically activate Sudan-1. AHH-1 cells were used to investigate the dose response of the azo dyes, and MCL-5 cells were used to see if the dose response changed with increased metabolism. Sudan-1 induced a non-linear dose-response curve for gene mutation and chromosomal damage in AHH-1 cells. The genotoxic activity of Sudan-1 was greatly increased in MCL-5 cells. This indicated that the oxidation metabolites from Sudan-1 were both more mutagenic and more clastogenic than the parent compound. Para red also demonstrated a non-linear dose response for both gene mutation and chromosome damage in AHH-1 cells, and an increase in micronuclei induction was observed after increased oxidative metabolism in MCL-5 cells. Sudan-1 and para red are genotoxic chemicals with non-linear dose responses in AHH-1 but not in MCL-5 cells, and oxidative metabolism increases the genotoxic effect of both compounds. PMID:20197315

Johnson, George E; Quick, Emma L; Parry, Elizabeth M; Parry, James M

2010-07-01

254

Salud Para Su Corazon (Health for Your Heart) Community Health Worker Model  

PubMed Central

This article describes 6 Salud Para Su Corazon (SPSC) family of programs that have addressed cardiovascular disease risk reduction in Hispanic communities facilitated by community health workers (CHWs) or Promotores de Salud (PS). A synopsis of the programs illustrates the designs and methodological approaches that combine community-based participatory research for 2 types of settings: community and clinical. Examples are provided as to how CHWs can serve as agents of change in these settings. A description is presented of a sustainability framework for the SPSC family of programs. Finally, implications are summarized for utilizing the SPSC CHW/PS model to inform ambulatory care management and policy.

Balcazar, H.; Alvarado, M.; Ortiz, G.

2012-01-01

255

Photoresponse of poly([ital para]-phenylenevinylene) light-emitting diodes  

SciTech Connect

We have studied the photoresponses of poly([ital para]-phenylene vinylene) (PPV) light-emitting diodes (LED's) with PPV derivatives sandwiched between tin oxide (ITO) and metals including calcium, aluminum, and copper. Under illumination all diodes exhibit relatively large photoconductive I(V) responses which cross the dark I(V) curve at a forward-bias voltage V[sub 0] that scales with the difference in work functions between the ITO and metal electrodes, the open-circuit voltage saturates at V[sub 0] and is temperature independent, and the enhanced electroluminescence intensity of the illuminated LED's correlates with the photocurrent. (AIP)

Wei, X.; Raikh, M.; Vardeny, Z.V. (Department of Physics, University of Utah, Salt Lake City, Utah 84112 (United States)); Yang, Y. (UNIAX Corporation, 5375 Overpass Road, Santa Barbara, California 93111 (United States)); Moses, D. (Institute of Polymers and Organic Solids, University of California, Santa Barbara, California 93106 (United States))

1994-06-15

256

Variability of kinetic parameters due to biomass acclimation: Case of para-nitrophenol biodegradation  

Microsoft Academic Search

The study regards para-nitrophenol (p-NP) removal by a mixed culture in a batch reactor under aerobic conditions performed at low ratio substrate (p-NP) to p-NP degrading microorganisms (0.09

Fériel Rezouga; Moktar Hamdi; Mathieu Sperandio

2009-01-01

257

A para-nitrophenol phosphonate probe labels distinct serine hydrolases of Arabidopsis.  

PubMed

Activity-based protein profiling represents a powerful methodology to probe the activity state of enzymes under various physiological conditions. Here we present the development of a para-nitrophenol phosphonate activity-based probe with structural similarities to the potent agrochemical paraoxon. We demonstrate that this probes labels distinct serine hydrolases with the carboxylesterase CXE12 as the predominant target in Arabidopsis thaliana. The designed probe features a distinct labeling pattern and therefore represents a promising chemical tool to investigate physiological roles of selected serine hydrolases such as CXE12 in plant biology. PMID:21763150

Nickel, Sabrina; Kaschani, Farnusch; Colby, Tom; van der Hoorn, Renier A L; Kaiser, Markus

2012-01-15

258

Near-resonance scattering of the para-H2 vibrons in (ortho-H2)x(para-H2)1-x mixed crystals  

NASA Astrophysics Data System (ADS)

The p-H2 vibrons hae been studied by high-resolution Raman scattering in mixed crystals of (o-H2)x(p-H2)1-x, (HD)x(p-H2)1-x, and (o-D2)0.069(p-H2)0.931. For increasing o-H2 concentration, the line shape broadens and becomes asymmetric with a tail towards higher frequencies. This effect is less pronounced in the HD- and the o-D2-doped crystals, where the energy difference between the p-H2 vibron and the stretching vibration of the impurity is much larger. Isolated impurities still have a symmetrical line shape, showing that the asymmetry is not due to inhomogeneities. Calculated line shapes by the coherent-potential-approximation technique are in very good qualitative agreement with the experimental results. The theory also accounts for previously published experimental data on the variations of the relative positions and intensities of the ortho and para peaks in (o-H2)x(p-H2)1-x.

de Kinder, J.; Bouwen, A.; Schoemaker, D.; Boukahil, A.; Huber, D. L.

1994-05-01

259

Molecularly imprinted polyaniline-polyvinyl sulphonic acid composite based sensor for para-nitrophenol detection.  

PubMed

We report results of the studies relating to the fabrication and characterization of a conducting polymer based molecularly imprinted para-nitrophenol (PNP) sensor. A water pollutant, para-nitrophenol is electrochemically imprinted with polyvinyl sulphonic acid (PVSA) doped polyaniline onto indium tin oxide (ITO) glass substrate. This PNP imprinted electrode (PNPI-PANI-PVSA/ITO) prepared via chronopotentiometric polymerization and over-oxidation is characterized by Fourier transform infra-red spectroscopy (FT-IR), UV-visible (UV-vis) spectroscopy, contact angle (CA), scanning electron microscopy (SEM), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies. The response studies of PNPI-PANI-PVSA/ITO electrode carried out using DPV reveal a lower detection limit of 1×10(-3) mM, improved sensitivity as 1.5×10(-3) A mM(-1) and stability of 45 days. The PNPI-PANI-PVSA/ITO electrode shows good precision with relative standard deviation of 2.1% and good reproducibility with standard deviation of 3.78%. PMID:23622966

Roy, Abhijit Chandra; Nisha, V S; Dhand, Chetna; Ali, Md Azahar; Malhotra, B D

2013-05-13

260

Screening electronic communication through ortho-, meta- and para-substituted linkers separating subphthalocyanines and C60.  

PubMed

We have prepared two complementary series of SubPc-C(60) (SubPc=subphthalocyanine) electron/energy donor-acceptor systems, in which the two constituents are linked through ortho-, meta-, or para-substituted phenoxy spacers. In one of the series (1 a) the SubPc units bear iodine atoms, while in the other series (1 b) diphenylamino groups are linked to the SubPc macrocycles. The iodine atoms and diphenylamino groups both influence the resulting oxidation potentials of the electron-donating SubPc. They also modulate the outcome of excited state interactions, namely, energy and/or charge transfer. In addition, we have studied the impact that the substitution pattern in the phenoxy spacer exerts onto intramolecular processes in the ground and excited states. Although some of these processes are governed by the spatial separation between both components, the different electronic coupling through ortho-, meta-, or para- connections also plays decisive roles in some cases. PMID:18624288

González-Rodríguez, David; Torres, Tomás; Herranz, María Angeles; Echegoyen, Luis; Carbonell, Esther; Guldi, Dirk M

2008-01-01

261

Rotational relaxation of CS by collision with ortho- and para-H2 molecules.  

PubMed

Quantum mechanical investigation of the rotationally inelastic collisions of CS with ortho- and para-H2 molecules is reported. The new global four-dimensional potential energy surface presented in our recent work is used. Close coupling scattering calculations are performed in the rigid rotor approximation for ortho- and para-H2 colliding with CS in the j = 0-15 rotational levels and for collision energies ranging from 10(-2) to 10(3) cm(-1). The cross sections and rate coefficients for selected rotational transitions of CS are compared with the ones previously reported for the collision of CS with He. The largest discrepancies are observed at low collision energy, below 1 cm(-1). Above 10 cm(-1), the approximation using the square root of the relative mass of the colliders to calculate the cross sections between a molecule and H2 from the data available with (4)He is found to be a good qualitative approximation. The rate coefficients calculated with the electron gas model for the He-CS system show more discrepancy with our accurate results. However, scaling up these rates by a factor of 2 gives a qualitative agreement. PMID:24289351

Denis-Alpizar, Otoniel; Stoecklin, Thierry; Halvick, Philippe; Dubernet, Marie-Lise

2013-11-28

262

Crystal dimension of ZSM-5 influences on para selective disproportionation of ethylbenzene.  

PubMed

Crystal size and crystal dimensions are vital role in shape selective feature. Para selective disproportionation of EthylBenzene (Dip-EB) was investigated over ZSM-5 synthesized in acidic medium. The catalysts were prepared by hydrothermal process with various Si/Al ratios (50, 75 and 100) using fluoride ion precursor. This fluoride ion precursor dissolves the ZSM-5 nutrients below it neutral pH between 4 and 6. The synthesized material was subjected into various physico chemical characterizations such as XRD, SEM, TGA and BET analyses. The XRD patterns showed high crystalline nature and their resulting SEM images were also indicate thin prismatic crystals of large dimension compared with alkaline medium synthesized one. The BET results earned good textural property. Catalytic activity of vapor phase Dip-EB was carried out between 523 and 673 K. As their result, diethylbenzene (DEB) isomers were obtained, but para selective Diethylbenzene (p-DEB) was observed higher than others. The high selectivity towards p-DEB was due to large crystal dimension of ZSM-5 catalysts synthesized in fluoride medium. Hence it is good commercial application for petrochemical feed stock production. PMID:24745253

Hariharan, Srinivasan; Palanichamy, Muthaiahpillai

2014-03-01

263

Photoinduced reactions of para-quinones with bicyclopropylidene leading to diverse polycyclic compounds with spirocyclopropanes.  

PubMed

Photoinduced reactions of bicyclopropylidene (BCP) with para-quinones (p-quinones) including benzoquinones, naphthoquinones, and anthraquinones were found to proceed via different cycloaddition pathways and lead to diverse polycyclic products bearing spiropropyl moiety. Photocycloaddition of BCP with benzoquinones gave spirooxetanes as the primary products, which upon irradiation were able to rearrange into the spiro[4.5]deca-6,9-diene-2,8-diones as secondary photoproducts. Chemoselectivity of the photocycloaddition of BCP with naphthoquinones relies largely on the substitution groups linked to the C?C in between the two carbonyl groups to give different types of products. Photoreaction of BCP with 9,10-anthraquinone gave not only the spirooxetane product, but also a novel spiro[indan-1,1'-phthalan]-3'-one product whose formation might be initiated by a transannular attack of the C4 cyclopropyl radical to the para-carbonyl group. Mechanisms involved in the formation of diverse primary or secondary products in the photoreactions of BCP with p-quinones were proposed. Some of the photoreactions also hold potentials as useful synthetic protocols for important spiropolycyclic compounds such as sesquiterpenes. PMID:23692405

Wang, Wei; Zhang, Wen-Jie; Wang, Lei; Quah, Ching Kheng; Fun, Hoong-Kun; Xu, Jian-Hua; Zhang, Yan

2013-06-21

264

Rotational relaxation of CS by collision with ortho- and para-H{sub 2} molecules  

SciTech Connect

Quantum mechanical investigation of the rotationally inelastic collisions of CS with ortho- and para-H{sub 2} molecules is reported. The new global four-dimensional potential energy surface presented in our recent work is used. Close coupling scattering calculations are performed in the rigid rotor approximation for ortho- and para-H{sub 2} colliding with CS in the j = 0–15 rotational levels and for collision energies ranging from 10{sup ?2} to 10{sup 3} cm{sup ?1}. The cross sections and rate coefficients for selected rotational transitions of CS are compared with the ones previously reported for the collision of CS with He. The largest discrepancies are observed at low collision energy, below 1 cm{sup ?1}. Above 10 cm{sup ?1}, the approximation using the square root of the relative mass of the colliders to calculate the cross sections between a molecule and H{sub 2} from the data available with {sup 4}He is found to be a good qualitative approximation. The rate coefficients calculated with the electron gas model for the He-CS system show more discrepancy with our accurate results. However, scaling up these rates by a factor of 2 gives a qualitative agreement.

Denis-Alpizar, Otoniel [Université de Bordeaux, ISM, UMR CNRS 5255, 33405 Talence (France) [Université de Bordeaux, ISM, UMR CNRS 5255, 33405 Talence (France); Departamento de Física, Universidad de Matanzas, Matanzas 40100 (Cuba); Stoecklin, Thierry, E-mail: t.stoecklin@ism.u-bordeaux1.fr; Halvick, Philippe [Université de Bordeaux, ISM, UMR CNRS 5255, 33405 Talence (France)] [Université de Bordeaux, ISM, UMR CNRS 5255, 33405 Talence (France); Dubernet, Marie-Lise [Université Pierre et Marie Curie, LPMAA, UMR CNRS 7092, 75252 Paris, France and Observatoire de Paris, LUTH, UMR CNRS 8102, 92195 Meudon (France)] [Université Pierre et Marie Curie, LPMAA, UMR CNRS 7092, 75252 Paris, France and Observatoire de Paris, LUTH, UMR CNRS 8102, 92195 Meudon (France)

2013-11-28

265

Ortho-to-para ratio in interstellar water on the sightline toward Sagittarius B2(N).  

PubMed

The determination of the water ortho-to-para ratio (OPR) is of great interest for studies of the formation and thermal history of water ices in the interstellar medium and protoplanetary disk environments. We present new Herschel observations of the fundamental rotational transitions of ortho- and para-water on the sightline toward Sagittarius B2(N), which allow improved estimates of the measurement uncertainties due to instrumental effects and assumptions about the excitation of water molecules. These new measurements, suggesting a spin temperature of 24-32 K, confirm the earlier findings of an OPR below the high-temperature value on the nearby sightline toward Sagittarius B2(M). The exact implications of the low OPR in the galactic center molecular gas remain unclear and will greatly benefit from future laboratory measurements involving water freeze-out and evaporation processes under low-temperature conditions, similar to those present in the galactic interstellar medium. Given the specific conditions in the central region of the Milky Way, akin to those encountered in active Galactic nuclei, gas-phase processes under the influence of strong X-ray and cosmic ray ionization also have to be carefully considered. We summarize some of the latest laboratory measurements and their implications here. PMID:23656468

Lis, Dariusz C; Bergin, Edwin A; Schilke, Peter; van Dishoeck, Ewine F

2013-10-01

266

Ortho-to-Para Ratio in Interstellar Water on the Sightline toward Sagittarius B2(N)  

NASA Astrophysics Data System (ADS)

The determination of the water ortho-to-para ratio (OPR) is of great interest for studies of the formation and thermal history of water ices in the interstellar medium and protoplanetary disk environments. We present new Herschel observations of the fundamental rotational transitions of ortho- and para-water on the sightline toward Sagittarius B2(N), which allow improved estimates of the measurement uncertainties due to instrumental effects and assumptions about the excitation of water molecules. These new measurements, suggesting a spin temperature of 24-32 K, confirm the earlier findings of an OPR below the high-temperature value on the nearby sightline toward Sagittarius B2(M). The exact implications of the low OPR in the galactic center molecular gas remain unclear and will greatly benefit from future laboratory measurements involving water freeze-out and evaporation processes under low-temperature conditions, similar to those present in the galactic interstellar medium. Given the specific conditions in the central region of the Milky Way, akin to those encountered in active Galactic nuclei, gas-phase processes under the influence of strong X-ray and cosmic ray ionization also have to be carefully considered. We summarize some of the latest laboratory measurements and their implications here.

Lis, Dariusz C.; Bergin, Edwin A.; Schilke, Peter; van Dishoeck, Ewine F.

2013-10-01

267

The new ParaDIgm: IgM from bench to clinic  

PubMed Central

The inaugural IgM event entitled “The new ParaDIgm: IgM from bench to clinic” brought together the increasingly active and growing IgM antibody community to discuss recent advances and challenges facing the discovery and development of IgM antibody therapies and technologies. Researchers, clinicians and biomanufacturing experts delivered 21 talks on the basic science and isolation of IgM, upstream and downstream development, and formulation and clinical development of the molecules. Participants networked around topics aimed at exploring the full potential of IgM antibodies. The meeting was held at DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e. V. (Society for Chemical Engineering and Biotechnology), a non-profit scientific and technical society based in Frankfurt am Main, Germany. The meeting was sponsored by Patrys, Laureate Biopharma, Bio-Rad Laboratories, BIA Separations, Percivia and the Bio Affinity Company (BAC). The second New ParaDIgm: IgM from bench to clinic meeting, will be held on April 23–24, 2013 in Frankfurt, Germany.

Hanala, Sherif

2012-01-01

268

Determination of the ortho to para ratio of H2Cl+ and H2O+ from submillimeter observations.  

PubMed

The opening of the submillimeter sky with the Herschel Space Observatory has led to the detection of new interstellar molecular ions, H2O(+), H2Cl(+), and HCl(+), which are important intermediates in the synthesis of water vapor and hydrogen chloride. In this paper, we report new observations of H2O(+) and H2Cl(+) performed with both Herschel and ground-based telescopes, to determine the abundances of their ortho and para forms separately and derive the ortho-to-para ratio. At the achieved signal-to-noise ratio, the observations are consistent with an ortho-to-para ratios of 3 for both H2O(+) and H2Cl(+), in all velocity components detected along the lines-of-sight to the massive star-forming regions W31C and W49N. We discuss the mechanisms that contribute to establishing the observed ortho-to-para ratio and point to the need for a better understanding of chemical reactions, which are important for establishing the H2O(+) and H2Cl(+) ortho-to-para ratios. PMID:23869910

Gerin, Maryvonne; de Luca, Massimo; Lis, Dariusz C; Kramer, Carsten; Navarro, Santiago; Neufeld, David; Indriolo, Nick; Godard, Benjamin; Le Petit, Franck; Peng, Ruisheng; Phillips, Thomas G; Roueff, Evelyne

2013-10-01

269

ORTHO-TO-PARA ABUNDANCE RATIO OF WATER ION IN COMET C/2001 Q4 (NEAT): IMPLICATION FOR ORTHO-TO-PARA ABUNDANCE RATIO OF WATER  

SciTech Connect

The ortho-to-para abundance ratio (OPR) of cometary molecules is considered to be one of the primordial characteristics of cometary ices, and contains information concerning their formation. Water is the most abundant species in cometary ices, and OPRs of water in comets have been determined from infrared spectroscopic observations of H{sub 2}O rovibrational transitions so far. In this paper, we present a new method to derive OPR of water in comets from the high-dispersion spectrum of the rovibronic emission of H{sub 2}O{sup +} in the optical wavelength region. The rovibronic emission lines of H{sub 2}O{sup +} are sometimes contaminated by other molecular emission lines but they are not affected seriously by telluric absorption compared with near-infrared observations. Since H{sub 2}O{sup +} ions are mainly produced from H{sub 2}O by photoionization in the coma, the OPR of H{sub 2}O{sup +} is considered to be equal to that of water based on the nuclear spin conservation through the reaction. We have developed a fluorescence excitation model of H{sub 2}O{sup +} and applied it to the spectrum of comet C/2001 Q4 (NEAT). The derived OPR of water is 2.54{sup +0.32}{sub -0.25}, which corresponds to a nuclear spin temperature (T{sub spin}) of 30{sup +10}{sub -4} K. This is consistent with the previous value determined in the near-infrared for the same comet (OPR = 2.6 {+-} 0.3, T{sub spin} = 31{sup +11}{sub -5} K).

Shinnaka, Yoshiharu; Kawakita, Hideyo; Kobayashi, Hitomi [Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Boice, Daniel C.; Martinez, Susan E. [Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238 (United States)

2012-04-20

270

Compilação de dados atômicos e moleculares do UV ao IV próximo para uso em síntese espectral  

NASA Astrophysics Data System (ADS)

Espectros sintéticos são utéis em uma grande variedade de aplicações, desde análise de abundâncias em espectros estelares de alta resolução ao estudo de populações estelares em espectros integrados. A confiabilidade de um espectro sintético depende do modelo de atmosfera adotado, do código de formação de linhas e da qualidade dos dados atômicos e moleculares que são determinantes no cálculo das opacidades da fotosfera. O nosso grupo no departamento de Astronomia no IAG tem utilizado espectros sintéticos há mais de 15 anos, em aplicações voltadas principalmente para a análise de abundâncias de estrelas G, K e M e populações estelares velhas. Ao longo desse tempo, as listas de linhas vieram sendo construídas e atualizadas continuamente, e alguns acréscimos recentes podem ser citados: Castilho (1999, átomos e moléculas no UV), Schiavon (1998, bandas moleculares de TiO) e Melendez (2001, átomos e moléculas no IV próximo). Com o intuito de calcular uma grade de espectros do UV ao IV próximo para uso no estudo de populações estelares velhas, se fazia necessário compilar e homogeneizar as diversas listas em apenas uma lista atômica e uma molecular. Nesse processo, a nova lista compilada foi correlacionada com outras bases de dados (NIST, Kurucz Database, O' Brian et al. 1991) para atualização dos parâmetros que caracterizam a transição atômica (comprimento de onda, log gf e potencial de excitação). Adicionalmente as constantes de interação C6 foram calculadas segundo a teoria de Anstee & O'Mara (1995) e artigos posteriores. As bandas moleculares de CH e CN foram recalculadas com o programa LIFBASE (Luque & Crosley 1999). Nesse poster estão detalhados os procedimentos citados acima, as comparações entre espectros calculados com as novas listas e espectros observados em alta resolução do Sol e de Arcturus, e uma análise do impacto decorrente da utilização de diferentes modelos de atmosfera no espectro sintético. Ao final, temos uma lista de linhas atômicas com mais de 24.000 linhas e uma lista molecular com as moléculas CN, CH, OH, NH, MgH, C2, TiO Gama, CO, FeH, adequadas ao estudo de estrelas G, K e M e populações estelares velhas.

Coelho, P.; Barbuy, B.; Melendez, J.; Allen, D. M.; Castilho, B.

2003-08-01

271

Passivation of iron-based alloys in para-toluene sulfonic acid  

SciTech Connect

Potentiodynamic and surface analysis techniques were applied to investigate the passivation of metals in para-toluene sulfonic acids (PTSA). The diffusion-limiting current density was used to calculate the ferrous ion concentration which causes the precipitation of a pseudopassive film. From the surface analysis data, the Cr/Fe ratio in the passive film increases in order of 430, 304, and 316 stainless steels. To analyze the differences, a correction was made to the data so that the observed difference in the oxide film composition is not attributed simply to the Cr and Fe contents of the alloys. This method also was applied to correct the Ni/Fe ratio in the passive film. The authors conclude that the preferential dissolution of Ni and Fe leads to a Cr enrichment in the passive film.

Iuan Jou Yang; Mao Ying Teng (Materials Research Labs., Chutung, Hsinchu (Taiwan, Province of China))

1993-06-01

272

Quantum dynamical simulations for nuclear spin selective laser control of ortho- and para-fulvene  

NASA Astrophysics Data System (ADS)

In the present paper we explore the prospects for laser control of the photoinduced nonadiabatic dynamics of para- and ortho-fulvene with the help of quantum dynamical simulations. Previous investigations [Bearpark et al., J. Am. Chem. Soc. 118, 5253 (1996); Alfalah et al., J. Chem. Phys. 130, 124318 (2009)] show that photoisomerization of fulvene is hindered by ultrafast radiationless decay through a conical intersection at planar configuration. Here, we demonstrate that photoisomerization can nevertheless be initiated by damping unfavorable nuclear vibrations with properly designed laser pulses. Moreover, we show that the resulting intramolecular torsion is nuclear spin selective. The selectivity of the photoexcitation with respect to the nuclear spin isomers can be further enhanced by applying an optimized sequence of two laser pulses.

Belz, S.; Grohmann, T.; Leibscher, M.

2009-07-01

273

El Proyecto Sismico "LARSE" - Trabajando Hacia un Futuro con Mas Seguridad para Los Angeles  

USGS Publications Warehouse

La region de Los Angeles contiene una red de fallas activas, incluyendo muchas fallas por empuje que son profundas y no rompen la superficie de la tierra. Estas fallas ocultas incluyen la falla anteriormente desconocida que fue responsable por la devastacion que ocurrio durante el terremoto de Northridge en enero de 1994, el terremoto mas costoso en la historia de los Estados Unidos. El Experimento Sismico en la Region de Los Angeles (Los Angeles Region Seismic Experiment, LARSE), esta localizando los peligros ocultos de los terremotos debajo de la region de Los Angeles para mejorar la construccion de las estructuras que pueden apoyar terremotos que son inevitables en el futuro, y que ayudaran a los cientificos determinar donde occurira el sacudimento mas fuerte y poderoso.

Henyey, Thomas L.; Fuis, Gary S.; Benthien, Mark L.; Burdette, Thomas R.; Christofferson, Shari A.; Clayton, Robert W.; Criley, Edward E.; Davis, Paul M.; Hendley, James W., II; Kohler, Monica D.; Lutter, William J.; McRaney, John K.; Murphy, Janice M.; Okaya, David A.; Ryberg, Trond; Simila, Gerald W.; Stauffer, Peter H.

1999-01-01

274

Transient effects and pump depletion in stimulated Raman scattering. [Para-hydrogen  

SciTech Connect

Stimulated rotational Raman scattering in a 300-K multipass cell filled with para-H/sub 2/ with a single-mode CO/sub 2/-pumped laser is studied using a frequency-narrowed optical parametric oscillator (OPO) as a probe laser at the Stokes frequency for the S/sub 0/(O) transition. Amplification and pump depletion are examined as a function of incident pump energy. The pump depletion shows clear evidence of transient behavior. A theoretical treatment of transient stimulated Raman scattering, including effects of both pump depletion and medium saturation is presented. In a first approximation, diffraction effects are neglected, and only plane-wave interactions are considered. The theoretical results are compared to the experimental pulse shapes.

Carlsten, J.L.; Wenzel, R.G.; Druehl, K.

1983-01-01

275

Cholecystocutaneous fistula: an unusual complication of a para-umbilical hernia repair.  

PubMed

This case describes a 94-year-old woman who presented 2?years postsutured para-umbilical hernia repair with a painful black lump protruding through her scar with blood stained discharge. This was initially thought to be either ischaemic bowel secondary to strangulated incisional hernia or a large organised haematoma. An urgent CT scan was performed following which the patient passed two large calculi and bile-stained fluid spontaneously through the wound, making the diagnosis somewhat clearer. The scan revealed an incisional hernia containing the gallbladder and two large calculi at the skin surface and an incidental large caecal cancer with surrounding lymphadenopathy. Frail health and the incidental finding of a colon cancer rendered invasive surgical management inappropriate. Therefore, she was managed conservatively with antibiotics. A catheter was inserted into the fistula tract to allow free drainage and alleviate pressure-related symptoms. The patient was discharged following a multidisciplinary team discussion. PMID:24862413

Dixon, Steven; Sharma, Mitesh; Holtham, Stephen

2014-01-01

276

Puncture injection of para-toluenesulfonamide combined with chemoembolization for advanced hepatocellular carcinoma  

PubMed Central

Hepatocellular carcinoma (HCC) is difficult to eradicate due to its resilient nature. Portal vein is often involved in tumors of large size, which exclude the patient from surgical resection and local ablative therapy, such as percutaneous ethanol injection (PEI) and radiofrequency ablation (RFA) because they were considered neither effective nor safe. Currently, there is almost no effective treatment for HCC of such condition. As a unique antitumor agent in form of lipophilic fluid for local injection, para-toluenesulfonamide (PTS) produces mild side effects while necrotizing the tumor tissues quickly and efficiently. Being largely different from both PEI and RFA therapies, PTS can disseminate itself in tumors more easily than other caustic agents, such as alcohol. So PTS may offer additional benefit to HCCs with vascular involvement. We herein describe a 70-year-old HCC patient who was treated with the combination of PTS injection and transcatheter arterial chemoembolization, resulting in a significantly improved clinical prognosis.

He, Qing; Kuang, An-Ren; Guan, Yong-Song; Liu, Yue-Qing

2012-01-01

277

Searching for auxetics with DYNA3D and ParaDyn  

NASA Astrophysics Data System (ADS)

We sought to simulate auxetic behavior by carrying out dynamic analyses of mesoscopic model structures. We began by generating nearly periodic cellular structures. Four-node Shell elements and eight-node Brick elements are the basic building blocks for each cell. The shells and bricks obey standard elastic-plastic continuum mechanics. The dynamical response of the structures was next determined for a three-stage loading process: (1) homogeneous compression; (2) viscous relaxation; (3) uniaxial compression. The simulations were carried out with both serial and parallel computer codes - DYNA3D and ParaDyn - which describe the deformation of the shells and bricks with a robust contact algorithm. We summarize the results found here.

Hoover, Wm. G.; Hoover, C. G.

2005-03-01

278

Adsorption and organisation of para-hexaphenyl molecules on Si(100)  

NASA Astrophysics Data System (ADS)

Para-hexaphenyl molecules (p-6P: C36H26) can be grown as nanofibres on various surfaces having optical properties of technological relevance. We report here the first observations of the initial stages of adsorption of individual p-6P molecules on Si(100)-(2×1) using room temperature Scanning Tunnelling Microscopy (STM). Depending on the substrate temperature, the hexaphenyl molecules adsorb in two configurations; indicating both weak and strong chemisorption. All six phenyl rings are clearly visible and the molecules are found to adsorb with characteristic angles between the long axis of the molecule and the silicon dimer rows. A statistical analysis of the spatial distribution of the molecules suggests that the clustering required for crystallographic nanofibre growth does not occur at the atomic scale under the experimental conditions used here.

Cranney, M.; Chalopin, Y.; Mayne, A. J.; Dujardin, G.

2009-03-01

279

Food for Life / Comida para la Vida: creating a food festival to raise diabetes awareness.  

PubMed

African and Latino Americans have higher rates of diabetes and its complications than White Americans. Identifying people with undiagnosed diabetes and helping them obtain care can help to prevent complications and mortality. To kick off a screening initiative, our community-academic partnership created the "Food for Life Festival," or "Festival Comida para la Vida." This article will describe the community's perspective on the Festival, which was designed to screen residents, and demonstrate that eating healthy can be fun, tasty, and affordable in a community-centered, culturally consonant setting. More than 1,000 residents attended the event; 382 adults were screened for diabetes, and 181 scored as high risk. Fifteen restaurants distributed free samples of healthy versions of their popular dishes. Community residents, restaurateurs, and clinicians commented that the event transformed many of their preconceived ideas about healthy foods and patient care. PMID:20097997

Lancaster, Kristie; Walker, Willie; Vance, Thomas; Kaskel, Phyllis; Arniella, Guedy; Horowitz, Carol

2009-01-01

280

Pair potentials and equation of state of solid para-hydrogen to megabar pressure  

NASA Astrophysics Data System (ADS)

We compute by means of quantum Monte Carlo simulations the equation of state of bulk solid para-hydrogen extrapolated to zero temperature, up to a pressure of ˜2 Mbar. We compare the equation of state yielded by three different pair potentials, namely, the Silvera-Goldman (SG), Buck, and one recently proposed by Moraldi, modified at short distances to include a repulsive core, missing in the originally proposed potential. The Moraldi pair potential yields an equation of state in very good agreement with experiment at megabar pressures, owing to its softer core, and is at least as accurate as the SG or the Buck at saturated vapor pressure. Estimates for the experimentally measurable kinetic energy per molecule are provided for all pair potentials.

Omiyinka, Tokunbo; Boninsegni, Massimo

2013-07-01

281

Effect of alpha-methyl-para-tyrosine on response to cocaine challenge.  

PubMed

This study evaluated the effect of an acute reduction in catecholamine synthesis produced by alpha-methyl-para-tyrosine (AMPT), a tyrosine hydroxylase inhibitor, on cocaine-induced euphoria. In a blinded, placebo-controlled study, AMPT (1 g p.o. T.I.D.) was given to 10 non-treatment-seeking cocaine abusers prior to intranasal administration of 2 mg/kg cocaine. AMPT, but not placebo, reduced plasma levels of the dopamine metabolite homovanillic acid and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol. AMPT also elevated prolactin levels, indicating inhibition of the tuberoinfundibular dopamine system. AMPT pretreatment produced a trend toward diminished cocaine "high" AMPT also tended to lower heart rate and blood pressure responses to cocaine, but had no effect on serum cocaine levels. Although we cannot rule out the therapeutic potential of the depletion strategy, our results with AMPT alone, at this dose, do not strongly support it. PMID:9232210

Stine, S M; Krystal, J H; Petrakis, I L; Jatlow, P I; Heninger, G R; Kosten, T R; Charney, D S

1997-08-01

282

Ortho/para ratio of H2O+ toward Sagittarius B2(M) revisited.  

PubMed

The HIFI instrument aboard the Herschel satellite has allowed the observation and characterization of light hydrides, the building blocks of interstellar chemistry. In this article, we revisit the ortho/para ratio for H2O(+) toward the Sgr B2(M) cloud core. The line of sight toward this star forming region passes through several spiral arms and the gas in the Bar potential in the inner Galaxy. In contrast to earlier findings, which used fewer lines to constrain the ratio, we find a ratio of 3, which is uniformly consistent with high-temperature formation of the species. In view of the reactivity of this ion, this matches the expectations. PMID:23713712

Schilke, Peter; Lis, Dariusz C; Bergin, Edwin A; Higgins, Ronan; Comito, Claudia

2013-10-01

283

Surface treatment of para-aramid fiber by argon dielectric barrier discharge plasma at atmospheric pressure  

NASA Astrophysics Data System (ADS)

This paper is focused on influence of argon dielectric barrier discharge (DBD) plasma on the adhesive performance and wettability of para-aramid fibers and three parameters including treated power, exposure time and argon flux were detected. The interfacial shear strength (IFSS) was greatly increased by 28% with 300 W, 60 s, 2 L min-1 argon flux plasma treatment. The content of oxygen atom and oxygen-containing polar functional groups were enhanced after the argon plasma treated, so as the surface roughness, which contributed to the improvement of surface wettability and the decrease of contact angle with water. However, long-time exposure, exorbitant power or overlarge argon flux could partly destroy the prior effects of the treatment and damage the mechanical properties of fibers to some degree.

Gu, Ruxi; Yu, Junrong; Hu, Chengcheng; Chen, Lei; Zhu, Jing; Hu, Zuming

2012-10-01

284

Unusual Raman spectra of para-nitroaniline by sequential Fermi resonances.  

PubMed

In this communication, we report the unusual Raman spectra of para-nitroaniline (PNA) by sequential Fermi resonances. The combinational mode 1292 cm(-1) in the experimental Raman spectrum indirectly gains the initial spectral weight at 1392 cm(-1) by three sequential Fermi resonances. These Fermi resonances result in the strong interaction between the donor group of NH2 and the acceptor group of NO2. Our theoretical calculations provide reasonable interpretation for the abnormal Raman spectra of PNA. Experimental surface enhanced Raman scattering (SERS) spectrum of PNA further confirmed our conclusion, where the strongest Raman peak at 1292 cm(-1) is very weak, while the Raman peak at 1392 cm(-1) becoming the strongest Raman peak, which is consistent with the theoretical simulations. PMID:24370347

Xia, Jiarui; Zhu, Ling; Feng, Yanting; Li, Yongqing; Zhang, Zhenglong; Xia, Lixin; Liu, Liwei; Ma, Fengcai

2014-02-24

285

Poly(para-dioxanone)/inorganic particle composites as a novel biomaterial.  

PubMed

In this work, poly(para-dioxanone) (PPDO) was mixed with 1% (by weight) calcium carbonate (CaCO(3)), beta-tricalcium phosphate (beta-TCP), or calcium sulphate dihydrate (CSD) by solution co-precipitation. Samples were compression molded into bars using a platen-vulcanizing press. The morphology, thermal and mechanical properties, and crystalline structure of the composites were investigated using differential scanning calorimetry, polarized optical microscopy, scanning electron microscopy, and X-ray diffraction. All results suggest that three types of inorganic particle in this system promote the crystallinity of PPDO and act as an effective nucleating agent: the relative degree of crystallinity of PPDO increased from 30.74% to 100%, and the crystallization temperature of PPDO was increased by 18 degrees C. On the other hand, the mechanical properties of PPDO were changed by the presence of inorganic particles: the tensile strength of PPDO/CSD increased by 11.46%. PMID:19360890

Bai, Wei; Chen, Dongliang; Zhang, Zhiping; Li, Qing; Zhang, Dujuan; Xiong, Chengdong

2009-08-01

286

Rotational Spectroscopy of Carbon Monoxide Solvated with Para-Hydrogen Molecules  

NASA Astrophysics Data System (ADS)

Rotational spectra of carbon monoxide (^{12}C^{16}O and ^{13}C^{16}O) solvated with N=2 to 7 para-hydrogen (pH_2) molecules were studied by high resolution Fourier transform microwave spectroscopy. Infrared spectra of (pH_2)_N-CO clusters have previously been reported by Moroni et al. It is expected that the end-over-end rotational frequency decreases from N=2 to N=6, then increases with the addition of the next several helium atoms; this could indicate a significant decoupling of pH_2 density from CO rotation. By measuring the microwave transitions of these clusters we are able to separate the rotational and vibrational contributions to the rovibrational line positions. The trend of the pure rotational frequencies with increasing N-value will be presented. S. Moroni, M. Botti, S. De Palo, A. R. W. McKellar, J. Chem. Phys., 122, 094314 (2005).

Raston, Paul L.; Jäger, Wolfgang

2009-06-01

287

Determination of para red, Sudan dyes, canthaxanthin, and astaxanthin in animal feeds using UPLC.  

PubMed

A simple high-performance liquid chromatography method was developed for quantitative determination of para red, Sudan I, Sudan II, Sudan III, Sudan IV, canthaxanthin, and astaxanthin in feedstuff. The sample was extracted using acetonitrile and cleaned up on a C(18) SPE column. The residues were analyzed using ultra-performance liquid chromatography coupled to a diode array detector at 500 nm. The mobile phase was acetonitrile-formic acid-water with a gradient elution condition. The external standard curves were calibrated. The mean recoveries of the seven colorants were 62.7-91.0% with relative standard deviation 2.6-10.4% (intra-day) and 4.0-13.2% (inter-day). The detection limits were in the range of 0.006-0.02 mg/kg. PMID:20056031

Hou, Xiaolin; Li, Yonggang; Wu, Guojuan; Wang, Lei; Hong, Miao; Wu, Yongnin

2010-01-01

288

The Rayleigh-Taylor instability in quantum magnetized plasma with para- and ferromagnetic properties  

SciTech Connect

We investigate influence of magnetic field on the Rayleigh-Taylor instability in quantum plasmas with para- and ferromagnetic properties. Magnetization of quantum plasma happens due to the collective electron spin behavior at low temperature and high plasma density. In the classical case, without magnetization, magnetic field tends to stabilize plasma perturbations with wave numbers parallel to the field and with sufficiently short wavelengths. Paramagnetic effects in quantum plasma make this stabilization weaker. The stabilization disappears completely for short wavelength perturbations in the ferromagnetic limit, when the magnetic field is produced by intrinsic plasma magnetization only. Still, for perturbations of long and moderate wavelength, certain stabilization always takes place due to the nonlinear character of quantum plasma magnetization.

Modestov, Mikhail; Bychkov, Vitaly; Marklund, Mattias [Department of Physics, Umeaa University, 901 87 Umeaa (Sweden)

2009-03-15

289

The analysis of para-cresol production and tolerance in Clostridium difficile 027 and 012 strains  

PubMed Central

Background Clostridium difficile is the major cause of antibiotic associated diarrhoea and in recent years its increased prevalence has been linked to the emergence of hypervirulent clones such as the PCR-ribotype 027. Characteristically, C. difficile infection (CDI) occurs after treatment with broad-spectrum antibiotics, which disrupt the normal gut microflora and allow C. difficile to flourish. One of the relatively unique features of C. difficile is its ability to ferment tyrosine to para-cresol via the intermediate para-hydroxyphenylacetate (p-HPA). P-cresol is a phenolic compound with bacteriostatic properties which C. difficile can tolerate and may provide the organism with a competitive advantage over other gut microflora, enabling it to proliferate and cause CDI. It has been proposed that the hpdBCA operon, rarely found in other gut microflora, encodes the enzymes responsible for the conversion of p-HPA to p-cresol. Results We show that the PCR-ribotype 027 strain R20291 quantitatively produced more p-cresol in-vitro and was significantly more tolerant to p-cresol than the sequenced strain 630 (PCR-ribotype 012). Tyrosine conversion to p-HPA was only observed under certain conditions. We constructed gene inactivation mutants in the hpdBCA operon in strains R20291 and 630?erm which curtails their ability to produce p-cresol, confirming the role of these genes in p-cresol production. The mutants were equally able to tolerate p-cresol compared to the respective parent strains, suggesting that tolerance to p-cresol is not linked to its production. Conclusions C. difficile converts tyrosine to p-cresol, utilising the hpdBCA operon in C. difficile strains 630 and R20291. The hypervirulent strain R20291 exhibits increased production of and tolerance to p-cresol, which may be a contributory factor to the virulence of this strain and other hypervirulent PCR-ribotype 027 strains.

2011-01-01

290

Prevalence of oral trauma in Para-Pan American Games athletes.  

PubMed

The aim of this cross-sectional epidemiological survey was to assess the prevalence of oral trauma in athletes representing 25 countries competing at the most recent Para-Pan American Games (III PARAPAN) held in Rio de Janeiro, Brazil. The study was approved by the appropriate institutional review board. The examiners participated in standardization and calibration training sessions before the field phase began. Invitations were sent to >1200 participating athletes competing in eight sports and to the Medical Committee of the Para-Pan American Sports Organization before and during the III PARAPAN. A convenience sample of 120 athletes was recruited. After signing an informed consent, all athletes answered a questionnaire. Data were collected at the clinical examination and recorded in a specific trauma form. The mean age of the athletes was 32.5 years. Males comprised 79.2% of the sample; females 20.8%. The prevalence of oral trauma among the athletes was 47.5% (N = 57). However, only 15 athletes reported that these traumatic injuries were sports-related. The sport with the highest prevalence of oral trauma was judo (75%); the least was volleyball with no reported traumatic injuries. The most common traumatic injury was enamel fracture (27.4%). The teeth most affected were the maxillary permanent central incisors (N = 19), followed by the maxillary premolars (N = 8). On the basis of the results of this study of oral trauma among athletes examined at the III PARAPAN, a recommendation for enhanced educational efforts and the use of properly fitted mouthguards to prevent traumatic injuries among high-performance athletes with disabilities seems warranted. PMID:22882839

Andrade, Rafaela Amarante; Modesto, Adriana; Evans, Patricia Louise Scabell; Almeida, Anne Louise Scabell; da Silva, Juliana de Jesus Rodrigues; Guedes, Aurelino Machado Lima; Guedes, Fábio Ribeiro; Ranalli, Dennis N; Tinoco, Eduardo Muniz Barretto

2013-08-01

291

Salud para su Corazón: a community-based Latino cardiovascular disease prevention and outreach model.  

PubMed

Cardiovascular disease (CVD) is the leading cause of death for Latinos living in the United States. This population is generally unaware of important lifestyle or behavioral changes that can prevent CVD. The National Heart, Lung, and Blood Institute (NHLBI) designed and implemented Salud para su Corazón (Health for Your Heart), a culturally appropriate, community-based, theory-driven intervention model. NHLBI's goals were: (1) to design an intervention model appropriate to Latino populations; (2) to pilot test the model in a specific community with the objectives of increasing awareness about heart disease, raising knowledge about CVD prevention, and promoting heart-healthy lifestyles; and (3) to disseminate the model and the materials developed to other communities with similar needs. An agency-community partnership, under the leadership of the Community Alliance for Heart Health, guided all stages of the community intervention project. The multimedia bilingual community intervention included television telenovela format public service announcements (PSAs), radio programs, brochures, recipe booklets, charlas, a promotores training manual, and motivational videos. An evaluation survey assessed the impact of the intervention. A pre-post intervention survey was conducted with more than 300 participants, and results showed that the respondents were substantially more aware of risk factors for CVD, and had greatly increased their knowledge of ways to prevent heart disease. Dissemination efforts have resulted in numerous requests by health organizations, universities, and health maintenance organizations (HMOs) for educational materials and communication strategies produced by Salud para su Corazón. In addition, Univision, the largest Spanish-language broadcast television network, is airing the initiative's PSAs. Also, training seminars for promotores are being conducted in different regions of the United States, and several locations are planning to replicate this study. PMID:10555925

Alcalay, R; Alvarado, M; Balcazar, H; Newman, E; Huerta, E

1999-10-01

292

Self-assembled catalytic DNA nanostructures for synthesis of para-directed polyaniline.  

PubMed

Templated synthesis has been considered as an efficient approach to produce polyaniline (PANI) nanostructures. The features of DNA molecules enable a DNA template to be an intriguing template for fabrication of emeraldine PANI. In this work, we assembled HRP-mimicking DNAzyme with different artificial DNA nanostructures, aiming to manipulate the molecular structures and morphologies of PANI nanostructures through the controlled DNA self-assembly. UV-vis absorption spectra were used to investigate the molecular structures of PANI and monitor kinetic growth of PANI. It was found that PANI was well-doped at neutral pH and the redox behaviors of the resultant PANI were dependent on the charge density of the template, which was controlled by the template configurations. CD spectra indicated that the PANI threaded tightly around the helical DNA backbone, resulting in the right handedness of PANI. These reveal the formation of the emeraldine form of PANI that was doped by the DNA. The morphologies of the resultant PANI were studied by AFM and SEM. It was concluded from the imaging and spectroscopic kinetic results that PANI grew preferably from the DNAzyme sites and then expanded over the template to form 1D PANI nanostructures. The strategy of the DNAzyme-DNA template assembly brings several advantages in the synthesis of para-coupling PANI, including the region-selective growth of PANI, facilitating the formation of a para-coupling structure and facile regulation. We believe this study contributes significantly to the fabrication of doped PANI nanopatterns with controlled complexity, and the development of DNA nanotechnology. PMID:23272944

Wang, Zhen-Gang; Zhan, Pengfei; Ding, Baoquan

2013-02-26

293

Observation of Ortho-Para {bold H}{sup {bold +}}{sub {bold 3}} Selection Rules in Plasma Chemistry  

SciTech Connect

Intensity ratios of infrared spectral lines of ortho- and para-H{sup +}{sub 3} have been measured in hydrogen plasmas using normal and para-H{sub 2}. Large dependences of the intensity ratios on the parent gases have been observed, indicating the spin memory of protons even after chemical reactions. The results clearly demonstrate the existence of selection rules on nuclear spin modifications in chemical reactions theoretically anticipated by M. Quack[Mol.Phys.{bold 34}, 477 (1977)]. {copyright} {ital 1997} {ital The American Physical Society}

Uy, D.; Cordonnier, M.; Oka, T. [Department of Chemistry and Department of Astronomy and Astrophysics, The Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637 (United States)] [Department of Chemistry and Department of Astronomy and Astrophysics, The Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637 (United States)

1997-05-01

294

A kinetic method for para -nitrophenol determination based on its inhibitory effect on the catalatic reaction of catalase  

Microsoft Academic Search

The inhibitory effect of para-nitrophenol on the catalytic reaction of catalase was investigated. Michaelis-Menten kinetic parameters were determined from\\u000a Lineweaver-Burk plots obtained in the absence or in the presence of the inhibitor. The inhibitor pattern, revealed by the\\u000a Lineweaver-Burk plots, suggested a fully mixed inhibition mechanism. Spectrophotometric monitoring of the indicator reaction:\\u000a $$H_2 O_2 \\\\xrightarrow{{catalase,para - nitrophenol}}H_2 O + \\\\tfrac{1}{2}O_2

Claudia Mure?anu; Lucian Copolovici; Florina Pogùacean

2005-01-01

295

Chlorination of 2-phenoxypropanoic acid with NCP in aqueous acetic acid: using a novel ortho-para relationship and the para/meta ratio of substituent effects for mechanism elucidation.  

PubMed

Rate constants were measured for the oxidative chlorodehydrogenation of (R,S)-2-phenoxypropanoic acid and nine ortho-, ten para- and five meta-substituted derivatives using (R,S)-1-chloro-3-methyl-2,6-diphenylpiperidin-4-one (NCP) as chlorinating agent. The kinetics was run in 50% (v/v) aqueous acetic acid acidified with perchloric acid under pseudo-first-order conditions with respect to NCP at temperature intervals of 5 K between 298 and 318 K, except at the highest temperature for the meta derivatives. The dependence of rate constants on temperature was analyzed in terms of the isokinetic relationship (IKR). For the 20 reactions studied at five different temperatures, the isokinetic temperature was estimated to be 382 K, which suggests the preferential involvement of water molecules in the rate-determining step. The dependence of rate constants on meta and para substitution was analyzed using the tetralinear extension of the Hammett equation. The parameter lambda for the para/meta ratio of polar substituent effects was estimated to be 0.926, and its electrostatic modeling suggests the formation of an activated complex bearing an electric charge near the oxygen atom belonging to the phenoxy group. A new approach is introduced for examining the effect of ortho substituents on reaction rates. Using IKR-determined values of activation enthalpies for a set of nine pairs of substrates with a given substituent, a linear correlation is found between activation enthalpies of ortho and para derivatives. The correlation is interpreted in terms of the selectivity of the reactant toward para- or ortho-monosubstituted substrates, the slope of which being related to the ortho effect. This slope is thought to be approximated by the ratio of polar substituent effects from ortho and para positions in benzene derivatives. Using the electrostatic theory of through-space interactions and a dipole length of 0.153 nm, this ratio was calculated at various positions of a charged reaction center along the benzene C1-C4 axis, being about 2.5 near the ring and decreasing steeply with increasing distance until reaching a minimum value of -0.565 at 1.3 nm beyond the aromatic ring. Activation enthalpies and entropies were estimated for substrates bearing the isoselective substituent in either ortho and para positions, being demonstrated that they are much different from the values for the parent substrate. The electrophilic attack on the phenolic oxygen atom by the protonated chlorinating agent is proposed as the rate-determining step, this step being followed by the fast rearrangement of the intermediate thus formed, leading to products containing chlorine in the aromatic ring. PMID:17567074

Segurado, Manuel A P; Reis, João Carlos R; de Oliveira, Jaime D Gomes; Kabilan, Senthamaraikannan; Shanthi, Manohar

2007-07-01

296

Ortho- and para-selective ruthenium-catalyzed C(sp2)-H oxygenations of phenol derivatives.  

PubMed

Versatile ruthenium catalysts allowed for efficient direct oxygenations of aryl carbamates under remarkably mild reaction conditions. In addition to chelation-assisted C-H activation, the optimized ruthenium catalyst proved amenable to para-selective hydroxylations of anisoles without Lewis basic directing groups. PMID:23799802

Liu, Weiping; Ackermann, Lutz

2013-07-01

297

ParaMEME: a parallel implementation and a web interface for a DNA and protein motif discovery tool.  

PubMed

Many advanced software tools fail to reach a wide audience because they require specialized hardware, installation expertise, or an abundance of CPU cycles. The worldwide web offers a new opportunity for distributing such systems. One such program, MEME, discovers repeated patterns, called motifs, in sets of DNA or protein sequences. This tool is now available to biologists over the worldwide web, using an asynchronous, single-program multiple-data version of the program called ParaMEME that runs on an Intel Paragon XP/S parallel computer at the San Diego Super-computer Center. ParaMEME scales gracefully to 64 nodes on the Paragon with efficiencies > 72% for large data sets. The worldwide web interface to ParaMEME accepts a set of sequences interactively from a user, submits the sequences to the Paragon for analysis, and e-mails the results back to the user. ParaMEME is available for free public use at http://@www.sdsc.edu/CompSci/Biomed/ MEME. PMID:8902357

Grundy, W N; Bailey, T L; Elkan, C P

1996-08-01

298

Effect of Stress and Para-Chlorophenylalanine Upon Brain Serotonin, 5-Hydroxyindoleacetic Acid and Catecholamines in Grouped and Isolated Mice.  

National Technical Information Service (NTIS)

Para-chlorophenylalanine (pCpA), administered to mice only a few hours before they were sacrificed, lowered whole brain serotonin (5-HT) only slightly but caused a marked (27%) reduction in 5-hydroxyindoleacetic acid (5-HIAA). Restraint stress for 2.75 hr...

A. S. Welch B. L. Welch

1967-01-01

299

Acuerdos entre el gobierno central y los departamentos: una propuesta para aumentar la eficiencia del gasto público  

Microsoft Academic Search

El objetivo de este trabajo es proponer un instrumento para el seguimiento de la eficiencia del gasto público. El instrumento muestra que el gobierno central se puede apoyar en las administraciones departamentales con el fin de medir los productos del gasto. La idea central de la propuesta es que los objetivos de productividad acordados entre el nivel nacional y el

Isaac de León-Beltrán; Diego Jaramillo

2006-01-01

300

Una Metodología para Ajustar y Compensar las Diferencias de Riesgo entre el Sistema Público y Privado de Salud en Chile  

Microsoft Academic Search

En el marco conceptual de seguros de salud y ajuste de riesgo y a la luz de la experiencia internacional en Fondos de Compensación de Riesgos, este documento explora el problema del «descreme» que afecta al sistema de seguros Chileno. Se presenta una metodología para estimar diferencias de riesgo entre el sector público y privado de salud en Chile y

Verónica Vargas; Camilo Cid; Mauricio Matus; Iris Delgado; José Miguel Sánchez; Beatriz Heyermann; José Angulo

301

La valoraciòn econòmica de bienes y servicios ambientales como herramienta estrategica para la conservaciòn y uso sostenible de los ecosistemas  

Microsoft Academic Search

Resumen El trabajo corresponde a un estudio piloto hacia la implementación de una metodología que permita aproximar el valor monetario de los Bienes y Servicios Ambientales (BSA) ofertados por un ecosistema hídrico, caso “Ciénaga de la Caimanera, municipio de Coveñas, departamento de Sucre-Colombia”, como herramienta estratégica para incentivar la conservación y uso sostenible de los ecosistemas. Avanzar en procesos de

ADOLFO CARBAL HERRERA

2010-01-01

302

Custos de alimentação para caprinos na fase de aleitamento recebendo sucedâneos com fontes de proteína láctea e de origem vegetal  

Microsoft Academic Search

5 Bolsista de Pós-doutorado da Fapemig, UFV, Viçosa - MG. Resumo: Leite em pó integral de vaca, reconstituído, e sucedâneo comercial à base de mistura de proteínas vegetais isoladas foram comparados para avaliar custo de produção no aleitamento artificial em caprinos. Os animais foram separados das mães logo após o nascimento recebendo colostro tratado nas primeiras 6 horas de vida.

Ana Gabriela Pombo; Márcia Maria Cândido da Silva

303

Fontes de metionina em rações formuladas com base em aminoácidos totais ou digestíveis para frangas de reposição leves e semipesadas  

Microsoft Academic Search

RESUMO - Foram conduzidos dois experimentos com o objetivo de avaliar a utilização de duas fontes de metionina (em pó ou líquida) em rações formuladas com base em aminoácidos digestíveis ou totais para frangas de reposição leves e semipesadas, nas fases inicial (de 1 a 6 semanas de idade) e de crescimento (de 11 a 16 semanas de idade). Em

Luiz Gustavo Rombola; Douglas Emygdio de Faria; Bruno José Deponti; Flávio Henrique Araujo Silva; Daniel Emygdio de Faria Filho; Otto Mack Junqueira

2008-01-01

304

Four novel sequences in Drosophila melanogaster homologous to the auxiliary Para sodium channel subunit TipE.  

PubMed

TipE is an auxiliary subunit of the Drosophila Para sodium channel. Here we describe four sequences, TEH1-4, homologous to TipE in the Drosophila melanogaster genome, harboring all typical structures of both TipE and the beta-Subunit family of big-conductance Ca(2+)-activated potassium channels: short cytosolic N- and C-terminal stretches, two transmembrane domains, and a large extracellular loop with two disulfide bonds. Whereas TEH1 and TEH2 lack the TipE-specific extension in the extracellular loop, both TEH3 and TEH4 possess two extracellular EGF-like domains. A CNS-specific expression was found for TEH1, while TEH2-4 were more widely expressed. The genes for TEH2-4 are localized close to the tipE gene on chromosome 3L. Coexpression of TEH subunits with Para in Xenopus oocytes showed a strong (30-fold, TEH1), medium (5- to 10-fold, TEH2 and TEH3), or no (TEH4) increase in sodium current amplitude, while TipE increased the current 20-fold. In addition, steady-state inactivation and the recovery from fast inactivation were altered by coexpression of Para with TEH1. We conclude that members of the TEH-family are auxiliary subunits for Para sodium channels and possibly other ion channels. PMID:16325765

Derst, Christian; Walther, Christian; Veh, Rüdiger W; Wicher, Dieter; Heinemann, Stefan H

2006-01-20

305

Uncoupling of Nucleotide Hydrolysis and Polymerization in the ParA Protein Superfamily Disrupts DNA Segregation Dynamics*  

PubMed Central

DNA segregation in bacteria is mediated most frequently by proteins of the ParA superfamily that transport DNA molecules attached via the segrosome nucleoprotein complex. Segregation is governed by a cycle of ATP-induced polymerization and subsequent depolymerization of the ParA factor. Here, we establish that hyperactive ATPase variants of the ParA homolog ParF display altered segrosome dynamics that block accurate DNA segregation. An arginine finger-like motif in the ParG centromere-binding factor augments ParF ATPase activity but is ineffective in stimulating nucleotide hydrolysis by the hyperactive proteins. Moreover, whereas polymerization of wild-type ParF is accelerated by ATP and inhibited by ADP, filamentation of the mutated proteins is blocked indiscriminately by nucleotides. The mutations affect a triplet of conserved residues that are situated neither in canonical nucleotide binding and hydrolysis motifs in the ParF tertiary structure nor at interfaces implicated in ParF polymerization. Instead the residues are involved in shaping the contours of the binding pocket so that nucleotide binding locks the mutant proteins into a configuration that is refractory to polymerization. Thus, the architecture of the pocket not only is crucial for optimal ATPase kinetics but also plays a key role in the polymerization dynamics of ParA proteins that drive DNA segregation ubiquitously in procaryotes.

Dobruk-Serkowska, Aneta; Caccamo, Marisa; Rodriguez-Castaneda, Fernando; Wu, Meiyi; Bryce, Kerstyn; Ng, Irene; Schumacher, Maria A.; Barilla, Daniela; Hayes, Finbarr

2012-01-01

306

EL ANÁLISIS DE CITAS EN TRABAJOS DE INVESTIGADORES COMO MÉTODO PARA EL ESTUDIO DEL USO DE INFORMACIÓN EN BIBLIOTECAS  

Microsoft Academic Search

Resumen: Revisión bibliográfica sobre el análisis de citas como método para el estudio del uso y las necesidades de información por parte de los investigadores como usuarios de bibliotecas. Una vez comparados los estudios locales basados en las publicaciones de los usuarios potenciales de una biblioteca con los estudios de análisis de citas basados en la bibliografía circulante a nivel

Cristóbal Urbano Salido

2001-01-01

307

Theoretical Study of the Mechanism Behind the para-Selective Nitration of Toluene in Zeolite H-Beta  

SciTech Connect

Periodic density functional theory calculations were performed to investigate the origin of the favorable para-selective nitration of toluene exhibited by zeolite H-beta with acetyl nitrate nitration agent. Energy calculations were performed for each of the 32 crystallographically unique Bronsted acid sites of a beta polymorph B zeolite unit cell with multiple Bronsted acid sites of comparable stability. However, one particular aluminum T-site with three favorable Bronsted site oxygens embedded in a straight 12-T channel wall provides multiple favorable proton transfer sites. Transition state searches around this aluminum site were performed to determine the barrier to reaction for both para and ortho nitration of toluene. A three-step process was assumed for the nitration of toluene with two organic intermediates: the pi- and sigma-complexes. The rate limiting step is the proton transfer from the sigma-complex to a zeolite Bronsted site. The barrier for this step in ortho nitration is shown to be nearly 2.5 times that in para nitration. This discrepancy appears to be due to steric constraints imposed by the curvature of the large 12-T pore channels of beta and the toluene methyl group in the ortho approach that are not present in the para approach.

Andersen, Amity; Govind, Niranjan; Subramanian, Lalitha

2011-11-28

308

Evaluación del ciclo de vida aplicada en agrocadenas productivas: un instrumento de gestión ambiental para el diseño de políticas  

Microsoft Academic Search

La Evaluación del Ciclo de Vida del Producto (ECV) ha sido sugerida como un instrumento adecuado para ampliar el análisis y formulación de estrategias y políticas al utilizar el enfoque de Cadenas Globales de Mercancías. En este artículo se analizan los alcances de la aplicación de la ECV en diferentes sistemas de gestión ambiental lo cual permite establecer las áreas

Rafael Díaz Porras; Marjorie Hartley Ballestero

2006-01-01

309

Gestión para el desarrollo local sostenible en Granjas Agroindustriales y Empresas Azucareras del MINAZ de la provincia de Cienfuegos  

Microsoft Academic Search

La investigación se realizó en las entidades del MINAZ, teniendo como título: “Gestión para el desarrollo local sostenible en Granjas Agroindustriales y Empresas Azucareras del MINAZ en la provincia de Cienfuegos”. Tiene como objetivo general proponer un sistema de gestión ambiental integral que permita valorar e implantar las políticas de desarrollo local sostenible de las granjas agroindustriales y empresas azucareras

Eduardo Julio López Bastida; Mileisy Balbis Morejón

2008-01-01

310

Filtros hidráulicos PureForce TM diseñados para satisfacer o exceder los requisitos de alto rendimiento del equipo actual  

Microsoft Academic Search

El filtro hidráulico que antes no existía en los sistemas hidráulicos, ahora se ha transformado en un componente crítico. De hecho, son muy pocas las áreas de filtración que han cambiado con tanta rapidez como la hidráulica. La razón de un cambio tan rápido es que los sistemas hidráulicos están reemplazando a otros tipos de transmisiones. Para mejorar la seguridad

Medio Oriente; América del Sur

2009-01-01

311

APROXIMACION A LA ENSEÑANZA PARA PIANO A TRAVÉS DE LA CÁTEDRA DE PEDRO ALBÉNIZ EN EL REAL CONSERVATORIO DE MADRID  

Microsoft Academic Search

Pedro Albéniz como primer catedrático del Real Conservatorio de Madrid impulsó la consolidación del piano romántico durante la primera mitad del s. XIX, normalizando su enseñanza e introduciendo la escuela moderna del piano español, basada en el pianismo francés de la primera mitad del s. XIX. En su Método Completo para piano recogió las bases de su escuela pianística y

Gemma Salas

1999-01-01

312

A FALTA DE OPORTUNIDADES DE INSERÇÃO PARA OS CAIÇARAS E SEUS DESCENDENTES NA ATIVIDADE TURÍSTICA: O CASO DE ILHABELA  

Microsoft Academic Search

Introdução O turismo tem crescido em ritmo intenso em todo o Brasil. No litoral norte de São Paulo, em virtude, principalmente, da proximidade com a capital do estado - maior fluxo emissivo de turistas - esse crescimento é bastante acentuado. Ilhabela detém belezas naturais e cenários geográficos que estimulam os turistas e veranistas a escolherem esse destino para suas férias

Claudia Maria Astorino

313

Esquema de redundancia y distribución de carga de alta disponibilidad para la prestación de telefonía IP usando SIP  

Microsoft Academic Search

En este artículo se presenta un esquema de distribu ción de carga y redundancia en la infraestructura de un ISP (Intern et Service Provider) para la prestación de servicios de telefo nía IP (ITSPs) sobre Internet usando el protocolo SIP (Session Ini tiation Protocol) garantizando niveles de acceso al servici o similares a la PSTN (Public Switched Telephone Network) y

Andrés Parra Londoño; Fabio G. Guerrero

2009-01-01

314

Conservation of ParaHox genes' function in patterning of the digestive tract of the marine gastropod Gibbula varia  

PubMed Central

Background Presence of all three ParaHox genes has been described in deuterostomes and lophotrochozoans, but to date one of these three genes, Xlox has not been reported from any ecdysozoan taxa and both Xlox and Gsx are absent in nematodes. There is evidence that the ParaHox genes were ancestrally a single chromosomal cluster. Colinear expression of the ParaHox genes in anterior, middle, and posterior tissues of several species studied so far suggest that these genes may be responsible for axial patterning of the digestive tract. So far, there are no data on expression of these genes in molluscs. Results We isolated the complete coding sequences of the three Gibbula varia ParaHox genes, and then tested their expression in larval and postlarval development. In Gibbula varia, the ParaHox genes participate in patterning of the digestive tract and are expressed in some cells of the neuroectoderm. The expression of these genes coincides with the gradual formation of the gut in the larva. Gva-Gsx patterns potential neural precursors of cerebral ganglia as well as of the apical sensory organ. During larval development this gene is involved in the formation of the mouth and during postlarval development it is expressed in the precursor cells involved in secretion of the radula, the odontoblasts. Gva-Xolx and Gva-Cdx are involved in gut patterning in the middle and posterior parts of digestive tract, respectively. Both genes are expressed in some ventral neuroectodermal cells; however the expression of Gva-Cdx fades in later larval stages while the expression of Gva-Xolx in these cells persists. Conclusions In Gibbula varia the ParaHox genes are expressed during anterior-posterior patterning of the digestive system. This colinearity is not easy to spot during early larval stages because the differentiated endothelial cells within the yolk permanently migrate to their destinations in the gut. After torsion, Gsx patterns the mouth and foregut, Xlox the midgut gland or digestive gland, and Cdx the hindgut. ParaHox genes of Gibbula are also expressed during specification of cerebral and ventral neuroectodermal cells. Our results provide additional support for the ancestral complexity of Gsx expression and its ancestral role in mouth patterning in protostomes, which was secondarily lost or simplified in some species.

2010-01-01

315

A remarkably stable TipE gene cluster: evolution of insect Para sodium channel auxiliary subunits  

PubMed Central

Background First identified in fruit flies with temperature-sensitive paralysis phenotypes, the Drosophila melanogaster TipE locus encodes four voltage-gated sodium (NaV) channel auxiliary subunits. This cluster of TipE-like genes on chromosome 3L, and a fifth family member on chromosome 3R, are important for the optional expression and functionality of the Para NaV channel but appear quite distinct from auxiliary subunits in vertebrates. Here, we exploited available arthropod genomic resources to trace the origin of TipE-like genes by mapping their evolutionary histories and examining their genomic architectures. Results We identified a remarkably conserved synteny block of TipE-like orthologues with well-maintained local gene arrangements from 21 insect species. Homologues in the water flea, Daphnia pulex, suggest an ancestral pancrustacean repertoire of four TipE-like genes; a subsequent gene duplication may have generated functional redundancy allowing gene losses in the silk moth and mosquitoes. Intronic nesting of the insect TipE gene cluster probably occurred following the divergence from crustaceans, but in the flour beetle and silk moth genomes the clusters apparently escaped from nesting. Across Pancrustacea, TipE gene family members have experienced intronic nesting, escape from nesting, retrotransposition, translocation, and gene loss events while generally maintaining their local gene neighbourhoods. D. melanogaster TipE-like genes exhibit coordinated spatial and temporal regulation of expression distinct from their host gene but well-correlated with their regulatory target, the Para NaV channel, suggesting that functional constraints may preserve the TipE gene cluster. We identified homology between TipE-like NaV channel regulators and vertebrate Slo-beta auxiliary subunits of big-conductance calcium-activated potassium (BKCa) channels, which suggests that ion channel regulatory partners have evolved distinct lineage-specific characteristics. Conclusions TipE-like genes form a remarkably conserved genomic cluster across all examined insect genomes. This study reveals likely structural and functional constraints on the genomic evolution of insect TipE gene family members maintained in synteny over hundreds of millions of years of evolution. The likely common origin of these NaV channel regulators with BKCa auxiliary subunits highlights the evolutionary plasticity of ion channel regulatory mechanisms.

2011-01-01

316

Intensity-Modulated Radiation Therapy for the Treatment of Squamous Cell Anal Cancer With Para-aortic Nodal Involvement  

SciTech Connect

Purpose: To determine the rates of toxicity, locoregional control, distant control, and survival in anal cancer patients with para-aortic nodal involvement, treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy at a single institution. Methods and Materials: Between 2001 and 2007, 6 patients with squamous cell anal cancer and para-aortic nodal involvement were treated with IMRT and concurrent infusional 5-fluorouracil and cisplatin. The primary tumor was treated with a median dose of 57.5 Gy (range, 54-60 Gy), involved para-aortic, pelvic, and inguinal lymph nodes were treated with a median dose of 55 Gy (range, 50.5-55 Gy), and noninvolved nodal regions were treated with a median dose of 45 Gy (range, 43.5-45 Gy). Results: After a median follow-up of 25 months, none of the patients had a recurrence at the primary tumor, pelvic/inguinal nodes, or para-aortic nodes, whereas 2 patients developed distant metastases to the liver. Four of the 6 patients are alive. The 3-year actuarial locoregional control, distant control, and overall survival rates were 100%, 56%, and 63%, respectively. Four of the 6 patients developed Grade 3 acute gastrointestinal toxicity during chemoradiation. Conclusions: Intensity-modulated radiotherapy and concurrent chemotherapy could potentially serve as definitive therapy in anal cancer patients with para-aortic nodal involvement. Adjuvant chemotherapy may be indicated in these patients, as demonstrated by the distant failure rates. These patients need to be followed carefully because of the potential for treatment-related toxicities.

Hodges, Joseph C. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Das, Prajnan, E-mail: PrajDas@mdanderson.or [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Eng, Cathy [Department of Gastrointestinal Medical Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Reish, Andrew G. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Beddar, A. Sam [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Delclos, Marc E.; Krishnan, Sunil; Crane, Christopher H. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

2009-11-01

317

BUDDA (Bulge/Disk Decomposition Analysis) - um novo programa para análise estrutural de galáxias  

NASA Astrophysics Data System (ADS)

Tem sido prática comum nos últimos anos estudar a distribuição de luminosidade em galáxias fazendo uso da informação contida em toda a imagem da galáxia, já que esta técnica tem se mostrado muito mais confiável do que o simples ajuste de perfis radiais de luminosidade. Através destes estudos bidimensionais, melhores resultados tem sido obtidos na análise e.g. do Plano Fundamental, de correlações entre os parâmetros estruturais de galáxias, de sub-estruturas como barras e anéis nucleares etc. Apresentamos um novo código bidimensional, o BUDDA, de análise estrutural de galáxias, que será disponibilizado para a comunidade. Desenvolvido por nós, o código determina os parâmetros estruturais de galáxias de forma prática e robusta, e pode ser aplicado genericamente em qualquer estudo sobre a formação, evolução e estrutura de galáxias. O programa ainda permite a avaliação direta de sub-estruturas, através de imagens residuais que são obtidas ao se subtrair, das imagens originais, bojo e disco sintéticos que melhor representam essas componentes da galáxia sob consideração. Será apresentada a forma de utilização do código, bem como séries de testes que atestam a sua funcionalidade. Além disso, os resultados da aplicação do código em uma amostra de 51 galáxias serão expostos como exemplo prático, e do seu enorme potencial de uso.

Gadotti, D. A.; de Souza, R. E.; Dos Anjos, S.

2003-08-01

318

Why are para-hydrogen clusters superfluid? A quantum theorem of corresponding states study.  

PubMed

The quantum theorem of corresponding states is applied to N=13 and N=26 cold quantum fluid clusters to establish where para-hydrogen clusters lie in relation to more and less quantum delocalized systems. Path integral Monte Carlo calculations of the energies, densities, radial and pair distributions, and superfluid fractions are reported at T=0.5 K for a Lennard-Jones (LJ) (12,6) potential using six different de Boer parameters including the accepted value for hydrogen. The results indicate that the hydrogen clusters are on the borderline to being a nonsuperfluid solid but that the molecules are sufficiently delocalized to be superfluid. A general phase diagram for the total and kinetic energies of LJ (12,6) clusters encompassing all sizes from N=2 to N=infinity and for the entire range of de Boer parameters is presented. Finally the limiting de Boer parameters for quantum delocalization induced unbinding ("quantum unbinding") are estimated and the new results are found to agree with previous calculations for the bulk and smaller clusters. PMID:20707573

Sevryuk, Mikhail B; Toennies, J Peter; Ceperley, David M

2010-08-14

319

Cobalt-Schiff base complex catalyzed oxidation of para-substituted phenolics. Preparation of benzoquinones  

SciTech Connect

Para-substituted phenolics, serving as models for lignin (a renewable source of carbon), are oxidized to the corresponding benzoquinone with oxygen in the presence of catalytic amounts of Co-Schiff base complexes. The reaction products observed depend on the structure of the catalyst. The 5-coordinate catalysts (pyridine)[bis(salicylidene)ethylenediamine]cobalt[(pyr)Co(salen)]and[bis(salicylideneamino)ethylamine]cobalt [Co(n-Me salpr)] convert syringyl alcohol (3,5-dimethoxy-4-hydroxybenzyl alcohol) to 2,6-dimethoxybenzoquinone in high yield. In contrast, syringaldehyde (3,5-dimethoxy-4-hydroxybenzaldehyde) is unreactive toward these catalysts. However, the 4-coordinate Co(salen) converts syringaldehyde to 2,6-dimethoxybenzoiquinone in 72% isolated yield. Phenols bearing a single methoxy group on the ring are unreactive toward any catalyst in MeOH. However, vanillyl alcohol (3-methoxy-4-hydroxybenzyl alcohol) is converted to 2-methoxybenzo-quinone with Co(N-Me salpr) and oxygen in 43% yield in CH{sub 2}Cl{sub 2} and 58% yield in CH{sub 2}Cl{sub 2} in the presence of 1% CuCl{sub 2}. The success of the oxidations appears to be related to the ease of removal of the phenolic hydrogen by the Co/O{sub 2} complex. Competitive deactivation of the catalyst occurs with substrates of lower reactivity. 84 tabs.

Bozell, J.J.; Hames, B.R. [National Renewable Energy Lab., Golden, CO (United States); Dimmel, D.R. [Institute of Paper Science and Technology, Atlanta, GA (United States)

1995-04-21

320

Serotypes associated with the development of pneumococcal para-pneumonic effusion in adults.  

PubMed

Serotypes 1, 3, 7F and 19A are implicated in childhood pneumococcal para-pneumonic effusion (PPE). It is not known whether the same is true for adult PPE. A prospective cohort study was conducted over a 2-year period. Consecutive adults admitted with community-acquired pneumonia (CAP) were studied. Pneumococcal serotype was identified from urine samples using a multiplex immunoassay. Of 920 patients recruited, 366 had pneumococcal CAP; 100 of these had PPE and a serotype was determined in 73 patients. Factors associated with PPE were age, pneumonia severity index score and serotype. Serotypes most associated with PPE were 1 (18 (45%) out of 40), 19A (9 (45%) out of 20) and 3 (8 (40%) out of 20). Serotypes common in childhood PPE were independently associated with adult PPE (adjusted OR 2.3; p = 0.003). Serotypes not included in the 7-valent pneumococcal conjugate vaccine (PCV) were more likely to be associated with PPE (OR 2.1; p = 0.024) compared with those in the vaccine. Serotypes included in PCV-13 were as likely to be associated with PPE as those that are not (OR 0.8; p = 0.301). Serotypes 1, 3, 7F and 19A are independently associated with adult PPE, a similar finding to childhood PPE. Serotype replacement following pneumococcal vaccine implementation may influence the spectrum of clinical disease. PMID:23258784

Bewick, Thomas; Sheppard, Carmen; Greenwood, Sonia; Slack, Mary; Trotter, Caroline; George, Robert; Lim, Wei Shen

2013-09-01

321

Taxas de eventos para as fontes astrofísicas do detector Mario Schenberg  

NASA Astrophysics Data System (ADS)

O detector de ondas gravitacionais Mario Schenberg será sensível a sinais que cheguem à Terra com amplitude h~10-21 e dentro da faixa em frequências que varia de 3,0 a 3,4 kHz. As principais fontes astrofísicas em condições de gerar um sinal detectável pela antena Schenberg são: colapsos estelares que produzam eventos do tipo supernova; instabilidades hidrodinâmicas em estrelas de nêutrons; excitação dos modos fluído (modos f) de estrelas de nêutrons; excitação dos primeiros modos quadrupolares de buracos negros com massa ~ 3,8 M¤; coalescências de estrelas de nêutrons e buracos negros em sistemas binários e, ainda, espiralações de mini-buracos negros. Neste trabalho nós determinamos as taxas de eventos para o Schenberg associadas a dois tipos de fontes: através da de-excitação dos modos f de estrelas de nêutrons e através da coalescência de mini-buracos negros de 0,5 M¤ (que atualmente têm sido colocados como possíveis candidatos a objetos massivos do halo Galáctico). Nós mostramos que esses tipos de fontes poderão produzir sinais em ondas gravitacionais com uma taxa em torno de um evento por ano dentro da banda do Schenberg.

Castro, C. S.; Araujo, J. C. N.; Miranda, O. D.; Aguiar, O. D.

2003-08-01

322

Porous poly(para-phenylene) scaffolds for load-bearing orthopedic applications.  

PubMed

The focus of this study was to fabricate and investigate the mechanical behavior of porous poly(para-phenylene) (PPP) for potential use as a load-bearing orthopedic biomaterial. PPPs are known to have exceptional mechanical properties due to their aromatic backbone; however, the manufacturing and properties of PPP porous structures have not been previously investigated. Tailored porous structures with either small (150-250µm) or large (420-500µm) pore sizes were manufactured using a powder-sintering/salt-leaching technique. Porosities were systematically varied using 50 to 90vol%. Micro-computed tomography (µCT) and scanning electron microscopy (SEM) were used to verify an open-cell structure and investigate pore morphology of the scaffolds. Uniaxial mechanical behavior of solid and porous PPP samples was characterized through tensile and compressive testing. Both modulus and strength decreased with increasing porosity and matched well with foam theory. Porous scaffolds showed a significant decrease in strain-to-failure (<4%) under tensile loading and experienced linear elasticity, plastic deformation, and densification under compressive loading. Over the size ranges tested, pore size did not significantly influence the mechanical behavior of the scaffolds on a consistent basis. These results are discussed in regards to use of porous PPP for orthopedic applications and a prototype porous interbody fusion cage is presented. PMID:24374261

DiRienzo, Amy L; Yakacki, Christopher M; Frensemeier, Mareike; Schneider, Andreas S; Safranski, David L; Hoyt, Anthony J; Frick, Carl P

2014-02-01

323

Creation and evolution of net proton hyperpolarization arising from para-hydrogenation.  

PubMed

When a hydrogenation reaction is carried out with gaseous hydrogen enriched in its para- isomer in the earth magnetic field (prior to adiabatic insertion of the sample in the NMR magnet), enhanced proton longitudinal order (represented by 2I(z)(A)I(z)(B)) is created but also difference of enhanced polarizations (I(z)(A)-I(z)(B)). In a first part, it is shown theoretically and experimentally that the longitudinal relaxation time of this polarization difference is roughly twice the ones of individual polarizations. The second part is devoted to a pulse sequence designed for transforming this difference into net hyperpolarization. The evolution of this global hyperpolarization is studied experimentally in a third part and it is observed that a fraction of hyperpolarization possesses an effective longitudinal relaxation time similar to the one of the initial polarization difference. Those experimental results are interpreted by numerical calculations based on Solomon-type equations including the longitudinal order and possibly dipolar-csa cross correlation rates. PMID:21402486

Reineri, Francesca; Bouguet-Bonnet, Sabine; Canet, Daniel

2011-05-01

324

Tensile behavior of porous scaffolds made from poly(para phenylene) - biomed 2013.  

PubMed

The goal of this study was to fabricate and mechanically characterize a high-strength porous polymer scaffold for potential use as an orthopedic device. Poly(para-phenylene) (PPP) is an excellent candidate due to its exceptional strength and stiffness and relative inertness, but has never been explicitly investigated for use as a biomedical device. PPP has strength values 3 to 10 times higher and an elastic modulus nearly an order of magnitude higher than traditional polymers such as poly(methyl methacrylate) (PMMA), polycaprolactone (PCL), ultra-high molecular weight polyethylene (UHMWPE), and polyurethane (PU) and is significantly stronger and stiffer than polyetheretherketone (PEEK). By utilizing PPP we can overcome the mechanical limitations of traditional porous polymeric scaffolds since the outstanding stiffness of PPP allows for a highly porous structure appropriate for osteointegration that can match the stiffness of bone (100-250 MPa), while maintaining suitable mechanical properties for soft-tissue fixation. Porous samples were manufactured by powder sintering followed by particle leaching. The pore volume fraction was systematically varied from 50?80 vol% for a pore sizes from150-500 µm, as indicated by previous studies for optimal osteointegration. The tensile modulus of the porous samples was compared to the rule of mixtures, and closely matches foam theory up to 70 vol%. The experimental modulus for 70 vol% porous samples matches the stiffness of bone and contains pore sizes optimal for osteointegration. PMID:23686195

Dirienzo, Amy L; Yakacki, Christopher M; Safranski, David L; Frick, Carl P

2013-01-01

325

ParaText : scalable solutions for processing and searching very large document collections : final LDRD report.  

SciTech Connect

This report is a summary of the accomplishments of the 'Scalable Solutions for Processing and Searching Very Large Document Collections' LDRD, which ran from FY08 through FY10. Our goal was to investigate scalable text analysis; specifically, methods for information retrieval and visualization that could scale to extremely large document collections. Towards that end, we designed, implemented, and demonstrated a scalable framework for text analysis - ParaText - as a major project deliverable. Further, we demonstrated the benefits of using visual analysis in text analysis algorithm development, improved performance of heterogeneous ensemble models in data classification problems, and the advantages of information theoretic methods in user analysis and interpretation in cross language information retrieval. The project involved 5 members of the technical staff and 3 summer interns (including one who worked two summers). It resulted in a total of 14 publications, 3 new software libraries (2 open source and 1 internal to Sandia), several new end-user software applications, and over 20 presentations. Several follow-on projects have already begun or will start in FY11, with additional projects currently in proposal.

Crossno, Patricia Joyce; Dunlavy, Daniel M.; Stanton, Eric T.; Shead, Timothy M.

2010-09-01

326

Interface Properties of Organic para-Hexaphenyl/?-Sexithiophene Heterostructures Deposited on Highly Oriented Pyrolytic Graphite  

PubMed Central

It was recently reported, that heterostructures of para-hexaphenyl (p-6P) and ?-sexithiophene (6T) deposited on muscovite mica exhibit the intriguing possibility to prepare lasing nanofibers of tunable emission wavelength. For p-6P/6T heterostructures, two different types of 6T emission have been observed, namely, the well-known red emission of bulk 6T crystals and additionally a green emission connected to the interface between p-6P and 6T. In this study, the origin of the green fluorescence is investigated by photoelectron spectroscopy (PES). As a prerequisite, it is necessary to prepare structurally similar organic crystals on a conductive surface, which leads to the choice of highly oriented pyrolytic graphite (HOPG) as a substrate. The similarity between p-6P/6T heterostructures on muscovite mica and on HOPG is evidenced by X-ray diffraction (XRD), scanning force microscopy (SFM), and optical spectroscopy. PES measurements show that the interface between p-6P and 6T crystals is sharp on a molecular level without any sign of interface dipole formation or chemical interaction between the molecules. We therefore conclude that the different emission colors of the two 6T phases are caused by different types of molecular aggregation.

2013-01-01

327

Optimal timing algorithms of para-aortic counterpulsation device: an animal study.  

PubMed

Para-aortic counterpulsation device (PACD) is a promising therapy for severe heart failure (HF). However, the lack of knowledge about mechanisms has limited its clinical application. The aim of this study was to investigate the optimal timing algorithms. At the following four triggering algorithms, pre-R-wave-deflation and dicrotic notch-inflation (PD), pre-R-wave-deflation and postdicrotic notch-inflation (PP), R-wave-deflation and dicrotic notch-inflation (RD), and R-wave-deflation and postdicrotic notch-inflation (RP), hemodynamic effects of PACD were assessed in vivo. There was more significant promotion of left mean coronary artery flow (Q(LM)), carotid artery flow (Q(CA)), cardiac output (CO), pulmonary artery flow/LA pressure ratio (Q(PA)/LAP), left ventricular myocardial oxygen consumption (LVVO(2)), external LV work (ELVW), and cardiac mechanical efficiency (CME) at RD and RP models than PD and PP models. R-wave-deflation and postdicrotic notch-inflation model provided further benefits. There was significant correlation between LV functional parameters and carotid arterial reflux, but aortic pressure-related parameters. Filling at beginning of LV systolic phase and ejection at the end of isovolumic relaxation phase were the optimal triggering algorithms of PACD. It is suggested that carotid artery reflows and ventricular pressure-related parameters should be used as reference standard to adjust the timing of balloon inflation or deflation. PMID:22236623

Zhang, Guang-Wei; Wen, Ti; Gu, Tian-Xiang; Yu, Yang; Zhao, Ye; Zhang, Yu-Hai; Wang, Chun

2012-01-01

328

Electronic effects of para-substitution on the melting points of TAAILs.  

PubMed

Owing to numerous new applications, the interest in "task-specific" ionic liquids increased significantly over the last decade. But, unfortunately, the imidazolium-based ionic liquids (by far the most frequently used cations) have serious limitations when it comes to modifications of their properties. The new generation of ionic liquids, called tunable aryl-alkyl ionic liquids (TAAILs), replaces one of the two alkyl chains on the imidazolium ring with an aryl ring which allows a large degree of functionalization. Inductive, mesomeric, and steric effects as well as potentially also ?-? and ?-?(+) interactions provide a wide range of possibilities to tune this new class of ILs. We investigated the influence of electron-withdrawing and -donating substituents at the para-position of the aryl ring (NO(2), Cl, Br, EtO(CO), H, Me, OEt, OMe) by studying the changes in the melting points of the corresponding bromide and bis(trifluoromethanesulfonyl)imide, (N(Tf)(2)(-)), salts. In addition, we calculated (B3LYP/6-311++G(d,p)) the different charge distributions of substituted 1-aryl-3-propyl-imidazolium cations to understand the experimentally observed effects. The results indicated that the presence of electron-donating and -withdrawing groups leads to strong polarization effects in the cations. PMID:21254445

Schulz, Tobias; Ahrens, Sebastian; Meyer, Dirk; Allolio, Christoph; Peritz, Anke; Strassner, Thomas

2011-03-01

329

Polychlorinated Dibenzo-para-dioxins and Polychlorinated Dibenzofurans in Sediments from U.K. Estuaries  

NASA Astrophysics Data System (ADS)

Concentrations of polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been determined in sediments from U.K. coastal locations adjacent to the estuaries of the Dee, Humber, Mersey, Tees, Tweed and Tyne and from an offshore site in Morecambe Bay. The sediments had total PCDD/DF concentrations of <100 pg g -1, except for the Dee and Morecambe Bay which had total PCDD (total PCDF) concentrations of 750 (390) and 207 pg g -1 (116 pg g -1), respectively. However, estuarine sediments collected during axial transects of Dee, Humber and Clyde Estuaries had total PCDD (total PCDF) concentrations in the range 530-1880 (340-710), 300-1890 (260-1240) and 290-4670 pg g -1 (100-1540 pg g -1), respectively. Examination of the homologue groups showed that about 70% of PCDDs were in the octa-chlorinated form in the Dee and Clyde, whereas for PCDFs the hepta- and hexa-chlorinated forms were relatively more important. The association of PCDD/DFs with particle surfaces was interpreted using data on sediment characteristics and a two-stage adsorption model. The conclusions from this study have implications for the estuarine transport of PCDD and PCDF and their uptake by benthic organisms.

Tyler, A. O.; Millward, G. E.; Jones, P. H.; Turner, A.

1994-07-01

330

Synthesis and spectral studies of platinum complexes of para-substituted 4-phenylthiosemicarbazides  

NASA Astrophysics Data System (ADS)

Platinum(II) complexes of para-substituted 4-phenylthiosemicarbazides, RPhNHCSNHNH 2 (R = H, CH 3, Br, F and NO 2) have been prepared and characterised by infrared and multinuclear NMR spectroscopy. The thiosemicarbazides act as bidentate ligands bonding through the sulphur and hydrazinic nitrogen atoms to form mixtures of cis- and trans-isomers of square planar complexes. 1H and 195Pt NMR spectroscopy suggest that the trans-isomer predominates in solution and that the relative ratio of trans: cis increases with increasing temperature of synthesis. 15N NMR spectroscopy has also been used to assign the cis- and trans-isomers of platinum complexes of 15N enriched 4-(4'-bromophenyl)thiosemicarbazide using 15N chemical shifts and … 1J 195Pt? 15N… values. The magnitude of the coupling constant … 1J 195Pt? 15N… of 238 Hz compares favourably with other platinum(II) complexes in which the 15N donor atom is trans to 15N and thus confirms the assignment of the trans-isomer as the predominant one in solution.

Arendse, Malcolm J.; Green, Ivan R.; Koch, K. R.

1997-09-01

331

Searching for auxetics with DYNA3D and ParaDyn  

NASA Astrophysics Data System (ADS)

The present special issue of physica status solidi (b), guest-edited by Krzysztof W. Wojciechowski, Andrew Alderson, Arkadiusz Braka, and Kim L. Alderson, is dedicated to Auxetics and Related Systems - materials which exhibit negative Poisson's ratio behaviour. Most papers were presented at a workshop which was held in Pozna-Bdlewo, 27-30 June 2004.In our Editor's Choice [1] novel simulations with a parallel finite element program, ParaDyn, have been conducted to study the formation of auxetic materials. Structures composed of either brick elements (hexahedra) or shell elements are constructed in a regular array of panels. These structures are compressed and relaxed to form an initial state for an auxetic (foam-like) material. The foam structure shown is composed of 208896 shell elements arranged in four by four panels. Applying a uniaxial compression to this structure characterizes the material behaviour of the lateral surfaces as normal (expanding) or auxetic (compressing).The first author, William G. Hoover, has been working in areas such as statistical and applied mechanics, nonlinear and molecular dynamics and is now pursuing, as he states on his own webpage, an active retired research career as Professor Emeritus of UC Davis.

Hoover, Wm. G.; Hoover, C. G.

2005-03-01

332

Analysis of passive motion of para- and retropharyngeal structures during swallowing using dynamic magnetic resonance imaging.  

PubMed

The purpose of this study was to analyze passive motion of the para- and retropharyngeal space (PRS) during swallowing using dynamic magnetic resonance imaging (MRI). We conducted a preliminary study involving 30 healthy volunteers who underwent dynamic MRI. Consecutive MRI axial images were obtained by examining the plane parallel to the hard palate at the level of the anterior inferior corner of C2. Anterior displacement of the posterior pharyngeal wall (PPW) was measured as a motion index of pharyngeal contraction. The displacement and internal angle of the bilateral external and internal carotid arteries (ECA and ICA) and the bilateral centroids of the PRS area, as well as the increase in PRS area, were calculated at rest and at maximum pharyngeal contraction. In most participants, the bilateral ECA, ICA, and centroids were anterointernally displaced by pharyngeal contraction. The normalized ECA displacement (r = 0.64, r (2) = 0.41), normalized ICA displacement (r = 0.60, r (2) = 0.37), and normalized centroid displacement (r = 0.43, r (2) = 0.19) were more than moderately positively correlated with the normalized PPW displacement. The normalized PRS area increase (r = 0.35, r (2) = 0.12) was weakly positively correlated with the normalized PPW displacement. These results revealed that PRS area increased as the ECA and ICA were drawn anterointernally via its passive motion by pharyngeal contraction. PMID:24859486

Chitose, Shun-Ichi; Haraguchi, Masahiro; Nagata, Shuji; Katayama, Reiji; Sato, Kiminori; Fukahori, Mioko; Sueyoshi, Shintaro; Kurita, Takashi; Abe, Toshi; Nakashima, Tadashi

2014-06-01

333

[Classification as carcinogenic for 2,3,7,8-tetrachlorodibenzo-para-dioxin: an eventful journey].  

PubMed

Carcinogenicity of 2,3,7,8-tetrachlorodibenzo-para-dioxin (2,3,7,8-TCDD) and some other dioxin congeners is long time discussed by epidemiological and experimental studies, often with conflicting findings. The inclusion of 2,3,7,8-TCDD in Group 1 by 1ARC in 1997 was based essentially on mechanistic evidence and experimental studies despite the limited evidence in humans. This procedure generated a lot of controversy. Some scientists agree with this classification and sometimes suggested increased cancer mortality risk with TCDD daily intake similar to those of the general population. Other authors re-analyzing data mainly from caselist previously investigated did not confirm the 2,3,7,8-TCDD carcinogenicity. In the review process of carcinogenic substances by IARC in 2010, the evidence for 2,3,7,8-TCDD carcinogenicity in humans upgraded from limited to sufficient, due to confirmed and integrated epidemiological evidences. It is also confirmed that these findings relate to all cancers combined, while for some "classic" cancers related to TCDD (as soft tissue sarcoma and non-Hodgkin lymphoma) the evidence remains limited. In this paper a literature review accompanied by comments is reported with the aim to provide information about the evaluation process and tools for its more critical and scrupulous interpretation. PMID:21425634

Apostoli, Pietro; Bergonzi, Roberto; Catalani, Simona

2011-01-01

334

Para-veterinary professionals and the development of quality, self-sustaining community-based services.  

PubMed

Livestock are a major asset for rural households throughout the developing world and are increasingly regarded as a means of reducing poverty. However, many rural areas are characterised by limited or no accessibility to veterinary services. Economic theory indicates that primary level services can be provided by para-veterinary professionals working as private operators and as an outreach component of veterinary clinics and pharmacies in small urban centres. Experience from the development of community-based animal health worker (CAHW) systems indicates that these workers can have a substantial impact on livestock morbidity and mortality through the treatment or prevention of a limited range of animal health problems. Factors for success include community involvement in the design and implementation of these systems, and involvement of the private sector to supply and supervise CAHWs. Examples of privatised and veterinary supervised CAHW networks are cited to show the considerable potential of this simple model to improve primary animal health services in marginalised areas. An analysis of constraints indicates that inappropriate policies and legislation are a major concern. By referring to the section on the evaluation of Veterinary Services in the OIE (World organisation for animal health) Terrestrial Animal Health Code, the paper proposes guidelines to assist governments in improving the regulation, quality, and co-ordination of privatised, veterinary supervised CAHW systems. PMID:15200100

Catley, A; Leyland, T; Mariner, J C; Akabwai, D M O; Admassu, B; Asfaw, W; Bekele, G; Hassan, H Sh

2004-04-01

335

LabVIEW-based control software for para-hydrogen induced polarization instrumentation.  

PubMed

The elucidation of cell metabolic mechanisms is the modern underpinning of the diagnosis, treatment, and in some cases the prevention of disease. Para-Hydrogen induced polarization (PHIP) enhances magnetic resonance imaging (MRI) signals over 10 000 fold, allowing for the MRI of cell metabolic mechanisms. This signal enhancement is the result of hyperpolarizing endogenous substances used as contrast agents during imaging. PHIP instrumentation hyperpolarizes Carbon-13 ((13)C) based substances using a process requiring control of a number of factors: chemical reaction timing, gas flow, monitoring of a static magnetic field (Bo), radio frequency (RF) irradiation timing, reaction temperature, and gas pressures. Current PHIP instruments manually control the hyperpolarization process resulting in the lack of the precise control of factors listed above, resulting in non-reproducible results. We discuss the design and implementation of a LabVIEW based computer program that automatically and precisely controls the delivery and manipulation of gases and samples, monitoring gas pressures, environmental temperature, and RF sample irradiation. We show that the automated control over the hyperpolarization process results in the hyperpolarization of hydroxyethylpropionate. The implementation of this software provides the fast prototyping of PHIP instrumentation for the evaluation of a myriad of (13)C based endogenous contrast agents used in molecular imaging. PMID:24784636

Agraz, Jose; Grunfeld, Alexander; Li, Debiao; Cunningham, Karl; Willey, Cindy; Pozos, Robert; Wagner, Shawn

2014-04-01

336

HERRAMIENTAS GERENCIALES PARA EL POSICIONAMIENTO DE LA EMPRESA SOSTENIBLE Y EL MARKETING ECOLÓGICO Management tools and positioning of sustainable enterprises and marketing ecological  

Microsoft Academic Search

RESUMEN La civilización humana está direccionando su acción comercial hacia el componente ecológico, tomando como principio la gerencia para proyectarse al mercado verde es decir, productos que generen menor impacto ambiental. La presente investigación tuvo como objetivo determinar las herramientas gerenciales para el posicionamiento de la empresa sostenible y el marketing ecológico. Este trabajo de investigación fue descriptivo, transeccional y

Dalia Plata de Plata

337

DISEÑO Y CONSTRUCCIÓN DE UN PROTOTIPO DIGITAL PARA DIAGNÓSTICAR FALLAS EN MOTORES DE INDUCCIÓN DESIGN AND CONSTRUCTION OF A DIGITAL PROTOTYPE TO DIAGNOSE FAULTS IN INDUCTION MOTORS  

Microsoft Academic Search

Recibido para revisar octubre 06 de 2006, aceptado febrero 05 de 2007, versión final febrero 28 de 2007 RESUMEN: En este trabajo se presenta el desarrollo de un prototipo digital utilizando un procesador de señales digitales DSP, al cual se le han incorporado dos algoritmos para diagnosticar fallas en el estator de motores de inducción. El primer algoritmo utiliza las

FERNANDO VILLADA DUQUE; Ingeniero Electricista; VELÁSQUEZ V; Ingeniero Electrónico; DIEGO R. CADAVID

2007-01-01

338

Involvement of the azorhizobial chromosome partition gene (parA) in the onset of bacteroid differentiation during Sesbania rostrata stem nodule development.  

PubMed

A parA gene in-frame deletion mutant of Azorhizobium caulinodans ORS571 (ORS571-?parA) was constructed to evaluate the roles of the chromosome-partitioning gene on various bacterial traits and on the development of stem-positioned nodules. The ?parA mutant showed a pleiomorphic cell shape phenotype and was polyploid, with differences in nucleoid sizes due to dramatic defects in chromosome partitioning. Upon inoculation of the ?parA mutant onto the stem of Sesbania rostrata, three types of immature nodule-like structures with impaired nitrogen-fixing activity were generated. Most showed signs of bacteroid early senescence. Moreover, the ?parA cells within the nodule-like structures exhibited multiple developmental-stage phenotypes. Since the bacA gene has been considered an indicator for bacteroid formation, we applied the expression pattern of bacA as a nodule maturity index in this study. Our data indicate that the bacA gene expression is parA dependent in symbiosis. The presence of the parA gene transcript was inversely correlated with the maturity of nodule; the transcript was switched off in fully mature bacteroids. In summary, our experimental evidence demonstrates that the parA gene not only plays crucial roles in cellular development when the microbe is free-living but also negatively regulates bacteroid formation in S. rostrata stem nodules. PMID:21571889

Liu, Chi-Te; Lee, Kyung-Bum; Wang, Yu-Sheng; Peng, Min-Hua; Lee, Kung-Ta; Suzuki, Shino; Suzuki, Tadahiro; Oyaizu, Hiroshi

2011-07-01

339

Normas Chilenas para el MACI: Una Integración de Criterios Categoriales y Dimensionales1 Chilean Norms for MACI: An Integration of Categorical and Dimensional Criteria  

Microsoft Academic Search

Resumen Este estudio desarrolló normas chilenas para el Inventario Clínico para Adolescentes de Millon (MACI) utilizando una muestra de baremación diferenciada por sexo y dicotomizada en dos grupos, no-consultantes (200 hombres y 206 mujeres) y consultantes (212 hombres y 189 mujeres), que respondió el MACI y el MMPI-A. Con los datos MACI se desarrolló un conjunto de análisis estadísticos de

Eugenia V. Vinet

2008-01-01

340

An apparatus to control and monitor the para-D 2 concentration in a solid deuterium, superthermal source of ultra-cold neutrons  

NASA Astrophysics Data System (ADS)

Controlling and measuring the concentration of para-D 2 is an essential step toward realizing solid deuterium as an intense ultra-cold neutron source. To this end, we implemented an experimental technique to convert para- to ortho-deuterium molecules by flowing D 2 gas through a cryogenic cell filled with paramagnetic hydrous ferric oxide granules. This process efficiently reduced the para-D 2 concentration from 33.3% to 1.5%. Rotational Raman spectroscopy was applied to measure the residual para-D 2 contamination to better than 2 parts in 10 3, and the hydrogen contamination to 1 part in 10 3. We also contrast our optical technique to conventional thermal conductivity measurements of the para-D 2 concentration, reporting some of the relevant strengths and weaknesses of our implementation of each technique.

Liu, C.-Y.; Lamoreaux, S. K.; Saunders, A.; Smith, D.; Young, A. R.

2003-08-01

341

Propuesta de un m‚todo para la elecci¢n de buenas alternativas para la localizaci¢n de empresas de reciclaje de RAEE en Espa¤a  

Microsoft Academic Search

Ante la necesidad de Espa¤a de instalar nuevas empresas de reciclaje de RAEE, este trabajo proporciona a los agentes decisores una ordenaci¢n de los principales municipios espa¤oles seg£n su apropiabilidad para la instalaci¢n de estas empresas. Desarrolla un procedimiento que consiste en la identificaci¢n de los factores relevantes que deben tenerse en cuenta y en la posterior aplicaci¢n de una

Dolores Queiruga; Javier Gonz lez Benito; Grit Walther; Thomas Spengler

2004-01-01

342

Characterization of a para -nitrophenol catabolic cluster in Pseudomonas sp. strain NyZ402 and construction of an engineered strain capable of simultaneously mineralizing both para - and ortho -nitrophenols  

Microsoft Academic Search

Pseudomonas sp. strain NyZ402 was isolated for its ability to grow on para-nitrophenol (PNP) as a sole source of carbon, nitrogen, and energy, and was shown to degrade PNP via an oxidization pathway.\\u000a This strain was also capable of growing on hydroquinone or catechol. A 15, 818 bp DNA fragment extending from a 800-bp DNA\\u000a fragment of hydroxyquinol 1,2-dioxygenase gene (pnpG)

Qing WeiHong; Hong Liu; Jun-Jie Zhang; Song-He Wang; Yi Xiao; Ning-Yi Zhou

2010-01-01

343

Liquid chromatographic determination of para-toluenesulfonamide in edible fillet tissues from three species of fish  

USGS Publications Warehouse

Chloramine-T (N-sodium-N-chloro-p-toluene-sulfonamide) is a candidate therapeutic drug for treating bacterial gill disease, a predominant disease of a variety of fish species. Research has been initiated to obtain the U.S. Food and Drug Administration's (FDA) approval for the use of chloramine-T on a variety of fish species. An attribute of a therapeutic aquaculture drug that must be characterized before the FDA approves its use is depletion of the drug's marker residue (the drug's parent compound or metabolite of highest concentration in an edible tissue). Para-Toluenesulfonamide (p-TSA) is the primary degradation product and marker residue for chloramine-T in rainbow trout. To conduct residue depletion studies for chloramine-T in fish, a robust analytical method sensitive and specific for p-TSA residues in edible fillet tissue from a variety of fish was required. Homogenized fillet tissues from rainbow trout (Oncorhynchus mykiss), walleye (Stizostedion vitreum), and channel catfish (Ictalurus punctatus) were fortified at nominal p-TSA concentrations of 17, 67, 200, 333, and 1000 ng/g. Samples were analyzed by isocratic reversed-phase liquid chromatography (LC) with absorbance detection at 226 nm. Mean recoveries of p-TSA ranged from 77 to 93.17%; relative standard deviations ranged from 1.5 to 14%; method quantitation limits ranged from 13 to 18 ng/g; and method detection limits ranged from 3.8 to 5.2 ng/g. The LC parameters produced p-TSA peaks without coelution of endogenous compounds and excluded chromatographic interference from at least 20 chemicals and drugs of potential use in aquaculture.

Meinertz, J. R.; Schmidt, L. J.; Stehly, G. R.; Gingerich, W. H.

1999-01-01

344

High-strength poly(para-phenylene) as an orthopedic biomaterial.  

PubMed

Poly(para-phenylene) (PPP) exhibits exceptional mechanical strength, stiffness, toughness, and chemical inertness, although it is not currently used in any biomedical applications. The purpose of this study is to serve as a preliminary investigation into the potential of PPP as a biomaterial in orthopedic load-bearing applications. Nuclear magnetic resonance (NMR) analysis confirmed a polymer structure composed of an aromatic backbone and side groups. Tensile PPP specimens along with samples from several other polymers often used for orthopedic applications were elongated to failure after being soaked in phosphate buffered saline (PBS) for 1 h, 1 day, 1 week, 2 weeks, 1 month, and more than 1 year. Results showed that PBS absorption of the PPP plateaued at 1 week at values of ?0.7 wt % and remained within one standard deviation when soaked for over 1 year. PBS absorption did not affect elastic modulus (5.0 GPa), yield strength (141 MPa), fracture strength (120 MPa) and strain-to-failure (17%) more than one standard deviation. Zero-to-tension fatigue testing established an endurance limit of approximately 35 MPa, which was relatively insensitive to frequency (1-10 Hz). Eagle's minimum essential medium (MEM) elution assay with fibroblasts confirmed that the PPP was noncytotoxic. Relative to other polymers used for load-bearing biomedical applications, PPP displays promising mechanical properties that remain stable in aqueous solution. Lastly, prototype PPP and polyetheretherketone (PEEK) bone plates were manufactured and tested, with the PPP plate showing a 38% higher maximum tensile load before failure. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3122-3129, 2014. PMID:24123879

Frick, Carl P; DiRienzo, Amy L; Hoyt, Anthony J; Safranski, David L; Saed, Mohand; Losty, Eric J; Yakacki, Christopher M

2014-09-01

345

Chelation Therapy of Manganese Intoxication with para-Aminosalicylic Acid (PAS) in Sprague-Dawley Rats  

PubMed Central

Para-aminosalicylic acid (PAS), an FDA-approved anti-tuberculosis drug, has been used successfully in the treatment of severe manganese (Mn)-induced Parkinsonism in humans (Jiang et al., JOEM 48:644, 2006). This study was conducted to explore the capability of PAS in reducing Mn concentrations in body fluids and tissues of Mn-exposed animals. Sprague-Dawley rats received daily intraperitoneally (i.p.) injections of 6 mg Mn/kg, 5 d/wk for 4 wks, followed by a daily subcutaneously (sc.) dose of PAS (100 and 200 mg/kg as the PAS-L and PAS-H group, respectively) for another 2, 3 or 6 wks. Mn exposure significantly increased the concentrations of Mn in plasma, red blood cells (RBC), cerebrospinal fluid (CSF), brain and soft tissues. Following PAS-H treatment for 3 wks, Mn levels in liver, heart, spleen and pancreas were significantly reduced by 25 to 33%, while 3 wks of PAS-L treatment did not show any effect. Further therapy with PAS-H for 6 wk reduced Mn levels in striatum, thalamus, choroid plexus, hippocampus and frontal cortex by 16 to 29% (p<0.05). Mn exposure greatly increased iron (Fe) and copper (Cu) concentrations in CSF, brain and liver. Treatment with PAS-H restored Fe and Cu levels comparable with control. These data suggest that PAS likely acts as a chelating agent to mobilize and remove tissue Mn. A high-dose and prolonged PAS treatment appears necessary for its therapeutic effectiveness.

Zheng, Wei; Jiang, Yue-Ming; Zhang, Yanshu; Jiang, Wendy; Wang, Xueqian; Cowan, Dallas M.

2008-01-01

346

Physical Activity and Sedentary Behaviors in Postpartum Latinas: Madres para la Salud  

PubMed Central

Purpose To describe the physical activity (PA) and sedentary behaviors of postpartum Latinas who are overweight or obese prior to initiating Madres para la Salud, a social-support mediated walking intervention to promote postpartum weight loss. Methods 139 postpartum (13.6 ± 7.7 weeks since childbirth) women (age = 28.3 ± 5.6 years and BMI = 29.7 ± 3.5 kg.m2), recruited from Phoenix area Latino-serving organizations completed the Stanford Brief Activity Survey (SBAS) and concurrently wore an accelerometer (AG) and a pedometer for 7-days, and kept a PA record (PAR). Results Most were classified as inactive and lightly active on the SBAS (51% inactive, 37% light, 11% moderate). Most time was spent in sedentary (512.0 ± 169.9 min.d?1) and light-intensity PA (242.4 ± 51.4 min.d?1) with less time in moderate-intensity lifestyle (78.3 ± 39.9 min.d?1), moderate-intensity walking (16.6 ± 14.4 min.d?1), and vigorous-intensity PA (0.34 ± 1.5 min.d?1). Pedometer steps.d?1 were low (total = 4,973 ± 2,202 steps; aerobic = 412 ± 774 steps) with most participants rated as sedentary (61%) or low-active (28.1%). Consistent with objective PA measures, PARs showed more time spent in light-intensity PAs such as home care, cooking, child- and self care tasks, occupation, religious events, and watching television. Conclusion By and large, the postpartum Latinas enrolled spent most of their day in low-intensity activity levels with little time spent in health-enhancing PA levels/behaviors. This demographic should be the focus of PA interventions to increase PA to health enhancing levels.

Ainsworth, Barbara E.; Keller, Colleen; Herrmann, Stephen; Belyea, Michael; Records, Kathryn; Nagle-Williams, Allison; Vega-Lopez, Sonia; Permana, Paska; Coonrod, Dean V.

2013-01-01

347

Nitration of endogenous para-hydroxyphenylacetic acid and the metabolism of nitrotyrosine.  

PubMed Central

Reactive nitrogen species, such as peroxynitrite, can nitrate tyrosine in proteins to form nitrotyrosine. Nitrotyrosine is metabolized to 3-nitro-4-hydroxyphenylacetic acid (NHPA), which is excreted in the urine. This has led to the notion that measurement of urinary NHPA may provide a time-integrated index of nitrotyrosine formation in vivo. However, it is not known whether NHPA is derived exclusively from metabolism of nitrotyrosine, or whether it can be formed by nitration of circulating para -hydroxyphenylacetic acid (PHPA), a metabolite of tyrosine. In the present study, we have developed a gas chromatography MS assay for NHPA and PHPA to determine whether or not NHPA can be formed directly by nitration of PHPA. Following the injection of nitrotyrosine, 0.5+/-0.16% of injected dose was recovered unchanged as nitrotyrosine, and 4.3+/-0.2% as NHPA in the urine. To determine whether or not NHPA could be formed by the nitration of PHPA, deuterium-labelled PHPA ([(2)H(6)]PHPA) was injected, and the formation of deuterated NHPA ([(2)H(5)]NHPA) was measured. Of the infused [(2)H(6)]PHPA, 78+/-2% was recovered in the urine unchanged, and approx. 0.23% was recovered as [(2)H(5)]NHPA. Since the plasma concentration of PHPA is markedly higher than free nitrotyrosine (approx. 400-fold), the nitration of high-circulating endogenous PHPA to form NHPA becomes very significant and accounts for the majority of NHPA excreted in urine. This is the first study to demonstrate that NHPA can be formed by nitration of PHPA in vivo, and that this is the major route for its formation.

Mani, Ali R; Pannala, Ananth S; Orie, Nelson N; Ollosson, Richard; Harry, David; Rice-Evans, Catherine A; Moore, Kevin P

2003-01-01

348

Genes, Enzymes, and Regulation of para-Cresol Metabolism in Geobacter metallireducens? †  

PubMed Central

In aerobic and facultatively anaerobic bacteria, the degradation of para-cresol (p-cresol) involves the initial hydroxylation to p-hydroxybenzyl alcohol by water catalyzed by the soluble, periplasmatic flavocytochrome p-cresol methylhydroxylase (PCMH; ?2?2 composition). In denitrifying bacteria the further metabolism proceeds via oxidation to p-hydroxybenzoate, the formation of p-hydroxybenzoyl-coenzyme A (CoA), and the subsequent dehydroxylation of the latter to benzoyl-CoA by reduction. In contrast, the strictly anaerobic Desulfobacterium cetonicum degrades p-cresol by addition to fumarate, yielding p-hydroxybenzylsuccinate. In this work, in vitro enzyme activity measurements revealed that the obligately anaerobic Geobacter metallireducens uses the p-cresol degradation pathway of denitrifying bacteria. Surprisingly, PCMH, which is supposed to catalyze both p-cresol hydroxylation and p-hydroxybenzyl alcohol oxidation to the corresponding aldehyde, was located in the membrane fraction. The ? subunit of the enzyme was present in two isoforms, suggesting an ????2 composition. We propose that the unusual asymmetric architecture and the membrane association of PCMH might be important for alternative electron transfer routes to either cytochrome c (in the case of p-cresol oxidation) or to menaquinone (in the case of p-hydroxybenzyl alcohol oxidation). Unusual properties of further enzymes of p-cresol metabolism, p-hydroxybenzoate-CoA ligase, and p-hydroxybenzoyl-CoA reductase were identified and are discussed. A proteomic approach identified a gene cluster comprising most of the putative structural genes for enzymes involved in p-cresol metabolism (pcm genes). Reverse transcription-PCR studies revealed a different regulation of transcription of pcm genes and the corresponding enzyme activities, suggesting the presence of posttranscriptional regulatory elements.

Peters, Franziska; Heintz, Dimitri; Johannes, Jorg; van Dorsselaer, Alain; Boll, Matthias

2007-01-01

349

Origin of the bimodal island size distribution in ultrathin films of para-hexaphenyl on mica  

NASA Astrophysics Data System (ADS)

Ultrathin films of para-hexaphenyl (6P) were prepared on freshly cleaved and sputter-amorphized mica(001) by physical vapor deposition. Ex situ atomic force microscopy (AFM) revealed a bimodal island size distribution for the films on both surfaces. On freshly cleaved mica long needlelike islands exist, which are surrounded by small crystallites. On the sputter-amorphized substrates, large dendritic islands exist which are again surrounded by small, compact islands. We could prove by thermal desorption spectroscopy that the small islands are the result of adsorbate-induced subsequent nucleation, when the films were exposed to air. In case of the freshly cleaved mica, islands grow on a wetting layer in vacuum. This layer dewets and forms the small islands upon venting, due to the adsorption of water. In the case of the amorphous mica substrate an equilibrium exists between the islands and a two-dimensional gas phase in the sub-monolayer regime. Again, the latter phase nucleates after venting. In a particular coverage range, islands due to nucleation during deposition and subsequent nucleation coexist on the substrate, leading to the bimodal island size distribution. Kinetic Monte Carlo (KMC) simulations were performed to model the nucleation process after venting on the sputter-modified mica substrate. The density of the subsequently nucleated islands just depends on the initial coverage and the critical island size. A critical cluster size of i = 7 molecules was determined for 6P on amorphized mica, by comparing the KMC results with the AFM images in case of adsorbate-induced nucleation. Furthermore, the experimentally obtained island size distributions could be well reproduced by KMC simulations.

Tumbek, L.; Gleichweit, C.; Zojer, K.; Winkler, A.

2012-08-01

350

Tyrosine-lipid peroxide adducts from radical termination: para coupling and intramolecular Diels-Alder cyclization.  

PubMed

Free radical co-oxidation of polyunsaturated lipids with tyrosine or phenolic analogues of tyrosine gave rise to lipid peroxide-tyrosine (phenol) adducts in both aqueous micellar and organic solutions. The novel adducts were isolated and characterized by 1D and 2D NMR spectroscopy as well as by mass spectrometry (MS). The spectral data suggest that the polyunsaturated lipid peroxyl radicals give stable peroxide coupling products exclusively at the para position of the tyrosyl (phenoxy) radicals. These adducts have characteristic (13)C chemical shifts at 185 ppm due to the cross-conjugated carbonyl of the phenol-derived cyclohexadienone. The primary peroxide adducts subsequently undergo intramolecular Diels-Alder (IMDA) cyclization, affording a number of diastereomeric tricyclic adducts that have characteristic carbonyl (13)C chemical shifts at ~198 ppm. All of the NMR HMBC and HSQC correlations support the structure assignments of the primary and Diels-Alder adducts, as does MS collision-induced dissociation data. Kinetic rate constants and activation parameters for the IMDA reaction were determined, and the primary adducts were reduced with cuprous ion to give a phenol-derived 4-hydroxycyclohexa-2,5-dienone. No products from adduction of peroxyls at the phenolic ortho position were found in either the primary or cuprous reduction product mixtures. These studies provide a framework for understanding the nature of lipid-protein adducts formed by peroxyl-tyrosyl radical-radical termination processes. Coupling of lipid peroxyl radicals with tyrosyl radicals leads to cyclohexenone and cyclohexadienone adducts, which are of interest in and of themselves since, as electrophiles, they are likely targets for protein nucleophiles. One consequence of lipid peroxyl reactions with tyrosyls may therefore be protein-protein cross-links via interprotein Michael adducts. PMID:21090613

Shchepin, Roman; Möller, Matias N; Kim, Hye-young H; Hatch, Duane M; Bartesaghi, Silvina; Kalyanaraman, Balaraman; Radi, Rafael; Porter, Ned A

2010-12-15

351

High stroke volume para-aortic counterpulsation device versus centrifugal pump in cardiogenic shock: experimental study.  

PubMed

During the last decades a number of left ventricular assist devices has been used especially for patients resistant to pharmacologic treatment and to intraaortic balloon pump (IABP) support for left ventricular failure. A high stroke volume para-aortic counterpulsation device (PACD) has been developed utilizing the principle of the diastolic counterpulsation technique. In this study the hemodynamic effects of the valveless PACD were compared to those of the centrifugal blood pump (CBP) in nine dogs in acute experimental cardiogenic shock. Hemodynamic measurements were obtained at baseline with both devices off, PACD on and CBP off, or PACD off and CBP on. There was no difference in mean aortic pressure between PACD on (60.0 +/- 11.5 mmHg) and CBP on (69.0 +/- 26.8 mmHg). Similarly, there was no difference in left ventricular end-diastolic pressure with the PACD on (11.9 +/- 5.4 mmHg) versus the CBP on (9.9 +/- 5.2 mmHg) or the cardiac index with the PACD on (84 +/- 36 ml/kg/min) versus the CBP on (77 +/- 36 ml/kg/min). However, the left ventricular systolic pressure (55.0 +/- 19.0 with PACD versus 73.0 +/- 26.0 with CBP,p < 0.001), the tension time index (712 +/- 381 versus 1333 +/- 694,p < 0.01), and the double product (5629 +/- 2574 versus 7440 +/- 3294,p < 0.01) were significantly lower during assistance with the PACD than with the CBP. It was concluded that PACD is at least as effective as CBP for restoring hemodynamic status during acute experimental cardiogenic shock. Moreover, the PACD unloads the left ventricle more effectively than CBP, making it suitable for left ventricular mechanical support in cases with reversible myocardial damage. PMID:9015178

Nanas, S N; Nanas, J N; Charitos, C E; Gougoulakis, A; Makaritsis, K; Chatzigeorgiou, J; Moussoutzani, K; Anastasiou-Nana, M I; Moulopoulos, S D

1997-01-01

352

Introduccion a la hidraulica de aguas subterraneas : un texto programado para auto-ensenanza  

USGS Publications Warehouse

Este ' texto programado esta diseflado para ayudarle a comprender la teoria de la hidniulica de aguas subterraneas por medio de la auto-enseflanza. La instrucci6n programada es un enfoque a una materia, un metodo de aprender;que no elimina el esfuerzo mental del proceso de aprendizaje. Algunas secciones de este programa necesitan solamente ser leidas; otras tendrian que ser elaboradas con lapiz y papel. Algunas preguntas pueden ser contestadas directamente; otras requieren calculos. A medida que se avanza en el texto, tendra que consultar frecuentemente textos o referencias sobre matematicas, mecanica de fluidos e hidrologia. En cada una de las ocho partes del texto, inicie el programa de instrucci6n leyendo la Secci6n 1. Elija una respuesta a la pregunta al final de la secci6n y dirijase a la nueva secci6n indicada al lado de la respuesta escogida. Si su respuesta fue correcta, pase a la secci6n que contiene materia nueva y otra pregunta, y proceda tal como en la Secci6n 1. Si su respuesta no fue correcta, dirijase a la secci6n que contiene explicaciones adicionales sobre el tema anterior y que le indica volver a la pregunta inicial e intentar de nuevo. En este caso, valdra Ia pena repasar el material de la secci6n anterior. Continue de esta man era en el programa hasta que llegue a Ia secci6n que indica el final de la parte. Observe que aunque las secciones estan en orden numerico en cada una de las ocho partes, por lo general, usted no procedeni en secuencia numerica (Secci6n 1 ala Secci6n 2, etc.) de principia a fin.

Bennett, Gordon D.

1987-01-01

353

Membrane Potential-Dependent Inhibition of the Na+,K+-ATPase by para-Nitrobenzyltriethylammonium Bromide  

PubMed Central

Membrane potential (VM)-dependent inhibitors of the Na+,K+-ATPase are a new class of compounds that may have inherent advantages over currently available drugs targeting this enzyme. However, two questions remain unanswered regarding these inhibitors: (1) what is the mechanism of VM-dependent Na+,K+-ATPase inhibition, and (2) is their binding affinity high enough to consider them as possible lead compounds? To address these questions, we investigated how a recently synthesized VM-dependent Na+,K+-ATPase inhibitor, para-nitrobenzyltriethylamine (pNBTEA), binds to the enzyme by measuring the extracellular pNBTEA concentration and VM dependence of ouabain-sensitive transient charge movements in whole-cell patch-clamped rat cardiac ventricular myocytes. By analyzing the kinetics of charge movements and the steady-state distribution of charge, we show that the VM-dependent properties of pNBTEA binding differ from those for extracellular Na+ and K+ binding, even though inhibitor binding is competitive with extracellular K+. The data were also fit to specific models for pNBTEA binding to show that pNBTEA binding is a rate-limiting VM-dependent reaction that, in light of homology models for the Na+,K+-ATPase, we interpret as a transfer reaction of pNBTEA from a peripheral binding site in the enzyme to a site near the known K+ coordination sites buried within the transmembrane helices of the enzyme. These models also suggest that binding occurs with an apparent affinity of 7 ?M. This apparent binding affinity suggests that high-affinity VM-dependent Na+,K+-ATPase inhibitors should be feasible to design and test as specific enzyme inhibitors.

Peluffo, R. Daniel

2012-01-01

354

On the mode-coupling treatment of collective density fluctuations for quantum liquids: para-hydrogen and normal liquid helium.  

PubMed

A novel quantum mode coupling theory combined with a kinetic approach is developed for the description of collective density fluctuations in quantum liquids characterized by Boltzmann statistics. Three mode-coupling approximations are presented and applied to study the dynamic response of para-hydrogen near the triple point and normal liquid helium above the ?-transition. The theory is compared with experimental results and to the exact imaginary time data generated by path integral Monte Carlo simulations. While for liquid para-hydrogen the combination of kinetic and quantum mode-coupling theory provides semi-quantitative results for both short and long time dynamics, it fails for normal liquid helium. A discussion of this failure based on the ideal gas limit is presented. PMID:21280769

Kletenik-Edelman, Orly; Reichman, David R; Rabani, Eran

2011-01-28

355

X-ray photoelectron spectroscopy study of para-substituted benzoic acids chemisorbed to aluminum oxide thin films  

SciTech Connect

A series of para-substituted, halogenated (F, Cl, Br, and I) benzoic acid monolayers were prepared on the native oxide of aluminum surfaces by solution self-assembly and spin-coating techniques. The monolayers were characterized by x-ray photoelectron spectroscopy (XPS) and water contact angles. Several general trends are apparent. First, the polarity of the solvent is critical to monolayer formation. Protic polar solvents produced low coverage monolayers; in contrast, nonpolar solvents produced higher coverage monolayers. Second, solution deposition yields a higher surface coverage than spin coating. Third, the thickness of the monolayers determined from XPS suggests the plane of the aromatic ring is perpendicular to the surface with the carboxylate functional group most likely binding in a bidentate chelating geometry. Fourth, the saturation coverage (?2.7 × 10{sup 14} molecules cm{sup ?2}) is independent of the para-substituent.

Kreil, Justin; Ellingsworth, Edward; Szulczewski, Greg [Department of Chemistry, The University of Alabama, Shelby Hall, 250 Hackberry Lane, Tuscaloosa, Alabama 35487 (United States)] [Department of Chemistry, The University of Alabama, Shelby Hall, 250 Hackberry Lane, Tuscaloosa, Alabama 35487 (United States)

2013-11-15

356

Electron-Donating Para-Methoxy Converts a Benzamide-Isoquinoline Derivative into a Highly Sigma-2 Receptor Selective Ligand  

PubMed Central

The sigma-2 (?2) receptor has been suggested to be a promising target for pharmacological interventions to curb tumor progression. Development of ?2-specific ligands, however, has been hindered by lack of understanding of molecular determinants that underlie selective ligand-?2 interactions. Here we have explored effects of electron donating and withdrawing groups on ligand selectivity for the ?2 versus ?1 receptor using new benzamide-isoquinoline derivatives. The electron-donating methoxy group increased but the electron-withdrawing nitro group decreased ?2 affinity. In particular, an extra methoxy added to the para-position (5e) of the benzamide phenyl ring of 5f dramatically improved (631 fold) the ?2 selectivity relative to the ?1 receptor. This para-position provided a sensitive site for effective manipulation of the sigma receptor subtype selectivity using either the methoxy or nitro substituent. Our study provides a useful guide for further improving the ?2-over-?1 selectivity of new ligands.

Hajipour, Abdol R.; Guo, Lian-Wang; Pal, Arindam; Mavlyutov, Timur; Ruoho, Arnold E.

2011-01-01

357

Trends in electron-ion dissociative recombination of benzene analogs with functional group substitutions: Negative Hammett ?para values  

NASA Astrophysics Data System (ADS)

An in-depth study of the effects of functional group substitution on benzene's electron-ion dissociative recombination (e-IDR) rate constant has been conducted. The e-IDR rate constants for benzene, biphenyl, toluene, ethylbenzene, anisole, phenol, and aniline have been measured using a Flowing Afterglow equipped with an electrostatic Langmuir probe (FALP). These measurements have been made over a series of temperatures from 300 to 550 K. A relationship between the Hammett ?para values for each compound and rate constant has indicated a trend in the e-IDR rate constants and possibly in their temperature dependence data. The Hammett ?para value is a method to describe the effect a functional group substituted to a benzene ring has upon the reaction rate constant.

Osborne, David; Lawson, Patrick Andrew; Adams, Nigel; Dotan, Itzhak

2014-06-01

358

Long-term survival after resection of pancreatic ductal adenocarcinoma with para-aortic lymph node metastasis: case report  

PubMed Central

Pancreatic cancer patients with para-aortic lymph node metastasis have a poor prognosis and patients living longer than 3 years are rare. We had a patient with pancreatic cancer who survived for more than 10 years after removal of the para-aortic lymph node metastasis. A 57-year-old woman was diagnosed with pancreatic head cancer and underwent a pancreaticoduodenectomy with subtotal gastric resection following Whipple reconstruction in 2000. Para-aortic lymph node metastasis was detected during the operation by intraoperative pathological diagnosis and an extended lymphadenectomy was performed with vascular skeletonization of the celiac and superior mesenteric arteries. In 2004, a low-density area was detected around the superior mesenteric artery (SMA) 5 cm from its root and she was treated with gemcitabine, and the area was undetectable after 3 years of treatment. In 2010, computed tomography showed a low-density area around the same lesion with an increased carcinoembryonic antigen level. After 4 months of gemcitabine treatment, we resected the tumor en bloc with the associated superior mesenteric vein and perineural tissue. Histopathological examination of the resected specimen revealed a well-differentiated tubular adenocarcinoma that closely resembled the original primary pancreatic cancer, indicating perineural recurrence 10 years after the initial resection. She had no recurrence around the SMA for more than one year. Although a meta-analysis has not proved the efficacy of preventive radical dissection, this case indicates that a patient with well-differentiated, chemotherapy-responsive pancreatic cancer with para-aortic lymph node metastasis could have a long survival time through extended dissection of the lymph nodes.

2013-01-01

359

Dysregulation in retinal para-inflammation and age-related retinal degeneration in CCL2 or CCR2 deficient mice.  

PubMed

We have shown previously that a para-inflammatory response exists at the retinal/choroidal interface in the aging eye; and this response plays an important role in maintaining retinal homeostasis under chronic stress conditions. We hypothesized that dysregulation of the para-inflammatory response may result in an overt pro-inflammatory response inducing retinal degeneration. In this study, we examined this hypothesis in mice deficient in chemokine CCL2 or its cognate receptor CCR2. CCL2- or CCR2-deficient mice developed retinal degenerative changes with age, characterized as retinal pigment epithelial (RPE) cell and photoreceptor cell death. Retinal cell death was associated with significantly more subretinal microglial accumulation and increased complement activation. In addition, monocytes from CCL2- or CCR2-deficient mice had reduced capacity for phagocytosis and chemotaxis, expressed less IL-10 but more iNOS, IL-12 and TNF-? when compared to monocytes from WT mice. Complement activation at the site of RPE cell death resulted in C3b/C3d but not C5b-9 deposition, indicating only partial activation of the complement pathway. Our results suggest that altered monocyte functions may convert the protective para-inflammatory response into an overtly harmful inflammation at the retina/choroidal interface in CCL2- or CCR2-deficient mice, leading to RPE and photoreceptor degeneration. These data support a concept whereby a protective para-inflammatory response relies upon a normally functioning innate immune system. If the innate immune system is deficient chronic stress may tip the balance towards an overt inflammatory response causing cell/tissue damage. PMID:21850237

Chen, Mei; Forrester, John V; Xu, Heping

2011-01-01

360

Increasing the Analytical Sensitivity by Oligonucleotides Modified with Para- and Ortho-Twisted Intercalating Nucleic Acids - TINA  

PubMed Central

The sensitivity and specificity of clinical diagnostic assays using DNA hybridization techniques are limited by the dissociation of double-stranded DNA (dsDNA) antiparallel duplex helices. This situation can be improved by addition of DNA stabilizing molecules such as nucleic acid intercalators. Here, we report the synthesis of a novel ortho-Twisted Intercalating Nucleic Acid (TINA) amidite utilizing the phosphoramidite approach, and examine the stabilizing effect of ortho- and para-TINA molecules in antiparallel DNA duplex formation. In a thermal stability assay, ortho- and para-TINA molecules increased the melting point (Tm) of Watson-Crick based antiparallel DNA duplexes. The increase in Tm was greatest when the intercalators were placed at the 5? and 3? termini (preferable) or, if placed internally, for each half or whole helix turn. Terminally positioned TINA molecules improved analytical sensitivity in a DNA hybridization capture assay targeting the Escherichia coli rrs gene. The corresponding sequence from the Pseudomonas aeruginosa rrs gene was used as cross-reactivity control. At 150 mM ionic strength, analytical sensitivity was improved 27-fold by addition of ortho-TINA molecules and 7-fold by addition of para-TINA molecules (versus the unmodified DNA oligonucleotide), with a 4-fold increase retained at 1 M ionic strength. Both intercalators sustained the discrimination of mismatches in the dsDNA (indicated by ?Tm), unless placed directly adjacent to the mismatch – in which case they partly concealed ?Tm (most pronounced for para-TINA molecules). We anticipate that the presented rules for placement of TINA molecules will be broadly applicable in hybridization capture assays and target amplification systems.

Schneider, Uffe V.; Geci, Imrich; J?hnk, Nina; Mikkelsen, Nikolaj D.; Pedersen, Erik B.; Lisby, Gorm

2011-01-01

361

Synthesis and characterization of novel photochromic side-chain liquid crystalline polymethacrylates containing para-nitroazobenzene group  

Microsoft Academic Search

Methacrylate monomers containing a mesogenic group and a photochromic para-nitroazobenzene group were prepared and polymerized in tetrahydrofuran (THF) using 2,2?-azobis(isobutyronitrile) (AIBN) as initiator at 67°C. The polymers were characterized by 1H NMR, IR, UV-Vis spectra and elemental analyses. The molecular weights Mw and Mn of the polymers were determined by gel permeation chromatography (GPC). The thermal properties of the polymers

Hui-Qi Zhang; Wen-Qiang Huang; chen-xi li; Bing-Lin He

1998-01-01

362

Cloning and functional analysis of tipE, a novel membrane protein that enhances drosophila para sodium channel function  

Microsoft Academic Search

Voltage-dependent sodium channels are involved in the initiation and propagation of action potentials in many excitable cells. Here we report that tipE, a gene defined by a temperature-sensitive paralytic mutation in Drosophila, encodes a novel integral membrane protein that dramatically stimulates functional expression in Xenopus oocytes of the Drosophila sodium channel ? subunit encoded by the paralytic (para) locus. Using

Guoping Feng; Péter Deak; Maninder Chopra; Linda M Hall

1995-01-01

363

Four novel sequences in Drosophila melanogaster homologous to the auxiliary Para sodium channel subunit TipE  

Microsoft Academic Search

TipE is an auxiliary subunit of the Drosophila Para sodium channel. Here we describe four sequences, TEH1-4, homologous to TipE in the Drosophila melanogaster genome, harboring all typical structures of both TipE and the ?-Subunit family of big-conductance Ca2+-activated potassium channels: short cytosolic N- and C-terminal stretches, two transmembrane domains, and a large extracellular loop with two disulfide bonds. Whereas

Christian Derst; Christian Walther; Rüdiger W. Veh; Dieter Wicher; Stefan H. Heinemann

2006-01-01

364

Se da a conocer el plan del Instituto Nacional del Cáncer para acelerar la investigación del cáncer  

Cancer.gov

En la 100va Reunión Anual de la Asociación Estadounidense de Investigación del Cáncer realizada en Denver, el director del Instituto Nacional del Cáncer, doctor John E. Niederhuber, dio a conocer detalles importantes, tales como financiamiento de más subvenciones, creación de una plataforma para atención personalizada del cáncer y un programa acelerado de genética del cáncer que hará avanzar la investigación oncológica en este nuevo ambiente económico.

365

Characterization and mutagenesis of a two-component monooxygenase involved in para-nitrophenol degradation by an Arthrobacter strain  

Microsoft Academic Search

para-Nitrophenol (PNP) degradation cluster was cloned from a newly isolated Arthrobacter sp. strain NyZ415 by genome walking extending from a conserved region of gene encoding the oxygenase component of PNP monooxygenase. Sequence analysis indicated it contained 12 open reading frames including genes npdA1 and npdA2 which encoded the reductase and oxygenase components of PNP monooxygenase, respectively. Both NpdA1 and NpdA2

Ping-Ping Liu; Jun-Jie Zhang; Ning-Yi Zhou

2010-01-01

366

Genetic Heterogeneities and Phenotypic Characteristics of Strains of the Genus Abiotrophia and Proposal of Abiotrophia para-adiacens sp. nov.  

PubMed Central

The genus Abiotrophia represents a heterogeneous group of fastidious cocci that show a dependence on pyridoxal hydrochloride analogs for growth. The genetic heterogeneity in the genus Abiotrophia was examined by DNA-DNA hybridization, PCR assay of genomic DNA sequences, and restriction fragment length polymorphism and sequence homology analyses of the PCR-amplified 16S rRNA gene. Nine type or reference strains of Abiotrophia defectiva, Abiotrophia adiacens, and Abiotrophia elegans and 36 oral Abiotrophia isolates including the ones presumptively identified as Gemella morbillorum by the rapid ID32 STREP system were divided into four groups: A. defectiva (genotype 1), A. adiacens (genotype 2), A. elegans (genotype 4), and a fourth species (genotype 3) which we propose be named Abiotrophia para-adiacens sp. nov. A PCR assay specific for detection and identification of the novel Abiotrophia species was developed. A. para-adiacens generally produced ?-glucosidase but did not produce ?- or ?-galactosidase or arginine dihydrolase, did not ferment, trehalose, pullulan, or tagatose, and was serotype IV, V, or VI. Thus, it was distinguished phenotypically from A. adiacens, A. elegans, and A. defectiva as well as, apparently, from the recently described species Abiotrophia balaenopterae sp. nov., which produces arginine dihydrolase and which ferments pullulan but not sucrose (P. A. Lawson et al., Int. J. Syst. Bacteriol. 49:503–506, 1999). Strain ATCC 27527, currently listed as G. morbillorum, was a member of the species A. para-adiacens.

Kanamoto, Taisei; Sato, Setsuko; Inoue, Masakazu

2000-01-01

367

Comparison between limbal (von Noorden) and para limbal (Santiago) conjunctival incisions for adjustable recessions of horizontal recti.  

PubMed

Introduction: Both limbal and para limbal conjunctival incisions are routinely used in strabismus surgery with comparable results however their outcome has not been compared while using adjustable sutures. Objective: To compare limbal (von Noorden) and para limbal (Santiago) conjunctival incisions for adjustable recessions of horizontal recti. Subjects and methods: Uniocular adjustable recessions (with conventional non adjustable resection) in 24 appropriate patients were performed according to standard slip knot technique. The patients were assigned to the two groups after obtaining an informed consent using systematmic randomization. Twelve patients in first group received the von Noorden incision with bare sclera closure and 12 in the second group received the Santiago's modification of Swan incision with deferred closure. The surgeries were performed by a single surgeon and the adjustments performed after 24 hours. The incisions were studied on the established subjective (pain) and objective (hyperaemia, chemosis, discharge and gap in incision) variables at follow ups of 1st day post adjustment, 2 weeks and 12 weeks. Statistics: 'Repeated Measures Anova' test was used for statistical analysis. A p value Less than 0.05 was considered statistically significant. Results: The limbal incision was superior to the paralimbal incision on both objective and subjective criteria by 'Repeated Measures Anova' test. Conclusion: We recommend using limbal incision and avoiding para limbal incisions while performing adjustable recessions. PMID:24172558

Agrawal, S; Singh, V; Gupta, S K; Agrawal, S

2013-07-01

368

The vitamin-like dietary supplement para-aminobenzoic acid enhances the antitumor activity of ionizing radiation  

SciTech Connect

Purpose: To determine whether para-aminobenzoic acid (PABA) alters the sensitivity of tumor cells to ionizing radiation in vitro and in vivo. Methods and Materials: Cellular proliferation was assessed by WST-1 assays. The effects of PABA and radiation on tumor growth were examined with chick embryo and murine models. Real-time reverse transcriptase-polymerase chain reaction and Western blotting were used to quantify p21{sup CIP1} and CDC25A levels. Results: Para-aminobenzoic acid enhanced (by 50%) the growth inhibitory activity of radiation on B16F10 cells, whereas it had no effect on melanocytes. Para-aminobenzoic acid enhanced (50-80%) the antitumor activity of radiation on B16F10 and 4T1 tumors in vivo. The combination of PABA and radiation therapy increased tumor apoptosis. Treatment of tumor cells with PABA increased expression of CDC25A and decreased levels of p21{sup CIP1}. Conclusions: Our findings suggest that PABA might represent a compound capable of enhancing the antitumor activity of ionizing radiation by a mechanism involving altered expression of proteins known to regulate cell cycle arrest.

Xavier, Sandhya [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); MacDonald, Shannon [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Roth, Jennifer [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Caunt, Maresa [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Akalu, Abebe [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Morais, Danielle [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Buckley, Michael T. [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Liebes, Leonard [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Formenti, Silvia C. [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States); Brooks, Peter C. [Departments of Radiation Oncology and Cell Biology, NYU Cancer Institute, New York University School of Medicine, New York, NY (United States)]. E-mail: peter.brooks@med.nyu.edu

2006-06-01

369

Quantum effects of translational motions in solid para-hydrogen and ortho-deuterium: anharmonic extension of the Einstein model.  

PubMed

An anharmonic extension of the Einstein model is developed in order to describe the effect of translational zero point motion on structural and thermodynamic properties of para-H(2) and ortho-D(2) crystals in the zero temperature limit. Accordingly, the molecules carry out large amplitude translational motions in their matrix cage, which are formed by the frozen environment of all other molecules. These translations lead from the molecular equilibrium positions via the harmonic to the anharmonic domain of the potential energy surface. The resulting translational distributions are roughly isotropic, and they have approximately Gaussian shapes, with rather broad full widths at half-maximum, FWHM(para-H(2)/ortho-D(2)) = 1.36/1.02 Å. The translational zero point energies induce expansions of the crystals, in nearly quantitative agreement with experimental results. Furthermore, they make significant contributions to the sublimation energies and zero pressure bulk moduli. These quantum effects decrease with heavier molecular masses. The corresponding isotope effects for ortho-D(2) compared to para-H(2) are confirmed by application of the model to Ar crystals. The results imply consequences for laser induced reaction dynamics of dopants with their host crystals. PMID:21389514

Kühn, O; Manz, J; Schild, A

2010-04-01

370

Para-Grassmannian Coherent and Squeezed States for Pseudo-Hermitian q-Oscillator and their Entanglement  

NASA Astrophysics Data System (ADS)

In this paper, q-deformed oscillator for pseudo-Hermitian systems is investigated and pseudo-Hermitian appropriate coherent and squeezed states are studied. Also, some basic properties of these states is surveyed. The over-completeness property of the para-Grassmannian pseudo-Hermitian coherent states (PGPHCSs) examined, and also the stability of coherent and squeezed states discussed. The pseudo-Hermitian supercoherent states as the product of a pseudo-Hermitian bosonic coherent state and a para-Grassmannian pseudo-Hermitian coherent state introduced, and the method also developed to define pseudo-Hermitian supersqueezed states. It is also argued that, for q-oscillator algebra of k+1 degree of nilpotency based on the changed ladder operators, defined in here, we can obtain deformed SUq2(2) and SUq2k(2) and also SUq2k(1,1). Moreover, the entanglement of multi-level para-Grassmannian pseudo-Hermitian coherent state will be considered. This is done by choosing an appropriate weight function, and integrating over tensor product of PGPHCSs.

Maleki, Yusef

2011-08-01

371

Layered material gamma-ZrP supported platinum catalyst for liquid-phase reaction: a highly active and selective catalyst for hydrogenation of the nitro group in para-chloronitrobenzene.  

PubMed

Chemoselective hydrogenation of para-chloronitrobenzene without any dechlorination over Pt/gamma-ZrP catalyst proceeds effectively, which provides a clean and convenient approach to produce useful para-chloroaniline with excellent activity and selectivity. PMID:18536814

Wang, Fang; Liu, Junhua; Xu, Xianlun

2008-05-01

372

3-(7-Dimethylamino)coumarin N-phenylsemicarbazones in solution and polymer matrices: Tuning their fluorescence via para-phenyl substitution  

NASA Astrophysics Data System (ADS)

The photo-physical properties of five new para-phenyl substituted derivatives of 3-(7-dimethylamino)coumarin N-phenylsemicarbazone with various electron-withdrawing substituents R (Rdbnd F, Br, CF3, CN or NO2) in the para-position on the phenyl ring were investigated in solvents and in polymer matrices. Tuning their fluorescent properties via para-substitution is discussed in terms of Twisted Intra-molecular Charge-Transfer (TICT) state formation, specific solute-solvent interactions (hydrogen bonding), fluorescent H-aggregates formation, and the solvent polarity and polymer matrix effects.

Cigá?, Marek; Danko, Martin; Donovalová, Jana; Gašpar, Jan; Stankovi?ová, Henrieta; Gáplovský, Anton; Hrdlovi?, Pavol

373

Infrared Spectra of the 2-CHLOROETHYL Radical in Solid Para-Hydrogen  

NASA Astrophysics Data System (ADS)

The reaction of chlorine atoms with ethylene and two of its deuterium isotopomers in solid para-hydrogen (p-H2) matrices at 3 K has been studied using infrared spectroscopy. Irradiation at 365 nm of a co-deposited mixture of Cl2, C2H4, and p-H2 at 3 K produces a series of new lines in the infrared spectrum. Several of the new lines are readily assigned to the gauche and trans conformers of 1,2-dichloroethane (CH2ClCH2Cl) resulting from the addition of two Cl atoms to C2H4. Of the remaining lines, a strong line at 664 Cm-1 and three weaker lines at 562, 1070, and 1228 Cm-1 are concluded to be due to a single carrier based on their behavior upon subsequent annealing to 4.5 K and irradiation at 254 and 214 nm. When the positions and intensities of these lines are compared to the MP2/aug-cc-pVDZ predicted vibrational spectra of the possible species that could result from the addition and abstraction reactions of one Cl atom with C2H4, the best agreement is found with the 2-chloroethyl radical (CdotCH2CH2Cl). In order to confirm this assignment, isotopic experiments were performed with C2D4 and t-C2H2D2 and the corresponding infrared bands due to the deuterium isotopomers of this radical (CdotCD2CD2Cl and \\cdotCHDCHDCl) have been observed. A final set of experiments were performed following irradiation of the Cl2/C2H4/p-H2 mixture at 365 nm, in which the matrix was irradiated with filtered infrared light from a globar source, which has been shown to induce a reaction between isolated Cl atoms and matrix H2 to produce HCl and H atoms. In our experiments, the major products observed were HCl and ethyl chloride (CH3CH2Cl) and the possible mechanism of the formation of ethyl chloride will be discussed. P. Brana, B. Menendez, T. Fernandez, and J. A. Sordo, J. Phys. Chem. A 104, 10842 (2000) P. L. Raston and D. T. Anderson, Phys. Chem. Chem. Phys. 8, 3124 (2006)

Amicangelo, Jay C.; Bahou, Mohammed; Golec, Barbara; Lee, Yuan-Pern

2011-06-01

374

para-Aminobenzoic acid is a precursor in coenzyme Q6 biosynthesis in Saccharomyces cerevisiae.  

PubMed

Coenzyme Q (ubiquinone or Q) is a crucial mitochondrial lipid required for respiratory electron transport in eukaryotes. 4-Hydroxybenozoate (4HB) is an aromatic ring precursor that forms the benzoquinone ring of Q and is used extensively to examine Q biosynthesis. However, the direct precursor compounds and enzymatic steps for synthesis of 4HB in yeast are unknown. Here we show that para-aminobenzoic acid (pABA), a well known precursor of folate, also functions as a precursor for Q biosynthesis. A hexaprenylated form of pABA (prenyl-pABA) is normally present in wild-type yeast crude lipid extracts but is absent in yeast abz1 mutants starved for pABA. A stable (13)C(6)-isotope of pABA (p- amino[aromatic-(13)C(6)]benzoic acid ([(13)C(6)]pABA)), is prenylated in either wild-type or abz1 mutant yeast to form prenyl-[(13)C(6)]pABA. We demonstrate by HPLC and mass spectrometry that yeast incubated with either [(13)C(6)]pABA or [(13)C(6)]4HB generate both (13)C(6)-demethoxy-Q (DMQ), a late stage Q biosynthetic intermediate, as well as the final product (13)C(6)-coenzyme Q. Pulse-labeling analyses show that formation of prenyl-pABA occurs within minutes and precedes the synthesis of Q. Yeast utilizing pABA as a ring precursor produce another nitrogen containing intermediate, 4-imino-DMQ(6). This intermediate is produced in small quantities in wild-type yeast cultured in standard media and in abz1 mutants supplemented with pABA. We suggest a mechanism where Schiff base-mediated deimination forms DMQ(6) quinone, thereby eliminating the nitrogen contributed by pABA. This scheme results in the convergence of the 4HB and pABA pathways in eukaryotic Q biosynthesis and has implications regarding the action of pABA-based antifolates. PMID:20592037

Marbois, Beth; Xie, Letian X; Choi, Samuel; Hirano, Kathleen; Hyman, Kyle; Clarke, Catherine F

2010-09-01

375

How Chlorine Atom Reacts with H2 in Ir-Irradiated Solid Para-Hydrogen  

NASA Astrophysics Data System (ADS)

The use of solid para-hydrogen ({p}-H2) as a matrix host has generated considerable interest in recent years. Solid {p}-H2 is considered as a quantum solid; hence it is "softer" than noble gas matrices and has several unique properties such as narrow bandwidths, feasibility of molecular and internal rotation, and a diminished cage effect, which is particularly relevant to the formation of atoms and radicals in a matrix using photolysis {in situ}. Raston and Anderson employed laser emission at 355 nm to photodissociate Cl2 trapped in solid {p}-H2 at 2 K and produced isolated Cl atoms. Excitation of the solid {p}-H2 with IR light in the range 4000-5000 cm-1 from a globar source induces reactions of Cl atoms with {p}-H2 to form HCl. We investigated the reaction of Cl with solid {p}-H2 with a tunable IR laser and a FTIR spectrometer. The Cl atoms were produced on irradiation of a Cl2/{p}-H2 (1/1000-1/4000) matrix with light at 365 nm from a light-emitting diode. By monitoring continuously the formation of HCl while tuning the wavelength of the IR laser, we obtained the relative yield of HCl as a function of excitation wavelength. We found that absorption of the Cl-H2 complex and solid H2, but not the Cl2-H2 complex, induced the reaction Cl + H2. In separate experiments we irradiated a selective area of the matrix with UV light and compared the yields of HCl in this area when we irradiated IR light at various locations. When the IR laser light irradiated outside the UV-irradiated area, excitation of {p}-H2 near 4229 cm-1, but not the Cl-H2 complex at 4148.5 cm-1, still produced HCl. In contrast, when the IR light irradiated inside the UV-irradiated region, more HCl was produced at 4148.5 cm-1. This indicates that the excited H2 can move around and react with Cl located far away from the originally excited area, whereas the IR excited Cl-H2 complex reacts directly to form HCl. We also found that irradiation of H2 produced some dimers of HCl, whereas irradiation at the Cl-H2 complex produced only HCl monomer. P. L. Raston and D. T. Anderson, J. Chem. Phys. 126, 021106 (2007). P. L. Raston and D. T. Anderson, Phys. Chem. Chem. Phys. 8, 3124 (2006).

Wu, Jen-Yu; Bahou, Mohammed; Lee, Yuan-Pern

2012-06-01

377

Extraction of titanium, chromium and cadmium from phosphoric acid solutions by para (1,1,3,3 tetramethyl butyl) phenyl phosphoric acid in kerosene diluent.  

National Technical Information Service (NTIS)

The distribution of titanium, chromium and cadmium between phosphoric acid solutions and solutions of para (1,1,3,3, tetramethyl butyl) phenyl phosphoric acid in kerosene diluent has been investigated under different conditions. The aqueous and organic ph...

A. Mellah D. Bauer

1993-01-01

378

Possible Derivations of Ortho- and Para-H2 Ratios in the Atmospheres of the Giant Planets Using the 2 ? m Spectral Structures of (H2)2  

NASA Astrophysics Data System (ADS)

We have presented an ab \\ initio model of the 2 ? m spectral features of (H2)2 based on the far-infrared models of McKellar & Schaefer (1991). We have shown that the intensity variations of the 2 ? m (H2)2 features depend on the ortho/para ratios of H2. We have discussed the applicability of the variations to the atmospheres of the giant planets for the derivations of the ortho/para ratios. The signal to noise ratios of currently available spectra of the giant planets are not sufficient enough to derive accurate ortho/para ratios of these planets. Observations with longer exposure times and larger telescope apertures are required to obtain better spectra for the derivations of the ortho/para ratios of H2 in the atmospheres of the giant planets.

Kim, Sang-Joon; Lee, Yong-Sik

2001-11-01

379

Study of the Radiation-Induced Crosslinking of a Butadiene-Acrylonitrile Polymer in the Presence of n-Para-Bromophenylmaleimide.  

National Technical Information Service (NTIS)

Mixtures of butadiene-acrylonitrile copolymer with N-para-bromophenyl-maleimide (crosslinking sensitizer) were irradiated by exposure to the gamma radiation of a exp 60 Co source. The kinetics of crosslinking was evaluated as a function of composition, do...

D. Cavagnat

1976-01-01

380

Electrochemical sensor based on a poly( para-aminobenzoic acid) film modified glassy carbon electrode for the determination of melamine in milk  

Microsoft Academic Search

A novel and simple sensor is developed in this paper for melamine detection, which is based on an electropolymerized molecularly imprinted polymer (MIP) of para-aminobenzoic acid (pABA). The poly(para-aminobenzoic acid) (P-pABA) film was deposited in a pABA solution by potentiodynamic cycling of potential with and without the template (melamine) on a glassy carbon electrode. The surface feature of the modified

Ya Ting Liu; Jian Deng; Xi Lin Xiao; Li Ding; Ya Li Yuan; Hui Li; Xiu Ting Li; Xiao Na Yan; Li Li Wang

2011-01-01

381

para Nitrophenol 4-monooxygenase and hydroxyquinol 1,2-dioxygenase catalyze sequential transformation of 4-nitrocatechol in Pseudomonas sp. strain WBC3  

Microsoft Academic Search

Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen and energy. PnpA (PNP 4-monooxygenase) and PnpB (para-benzoquinone reductase) were shown to be involved in the initial steps of PNP catabolism via hydroquinone. We demonstrated\\u000a here that PnpA also catalyzed monooxygenation of 4-nitrocatechol (4-NC) to hydroxyquinol, probably via hydroxyquinone. It\\u000a was the first time that a

Min Wei; Jun-Jie Zhang; Hong Liu; Ning-Yi Zhou

2010-01-01

382

The actinobacterial signature protein ParJ (SCO1662) regulates ParA polymerization and affects chromosome segregation and cell division during Streptomyces sporulation.  

PubMed

Bacterial chromosome segregation usually involves cytoskeletal ParA proteins, ATPases which can form dynamic filaments. In aerial hyphae of the mycelial bacterium Streptomyces coelicolor, ParA filaments extend over tens of microns and are responsible for segregation of dozens of chromosomes. We have identified a novel interaction partner of S. coelicolor ParA, ParJ. ParJ negatively regulates ParA polymerization in vitro and is important for efficient chromosome segregation in sporulating aerial hyphae. ParJ-EGFP formed foci along aerial hyphae even in the absence of ParA. ParJ, which is encoded by sco1662, turned out to be one of the five actinobacterial signature proteins, and another of the five is a ParJ paralogue. We hypothesize that polar growth, which is characteristic not only of streptomycetes, but even of simple Actinobacteria, may be interlinked with ParA polymer assembly and its specific regulation by ParJ. PMID:21143314

Ditkowski, Bartosz; Tro?, Paulina; Ginda, Katarzyna; Donczew, Magdalena; Chater, Keith F; Zakrzewska-Czerwi?ska, Jolanta; Jakimowicz, Dagmara

2010-12-01

383

Characterization of a Conserved Interaction between DNA Glycosylase and ParA in Mycobacterium smegmatis and M. tuberculosis  

PubMed Central

The chromosome partitioning proteins, ParAB, ensure accurate segregation of genetic materials into daughter cells and most bacterial species contain their homologs. However, little is known about the regulation of ParAB proteins. In this study, we found that 3-methyladenine DNA glycosylase I MsTAG(Ms5082) regulates bacterial growth and cell morphology by directly interacting with MsParA (Ms6939) and inhibiting its ATPase activity in Mycobacterium smegmatis. Using bacterial two-hybrid and pull-down techniques in combination with co-immunoprecipitation assays, we show that MsTAG physically interacts with MsParA both in vitro and in vivo. Expression of MsTAG under conditions of DNA damage induction exhibited similar inhibition of growth as the deletion of the parA gene in M. smegmatis. Further, the effect of MsTAG on mycobacterial growth was found to be independent of its DNA glycosylase activity, and to result instead from direct inhibition of the ATPase activity of MsParA. Co-expression of these two proteins could counteract the growth defect phenotypes observed in strains overexpressing MsTAG alone in response to DNA damage induction. Based on protein co-expression and fluorescent co-localization assays, MsParA and MsTAG were further found to co-localize in mycobacterial cells. In addition, the interaction between the DNA glycosylase and ParA, and the regulation of ParA by the glycosylase were conserved in M. tuberculosis and M. smegmatis. Our findings provide important new insights into the regulatory mechanism of cell growth and division in mycobacteria.

Huang, Feng; He, Zheng-Guo

2012-01-01

384

Collisional excitation of CN(X2?+) by para- and ortho-H2: Fine-structure resolved transitions.  

PubMed

We present a new four dimensional potential energy surface (PES) for the CN(X(2)?(+))-H2 system. Both molecules were treated as rigid rotors. Potential energy was obtained from the electronic structure calculations using a partially spin-restricted coupled cluster with single, double, and perturbative triple excitations method. The four atoms were described using the augmented correlation-consistent triple zeta (aug-cc-pVTZ) basis sets augmented with mid-bond functions for improved description of van der Waals interactions. The global minimum is characterized by the well depth of 121.36 cm(-1) for the linear CN???H2 structure. The zero-order corrected dissociation energies D0 are 27.73 cm(-1) and 38.75 cm(-1) for the complex with para- and ortho-H2, respectively. These theoretical results obtained using our new PES are in excellent agreement with experimental values [Y. Chen and M. C. Heaven, J. Chem. Phys. 109, 5171 (1998)]. We perform fully quantum close coupling calculations of the rotationally inelastic cross sections of CN in collisions with para-H2 and ortho-H2 at low and intermediate energies. Corresponding rate coefficients were compared with experimental results of Brunet et al. [J. Chem. Phys. 116, 3617 (2002)]. A good agreement between theoretical and experimental results was found. Fine-structure resolved cross sections were then obtained through a recoupling technique. Significant differences exist between para- and ortho-H2 results. The propensity rules between fine-structure levels are also studied, and it is shown that the cross sections for ?j = ?N transitions are much larger than those for ?j ? ?N transitions, as expected from theoretical considerations. PMID:23968086

Kalugina, Yulia; K?os, Jacek; Lique, François

2013-08-21

385

Collisional excitation of CN(X2?+) by para- and ortho-H2: Fine-structure resolved transitions  

NASA Astrophysics Data System (ADS)

We present a new four dimensional potential energy surface (PES) for the CN(X2?+)-H2 system. Both molecules were treated as rigid rotors. Potential energy was obtained from the electronic structure calculations using a partially spin-restricted coupled cluster with single, double, and perturbative triple excitations method. The four atoms were described using the augmented correlation-consistent triple zeta (aug-cc-pVTZ) basis sets augmented with mid-bond functions for improved description of van der Waals interactions. The global minimum is characterized by the well depth of 121.36 cm-1 for the linear CN...H2 structure. The zero-order corrected dissociation energies D0 are 27.73 cm-1 and 38.75 cm-1 for the complex with para- and ortho-H2, respectively. These theoretical results obtained using our new PES are in excellent agreement with experimental values [Y. Chen and M. C. Heaven, J. Chem. Phys. 109, 5171 (1998)]. We perform fully quantum close coupling calculations of the rotationally inelastic cross sections of CN in collisions with para-H2 and ortho-H2 at low and intermediate energies. Corresponding rate coefficients were compared with experimental results of Brunet et al. [J. Chem. Phys. 116, 3617 (2002)]. A good agreement between theoretical and experimental results was found. Fine-structure resolved cross sections were then obtained through a recoupling technique. Significant differences exist between para- and ortho-H2 results. The propensity rules between fine-structure levels are also studied, and it is shown that the cross sections for ?j = ?N transitions are much larger than those for ?j ? ?N transitions, as expected from theoretical considerations.

Kalugina, Yulia; K?os, Jacek; Lique, François

2013-08-01

386

Domain 2 of Drosophila para voltage-gated sodium channel confers insect properties to a rat brain channel.  

PubMed

The ability of the excitatory anti-insect-selective scorpion toxin AahIT (Androctonus australis hector) to exclusively bind to and modify the insect voltage-gated sodium channel (NaCh) makes it a unique tool to unravel the structural differences between mammalian and insect channels, a prerequisite in the design of selective pesticides. To localize the insect NaCh domain that binds AahIT, we constructed a chimeric channel composed of rat brain NaCh alpha-subunit (rBIIA) in which domain-2 (D2) was replaced by that of Drosophila Para (paralytic temperature-sensitive). The choice of D2 was dictated by the similarity between AahIT and scorpion beta-toxins pertaining to both their binding and action and the essential role of D2 in the beta-toxins binding site on mammalian channels. Expression of the chimera rBIIA-ParaD2 in Xenopus oocytes gave rise to voltage-gated and TTX-sensitive NaChs that, like rBIIA, were sensitive to scorpion alpha-toxins and regulated by the auxiliary subunit beta(1) but not by the insect TipE. Notably, like Drosophila Para/TipE, but unlike rBIIA/beta(1), the chimera gained sensitivity to AahIT, indicating that the phyletic selectivity of AahIT is conferred by the insect NaCh D2. Furthermore, the chimera acquired additional insect channel properties; its activation was shifted to more positive potentials, and the effect of alpha-toxins was potentiated. Our results highlight the key role of D2 in the selective recognition of anti-insect excitatory toxins and in the modulation of NaCh gating. We also provide a methodological approach to the study of ion channels that are difficult to express in model expression systems. PMID:12040042

Shichor, Iris; Zlotkin, Eliahu; Ilan, Nitza; Chikashvili, Dodo; Stuhmer, Walter; Gordon, Dalia; Lotan, Ilana

2002-06-01

387

Radiosurgery for Para-IAC Meningiomas: The Effect of Radiation Dose to the Cochlea on Hearing Outcome  

SciTech Connect

Purpose: This study was performed to assess the radiosurgical results of meningiomas extending into the internal acoustic canal (para-IAC meningiomas), with a particular focus on the effect of radiation dose to the cochlea on hearing outcome. Methods and Materials: A total of 50 patients who underwent radiosurgery for para-IAC meningiomas between 1998 and 2009, which were followed for 2 years, were enrolled. The mean age was 55.8 years (range, 15-75). The mean tumor volume was 6.1 cm{sup 3} (range, 1.0-19.0), the mean tumor length in the IAC was 6.9 mm (range, 1.3-13.3), and the mean prescribed marginal dose was 13.1 Gy (range, 10-15) at an isodose line of 50%. The mean follow-up duration was 46 months (range, 24-122). Results: Eight (16.0%) patients had nonserviceable hearing at the time of surgery. At the last follow-up, the tumor control rate was 94%; unchanged in 17 patients, decreased in 30 patients, and increased in 3 patients. Among 42 patients with serviceable hearing at the time of radiosurgery, it was preserved in 41 (97.6%) patients at the last follow-up. The maximal and mean radiation doses to the cochleae of these 41 patients were 5.8 Gy {+-} 0.3 (range, 3.1-11.5) and 4.3 Gy {+-} 0.2 (range, 2.2-7.5), respectively. The maximal dose to the cochlea of the patient who lost hearing after radiosurgery was 4.7 Gy. Conclusions: The radiation dose to the cochlea may have the minimal toxic effect on the hearing outcome in patients who undergo radiosurgery for para-IAC meningiomas.

Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Paek, Sun Ha; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2012-11-01

388

Theoretical Study of the Mechanism Behind the para-Selective Nitration of Toluene in Zeolite H-Beta  

SciTech Connect

In this work, we investigate the origin of the favorable para-selective nitration of toluene exhibited by H- beta zeolite solid acid catalyst. Periodic density functional theory calculations were performed to study the toluene nitration by acetyl nitrate within the pore system of a model H-beta structure. Firstly, energetics were calculated for each of the 32 crystallographically unique Br¿nsted acid sites of a beta polymorph B zeolite unit cell. These calculations revealed more than one favorable Br¿nsted acid site. However, steric and mechanistic considerations could be used to argue that one particular aluminum site with three favorable Br¿nsted site oxygens comprising a 12-T pore wall would be a likely site for nitration to take place. Transition state searches around this aluminum site were performed to determine the barrier to reaction for both para and ortho nitration of the toluene. A three-step process was assumed for the nitration of toluene with two organic intermediates: the ¼-complex and the ¾-complex (i.e., Wheland or arenium complex). The rate limiting step of the three-step process is the transfer of the proton from the ¾-complex to a Br¿nsted site on the zeolite cage. The barrier for this step in the ortho nitration case is shown to be nearly 2.5 times that for the para nitration case. The reason for the discrepancy appears to be a subtle steric constraint imposed by the curvature of the 12-T pore system of the beta zeolite and the methyl group of the toluene in the case of the ortho approach.

Andersen, Amity; Govind, Niri; Subramanian, Lalitha

2008-10-24

389

On the contribution of non-additive three-body interactions to the third virial coefficient of para-hydrogen  

NASA Astrophysics Data System (ADS)

We use a path-integral Monte Carlo method together with state-of-the-art pair and three-body potentials to calculate the third virial coefficient C(T) of para-hydrogen in the temperature range 30-2000 K. Our results point out that non-additive three-body interactions have a sizable effect in determining the value of C(T) for T < 200 K. Although a good agreement with experimental data is obtained, the accuracy of the calculations is limited by the incomplete knowledge of the three-body potential energy surface.

Garberoglio, Giovanni

2013-02-01

390

Community P references for the A llocation & D onation of O rgans - The PAraDOx Study  

Microsoft Academic Search

Background  Transplantation is the treatment of choice for people with severe organ failure. However, demand substantially exceeds supply\\u000a of suitable organs; consequently many people wait months, or years to receive an organ. Reasons for the chronic shortage of\\u000a deceased organ donations are unclear; there appears to be no lack of 'in principle' public support for organ donation.\\u000a \\u000a \\u000a \\u000a \\u000a Methods\\/Design  The PAraDOx Study examines

Kirsten Howard; Stephen Jan; John Rose; Steven Chadban; Richard DM Allen; Michelle Irving; Allison Tong; Germaine Wong; Jonathan C Craig; Alan Cass

2011-01-01

391

Upper limit for the D2H+ ortho-to-para ratio in the prestellar core 16293E (CHESS)  

NASA Astrophysics Data System (ADS)

The H_3^+ ion plays a key role in the chemistry of dense interstellar gas clouds where stars and planets are forming. The low temperatures and high extinctions of such clouds make direct observations of H_3^+ impossible, but lead to large abundances of H2D+ and D2H+, which are very useful probes of the early stages of star and planet formation. The ground-state rotational ortho-D2H+ 11,1-00,0 transition at 1476.6 GHz in the prestellar core 16293E has been searched for with the Herschel HIFI instrument, within the CHESS (Chemical HErschel Surveys of Star forming regions) Key Program. The line has not been detected at the 21 mK km s-1 level (3? integrated line intensity). We used the ortho-H2D+ 11,0-11,1 transition and para-D2H+ 11,0-10,1 transition detected in this source to determine an upper limit on the ortho-to-para D2H+ ratio as well as the para-D2H+/ortho-H2D+ ratio from a non-local thermodynamic equilibrium analysis. The comparison between our chemical modeling and the observations suggests that the CO depletion must be high (larger than 100), with a density between 5 × 105 and 106 cm-3. Also the upper limit on the ortho-D2H+ line is consistent with a low gas temperature (~11 K) with a ortho-to-para ratio of 6 to 9, i.e. 2 to 3 times higher than the value estimated from the chemical modeling, making it impossible to detect this high frequency transition with the present state of the art receivers. The chemical network is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/547/A33Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Vastel, C.; Caselli, P.; Ceccarelli, C.; Bacmann, A.; Lis, D. C.; Caux, E.; Codella, C.; Beckwith, J. A.; Ridley, T.

2012-11-01

392

The synthesis and biological evaluation of para-substituted phenolic N-alkyl carbamates as endocannabinoid hydrolyzing enzyme inhibitors  

Microsoft Academic Search

A series of para-substituted phenolic N-alkyl carbamates were evaluated for their FAAH and MGL inhibitory activities. The compounds were generally selective for FAAH, with IC50 values in the nM range, whereas inhibition of MGL required concentrations three orders of magnitude higher. The most potent compounds, dodecylcarbamic acid 4-(4,5-dihydrothiazol-2-yl)phenyl (12) and 4-(1,2,3-thiadiazol-4-yl)phenyl (26) esters, inhibited FAAH and MGL with IC50 values

Anna Minkkilä; Mikko J. Myllymäki; Susanna M. Saario; Joel A. Castillo-Melendez; Ari M. P. Koskinen; Christopher J. Fowler; Jukka Leppänen; Tapio Nevalainen

2009-01-01

393

Effects of Rotational-Symmetry Breaking on Physisorption of Ortho- and Para-H2 on Ag(111)  

NASA Astrophysics Data System (ADS)

Quantum-state-selective thermal desorption of H2 weakly physisorbed on Ag(111) demonstrates significantly different desorption features between the nuclear-spin modifications. An energy shift due to the rotational-symmetry breaking induced by an anisotropic interaction affects not only the enthalpy but also the entropy of adsorption. The preexponential factor for desorption of the ortho-H2 is about three times as large as that of the para-H2. The entropy difference indicates a perpendicular orientation preference of anisotropic physisorption potential, which also suggests the importance of partial hybridization interaction for weak physisorption.

Sugimoto, Toshiki; Fukutani, Katsuyuki

2014-04-01

394

Effects of rotational-symmetry breaking on physisorption of ortho- and para-H2 on Ag(111).  

PubMed

Quantum-state-selective thermal desorption of H2 weakly physisorbed on Ag(111) demonstrates significantly different desorption features between the nuclear-spin modifications. An energy shift due to the rotational-symmetry breaking induced by an anisotropic interaction affects not only the enthalpy but also the entropy of adsorption. The preexponential factor for desorption of the ortho-H2 is about three times as large as that of the para-H2. The entropy difference indicates a perpendicular orientation preference of anisotropic physisorption potential, which also suggests the importance of partial hybridization interaction for weak physisorption. PMID:24765990

Sugimoto, Toshiki; Fukutani, Katsuyuki

2014-04-11

395

A comparative study of the clearance of respirable para-aramid, chrysotile and glass fibres from rat lungs.  

PubMed

A number of studies have indicated that the relative toxicity of different fibre types after inhalation is related to their durability within lung tissue. The aim of this study was to assess the relative biopersistence of respirable para-aramid fibrils, chrysotile asbestos and code 100/475 glass fibres in rat lungs. The biopersistence of all three test fibres was measured by quantifying the changes in retained lung burden through time following 10 days inhalation exposure to the same target concentration (700 fibres ml-1) for each fibre type. The lung burden analyses for all three fibre types show large reductions in number and volume of retained fibres during the 16 months following exposure. Most of this reduction in lung fibre burden occurred during the first 3 months following exposure but the pattern of clearance of different size classes varies with fibre type. The para-aramid data show rapid clearance of the longest fibrils during the first months following exposure, combined with an initial increase in the numbers of shorter fibrils. This is consistent with the disintegration of para-aramid fibrils into shorter fragments that subsequently are more readily cleared by macrophages. The code 100/475 glass fibre data also show rapid clearance of the longer fibres combined with an increase in the numbers of very short fibres, consistent with the removal of long fibres through disintegration. In contrast, the chrysotile data show a more rapid reduction in the numbers of retained short fibres than of long fibres, which is consistent with preferential clearance of short fibres by macrophages and minimal transverse breakage of fibres. The biopersistence of all three fibre types, in terms of overall percentage of fibres retained after 16 months is similar, but the durability of long (> 15 microns) chrysotile fibres is very much greater than that of long fibres of code 100/475 glass or para-aramid. The clearance of the three fibre types cannot be adequately described by the first order kinetic model that is often applied in studies of lung clearance. The apparent half time of clearance of each of the fibre types depends on the size fraction and time interval examined. PMID:9155241

Searl, A

1997-04-01

396

Theoretical study in gas phase of linear and nonlinear optical properties of the ortho- , meta- and para- nitrophenol isomers  

Microsoft Academic Search

The linear (?), and nonlinear (?,\\u000a ?) optical NLO properties of ortho-, meta- and para-nitrophenol (ONP, MNP and PNP) isomers have been calculated in gas phase by using ab initio (HF, MP2 and MP4) and density\\u000a functional theory (DFT) (B3LYP, CAM-B3LYP) methods, with the 6-31+G(d,p) and 6-311+G(3d,3p) standard and the Sadlej specialized\\u000a basis sets. These properties were evaluated both at static

Johan Urdaneta; Yaneth Bermúdez; Federico Arrieta; Merlin Rosales; Néstor Cubillán; Javier Hernández; Olga Castellano; Humberto Soscún

2010-01-01

397

Simple ortho- and para-hydroquinones as compounds neuroprotective against oxidative stress in a manner associated with specific transcriptional activation  

SciTech Connect

Electrophilic compounds protect neurons through the activation of the Keap1/Nrf2 pathway and the induction of phase-2 enzymes [T. Satoh, S.A. Lipton, Redox regulation of neuronal survival by electrophilic compounds, Trends Neurosci. 30 (2007) 38-45; T. Satoh, S. Okamoto, J. Cui, Y. Watanabe, K. Furuta, M. Suzuki, K. Tohyama, S.A. Lipton, Activation of the Keap1/Nrf2 pathway for neuroprotection by electrophilic phase II inducers. Proc. Natl. Acad. Sci. USA 103 (2006) 768-773]. Hydroquinone-type electrophilic compounds such as tert-butyl hydroquinone (TBHQ) and carnosic acid (CA) have attracted special attention, because the oxidative conversion of 'hydroquinone' to 'quinone' is essential for the transcriptional activation of the above-mentioned enzymes [T. Satoh, K. Kosaka, K. Itoh, A. Kobayashi, M. Yamamoto, Y. Shimojo, C. Kitajima, J. Cui, J. Kamins, S. Okamoto, T. Shirasawa, S.A. Lipton, Carnosic acid, a catechol-type electrophilic compound, protect neurons both in vitro and in vivo through activation of the Keap1/Nrf2 pathway via S-alkylation of specific cysteine, J. Neurochem. 104 (2008) 1161-1131; A.D. Kraft, D.A. Johnson, J.A. Johnson, Nuclear factor E2-related factor 2-dependent antioxidant response element activation by tert-butylhydroquinone and sulforaphane occurring preferentially in astrocytes conditions neurons against oxidative insult, J. Neurosci. 24 (2004) 1101-1112]. In the present study, we examined the relationship between electrophilicity and the protective effects afforded by electrophilic compounds. Electrophilicity was assessed in terms of the ability of a compound to bind to a cysteine on bovine serum albumin, by which we found that neuroprotective hydroquinones [TBHQ (para-) and CA (ortho-)] had distinctive patterns of cysteine binding compared with other electrophilic compounds. Further, we found that isomers of simple ortho- and para-hydroquinones such as 2-methylhydroquinone (para-) and 4-methyl-catechol (ortho-) [not in abstract] had similar properties of cysteine binding as TBHQ and CA, which compounds were associated with the transcriptional activation and an increase in the level of reduced glutathione. These results suggest that para- and ortho-dihydroquinones may be neuroprotective compounds active against oxidative stress.

Satoh, Takumi [Department of Welfare Engineering, Faculty of Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate 020-8551 (Japan)], E-mail: tsatoh@iwate-u.ac.jp; Saitoh, Sachie; Hosaka, Manami [Department of Welfare Engineering, Faculty of Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate 020-8551 (Japan); Kosaka, Kunio [Research and Development Center, Nagase Co., Ltd., Kobe, Hyogo 651-2241 (Japan)

2009-02-06

398

Identification of a point mutation in the para-type sodium channel gene from a pyrethroid-resistant cattle tick.  

PubMed

To investigate the molecular mechanism of resistance to pyrethroids in the southern cattle tick, Boophilus microplus, we have obtained and sequenced a partial para-homologous sodium channel cDNA from susceptible and pyrethroid-resistant tick strains. A point mutation that results in an amino acid change from Phe to Ile was identified in the highly conserved domain IIIS6 of the homologous sodium channel from ticks that are highly resistant to pyrethroid acaricides. This mutation is at a location different from those reported in the same gene in pyrethroid-resistant insects. PMID:10441465

He, H; Chen, A C; Davey, R B; Ivie, G W; George, J E

1999-08-11

399

Numerical prediction of wall temperatures for near-critical para-hydrogen in turbulent upflow inside vertical tubes  

NASA Technical Reports Server (NTRS)

Presented herein is a method of including density fluctuations in the equations of turbulent transport. Results of a numerical analysis indicate that the method may be used to predict heat transfer for the case of near-critical para-hydrogen in turbulent upflow inside vertical tubes. Wall temperatures, heat transfer coefficients, and velocities obtained by coupling the equations of turbulent momentum and heat transfer with a perturbed equation of state show good agreement with experiment for inlet reduced pressures of 1.28-5.83.

Bellmore, C. P.; Reid, R. L.

1980-01-01

400

Growth, structural, spectroscopic and optical studies of pure and amino acid (glycine) doped methyl-para-hydroxy benzoate single crystals  

NASA Astrophysics Data System (ADS)

Methyl-para-hydroxy benzoate is a potential organic nonlinear optical (NLO) material. The pure and amino acid (glycine) doped MHB crystals are grown by slow evaporation solution growth technique. Single crystal X-ray diffraction studies of both pure and amino acid doped samples are carried out and the results are compared. FTIR studies are performed to identify the presence of various functional groups in the grown crystal. The UV-vis spectra confirm the improvement in the transparency of these crystals on doping amino acid. The amino acid doping improves the NLO properties. The dopant increases the hardness value of the material.

Selvaraju, K.; Kirubavathi, K.; Kumararaman, S.

2009-05-01

401

Materiales compuestos de matriz met´ alica rica en Zn con alto contenido de Al y componente estructural de ZnO  

Microsoft Academic Search

22 %wt Al alloy, and powders quantities of ZnO that were 0.0 %, 0.01 %, 0.1 %, 1 % y 10 % of the total weight of each mix. The mixes were after compacted with a load of 16 tons and acetone as lubricant. The sintering was made in steps of 15 minutes of duration at 357-C. Be- fore each

J. A. Arag; J. R. Mirandab

402

Para-derivatized pybox ligands as sensitizers in highly luminescent Ln(III) complexes.  

PubMed

New complexes of pyridine-bis(oxazoline) derivatized with -H, -OMe, and -Br at the para position of the pyridine ring with Eu(III) and Tb(III) have been isolated. These are highly luminescent in the solid state, regardless of the ligand-to-metal ratio. Several of the metal complexes were isolated and characterized by single crystal X-ray diffraction, showing the rich diversity of structures that can be obtained with this family of ligands. [Eu(PyboxOMe)(3)](NO(3))(3)·3CH(2)Cl(2), 1, crystallizes in the monoclinic space group P2(1)/n and has the cell parameters a = 14.3699(10) Å, b = 13.4059(9) Å, c = 25.8766(18) Å, ? = 95.367(1)°, and V = 4963.1(6) Å(3). The isostructural [Tb(PyboxOMe)(3)](NO(3))(3)·3CH(2)Cl(2), 2, crystallizes with the parameters a = 14.4845(16) Å, b = 13.2998(15) Å, c = 25.890(3) Å, ? = 94.918(2)°, and V = 4969.1(10) Å(3). 3, a 1:1 complex with the formula [Eu(PyboxBr)(NO(3))(3)(H(2)O)], crystallizes in the monoclinic P2(1)/c space group with a = 11.649(2) Å, b = 8.3914(17) Å, c = 20.320(4) Å, ? = 100.25(3)°, and V = 1954.5(7) Å(3). 4, a product of the reaction of PyboxBr with Tb(NO(3))(3), is [Tb(PyboxBr)(2)(?(2)-NO(3))(?(1)-NO(3)](2)[Tb(NO(3))(5)]·5H(2)O. It crystallizes in the monoclinic space group P2(1) with a = 15.612(3) Å, b = 14.330(3) Å, c = 16.271(3) Å, ? = 92.58(3)°, and V = 3636.5(13) Å(3). [Tb(Pybox)(3)](CF(3)SO(3))(3)·3CH(2)CN, 5, crystallizes in the triclinic space group P1? with a = 12.3478(2) Å, b = 15.0017(2) Å, c = 16.1476(4) Å, ? = 100.252(1)°, ? = 100.943(1)°, ? = 113.049(1)°, and V = 2594.80(8) Å(3). Finally, compound 6, [Tb(Pybox)(2)(NO(3))(H(2)O)](NO(3))(2)·CH(3)OH, crystallizes in the triclinic P1? space group with a = 9.7791(2) Å, b = 10.1722(2) Å, c = 15.3368(3) Å, ? = 83.753(1)°, ? = 78.307(1)°, ? = 85.630(1)°, and V = 1482.33(5) Å(3). In solution, the existence of 3:1, 2:1, and 1:1 species can be observed through absorption and luminescence speciation measurements as well as NMR spectroscopy. The stability constants in acetonitrile, as an average obtained from absorption and emission titrations, are log ?(11) = 5.4, log ?(12) = 8.8, and log ?(13) = 12.8 with Eu(III) and log ?(11) = 4.5, log ?(12) = 8.4, and log ?(13) = 11.7 for the Tb(III) species with PyboxOMe. Pybox displayed stability constants log ?(11) = 3.6, log ?(12) = 9.1, and log ?(13) = 12.0 with Eu(III) and log ?(11) = 3.7, log ?(12) = 9.3, and log ?(13) = 12.2 for the Tb(III) species. Finally, PyboxBr yielded log ?(11) = 7.1, log ?(12) = 12.2, and log ?(13) = 15.5 for the Eu(III) species and log ?(11) = 6.2, log ?(12) = 11.0, and log ?(13) = 15.4 with Tb(III). Photophysical characterization was performed in all cases on solutions with 3:1 ligand-to-metal ion stoichiometry and allowed determination of quantum yields and lifetimes of emission for PyboxOMe of 23.5 ± 1.6% and 1.54 ± 0.04 ms for Eu(III) and 21.4 ± 3.6% and 1.88 ± 0.04 ms for Tb(III). For Pybox these values were 25.6 ± 1.1% and 1.49 ± 0.04 ms for Eu(III) and 23.2 ± 2.1% and 0.44 ± 0.01 ms for Tb(III) and for PyboxBr they were 35.8 ± 1.6% and 1.46 ± 0.03 ms for Eu(III) and 23.3 ± 1.3% and a double lifetime of 0.79 ± 0.05/0.07 ± 0.01 ms for Tb(III). A linear relationship between the triplet level energies and the Hammett ? constants was found. Lifetime measurements in methanol as well as the NMR data in both methanol and acetonitrile indicate that all complexes are stable in the 3:1 stoichiometry in solution and that there is no solvent coordination to the metal ion. PMID:20809608

de Bettencourt-Dias, Ana; Barber, Patrick S; Viswanathan, Subha; de Lill, Daniel T; Rollett, Alexandra; Ling, George; Altun, Sultan

2010-10-01

403

Conformation Specific Electronic and Infrared Spectroscopy of Isolated [2,2,2]-PARA-TRICYLCLOPHANE and its Monohydrated Cluster  

NASA Astrophysics Data System (ADS)

[2,2,2]-Para-tricyclophane (TCP) is a highly symmetric macrocycle containing three para-substituted phenyl rings linked by ethyl bridges. Therefore, TCP affords a unique opportunity to explore the coupling between three electronic chromophores isolated in supersonic expansion. Furthermore, the three phenyl rings create an electron rich macrocyclic cavity capable of forming a ?-hydrogen bond to a single water molecule. Resonant two-photon ionization and UV-UV hole-burning spectroscopy proved that the monomer population resides in a single conformer. Its vibronic spectrum shows unusual activity in the first 150 Cm-1 due to the close, intermingled set of three excited states. Resonant ion-dip infrared (RIDIR) spectroscopy was carried out in the alkyl and aromatic CH stretch regions to probe the conformations of the three ethyl linkages. Dispersed fluorescence spectra served to probe the electronic energy transfer between the three phenyl rings, which is rampant already at low energies. In the TCP-H2O complex, RIDIR spectroscopy is used to characterize the ? H-bonding of H2O in the TCP cavity.

Buchanan, Evan G.; Dean, Jacob C.; Marsh, Brett M.; Zwier, Timothy S.

2011-06-01

404

Malaria rapid diagnostic devices: performance characteristics of the ParaSight F device determined in a multisite field study.  

PubMed

Microscopic detection of parasites has been the reference standard for malaria diagnosis for decades. However, difficulty in maintaining required technical skills and infrastructure has spurred the development of several nonmicroscopic malaria rapid diagnostic devices based on the detection of malaria parasite antigen in whole blood. The ParaSight F test is one such device. It detects the presence of Plasmodium falciparum-specific histidine-rich protein 2 by using an antigen-capture immunochromatographic strip format. The present study was conducted at outpatient malaria clinics in Iquitos, Peru, and Maesod, Thailand. Duplicate, blinded, expert microscopy was employed as the reference standard for evaluating device performance. Of 2,988 eligible patients, microscopy showed that 547 (18%) had P. falciparum, 658 (22%) had P. vivax, 2 (0.07%) had P. malariae, and 1,750 (59%) were negative for Plasmodium. Mixed infections (P. falciparum and P. vivax) were identified in 31 patients (1%). The overall sensitivity of ParaSight F for P. falciparum was 95%. When stratified by magnitude of parasitemia (no. of asexual parasites per microliter of whole blood), sensitivities were 83% (>0 to 500 parasites/microl), 87% (501 to 1,000/microl), 98% (1,001 to 5,000/microl), and 98% (>5,000/microl). Device specificity was 86%. PMID:11474008

Forney, J R; Magill, A J; Wongsrichanalai, C; Sirichaisinthop, J; Bautista, C T; Heppner, D G; Miller, R S; Ockenhouse, C F; Gubanov, A; Shafer, R; DeWitt, C C; Quino-Ascurra, H A; Kester, K E; Kain, K C; Walsh, D S; Ballou, W R; Gasser, R A

2001-08-01

405

Herschel observations of ortho- and para-oxidaniumyl (H2O+) in spiral arm clouds toward Sagittarius B2(M)  

NASA Astrophysics Data System (ADS)

H2O+ has been observed in its ortho- and para- states toward the massive star forming core Sgr B2(M), located close to the Galactic center. The observations show absorption in all spiral arm clouds between the Sun and Sgr B2. The average o/p ratio of H2O+ in most velocity intervals is 4.8, which corresponds to a nuclear spin temperature of 21 K. The relationship of this spin temperature to the formation temperature and current physical temperature of the gas hosting H2O+ is discussed, but no firm conclusion is reached. In the velocity interval 0-60 km s-1, an ortho/para ratio of below unity is found, but if this is due to an artifact of contamination by other species or real is not clear. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Appendix (pages 6, 7) is only available in electronic form at http://www.aanda.org

Schilke, P.; Comito, C.; Müller, H. S. P.; Bergin, E. A.; Herbst, E.; Lis, D. C.; Neufeld, D. A.; Phillips, T. G.; Bell, T. A.; Blake, G. A.; Cabrit, S.; Caux, E.; Ceccarelli, C.; Cernicharo, J.; Crockett, N. R.; Daniel, F.; Dubernet, M.-L.; Emprechtinger, M.; Encrenaz, P.; Falgarone, E.; Gerin, M.; Giesen, T. F.; Goicoechea, J. R.; Goldsmith, P. F.; Gupta, H.; Joblin, C.; Johnstone, D.; Langer, W. D.; Latter, W. B.; Lord, S. D.; Maret, S.; Martin, P. G.; Melnick, G. J.; Menten, K. M.; Morris, P.; Murphy, J. A.; Ossenkopf, V.; Pagani, L.; Pearson, J. C.; Pérault, M.; Plume, R.; Qin, S.-L.; Salez, M.; Schlemmer, S.; Stutzki, J.; Trappe, N.; van der Tak, F. F. S.; Vastel, C.; Wang, S.; Yorke, H. W.; Yu, S.; Erickson, N.; Maiwald, F. W.; Kooi, J.; Karpov, A.; Zmuidzinas, J.; Boogert, A.; Schieder, R.; Zaal, P.

2010-10-01

406

Development of a Highly Biocompatible Antituberculosis Nanodelivery Formulation Based on Para-Aminosalicylic Acid--Zinc Layered Hydroxide Nanocomposites  

PubMed Central

Tuberculosis is a lethal epidemic, difficult to control disease, claiming thousands of lives every year. We have developed a nanodelivery formulation based on para-aminosalicylic acid (PAS) and zinc layered hydroxide using zinc nitrate salt as a precursor. The developed formulation has a fourfold higher efficacy of PAS against mycobacterium tuberculosis with a minimum inhibitory concentration (MIC) found to be at 1.40??g/mL compared to the free drug PAS with a MIC of 5.0??g/mL. The newly developed formulation was also found active against Gram-positive bacteria, Gram-negative bacteria, and Candida albicans. The formulation was also found to be biocompatible with human normal lung cells MRC-5 and mouse fibroblast cells-3T3. The in vitro release of PAS from the formulation was found to be sustained in a human body simulated phosphate buffer saline (PBS) solution at pH values of 7.4 and 4.8. Most importantly the nanocomposite prepared using zinc nitrate salt was advantageous in terms of yield and free from toxic zinc oxide contamination and had higher biocompatibility compared to one prepared using a zinc oxide precursor. In summary, these promising in vitro results are highly encouraging for the continued investigation of para-aminosalicylic acid and zinc layered hydroxide nanocomposites in vivo and eventual preclinical studies.

Arulselvan, Palanisamy; El Zowalaty, Mohamed Ezzat; Fakurazi, Sharida; Webster, Thomas J.; Geilich, Benjamin; Hussein, Mohd Zobir

2014-01-01

407

High resolution quantum cascade laser studies of the ?3 band of methyl fluoride in solid para-hydrogen.  

PubMed

Spectra of solid para-H(2) doped with CH(3)F at 1.8 K are studied in the ?(3) region (~1040 cm(-1)) using a quantum cascade laser source. As shown previously, residual ortho-H(2) in the sample (~1000 ppm) gives rise to distinct spectral features due to clusters of the form CH(3)F-(ortho-H(2))(N), with N = 0, 1, 2, 3, etc. Brief annealing at 7 K is found to give narrower spectral lines (?0.006 cm(-1)) than conventional (5 K) annealing, and causes the N = 3 and 4 lines to fragment into two or more components. The N = 3 line is observed to be particularly stable and persistent. The N = 0 line (no ortho-H(2) neighbors) is resolved into two closely spaced (?0.007 cm(-1)) components which are assigned to the K = 0 and 1 states of CH(3)F rotating around its C(3v) symmetry axis (ortho- and para-CH(3)F, respectively). Similar K-structure is also evident for other lines. Weak but persistent features ("N = 1/2 lines") are observed mid way between N = 0 and 1. PMID:21974539

McKellar, A R W; Mizoguchi, Asao; Kanamori, Hideto

2011-09-28

408

A new ab initio potential energy surface for the collisional excitation of HCN by para- and ortho-H2  

NASA Astrophysics Data System (ADS)

We present a new four-dimensional potential energy surface for the collisional excitation of HCN by H2. Ab initio calculations of the HCN-H2 van der Waals complex, considering both molecules as rigid rotors, were carried out at the explicitly correlated coupled cluster with single, double, and perturbative triple excitations [CCSD(T)-F12a] level of theory using an augmented correlation-consistent triple zeta (aVTZ) basis set. The equilibrium structure is linear HCN-H2 with the nitrogen pointing towards H2 at an intermolecular separation of 7.20 a0. The corresponding well depth is -195.20 cm-1. A secondary minimum of -183.59 cm-1 was found for a T-shape configuration with the H of HCN pointing to the center of mass of H2. We also determine the rovibrational energy levels of the HCN-para-H2 and HCN-ortho-H2 complexes. The calculated dissociation energies for the para and ortho complexes are 37.79 cm-1 and 60.26 cm-1, respectively. The calculated ro-vibrational transitions in the HCN-H2 complex are found to agree by more than 0.5% with the available experimental data, confirming the accuracy of the potential energy surface.

Denis-Alpizar, Otoniel; Kalugina, Yulia; Stoecklin, Thierry; Vera, Mario Hernández; Lique, François

2013-12-01

409

Soj (ParA) DNA binding is mediated by conserved arginines and is essential for plasmid segregation  

PubMed Central

Soj is a member of the ParA family of ATPases involved in plasmid and chromosomal segregation. It binds nonspecifically and cooperatively to DNA although the function of this binding is unknown. Here, we show that mutation of conserved arginine residues that map to the surface of Bacillus subtilis Soj caused only minimal effects on nucleotide-dependent dimerization but had dramatic effects on DNA binding. Using a model plasmid partitioning system in Escherichia coli, we find that Soj DNA-binding mutants are deficient in plasmid segregation. The location of the arginines on the Soj structure explains why DNA binding depends on dimerization and was used to orient the Soj dimer on the DNA, revealing the axis of Soj polymerization. The arginine residues are conserved among other chromosomal homologues, including the ParAs from Caulobacter crescentus, Pseudomonas aeruginosa, Pseudomonas putida, Streptomyces coelicolor, and chromosome I of Vibrio cholerae indicating that DNA binding is a common feature of members of this family.

Hester, Christina M.; Lutkenhaus, Joe

2007-01-01

410

Effective conjugation and Raman intensities in oligo(para-phenylene)s: A microscopic view from first-principles calculations  

NASA Astrophysics Data System (ADS)

Electron-phonon coupling in oligo(para-phenylene)s is addressed in terms of the off-resonance Raman intensities of two distinct modes at 1220 and 1280 cm-1. On the basis of Albrecht's theory, vibrational coupling and Raman intensities are calculated from first-principles quantum-chemical methods. A few-state model is used to evaluate the dependence of the mode intensities on oligomer length, planarity, and excitation wavelength. The link between electron delocalization/conjugation and Raman intensities is highlighted. Extending on prior studies, the present work focuses on providing an in-depth understanding of the origin of this correlation in addition to reproducing experimental findings. The model applied here allows us to interpret the results on a microscopic, quantum-mechanical basis and to relate the observed trends to the molecular orbital structure and nature of the excited states in this class of materials. We find quantitative agreement between the results of the calculations and those of measurements performed on oligo(para-phenylene)s of various chain lengths in the solid state and in solution.

Heimel, Georg; Somitsch, Dieter; Knoll, Peter; Brédas, Jean-Luc; Zojer, Egbert

2005-03-01

411

Infrared Space Observatory Observations of Molecular Hydrogen in HH 54: Measurement of a Nonequilibrium Ratio of Ortho- to Para-H2  

NASA Technical Reports Server (NTRS)

We have detected the S(1), S(2), S(3), S(4), and S(5) pure rotational lines of molecular hydrogen toward the outflow source HH 54 using the Short Wavelength Spectrometer on board the Infrared Space Observatory. The observed H2 line ratios indicate the presence of warm molecular gas with an H2 density of at least 10(sup 5) /cc and a temperature approximately 650 K in which the ratio of ortho- to para-H2 is only 1.2 -+ 0.4, significantly smaller than the equilibrium ratio of 3 expected in gas at that temperature. These observations imply that the measured ratio of ortho- to para-H2 is the legacy of an earlier stage in the thermal history of the gas when the gas had reached equilibrium at a temperature approximately 90 K. Based upon the expected timescale for equilibration, we argue that the nonequilibrium ratio of ortho- to para-H2 observed in HH 54 serves as a chronometer that places a conservative upper limit of approximately 5000 yr on the period for which the emitting gas has been warm. The S(2)/,S(l) and S(3)/S(1) H2 line ratios measured toward HH 54 are consistent with recent theoretical models of Timmermann for the conversion of para- to ortho-H2 behind slow, C-type shocks, but only if the preshock ratio of ortho- to para-H2 was approximately < 0.2.

Neufeld, David A.; Melnick, Gary J.; Harwit, Martin

1998-01-01

412

Para-split laminotomy: a rescue technique for split laminotomy approach in exploring intramedullary midline located pathologies.  

PubMed

Objective?Conventional posterior approaches, which may involve multilevel laminectomies and facetectomies, may lead to spinal deformities, instability, and subluxation. We developed the multilevel spinous process splitting and distraction laminotomy technique, which is an option for approaching midline intramedullary spinal pathologies with preservation of mechanically relevant bone and muscle structures. In some cases, midline splitting is not feasible or convenient because of anatomical differences of spinous processes and laminas. Our objective was to develop a minimally invasive rescue approach technique that makes it possible to remove intramedullary lesions but does not increase the risk of damage to the crucial posterior stabilizers of the spine. Methods?We used the para-split laminotomy technique for opening the spinal canal not in the midline but rather in the parasagittal plane. The technique can be combined with the basic split laminotomy technique. This novel technique was used in five adult patients with midline intramedullary pathologies of the cervical and cervicothoracic spine. Results?The operating field under the microscope was sufficient for tumor removal according to the keyhole concept. The approach used did not affect the extent of resection or neurologic outcome. The average number of split laminae was 6 (range: 3-10). Average follow-up was 18 months (range: 13-36 months). Histologic results were as follows: two ependymomas, two astrocytomas, and one primitive neuroectodermal tumor (PNET). To confirm the extension of resection, all patients underwent postoperative magnetic resonance imaging evaluations. The resections were complete in the cases of two ependymomas, subtotal in one astrocytoma, and partial in the other astrocytoma case and the PNET case. Computed tomography scans showed the extension of para-split approaches and the moderately disturbed bony structures. Instability was detected in none of the patients on the flexion-extension lateral radiographs during the follow-up period. Conclusion?The minimally invasive multilevel para-split laminotomy approach as a rescue technique for split laminotomy is a safe and effective surgical procedure, suitable for exploring different intramedullary pathologies located in the midline of the spinal canal. This modified surgical approach fulfills the requirements of other minimally invasive techniques and lowers the risk of damage to the crucial posterior stabilizers of the spine; furthermore, disintegration of the vertebral arches and facet joints is reduced. PMID:24163263

Padanyi, Csaba; Vajda, Janos; Banczerowski, Peter

2014-07-01

413

A detailed perceptive on the growth and characterization studies of para amino hippuric acid (PAHA) single crystals.  

PubMed

Single crystals of para amino hippuric acid (PAHA) were grown by slow evaporation technique. The spectral and its structural properties of the crystals were studied by FT-IR, micro-Raman and factor group analysis. The optical transparency in the UV-Visible regions was found to be good for non-linear optics (NLO) applications. Thermogravimetric analysis (TGA) and Differential Thermal Analysis (DTA) showed that the compound decomposes beyond 300°C. The dielectric behavior of the compound predicts low dielectric loss at high frequency applied whereas in the case of mechanical behavior of the specimen hardness increases with increasing applied load. After certain weight increase, hardness gets saturated in the region of ?110. Relative second harmonic efficiency of the compound is found to be 1.8 times greater than that of potassium di-phosphate reference. PMID:24873892

Sathesh Kumar, K; Srinivasan, P; Mahadevan Pillai, V P

2014-11-11

414

Repair of juxtarenal para-anastomotic aortic aneurysms after previous open repair with fenestrated and branched endovascular stent grafts.  

PubMed

Three patients with juxtarenal para-anastomotic aortic aneurysms after previous open abdominal aortic aneurysm repair were treated with custom-designed fenestrated and branched Zenith endovascular stent grafts. Six renal arteries and two superior mesenteric arteries were targeted for incorporation by graft fenestrations and branches. The fenestration/renal ostium interface was secured with balloon-expandable Genesis stents (n = 5) or Jostent stent grafts (n = 1). Completion angiography demonstrated no endoleaks and antegrade perfusion in all target vessels. During follow-up, one patient developed asymptomatic renal artery occlusion and underwent further endovascular intervention for type I distal endoleak. Computed tomography at 12 months demonstrated complete aneurysm exclusion in all patients with antegrade perfusion in the remaining target vessels. Fenestrated and branched endovascular stent grafts may be an acceptable alternative to conventional open repair in this group of patients. PMID:16275460

Adam, Donald J; Berce, Michael; Hartley, David E; Anderson, John L

2005-11-01

415

Communication: Quantum molecular dynamics simulation of liquid para-hydrogen by nuclear and electron wave packet approach  

NASA Astrophysics Data System (ADS)

Liquid para-hydrogen (p-H2) is a typical quantum liquid which exhibits strong nuclear quantum effects (NQEs) and thus anomalous static and dynamic properties. We propose a real-time simulation method of wave packet (WP) molecular dynamics (MD) based on non-empirical intra- and inter-molecular interactions of non-spherical hydrogen molecules, and apply it to condensed-phase p-H2. The NQEs, such as WP delocalization and zero-point energy, are taken into account without perturbative expansion of prepared model potential functions but with explicit interactions between nuclear and electron WPs. The developed MD simulation for 100 ps with 1200 hydrogen molecules is realized at feasible computational cost, by which basic experimental properties of p-H2 liquid such as radial distribution functions, self-diffusion coefficients, and shear viscosities are all well reproduced.

Hyeon-Deuk, Kim; Ando, Koji

2014-05-01

416

Improved Performance of Phthalocyanine Derivative Field-Effect Transistors by Inserting a Para-Quarterphenyl as the Inducing Layer  

NASA Astrophysics Data System (ADS)

We investigate the phthalocyanine derivative organic field-effect transistors (OFETs) using a novel para - quaterphenyl (p-4p) as the inducing layer. Compared to the devices without the p-4p inducing layer, the performances of p-type (copper phthalocyanine) and n-type (fluorinated copper phthalocyanine) OFETs with optimized thickness of p-4p thin films are greatly enhanced. Both the field-effect mobility and the on/off ratio of the two-type devices are improved by one order of magnitude compared to those of the control devices. This remarkable improvement is attributed to the introduction of p-4p, which can form a highly oriented and continuous phthalocyanine derivative film with the molecular ?–? stack direction parallel to the substrate.

Dong, Ni; Wu, Xiao-Ming; Dang, Huan-Qin; Liu, Dong-Yue; Zhang, Qiang; Wei, Jun; Yin, Shou-Gen

2014-05-01

417

Allergic dermatitis - Black henna (para-phenylenediamine) use among the East African patient population in a general practice setting.  

PubMed

The use of henna has become a global phenomenon for skin adornment in arms and legs. The practice is old and common among communities of East African origin. Traditionally, natural henna is used during Eid celebrations, marriage ceremonies and other social occasions. However, black henna type with para-phenylenediamine (PPD) additive is gaining favour over the natural one due to its effect and ease in achieving the desired intensity, longevity and ease of drying. The natural henna stains the skin orange to brown and takes an hour to dry while black henna is intensely black and dries in minutes. This article describes a case of allergic dermatitis due to a black henna use seen in a general practice clinic setting and highlights the role of education and counselling of a particular community. PMID:24897988

Berih, Abdullahi; Berhanu, Alamin

2014-06-01

418

Measurements of the H2(13)CO ortho/para ratio in cold dark molecular clouds  

NASA Technical Reports Server (NTRS)

H2(13)CO has been detected for the first time toward cold dark molecular clouds using the NRAO 12 m telescope. The H2(13)CO ortho/para abundance ratio R for B335, which we report as R approximately 1.7, suggests equilibrium at the local kinetic temperature and appears to be distinctly different from that for both TMC-1 and L134N, where R is close to or higher than the statistical value 3. Since only B335 among the observed positions includes an imbedded IR source, this difference may result from heating of the grain surfaces, providing the energy necessary for desorption of formaldehyde formed on the grains.

Minh, Y. C.; Dickens, J. E.; Irvine, W. M.; McGonagle, D.

1995-01-01

419

Cloning and functional analysis of TipE, a novel membrane protein that enhances Drosophila para sodium channel function.  

PubMed

Voltage-dependent sodium channels are involved in the initiation and propagation of action potentials in many excitable cells. Here we report that tipE, a gene defined by a temperature-sensitive paralytic mutation in Drosophila, encodes a novel integral membrane protein that dramatically stimulates functional expression in Xenopus oocytes of the Drosophila sodium channel alpha subunit encoded by the paralytic (para) locus. Using a heat shock promoter to control tipE+ gene expression in transgenic flies, we demonstrate that tipE+ gene expression is required during pupal development to rescue adult paralysis. In addition, we demonstrate a role for the tipE gene product in adults. PMID:7553842

Feng, G; Deák, P; Chopra, M; Hall, L M

1995-09-22

420

La Observaci?n Sistem?tica de Vecindarios: El caso de Chile y sus perspectivas para Trabajo Social  

PubMed Central

El estudio acerca de las características de los vecindarios y sus efectos sobre las personas ha llegado a ser un área de creciente atención por parte de investigadores de diversas disciplinas en países desarrollados. Aunque actualmente existen diversas metodologías para estudiar efectos del vecindario, una de las más utilizadas es la Observación Sistemática de Vecindarios –Systematic Social Observation SSO, en inglés—porque permite recolectar información acerca de diversas características del entorno físico, social, ambiental y económico de los vecindarios donde se aplica. El objetivo de este artículo es (i) dar a conocer sumariamente algunas investigaciones influyentes sobre efectos del vecindario en Estados Unidos, ii) describir cómo se diseñó e implementó la Observación Sistemática de Vecindarios en la ciudad de Santiago de Chile, iii) señalar algunos facilitadores y obstaculizadores de la implementación del proyecto y, finalmente iv) enunciar posibles contribuciones y limitaciones que esta metodología ofrecería al trabajo social en Chile.

Sanhueza, Guillermo E.; Delva, Jorge; Andrade, Fernando H.; Grogan-Kaylor, Andrew; Bares, Cristina; Castillo, Marcela

2012-01-01

421

Crystal structure determination from two-dimensional powders: A combined experimental and theoretical approach. The example para-cyano-quaterphenylene  

NASA Astrophysics Data System (ADS)

A combined experimental and theoretical approach is used to solve the unknown crystal structure of para-cyano-quaterphenylene. Thin films are prepared by physical vapor deposition on isotropic surfaces, whereby a two-dimensional powder is formed. Using specular and grazing incidence X-ray diffraction, the crystallographic unit cell of the dominant polymorph phase is obtained. A monoclinic lattice with unit cell parameters a=5.56 Å, b=7.67 Å, c=20.85 Å, and ?=97.4? is determined. These experimental parameters are used as input for ab initio calculations within the framework of density-functional theory to determine the molecular packing within the crystal structure. Three types of molecular arrangements are found, exhibiting very close energies of formation. From the comparison of calculated structure factors with the experimentally observed intensities two solutions could be excluded. The molecule is found to pack in a herringbone pattern with layers of upright standing molecules.

Moser, A.; Werzer, O.; Flesch, H.-G.; Koini, M.; Smilgies, D.-M.; Nabok, D.; Puschnig, P.; Ambrosch-Draxl, C.; Schiek, M.; Rubahn, H.-G.; Resel, R.

2009-02-01

422

para-Nitroaniline is a Promising Matrix for MALDI-MS Imaging on Intermediate Pressure MS Systems  

NASA Astrophysics Data System (ADS)

para-Nitroaniline (PNA) is presented as a promising matrix for matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) on an intermediate-pressure ion source (~1 Torr) QqTOF instrument using an Nd:YVO4 laser operated at 5 kHz. An imaging study was carried out to determine the utility of PNA at this pressure by analyzing 14 tissue sections. We demonstrate acquisition of high-quality imaging data over a 6-h period in the ion source. In this study, comparisons were made between PNA and ?-cyano-4-hydroxycinnamic acid (CHCA) in positive ion mode to demonstrate the utility of PNA in these circumstances. PNA performed as well as or better than CHCA in terms of lipid ion intensities, resulting in lower levels of ion fragmentation and in lower incidences of analyte migration at the edges of the tissue sections when using airspray matrix deposition.

Steven, Rory T.; Race, Alan M.; Bunch, Josephine

2013-05-01

423

Centroid path integral molecular-dynamics studies of a para-hydrogen slab containing a lithium impurity  

NASA Astrophysics Data System (ADS)

Six-layer para-hydrogen (p-H2) semi-infinite slabs, containing a Li impurity atom in different locations, have been investigated at 2.5-14.7 K by means of centroid path integral molecular-dynamics simulations. On the time scale of the simulations (15 ps), lithium atoms initially doped inside the slab appear to remain trapped in the lattice and show no tendency to diffuse toward the surface. The slab surface layers are observed to melt more readily than the inner ones, even when the dopant Li atom is initially placed in the interior. In some cases, before melting occurs, p-H2 molecules are ejected onto the slab surface and diffuse two dimensionally. Lithium is promoted to the surface only when it is initially buried in the surface layer or when the whole slab melts and a diffusion pathway is opened toward the surface.

Kinugawa, Kenichi; Moore, Preston B.; Klein, Michael L.

1998-07-01

424

Communication: Quantum molecular dynamics simulation of liquid para-hydrogen by nuclear and electron wave packet approach.  

PubMed

Liquid para-hydrogen (p-H2) is a typical quantum liquid which exhibits strong nuclear quantum effects (NQEs) and thus anomalous static and dynamic properties. We propose a real-time simulation method of wave packet (WP) molecular dynamics (MD) based on non-empirical intra- and inter-molecular interactions of non-spherical hydrogen molecules, and apply it to condensed-phase p-H2. The NQEs, such as WP delocalization and zero-point energy, are taken into account without perturbative expansion of prepared model potential functions but with explicit interactions between nuclear and electron WPs. The developed MD simulation for 100 ps with 1200 hydrogen molecules is realized at feasible computational cost, by which basic experimental properties of p-H2 liquid such as radial distribution functions, self-diffusion coefficients, and shear viscosities are all well reproduced. PMID:24811617

Hyeon-Deuk, Kim; Ando, Koji

2014-05-01

425

Structure-activity approach in the reactivation of tabun-phosphorylated human acetylcholinesterase with bispyridinium para-aldoximes.  

PubMed

We investigated interactions of bispyridinium para-aldoximes N,N'-(propano)bis(4-hydroxyiminomethyl) pyridinium bromide (TMB-4), N,N'-(ethano)bis(4-hydroxyiminomethyl)pyridinium methanosulphonate (DMB-4), and N,N'-(methano)bis(4-hydroxyiminomethyl)pyridinium chloride (MMB-4) with human erythrocyte acetylcholinesterase phosphorylated by tabun. We analysed aldoxime conformations to determine the flexibility of aldoxime as an important feature for binding to the acetylcholinesterase active site. Tabun-inhibited human erythrocyte acetylcholinesterase was completely reactivated only by the most flexible bispyridinium aldoxime - TMB-4 with a propylene chain between two rings. Shorter linkers than propylene (methylene or ethylene) as in MMB-4 and DMB-4 did not allow appropriate orientation in the active site, and MMB-4 and DMB-4 were not efficient reactivators of tabun-phosphorylated acetylcholinesterase. Since aldoximes are also reversible inhibitors of native acetylcholinesterase, we determined dissociation constants and their protective index against acetylcholinesterase inactivation by tabun. PMID:17562604

Kovarik, Zrinka; Cali?, Maja; Sinko, Goran; Bosak, Anita

2007-06-01

426

Matrix effect on the vibronic state of an atom embedded in a Solid Para-H2  

NASA Astrophysics Data System (ADS)

We have examined the matrix effect on the excitation spectra of Xe atom that is embedded in a solid state para-hydrogen (p-H2)n at liquid helium temperature, making use of the ab-initio molecular orbital calculation. The crystal structure of the solid (p-H2)n is hexagonal (hcp) and is known to be a quantum solid that may yield almost free ligand field for an atom located at a lattice point. However, the vibronic states made of p-H2 molecules coupled with the excited states of Xe atoms, which reflected significant matrix effect on the absorption spectrum in the ultraviolet-visible region. Similar effect on the emission spectra was also studied.

Nakagawa, S. T.; Sakane, G.; Senju, Y.; Kawaguchi, K.

2014-04-01

427

CURVA De ReFeReNCIA PeRUANA DeL PeSo De NACIMIeNTo PARA LA eDAD GeSTACIoNAL Y SU APLICACIÓN PARA LA IDeNTIFICACIÓN De UNA NUeVA PobLACIÓN NeoNATAL De ALTo RIeSGo  

Microsoft Academic Search

ReSUMeN El peso de nacimiento en relación con la edad gestacional, tiene valor pronóstico y sirve para el manejo clínico del recién nacido. La OMS recomienda patrones de crecimiento fetal en los centros perinatológicos, pues se detecta diferencias según países y condiciones de vida. Objetivos. Obtener una curva de referencia peruana del peso de nacimiento para la edad gestacional (CR-PNEG),

Manuel Ticona-Rendón; Diana Huanco-Apaza

428

Evaluation of take home (para-occupational) exposure to asbestos and disease: a review of the literature.  

PubMed

The potential for para-occupational (or "take-home") exposure to a number of chemicals has been recognized for over 60 years. We conducted a literature review in order to characterize reported cases of asbestos-related disease among household contacts of workers occupationally exposed to asbestos. Over 200 published articles were evaluated. Nearly 60 articles described cases of asbestos-related disease thought to be caused by para-occupational exposure. Over 65% of these cases were in persons who lived with workers classified as miners, shipyard workers, insulators, or others involved in the manufacturing of asbestos-containing products, with nearly all remaining workers identified as craftsmen. 98% of the available lung samples of the persons with diseases indicated the presence of amphibole asbestos. Eight studies provided airborne asbestos concentrations during (i) handling of clothing contaminated with asbestos during insulation work or simulated use of friction products; (ii) ambient conditions in the homes of asbestos miners; and (iii) wearing previously contaminated clothing. This review indicates that the literature is dominated by case reports, the majority of which involved household contacts of workers in industries characterized, generally, by high exposures to amphiboles or mixed mineral types. The available data do not implicate chrysotile as a significant cause of disease for household contacts. Also, our analysis indicates that there is insufficient information in the published literature that would allow one to relate airborne asbestos concentrations in a workplace to those that would be generated from subsequent handling of contact with clothing that had been contaminated in that environment. Ideally, a simulation study could be conducted in the future to better understand the relationships between the airborne concentrations in the workplace and the fiber characteristics that influence retention on fabric, as well as the concentrations that can be generated by handling the contaminated clothing by the persons in the home. PMID:22913651

Donovan, Ellen P; Donovan, Brooke L; McKinley, Meg A; Cowan, Dallas M; Paustenbach, Dennis J

2012-10-01

429

Trace amine-associated receptor 1 displays species-dependent stereoselectivity for isomers of methamphetamine, amphetamine, and para-hydroxyamphetamine.  

PubMed

The synthetic amines methamphetamine (METH), amphetamine (AMPH), and their metabolite para-hydroxyamphetamine (POHA) are chemically and structurally related to the catecholamine neurotransmitters and a small group of endogenous biogenic amines collectively referred to as the trace amines (TAs). Recently, it was reported that METH, AMPH, POHA, and the TAs para-tyramine (TYR) and beta-phenylethylamine (PEA) stimulate cAMP production in human embryonic kidney (HEK)-293 cells expressing rat trace amine-associated receptor 1 (rTAAR1). The discovery that METH and AMPH activate the rTAAR1 motivated us to study the effect of these drugs on the mouse TAAR1 (mTAAR1) and a human-rat chimera (hrChTAAR1). Furthermore, because S-(+)-isomers of METH and AMPH are reported to be more potent and efficacious in vivo than R-(-), we determined the enantiomeric selectivity of all three species of TAAR1. In response to METH, AMPH, or POHA exposure, the accumulation of cAMP by HEK-293 cells stably expressing different species of TAAR1 was concentration- and isomer-dependent. EC50 values for S-(+)-METH were 0.89, 0.92, and 4.44 microM for rTAAR1, mTAAR1, and h-rChTAAR1, respectively. PEA was a potent and full agonist at each species of TAAR1, whereas TYR was a full agonist for the rodent TAAR1s but was a partial agonist at h-rChTAAR1. Interestingly, both isomers of METH were full agonists at mTAAR1 and h-rChTAAR1, whereas both were partial agonists at rTAAR1. Taken together, these in vitro results suggest that, in vivo, TAAR1 could be a novel mediator of the effects of these drugs. PMID:17218486

Reese, E A; Bunzow, J R; Arttamangkul, S; Sonders, M S; Grandy, D K

2007-04-01

430

Surgical anatomy of the common iliac veins during para-aortic and pelvic lymphadenectomy for gynecologic cancer  

PubMed Central

Objective Compression of the left common iliac vein between the right common iliac artery and the vertebrae is known to be associated with the occurrence of left iliofemoral deep vein thrombosis (DVT). In this study, we described the variability in vascular anatomy of the common iliac veins and evaluated the relationship between the degree of iliac vein compression and the presence of DVT using the data from surgeries for gynecologic cancer. Methods The anatomical variations and the degrees of iliac vein compression were determined in 119 patients who underwent systematic para-aortic and pelvic lymphadenectomy during surgery for primary gynecologic cancer. Their medical records were reviewed with respect to patient-, disease-, and surgery-related data. Results The degrees of common iliac vein compression were classified into three grades: grade A (n=28, 23.5%), with a calculated percentage of 0%-25% compression; grade B (n=47, 39.5%), with a calculated percentage of 26%-50% compression; and grade C (n=44, 37%), with a calculated percentage of more than 50% compression. Seven patients (5.9%) had common iliac veins with anomalous anatomies; three were divided into small caliber vessels, two with a flattened structure, and two had double inferior vena cavae. The presence of DVT was associated with the elevated D-dimer levels but not with the degree of iliac vein compression in this series. Conclusion Although severe compression of the common iliac veins was frequently observed, the degree of compression might not be associated with DVT in surgical patients with gynecologic cancer. Anomalous anatomies of common iliac veins should be considered during systematic para-aortic and pelvic lymphadenectomy in the gynecologic cancer patients.

Tate, Shinichi; Nishikimi, Kyoko; Shozu, Makio

2014-01-01

431

Analysis of para-aortic lymphadenectomy up to the level of the renal vessels in apparent early-stage ovarian cancer  

PubMed Central

Objective The aim of this study was to evaluate the impact of para-aortic lymphadenectomy up to the renal vessels on the accurate staging in ovarian cancer patients presumed preoperatively to be confined to the ovary. Methods We retrospectively analyzed data on 124 patients with primary epithelial ovarian cancer who were preoperatively thought to have tumor confined to the ovary and underwent primary staging surgery. The distribution of lymph node metastasis and various risk factors for nodal involvement were investigated. Results Surgical staging yielded: 87 (70.2%) patients had International Federation of Gynecology and Obstetrics (FIGO) stage I disease and 37 (29.8%) patients had stage II-III disease: 4 IIA, 6 IIB, 9 IIC, 1 IIIA, and 17 IIIC. Eighty-six patients had pelvic lymphadenectomy only and 69 had pelvic and para-aortic lymphadenectomy. Lymph node metastases were found in 17 (24.6%) of 69 patients; 5 (7.2%) patients had lymph node metastasis in the pelvic lymph nodes only, 8 (11.6%) in the para-aortic lymph nodes only, and 4 (5.8%) in both pelvic and para-aortic lymph nodes. Six (8.7%) patients had lymph node metastasis in the para-aortic lymph node above the level of the inferior mesenteric artery. On multivariate analysis, grade 3 tumor (p=0.01) and positive cytology (p=0.03) were independent predictors for lymph node metastasis. Conclusion A substantial number of patients with apparently early ovarian cancer had upstaged disease. Of patients who underwent lymphadenectomy, some patients had lymph node metastasis above the level of the inferior mesenteric artery. Para-aortic lymphadenectomy up to the renal vessels may detect occult metastasis and be of help in tailoring appropriate adjuvant treatment as well as giving useful information about the prognosis.

Ryu, Hee-Sug

2013-01-01

432

Molecular recognition: influence of para-versus-meta-substituted phenyl moieties on the swelling degree of macroscopic polymeric gels in aqueous cyclodextrin solutions.  

PubMed

Free radical terpolymerization of (N,N)-dimethylacrylamide, ethylene-glycol-dimethacrylate and N-(p- or m-ethyl-phenyl)acrylamide leads to para- and meta-ethyl-phenyl-modified hydrophilic polymer networks. Polymeric networks of different molar ratios are prepared in special molds to give water swellable disc- shaped samples. The swelling behavior in water and aqueous cyclodextrin (CD) solution of the obtained samples is described while a distinctive differentiation between the para- and meta-ethyl-phenyl containing networks in CD solution can be found. PMID:23996828

van Sloun, Claudia; Peters, Oliver; Tabatabai, Monir; Ritter, Helmut

2013-10-01

433

Herschel/HIFI measurements of the ortho/para ratio in water towards Sagittarius B2(M) and W31C  

NASA Astrophysics Data System (ADS)

We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-H_216O and H_218O in absorption towards Sagittarius B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is generally consistent with the statistical high-temperature ratio of 3, within the observational uncertainties. However, somewhat unexpectedly, we derive a low ortho/para ratio of 2.35 ± 0.35, corresponding to a spin temperature of ~27 K, towards Sagittarius B2(M) at velocities of the expanding molecular ring. Water molecules in this region appear to have formed with, or relaxed to, an ortho/para ratio close to the value corresponding to the local temperature of the gas and dust. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Lis, D. C.; Phillips, T. G.; Goldsmith, P. F.; Neufeld, D. A.; Herbst, E.; Comito, C.; Schilke, P.; Müller, H. S. P.; Bergin, E. A.; Gerin, M.; Bell, T. A.; Emprechtinger, M.; Black, J. H.; Blake, G. A.; Boulanger, F.; Caux, E.; Ceccarelli, C.; Cernicharo, J.; Coutens, A.; Crockett, N. R.; Daniel, F.; Dartois, E.; de Luca, M.; Dubernet, M.-L.; Encrenaz, P.; Falgarone, E.; Geballe, T. R.; Godard, B.; Giesen, T. F.; Goicoechea, J. R.; Gry, C.; Gupta, H.; Hennebelle, P.; Hily-Blant, P.; Ko?os, R.; Kre?owski, J.; Joblin, C.; Johnstone, D.; Ka?mierczak, M.; Lord, S. D.; Maret, S.; Martin, P. G.; Martín-Pintado, J.; Melnick, G. J.; Menten, K. M.; Monje, R.; Mookerjea, B.; Morris, P.; Murphy, J. A.; Ossenkopf, V.; Pearson, J. C.; Pérault, M.; Persson, C.; Plume, R.; Qin, S.-L.; Salez, M.; Schlemmer, S.; Schmidt, M.; Sonnentrucker, P.; Stutzki, J.; Teyssier, D.; Trappe, N.; van der Tak, F. F. S.; Vastel, C.; Wang, S.; Yorke, H. W.; Yu, S.; Zmuidzinas, J.; Boogert, A.; Erickson, N.; Karpov, A.; Kooi, J.; Maiwald, F. W.; Schieder, R.; Zaal, P.

2010-10-01

434

Removal of Arsenic in Drinking Water Kinetico Inc. and Alcan Chemicals Para-Flo? PF60 Model AA08AS with Actiguard AAFS50  

EPA Science Inventory

Testing of the Kinetico Inc. and Alean Chemicals Para-FloTM PF60 Model AA08AS with Actiguard AAFS50 arsenic adsorption media filter system was conducted at the Orchard Hills Mobile Home Park (MHP) Water Treatment Plant (WTP) in Carroll Township, Pennsylvania. The source water,...

435

ANÁLISIS JURÍDICO PARA DETERMINAR LA VIOLACIÓN A LOS PRINCIPIOS DE; CONSTITUCIONALIDAD, LEGALIDAD Y SEGURIDAD, EN EL ARTÍCULO 215 DE LA LEY DEL IMPUESTO SOBRE LA RENTA  

Microsoft Academic Search

El objetivo de esta investigación fue determinar si las disposiciones fiscales del artículo 215 de la Ley del Impuesto sobre la Renta (LISR), sobre precios de transferencia a las empresas partes relacionadas, a las cuales les indica que deberán apegarse a la Guía de la Organización para la Cooperación y el Desarrollo Económico (OCDE), violentan los principios de constitucionalidad, legalidad

Martha Luisa Puente Esparza; J. Humberto González Álvarez

2011-01-01

436

Mapping regional land cover with MODIS data for biological conservation: Examples from the Greater Yellowstone Ecosystem USA and Para´ State Brazil  

Microsoft Academic Search

Abstract The paper investigated the application of MODIS data for mapping regional land cover at moderate resolutions (250 and 500 m), for regional conservation purposes. Land cover maps were generated for two major conservation areas (Greater Yellowstone Ecosystem—GYE, USA and the Para´ State, Brazil) using MODIS data and decision tree classifications. The MODIS land cover products were evaluated using existing

K. j. Wessels; R. s. De Fries; J. Dempewolf; L. o. Anderson; A. j. Hansen

437

Poder de mercado das exportações brasileiras de carne bovina in natura para a União Européia Grupo de Pesquisa: Comercialização, Mercados e Preços  

Microsoft Academic Search

Resumo: A União Européia é o principal mercado do setor ex portador de carne bovina do Brasil e é marcado por práticas de protecionismo qu e distorcem o equilíbrio de mercado. Além disso, as exportações brasileiras para a UE do tipo in natura vêm sofrendo quedas contínuas. Neste contexto, o principal objetivo des te trabalho foi mensurar o poder de

Apresentação Oral-Comercialização; ALINE CRISTINA CRUZ; MARCELO JOSE BRAGA

438

Relationship between the features of the mechanism of the ortho-para conversion of hydrogen on magnetic surfaces and the macroscopic rate of the process  

SciTech Connect

The well-founded nature of the previously proposed ideas concerning the mechanism of the ortho-para conversion of hydrogen on magnetic surfaces has been demonstrated in light of the experimental data which has been accumulated on the macroscopic rate of this process. The close interrelationship between all the principle hypotheses on the mechanism has been demonstrated.

Golovin, A.V.

1986-11-01

439

CENTRO UNIVERSITARIO MUNICIPAL LAJAS – GOBIERNO: UN EJEMPLO DE INTEGRACIÓN PARA LA ELABORACIÓN, SEGUIMIENTO Y MONITOREO DE LA ESTRATEGIA DE DESARROLLO LOCAL  

Microsoft Academic Search

En la presente investigación se elabora la estrategia de desarrollo local del municipio de Lajas, fusionando el trabajo del Centro Universitario Municipal y el gobierno del territorio, para la misma se hace un análisis histórico-lógico de la concepción de la gestión de proyectos y estrategias en función del desarrollo local, su objetivo principal es lograr de forma coordinada la resolución

Maribel Estrada Martín; Pedro Rafael Pretel Olite; Liliana Llanes Robaina

2012-01-01

440

El Gobierno de las Entidades no Lucrativas. Evidencia emp¡rica para las Organizaciones no Gubernamentales de Cooperaci¢n al Desarrollo Espa¤olas  

Microsoft Academic Search

La ausencia de derechos residuales en las entidades no lucrativas (non profit) singulariza el problema de gobierno tradicionalmente estudiado. En este contexto, el objetivo de este trabajo es verificar la existencia y relevancia de los mecanismos de control para evitar la expropiaci¢n de recursos por parte de los directivos e incrementar la eficiencia en una muestra representativa de las Organizaciones

2003-01-01

441

Final Report on the Reproductive Toxicity of Meta-/Para-Cresol (MPCRE) (CAS No. 1319-77-3) in Swiss Mice. Laboratory Supplement. Volume 2.  

National Technical Information Service (NTIS)

In preparing to test the reproductive toxicity of a mixture of meta-cresol and para-cresol on mice, general product information is presented, as is data on metabolism, pharmacokinetics, known toxicities, and use of live animals. In addition, dosage formul...

J. D. George M. K. Izard P. A. Fail T. B. Grizzle

1992-01-01

442

Refinement of the experimental dynamic structure factor for liquid para-hydrogen and ortho-deuterium using semi-classical quantum simulation  

NASA Astrophysics Data System (ADS)

The dynamic structure factor of liquid para-hydrogen and ortho-deuterium in corresponding thermodynamic states (T = 20.0 K, n = 21.24 nm-3) and (T = 23.0 K, n = 24.61 nm-3), respectively, has been computed by both the Feynman-Kleinert linearized path-integral (FK-LPI) and Ring-Polymer Molecular Dynamics (RPMD) methods and compared with Inelastic X Ray Scattering spectra. The combined use of computational and experimental methods enabled us to reduce experimental uncertainties in the determination of the true sample spectrum. Furthermore, the refined experimental spectrum of para-hydrogen and ortho-deuterium is consistently reproduced by both FK-LPI and RPMD results at momentum transfers lower than 12.8 nm-1. At larger momentum transfers the FK-LPI results agree with experiment much better for ortho-deuterium than for para-hydrogen. More specifically we found that for k ˜ 20.0 nm-1 para-hydrogen provides a test case for improved approximations to quantum dynamics.

Smith, Kyle K. G.; Poulsen, Jens Aage; Cunsolo, A.; Rossky, Peter J.

2014-01-01

443

Selective Oxidation of 8,8'-Hydroxylated Binaphthols to Bis-spironaphthalenones or Binaphtho-para- and Binaphtho-ortho-quinones  

PubMed Central

The selective oxidation of a series of functionalized 8,8'-hydroxylated binaphthols to binaphtho-para- and binaphtho-ortho-quinones has been realized using either a Co-salen catalyst or ortho-iodoxybenzoic acid. A unique spirocyclic bis-spironaphthalenone was also obtained in good yield via a phenyliodonium diacetate promoted oxidative dearomatization.

Podlesny, Erin E.; Carroll, Patrick J.; Kozlowski, Marisa C.

2012-01-01

444

Efectividad de un Programa de Promoción de Actividad Física (PPAF) desde los centros de atención primaria para aumentar los niveles de actividad física en población sedentaria  

Microsoft Academic Search

Introducción. La inactividad física es un factor de riesgo modificable de desarrollo de enfermedades crónicas. La elevada proporción de adultos sedentarios que acuden a los Centros de Atención Primaria (CAP) justifica las intervenciones de promoción de Actividad Física (AF) desde este ámbito. Objetivo. Evaluar la efectividad de un Programa de Promoción de Actividad Física (PPAF) desde Atención Primaria (AP) para

Martin-Borràs Carme; Giné-Garriga Maria; Martín-Cantera Carlos; Puig-Ribera Anna; Duran-Bellido Eulàlia; Solà-Gonfaus Mercè; PPAF grupo

2002-01-01

445

SIMULACIÓN DE UN PROTOCOLO DE NIVEL MAC BASADO EN IEEE 802.16 PARA EL LABORATORIO DE ARQUITECTURA DE REDES I  

Microsoft Academic Search

Este trabajo presenta nuestra experiencia en el desarrollo de una herramienta de simulación de protocolos de nivel MAC basados en el estándar IEEE 802.16 (1). El empleo de esta herramienta en el laboratorio ayuda a los alumnos en el estudio y comprensión de protocolos de redes de última milla. En particular, se ha definido un protocolo de nivel MAC para

O. RIVERA; I. GÓMEZ; V. MEDINA

446

Enzymoblotting: a method for localizing proteinases and their zymogens using para-nitroanilide substrates after agarose gel electrophoresis and transfer to nitrocellulose.  

PubMed

A method--enzymoblotting--was developed for localizing various enzymes after electrophoretic separation, transfer to nitrocellulose, and incubation with specific substrates. As an application, the proteinases porcine trypsin (EC 3.4.21.4), bovine chymotrypsin (EC 3.4.21.1), porcine elastase (EC 3.4.22.11), and their zymogen forms from porcine pancreas homogenate were analyzed utilizing specific p-nitroanilide substrates. After agarose gel electrophoresis, transfer of the separated proteinases to a nitrocellulose membrane was performed by capillary diffusion for 30 min. After air-drying of the nitrocellulose membrane, it was incubated in the appropriate substrate solution for 60 min. N-alpha-Benzoyl-DL-arginine-para-nitroanilide HCl was used as a substrate for trypsin, N-benzoyl-L-tyrosine-para-nitroanilide and succinyl-L-phenylalanine-para-nitroanilide for chymotrypsin, and N-succinyl-L-alanyl-L-alanyl-L-alanine-para-nitroanilide for elastase. p-Nitroaniline, the product thus obtained, was diazotized with N-(1-naphthyl)ethylenediamine to a red azo dye, visible at the site of the proteinases on the nitrocellulose membrane. The results could be preserved at -18 degrees C. Zymogen forms of the pancreas proteinases were detected in a similar manner. They were converted to active proteinases in situ on the nitrocellulose membrane after preincubating the nitrocellulose membrane in the activation enzymes enteropeptidase or trypsin. PMID:3516006

Ohlsson, B G; Weström, B R; Karlsson, B W

1986-02-01

447

High-dose Extended-Field Irradiation and High-Dose-Rate Brachytherapy With Concurrent Chemotherapy for Cervical Cancer With Positive Para-Aortic Lymph Nodes  

SciTech Connect

Purpose: To determine the efficacy and toxicity of extended-field radiotherapy (RT) with concurrent platinum-based chemotherapy in patients with uterine cervical carcinoma and positive para-aortic nodes. Methods and Materials: We retrospectively reviewed the results for 33 women with Stage IB-IVB cervical cancer. Each patient had received 59.4 Gy, including a three-dimensional conformal boost to the para-aortic lymph nodes and 41.4-50.4 Gy of external beam radiotherapy to the pelvis. Each patient also underwent six or seven applications of high-dose-rate brachytherapy (median, 5 Gy to point A at each session). Results: The median follow-up period of surviving patients was 39 months. The most common acute toxicity was hematologic, observed in 23 women. Severe acute and late gastrointestinal toxicity was observed in 3 and 4 patients, respectively. More than three-quarters of patients showed a complete response, encompassing the primary mass, metastatic pelvic, and para-aortic lymph nodes. Of the 33 women, 15 had no evidence of disease, 6 had persistent disease, 4 developed in-field failures, and 6 developed distant failures. The 5-year overall and disease-free survival rate was 47% and 42%, respectively. Conclusion: Concurrent chemoradiotherapy with extended-field radiotherapy is feasible in women with uterine cervical carcinoma and positive para-aortic lymph nodes, with acceptable late morbidity and a high survival rate, although it was accompanied by substantial acute toxicity.

Kim, Young Seok; Kim, Jong Hoon; Ahn, Seung Do; Lee, Sang-wook; Shin, Seong Soo [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Nam, Joo-Hyun; Kim, Young-Tak; Kim, Yong-Man; Kim, Jong-Hyeok [Department of Obstetrics and Gynecology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Eun Kyung [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)], E-mail: ekchoi@amc.seoul.kr

2009-08-01

448

Autoras de obras didáticas e livros para o ensino da leitura produzidos no Rio Grande do Sul: contribuições à história da alfabetização (1950-1970)1  

Microsoft Academic Search

Resumo: A História da Alfabetização tem se constituído um importante campo de pesquisa no Brasil nos últimos anos, enfatizando, entre outras coisas, métodos e processos de ensino da leitura e da escrita, materiais de alfabetização, com destaque para as cartilhas escolares, histórias e trajetórias de vida de professoras alfabetizadoras, etc. Na pesquisa que realizamos desde 2001, temos privilegiado a análise

Eliane Peres

449

Mapping regional land cover with MODIS data for biological conservation: Examples from the Greater Yellowstone Ecosystem, USA and ParaState, Brazil  

Microsoft Academic Search

The paper investigated the application of MODIS data for mapping regional land cover at moderate resolutions (250 and 500 m), for regional conservation purposes. Land cover maps were generated for two major conservation areas (Greater Yellowstone Ecosystem—GYE, USA and the ParaState, Brazil) using MODIS data and decision tree classifications. The MODIS land cover products were evaluated using existing Landsat TM

K. J. Wesselsa; J. Dempewolfa; A. J. Hansend; E. F. Morane

450

LA GESTIÓN DE RESIDUOS EN LA EMPRESA: MOTIVACIONES PARA SU IMPLANTACIÓN Y MEJORAS ASOCIADAS \\/ FIRMS’ WASTE MANAGEMENT IN THE COMPANY: MOTIVATIONS FOR THEIR IMPLEMENTATION AND ASSOCIATED IMPROVEMENTS  

Microsoft Academic Search

Entre los problemas medioambientales actuales, la reducción o eliminación de los residuos se ha convertido en una de las principales preocupaciones en los países industrializados y en una prioridad para las empresas. En el presente trabajo se realiza una revisión de los postulados del modelo económico clásico, vigente hasta hace escasas fechas, en relación con la variable medio ambiente y

Unai Tamayo Orbegozo; María Azucena Vicente Molina; Julen Izaguirre Olaizola

2012-01-01

451

Auditoría al sistema de gestión ambiental de una cementera para determinar los porcentajes de adecuación a la norma venezolana covenin - iso 14001:2005  

Microsoft Academic Search

El presente trabajo consiste en la combinación de técnicas de evaluación propias de estudios ambientales con procedimientos de auditoría tradicionales, con el objetivo de auditar el Sistema de Gestión Ambiental (SGA) de una empresa cementera venezolana llamada Cementos Carora C. A. siguiendo los lineamientos de la norma venezolana COVENIN ISO 14001:2005 para determinar los porcentajes de adecuación a la norma.

Alexis Colmenárez; Anoushka Colménarez

2008-01-01

452

PROCEDIMIENTO PARA EL DISEÑO E IMPLANTACIÓN DEL SISTEMA INTEGRADO DE GESTIÓN DE LA CALIDAD, GESTIÓN AMBIENTAL Y GESTIÓN DE LA SEGURIDAD Y SALUD EN EL TRABAJO  

Microsoft Academic Search

El este trabajo se presenta una propuesta de un procedimiento para la implantación de un sistema integrado de gestión. Basado en el enfoque a procesos y la filosofía de la mejora continua que permite integrar en un mismo sistema, la gestión de la calidad, gestión ambiental y gestión de la seguridad y salud en el trabajo. La implementación del procedimiento

Yonimiler Rodríguez García; Yurebi Cruz Cordovés

2009-01-01