A new baseline for fascioliasis in Venezuela: lymnaeid vectors ascertained by DNA sequencing and analysis of their relationships with human and animal infection

Directory of Open Access Journals (Sweden)

Artigas Patricio

2011-10-01

Full Text Available Abstract Background Human and animal fascioliasis poses serious public health problems in South America. In Venezuela, livestock infection represents an important veterinary problem whereas there appear to be few human cases reported, most of which are passively detected in health centres. However, results of recent surveys suggest that the situation may be underestimated in particular areas. To obtain a baseline for future fascioliasis assessment, studies were undertaken by means of rDNA ITS-2 and ITS-1 and mtDNA cox1 sequencing to clarify the specific status of Venezuelan lymnaeids, their geographical distribution and fascioliasis transmission capacity, by comparison with other American countries and other continents. Results Results obtained completely change the lymnaeid scenario known so far. The relatively rich lymnaeid fauna of Venezuela has been proven to include (i Lymnaea meridensis and L. neotropica as the only native members, (ii L. cubensis and Pseudosuccinea columella introduced from the Caribbean area, and (iii Galba truncatula and L. schirazensis introduced from the Old World. The absence of representatives of the stagnicoline and Radix groups is remarkable. Four species are fascioliasis vectors: G. truncatula, L. cubensis and L. neotropica, which have the capacity to give rise to human endemic areas, and P. columella, which is a source of animal infection and is responsible for the spread of disease. Vector capacity in the apparently highland endemic L. meridensis is to be confimed, although may be expected given its phylogenetic relationships. Similarly as elsewhere, the non-transmitting L. schirazensis has been confused with L. cubensis, also with G. truncatula and possibly with L. neotropica. Conclusions The new scenario leads to the re-opening of many disease aspects. In Venezuela, altitude appears to be the main factor influencing fascioliasis distribution. Human infection shows an altitude pattern similar to other Andean

COLOFONIA DE PINÁCEAS CUBANAS PARA EL CONTROL DE ENFERMEDADES TROPICALES TRANSMITIDAS POR MOLUSCOS

Directory of Open Access Journals (Sweden)

Y. Arteaga-Crespo

2010-01-01

Full Text Available La esquistosomiasis, enfermedad tropical transmitida por molusco, ocupa el segundo lugar en enfermedades parasitarias después de la malaria. En Cuba no existe la esquistosomiasis aunque sí el riesgo a contraerla, puesto que en nuestra fauna se encuentran especies que pueden actuar como hospederos intermediarios del tremátodo causante de la enfermedad. El objetivo del trabajo fue evaluar el polvo de colofonia sobre larvas de Biomphalaria havanensis para el control de vectores que propagan la esquistosomiasis, según la metodología desarrollada por la Organización Mundial para la Salud (OMS y descrita por Mott para la evaluación de plantas con acción molusquicida. Los resultados del estudio sugieren la acción molusquicida de colofonia obtenida de pináceas cubanas (Pinus caribaea y Pinus tropicalis sobre larvas de Biomphalaria havanensis en dosis letales (DL50 y DL90 son 44, 33 mg·L-1 y 141, 76 mg·L-1, respectivamente. La ecuación de regresión correspondiente fue: Y = - 0, 412 + 1, 086 ln X con un valor del coeficiente de correlación R 0, 99 y error estándar 0, 13. Las dosis revelan la efectividad de los componentes presentes en la colofonia, resultados comparables con publicaciones de extractos de otras especies de plantas.

Alteration of Depressive-like Behaviors by Psilocybe cubensis Alkaloid Extract in Mice: the Role of Glutamate Pathway

Directory of Open Access Journals (Sweden)

Elaheh Mahmoudi

2018-03-01

Full Text Available Background and objectives: Considering the increasing prevalence of depression, many studies are launched to investigate new antidepressant treatments. The present research has shown how psilocybin as an active compound of Psilocybe cubensis (Earle Singer extract (PCE can change the parameters related to depression and anxiety in animal models. Both serotonin (5-hydroxytryptamine: 5-HT and glutamate modulate depressive-like behaviors and, therefore, we examined the possible interaction of psilocybin as 5-HT1 agonist with glutamate receptor N-methyl-D-aspartate (NMDA. Methods: Psilocybe cubensis extract of this mushroom was prepared by ethyl acetate. NMRI mice involved in all experiments and were treated with the vehicle, extract, or standard drug intraperitoneally. Open field (OFT, forced swimming (FST and tail suspension tests (TST were applied to measure the intended parameters. OFT was performed to verify the applied doses for measuring the following antidepressant activity.  Results: PCE at the doses of 100 mg/kg significantly changed the locomotion, time spent in center and velocity of the animals in OFT. While treatment of the animals with PCE 10 and 40 mg/kg or ketamine 1 mg/kg did not alter the locomotor activity, co-administration of these subeffective amounts significantly reduced the immobility time in both FST and TST. Conclusion: These effects may indicate possible implication of psilocybin with NMDA receptor which consequently produces the antidepressant effects.

Relação entre a patogenicidade do Schistosoma mansoni em camundongos e a susceptibilidade do molusco vetor: III. Mortalidade, pesos corporal e das vísceras

Directory of Open Access Journals (Sweden)

Zanotti-Magalhães Eliana Maria

1995-01-01

Full Text Available Estudou-se a relação entre o desenvolvimento da hepatomegalia, da esplenomegalia, peso corporal e taxa de mortalidade em camundongos experimentalmente infectados por Schistosoma mansoni com o grau de susceptibilidade de Biomphalaria glahrata e B. tenagophila nas quais se desenvolveram as cercárias infectantes respectivamente, das linhagens BH e SJ. Foram utilizados como hospedeiro definitivo camundongos Swiss, SPF e como hospedeiros intermediários populações de moluscos selecionados geneticamente para o caráter susceptibilidade. Foram observados menores pesos corporais e das visceras em camundongos infectados com cercárias provenientes de moluscos que apresentaram elevado grau de susceptibilidade. A maior susceptibilidade dos moluscos à infecção pelo S. mansoni correspondeu a uma menor sobrevivência dos camundongos infectados. Os resultados fazem crer que a maior adaptação do parasita ao hospedeiro intermediário, traduzidos pelas taxas mais elevadas de susceptibilidade, pode levar a um comportamento diferente deste parasita no hospedeiro definitivo.

Assessment of the FasciMol-ELISA in the detection of the trematode Fasciola hepatica in field-collected Galba cubensis: a novel tool for the malacological survey of fasciolosis transmission.

Science.gov (United States)

Alba, Annia; Vázquez, Antonio A; Sánchez, Jorge; Fraga, Jorge; Hernández, Hilda; Martínez, Elizabeth; Marcet, Ricardo; Figueredo, Mabel; Sarracent, Jorge

2016-01-16

Fasciolosis is one of the food-borne neglected trematodioses that has reemerged as a human disease while its effects on domestic animal health remains of significant economic consideration. Being snail-borne disease, the accurate and time-saving epidemiological surveillance of the transmission foci where infected lymnaeid snails occur could be essential to effectively focus or redirect control strategies. For this purpose, the first monoclonal antibody-based immunoenzymatic assay to detect Fasciola hepatica-infected snails (FasciMol-ELISA) was recently developed and showed a high sensitivity and specificity when tested in an experimental F. hepatica - Galba cubensis system. Here, we surveyed populations of G. cubensis occurring in western Cuba for the assessment of the FasciMol-ELISA in determining natural F. hepatica infection in this intermediate host. A multiplex PCR, previously developed to detect F. hepatica in G. cubensis, was used for sample classification. Snail dissection method was also employed as screening technique. A Χ(2) test and a Kappa index were calculated to evaluate the positivity and the level of agreement between the FasciMol-ELISA and the snail dissection methods with the multiplex PCR, respectively. Galba cubensis was found in nine out of 12 sampled localities of which four were positive for F. hepatica infection as detected by both immunoenzymatic and PCR-based assays. The overall prevalence was higher than the natural infection rates previously reported for Cuban G. cubensis (range from 4.1 to 7.42% depending on the screening method). No significant differences were found between FasciMol-ELISA and multiplex PCR when determining parasite positivity (Χ(2) = 6.283; P = 0.0981) whereas an excellent agreement was also noted (Kappa = 0.8224). Our results demonstrate the importance of malacological surveys in assessing parasite transmission risk and constitute an alert on the need of accurate measures to control fasciolosis in

Responses of freshwater molluscs to environmental factors in Southern Brazil wetlands Respostas de moluscos límnicos a fatores ambientais em áreas úmidas do sul do Brasil

Directory of Open Access Journals (Sweden)

L. Maltchik

2010-08-01

Full Text Available Freshwater molluscs play an important role in aquatic ecosystems, providing food for many fish species and vertebrates. Investigations on factors that determine mollusc species richness and distribution in wetland systems are scarce in the Neotropical region. The main goal of this study was to determine how much variation in mollusc richness and composition is explained by area, hydroperiod, altitude, water conductivity, and dominant aquatic vegetation. This survey was performed in an extensive area of a Neotropical region (~280,000 km² in southern Brazil, with a large number of wetland systems (111 and covering a wide gradient of altitude and wetland surface area. The mollusc richness was positively associated with wetland area and negatively associated with altitude. The richness and composition of the freshwater molluscs were similar between permanent and intermittent wetlands and it did not differ significantly between aquatic bed and emergent wetlands. The first three axes of CCA explained 16.2% of the total variation in the composition of the freshwater mollusc observed. The variation in the composition had a correlation with wetland area, altitude and water conductivity. Our results showed that the wetlands are important habitats for molluscs in southern Brazil, and that the richness and the composition of molluscs were associated with area, altitude, water conductivity and dominant vegetation.Moluscos límnicos desempenham um papel importante em ecossistemas aquáticos, fornecendo alimento para diversos peixes e vertebrados. Investigações sobre os fatores que determinam a riqueza e a distribuição das espécies de moluscos em áreas úmidas são escassos na região neotropical. O principal objetivo deste estudo foi determinar a variação na riqueza e na composição de moluscos em função da área, hidroperíodo, altitude, condutividade da água e tipo de vegetação aquática dominante. Este estudo foi desenvolvido em uma extensa

Centrocestus formosanus (Opisthorchiida: Heterophyidae como causa de muerte de alevines de tilapia gris Oreochromis niloticus (Perciforme: Cichlidae en el Pacífico seco de Costa Rica

Directory of Open Access Journals (Sweden)

Donald Arguedas Cortés

2010-12-01

Full Text Available Centrocestus formosanus es un parásito trematodo zoonótico originario de Asia asociado con muertes de peces principalmente de cultivo. 907 moluscos provenientes de estanques sembrados con tilapias, seleccionados uno por provincia fueron identificados al nivel taxonómico especifico. Se identificaron cuatro gastrópodos y un bivalvo: M. tuberculata, M. turricula, P. flagellata, H. cubensis y A. luteola. Se reporta, por primera vez, la presencia de dos especies de moluscos en Costa Rica. Se identificaron siete morfotipos de cercarias parasitando las cinco especies de moluscos encontradas. En la segunda exposición experimental se demostró que el morfotipo parapleurolofocercus encontrado en M. tuberculata concuerda con el hallazgo de C. formosanus en alevines de tilapia, después del examen clínico, anatomopatológico y parasitológico realizado a los alevines expuestos. Las metacercarias fueron extraídas del quiste utilizando microagujas y micropinzas lavadas en solución salina fisiológica (0.65%, fijadas en formol caliente al 4% y después esquematizadas con una cámara clara adaptada a un microscopio fotónico, estimándose una abundancia e intensidad media de 1018-1027 digeneos por branquia en cada pez parasitado, determinándose así el hospedador intermediario primario y secundario del parásito. En el presente trabajo se reporta por primera vez Centrocestus formosanus en Costa Rica.

Distinción taxonómica de los moluscos de fondos blandos del Golfo de Batabanó, Cuba

Directory of Open Access Journals (Sweden)

Norberto Capetillo-Piñar

2015-11-01

Full Text Available La distinción taxonómica es una medida de diversidad que presenta una serie de ventajas que dan connotación relevante a la ecología teórica y aplicada. La utilidad de este tipo de medida como otro método para evaluar la biodiversidad de los ecosistemas marinos bentónicos de fondos blandos del Golfo de Batabanó (Cuba se comprobó mediante el uso de los índices de distinción taxonómica promedio (Delta+ y la variación en la distinción taxonómica (Lambda+ de las comunidades de moluscos. Para este propósito, se utilizaron los inventarios de especies de moluscos bentónicos de fondos blandos obtenidos en el periodo 1981-1985 y en los años 2004 y 2007. Ambos listados de especies fueron analizados y comparados a escala espacial y temporal. La composición taxonómica entre el periodo y años estudiados se conformó de 3 clases, 20 órdenes, 60 familias, 137 géneros y 182 especies, observándose, excepto en el nivel de clase, una disminución no significativa de esta composición en 2004 y 2007. A escala espacial se detectó una disminución significativa en la riqueza taxonómica en el 2004. No se detectaron diferencias significativas en Delta+ y Lambda+ a escala temporal, pero si a escala espacial, hecho que se puede atribuir al efecto combinado del incremento de las actividades antropogénicas en la región con los efectos inducidos por los huracanes. Estos resultados sugieren que el par de índices Delta+ y Lambda+ son buenos descriptores de la biodiversidad de las comunidades de moluscos bentónicos de fondos blandos del Golfo de Batabanó.

Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

Directory of Open Access Journals (Sweden)

Juan Francisco Sánchez Pérez

2008-12-01

Full Text Available El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso pertenece a la familia Poxvirus, virus ADN relacionados entre sí, que son infectivos para animales vertebrados e invertebrados. Las lesiones se contagian por contacto directo con personas infectadas o con objetos contaminados y suele afectar a la población en edad escolar, produciéndose en determinadas situaciones verdaderas epidemias. En noviembre de 2008 se recibió en el Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Región de Murcia una llamada telefónica del Servicio de Epidemiología de la misma consejería, en la que se comunicaba la existencia de aproximadamente 12-15 casos de niños afectados por molusco contagioso indicándose además, que las sospechas recaían sobre la piscina municipal cubierta de Alhama de Murcia. Inmediatamente se contactó con el personal responsable de la instalación, enviándoles un protocolo de actuaciones elaborado con información obtenida de diversas fuentes de información. Tras la búsqueda bibliográfica se seleccionó como indicador el parámetro ausencia de mohos y levaduras. Los resultados obtenidos en la toma de muestras de los artículos propios de la piscina mostraron ausencia de molusco contagioso, coincidiendo con la no aparición de más casos. Meses más tarde, en marzo de 2009, se detectaron de nuevo casos de niños afectados en otra piscina del municipio de Alcantarilla. Debido al éxito de la metodología utilizada en el incidente an- terior, se realizaron idénticas actuaciones, obteniéndose idénticos resultados. A la vista de los resultados obtenidos, el protocolo elaborado por este servicio se mostró efectivo para detener la aparición de más casos, puesto que no ocurrió ninguna incidencia posterior, y se

Resurrection of Scolopendra longipes Wood and Scolopendra cubensis Saussure from synonymy with Scolopendra alternans Leach (Chilopoda, Scolopendromorpha, Scolopendridae): an enigmatic species-group needing phylogeographic analysis, with an overview on the origin and distribution of centipedes in the Caribbean region.

Science.gov (United States)

Mercurio, Randy J

2016-05-12

Resurrection of Scolopendra longipes Wood, 1862, and Scolopendra cubensis Saussure, 1860, from junior synonymy with Scolopendra alternans Leach, 1815, is proposed. A neotype specimen of Scolopendra longipes is designated. Scolopendra longipes has a restricted range from the Dry Tortugas up through the Florida Keys of Monroe County into the mainland Florida counties of Collier and Dade southeast to the Bahamas, while Scolopendra cubensis is endemic to Cuba. Characters distinguishing S. longipes, and S. cubensis from S. alternans are illustrated and compared using digital photography, micrography and morphometric data. It is suggested that what has been considered Scolopendra alternans from southern Florida through the Caribbean and into northern South America is probably an evolving species-group that has undergone major diversification sometime during the Paleocene and early Eocene ~65.5-50 million years ago (Ma), mainly due to geographic isolation caused by a combination of plate tectonics and 100,000 year cycles of glaciation/deglaciation.

Moluscos marinos de la Isla de Gorgona (Costa del Pacífico colombiano)

OpenAIRE

Cosel, R.v.

1984-01-01

Se listan 319 especies de moluscos marinos ya recolectados por varias personas y expediciones científicas en la Isla Gorgona (Litoral Pacífico de Colombia, provincia zoogeográfica panameña). 209 especies (65.5%) se encuentran desde México hasta el Ecuador o Perú, 21 especies (6.6%) desde Centroamérica hasta el Ecuador o Perú y 4 especies (1.3%) desde Gorgona (límite norte) hasta el Ecuador o Perú. Para 42 especies (13.2%), Gorgona forma el límite sur de distribución, otras 14 e...

Centrocestus formosanus (Opisthorchiida: Heterophyidae como causa de muerte de alevines de tilapia gris Oreochromis niloticus (Perciforme: Cichlidae en el Pacífico seco de Costa Rica

Directory of Open Access Journals (Sweden)

Donald Arguedas Cortés

2010-12-01

Full Text Available Centrocestus formosanus es un parásito trematodo zoonótico originario de Asia asociado con muertes de peces principalmente de cultivo. 907 moluscos provenientes de estanques sembrados con tilapias, seleccionados uno por provincia fueron identificados al nivel taxonómico especifico. Se identificaron cuatro gastrópodos y un bivalvo: M. tuberculata, M. turricula, P. flagellata, H. cubensis y A. luteola. Se reporta, por primera vez, la presencia de dos especies de moluscos en Costa Rica. Se identificaron siete morfotipos de cercarias parasitando las cinco especies de moluscos encontradas. En la segunda exposición experimental se demostró que el morfotipo parapleurolofocercus encontrado en M. tuberculata concuerda con el hallazgo de C. formosanus en alevines de tilapia, después del examen clínico, anatomopatológico y parasitológico realizado a los alevines expuestos. Las metacercarias fueron extraídas del quiste utilizando microagujas y micropinzas lavadas en solución salina fisiológica (0.65%, fijadas en formol caliente al 4% y después esquematizadas con una cámara clara adaptada a un microscopio fotónico, estimándose una abundancia e intensidad media de 1018-1027 digeneos por branquia en cada pez parasitado, determinándose así el hospedador intermediario primario y secundario del parásito. En el presente trabajo se reporta por primera vez Centrocestus formosanus en Costa Rica.Centrocestus formosanus (Opisthorchiida: Heterophyidae as a cause of death in gray tilapia fry Oreochromis niloticus (Perciforme: Cichlidae in the dry Pacific of Costa Rica. Centrocestus formosanus is a zoonotic trematode from Asia and has been mainly associated as cause of death of cultured fish. To identify pathogen trematode species in tilapia fry (Oreochromis niloticus and to determine mollusks hosting these parasites, freshwater mollusks were collected from tilapia cultured ponds and experimental infections were carried out with tilapia fries and

Otimização do processo de depuração de moluscos bivalves

OpenAIRE

Correia, Maria Helena Oliveira Casimiro

2016-01-01

A contaminação microbiológica de moluscos bivalves constitui uma das principais preocupações inerentes à segurança alimentar desta importante fonte de receitas para a economia portuguesa. Os bivalves capturados ou produzidos em zonas estuarinas ou lagunares devem passar por um processo de depuração, para redução dos níveis de contaminação microbiológica, antes da sua comercialização. Este trabalho teve como principal objetivo o desenvolvimento de sistemas modulares de dep...

Relação entre a patogenicidade do Schistoma mansoni em camundongos e a susceptibilidade do molusco vetor: II. Número de ovos nas fezes e número e tamanho dos granulomas nas vísceras Relationship between the pathogenicity of Schistoma mansoni in mice and the susceptibility of the vector mollusc: II. Number of eggs in the feces and number and size of granulomas in the visceras

Directory of Open Access Journals (Sweden)

Eliana Maria Zanotti-Magalhães

1993-12-01

Full Text Available Estudou-se a influência da susceptibilidade de moluscos vetores do S. mansoni no desenvolvimento da patogenicidade do trematódeo no hospedeiro definitivo. Foram utilizadas progênies de moluscos Biomphalaria tenagophila e Biomphalaria glabrata selecionadas para o caráter susceptibilidade ao S. mansoni das linhagens SJ e BH, respectivamente. Cercárias oriundas das gerações P, F1 F2, F3 e F4 foram usadas para a infecção de camundongos Swiss, que foram sacrificados oito semanas após a exposição às larvas. Por esta ocasião verificou-se o número de ovos nas fezes e o número de granulomas no fígado, baço e intestino. Avaliou-se também o tamanho das reações granulomatosas nestas vísceras. Concluiu-se que a maior susceptibilidade de B. tenagophila induziu a uma maior eliminação de ovos do parasita nas fezes. Verificou-se maior número de granulomas por área de tecido hepático em roedores infectados com cercárias oriundas de moluscos mais susceptíveis. Nos mesmos roedores, constatou-se relação inversa entre a área dos granulomas esplênicos, hepáticos e intestinais e a taxa de infecção dos moluscos que forneceram as cercárias para a infecção dos camundongos.The influence of the susceptibility of the vector snails of S. mansoni on the development of the pathogenicity of the worm to the host was studied. Off-spring of snails Biomphalaria glabrata and Biomphalaria tenagophila were used, selected with regard to the susceptibility to S. mansoni of the strains BH and SJ trait, respectively. Parenteral, F1,F2, F3 and F4 generation cercariae were used for the infection of Swiss mice, which were killed eight weeks after infection. The number of eggs in the feces and the number of granulomas in the liver, spleen and intestines were counted. The size of the granulomatous reactions was evaluated. The results led to the conclusion that greater susceptibility of B. tenagophila was associated with a larger egg production in the feces

Phytochemical characterization of the threatened specie Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi

Directory of Open Access Journals (Sweden)

Mabelkis Terry Rosabal

2016-04-01

Full Text Available Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi is commonly known as buffalo, represents an endemic subspecies and categorized as critical danger of extinction in Cuba. This work aimed to characterize the phytochemical composition of plants of F. caroliniana in two localities of the Matanzas province. The presence of secondary metabolites in leaf extracts was qualitatively analyzed and reductive and total sugars were quantified. The results indicated the presence of flavonoids, terpenes, steroids, saponins, tannins and anthraquinones in leaves that could be considered for further systematic studies and application in agriculture. The plants from the Ciénaga de Zapata showed contents of reducing sugars and totals higher than those obtained in the plants of Martí. These results provide information for the identification of characters of possible taxonomic and conservation value in this species.   Keywords: anthraquinons, extracts, swamp ash, steroids, tannins, terpens

Aislamiento e identificación de Vibrio parahaemolyticus O3: K6 en pescados y moluscos bivalvos procedentes de un mercado pesquero de Lima, Perú

Directory of Open Access Journals (Sweden)

Rocío Aliaga

2010-07-01

Full Text Available Objetivo: Determinar la presencia de Vibrio parahaemolyticus serotipo O3:K6 en pescados y moluscos bivalvos procedentes de un mercado pesquero de Lima. Material y Métodos: Se analizaron 254 muestras entre pescados y moluscos bivalvos siguiendo la técnica descrita por Yukiko Harakudo et al, que consta de un paso de enriquecimiento, siembra en medio cromogénico, evaluación de fermentación de glucosa y la prueba de tolerancia a sales. Las cepas identificadas como Vibrio parahaemolyticus fueron serotipificadas usando anticuerpos monoclonales y evaluadas en su potencial patogénico en medio de Wagatsuma. Resultados: Se aislaron 15 cepas de V. parahaemolyticus, 9(7,5% en pescados y 6(4,5% en moluscos bivalvos. Tres (20% presentaron fenómeno de Kanagawa positivo indicando la producción de la hemolisina termoestable directa (TDH. Una cepa TDH-positiva aislada en una muestra pescado fue serotipo O3:K6. Conclusiones: Vibrio parahaemolyticus se encuentra distribuido en los recursos hidrobiológicos estudiados con mayor frecuencia en pescados, a partir de los cuales se encontró el serovar O3:K6. Este es el primer reporte de la cepa pandémica O3:K6 de Vibrio parahaemolyticus aislada de fuente no humana en el Perú. (Rev Med Hered 2010;21:139-145.

Identificación de Yarrowia lipolytica (Ascomycota: Hemiascomycetes como contaminante en la obtención de amplificados del gen 28S rRNA de moluscos

Directory of Open Access Journals (Sweden)

Jenny Chirinos

2011-05-01

Full Text Available En el presente trabajo se identifica una secuencia de DNA no esperada proveniente de los amplificados del gen 28S rRNA de moluscos terrestres. Las extracciones de DNA se realizaron del tejido del pie de caracoles terrestres por el método del CTAB modificado. Las PCRs fueron llevadas a cabo con primers universales para el gen COI e iniciadores diseñados para moluscos, para el marcador 16S rRNA, 28S rRNA y la región ITS-2. Los tamaños aproximados de las bandas de los amplificados de moluscos fueron de 706 pb para el COI, 330 pb para el 16S rRNA, 900 pb para el ITS-2 y 583 pb para el 28S rRNA; un amplificado del último marcador fue de una longitud inesperada, ~340 pb. Las secuencias de DNA fueron comparadas con la base de datos del GenBank mediante el programa BLASTn y la muestra con la banda de tamaño inesperado resultó en un 100% de identidad y cobertura del 99% con el gen 26S rRNA de la levadura Yarrowia lipolytica. El análisis filogenético con Neighbour-Joining y los valores de divergencia confirmaron la identificación, proporcionando resultados que apoyan la ubicación taxonómica de la especie dentro del clado de los Hemiascomycetes.

La Historia de una especie del patrimonio holguinero: Escobaria cubensis (Cactaceae "el cactus enano". Primera parte

Directory of Open Access Journals (Sweden)

Alena Reyes Fornet

2010-01-01

Full Text Available Presenta una investigación sobre la historia taxonómica y estudios sobre la ecología del "cactus enano de Holguín", Escobaria cubensis (Britton & Rose Hunt, 1978 desde 1909 hasta 1990, elementos importantes, para la conservación y como contribución al conocimiento de la historia del patrimonio natural holguinero, con datos históricos sobre visitas de personalidades del mundo y Holguín. Se estudiaron 37 materiales correspondientes a notas de viajes, cartas y publicaciones. Se señala la posibilidad de que el colector, J. Shafer estuvo en dos zonas de distribución. Las contribuciones al conocimiento de su ecología hasta 1990 se basaron en la observación y descripción.

Presencia de moluscos tropicales de la provincia panameña en la costa central del Perú y su relación con los eventos "El Niño"

Directory of Open Access Journals (Sweden)

Carlos Paredes

2014-06-01

Full Text Available Se reporta el hallazgo de moluscos cuya distribución conocida se encuentra dentro de los límites de la Provincia Panameña, en diversas localidades de la Provincia Peruana entre los años 1972 y 1994, período en el que se presentaron varios eventos "El Niño". Fue posible determinar 15 especies de moluscos que ampliaron su distribución: Pteria stema, Orobitella peruviana, Cryptornya califomica, Cerithium (T stercusmuscarum, Malea ringens, Hexaplex brassica, Thais styllmanberryi, T (M. triangularis, T (T callaoensis, Acanthina brevidentata, Purpura pansa, Neorapana muricata, Anachis (C. nigricans, Cancellaria (C. decussata y C. (B. chrysostorna. Se postula una variabilidad en los límites de las provincias biogeográficas de la costa peruana, controlada por el ENSO.

Variabilidad temporal y espacial de moluscos de fondos blandos circalitorales de la Bahía de Málaga

OpenAIRE

Díaz, A. (Alfonso); Rueda, J.L. (José Luis); Marina-Ureña, P. (Pablo); Urra, J. (Javier); Bárcenas, P. (Patricia); Fernández-Salas, L.M. (Luis Miguel); López-González, N. (Nieves); Serna-Quintero, J.M. (José Miguel); Giráldez, A. (Ana); García-Jiménez, M.T. (María Teresa); Baro, J. (Jorge); Gallardo-Núñez, M. (Marina)

2014-01-01

La bahía de Málaga se localiza dentro en un punto caliente de biodiversidad, como es el mar de Alborán, y además representa una zona con importantes recursos pesqueros, tanto pelágicos como bentónico-demersales. La información sobre comunidades de fondos blandos circalitorales es hasta la fecha muy limitada tanto para esta bahía como para el Mar de Alborán. Por otro lado, los moluscos son importantes componentes de dichas comunidades e incluyen numerosas especies de interés pesquero. El prese...

Los moluscos y la contaminación: Una revisión Mollusks and pollution: A review

Directory of Open Access Journals (Sweden)

Erick Raúl Baqueiro-Cárdenas

2007-10-01

Full Text Available Los moluscos son un grupo megadiverso que en cuanto a número de especies sólo lo sobrepasan los insectos y los nemátodos; no así en cuanto a la diversidad de hábitos de vida y hábitats que ocupan. Las especies de moluscos se encuentran en los desiertos y en las zonas polares; en los trópicos y en las grandes profundidades oceánicas. Sin embargo, es en las lagunas litorales tropicales donde alcanzan su máxima diversidad y función; los hay desde consumidores primarios en las redes tróficas, tanto de herbívoros como de detritívoros, hasta depredadores de segundo nivel y parásitos especializados. Existen especies especializadas y especies oportunistas, lo que se manifiesta en diferentes respuestas a las modificaciones del hábitat y la contaminación. En esta contribución se analizan las respuestas que individuos o poblaciones de moluscos tienen al impacto de la contaminación, así como sus mecanismos etológicos y fisiológicos de adaptación o sobrevivencia. Tomando en consideración lo anterior, se plantea su aplicación como indicadores de contaminación, ya sea por la desaparición de especies estenobiónticas, el predominio de las euribiónticas o por su capacidad de acumular contaminantes cuando sus concentraciones no alcanzan dosis que impacten las poblaciones, bien en procesos de bioacumulación a lo largo del ciclo de vida del organismo o por biomagnificación a través de las cadenas tróficas o de los cambios fisiológicos producidos por la contaminación.Mollusks are a mega-diverse group, surpassed only by insects and nematodes in number of species, but not in diversity of life strategies and occupied habitats; they can be found from deserts to polar zones and from the highest mountain to the deepest ocean trench. But it is at tropical coastal lagoons where they find their maximum diversity and function; there are first order consumers in both herbivore and detritus food chains, to second order carnivores and specialized

Moluscos de los fondos de cascajo profundo de la isla de Alborán (Proyecto LIFE+ INDEMARES Alborán)

OpenAIRE

Gofas, Serge; Luque, Angel A.; Salas, Carmen; Templado, José; Pola, Marta; Urra, Javier; Brusa, Viviana S.; Verdes, Aida

2014-01-01

Durante el proyecto LIFE+ INDEMARES Alborán (2011-2013), se tomaron diez muestras mediante arte de arrastre (bou de vara) en los fondos de cascajo profundo que aparecen entre 80 y 200 m en la plataforma insular de la isla de Alborán. Estos fondos están formados por restos calcáreos biógenos (bioclastos). En las muestras se han encontrado un total de 2.713 ejemplares vivos de moluscos pertenecientes a 147 especies (2 solenogastros, 2 poliplacóforos, 97 gasterópodos, 45 bivalvos, 1 cefalópodo)....

Physa cubensis Pfeiffer, 1839 (Pulmonata: Physidae

Directory of Open Access Journals (Sweden)

W. Lobato Paraense

1987-03-01

Full Text Available A description of Physa cubensis Pfeiffer, 1839, based on 15 speciments collected in Havana, Cuba, is presented. The shell, measuring 9.0 x 4,8mm to 12.3 x 6.4mm, is ovate-oblong, thin, diaphanous, horncolored, shining. Spire elevated, broadly conical; protoconch distinct, roundish, reddish-brown. About five moderately shouldered, roundly convex whorls, penultimate whorl expanded; spiral striation subobsolete; growth line faint on the intermediate whorls, clearly visible on the body whorl, crowded here and there. Suture well impressed. Aperture elongated 2.05 - 2.67 (mean 2.27 times as long as the remaining length of the shell, narrow obovulate-lunate; upper half acute-angled, lower half oval, narrowly rounded at the base; outer lip sharp, inner lip completely closing the umbilical region; a thick callus on the parietal wall; columellar plait well marked. Ratios: shell width/shell length - 0.52-0.61 (mean 0.55; spire length/shell length = 0.27 - 0.33 (mean 0.31; aperture length/shell length = 0.67 - 0.73 (mean 0.69. Oral lappets laterally mucronate; foot spatulate with acuminate tail. Mantle relection with 6 - 8 short triangular dentations in the right lobe (columellar side and 4 - 6 in the left lobe (near the pneumostome. Renal tube tightly folded into a zigzag course. Ovotestis, ovispermiduct, seminal vesicle, oviduct, nidamental gland, uterus and vagina as in Physa marmorata (see Paraense, 1986, Mem. Inst. Oswaldo Cruz, 81: 459-469. Spermathecal body egg-shaped or pear-shaped; spermathecal ducta uniformly narrow with expanded base, a little longer than the body. Spermiduct, prostate and vas deferens as in P. marmorata (Paraense, loc. cit.. Penis wide proximally, narrowing gradually apicad; penial canal with subterminal outlet. Penial sheath following the width of the penis and ending up by a bulbous expansion somewhat narrower than the proximal portion. Penaial sheath/prepuce ration = 1,25 - 1,83 (mean 1.49. Prepuce much wider than the bulb of

COLONIZACIÓN DE MOLUSCOS Y CRUSTÁCEOS EN RAÍCES DE MANGLE ROJO EN UNA LAGUNA COSTERA DE LA PUNTA NORTE DEL GOLFO DE MORROSQUILLO

Directory of Open Access Journals (Sweden)

PRÜSMANN JOHANNA

2010-05-01

Full Text Available Se evaluaron la colonización y sucesión de moluscos y crustáceos en un sustrato de raíces de mangle en tres estaciones en la ciénaga La Boquilla, Punta San Bernardo en la parte norte del Golfo de Morrosquillo. Para el seguimiento del proceso de colonización se ubicaron tres sitios en las márgenes occidental, norte y oriental, y se fijaron en cada estación seis raíces aéreas deshojadas de Rhizophora mangle. Luego de 76 y 200 días de exposición, se retiraron tres raíces de cada sitio y se identificaron los organismos por morfoespecie. Después de 200 días de exposición, se determinaron 19 especies de moluscos y cinco de crustáceos. El anfípodo Corophium sp. y el bivalvo Brachidontes exustus fueron las especies mas numerosas y agruparon una fracción muy importante de la totalidad de los individuos recolectados. La mayoría de las especies encontradas son típicas de la fauna acompañante de las raíces de mangle en el Caribe colombiano.

Identificación fitoquímica de las hojas y ramas de la Helietta cubensis Monach-Moldenke, especie endémica de Cuba

Directory of Open Access Journals (Sweden)

Sandra del Castillo Ochoa

2004-04-01

Full Text Available Se describe el tamizaje fitoquímico preliminar de las hojas y ramas de la Helietta cubensis Monach -Moldenke, especie endémica cubana que crece en la cima de los mogotes de Pinar del Río. La detección de los metabolitos secundarios se realizó mediante reactivos de identificación específicos para cada familia de compuestos. En ambas partes de la especie se identificaron en alta abundancia flavonoides y lactonas/coumarinas; en baja concentración se detectaron triterpenos/esteroides, lípidos/aceites esenciales, saponinas y carotenos y no la presencia de aminas y alcaloides. Mediante el análisis por cromatografía de capa fina se pudo corroborar los resultados obtenidos en la identificación de alcaloides, flavonoides y coumarinas. En general, los resultados obtenidos fueron homogéneos para ambas partes de la planta, y constituyen el primer reporte de la composición química para esta especie.The preliminary phytochemical screening of the leaves and branches of Helietta cubensis Monach-Moldenke, a Cuban endemic species that grows in the hummocks of Pinar del Río is described. The detection of the secondary metabolites was carried out by reagents of identification that are specific for each family of compounds. A great number of flavonoids and lactones/coumarines was identified in both parts of the species. A low concentration of triterpenes/steroids, lipids/essential oils, saponins and carotenes was observed, whereas amines and alkaloids were not detected. The results obtained in the identification of alkaloids, flavonoids and coumarines were corroborated by thin layer chromatography. In general, the results attained were homogeneous for both parts of the plant and they are the first report about the chemical composition of this species.

RENDIMENTO DE CARCAÇA E COMPOSIÇÃO CENTESIMAL DO MÚSCULO DOS MOLUSCOS ESCARGOT (Achatina fulica) E ARUÁ (Pomacea lineata)

OpenAIRE

S. H. R. BARBOZA; P. F. ROMANELLI

2008-01-01

O presente trabalho teve como objetivo avaliar a composição corporal (rendimento de carcaça) e a composição centesimal do músculo dos moluscos escargot e aruá. As avaliações foram realizadas comparando-se 6 grupos de animais de pesos e idades diferentes (3 de escargot e 3 de aruá) com um grupo controle (escargot), animais estes com 4 meses de idade e peso entre 20 e ...

ESTUDO DO APROVEITAMENTO DAS VÍSCERAS DOS MOLUSCOS ESCARGOT (Achatina fulica) E ARUÁ (Pomacea lineata) PARA INCORPORAÇÃO EM RAÇÃO ANIMAL

OpenAIRE

S. E. R. BARBOZA; P. F. ROMANELLI

2008-01-01

O objetivo deste trabalho foi estudar o aproveitamento das vísceras - subprodutos, dos moluscos escargot e aruá. As vísceras foram processadas na forma de farinha e suas características físico-químicas (composição centesimal, cálcio, fósforo, digestibilidade em pepsina, índice de acidez) e microbiológicas (Salmonella sp) foram comparadas aos padrões de qualidades exi...

Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs Variação genética entre moluscos susceptíveis e não susceptíveis à infecção pelo Schistosoma através da análise do DNA polimórfico amplificado aleatóriamente (RAPDs

Directory of Open Access Journals (Sweden)

Abdel-Hamid Zaki ABDEL-HAMID

1999-09-01

Full Text Available Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers were used to amplify the extracted DNA by the polymerase chain reaction (PCR followed by polyacrylamide gel electrophoresis (PAGE and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.A susceptibilidade de moluscos à infecção por certos trematódeos e a sua capacidade como hospedeiro para o contínuo desenvolvimento é o problema mais deslumbrante nas relações parasita hospedeiro. O presente trabalho, focaliza nosso interesse na genética dos moluscos para determinar quais genes ou produtos gênicos são especificamente responsáveis pela susceptibilidade do molusco à infecção. DNA de alto peso molecular, foi extraído de ambos moluscos susceptíveis e não susceptíveis da espécie Biomphalaria tenagophila. Iniciadores aleatórios com 10 pares de bases foram usados na amplificação aleatória (RAPD de ambos os DNAs e análise por eletroforese em gel de poliacrilamida e coloração com prata. Os resultados mostram que a amplificação aleatória do DNA representa um eficiente caminho para a comparação dos genomas desde que marcadores moleculares foram detectados como variantes genéticos entre os moluscos susceptíveis e não susceptíveis.

Moluscos; anélidos y crustáceos asociados a las raíces de Rhizophora mangle linnaeus, en la región de Santa Marta, caribe colombiano Moluscos; anélidos y crustáceos asociados a las raíces de Rhizophora mangle Linnaeus, en la región de Santa Marta, caribe colombiano

Directory of Open Access Journals (Sweden)

Reyes Rosalba

1992-09-01

Full Text Available A qualitative and quantitative study of the community of macro invertebrates associated to the submerged stilt roots of the red mangrove, Rhizophora mangle Linnaeus, 1753, was carried out trimonthly between December 1988 and September 1989, in three stations at the Cienaga Grande de Santa Marta (CGSM and three at the Parque Nacional Natural Tayrona (PNNT, Bahia de Chengue, Bahia de Nenguange, Colombian Caribbean. 181 species were determined: 99 crustaceans, 50 molluscs and 32 annellids. Most of the 26.729 individuals counted were crustaceans (12.213 moluscs (11.635 and annellids (2.881. The lowest diversity and evenness values, and the highest dominance values were found at the CGSM, while the opposite occurred at the PNNT. Moreover, cluster analysis showed that at the CGSM temporal variations in community composition were greater than spatial ones, while at the PNNT spatial differences were stronger. Other factors that could be importantin determinig community structure were detected, such as vecinity to other ecosystems and/or species- specific biological aspects as adaptations to fluctuating conditions, reproductive acti vities, feeding habits and migration to protected and shaded habitats. Se realizó un estudio trimestral cualitativo y cuantitativo de la comunidad de moluscos, anélidos y crustáceos asociados a las raíces sumergidas del mangle rojo, Rhizophora mangle Linnaeus, entre diciembre de 1988 y septiembre de 1989, en tres estaciones en la Ciénaga Grande de Santa Marta (CGSM y tres en el Parque Nacional Natural Tayrona (PNNT, Bahía de Chengue y Bahía de Nenguange, Caribe colombiano. Se determinaron 181 especies: 99 crustáceos, 50 moluscos y 32 anélidos. En total se contaron 26.729 individuos: 12.213 crustáceos, 11.635 moluscos y 2.881 anélidos. Los valores más bajos de diversidad y equitatividad, y los mayores valores de dominancia, se encontraron en la CGSM, mientras que lo opuesto ocurrió en el PNNT. El análisis de

Estado del conocimiento de la durofagia en el registro fósil: interacción depredador-presa en moluscos marinos (Clases Gastropoda y Bivalvia

Directory of Open Access Journals (Sweden)

Catalina Gómez-Espinosa

2015-01-01

Full Text Available La depredación como un mecanismo evolutivo, de diversificación y biomineralización es un tópico de gran interés. Un tipo específico de depredación es la durofagia que se define como el hábito alimenticio de los animales que consumen organismos con un esqueleto duro mineralizado, ya sea concha o exoesqueleto. Los moluscos representan una fuente muy importante para examinar la depredación durófaga en el registro fósil debido a su distribución mundial, abundancia, buena preservación y a que habitan en una gran variedad de ambientes. En este trabajo se revisa el número de artículos publicados en revistas de circulación internacional que se enfocan en el tema de la durofagia y que tienen como potenciales presas a gasterópodos y bivalvos marinos fósiles. Se recuperaron y revisaron 101 artículos sobre este tema, enfocados en seis tipos de evidencia: perforación, reparación y fragmentación de la concha, mordidas, “punctures” y coprolitos. La mayoría de los ejemplos correspondieron a moluscos del Cenozoico. En general hay más registros en la zona tropical. Durante el Paleozoico, la mayoría de las veces, no se identificó el potencial depredador; esta tendencia continuó en el Mesozoico pero se reconoció la depredación de gasterópodos y bivalvos por parte de gasterópodos carnívoros, artrópodos, peces y reptiles. Durante el Cenozoico dominó la depredación por parte de gasterópodos natícidos y murícidos y se reconoció también la depredación por parte de ar trópodos, peces y mamíferos.

Malacología Latinoamericana: Moluscos de agua dulce de Argentina

Directory of Open Access Journals (Sweden)

Alejandra Rumi

2008-03-01

Full Text Available Se presenta un estado de situación y una lista actualizada y comentada sobre las especies de moluscos de agua dulce de la República Argentina. Se aborda en Gastropoda y Bivalvia la distribución a nivel de familias; las entidades endémicas, exóticas, invasoras y de importancia sanitaria. Los moluscos relacionados a la cuenca del Plata presentan la mayor riqueza específica. Base de datos: 4 500 registros relevados de las tres colecciones más importantes de la Argentina: MLP, MACN y FML. Además, se incluye información de recolecciones actuales y localidades citadas por otros autores. Hasta el presente han sido descritas 166 especies. De ellas 101 pertenecen a 10 familias de Gastropoda y 65 a 7 de Bivalvia. Las familias que presentan mayor riqueza específica son Lithoglyphidae (22 y Sphaeriidae (25, respectivamente. Sphaeriidae, Cochliopidae, Chilinidae y Lymnaeidae se distribuyen prácticamente en todo el país. Erodonidae y Solecurtidae se registran en ambientes mixohalinos de la provincia de Buenos Aires. Thiaridae y Glacidorbiidae presentan una distribución muy restringida. Especies endémicas de la Argentina: Gastropoda: Ampullariidae (1, Cochliopidae (10, Lithoglyphidae (11, Thiariidae (3, Chilinidae (11, Lymnaeidae (2 y Physidae (2?; Bivalvia: Hyriidae (1?; Etheriidae (1? y Sphaeriidae (10. Especies de interés sanitario: propagadoras de: Esquistosomiasis, Biomphalaria peregrina, B. straminea y B. tenagophila (Planorbidae; Fasciolasis, Lymnaea viatrix y L. columnella (Lymnaeidae; y dermatitis esquistosómicas, Chilina gibbosa y C. fluminea (Chilinidae. Especies de origen asiático: Corbicula fluminea (Corbiculidae y Limnoperna fortunei (Mytilidae. Es prioritaria la formación de áreas protegidas para la conservación de especies endémicas, especialmente de la Mesopotamia Argentina.Latin American Malacology. Freshwater Mollusks from Argentina. A report and an updated list with comments on the species of freshwater molluscs of

Dinámica de la microflora contaminante en el molusco Aulacomya ater choro crudo y procesado en cebiche: 1.- anallsis cuantitativo.

Directory of Open Access Journals (Sweden)

Juana María Coha

2014-06-01

Full Text Available Se ha determinado, cuantitativamente, presencia de organismos Coliformes y Enterococos en el molusco Aulacomya ater "choro", como índice de contaminación entérica humana, en cada etapa de su preparación hasta "cebiche". Se han pracesado 1,152 especímenes de mercados de Lima y Callao. Los resultados reportan mayores promedios de contaminación para ambos grupos m'crobianos, en choros crudos (etapa a, de mercados ubicados en zonas de menor higiene y mayor población. La temperatura ambiental en meses de verano, demuestra gran incremento de esta microflora. La temperatura de cocción de la fracción previa al "cebiche" (etapa b, efímina totalmente los contaminantes, reapareciendo Coliformes en éste (etapa el, por los aditivos. El jugo de limón no actuó como bactericida eficaz.

Metabolitos secundarios, letalidad y actividad antimicrobiana de los extractos de tres corales y tres moluscos marinos de Sucre, Venezuela

Directory of Open Access Journals (Sweden)

Gabriel Ordaz

2010-06-01

Full Text Available A los extractos crudos de los octocorales Eunicea sp., Muricea sp. y Pseudopterogorgia acerosa y de los moluscos Pteria colymbus, Phylonotus pomum y Chicoreus brevifrons, se les realizaron pruebas químicas, las cuales evidenciaron en todos ellos, la presencia de metabolitos secundarios como alcaloides, esteroles insaturados y triterpenos pentacíclicos. Sólo se detectaron sesquiterpenlactonas, saponinas, taninos, glicósidos cianogénicos y glicósidos cardiotónicos en algunos de los extractos de los octocorales, lo cual sugiere que la biosíntesis de estos metabolitos es propia de este grupo de organismos. Asimismo, se evaluó la actividad letal y antimicrobiana de los extractos de los octocorales y moluscos. En el bioensayo de letalidad, todos los extractos resultaron letales frente al crustáceo Artemia salina (CL50Secondary metabolites, lethality and antimicrobial activity of extracts from three corals and three marine mollusks from Sucre, Venezuela. The study of biochemical activity of extracts obtained from marine organisms is gaining interest as some have proved to have efficient health or industrial applications. To evaluate lethality and antimicrobial activities, some chemical tests were performed on crude extracts of the octocorals Eunicea sp., Muricea sp. and Pseudopterogorgia acerosa and the mollusks Pteria colymbus, Phyllonotus pomum and Chicoreus brevifrons, collected in Venezuelan waters. The presence of secondary metabolites like alkaloids, unsaturated sterols and pentacyclic triterpenes in all invertebrates, was evidenced. Additionally, sesquiterpenlactones, saponins, tannins, cyanogenic and cardiotonic glycosides were also detected in some octocoral extracts, suggesting that biosynthesis of these metabolites is typical in this group. From the lethality bioassays, all extracts resulted lethal to Artemia salina (LC50<1.000μg/ml with an increased of lethal activity with exposition time. P. pomum extract showed the highest

Is there redundancy in bioengineering for molluscan assemblages on the rocky shores of central Chile? ¿Existe redundancia en la bioingeniería de los ensambles de moluscos de las costas rocosas de Chile central?

Directory of Open Access Journals (Sweden)

BRENDAN P KELAHER

2007-06-01

través de sus propias estructuras físicas e incrementan la diversidad local. En costas rocosas existen grandes solapamientos en la composición de las comunidades asociadas a bioingenieros que forman habitats frondosos (algas o mitílidos. Nosotros investigamos la potencial redundancia en la provisión de este tipo de habitat comparando ensambles faunísticos asociados a mantos de Perumytilus purpuratus y frondas de Corallina officinalis var. chilenis, Gelidium chilense y Gastroclonium cylindricum. En tres oportunidades, entre septiembre de 2003 y enero de 2004, muestreamos ensambles de moluscos asociados a cada uno de estos bioingenieros, en alturas de mareas similares en dos áreas rocosas de Chile central. De las 31 especies de moluscos identificados, 30 fueron encontrados en Corallina y 19-22 fueron identificados en los otros habitat. El conjunto de especies asociado a cada bioingeniero se sobrepone ampliamente, demostrando el potencial de redundancia en la provisión de habitat y poca especificidad de habitat. Sin embargo, análisis multivariados y univariados mostraron que los bioingenieros, con excepción de Gastroclonium, contenían un ensamble de moluscos único en al menos uno de los periodos de muestreo, ya sea en la variación en la frecuencia de ocurrencia, riqueza y abundancia total. Estudios recientes han destacado diversos procesos antropogénicos y naturales que influencian directamente la diversidad y composición de especies en bioingenieros de costas rocosas. Se demuestra que para la costa de Chile central la pérdida de cualquier de los bioingenieros analizados no alteraría sustancialmente el conjunto total de especies de moluscos, alojados en ellos. Sin embargo, la pérdida de cualquier bioingeniero, excepto Gastroclonium, resultaría en una disminución local de la biodiversidad debido a que cada uno de los ensambles de moluscos en Perumytilus, Corallina y Gelidium, contiene una estructura comunitaria significativamente diferente, en al menos

Análisis de endemismo de moluscos dulceacuícolas de Chile Endemism analysis of Chilean freshwater mollusks

Directory of Open Access Journals (Sweden)

CARMEN FUENTEALBA

2010-06-01

Full Text Available La diversidad geológica y climática de Chile continental permite la diferenciación de una gran variedad de ecosistemas terrestres y acuáticos. La evidencia de los actuales patrones de distribución de especies dulceacuícolas sugiere en gran medida una relación con las glaciaciones del Pleistoceno y algunos eventos tectónicos postglaciales que afectaron la hidrografía del país. Las especies de moluscos dulceacuícolas en Chile, a diferencia de las especies marinas, han sido escasamente valoradas, a pesar del papel que cumple un importante número de ellas en los ecosistemas. Actualmente no existen estudios biogeográficos que permitan establecer patrones distribucionales y los procesos que los condicionaron. Un análisis de parsimonia de endemismos (PAE y de riqueza de cinco zonas hidrográficas, basado en 75 especies de moluscos dulceacuícolas, sugiere la existencia de tres áreas biogeográficas: Norte (entre las latitudes 17°-33° S, Centro-Sur (33°-44° S y Sur (44°-56° S. La zona hidrográfica V (44°-56° S, incluida en el área Sur, posee el mayor porcentaje de endemismo (75 %, a diferencia de la zona hidrográfica III (17°-26° S, incluida en el área Centro-Norte, la cual registró el valor más bajo (42 %.The Chilean geological and climatic diversity allows the differentiation of a great variety of terrestrial and aquatic ecosystems. Evidence provided by distributional patterns of freshwater species suggests a correspondence with Pleistocene glaciations, and some post-glacial tectonic events that affected the hydrography of the country. The species of freshwater Chilean mollusks, unlike the marine species, have been undervalued. Currently there are no biogeographic studies that would allow identifying distribution patterns and the possible processes that shaped them. A parsimony analysis of endemicity (PAE and the richness of five hidrographic zones, based on 75 freshwater mollusk species, suggests the existence of three

Ocorrência de linhagens humana e silvestre de Schistosoma mansoni, na pré-amazônia: I - estudo em moluscos Occurrence of wild and human strains of Schistosoma mansoni in lower Amazonia: I - study in moluscs

Directory of Open Access Journals (Sweden)

Othon de Carvalho Bastos

1982-10-01

Full Text Available Foram isoladas na região da Baixada Maranhense (Brasil, linhagens humana (H e silvestre(S de Schistosoma mansoni a partir de miracídios eclodidos de ovos encontrados em fezes de doentes humanos autóctones da Região e de fígados de roedores silvestres naturalmente infectados. Biomphalaria glabrata, descentes de caramujos coletados no campo, foram expostos, isoladamente, aos miracídios H e S, mantidos isolados em moluscário e observados durante 100 dias. Moluscos normais foram mantidos nas mesmas condições de ambiente em que foram submetidos os infectados e tomados como controle da experiência. Foram anotados os indices de infecção dos moluscos, as datas da eliminação de cercárias, quantidade de larvas eliminadas e mortalidade dos moluscos. Os dados sugeriram melhor adaptação do esquistossomo da linhagem H à B. glabrata. A linhagem S, por sua vez, foi três vezes mais virulenta do que a linhagem H. Estes dados foram comparados com os encontrados na literatura especializada e verificado diversidades nos comportamentos parasitológicos das linhagens em estudo, quando comparados com os encontrados nas linhagens H e S oriundas do Vale do Rio Paraíba do Sul, no Estado de São Paulo (Brasil.The wild (W and human (H strains of Schistosoma mansoni were isolated in the Lowland Region of the Maranhão State (Brazil. The snail progenies from Biomphalaria glabrata collected from that region were exposed to the W miracidia, obtained from livers of wild rodents, and H miracidia from eggs in human stools. A control gruop of normal snails was kept in the same conditions as the infected one. The date of the elimination of cercariae, the quantity of eliminated larvae, the infection index of the moluscs and the mortality rate of the snails were recorded. These data suggested better adaptation of the H strain to B. glabrata. The W strain presented three times more virulence to snails than the H strain. These results were compared with published

Abundancia y riqueza de moluscos y crustáceos asociados a las raíces sumergidas del mangle rojo (Rhizophora mangle en la laguna de Bocaripo, Sucre, Venezuela

Directory of Open Access Journals (Sweden)

Jennellis Cedeño

2010-10-01

Full Text Available Las raíces de mangle son un importante hábitat para muchas especies. Se estudió la abundancia y riqueza de moluscos y crustáceos asociadas a las raíces sumergidas de Rhizophora mangle. Las muestras fueron recolectadas entre febrero 2005 y enero 2006, en la laguna de Bocaripo, costa norte del estado Sucre, Venezuela. Se establecieron cinco estaciones en la laguna; al azar en cada estación se escogieron dos raíces de mangle, fueron introducidas en bolsas plásticas; los organismos fueron obtenidos de la raíz raspando la superficie con un cuchillo, luego fueron separados y fijados en formalina al 10% para su posterior identificación. Se recolectaron 1 092 especimenes de moluscos, distribuidos en dos clases: Bivalvia y Gastropoda. La clase Bivalvia fue la más abundante con 943 individuos. La familia más representativa fue Mytilidae con 6 especies, siendo Musculus lateralis la especie dominante. Los crustáceos estuvieron representados por 372 organismos, pertenecientes a la clase Malacostraca, donde Panopeus herbstii (169 ind. fue la especie más abundante. Las familias Panopeidae, Porcellanidae y Majidae presentaron el mayor número de especies. La máxima abundancia se encontró en febrero (224 ind. con una riqueza de 25 especies y la mínima en noviembre (45 ind. con 12. Las estaciones 1 y 5 presentaron la mayor abundancia y riqueza de organismos, lo cual pudiera estar relacionado con condiciones ambientales favorables, como la mayor disponibilidad de microhábitats y oferta alimenticia; por el contrario la estación 4, presentó un ambiente más inhóspito, debido a los altos valores en la salinidad y temperatura, lo cual contribuye con la menor abundancia y riqueza de las especies presentes.

Analysis of microsatellites from the transcriptome of downy mildew pathogens and their application for characterization of Pseudoperonospora populations

Directory of Open Access Journals (Sweden)

Emma C. Wallace

2017-05-01

Full Text Available Downy mildew pathogens affect several economically important crops worldwide but, due to their obligate nature, few genetic resources are available for genomic and population analyses. Draft genomes for emergent downy mildew pathogens such as the oomycete Pseudoperonospora cubensis, causal agent of cucurbit downy mildew, have been published and can be used to perform comparative genomic analysis and develop tools such as microsatellites to characterize pathogen population structure. We used bioinformatics to identify 2,738 microsatellites in the P. cubensis predicted transcriptome and evaluate them for transferability to the hop downy mildew pathogen, Pseudoperonospora humuli, since no draft genome is available for this species. We also compared the microsatellite repertoire of P. cubensis to that of the model organism Hyaloperonospora arabidopsidis, which causes downy mildew in Arabidopsis. Although trends in frequency of motif-type were similar, the percentage of SSRs identified from P. cubensis transcripts differed significantly from H. arabidopsidis. The majority of a subset of microsatellites selected for laboratory validation (92% produced a product in P. cubensis isolates, and 83 microsatellites demonstrated transferability to P. humuli. Eleven microsatellites were found to be polymorphic and consistently amplified in P. cubensis isolates. Analysis of Pseudoperonospora isolates from diverse hosts and locations revealed higher diversity in P. cubensis compared to P. humuli isolates. These microsatellites will be useful in efforts to better understand relationships within Pseudoperonospora species and P. cubensis on a population level.

Síntesis de los estudios sobre moluscos continentales neógenos del sector septentrional de la Depresión de Teruel: período 1775-1998

Directory of Open Access Journals (Sweden)

Robles, F.

2006-12-01

Full Text Available The relevant information on the fossil record of the Neogene molluscs of the north of the Teruel Basin in the period between the years 1775-1998 is compiled and analyzed. First, the total number of different taxa mentioned in every paper is counted, second only the number of specific references is counted. The last references are divided into three categories called: new references, new species and repeated references. Apart from the information contained in every paper, the number of taxa contemplated, and the typology of the specific references, it is proposed a classification of the studies on neogene molluscs of this area in six stages: first (1775-1849, second (1849-1910, third (1910-1936, fourth (1936-1962, fifth (1962-1991 and sixth (1991-1998.Se recopila y analiza la información que se considera más relevante y se encuentra contenida en los estudios realizados sobre el registro fósil de los moluscos neógenos del sector septentrional de la Depresión de Teruel en el período comprendido entre los años 1775 y 1998. Se contabilizan, por una parte, el número total de taxones diferentes mencionados en cada trabajo y, por otra, sólo el número de citas efectuadas a nivel de especie en cada uno de ellos. Estas últimas se organizan en tres categorías que reciben el nombre de citas nuevas, especies nuevas y citas repetidas. Se propone, a partir de la información contenida en cada trabajo, el número de taxones contemplados, y la tipología de sus citas específicas, una clasificación de los estudios sobre moluscos neógenos de esta área en seis etapas: primera (1775-1849, segunda (1849-1910, tercera (1910 1936, cuarta (1936-1962, quinta (1962-1991 y sexta (1991-1998.

Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

Directory of Open Access Journals (Sweden)

José Ángel Bautista Cotorruelo

2008-12-01

Full Text Available The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de la Región de Murcia a telephone call from the Epidemiology Service, which reported the existence of about 12-15 cases of children affected by Molluscum contagiosum. In addition, they indicated us that the suspicions fell on the Municipal Pool Cover Alhama de Murcia. Immediately we contacted the responsible staff and we send them a protocol developed with information from several sources. The analysis of articles used for water activities showed absence of Molluscum contagiosum. We selected "absence of molds and yeasts” as indicator. All this coincided with the disappearance of the cases. Months later, in March 2009 we detected new cases of children affected in another pool in the town of Alcantarilla. Due to the success of the methodology used in the earlier incident we performed the same actions and we obtained the same results. The protocol developed by this Service is effective to avoid the occurrence of more cases. We propose the “absence of molds and yeasts” as an indicator to evaluate the presence of Molluscum contagiosum. Coinciding with the update of the rules of public swimming pools in our Region we have introduced an article that indicates that the objects used for water activities must be disinfected after each use.El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso

Moluscos asociados a las raíces sumergidas del mangle rojo Rhizophora mangle, en el Golfo de Santa Fe, Estado Sucre, Venezuela

Directory of Open Access Journals (Sweden)

B. Márquez

2002-12-01

Full Text Available Se realizó un estudio mensual cualitativo y cuantitativo de la comunidad de moluscos asociados a las raíces sumergidas del mangle rojo, Rhizophora mangle, entre octubre de 1998 y septiembre de 1999, en seis estaciones del Golfo de Santa Fe (Estado Sucre, Venezuela. Se colectaron e identificaron un total de 4 704 individuos pertenecientes a 45 especies de moluscos (22 gasterópodos, 15 bivalvos y 8 polyplacóforos. Las especies más abundantes fueron: Crassostrea rhizophorae, Isognomon bicolor L alatus y Brachidontes exustus. Los valores más altos de diversidad y equitabilidad, y los menores valores de dominancia, se encontraron en las estaciones tres y cuatro, mientras que lo opuesto ocurrió en las estaciones uno y dos. El análisis de afinidad mostró que en las cinco primeras estaciones las variaciones espaciales en la composición de la comunidad son mayores que las variaciones temporales, mientras que en la estación seis priman las diferencias temporales. Se encontraron factores que podrían ser importantes para determinar la estructura de la comunidad, como vecindad a otros ecosistemas y/6 aspectos biológicos específicos de las especies como adaptaciones a condiciones fluctuantes, hábitos alimenticios y migración en busca de ambientes sombreados y protegidos.A qualitative and quantitative monthly study of the mollusks community associated to the submered roots of the red mangrove, Rhizophora mangle (L., between October of 1998 and September of 1999, in six stations of the Gulf of Santa Fe. (Suere State, Venezuela. Were collected 4 704 specimens, 45 species of mollusks were identified (22 gastropods, 15 bivalves and 8 chitons. The most abundant species were: Crassostrea rhizophorae, Isognomon bicolor, L alatus and Brachidontes exustus. The highest values in diversity and evenness, and the smallest dominant values, were in the stations three and four, while the opposed happened in the stations one and two. The analysis of likeness

Lesões molusco-símiles em paciente com esporotricose Molluscum-like lesions in a patient with sporotrichosis

Directory of Open Access Journals (Sweden)

Regina Casz Schechtman

2011-12-01

Full Text Available Esporotricose é uma infecção fúngica subcutânea, adquirida por inoculação direta, causada pelo Sporothrix schenckii. Embora a apresentação clássica linfocutânea represente a maioria dos casos, as formas clínicas atípicas e graves têm aumentado em ocorrência. Esporotricose sistêmica e esporotricose cutânea disseminada são variantes raras, usualmente associadas à imunodeficiência celular ou a estados debilitantes. Relatamos o primeiro caso na literatura de lesões molusco-símiles em esporotricose cutaneomucosa múltipla. Os exames micológico direto e histopatológico apresentavam-se ricos em células leveduriformes.Sporotrichosis is a subcutaneous fungal infection caused by Sporothrix schenckii and acquired by direct inoculation. Although the majority of cases consist of the classic lymphocutaneous presentation, the frequency of atypical and severe clinical forms of the disease has increased progressively. Systemic and disseminated cutaneous sporotrichosis constitute rare variants and such cases are generally associated with cellular immunodeficiency or debilitated states. The present paper describes the first published case of molluscum-like lesions in disseminated mucocutaneous sporotrichosis. Direct mycological examination and histopathology revealed numerous yeast cells.

Polyethylene mulch modifies greenhouse microclimate and reduces infection of phytophthora infestans in tomato and Pseudoperonospora cubensis in cucumber.

Science.gov (United States)

Shtienberg, D; Elad, Y; Bornstein, M; Ziv, G; Grava, A; Cohen, S

2010-01-01

The individual and joint effects of covering the soil with polyethylene mulch before planting and fungicides commonly used by organic growers on tomato late blight (caused by Phytophthora infestans) were studied in three experiments conducted from 2002 to 2005. Application of fungicides resulted in inconsistent and insufficient late blight suppression (control efficacy +/- standard error of 34.5 +/- 14.3%) but the polyethylene mulch resulted in consistent, effective, and highly significant suppression (control efficacy of 83.6 +/- 5.5%) of the disease. The combined effect of the two measures was additive. In a second set of three experiments carried out between 2004 and 2006, it was found that the type of polyethylene mulch used (bicolor aluminized, clear, or black) did not affect the efficacy of late blight suppression (control efficacy of 60.1 to 95.8%) and the differences in the effects among the different polyethylene mulches used were insignificant. Next, the ability of the mulch to suppress cucumber downy mildew (caused by Pseudoperonospora cubensis) was studied in four experiments carried out between 2006 and 2008. The mulch effectively suppressed cucumber downy mildew but the effect was less substantial (control efficacy of 34.9 +/- 4.8%) than that achieved for tomato late blight. The disease-suppressing effect of mulch appeared to come from a reduction in leaf wetness duration, because mulching led to reductions in both the frequency of nights when dew formed and the number of dew hours per night when it formed. Mulching also reduced relative humidity in the canopy, which may have reduced sporulation.

PROCESSAMENTO E AVALIAÇÃO SENSORIAL DA CARNE DOS MOLUSCOS ESCARGOT (Achatina fulica E ARUÁ (Pomacea lineata

Directory of Open Access Journals (Sweden)

S. H. R. BARBOZA

2009-01-01

Full Text Available

O presente trabalho foi desenvolvido com o objetivo de avaliar sensorialmente os produtos do processamento da carne dos moluscos escargot (Achatina fulica e aruá (Pomacea lineata. Foram realizados dois processamentos em conserva (enlatado: triturada e defumada. Na avaliação sensorial da carne triturada observou-se diferença significativa entre os produtos, favorável ao escargot com valor médio de aceitação igual a 5,35 e 4,76 para o aruá. Para os produtos elaborados defumados observou-se uma aceitação igual para as duas espécies (escargot = 4,82 e aruá = 4,49. Esses resultados de aceitação nos permitem admitir que os produtos são tecnicamente e sensorialmente viáveis para consumo (aceitação acima de 60% para os dois casos, mas com tendências ligeiramente favoráveis de preferência para os produtos elaborados com carne de escargot.

An introduction to vectors, vector operators and vector analysis

CERN Document Server

Joag, Pramod S

2016-01-01

Ideal for undergraduate and graduate students of science and engineering, this book covers fundamental concepts of vectors and their applications in a single volume. The first unit deals with basic formulation, both conceptual and theoretical. It discusses applications of algebraic operations, Levi-Civita notation, and curvilinear coordinate systems like spherical polar and parabolic systems and structures, and analytical geometry of curves and surfaces. The second unit delves into the algebra of operators and their types and also explains the equivalence between the algebra of vector operators and the algebra of matrices. Formulation of eigen vectors and eigen values of a linear vector operator are elaborated using vector algebra. The third unit deals with vector analysis, discussing vector valued functions of a scalar variable and functions of vector argument (both scalar valued and vector valued), thus covering both the scalar vector fields and vector integration.

El fenómeno 'El Niño' y los moluscos de la Costa peruana

Directory of Open Access Journals (Sweden)

1993-01-01

Full Text Available LE PHÉNOMÈNE 'EL NIÑO' ET LES MOLLUSQUES DE LA CÔTE PÉRUVIENNE. Parmi les bio-indicateurs du phénomène El Niño, les mollusques littoraux présentent l'avantage de posséder un test calcaire susceptible d'être préservé aussi bien dans des amas coquilliers d'origine anthropique que dans des dépôts géologiques naturels. Du fait de la répartition des provinces zoogéographiques sur la côte péruvienne, et en raison des effets directs des anomalies océano-climatiques El Niño dans la région, il est donc logique de supposer que les coquilles de mollusques sub-actuelles ou fossiles puissent jouer un rôle important dans la reconstitution d'événements El Niño du passé. Dans cette optique, ont été analysés les indices de présence/absence de certaines espèces de bivalves et de gastéropodes dans des dépôts archéologiques et géologiques de la côte péruvienne, à la lumière de quelques observations menées lors des épisodes récents de 1982-1983 et 1986-1987. Cette récapitulation des données relatives aux épisodes El Niño des dernières années et aux enregistrements possibles des événements plus anciens, montre qu'il reste beaucoup à apprendre sur la dynamique du peuplement et l'écologie des mollusques en réponse à l'anomalie océanographique, et qu'une certaine prudence est de mise lorsque l'on souhaite reconstituer ce type d'anomalies dans le passé. Dans quelques cas, néanmoins, il est envisagé que des conditions océanographiques de type El Niño aient pu permettre, à l'Holocène comme durant certains interglaciaires du Pléistocène, le transport de larves d'organismes provenant de la Province Panaméenne, ou de la Zone de Transition de Paita, jusqu'aux côtes du centre et du sud du Pérou (Province Péruvienne. Entre otros bioindicadores del fenómeno El Niño, los moluscos litorales presentan la ventaja de tener un esqueleto carbonatado que suele preservarse tanto en conchales de origen antr

Composición, distribución y abundancia de larvas de moluscos gastrópodos en el sur de Quintana Roo, México y norte de Belice

Directory of Open Access Journals (Sweden)

J Oliva Rivera

2000-12-01

Full Text Available Para conocer la composición, abundancia y distribución de larvas de gastrópodos, se realizaron muestreos mensuales de abril a diciembre de 1996 en el sur de Quintana Roo, México y norte de Belice. Las recolectas se hicieron en seis sitios de Banco Chinchorro, cuatro de la costa sur y seis en Hol-Chan, Belice. Las recolectas fueron hechas entre las 10 y 20 hrs, se bombearon 2.5 m³ de agua de mar por recolecta en un tiempo de diez minutos, filtrando a los organismos en una malla de 202 µm. Se identificaron un total de 27 especies de moluscos, las especies de mayor abundancia y de más amplia distribución en cada zona fueron: en la costa sur Rissoina sp. 1, Limacina sp. 1 y Natica sp., en Banco Chinchorro, Limacina sp. 1, Creseis acicula, Cerithiopsis hero y Rissoina sp. 1 y en Hol-Chan, Limacina sp. 2, Alaba incerta y Rissoina sp. 1. En general la mayor abundancia de moluscos se presentó en la época de lluvias. Aparentemente la presencia de corrientes y vientos fuertes y otros factores biológicos como el alimento, controlan la distribución y abundancia de las larvas.ha.To know the composition, abundance and distribution of gastropod larvae, monthly samplings were carried out in the south of Quintana Roo, Mexico and north of Belize, from April to December, 1996. Collections were made in six sites at Chinchorro Bank, four in the South Coast and six at Hol-Chan, Belize, between the 10 and 20 hrs. At each station 2.5 m_ of seawater were pumped through a 202 µm mesh; 27 species were identified. The most abundant species were: South Coast, Rissoina sp. 1., Limacina sp. 1 and Natica sp. 1, Chinchorro Bank, Limacina sp. 1, Creseis acicula, Cerithiopsis hero and Rissoina sp.1 and Hol-Chan, Limacina sp.2, Alaba incerta and Rissoina sp.1. The highest abundance was in rainy season. Apparently the presence of winds, coastal currents and food availability, control the distribution and abundance of larvae.

Una breve historia de la colección de moluscos del Museo Nacional de Ciencias Naturales de Madrid con especial referencia a la colección malacológica de Alí Bey y Simón de Rojas Clemente

OpenAIRE

Bragado, María Dolores; Andrés, Javier de; Araujo, Rafael

2017-01-01

Se recopilan todas las entradas de material malacológico en las colecciones del MNCN desde su fundación como Real Gabinete de Historia Natural en 1771 hasta 1935. Dentro de este estudio se hace especial referencia a la colección de moluscos que Manuel Godoy (1767-1851), el Príncipe de la Paz, depositó en 1804 en el Real Gabinete de Historia Natural. Esta colección, originalmente compuesta por vertebrados, invertebrados, fósiles, minerales y plantas, le fue regalada a Godoy por Domingo Badía i...

Los moluscos de la ofrenda 107 del Templo Mayor de Tenochtitlan The mollusks of the offering 107 of the Great Temple of Tenochtitlan

Directory of Open Access Journals (Sweden)

Norma Valentín-Maldonado

2007-10-01

Full Text Available El propósito de este trabajo es dar a conocer la identificación biológica de las especies de moluscos encontradas en la ofrenda 107, que fue depositada en la séptima etapa constructiva del Templo Mayor de Tenochtitlan (1502-1521. La identificación se realizó por medio de la bibliografía especializada, y en el caso de algunos ejemplares por comparación directa con los de la colección malacológica de referencia del Laboratorio M. en C. Ticul Álvarez Solórzano. Se identificaron 246 ejemplares de moluscos marinos; 191 pertenecen a la clase Gastropoda (78% y 55 a la Bivalvia (22%. El número más frecuente de especies proviene de la provincia caribeña, siendo su hábitat principal las playas arenosas y las costas rocosas. Los desgastes y fracturas observadas en la mayoría de los esqueletos calcáreos de animales ya muertos, indican que fueron recolectados en las playas; por otro lado, el buen estado de preservación de algunos de ellos sugiere que se capturaron vivos, y en ciertos casos mediante buceo. A través de este estudio ha sido posible obtener datos, como la procedencia, el hábitat, la coloración natural y la selectividad de las diferentes especies identificadas, los cuales contribuyen al conocimiento de aspectos económicos e ideológicos de la cultura mexica.The purpose of this work is to report the identifications of the species of mollusks found in offering 107, which was buried in the seventh stage of the construction of the Great Temple of Tenochtitlan (1502-1521. This was done by direct comparison with specimens in the malacological reference collection of the Ticul Álvarez Solorzano Laboratory and the literature. The 246 marine individuals belonging to two classes were identified; 191 belonging to the Gastropoda (78% and 55 to the Bivalvia (22%. The largest number of species came from the Caribbean Province, with species from sandy beaches and rocky coasts being most common. The abrasions and fractures observed in

Moluscos gasterópodos terrestres como indicadores de recuperación de bosque en los paisajes del Sur y Norcentro de Nicaragua

Directory of Open Access Journals (Sweden)

Marlon Sotelo

2015-10-01

Full Text Available Los moluscos terrestres son un grupo altamente diverso cuyo trabajo investigativo en Nicaragua ha sido mayoritariamente en la vertiente del Pacífico de Nicaragua. Evaluar el potencial de estas especies como indicadores de la perdida de la masa boscosa así como de su recuperación ayudará el impacto de las actividades humanas en esta biota de escasa movilidad. La colectas de conchas y especímenes fué realizada en bosques húmedos, nubosos y secos en los departamentos de Rivas y Jinotega en hábitats específicos dentro de la matrix del paisaje. Las identificaciones a posteriori fueron hechas para evitar el sesgo de identificaciones en especies de taxonomía debatible. Los hábitats forestales continuos mostraron valores mayores en biodiversidad que otros hábitats dentro de la matrix, mostrando que existe fidelidad de hábitat para la comunidad de caracoles en general. Esta alta fidelidad, muestra la importancia de este grupo cuando tratamos de obtener especies de fidelidad alta, ayudando a explicar cómo la perdida de bosque afecta a la fauna.

Los moluscos terrestres (Mollusca: Gastropoda de Costa Rica: clasificación, distribución y conservación

Directory of Open Access Journals (Sweden)

Zaidett Barrientos Llosa

2010-12-01

Full Text Available Los moluscos terrestres son un grupo muy poco estudiado a nivel mundial. Hay 183 especies reportadas para Costa Rica, 30% son endémicas y 7% posiblemente están extintas. Se espera que en el país haya alrededor de 400 especies, de más del 95% se desconoce su biología, ecología, distribución, genética y otros campos de estudio. En Costa Rica las familias con mayor número de especies son Spiraxidae, Orthalicidae y Subulinidae. No obstante, es posible que Euconulidae sea aun más diversa, pues habitan las zonas altas del país que es en donde menos trabajo se ha hecho. El estudio de regiones altas aumentará el porcentaje de endemismo. Los futuros trabajos malacológicos taxonómicos, biológicos y ecológicos deben considerar la poca movilidad de este grupo, su tendencia a formar especies nuevas en simpatría, la especificidad de requerimientos de microhábitat, el hermafroditismo, la alta tasa de evolución (10% por millón de años y la divergencia entre especies (2-30%. Para proteger adecuadamente la biodiversidad de la malacofauna costarricense, se requiere de estudios que determinen la distribución y abundancia de las especies y el efecto del uso de la tierra y del climático.

Estructura de la comunidad de moluscos y relaciones tróficas en el litoral rocoso del estado Sucre, Venezuela

Directory of Open Access Journals (Sweden)

Johanna Fernández

2006-12-01

Full Text Available Se analizó la estructura de la comunidad de moluscos y sus relaciones tróficas en seis localidades del litoral rocoso con diferentes grados de exposición al oleaje (área expuesta y área protegida, en el Estado Sucre, Venezuela. El muestreo se llevó a cabo durante el período de marzo 2003 a febrero 2004. La recolección del material biológico se realizó de forma manual con ayuda de una espátula, dentro de una cuadrícula de 0.25 m², estableciéndose tres zonas: supra, medio e infralitoral. Los organismos fueron preservados en frascos con formalina al 10% para su posterior análisis. En el laboratorio fueron identificados, contados, y pesados en una balanza de 0.001g de precisión. Se determinó la abundancia total de especies, biomasa, constancia específica y por medio de una revisión bibliográfica se le asignó a cada especie su categoría trófica, clasificándolos en: herbívoros, filtradores, carnívoros y herbívoros -filtradores. Se obtuvo un total de 14 581 individuos (6 397.945 g representado por 68 especies correspondientes a las clases Gastropoda (39, Bivalvia (23 y Polyplacophora (6; contenidas en nueve órdenes y 31 familias. Los herbívoros fueron el grupo dominante (49%, seguido por filtradores (37%, carnívoros (13 % y herbívoros-filtradores (1%. Las especies herbívoras y herbívoras-filtradoras dominaron en el área protegida, mientras que en el área expuesta, fueron las carnívoras y filtradoras. Las especies constantes en las seis localidades durante el período de estudio fueron Planaxis nucleus, Mitrella ocellata, M. nycteis, Littorina interrupta, Tegula fasciata, Acmaea leucopleura, Ostrea equestris y Chiton squamosus. La distribución de los moluscos y los diferentes grupos tróficos, pueden estar controlados por adaptaciones morfológicas, así como el nivel de exposición al oleaje y composición del sustrato.Mollusc community structure and trophic relations in the rochy littoral zone in Sucre State

Ação da inoculação de hemolinfa no mecanismo de defesa de Biomphalaria tenagophila (Orbigny, 1835

Directory of Open Access Journals (Sweden)

Reis Soely Maria Pissini Machado

1995-01-01

Full Text Available Estudou-se a resistência à infecção pelo S. mansoni em moluscos B. tenagophila inoculados com vários tipos de hemolinfa provenientes de moluscos infectados por S. mansoni da linhagem SJ ou por outros trematódeos avaliando-se, nestas circunstâncias, o comportamento dos amebócitos. Concluiu-se que dois tipos de mecanismos teriam agido provocando resistência à infecção pelo S. mansoni: celular e humoral. A reação do tipo celular ocorreu quando os moluscos eram inoculados com hemolinfa de moluscos infectados por S. mansoni B. tenagophila inoculadas com hemolinfa de moluscos infectados por furcocercárias longifurcadas sem ocelos, apresentaram elevada resistência à infecção posterior por S.mansoni.

Ação da inoculação de hemolinfa no mecanismo de defesa de Biomphalaria tenagophila (Orbigny, 1835

Directory of Open Access Journals (Sweden)

Soely Maria Pissini Machado Reis

1995-08-01

Full Text Available Estudou-se a resistência à infecção pelo S. mansoni em moluscos B. tenagophila inoculados com vários tipos de hemolinfa provenientes de moluscos infectados por S. mansoni da linhagem SJ ou por outros trematódeos avaliando-se, nestas circunstâncias, o comportamento dos amebócitos. Concluiu-se que dois tipos de mecanismos teriam agido provocando resistência à infecção pelo S. mansoni: celular e humoral. A reação do tipo celular ocorreu quando os moluscos eram inoculados com hemolinfa de moluscos infectados por S. mansoni B. tenagophila inoculadas com hemolinfa de moluscos infectados por furcocercárias longifurcadas sem ocelos, apresentaram elevada resistência à infecção posterior por S.mansoni.

Moluscos Poliplacóforos del litoral atlántico del sur de la Península Ibérica

Directory of Open Access Journals (Sweden)

Carmona Zalvide, M. P.

2000-12-01

Full Text Available In this paper, an updated check-list of the polyplacophoran species from Sagres (Portugal to Strait of Gibraltar is present. Twenty taxa are recorded in this area: Lepidopleurus cajetanus, Leptochiton cancellatus, Leptochiton algesirensis, Leptochiton scabridus, Callochiton septemvalvis, Callochiton euplaeae, Lepidochitona cinerea, Lepidochitona corrugata, Lepidochitona canariensis, Lepidochitona monterosatoi, Lepidochitona kaasi, Lepidochitona severianoi, Chaetopleura angulata, Ischnochiton rissoi, Chiton olivaceus, Chiton corallinus, Chiton phaesolinus, Acanthochitona fascicularis and Acanthochitona crinita. From these species, Lepidochitona canariensis, L simrothi, Callochiton septemvalvis and Lepidochitona monterosatoi amplify their geographical distribution to Southern Atlantic coast of southern Iberian Peninsula.

Se aporta el catálogo de los Moluscos Poliplacóforos de las costas atlánticas del sur de la Península Ibérica, desde Sagres (Portugal hasta Gibraltar. Se cita un total de 20 taxones (Lepidopleurus cajetanus, Leptochiton cancellatus, Leptochiton algesirensis, Leptochiton scabridus, Callochiton septemvalvis, Callochiton euplaeae, Lepidochitona cinerea, Lepidochitona corrugata, Lepidochitona canariensis, Lepidochitona monterosatoi, Lepidochitona kaasi, Lepidochitona severianoi, Chaetopleura angulata, Ischnochiton rissoi, Chiton olivaceus, Chiton corallinus, Chiton phaesolinus, Acanthochitona fascicularis y Acanthochitona crinita todos ellos pertenecientes al dominio litoral. La captura de Lepidochitona canariensis y L. simrothi en aguas atlánticas ibéricas constituye la primera cita para el suratlántico ibérico. A su vez se amplía la distribución a esta zona de Callochiton septemvalvis y de Lepidochitona monterosatoi.

RENDIMENTO DE CARCAÇA E COMPOSIÇÃO CENTESIMAL DO MÚSCULO DOS MOLUSCOS ESCARGOT (Achatina fulica E ARUÁ (Pomacea lineata

Directory of Open Access Journals (Sweden)

S. H. R. BARBOZA

2008-09-01

Full Text Available

O presente trabalho teve como objetivo avaliar a composição corporal (rendimento de carcaça e a composição centesimal do músculo dos moluscos escargot e aruá. As avaliações foram realizadas comparando-se 6 grupos de animais de pesos e idades diferentes (3 de escargot e 3 de aruá com um grupo controle (escargot, animais estes com 4 meses de idade e peso entre 20 e 25g (considerados pela Escargoteria animais padrão de abate. De interesse industrial, o rendimento em carne observado no lote de escargot de peso inferior (14,08 a 19,98g ao lote controle, mostra que podemos aproveitá-los para a comercialização, pois podem ser abatidos antes dos 4 meses de idade, pelo menor custo de produção. Já os lotes de aruá (espécie selvagem apresentaram discrepâncias quando comparado ao lote controle o que sugerem estudos zootécnicos para melhorar o rendimento em carne. Na composição centesimal da carne 02 lotes de escargot (1 e 2 e 02 lotes de aruá (4 e 5 são estatisticamente igual ao lote controle indicando o potencial nutricional da espécie aruá.

Emerging Vector-Borne Diseases - Incidence through Vectors.

Science.gov (United States)

Savić, Sara; Vidić, Branka; Grgić, Zivoslav; Potkonjak, Aleksandar; Spasojevic, Ljubica

2014-01-01

Vector-borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowadays, in intercontinental countries, there is a struggle with emerging diseases, which have found their way to appear through vectors. Vector-borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens, and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector-borne infectious diseases and disease outbreaks. It could affect the range and population of pathogens, host and vectors, transmission season, etc. Reliable surveillance for diseases that are most likely to emerge is required. Canine vector-borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, ehrlichiosis, and leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fundamental role at primarily prevention and then treatment of vector-borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases. During a 4-year period, from 2009 to 2013, a total number of 551 dog samples were analyzed for vector-borne diseases (borreliosis, babesiosis, ehrlichiosis, anaplasmosis, dirofilariosis, and leishmaniasis) in routine laboratory work. The analysis was done by serological tests - ELISA for borreliosis, dirofilariosis, and leishmaniasis, modified Knott test for dirofilariosis, and blood smear for babesiosis, ehrlichiosis, and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on average more then half of the samples

Vector analysis

CERN Document Server

Newell, Homer E

2006-01-01

When employed with skill and understanding, vector analysis can be a practical and powerful tool. This text develops the algebra and calculus of vectors in a manner useful to physicists and engineers. Numerous exercises (with answers) not only provide practice in manipulation but also help establish students' physical and geometric intuition in regard to vectors and vector concepts.Part I, the basic portion of the text, consists of a thorough treatment of vector algebra and the vector calculus. Part II presents the illustrative matter, demonstrating applications to kinematics, mechanics, and e

Vector-Tensor and Vector-Vector Decay Amplitude Analysis of B0→φK*0

International Nuclear Information System (INIS)

Aubert, B.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Ofte, I.; Stugu, B.; Abrams, G. S.

2007-01-01

We perform an amplitude analysis of the decays B 0 →φK 2 * (1430) 0 , φK * (892) 0 , and φ(Kπ) S-wave 0 with a sample of about 384x10 6 BB pairs recorded with the BABAR detector. The fractions of longitudinal polarization f L of the vector-tensor and vector-vector decay modes are measured to be 0.853 -0.069 +0.061 ±0.036 and 0.506±0.040±0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP violation

About vectors

CERN Document Server

Hoffmann, Banesh

1975-01-01

From his unusual beginning in ""Defining a vector"" to his final comments on ""What then is a vector?"" author Banesh Hoffmann has written a book that is provocative and unconventional. In his emphasis on the unresolved issue of defining a vector, Hoffmann mixes pure and applied mathematics without using calculus. The result is a treatment that can serve as a supplement and corrective to textbooks, as well as collateral reading in all courses that deal with vectors. Major topics include vectors and the parallelogram law; algebraic notation and basic ideas; vector algebra; scalars and scalar p

Vectors

DEFF Research Database (Denmark)

Boeriis, Morten; van Leeuwen, Theo

2017-01-01

should be taken into account in discussing ‘reactions’, which Kress and van Leeuwen link only to eyeline vectors. Finally, the question can be raised as to whether actions are always realized by vectors. Drawing on a re-reading of Rudolf Arnheim’s account of vectors, these issues are outlined......This article revisits the concept of vectors, which, in Kress and van Leeuwen’s Reading Images (2006), plays a crucial role in distinguishing between ‘narrative’, action-oriented processes and ‘conceptual’, state-oriented processes. The use of this concept in image analysis has usually focused...

Vector regression introduced

Directory of Open Access Journals (Sweden)

Mok Tik

2014-06-01

Full Text Available This study formulates regression of vector data that will enable statistical analysis of various geodetic phenomena such as, polar motion, ocean currents, typhoon/hurricane tracking, crustal deformations, and precursory earthquake signals. The observed vector variable of an event (dependent vector variable is expressed as a function of a number of hypothesized phenomena realized also as vector variables (independent vector variables and/or scalar variables that are likely to impact the dependent vector variable. The proposed representation has the unique property of solving the coefficients of independent vector variables (explanatory variables also as vectors, hence it supersedes multivariate multiple regression models, in which the unknown coefficients are scalar quantities. For the solution, complex numbers are used to rep- resent vector information, and the method of least squares is deployed to estimate the vector model parameters after transforming the complex vector regression model into a real vector regression model through isomorphism. Various operational statistics for testing the predictive significance of the estimated vector parameter coefficients are also derived. A simple numerical example demonstrates the use of the proposed vector regression analysis in modeling typhoon paths.

Kochen-Specker vectors

International Nuclear Information System (INIS)

Pavicic, Mladen; Merlet, Jean-Pierre; McKay, Brendan; Megill, Norman D

2005-01-01

We give a constructive and exhaustive definition of Kochen-Specker (KS) vectors in a Hilbert space of any dimension as well as of all the remaining vectors of the space. KS vectors are elements of any set of orthonormal states, i.e., vectors in an n-dimensional Hilbert space, H n , n≥3, to which it is impossible to assign 1s and 0s in such a way that no two mutually orthogonal vectors from the set are both assigned 1 and that not all mutually orthogonal vectors are assigned 0. Our constructive definition of such KS vectors is based on algorithms that generate MMP diagrams corresponding to blocks of orthogonal vectors in R n , on algorithms that single out those diagrams on which algebraic (0)-(1) states cannot be defined, and on algorithms that solve nonlinear equations describing the orthogonalities of the vectors by means of statistically polynomially complex interval analysis and self-teaching programs. The algorithms are limited neither by the number of dimensions nor by the number of vectors. To demonstrate the power of the algorithms, all four-dimensional KS vector systems containing up to 24 vectors were generated and described, all three-dimensional vector systems containing up to 30 vectors were scanned, and several general properties of KS vectors were found

Elementary vectors

CERN Document Server

Wolstenholme, E Œ

1978-01-01

Elementary Vectors, Third Edition serves as an introductory course in vector analysis and is intended to present the theoretical and application aspects of vectors. The book covers topics that rigorously explain and provide definitions, principles, equations, and methods in vector analysis. Applications of vector methods to simple kinematical and dynamical problems; central forces and orbits; and solutions to geometrical problems are discussed as well. This edition of the text also provides an appendix, intended for students, which the author hopes to bridge the gap between theory and appl

Genetic manipulation of endosymbionts to control vector and vector borne diseases

Directory of Open Access Journals (Sweden)

Jay Prakash Gupta

Full Text Available Vector borne diseases (VBD are on the rise because of failure of the existing methods of control of vector and vector borne diseases and the climate change. A steep rise of VBDs are due to several factors like selection of insecticide resistant vector population, drug resistant parasite population and lack of effective vaccines against the VBDs. Environmental pollution, public health hazard and insecticide resistant vector population indicate that the insecticides are no longer a sustainable control method of vector and vector-borne diseases. Amongst the various alternative control strategies, symbiont based approach utilizing endosymbionts of arthropod vectors could be explored to control the vector and vector borne diseases. The endosymbiont population of arthropod vectors could be exploited in different ways viz., as a chemotherapeutic target, vaccine target for the control of vectors. Expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting arthropods may serve as a powerful approach to control certain arthropod-borne diseases. Genetic transformation of symbiotic bacteria of the arthropod vector to alter the vector’s ability to transmit pathogen is an alternative means of blocking the transmission of VBDs. In Indian scenario, where dengue, chikungunya, malaria and filariosis are prevalent, paratransgenic based approach can be used effectively. [Vet World 2012; 5(9.000: 571-576

Emerging vector borne diseases – incidence through vectors

Directory of Open Access Journals (Sweden)

Sara eSavic

2014-12-01

Full Text Available Vector borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowdays, in intercontinetal countries, there is a struggle with emerging diseases which have found their way to appear through vectors. Vector borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector borne infectious diseases and disease outbreaks. It could affect the range and popultion of pathogens, host and vectors, transmission season, etc. Reliable surveilance for diseases that are most likely to emerge is required. Canine vector borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, erlichiosis, leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fudamental role at primeraly prevention and then treatment of vector borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases.During a four year period, from 2009-2013, a total number of 551 dog samples were analysed for vector borne diseases (borreliosis, babesiosis, erlichiosis, anaplasmosis, dirofilariosis and leishmaniasis in routine laboratory work. The analysis were done by serological tests – ELISA for borreliosis, dirofilariosis and leishmaniasis, modified Knott test for dirofilariosis and blood smear for babesiosis, erlichiosis and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on avarege more then half of the samples

Vector-vector production in photon-photon interactions

International Nuclear Information System (INIS)

Ronan, M.T.

1988-01-01

Measurements of exclusive untagged /rho/ 0 /rho/ 0 , /rho//phi/, K/sup *//bar K//sup */, and /rho/ω production and tagged /rho/ 0 /rho/ 0 production in photon-photon interactions by the TPC/Two-Gamma experiment are reviewed. Comparisons to the results of other experiments and to models of vector-vector production are made. Fits to the data following a four quark model prescription for vector meson pair production are also presented. 10 refs., 9 figs

Rare Hadronic B Decays to Vector, Axial-Vector and Tensors

International Nuclear Information System (INIS)

Gao, Y.Y.

2011-01-01

The authors review BABAR measurements of several rare B decays, including vector-axial-vector decays B ± → φK 1 ± (1270), B ± → φ K 1 ± (1400) and B ± → b 1 # -+ρ# ± , vector-vector decays B ± → φK* ± (1410), B 0 → K* 0 (bar K)* 0 , B 0 → K*0K*0 and B 0 → K*+K*-, vector-tensor decays B ± → φK* 2 (1430) ± and φK 2 (1770)/ ± (1820), and vector-scalar decays B ± → φK* 0 (1430) ± . Understanding the observed polarization pattern requires amplitude contributions from an uncertain source.

Ocorrência de Achatina fulica no Vale do Paraíba, Estado do Rio de Janeiro, Brasil

Directory of Open Access Journals (Sweden)

Maurício Carvalho de Vasconcellos

2001-12-01

Full Text Available Registrou-se no município de Resende, Estado do Rio de Janeiro, Brasil, a primeira ocorrência do molusco Achatina fulica hospedeiro intermediário de Angiostrongylus cantonensis, causador da angiostrongilíase meningoencefálica. Em cinco bairros visitados, foram encontrados moluscos vivendo livremente, e nenhum dos animais coletados apresentava a forma larvar do parasito. A presença de A. fulica pode estar relacionada à comercialização desse molusco como alimento, e representa possibilidade de instalação dessa zoonose na região.

Ocorrência de Achatina fulica no Vale do Paraíba, Estado do Rio de Janeiro, Brasil

Directory of Open Access Journals (Sweden)

Vasconcellos Maurício Carvalho de

2001-01-01

Full Text Available Registrou-se no município de Resende, Estado do Rio de Janeiro, Brasil, a primeira ocorrência do molusco Achatina fulica hospedeiro intermediário de Angiostrongylus cantonensis, causador da angiostrongilíase meningoencefálica. Em cinco bairros visitados, foram encontrados moluscos vivendo livremente, e nenhum dos animais coletados apresentava a forma larvar do parasito. A presença de A. fulica pode estar relacionada à comercialização desse molusco como alimento, e representa possibilidade de instalação dessa zoonose na região.

Conhecimento tradicional das marisqueiras de Barra Grande, área de proteção ambiental do delta do Rio Parnaíba, Piauí, Brasil

OpenAIRE

Freitas, Simone Tupinambá; Pamplin, Paulo Augusto Zaitune; Legat, Jefferson; Fogaça, Fabíola Helena dos Santos; Barros, Roseli Farias Melo de

2012-01-01

Na comunidade de Barra Grande localizada no litoral do Piauí, as mulheres dos pescadores, conhecidas localmente como marisqueiras, extraem do manguezal vários tipos de moluscos para comercialização e em maior escala para a subsistência. Dados sobre a atividade de mariscagem, conceitos de conservação e aspectos socioeconômicos do contexto em que ocorre a atividade de cata dos moluscos, foram revelados após a aplicação de protocolos estruturados e semiestruturados. O molusco bivalve Anomalocard...

Vector analysis

CERN Document Server

Brand, Louis

2006-01-01

The use of vectors not only simplifies treatments of differential geometry, mechanics, hydrodynamics, and electrodynamics, but also makes mathematical and physical concepts more tangible and easy to grasp. This text for undergraduates was designed as a short introductory course to give students the tools of vector algebra and calculus, as well as a brief glimpse into these subjects' manifold applications. The applications are developed to the extent that the uses of the potential function, both scalar and vector, are fully illustrated. Moreover, the basic postulates of vector analysis are brou

Vectors and Rotations in 3-Dimensions: Vector Algebra for the C++ Programmer

Science.gov (United States)

2016-12-01

release; distribution is unlimited. 1. Introduction This report describes 2 C++ classes: a Vector class for performing vector algebra in 3-dimensional...ARL-TR-7894•DEC 2016 US Army Research Laboratory Vectors and Rotations in 3-Dimensions:Vector Algebra for the C++ Programmer by Richard Saucier...Army Research Laboratory Vectors and Rotations in 3-Dimensions:Vector Algebra for the C++ Programmer by Richard Saucier Survivability/Lethality

Measurement of Charmless B to Vector-Vector decays at BaBar

International Nuclear Information System (INIS)

Olaiya, Emmanuel

2011-01-01

The authors present results of B → vector-vector (VV) and B → vector-axial vector (VA) decays B 0 → φX(X = φ,ρ + or ρ 0 ), B + → φK (*)+ , B 0 → K*K*, B 0 → ρ + b 1 - and B + → K* 0 α 1 + . The largest dataset used for these results is based on 465 x 10 6 Υ(4S) → B(bar B) decays, collected with the BABAR detector at the PEP-II B meson factory located at the Stanford Linear Accelerator Center (SLAC). Using larger datasets, the BABAR experiment has provided more precise B → VV measurements, further supporting the smaller than expected longitudinal polarization fraction of B → φK*. Additional B meson to vector-vector and vector-axial vector decays have also been studied with a view to shedding light on the polarization anomaly. Taking into account the available errors, we find no disagreement between theory and experiment for these additional decays.

REVISIÓN DE LOS BIOCOREMAS MARINOS GLOBALES DEL JURÁSICO SEGÚN LA DISTRIBUCIÓN DE LOS MOLUSCOS BIVALVOS

Directory of Open Access Journals (Sweden)

Damborenea, Susana E.

2017-11-01

Full Text Available Numerosos trabajos regionales o locales han propuesto el reconocimiento de unidades biogeográficas de distintos rangos (biocoremas basadas sobre la distribución de los moluscos bivalvos para el Jurásico, pero no existía una síntesis a nivel mundial. Este trabajo es una revisión de las más significativas de esas propuestas, en un intento de lograr una síntesis de los patrones biogeográficos globales desde el Jurásico Temprano al Tardío, mientras se producían cambios sustanciales en la paleogeografía de la Tierra y los patrones de circulación oceánica como resultado de la disgregación de Pangea. Se hace también un breve análisis de la evolución en el tiempo y el espacio de cada una de las principales unidades reconocidas y de sus relaciones. Estos biocoremas pueden agruparse en tres unidades de primer orden que han tenido continuidad en el tiempo: Boreal, Tethys y Austral. Las unidades revisadas aquí han sido reconocidas y caracterizadas de forma muy heterogénea por los distintos autores, pero los criterios básicos más utilizados incluyen desde el grado de endemismo y la diversidad relativa, hasta las afinidades paleobiogeográficas de los taxones a nivel genérico. Los patrones de distribución de los bivalvos jurásicos no solamente son claves para entender cuestiones puramente biogeográficas, sino que han sido utilizados como argumento y evidencia en discusiones de índole paleogeográfica (como el establecimiento de corredores oceánicos, o patrones de circulación marina superficial, e incluso son pruebas de peso para la discusión de tópicos paleotectónicos, como la localización de terrenos desplazados y la deriva continental.

Vectorization of KENO IV code and an estimate of vector-parallel processing

International Nuclear Information System (INIS)

Asai, Kiyoshi; Higuchi, Kenji; Katakura, Jun-ichi; Kurita, Yutaka.

1986-10-01

The multi-group criticality safety code KENO IV has been vectorized and tested on FACOM VP-100 vector processor. At first the vectorized KENO IV on a scalar processor became slower than the original one by a factor of 1.4 because of the overhead introduced by the vectorization. Making modifications of algorithms and techniques for vectorization, the vectorized version has become faster than the original one by a factor of 1.4 and 3.0 on the vector processor for sample problems of complex and simple geometries, respectively. For further speedup of the code, some improvements on compiler and hardware, especially on addition of Monte Carlo pipelines to the vector processor, are discussed. Finally a pipelined parallel processor system is proposed and its performance is estimated. (author)

Suscetibilidade de biomphalaria glabrata, B. straminea e B. tenagophila a diferentes cepas de schistosoma mansoni

Directory of Open Access Journals (Sweden)

Luiz Candido de Souza Dias

1987-08-01

Full Text Available Em condições experimentais foi estudada a suscetibilidade de Biomphalaria glabrata, B. straminea e B. tenagophila a quatro linhagens humanas (MAP, PTH, UPH, e OuH e duas de roedores silvestres (PTR e VPR do Schistosoma mansoni. Grupos de 50 moluscos foram expostos individualmente a 10 miracídios e observados durante 70 dias. Avaliou-se a suscetibilidade dos moluscos ao parasito por meio da % de animais com esporocistos, % de moluscos que eliminavam cercárias e mortalidade conjunta dos animais expostos e infectados. Exemplares de B. glabrata mineira infectaram-se com cepa simpátrica (MAP e com 5 alopátricas do Estado de São Paulo (PTH, VPH, OuH, PTR e VPR. B. glabrata paulista mostrou altas taxas de infecção com as cepas MAP, VPR e OuH do trematódeo. Quatro % dos exemplares B. straminea de São Paulo eliminavam cercárias de cepas simpátricas; com cepa mineira apenas 4% apresentaram esporocistos na vigência de 20 miracídios por molusco; as menores taxas de mortalidade foram registradas com essa espécie de molusco, não sendo maior do que 20%. B. tenagophila paulista foi suscetível apenas às linhagens simpáticas sendo 6% a maior taxa de moluscos que eliminaram cercárias. Os resultados indicam que os movimentos populacionais humanos dentro do território paulista e para fora dele são importantes na disseminação da esquistossomose mansônica.

Versatile generation of optical vector fields and vector beams using a non-interferometric approach.

Science.gov (United States)

Tripathi, Santosh; Toussaint, Kimani C

2012-05-07

We present a versatile, non-interferometric method for generating vector fields and vector beams which can produce all the states of polarization represented on a higher-order Poincaré sphere. The versatility and non-interferometric nature of this method is expected to enable exploration of various exotic properties of vector fields and vector beams. To illustrate this, we study the propagation properties of some vector fields and find that, in general, propagation alters both their intensity and polarization distribution, and more interestingly, converts some vector fields into vector beams. In the article, we also suggest a modified Jones vector formalism to represent vector fields and vector beams.

Vectorized Monte Carlo

International Nuclear Information System (INIS)

Brown, F.B.

1981-01-01

Examination of the global algorithms and local kernels of conventional general-purpose Monte Carlo codes shows that multigroup Monte Carlo methods have sufficient structure to permit efficient vectorization. A structured multigroup Monte Carlo algorithm for vector computers is developed in which many particle events are treated at once on a cell-by-cell basis. Vectorization of kernels for tracking and variance reduction is described, and a new method for discrete sampling is developed to facilitate the vectorization of collision analysis. To demonstrate the potential of the new method, a vectorized Monte Carlo code for multigroup radiation transport analysis was developed. This code incorporates many features of conventional general-purpose production codes, including general geometry, splitting and Russian roulette, survival biasing, variance estimation via batching, a number of cutoffs, and generalized tallies of collision, tracklength, and surface crossing estimators with response functions. Predictions of vectorized performance characteristics for the CYBER-205 were made using emulated coding and a dynamic model of vector instruction timing. Computation rates were examined for a variety of test problems to determine sensitivities to batch size and vector lengths. Significant speedups are predicted for even a few hundred particles per batch, and asymptotic speedups by about 40 over equivalent Amdahl 470V/8 scalar codes arepredicted for a few thousand particles per batch. The principal conclusion is that vectorization of a general-purpose multigroup Monte Carlo code is well worth the significant effort required for stylized coding and major algorithmic changes

Vector Network Coding

OpenAIRE

Ebrahimi, Javad; Fragouli, Christina

2010-01-01

We develop new algebraic algorithms for scalar and vector network coding. In vector network coding, the source multicasts information by transmitting vectors of length L, while intermediate nodes process and combine their incoming packets by multiplying them with L X L coding matrices that play a similar role as coding coefficients in scalar coding. Our algorithms for scalar network jointly optimize the employed field size while selecting the coding coefficients. Similarly, for vector co...

Vector independent transmission of the vector-borne bluetongue virus.

Science.gov (United States)

van der Sluijs, Mirjam Tineke Willemijn; de Smit, Abraham J; Moormann, Rob J M

2016-01-01

Bluetongue is an economically important disease of ruminants. The causative agent, Bluetongue virus (BTV), is mainly transmitted by insect vectors. This review focuses on vector-free BTV transmission, and its epizootic and economic consequences. Vector-free transmission can either be vertical, from dam to fetus, or horizontal via direct contract. For several BTV-serotypes, vertical (transplacental) transmission has been described, resulting in severe congenital malformations. Transplacental transmission had been mainly associated with live vaccine strains. Yet, the European BTV-8 strain demonstrated a high incidence of transplacental transmission in natural circumstances. The relevance of transplacental transmission for the epizootiology is considered limited, especially in enzootic areas. However, transplacental transmission can have a substantial economic impact due to the loss of progeny. Inactivated vaccines have demonstrated to prevent transplacental transmission. Vector-free horizontal transmission has also been demonstrated. Since direct horizontal transmission requires close contact of animals, it is considered only relevant for within-farm spreading of BTV. The genetic determinants which enable vector-free transmission are present in virus strains circulating in the field. More research into the genetic changes which enable vector-free transmission is essential to better evaluate the risks associated with outbreaks of new BTV serotypes and to design more appropriate control measures.

VectorBase

Data.gov (United States)

U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

Custodial vector model

DEFF Research Database (Denmark)

Becciolini, Diego; Franzosi, Diogo Buarque; Foadi, Roshan

2015-01-01

We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a $SU(2)_L\\times SU(2)_R$ spectral global symmetry. This symmetry partially protects the electroweak S-parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum...

Experimental demonstration of vector E x vector B plasma divertor

International Nuclear Information System (INIS)

Strait, E.J.; Kerst, D.W.; Sprott, J.C.

1977-01-01

The vector E x vector B drift due to an applied radial electric field in a tokamak with poloidal divertor can speed the flow of plasma out of the scrape-off region, and provide a means of externally controlling the flow rate and thus the width of the density fall-off. An experiment in the Wisconsin levitated toroidal octupole, using vector E x vector B drifts alone, demonstrates divertor-like behavior, including 70% reduction of plasma density near the wall and 40% reduction of plasma flux to the wall, with no adverse effects on confinement of the main plasma

Rotations with Rodrigues' vector

International Nuclear Information System (INIS)

Pina, E

2011-01-01

The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears to be a fundamental matrix that is used to express the components of the angular velocity, the rotation matrix and the angular momentum vector. The Hamiltonian formalism of rotational dynamics in terms of this vector uses the same matrix. The quantization of the rotational dynamics is performed with simple rules if one uses Rodrigues' vector and similar formal expressions for the quantum operators that mimic the Hamiltonian classical dynamics.

Violation of vector dominance in the vector manifestation

International Nuclear Information System (INIS)

Sasaki, Chihiro

2003-01-01

The vector manifestation (VM) is a new pattern for realizing the chiral symmetry in QCD. In the VM, the massless vector meson becomes the chiral partner of pion at the critical point, in contrast with the restoration based on the linear sigma model. Including the intrinsic temperature dependences of the parameters of the hidden local symmetry (HLS) Lagrangian determined from the underlying QCD through the Wilsonian matching together with the hadronic thermal corrections, we present a new prediction of the VM on the direct photon-π-π coupling which measures the validity of the vector dominance (VD) of the electromagnetic form factor of the pion. We find that the VD is largely violated at the critical temperature, which indicates that the assumption of the VD made in several analysis on the dilepton spectra in hot matter may need to be weakened for consistently including the effect of the dropping mass of the vector meson. (author)

Diversidad y abundancia de moluscos de la epifauna en la comunidad sublitoral de Punta Patilla,Venezuela

Directory of Open Access Journals (Sweden)

Antulio Prieto A

2005-06-01

Full Text Available Se estudió la diversidad de una comunidad malacológica sublitoral en Punta Patilla, Estado Sucre, Venezuela, desde septiembre 1990 hasta septiembre 1991. Se identificaron 25 especies, 14 bivalvos y 11 gasterópodos. Los parámetros de diversidad total en número de la comunidad fueron H´=3.41 bits/ind., J´=0.74 y 1-D =0.85. Las máximas diversidades mensuales se observaron en marzo 1991 (3.12 bits/ind., junio 1991 (2.88 bits/ind y septiembre 1991 (2.95 bits/ind. y la mínima ocurrió en agosto 1991 (1.20 bits/ind.. Los datos del número de individuos conforman una línea recta ajustada por la serie logarítmica con un índice alfa =4.56 y alfa =3.11 para los de biomasa. Las especies más abundantes fueron Chione cancellata, Antigona listeri, Chione granulata y Arca zebra entre los bivalvos, y Chicoreus brevifrons, Turritella variegata y Phyllonotus pomum entre los gasterópodos, estos presentaron las máximas biomasas individuales. La biomasa total promedio de la comunidad (56.80 g/m² es baja cuando se compara con otros reportes de áreas tropicales. Los moluscos habitaron fondos de grava y arenofangoso cubiertos por praderas de Thalasia testudinumDiversity and abundance of mollusks in the sublittoral epifaunal community of Punta Patilla, Venezuela. The diversity of a sublittoral epifaunal mollusk community of Punta Patilla, Sucre State, Venezuela, was studied from September 1990 to September 1991. We identified 25 species (14 bivalves and 11 gastropods of mollusks that inhabit gravel, soft sand and bottoms covered by Thalassia testudinum.Total diversity indices were H´= 3.42, J´= 0.74 and 1-D = 0.85. Monthly diversity reached its maximum in March 1991 (3.12 bits/ ind., June 1991 (2.88 bits/ind. and September 1991 (2.95 bits/ind.; minimum diversity was recorded in August 1991 (1.20 bits/ind..A log series model showed a diversity index alpha = 4.56 for species abundance data and alpha = 3.11 for biomass data. The more abundant species were

Measurement of K/sub NN/, K/sub LL/ in p vector d → n vector X and p vector 9Be → n vector X at 800 MeV

International Nuclear Information System (INIS)

Riley, P.J.; Hollas, C.L.; Newsom, C.R.

1980-01-01

The spin transfer parameters, K/sub NN/ and K/sub LL/, have been measured in p vector d → n vector X and p vector 9 Be → n vector X at 0 0 and 800 MeV. The rather large values of K/sub LL/ demonstrate that this transfer mechanism will provide a useful source of polarized neutrons at LAMPF energies

Raster images vectorization system

OpenAIRE

Genytė, Jurgita

2006-01-01

The problem of raster images vectorization was analyzed and researched in this work. Existing vectorization systems are quite expensive, the results are inaccurate, and the manual vectorization of a large number of drafts is impossible. That‘s why our goal was to design and develop a new raster images vectorization system using our suggested automatic vectorization algorithm and the way to record results in a new universal vectorial file format. The work consists of these main parts: analysis...

Vectorization of phase space Monte Carlo code in FACOM vector processor VP-200

International Nuclear Information System (INIS)

Miura, Kenichi

1986-01-01

This paper describes the vectorization techniques for Monte Carlo codes in Fujitsu's Vector Processor System. The phase space Monte Carlo code FOWL is selected as a benchmark, and scalar and vector performances are compared. The vectorized kernel Monte Carlo routine which contains heavily nested IF tests runs up to 7.9 times faster in vector mode than in scalar mode. The overall performance improvement of the vectorized FOWL code over the original scalar code reaches 3.3. The results of this study strongly indicate that supercomputer can be a powerful tool for Monte Carlo simulations in high energy physics. (Auth.)

Vector grammars and PN machines

Institute of Scientific and Technical Information of China (English)

蒋昌俊

1996-01-01

The concept of vector grammars under the string semantic is introduced.The dass of vector grammars is given,which is similar to the dass of Chomsky grammars.The regular vector grammar is divided further.The strong and weak relation between the vector grammar and scalar grammar is discussed,so the spectrum system graph of scalar and vector grammars is made.The equivalent relation between the regular vector grammar and Petri nets (also called PN machine) is pointed.The hybrid PN machine is introduced,and its language is proved equivalent to the language of the context-free vector grammar.So the perfect relation structure between vector grammars and PN machines is formed.

Vector velocimeter

DEFF Research Database (Denmark)

2012-01-01

The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...

Cloning vector

Science.gov (United States)

Guilfoyle, Richard A.; Smith, Lloyd M.

1994-01-01

A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site.

Cloning vector

Science.gov (United States)

Guilfoyle, R.A.; Smith, L.M.

1994-12-27

A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site. 2 figures.

Vector 33: A reduce program for vector algebra and calculus in orthogonal curvilinear coordinates

Science.gov (United States)

Harper, David

1989-06-01

This paper describes a package with enables REDUCE 3.3 to perform algebra and calculus operations upon vectors. Basic algebraic operations between vectors and between scalars and vectors are provided, including scalar (dot) product and vector (cross) product. The vector differential operators curl, divergence, gradient and Laplacian are also defined, and are valid in any orthogonal curvilinear coordinate system. The package is written in RLISP to allow algebra and calculus to be performed using notation identical to that for operations. Scalars and vectors can be mixed quite freely in the same expression. The package will be of interest to mathematicians, engineers and scientists who need to perform vector calculations in orthogonal curvilinear coordinates.

Probing deformed orbitals with vector A( vector e, e' N)B reactions

International Nuclear Information System (INIS)

Garrido, E.; Caballero, J.A.; Moya de Guerra, E.; Sarriguren, P.; Udias, J.M.

1995-01-01

We present results for response functions and asymmetries in the nuclear reactions 37 vector Ar( vector e, e' n) 36 Ar and 37 vector K( vector e,e' p) 36 Ar at quasifree kinematics. We compare PWIA results obtained using deformed HF wave functions with PWIA and DWIA results obtained assuming a spherical mean field. We show that the complex structure of the deformed orbitals can be probed by coincidence measurements with polarized beam and targets. ((orig.))

Multi-perspective views of students’ difficulties with one-dimensional vector and two-dimensional vector

Science.gov (United States)

Fauzi, Ahmad; Ratna Kawuri, Kunthi; Pratiwi, Retno

2017-01-01

Researchers of students’ conceptual change usually collects data from written tests and interviews. Moreover, reports of conceptual change often simply refer to changes in concepts, such as on a test, without any identification of the learning processes that have taken place. Research has shown that students have difficulties with vectors in university introductory physics courses and high school physics courses. In this study, we intended to explore students’ understanding of one-dimensional and two-dimensional vector in multi perspective views. In this research, we explore students’ understanding through test perspective and interviews perspective. Our research study adopted the mixed-methodology design. The participants of this research were sixty students of third semester of physics education department. The data of this research were collected by testand interviews. In this study, we divided the students’ understanding of one-dimensional vector and two-dimensional vector in two categories, namely vector skills of the addition of one-dimensionaland two-dimensional vector and the relation between vector skills and conceptual understanding. From the investigation, only 44% of students provided correct answer for vector skills of the addition of one-dimensional and two-dimensional vector and only 27% students provided correct answer for the relation between vector skills and conceptual understanding.

Custodial vector model

Science.gov (United States)

Becciolini, Diego; Franzosi, Diogo Buarque; Foadi, Roshan; Frandsen, Mads T.; Hapola, Tuomas; Sannino, Francesco

2015-07-01

We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a S U (2 )L×S U (2 )R spectral global symmetry. This symmetry partially protects the electroweak S parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum and interactions with the standard model fields lead to distinct signatures at the LHC in the diboson, dilepton, and associated Higgs channels.

Vector Differential Calculus

OpenAIRE

HITZER, Eckhard MS

2002-01-01

This paper treats the fundamentals of the vector differential calculus part of universal geometric calculus. Geometric calculus simplifies and unifies the structure and notation of mathematics for all of science and engineering, and for technological applications. In order to make the treatment self-contained, I first compile all important geometric algebra relationships,which are necesssary for vector differential calculus. Then differentiation by vectors is introduced and a host of major ve...

Vectorization, parallelization and porting of nuclear codes. Vectorization and parallelization. Progress report fiscal 1999

Energy Technology Data Exchange (ETDEWEB)

Adachi, Masaaki; Ogasawara, Shinobu; Kume, Etsuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ishizuki, Shigeru; Nemoto, Toshiyuki; Kawasaki, Nobuo; Kawai, Wataru [Fujitsu Ltd., Tokyo (Japan); Yatake, Yo-ichi [Hitachi Ltd., Tokyo (Japan)

2001-02-01

Several computer codes in the nuclear field have been vectorized, parallelized and trans-ported on the FUJITSU VPP500 system, the AP3000 system, the SX-4 system and the Paragon system at Center for Promotion of Computational Science and Engineering in Japan Atomic Energy Research Institute. We dealt with 18 codes in fiscal 1999. These results are reported in 3 parts, i.e., the vectorization and the parallelization part on vector processors, the parallelization part on scalar processors and the porting part. In this report, we describe the vectorization and parallelization on vector processors. In this vectorization and parallelization on vector processors part, the vectorization of Relativistic Molecular Orbital Calculation code RSCAT, a microscopic transport code for high energy nuclear collisions code JAM, three-dimensional non-steady thermal-fluid analysis code STREAM, Relativistic Density Functional Theory code RDFT and High Speed Three-Dimensional Nodal Diffusion code MOSRA-Light on the VPP500 system and the SX-4 system are described. (author)

Elliptic-symmetry vector optical fields.

Science.gov (United States)

Pan, Yue; Li, Yongnan; Li, Si-Min; Ren, Zhi-Cheng; Kong, Ling-Jun; Tu, Chenghou; Wang, Hui-Tian

2014-08-11

We present in principle and demonstrate experimentally a new kind of vector fields: elliptic-symmetry vector optical fields. This is a significant development in vector fields, as this breaks the cylindrical symmetry and enriches the family of vector fields. Due to the presence of an additional degrees of freedom, which is the interval between the foci in the elliptic coordinate system, the elliptic-symmetry vector fields are more flexible than the cylindrical vector fields for controlling the spatial structure of polarization and for engineering the focusing fields. The elliptic-symmetry vector fields can find many specific applications from optical trapping to optical machining and so on.

Chikungunya Virus–Vector Interactions

Directory of Open Access Journals (Sweden)

Lark L. Coffey

2014-11-01

Full Text Available Chikungunya virus (CHIKV is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed.

Extended vector-tensor theories

Energy Technology Data Exchange (ETDEWEB)

Kimura, Rampei; Naruko, Atsushi; Yoshida, Daisuke, E-mail: rampei@th.phys.titech.ac.jp, E-mail: naruko@th.phys.titech.ac.jp, E-mail: yoshida@th.phys.titech.ac.jp [Department of Physics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)

2017-01-01

Recently, several extensions of massive vector theory in curved space-time have been proposed in many literatures. In this paper, we consider the most general vector-tensor theories that contain up to two derivatives with respect to metric and vector field. By imposing a degeneracy condition of the Lagrangian in the context of ADM decomposition of space-time to eliminate an unwanted mode, we construct a new class of massive vector theories where five degrees of freedom can propagate, corresponding to three for massive vector modes and two for massless tensor modes. We find that the generalized Proca and the beyond generalized Proca theories up to the quartic Lagrangian, which should be included in this formulation, are degenerate theories even in curved space-time. Finally, introducing new metric and vector field transformations, we investigate the properties of thus obtained theories under such transformations.

Hyperbolic-symmetry vector fields.

Science.gov (United States)

Gao, Xu-Zhen; Pan, Yue; Cai, Meng-Qiang; Li, Yongnan; Tu, Chenghou; Wang, Hui-Tian

2015-12-14

We present and construct a new kind of orthogonal coordinate system, hyperbolic coordinate system. We present and design a new kind of local linearly polarized vector fields, which is defined as the hyperbolic-symmetry vector fields because the points with the same polarization form a series of hyperbolae. We experimentally demonstrate the generation of such a kind of hyperbolic-symmetry vector optical fields. In particular, we also study the modified hyperbolic-symmetry vector optical fields with the twofold and fourfold symmetric states of polarization when introducing the mirror symmetry. The tight focusing behaviors of these vector fields are also investigated. In addition, we also fabricate micro-structures on the K9 glass surfaces by several tightly focused (modified) hyperbolic-symmetry vector fields patterns, which demonstrate that the simulated tightly focused fields are in good agreement with the fabricated micro-structures.

Supergravity inspired vector curvaton

International Nuclear Information System (INIS)

Dimopoulos, Konstantinos

2007-01-01

It is investigated whether a massive Abelian vector field, whose gauge kinetic function is growing during inflation, can be responsible for the generation of the curvature perturbation in the Universe. Particle production is studied and it is shown that the vector field can obtain a scale-invariant superhorizon spectrum of perturbations with a reasonable choice of kinetic function. After inflation the vector field begins coherent oscillations, during which it corresponds to pressureless isotropic matter. When the vector field dominates the Universe, its perturbations give rise to the observed curvature perturbation following the curvaton scenario. It is found that this is possible if, after the end of inflation, the mass of the vector field increases at a phase transition at temperature of order 1 TeV or lower. Inhomogeneous reheating, whereby the vector field modulates the decay rate of the inflaton, is also studied

Constraining vectors and axial-vectors in walking technicolour by a holographic principle

DEFF Research Database (Denmark)

D. Dietrich, Dennis; Kouvaris, Christoforos

2008-01-01

We use a holographic principle to study the low-energy spectrum of walking technicolour models. In particular, we predict the masses of the axial vectors as well as the decay constants of vectors and axial vectors as functions of the mass of the techni-rho. Given that there are very few...

Ação da inoculação de hemolinfa no mecanismo de defesa de Biomphalaria tenagophila (Orbigny, 1835 The effect of hemolymph inoculation on the defense mechanism of Biomphalaria tenagophila (Orbigny, 1835

Directory of Open Access Journals (Sweden)

Soely Maria Pissini Machado Reis

1995-08-01

Full Text Available Estudou-se a resistência à infecção pelo S. mansoni em moluscos B. tenagophila inoculados com vários tipos de hemolinfa provenientes de moluscos infectados por S. mansoni da linhagem SJ ou por outros trematódeos avaliando-se, nestas circunstâncias, o comportamento dos amebócitos. Concluiu-se que dois tipos de mecanismos teriam agido provocando resistência à infecção pelo S. mansoni: celular e humoral. A reação do tipo celular ocorreu quando os moluscos eram inoculados com hemolinfa de moluscos infectados por S. mansoni B. tenagophila inoculadas com hemolinfa de moluscos infectados por furcocercárias longifurcadas sem ocelos, apresentaram elevada resistência à infecção posterior por S.mansoni.The resistance of B. tenagophila snails to infection by Schistosoma mansoni was studied. These snails had been previously inoculated with hemolymph talsen from other snails infected by S. mansoni of SJ strain or by other trematodes. The findings suggest that two types - cellular and humoral - are responsible for the resistance to infection by S. mansoni. The cellular response occurred when the snails were inoculated with hemolymph from snails infected by S. mansoni. B. tenagophila inoculate with hemolymph from snails infected by furcocercariae without eye-spot, also showed resistance to the infection by S. mansoni. In this latter case, the degenerated sporocysts were not enveloped by amebocitary reaction, leading to the conclusion that humoral factors could be involved.

Recommendation on vectors and vector-transmitted diseases

OpenAIRE

Netherlands Food and Consumer Product Safety Authority

2009-01-01

In view of their increasing risk of introduction and their possible implications in causing major disease outbreaks, vectors, as well as vector-transmitted diseases like dengue, West Nile disease, Lyme disease and bluetongue need to be recognised as a threat to public and animal health and to the economy, also in the Netherlands. There has been an increase in the incidence of these diseases in the past two to three decades. Climate changes and changes in the use of land, water managemen...

Gauge anomaly with vector and axial-vector fields in 6D curved space

Science.gov (United States)

Yajima, Satoshi; Eguchi, Kohei; Fukuda, Makoto; Oka, Tomonori

2018-03-01

Imposing the conservation equation of the vector current for a fermion of spin 1/2 at the quantum level, a gauge anomaly for the fermion coupling with non-Abelian vector and axial-vector fields in 6D curved space is expressed in tensorial form. The anomaly consists of terms that resemble the chiral U(1) anomaly and the commutator terms that disappear if the axial-vector field is Abelian.

Vector manifestation and violation of vector dominance in hot matter

International Nuclear Information System (INIS)

Harada, Masayasu; Sasaki, Chihiro

2004-01-01

We show the details of the calculation of the hadronic thermal corrections to the two-point functions in the effective field theory of QCD for pions and vector mesons based on the hidden local symmetry (HLS) in hot matter using the background field gauge. We study the temperature dependence of the pion velocity in the low-temperature region determined from the hadronic thermal corrections, and show that, due to the presence of the dynamical vector meson, the pion velocity is smaller than the speed of the light already at one-loop level, in contrast to the result obtained in the ordinary chiral perturbation theory including only the pion at one-loop. Including the intrinsic temperature dependences of the parameters of the HLS Lagrangian determined from the underlying QCD through the Wilsonian matching, we show how the vector manifestation (VM), in which the massless vector meson becomes the chiral partner of pion, is realized at the critical temperature. We present a new prediction of the VM on the direct photon-π-π coupling which measures the validity of the vector dominance (VD) of the electromagnetic form factor of the pion: we find that the VD is largely violated at the critical temperature, which indicates that the assumption of the VD made in several analyses on the dilepton spectra in hot matter may need to be weakened for consistently including the effect of the dropping mass of the vector meson

Heavy Scalar, Vector, and Axial-Vector Mesons in Hot and Dense Nuclear Medium

Directory of Open Access Journals (Sweden)

Arvind Kumar

2014-01-01

Full Text Available In this work we shall investigate the mass modifications of scalar mesons (D0; B0, vector mesons (D*; B*, and axial-vector mesons (D1; B1 at finite density and temperature of the nuclear medium. The above mesons are modified in the nuclear medium through the modification of quark and gluon condensates. We will find the medium modification of quark and gluon condensates within chiral SU(3 model through the medium modification of scalar-isoscalar fields σ and ζ at finite density and temperature. These medium modified quark and gluon condensates will further be used through QCD sum rules for the evaluation of in-medium properties of the above mentioned scalar, vector, and axial vector mesons. We will also discuss the effects of density and temperature of the nuclear medium on the scattering lengths of the above scalar, vector, and axial-vector mesons. The study of the medium modifications of the above mesons may be helpful for understanding their production rates in heavy-ion collision experiments. The results of present investigations of medium modifications of scalar, vector, and axial-vector mesons at finite density and temperature can be verified in the compressed baryonic matter (CBM experiment of FAIR facility at GSI, Germany.

Vector Fields on Product Manifolds

OpenAIRE

Kurz, Stefan

2011-01-01

This short report establishes some basic properties of smooth vector fields on product manifolds. The main results are: (i) On a product manifold there always exists a direct sum decomposition into horizontal and vertical vector fields. (ii) Horizontal and vertical vector fields are naturally isomorphic to smooth families of vector fields defined on the factors. Vector fields are regarded as derivations of the algebra of smooth functions.

Light scattering of rectangular slot antennas: parallel magnetic vector vs perpendicular electric vector

Science.gov (United States)

Lee, Dukhyung; Kim, Dai-Sik

2016-01-01

We study light scattering off rectangular slot nano antennas on a metal film varying incident polarization and incident angle, to examine which field vector of light is more important: electric vector perpendicular to, versus magnetic vector parallel to the long axis of the rectangle. While vector Babinet’s principle would prefer magnetic field along the long axis for optimizing slot antenna function, convention and intuition most often refer to the electric field perpendicular to it. Here, we demonstrate experimentally that in accordance with vector Babinet’s principle, the incident magnetic vector parallel to the long axis is the dominant component, with the perpendicular incident electric field making a small contribution of the factor of 1/|ε|, the reciprocal of the absolute value of the dielectric constant of the metal, owing to the non-perfectness of metals at optical frequencies.

Generalization of concurrence vectors

International Nuclear Information System (INIS)

Yu Changshui; Song Heshan

2004-01-01

In this Letter, based on the generalization of concurrence vectors for bipartite pure state with respect to employing tensor product of generators of the corresponding rotation groups, we generalize concurrence vectors to the case of mixed states; a new criterion of separability of multipartite pure states is given out, for which we define a concurrence vector; we generalize the vector to the case of multipartite mixed state and give out a good measure of free entanglement

Vector Network Coding Algorithms

OpenAIRE

Ebrahimi, Javad; Fragouli, Christina

2010-01-01

We develop new algebraic algorithms for scalar and vector network coding. In vector network coding, the source multicasts information by transmitting vectors of length L, while intermediate nodes process and combine their incoming packets by multiplying them with L x L coding matrices that play a similar role as coding c in scalar coding. Our algorithms for scalar network jointly optimize the employed field size while selecting the coding coefficients. Similarly, for vector coding, our algori...

Complex Polynomial Vector Fields

DEFF Research Database (Denmark)

Dias, Kealey

vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields.......The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...

Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields.

Science.gov (United States)

Henan Zhao; Bryant, Garnett W; Griffin, Wesley; Terrill, Judith E; Jian Chen

2017-06-01

We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks.

Vectorization, parallelization and porting of nuclear codes (vectorization and parallelization). Progress report fiscal 1998

International Nuclear Information System (INIS)

Ishizuki, Shigeru; Kawai, Wataru; Nemoto, Toshiyuki; Ogasawara, Shinobu; Kume, Etsuo; Adachi, Masaaki; Kawasaki, Nobuo; Yatake, Yo-ichi

2000-03-01

Several computer codes in the nuclear field have been vectorized, parallelized and transported on the FUJITSU VPP500 system, the AP3000 system and the Paragon system at Center for Promotion of Computational Science and Engineering in Japan Atomic Energy Research Institute. We dealt with 12 codes in fiscal 1998. These results are reported in 3 parts, i.e., the vectorization and parallelization on vector processors part, the parallelization on scalar processors part and the porting part. In this report, we describe the vectorization and parallelization on vector processors. In this vectorization and parallelization on vector processors part, the vectorization of General Tokamak Circuit Simulation Program code GTCSP, the vectorization and parallelization of Molecular Dynamics NTV (n-particle, Temperature and Velocity) Simulation code MSP2, Eddy Current Analysis code EDDYCAL, Thermal Analysis Code for Test of Passive Cooling System by HENDEL T2 code THANPACST2 and MHD Equilibrium code SELENEJ on the VPP500 are described. In the parallelization on scalar processors part, the parallelization of Monte Carlo N-Particle Transport code MCNP4B2, Plasma Hydrodynamics code using Cubic Interpolated Propagation Method PHCIP and Vectorized Monte Carlo code (continuous energy model / multi-group model) MVP/GMVP on the Paragon are described. In the porting part, the porting of Monte Carlo N-Particle Transport code MCNP4B2 and Reactor Safety Analysis code RELAP5 on the AP3000 are described. (author)

Equivalent Vectors

Science.gov (United States)

Levine, Robert

2004-01-01

The cross-product is a mathematical operation that is performed between two 3-dimensional vectors. The result is a vector that is orthogonal or perpendicular to both of them. Learning about this for the first time while taking Calculus-III, the class was taught that if AxB = AxC, it does not necessarily follow that B = C. This seemed baffling. The…

Speculative dynamic vectorization to assist static vectorization in a HW/SW co-designed environment

OpenAIRE

Kumar, R.; Martinez, A.; Gonzalez, A.

2013-01-01

Compiler based static vectorization is used widely to extract data level parallelism from computation intensive applications. Static vectorization is very effective in vectorizing traditional array based applications. However, compilers inability to reorder ambiguous memory references severely limits vectorization opportunities, especially in pointer rich applications. HW/SW co-designed processors provide an excellent opportunity to optimize the applications at runtime. The availability of dy...

Vectorization at the KENO-IV code

International Nuclear Information System (INIS)

Asai, K.; Higuchi, K.; Katakura, J.

1986-01-01

The multigroup criticality safety code KENO-IV has been vectorized and tested on the FACOM VP-100 vector processor. At first, the vectorized KENO-IV on a scalar processor was slower than the original one by a factor of 1.4 because of the overhead introduced by vectorization. Making modifications of algorithms and techniques for vectorization, the vectorized version has become faster than the original one by a factor of 1.4 on the vector processor. For further speedup of the code, some improvements on compiler and hardware, especially on addition of Monte Carlo pipelines to the vector processor, are discussed

Reciprocity relationships in vector acoustics and their application to vector field calculations.

Science.gov (United States)

Deal, Thomas J; Smith, Kevin B

2017-08-01

The reciprocity equation commonly stated in underwater acoustics relates pressure fields and monopole sources. It is often used to predict the pressure measured by a hydrophone for multiple source locations by placing a source at the hydrophone location and calculating the field everywhere for that source. A similar equation that governs the orthogonal components of the particle velocity field is needed to enable this computational method to be used for acoustic vector sensors. This paper derives a general reciprocity equation that accounts for both monopole and dipole sources. This vector-scalar reciprocity equation can be used to calculate individual components of the received vector field by altering the source type used in the propagation calculation. This enables a propagation model to calculate the received vector field components for an arbitrary number of source locations with a single model run for each vector field component instead of requiring one model run for each source location. Application of the vector-scalar reciprocity principle is demonstrated with analytic solutions for a range-independent environment and with numerical solutions for a range-dependent environment using a parabolic equation model.

Vectors and their applications

CERN Document Server

Pettofrezzo, Anthony J

2005-01-01

Geared toward undergraduate students, this text illustrates the use of vectors as a mathematical tool in plane synthetic geometry, plane and spherical trigonometry, and analytic geometry of two- and three-dimensional space. Its rigorous development includes a complete treatment of the algebra of vectors in the first two chapters.Among the text's outstanding features are numbered definitions and theorems in the development of vector algebra, which appear in italics for easy reference. Most of the theorems include proofs, and coordinate position vectors receive an in-depth treatment. Key concept

Convexity and Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2002-01-01

In this paper we construct sets of marginal vectors of a TU game with the property that if the marginal vectors from these sets are core elements, then the game is convex.This approach leads to new upperbounds on the number of marginal vectors needed to characterize convexity.An other result is that

Integrating Transgenic Vector Manipulation with Clinical Interventions to Manage Vector-Borne Diseases.

Directory of Open Access Journals (Sweden)

Kenichi W Okamoto

2016-03-01

Full Text Available Many vector-borne diseases lack effective vaccines and medications, and the limitations of traditional vector control have inspired novel approaches based on using genetic engineering to manipulate vector populations and thereby reduce transmission. Yet both the short- and long-term epidemiological effects of these transgenic strategies are highly uncertain. If neither vaccines, medications, nor transgenic strategies can by themselves suffice for managing vector-borne diseases, integrating these approaches becomes key. Here we develop a framework to evaluate how clinical interventions (i.e., vaccination and medication can be integrated with transgenic vector manipulation strategies to prevent disease invasion and reduce disease incidence. We show that the ability of clinical interventions to accelerate disease suppression can depend on the nature of the transgenic manipulation deployed (e.g., whether vector population reduction or replacement is attempted. We find that making a specific, individual strategy highly effective may not be necessary for attaining public-health objectives, provided suitable combinations can be adopted. However, we show how combining only partially effective antimicrobial drugs or vaccination with transgenic vector manipulations that merely temporarily lower vector competence can amplify disease resurgence following transient suppression. Thus, transgenic vector manipulation that cannot be sustained can have adverse consequences-consequences which ineffective clinical interventions can at best only mitigate, and at worst temporarily exacerbate. This result, which arises from differences between the time scale on which the interventions affect disease dynamics and the time scale of host population dynamics, highlights the importance of accounting for the potential delay in the effects of deploying public health strategies on long-term disease incidence. We find that for systems at the disease-endemic equilibrium, even

Complex Polynomial Vector Fields

DEFF Research Database (Denmark)

The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

Abundancia y riqueza de moluscos y crustáceos asociados a las raíces sumergidas del mangle rojo (Rhizophora mangle en la laguna de Bocaripo, Sucre, Venezuela

Directory of Open Access Journals (Sweden)

Jennellis Cedeño

2010-10-01

Full Text Available Las raíces de mangle son un importante hábitat para muchas especies. Se estudió la abundancia y riqueza de moluscos y crustáceos asociadas a las raíces sumergidas de Rhizophora mangle. Las muestras fueron recolectadas entre febrero 2005 y enero 2006, en la laguna de Bocaripo, costa norte del estado Sucre, Venezuela. Se establecieron cinco estaciones en la laguna; al azar en cada estación se escogieron dos raíces de mangle, fueron introducidas en bolsas plásticas; los organismos fueron obtenidos de la raíz raspando la superficie con un cuchillo, luego fueron separados y fijados en formalina al 10% para su posterior identificación. Se recolectaron 1 092 especimenes de moluscos, distribuidos en dos clases: Bivalvia y Gastropoda. La clase Bivalvia fue la más abundante con 943 individuos. La familia más representativa fue Mytilidae con 6 especies, siendo Musculus lateralis la especie dominante. Los crustáceos estuvieron representados por 372 organismos, pertenecientes a la clase Malacostraca, donde Panopeus herbstii (169 ind. fue la especie más abundante. Las familias Panopeidae, Porcellanidae y Majidae presentaron el mayor número de especies. La máxima abundancia se encontró en febrero (224 ind. con una riqueza de 25 especies y la mínima en noviembre (45 ind. con 12. Las estaciones 1 y 5 presentaron la mayor abundancia y riqueza de organismos, lo cual pudiera estar relacionado con condiciones ambientales favorables, como la mayor disponibilidad de microhábitats y oferta alimenticia; por el contrario la estación 4, presentó un ambiente más inhóspito, debido a los altos valores en la salinidad y temperatura, lo cual contribuye con la menor abundancia y riqueza de las especies presentes.Abundance and richness of mollusks and crustaceans associated to the submerged roots of red mangrove (Rhizophora mangle at Bocaripo Lagoon, Sucre, Venezuela. Mangrove roots are important habitats for many species. The abundance and richness of

Vector financial rogue waves

International Nuclear Information System (INIS)

Yan, Zhenya

2011-01-01

The coupled nonlinear volatility and option pricing model presented recently by Ivancevic is investigated, which generates a leverage effect, i.e., stock volatility is (negatively) correlated to stock returns, and can be regarded as a coupled nonlinear wave alternative of the Black–Scholes option pricing model. In this Letter, we analytically propose vector financial rogue waves of the coupled nonlinear volatility and option pricing model without an embedded w-learning. Moreover, we exhibit their dynamical behaviors for chosen different parameters. The vector financial rogue wave (rogon) solutions may be used to describe the possible physical mechanisms for the rogue wave phenomena and to further excite the possibility of relative researches and potential applications of vector rogue waves in the financial markets and other related fields. -- Highlights: ► We investigate the coupled nonlinear volatility and option pricing model. ► We analytically present vector financial rogue waves. ► The vector financial rogue waves may be used to describe the extreme events in financial markets. ► This results may excite the relative researches and potential applications of vector rogue waves.

Video Vectorization via Tetrahedral Remeshing.

Science.gov (United States)

Wang, Chuan; Zhu, Jie; Guo, Yanwen; Wang, Wenping

2017-02-09

We present a video vectorization method that generates a video in vector representation from an input video in raster representation. A vector-based video representation offers the benefits of vector graphics, such as compactness and scalability. The vector video we generate is represented by a simplified tetrahedral control mesh over the spatial-temporal video volume, with color attributes defined at the mesh vertices. We present novel techniques for simplification and subdivision of a tetrahedral mesh to achieve high simplification ratio while preserving features and ensuring color fidelity. From an input raster video, our method is capable of generating a compact video in vector representation that allows a faithful reconstruction with low reconstruction errors.

Selection vector filter framework

Science.gov (United States)

Lukac, Rastislav; Plataniotis, Konstantinos N.; Smolka, Bogdan; Venetsanopoulos, Anastasios N.

2003-10-01

We provide a unified framework of nonlinear vector techniques outputting the lowest ranked vector. The proposed framework constitutes a generalized filter class for multichannel signal processing. A new class of nonlinear selection filters are based on the robust order-statistic theory and the minimization of the weighted distance function to other input samples. The proposed method can be designed to perform a variety of filtering operations including previously developed filtering techniques such as vector median, basic vector directional filter, directional distance filter, weighted vector median filters and weighted directional filters. A wide range of filtering operations is guaranteed by the filter structure with two independent weight vectors for angular and distance domains of the vector space. In order to adapt the filter parameters to varying signal and noise statistics, we provide also the generalized optimization algorithms taking the advantage of the weighted median filters and the relationship between standard median filter and vector median filter. Thus, we can deal with both statistical and deterministic aspects of the filter design process. It will be shown that the proposed method holds the required properties such as the capability of modelling the underlying system in the application at hand, the robustness with respect to errors in the model of underlying system, the availability of the training procedure and finally, the simplicity of filter representation, analysis, design and implementation. Simulation studies also indicate that the new filters are computationally attractive and have excellent performance in environments corrupted by bit errors and impulsive noise.

Symbolic computer vector analysis

Science.gov (United States)

Stoutemyer, D. R.

1977-01-01

A MACSYMA program is described which performs symbolic vector algebra and vector calculus. The program can combine and simplify symbolic expressions including dot products and cross products, together with the gradient, divergence, curl, and Laplacian operators. The distribution of these operators over sums or products is under user control, as are various other expansions, including expansion into components in any specific orthogonal coordinate system. There is also a capability for deriving the scalar or vector potential of a vector field. Examples include derivation of the partial differential equations describing fluid flow and magnetohydrodynamics, for 12 different classic orthogonal curvilinear coordinate systems.

Vector continued fractions using a generalized inverse

International Nuclear Information System (INIS)

Haydock, Roger; Nex, C M M; Wexler, Geoffrey

2004-01-01

A real vector space combined with an inverse (involution) for vectors is sufficient to define a vector continued fraction whose parameters consist of vector shifts and changes of scale. The choice of sign for different components of the vector inverse permits construction of vector analogues of the Jacobi continued fraction. These vector Jacobi fractions are related to vector and scalar-valued polynomial functions of the vectors, which satisfy recurrence relations similar to those of orthogonal polynomials. The vector Jacobi fraction has strong convergence properties which are demonstrated analytically, and illustrated numerically

The Cross Product of Two Vectors Is Not Just Another Vector--A Major Misconception Being Perpetuated in Calculus and Vector Analysis Textbooks.

Science.gov (United States)

Elk, Seymour B.

1997-01-01

Suggests that the cross product of two vectors can be more easily and accurately explained by starting from the perspective of dyadics because then the concept of vector multiplication has a simple geometrical picture that encompasses both the dot and cross products in any number of dimensions in terms of orthogonal unit vector components. (AIM)

Major vectors and vector-borne diseases in small ruminants in Ethiopia: A systematic review.

Science.gov (United States)

Asmare, Kassahun; Abayneh, Takele; Sibhat, Berhanu; Shiferaw, Dessie; Szonyi, Barbara; Krontveit, Randi I; Skjerve, Eystein; Wieland, Barbara

2017-06-01

Vector-borne diseases are among major health constraints of small ruminant in Ethiopia. While various studies on single vector-borne diseases or presence of vectors have been conducted, no summarized evidence is available on the occurrence of these diseases and the related vectors. This systematic literature review provides a comprehensive summary on major vectors and vector-borne diseases in small ruminants in Ethiopia. Search for published and unpublished literature was conducted between 8th of January and 25th of June 2015. The search was both manual and electronic. The databases used in electronic search were PubMed, Web of Science, CAB Direct and AJOL. For most of the vector-borne diseases, the summary was limited to narrative synthesis due to lack of sufficient data. Meta-analysis was computed for trypanosomosis and dermatophilosis while meta-regression and sensitivity analysis was done only for trypanososmosis due to lack of sufficient reports on dermatophilosis. Owing emphasis to their vector role, ticks and flies were summarized narratively at genera/species level. In line with inclusion criteria, out of 106 initially identified research reports 43 peer-reviewed articles passed the quality assessment. Data on 7 vector-borne diseases were extracted at species and region level from each source. Accordingly, the pooled prevalence estimate of trypanosomosis was 3.7% with 95% confidence interval (CI) 2.8, 4.9), while that of dermatophilosis was 3.1% (95% CI: 1.6, 6.0). The in-between study variance noted for trypanosomosis was statistically significant (pparasitic presence in blood was documented for babesiosis (3.7% in goats); and anaplasmosis (3.9% in sheep). Serological evidence was retrieved for bluetongue ranging from 34.1% to 46.67% in sheep, and coxiellosis was 10.4% in goats. There was also molecular evidence on the presence of theileriosis in sheep (93%, n=160) and goats (1.9%, n=265). Regarding vectors of veterinary importance, 14 species of ticks in

GPU Accelerated Vector Median Filter

Science.gov (United States)

Aras, Rifat; Shen, Yuzhong

2011-01-01

Noise reduction is an important step for most image processing tasks. For three channel color images, a widely used technique is vector median filter in which color values of pixels are treated as 3-component vectors. Vector median filters are computationally expensive; for a window size of n x n, each of the n(sup 2) vectors has to be compared with other n(sup 2) - 1 vectors in distances. General purpose computation on graphics processing units (GPUs) is the paradigm of utilizing high-performance many-core GPU architectures for computation tasks that are normally handled by CPUs. In this work. NVIDIA's Compute Unified Device Architecture (CUDA) paradigm is used to accelerate vector median filtering. which has to the best of our knowledge never been done before. The performance of GPU accelerated vector median filter is compared to that of the CPU and MPI-based versions for different image and window sizes, Initial findings of the study showed 100x improvement of performance of vector median filter implementation on GPUs over CPU implementations and further speed-up is expected after more extensive optimizations of the GPU algorithm .

Effects of Climate and Climate Change on Vectors and Vector-Borne Diseases: Ticks Are Different.

Science.gov (United States)

Ogden, Nick H; Lindsay, L Robbin

2016-08-01

There has been considerable debate as to whether global risk from vector-borne diseases will be impacted by climate change. This has focussed on important mosquito-borne diseases that are transmitted by the vectors from infected to uninfected humans. However, this debate has mostly ignored the biological diversity of vectors and vector-borne diseases. Here, we review how climate and climate change may impact those most divergent of arthropod disease vector groups: multivoltine insects and hard-bodied (ixodid) ticks. We contrast features of the life cycles and behaviour of these arthropods, and how weather, climate, and climate change may have very different impacts on the spatiotemporal occurrence and abundance of vectors, and the pathogens they transmit. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Hierarchal scalar and vector tetrahedra

International Nuclear Information System (INIS)

Webb, J.P.; Forghani, B.

1993-01-01

A new set of scalar and vector tetrahedral finite elements are presented. The elements are hierarchal, allowing mixing of polynomial orders; scalar orders up to 3 and vector orders up to 2 are defined. The vector elements impose tangential continuity on the field but not normal continuity, making them suitable for representing the vector electric or magnetic field. Further, the scalar and vector elements are such that they can easily be used in the same mesh, a requirement of many quasi-static formulations. Results are presented for two 50 Hz problems: the Bath Cube, and TEAM Problem 7

Generation of arbitrary vector fields based on a pair of orthogonal elliptically polarized base vectors.

Science.gov (United States)

Xu, Danfeng; Gu, Bing; Rui, Guanghao; Zhan, Qiwen; Cui, Yiping

2016-02-22

We present an arbitrary vector field with hybrid polarization based on the combination of a pair of orthogonal elliptically polarized base vectors on the Poincaré sphere. It is shown that the created vector field is only dependent on the latitude angle 2χ but is independent on the longitude angle 2ψ on the Poincaré sphere. By adjusting the latitude angle 2χ, which is related to two identical waveplates in a common path interferometric arrangement, one could obtain arbitrary type of vector fields. Experimentally, we demonstrate the generation of such kind of vector fields and confirm the distribution of state of polarization by the measurement of Stokes parameters. Besides, we investigate the tight focusing properties of these vector fields. It is found that the additional degree of freedom 2χ provided by arbitrary vector field with hybrid polarization allows one to control the spatial structure of polarization and to engineer the focusing field.

Calculus with vectors

CERN Document Server

Treiman, Jay S

2014-01-01

Calculus with Vectors grew out of a strong need for a beginning calculus textbook for undergraduates who intend to pursue careers in STEM. fields. The approach introduces vector-valued functions from the start, emphasizing the connections between one-variable and multi-variable calculus. The text includes early vectors and early transcendentals and includes a rigorous but informal approach to vectors. Examples and focused applications are well presented along with an abundance of motivating exercises. All three-dimensional graphs have rotatable versions included as extra source materials and may be freely downloaded and manipulated with Maple Player; a free Maple Player App is available for the iPad on iTunes. The approaches taken to topics such as the derivation of the derivatives of sine and cosine, the approach to limits, and the use of "tables" of integration have been modified from the standards seen in other textbooks in order to maximize the ease with which students may comprehend the material. Additio...

Test of understanding of vectors: A reliable multiple-choice vector concept test

Science.gov (United States)

Barniol, Pablo; Zavala, Genaro

2014-06-01

In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended problems in which a total of 2067 students participated. Using this taxonomy, we then designed a 20-item multiple-choice test [Test of understanding of vectors (TUV)] and administered it in English to 423 students who were completing the required sequence of introductory physics courses at a large private Mexican university. We evaluated the test's content validity, reliability, and discriminatory power. The results indicate that the TUV is a reliable assessment tool. We also conducted a detailed analysis of the students' understanding of the vector concepts evaluated in the test. The TUV is included in the Supplemental Material as a resource for other researchers studying vector learning, as well as instructors teaching the material.

ESTUDO DO APROVEITAMENTO DAS VÍSCERAS DOS MOLUSCOS ESCARGOT (Achatina fulica E ARUÁ (Pomacea lineata PARA INCORPORAÇÃO EM RAÇÃO ANIMAL

Directory of Open Access Journals (Sweden)

S. E. R. BARBOZA

2008-09-01

Full Text Available

O objetivo deste trabalho foi estudar o aproveitamento das vísceras - subprodutos, dos moluscos escargot e aruá. As vísceras foram processadas na forma de farinha e suas características físico-químicas (composição centesimal, cálcio, fósforo, digestibilidade em pepsina, índice de acidez e microbiológicas (Salmonella sp foram comparadas aos padrões de qualidades exigidas pela Legislação (6.198, de 26/12/74, e o Decreto 76.986, de 06/01/76 do Ministério da Agricultura e Abastecimento para a comercialização de produtos destinados à alimentação animal. Os resultados obtidos permitiram verificar que as farinhas de vísceras de ambas espécies podem ser utilizadas como matérias primas, constituindo ótimas fontes de nutrientes para a incorporação em rações animais.

Leishmaniasis vector behaviour in Kenya

International Nuclear Information System (INIS)

Mutinga, M.J.

1980-01-01

Leishmaniasis in Kenya exists in two forms: cutaneous and visceral. The vectors of visceral leishmaniasis have been the subject of investigation by various researchers since World War II, when the outbreak of the disease was first noticed. The vectors of cutaneous leishmaniasis were first worked on only a decade ago after the discovery of the disease focus in Mt. Elgon. The vector behaviour of these diseases, namely Phlebotomus pedifer, the vector of cutaneous leishmaniasis, and Phlebotomus martini, the vector of visceral leishmaniasis, are discussed in detail. P. pedifer has been found to breed and bite inside caves, whereas P. martini mainly bites inside houses. (author)

Ciclo reproductivo del molusco Atrina maura (Pterioidea: Pinnidae en un sistema lagunar costero, al sur del Pacífico tropical mexicano

Directory of Open Access Journals (Sweden)

Claudia Angel-Pérez

2007-12-01

Full Text Available De febrero de 1997 a febrero de 1998, se recolectaron mensualmente muestras aleatorias del molusco Atrina maura en el sistema lagunar Corralero-Alotengo, Oaxaca, México. Se extrajeron las partes blandas para lavarlas in situ y fijarlas en solución Davison. En el laboratorio se pesaron para obtener los índices gonadosomático (IGS y de rendimiento muscular (IRM, y mediante cortes histológico de las gónadas se caracterizó el ciclo reproductivo. Esta población se reproduce casi todo el año, con dos periodos reproductivos importantes: uno de abril a julio y otro de octubre a noviembre, y una sola época de reposo, en agosto y septiembre. El ciclo reproductivo tiene una relación directa con el IGS e inversa con el IRM. Hay evidencias de una relación estrecha de las época de desove y postdesove con la temperatura del agua (R = 0.991, p 0.002. Las hembras predominaron casi todo el año, aunque esta proporción solo tuvo diferencias estadísticamente significativas en noviembre (X²: p= 0.05Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae in a coastal lagoon system of the Mexican South Pacific. From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSI and the muscle yield index (MYI were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSI and a reverse relationship with the MYI. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p = 0.002. Females dominate numerically

Learning with LOGO: Logo and Vectors.

Science.gov (United States)

Lough, Tom; Tipps, Steve

1986-01-01

This is the first of a two-part series on the general concept of vector space. Provides tool procedures to allow investigation of vector properties, vector addition and subtraction, and X and Y components. Lists several sources of additional vector ideas. (JM)

Identification and characterization of potential NBS-encoding resistance genes and induction kinetics of a putative candidate gene associated with downy mildew resistance in Cucumis

Directory of Open Access Journals (Sweden)

Wan Hongjian

2010-08-01

Full Text Available Abstract Background Due to the variation and mutation of the races of Pseudoperonospora cubensis, downy mildew has in recent years become the most devastating leaf disease of cucumber worldwide. Novel resistance to downy mildew has been identified in the wild Cucumis species, C. hystrix Chakr. After the successful hybridization between C. hystrix and cultivated cucumber (C. sativus L., an introgression line (IL5211S was identified as highly resistant to downy mildew. Nucleotide-binding site and leucine-rich repeat (NBS-LRR genes are the largest class of disease resistance genes cloned from plant with highly conserved domains, which can be used to facilitate the isolation of candidate genes associated with downy mildew resistance in IL5211S. Results Degenerate primers that were designed based on the conserved motifs in the NBS domain of resistance (R proteins were used to isolate NBS-type sequences from IL5211S. A total of 28 sequences were identified and named as cucumber (C. sativus = CS resistance gene analogs as CSRGAs. Polygenetic analyses separated these sequences into four different classes. Quantitative real-time polymerase chain reaction (qRT-PCR analysis showed that these CSRGAs expressed at different levels in leaves, roots, and stems. In addition, introgression from C. hystrix induced expression of the partial CSRGAs in cultivated cucumber, especially CSRGA23, increased four-fold when compared to the backcross parent CC3. Furthermore, the expression of CSRGA23 under P. cubensis infection and abiotic stresses was also analyzed at different time points. Results showed that the P. cubensis treatment and four tested abiotic stimuli, MeJA, SA, ABA, and H2O2, triggered a significant induction of CSRGA23 within 72 h of inoculation. The results indicate that CSRGA23 may play a critical role in protecting cucumber against P. cubensis through a signaling the pathway triggered by these molecules. Conclusions Four classes of NBS-type RGAs were

Strangeness Vector and Axial-Vector Form Factors of the Nucleon

Directory of Open Access Journals (Sweden)

Pate Stephen

2014-03-01

Full Text Available A revised global fit of electroweak ep and vp elastic scattering data has been performed, with the goal of determining the strange quark contribution to the vector and axial-vector form factors of the nucleon in the momentum-transfer range 0 < Q2 < 1 GeV2. The two vector (electric and magnetic form factors GsE(Q2 and GsM(Q2 are strongly constrained by ep elastic scattering data, while the major source of information on the axial-vector form factor GsA(Q2 is vp scattering data. Combining the two kinds of data into a single global fit makes possible additional precision in the determination of these form factors, and provides a unique way to determine the strange quark contribution to the nucleon spin, ΔS , independently of leptonic deep-inelastic scattering. The fit makes use of data from the BNL-E734, SAMPLE, HAPPEx, G0, and PVA4 experiments; we will also compare the result of the fit with recent data from MiniBooNE, and anticipate how this fit can be improved when new data from MicroBooNE become available.

Multi-task Vector Field Learning.

Science.gov (United States)

Lin, Binbin; Yang, Sen; Zhang, Chiyuan; Ye, Jieping; He, Xiaofei

2012-01-01

Multi-task learning (MTL) aims to improve generalization performance by learning multiple related tasks simultaneously and identifying the shared information among tasks. Most of existing MTL methods focus on learning linear models under the supervised setting. We propose a novel semi-supervised and nonlinear approach for MTL using vector fields. A vector field is a smooth mapping from the manifold to the tangent spaces which can be viewed as a directional derivative of functions on the manifold. We argue that vector fields provide a natural way to exploit the geometric structure of data as well as the shared differential structure of tasks, both of which are crucial for semi-supervised multi-task learning. In this paper, we develop multi-task vector field learning (MTVFL) which learns the predictor functions and the vector fields simultaneously. MTVFL has the following key properties. (1) The vector fields MTVFL learns are close to the gradient fields of the predictor functions. (2) Within each task, the vector field is required to be as parallel as possible which is expected to span a low dimensional subspace. (3) The vector fields from all tasks share a low dimensional subspace. We formalize our idea in a regularization framework and also provide a convex relaxation method to solve the original non-convex problem. The experimental results on synthetic and real data demonstrate the effectiveness of our proposed approach.

Enhancing poxvirus vectors vaccine immunogenicity.

Science.gov (United States)

García-Arriaza, Juan; Esteban, Mariano

2014-01-01

Attenuated recombinant poxvirus vectors expressing heterologous antigens from pathogens are currently at various stages in clinical trials with the aim to establish their efficacy. This is because these vectors have shown excellent safety profiles, significant immunogenicity against foreign expressed antigens and are able to induce protective immune responses. In view of the limited efficacy triggered by some poxvirus strains used in clinical trials (i.e, ALVAC in the RV144 phase III clinical trial for HIV), and of the restrictive replication capacity of the highly attenuated vectors like MVA and NYVAC, there is a consensus that further improvements of these vectors should be pursuit. In this review we considered several strategies that are currently being implemented, as well as new approaches, to improve the immunogenicity of the poxvirus vectors. This includes heterologous prime/boost protocols, use of co-stimulatory molecules, deletion of viral immunomodulatory genes still present in the poxvirus genome, enhancing virus promoter strength, enhancing vector replication capacity, optimizing expression of foreign heterologous sequences, and the combined use of adjuvants. An optimized poxvirus vector triggering long-lasting immunity with a high protective efficacy against a selective disease should be sought.

Stable piecewise polynomial vector fields

Directory of Open Access Journals (Sweden)

Claudio Pessoa

2012-09-01

Full Text Available Let $N={y>0}$ and $S={y<0}$ be the semi-planes of $mathbb{R}^2$ having as common boundary the line $D={y=0}$. Let $X$ and $Y$ be polynomial vector fields defined in $N$ and $S$, respectively, leading to a discontinuous piecewise polynomial vector field $Z=(X,Y$. This work pursues the stability and the transition analysis of solutions of $Z$ between $N$ and $S$, started by Filippov (1988 and Kozlova (1984 and reformulated by Sotomayor-Teixeira (1995 in terms of the regularization method. This method consists in analyzing a one parameter family of continuous vector fields $Z_{epsilon}$, defined by averaging $X$ and $Y$. This family approaches $Z$ when the parameter goes to zero. The results of Sotomayor-Teixeira and Sotomayor-Machado (2002 providing conditions on $(X,Y$ for the regularized vector fields to be structurally stable on planar compact connected regions are extended to discontinuous piecewise polynomial vector fields on $mathbb{R}^2$. Pertinent genericity results for vector fields satisfying the above stability conditions are also extended to the present case. A procedure for the study of discontinuous piecewise vector fields at infinity through a compactification is proposed here.

Transversals of Complex Polynomial Vector Fields

DEFF Research Database (Denmark)

Dias, Kealey

Vector fields in the complex plane are defined by assigning the vector determined by the value P(z) to each point z in the complex plane, where P is a polynomial of one complex variable. We consider special families of so-called rotated vector fields that are determined by a polynomial multiplied...... by rotational constants. Transversals are a certain class of curves for such a family of vector fields that represent the bifurcation states for this family of vector fields. More specifically, transversals are curves that coincide with a homoclinic separatrix for some rotation of the vector field. Given...... a concrete polynomial, it seems to take quite a bit of work to prove that it is generic, i.e. structurally stable. This has been done for a special class of degree d polynomial vector fields having simple equilibrium points at the d roots of unity, d odd. In proving that such vector fields are generic...

Vector optimization set-valued and variational analysis

CERN Document Server

Chen, Guang-ya; Yang, Xiaogi

2005-01-01

This book is devoted to vector or multiple criteria approaches in optimization. Topics covered include: vector optimization, vector variational inequalities, vector variational principles, vector minmax inequalities and vector equilibrium problems. In particular, problems with variable ordering relations and set-valued mappings are treated. The nonlinear scalarization method is extensively used throughout the book to deal with various vector-related problems. The results presented are original and should be interesting to researchers and graduates in applied mathematics and operations research

Implicit Real Vector Automata

Directory of Open Access Journals (Sweden)

Jean-François Degbomont

2010-10-01

Full Text Available This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data structure for representing such sets, based on an implicit and concise encoding of a known structure, the Real Vector Automaton. The resulting formalism provides a canonical representation of polyhedra, is closed under Boolean operators, and admits an efficient decision procedure for testing the membership of a vector.

Vectoring of parallel synthetic jets

Science.gov (United States)

Berk, Tim; Ganapathisubramani, Bharathram; Gomit, Guillaume

2015-11-01

A pair of parallel synthetic jets can be vectored by applying a phase difference between the two driving signals. The resulting jet can be merged or bifurcated and either vectored towards the actuator leading in phase or the actuator lagging in phase. In the present study, the influence of phase difference and Strouhal number on the vectoring behaviour is examined experimentally. Phase-locked vorticity fields, measured using Particle Image Velocimetry (PIV), are used to track vortex pairs. The physical mechanisms that explain the diversity in vectoring behaviour are observed based on the vortex trajectories. For a fixed phase difference, the vectoring behaviour is shown to be primarily influenced by pinch-off time of vortex rings generated by the synthetic jets. Beyond a certain formation number, the pinch-off timescale becomes invariant. In this region, the vectoring behaviour is determined by the distance between subsequent vortex rings. We acknowledge the financial support from the European Research Council (ERC grant agreement no. 277472).

Vectorization in quantum chemistry

International Nuclear Information System (INIS)

Saunders, V.R.

1987-01-01

It is argued that the optimal vectorization algorithm for many steps (and sub-steps) in a typical ab initio calculation of molecular electronic structure is quite strongly dependent on the target vector machine. Details such as the availability (or lack) of a given vector construct in the hardware, vector startup times and asymptotic rates must all be considered when selecting the optimal algorithm. Illustrations are drawn from: gaussian integral evaluation, fock matrix construction, 4-index transformation of molecular integrals, direct-CI methods, the matrix multiply operation. A cross comparison of practical implementations on the CDC Cyber 205, the Cray-IS and Cray-XMP machines is presented. To achieve portability while remaining optimal on a wide range of machines it is necessary to code all available algorithms in a machine independent manner, and to select the appropriate algorithm using a procedure which is based on machine dependent parameters. Most such parameters concern the timing of certain vector loop kernals, which can usually be derived from a 'bench-marking' routine executed prior to the calculation proper

Properties of vector and axial-vector mesons from a generalized Nambu-Jona-Lasinio model

International Nuclear Information System (INIS)

Bernard, V.; Meissner, U.G.; Massachusetts Inst. of Tech., Cambridge; Massachusetts Inst. of Tech., Cambridge

1988-01-01

We construct a generalized Nambu-Jona-Lasinio lagrangian including scalar, pseudoscalar, vector and axial-vector mesons. We specialize to the two-flavor case. The properties of the structured vacuum as well as meson masses and coupling constants are calculated giving an overall agreement within 20% of the experimental data. We investigate the meson properties at finite density. In contrast to the mass of the scalar σ-meson, which decreases sharply with increasing density, the vector meson masses are almost independent of density. Furthermore, the vector-meson-quark coupling constants are also stable against density changes. We point out that these results imply a softening of the nuclear equation of state at high densities. Furthermore, we discuss the breakdown of the KFSR relation on the quark level as well as other deviations from phenomenological concepts such as universality and vector meson dominance. (orig.)

Vector geometry

CERN Document Server

Robinson, Gilbert de B

2011-01-01

This brief undergraduate-level text by a prominent Cambridge-educated mathematician explores the relationship between algebra and geometry. An elementary course in plane geometry is the sole requirement for Gilbert de B. Robinson's text, which is the result of several years of teaching and learning the most effective methods from discussions with students. Topics include lines and planes, determinants and linear equations, matrices, groups and linear transformations, and vectors and vector spaces. Additional subjects range from conics and quadrics to homogeneous coordinates and projective geom

Electroproduction and photoproduction of vector mesons and generalized vector meson dominance

International Nuclear Information System (INIS)

Fraas, H.; Kuroda, M.

1977-05-01

Using generalized vector meson dominance, electro- and photoproduction of vector mesons is studied. The unnatural parity exchange part of ω(1.2) production is estimated to be about one fourth of that of ω-production. The off diagonal transition model suggests the suppression of diffractive rho(1.2) and ω(1.2) production. (orig.) [de

Vector (two-dimensional) magnetic phenomena

International Nuclear Information System (INIS)

Enokizono, Masato

2002-01-01

In this paper, some interesting phenomena were described from the viewpoint of two-dimensional magnetic property, which is reworded with the vector magnetic property. It shows imperfection of conventional magnetic property and some interested phenomena were discovered, too. We found magnetic materials had the strong nonlinearity both magnitude and spatial phase due to the relationship between the magnetic field strength H-vector and the magnetic flux density B-vector. Therefore, magnetic properties should be defined as the vector relationship. Furthermore, the new Barukhausen signal was observed under rotating flux. (Author)

Quark-gluon plasma tomography by vector mesons

International Nuclear Information System (INIS)

Lovas, I.; Schram, Zs.; Csernai, L.P.; Hungarian Academy of Sciences, Budapest; Nyiri, A.

2001-01-01

The fireball formed in a heavy ion collision is characterized by the impact parameter vector b-vector, which can be determined from the multiplicity and the angular distribution of the reaction products. By appropriate rotations the b-vector vectors of each collision can be aligned into a fixed direction. Using the measured values of the momentum distributions independent integral equations can be formulated for the unknown emission densities (E M (r-vector)) and for the unknown absorption densities (Δμ(r-vector)) of the different vector mesons. (author)

Vector superconductivity in cosmic strings

International Nuclear Information System (INIS)

Dvali, G.R.; Mahajan, S.M.

1992-03-01

We argue that in most realistic cases, the usual Witten-type bosonic superconductivity of the cosmic string is automatically (independent of the existence of superconducting currents) accompanied by the condensation of charged gauge vector bosons in the core giving rise to a new vector type superconductivity. The value of the charged vector condensate is related with the charged scalar expectation value, and vanishes only if the latter goes to zero. The mechanism for the proposed vector superconductivity, differing fundamentally from those in the literature, is delineated using the simplest realistic example of the two Higgs doublet standard model interacting with the extra cosmic string. It is shown that for a wide range of parameters, for which the string becomes scalarly superconducting, W boson condensates (the sources of vector superconductivity) are necessarily excited. (author). 14 refs

Brane vector phenomenology

International Nuclear Information System (INIS)

Clark, T.E.; Love, S.T.; Nitta, Muneto; Veldhuis, T. ter; Xiong, C.

2009-01-01

Local oscillations of the brane world are manifested as massive vector fields. Their coupling to the Standard Model can be obtained using the method of nonlinear realizations of the spontaneously broken higher-dimensional space-time symmetries, and to an extent, are model independent. Phenomenological limits on these vector field parameters are obtained using LEP collider data and dark matter constraints

Distribution of Brugia malayi larvae and DNA in vector and non-vector mosquitoes: implications for molecular diagnostics

Directory of Open Access Journals (Sweden)

Christensen Bruce M

2009-11-01

Full Text Available Abstract Background The purpose of this study was to extend prior studies of molecular detection of Brugia malayi DNA in vector (Aedes aegypti- Liverpool and non-vector (Culex pipiens mosquitoes at different times after ingestion of infected blood. Results Parasite DNA was detected over a two week time course in 96% of pooled thoraces of vector mosquitoes. In contrast, parasite DNA was detected in only 24% of thorax pools from non-vectors; parasite DNA was detected in 56% of midgut pools and 47% of abdomen pools from non-vectors. Parasite DNA was detected in vectors in the head immediately after the blood meal and after 14 days. Parasite DNA was also detected in feces and excreta of the vector and non-vector mosquitoes which could potentially confound results obtained with field samples. However, co-housing experiments failed to demonstrate transfer of parasite DNA from infected to non-infected mosquitoes. Parasites were also visualized in mosquito tissues by immunohistololgy using an antibody to the recombinant filarial antigen Bm14. Parasite larvae were detected consistently after mf ingestion in Ae. aegypti- Liverpool. Infectious L3s were seen in the head, thorax and abdomen of vector mosquitoes 14 days after Mf ingestion. In contrast, parasites were only detected by histology shortly after the blood meal in Cx. pipiens, and these were not labeled by the antibody. Conclusion This study provides new information on the distribution of filarial parasites and parasite DNA in vector and non-vector mosquitoes. This information should be useful for those involved in designing and interpreting molecular xenomonitoring studies.

Insecticide resistance in disease vectors from Mayotte: an opportunity for integrated vector management.

Science.gov (United States)

Pocquet, Nicolas; Darriet, Frédéric; Zumbo, Betty; Milesi, Pascal; Thiria, Julien; Bernard, Vincent; Toty, Céline; Labbé, Pierrick; Chandre, Fabrice

2014-07-01

Mayotte, a small island in the Indian Ocean, has been affected for many years by vector-borne diseases. Malaria, Bancroftian filariasis, dengue, chikungunya and Rift Valley fever have circulated or still circulate on the island. They are all transmitted by Culicidae mosquitoes. To limit the impact of these diseases on human health, vector control has been implemented for more than 60 years on Mayotte. In this study, we assessed the resistance levels of four major vector species (Anopheles gambiae, Culex pipiens quinquefasciatus, Aedes aegypti and Aedes albopictus) to two types of insecticides: i) the locally currently-used insecticides (organophosphates, pyrethroids) and ii) alternative molecules that are promising for vector control and come from different insecticide families (bacterial toxins or insect growth regulators). When some resistance was found to one of these insecticides, we characterized the mechanisms involved. Larval and adult bioassays were used to evaluate the level of resistance. When resistance was found, we tested for the presence of metabolic resistance through detoxifying enzyme activity assays, or for target-site mutations through molecular identification of known resistance alleles. Resistance to currently-used insecticides varied greatly between the four vector species. While no resistance to any insecticides was found in the two Aedes species, bioassays confirmed multiple resistance in Cx. p. quinquefasciatus (temephos: ~ 20 fold and deltamethrin: only 10% mortality after 24 hours). In An. gambiae, resistance was scarce: only a moderate resistance to temephos was found (~5 fold). This resistance appears to be due only to carboxyl-esterase overexpression and not to target modification. Finally, and comfortingly, none of the four species showed resistance to any of the new insecticides. The low resistance observed in Mayotte's main disease vectors is particularly interesting, because it leaves a range of tools useable by vector control

A comparison of foamy and lentiviral vector genotoxicity in SCID-repopulating cells shows foamy vectors are less prone to clonal dominance

Directory of Open Access Journals (Sweden)

Elizabeth M Everson

2016-01-01

Full Text Available Hematopoietic stem cell (HSC gene therapy using retroviral vectors has immense potential, but vector-mediated genotoxicity limits use in the clinic. Lentiviral vectors are less genotoxic than gammaretroviral vectors and have become the vector of choice in clinical trials. Foamy retroviral vectors have a promising integration profile and are less prone to read-through transcription than gammaretroviral or lentiviral vectors. Here, we directly compared the safety and efficacy of foamy vectors to lentiviral vectors in human CD34+ repopulating cells in immunodeficient mice. To increase their genotoxic potential, foamy and lentiviral vectors with identical transgene cassettes with a known genotoxic spleen focus forming virus promoter were used. Both vectors resulted in efficient marking in vivo and a total of 825 foamy and 460 lentiviral vector unique integration sites were recovered in repopulating cells 19 weeks after transplantation. Foamy vector proviruses were observed less often near RefSeq gene and proto-oncogene transcription start sites than lentiviral vectors. The foamy vector group were also more polyclonal with fewer dominant clones (two out of six mice than the lentiviral vector group (eight out of eight mice, and only lentiviral vectors had integrants near known proto-oncogenes in dominant clones. Our data further support the relative safety of foamy vectors for HSC gene therapy.

Tensor Calculus: Unlearning Vector Calculus

Science.gov (United States)

Lee, Wha-Suck; Engelbrecht, Johann; Moller, Rita

2018-01-01

Tensor calculus is critical in the study of the vector calculus of the surface of a body. Indeed, tensor calculus is a natural step-up for vector calculus. This paper presents some pitfalls of a traditional course in vector calculus in transitioning to tensor calculus. We show how a deeper emphasis on traditional topics such as the Jacobian can…

Vector mesons on the light front

International Nuclear Information System (INIS)

Naito, K.; Maedan, S.; Itakura, K.

2004-01-01

We apply the light-front quantization to the Nambu-Jona-Lasinio model with the vector interaction, and compute vector meson's mass and light-cone wavefunction in the large N limit. Following the same procedure as in the previous analyses for scalar and pseudo-scalar mesons, we derive the bound-state equations of a qq-bar system in the vector channel. We include the lowest order effects of the vector interaction. The resulting transverse and longitudinal components of the bound-state equation look different from each other. But eventually after imposing an appropriate cutoff, one finds these two are identical, giving the same mass and the same (spin-independent) light-cone wavefunction. Mass of the vector meson decreases as one increases the strength of the vector interaction

Does the delta quench Gamow-Teller strength in (p,n)- and (p vector,p vector')-reactions

International Nuclear Information System (INIS)

Osterfeld, F.; Schulte, A.; Udagawa, T.; Yabe, M.

1986-01-01

Microscopic analyses of complete forward angle intermediate energy (p,n)-, ( 3 He,t)- and (p vector,p vector')-spin-flip spectra are presented for the reactions 90 Zr(p,n), 90 Zr( 3 He,t) and 90 Zr(p vector,p vector'). It is shown that the whole spectra up to high excitation energies (E X ∝50 MeV) are the result of correlated one-particle-one-hole (1p1h) spin-isospin transitions only. The spectra reflect, therefore, the linear spin-isospin response of the target nucleus to the probing external hadronic fields. Our results suggest that the measured (p,n)-, ( 3 He,t)- and (p vector,p vector')-cross sections are compatible with the transition strength predictions as obtained from random phase approximation (RPA) calculations. This means that the Δ isobar quenching mechanism is likely to be rather small. (orig.)

On the Vectorization of FIR Filterbanks

Directory of Open Access Journals (Sweden)

Barbedo Jayme Garcia Arnal

2007-01-01

Full Text Available This paper presents a vectorization technique to implement FIR filterbanks. The word vectorization, in the context of this work, refers to a strategy in which all iterative operations are replaced by equivalent vector and matrix operations. This approach allows that the increasing parallelism of the most recent computer processors and systems be properly explored. The vectorization techniques are applied to two kinds of FIR filterbanks (conventional and recursi ve, and are presented in such a way that they can be easily extended to any kind of FIR filterbanks. The vectorization approach is compared to other kinds of implementation that do not explore the parallelism, and also to a previous FIR filter vectorization approach. The tests were performed in Matlab and , in order to explore different aspects of the proposed technique.

On the Vectorization of FIR Filterbanks

Directory of Open Access Journals (Sweden)

Amauri Lopes

2007-01-01

Full Text Available This paper presents a vectorization technique to implement FIR filterbanks. The word vectorization, in the context of this work, refers to a strategy in which all iterative operations are replaced by equivalent vector and matrix operations. This approach allows that the increasing parallelism of the most recent computer processors and systems be properly explored. The vectorization techniques are applied to two kinds of FIR filterbanks (conventional and recursi ve, and are presented in such a way that they can be easily extended to any kind of FIR filterbanks. The vectorization approach is compared to other kinds of implementation that do not explore the parallelism, and also to a previous FIR filter vectorization approach. The tests were performed in Matlab and C, in order to explore different aspects of the proposed technique.

Two-hadron saturation for the pseudoscalar-vector-vector correlator and phenomenological applications

Energy Technology Data Exchange (ETDEWEB)

Husek, Tomas [Charles University, Faculty of Mathematics and Physics, Institute of Particle and Nuclear Physics, Prague 8 (Czech Republic); Leupold, Stefan [Uppsala Universitet, Institutionen foer Fysik och Astronomi, Box 516, Uppsala (Sweden)

2015-12-15

The pseudoscalar-vector-vector correlator is constructed using two meson multiplets in the vector and two in the pseudoscalar channel. The parameters are constrained by the operator product expansion at leading order where two or all three momenta are considered as large. Demanding in addition the Brodsky-Lepage limit one obtains (in the chiral limit) pion-vector-vector (πVV) correlator with only one free parameter. The singly virtual pion transition form factor F{sub π{sup 0}γγ*} and the decay width of ω → π{sup 0}γ are independent of this parameter and can serve as cross-checks of the results. The free parameter is determined from a fit of the ω-π transition form factor F{sub π{sup 0}ωγ*}. The resulting πVV correlator is used to calculate the decay widths ω → π{sup 0}e{sup +}e{sup -} and ω → π{sup 0}μ{sup +}μ{sup -} and finally the widths of the rare decay π{sup 0} → e{sup +}e{sup -} and of the Dalitz decay π{sup 0} → e{sup +}e{sup -}γ. Incorporating radiative QED corrections the calculations of π{sup 0} decays are compared to the KTeV results. We find a deviation of 2 σ or less for the rare pion decay. (orig.)

Vector borne diseases

OpenAIRE

Melillo Fenech, Tanya

2010-01-01

A vector-borne disease is one in which the pathogenic microorganism is transmitted from an infected individual to another individual by an arthropod or other agent. The transmission depends upon the attributes and requirements of at least three different Iiving organisms : the pathologic agent which is either a virus, protozoa, bacteria or helminth (worm); the vector, which is commonly an arthropod such as ticks or mosquitoes; and the human host.

Scanning vector Hall probe microscopy

International Nuclear Information System (INIS)

Cambel, V.; Gregusova, D.; Fedor, J.; Kudela, R.; Bending, S.J.

2004-01-01

We have developed a scanning vector Hall probe microscope for mapping magnetic field vector over magnetic samples. The microscope is based on a micromachined Hall sensor and the cryostat with scanning system. The vector Hall sensor active area is ∼5x5 μm 2 . It is realized by patterning three Hall probes on the tilted faces of GaAs pyramids. Data from these 'tilted' Hall probes are used to reconstruct the full magnetic field vector. The scanning area of the microscope is 5x5 mm 2 , space resolution 2.5 μm, field resolution ∼1 μT Hz -1/2 at temperatures 10-300 K

Non-coaxial superposition of vector vortex beams.

Science.gov (United States)

Aadhi, A; Vaity, Pravin; Chithrabhanu, P; Reddy, Salla Gangi; Prabakar, Shashi; Singh, R P

2016-02-10

Vector vortex beams are classified into four types depending upon spatial variation in their polarization vector. We have generated all four of these types of vector vortex beams by using a modified polarization Sagnac interferometer with a vortex lens. Further, we have studied the non-coaxial superposition of two vector vortex beams. It is observed that the superposition of two vector vortex beams with same polarization singularity leads to a beam with another kind of polarization singularity in their interaction region. The results may be of importance in ultrahigh security of the polarization-encrypted data that utilizes vector vortex beams and multiple optical trapping with non-coaxial superposition of vector vortex beams. We verified our experimental results with theory.

Fractal vector optical fields.

Science.gov (United States)

Pan, Yue; Gao, Xu-Zhen; Cai, Meng-Qiang; Zhang, Guan-Lin; Li, Yongnan; Tu, Chenghou; Wang, Hui-Tian

2016-07-15

We introduce the concept of a fractal, which provides an alternative approach for flexibly engineering the optical fields and their focal fields. We propose, design, and create a new family of optical fields-fractal vector optical fields, which build a bridge between the fractal and vector optical fields. The fractal vector optical fields have polarization states exhibiting fractal geometry, and may also involve the phase and/or amplitude simultaneously. The results reveal that the focal fields exhibit self-similarity, and the hierarchy of the fractal has the "weeding" role. The fractal can be used to engineer the focal field.

Clifford Fourier transform on vector fields.

Science.gov (United States)

Ebling, Julia; Scheuermann, Gerik

2005-01-01

Image processing and computer vision have robust methods for feature extraction and the computation of derivatives of scalar fields. Furthermore, interpolation and the effects of applying a filter can be analyzed in detail and can be advantages when applying these methods to vector fields to obtain a solid theoretical basis for feature extraction. We recently introduced the Clifford convolution, which is an extension of the classical convolution on scalar fields and provides a unified notation for the convolution of scalar and vector fields. It has attractive geometric properties that allow pattern matching on vector fields. In image processing, the convolution and the Fourier transform operators are closely related by the convolution theorem and, in this paper, we extend the Fourier transform to include general elements of Clifford Algebra, called multivectors, including scalars and vectors. The resulting convolution and derivative theorems are extensions of those for convolution and the Fourier transform on scalar fields. The Clifford Fourier transform allows a frequency analysis of vector fields and the behavior of vector-valued filters. In frequency space, vectors are transformed into general multivectors of the Clifford Algebra. Many basic vector-valued patterns, such as source, sink, saddle points, and potential vortices, can be described by a few multivectors in frequency space.

Vector-like quarks: t’ and partners

International Nuclear Information System (INIS)

PANIZZI, L.

2014-01-01

Vector-like quarks are predicted in various scenarios of new physics, and their peculiar signatures from both pair and single production have been already investigated in detail. However no signals of vector-like quarks have been detected so far, pushing limits on their masses above 600–700GeV, depending on assumptions on their couplings. Experimental searches consider specific final states to pose bounds on the mass of a vector-like quark, usually assuming it is the only particle that contributes to the signal of new physics in that specific final state. However, realistic scenarios predict the existence of multiple vector-like quarks, possibly with similar masses. The reinterpretation of mass bounds from experimental searches is therefore not always straightforward. In this analysis I briefly summarise the constraints on vector-like quarks and their possible signatures at the LHC, focusing in particular on a model-independent description of single production processes for vector-like quark that mix with all generations and on the development of a framework to study scenarios with multiple vector-like quarks.

Correlated Topic Vector for Scene Classification.

Science.gov (United States)

Wei, Pengxu; Qin, Fei; Wan, Fang; Zhu, Yi; Jiao, Jianbin; Ye, Qixiang

2017-07-01

Scene images usually involve semantic correlations, particularly when considering large-scale image data sets. This paper proposes a novel generative image representation, correlated topic vector, to model such semantic correlations. Oriented from the correlated topic model, correlated topic vector intends to naturally utilize the correlations among topics, which are seldom considered in the conventional feature encoding, e.g., Fisher vector, but do exist in scene images. It is expected that the involvement of correlations can increase the discriminative capability of the learned generative model and consequently improve the recognition accuracy. Incorporated with the Fisher kernel method, correlated topic vector inherits the advantages of Fisher vector. The contributions to the topics of visual words have been further employed by incorporating the Fisher kernel framework to indicate the differences among scenes. Combined with the deep convolutional neural network (CNN) features and Gibbs sampling solution, correlated topic vector shows great potential when processing large-scale and complex scene image data sets. Experiments on two scene image data sets demonstrate that correlated topic vector improves significantly the deep CNN features, and outperforms existing Fisher kernel-based features.

Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

International Nuclear Information System (INIS)

Gandini, Paolo

2012-01-01

We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f L in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f L ∼ 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B → ρρ and B + → (Omega)ρ + decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f L ∼ 0.5 in B → φK* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.

Test of Understanding of Vectors: A Reliable Multiple-Choice Vector Concept Test

Science.gov (United States)

Barniol, Pablo; Zavala, Genaro

2014-01-01

In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended…

Local Patch Vectors Encoded by Fisher Vectors for Image Classification

Directory of Open Access Journals (Sweden)

Shuangshuang Chen

2018-02-01

Full Text Available The objective of this work is image classification, whose purpose is to group images into corresponding semantic categories. Four contributions are made as follows: (i For computational simplicity and efficiency, we directly adopt raw image patch vectors as local descriptors encoded by Fisher vector (FV subsequently; (ii For obtaining representative local features within the FV encoding framework, we compare and analyze three typical sampling strategies: random sampling, saliency-based sampling and dense sampling; (iii In order to embed both global and local spatial information into local features, we construct an improved spatial geometry structure which shows good performance; (iv For reducing the storage and CPU costs of high dimensional vectors, we adopt a new feature selection method based on supervised mutual information (MI, which chooses features by an importance sorting algorithm. We report experimental results on dataset STL-10. It shows very promising performance with this simple and efficient framework compared to conventional methods.

Vector-Vector Scattering on the Lattice

Science.gov (United States)

Romero-López, Fernando; Urbach, Carsten; Rusetsky, Akaki

2018-03-01

In this work we present an extension of the LüScher formalism to include the interaction of particles with spin, focusing on the scattering of two vector particles. The derived formalism will be applied to Scalar QED in the Higgs Phase, where the U(1) gauge boson acquires mass.

Conformal Killing vectors in Robertson-Walker spacetimes

International Nuclear Information System (INIS)

Maartens, R.; Maharaj, S.d.

1986-01-01

It is well known that Robertson-Walker spacetimes admit a conformal Killingl vector normal to the spacelike homogeneous hypersurfaces. Because these spacetimes are conformally flat, there are a further eight conformal Killing vectors, which are neither normal nor tangent to the homogeneous hypersurfaces. The authors find these further conformal Killing vectors and the Lie algebra of the full G 15 of conformal motions. Conditions on the metric scale factor are determined which reduce some of the conformal Killing vectors to homothetic Killing vectors or Killing vectors, allowing one to regain in a unified way the known special geometries. The non-normal conformal Killing vectors provide a counter-example to show that conformal motions do not, in general, map a fluid flow conformally. These non-normal vectors are also used to find the general solution of the null geodesic equation and photon Liouville equation. (author)

A generalized nonlocal vector calculus

Science.gov (United States)

Alali, Bacim; Liu, Kuo; Gunzburger, Max

2015-10-01

A nonlocal vector calculus was introduced in Du et al. (Math Model Meth Appl Sci 23:493-540, 2013) that has proved useful for the analysis of the peridynamics model of nonlocal mechanics and nonlocal diffusion models. A formulation is developed that provides a more general setting for the nonlocal vector calculus that is independent of particular nonlocal models. It is shown that general nonlocal calculus operators are integral operators with specific integral kernels. General nonlocal calculus properties are developed, including nonlocal integration by parts formula and Green's identities. The nonlocal vector calculus introduced in Du et al. (Math Model Meth Appl Sci 23:493-540, 2013) is shown to be recoverable from the general formulation as a special example. This special nonlocal vector calculus is used to reformulate the peridynamics equation of motion in terms of the nonlocal gradient operator and its adjoint. A new example of nonlocal vector calculus operators is introduced, which shows the potential use of the general formulation for general nonlocal models.

Broad patterns in domestic vector-borne Trypanosoma cruzi transmission dynamics: synanthropic animals and vector control.

Science.gov (United States)

Peterson, Jennifer K; Bartsch, Sarah M; Lee, Bruce Y; Dobson, Andrew P

2015-10-22

Chagas disease (caused by Trypanosoma cruzi) is the most important neglected tropical disease (NTD) in Latin America, infecting an estimated 5.7 million people in the 21 countries where it is endemic. It is one of the NTDs targeted for control and elimination by the 2020 London Declaration goals, with the first goal being to interrupt intra-domiciliary vector-borne T. cruzi transmission. A key question in domestic T. cruzi transmission is the role that synanthropic animals play in T. cruzi transmission to humans. Here, we ask, (1) do synanthropic animals need to be targeted in Chagas disease prevention policies?, and (2) how does the presence of animals affect the efficacy of vector control? We developed a simple mathematical model to simulate domestic vector-borne T. cruzi transmission and to specifically examine the interaction between the presence of synanthropic animals and effects of vector control. We used the model to explore how the interactions between triatomine bugs, humans and animals impact the number and proportion of T. cruzi-infected bugs and humans. We then examined how T. cruzi dynamics change when control measures targeting vector abundance are introduced into the system. We found that the presence of synanthropic animals slows the speed of T. cruzi transmission to humans, and increases the sensitivity of T. cruzi transmission dynamics to vector control measures at comparable triatomine carrying capacities. However, T. cruzi transmission is amplified when triatomine carrying capacity increases with the abundance of syntathoropic hosts. Our results suggest that in domestic T. cruzi transmission scenarios where no vector control measures are in place, a reduction in synanthropic animals may slow T. cruzi transmission to humans, but it would not completely eliminate transmission. To reach the 2020 goal of interrupting intra-domiciliary T. cruzi transmission, it is critical to target vector populations. Additionally, where vector control measures

Spin information from vector-meson decay in photoproduction

International Nuclear Information System (INIS)

Kloet, W.M.; Chiang, W.; Tabakin, F.

1998-01-01

For the photoproduction of vector mesons, all single and double spin observables involving vector-meson two-body decays are defined consistently in the γN center-of-mass frame. These definitions yield a procedure for extracting physically meaningful single and double spin observables that are subject to known rules concerning their angle and energy evolution. As part of this analysis, we show that measuring the two-meson decay of a photo produced ρ or φ does not determine the vector meson's vector polarization, but only its tensor polarization. The vector meson decay into lepton pairs is also insensitive to the vector meson's vector polarization, unless one measures the spin of one of the leptons. Similar results are found for all double spin observables which involve observation of vector-meson decay. To access the vector meson's vector polarization, one therefore needs to either measure the spin of the decay leptons, make an analysis of the background interference effects, or relate the vector meson's vector polarization to other accessible spin observables. copyright 1998 The American Physical Society

[Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

Science.gov (United States)

He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

2014-05-01

Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

Virus-Vectored Influenza Virus Vaccines

Science.gov (United States)

Tripp, Ralph A.; Tompkins, S. Mark

2014-01-01

Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

Vector Boson Scattering at High Mass

CERN Document Server

The ATLAS collaboration

2009-01-01

In the absence of a light Higgs boson, the mechanism of electroweak symmetry breaking will be best studied in processes of vector boson scattering at high mass. Various models predict resonances in this channel. Here, we investigate $WW $scalar and vector resonances, $WZ$ vector resonances and a $ZZ$ scalar resonance over a range of diboson centre-of-mass energies. Particular attention is paid to the application of forward jet tagging and to the reconstruction of dijet pairs with low opening angle resulting from the decay of highly boosted vector bosons. The performances of different jet algorithms are compared. We find that resonances in vector boson scattering can be discovered with a few tens of inverse femtobarns of integrated luminosity.

Symmetric vectors and algebraic classification

International Nuclear Information System (INIS)

Leibowitz, E.

1980-01-01

The concept of symmetric vector field in Riemannian manifolds, which arises in the study of relativistic cosmological models, is analyzed. Symmetric vectors are tied up with the algebraic properties of the manifold curvature. A procedure for generating a congruence of symmetric fields out of a given pair is outlined. The case of a three-dimensional manifold of constant curvature (''isotropic universe'') is studied in detail, with all its symmetric vector fields being explicitly constructed

[New strategy for RNA vectorization in mammalian cells. Use of a peptide vector].

Science.gov (United States)

Vidal, P; Morris, M C; Chaloin, L; Heitz, F; Divita, G

1997-04-01

A major barrier for gene delivery is the low permeability of nucleic acids to cellular membranes. The development of antisenses and gene therapy has focused mainly on improving methods of oligonucleotide or gene delivery to the cell. In this report we described a new strategy for RNA cell delivery, based on a short single peptide. This peptide vector is derived from both the fusion domain of the gp41 protein of HIV and the nuclear localization sequence of the SV40 large T antigen. This peptide vector localizes rapidly to the cytoplasm then to the nucleus of human fibroblasts (HS-68) within a few minutes and exhibits a high affinity for a single-stranded mRNA encoding the p66 subunit of the HIV-1 reverse transcriptase (in a 100 nM range). The peptide/RNA complex formation involves mainly electrostatic interactions between the basic residues of the peptide and the charges on the phosphate group of the RNA. In the presence of the peptide-vector fluorescently-labelled mRNA is delivered into the cytoplasm of mammalian cells (HS68 human fibroblasts) in less than 1 h with a relatively high efficiency (80%). This new concept based on a peptide-derived vector offers several advantages compared to other compounds commonly used in gene delivery. This vector is highly soluble and exhibits no cytotoxicity at the concentrations used for optimal gene delivery. This result clearly supports the fact that this peptide vector is a powerful tool and that it can be used widely, as much for laboratory research as for new applications and development in gene and/or antisense therapy.

Attenuated Vector Tomography -- An Approach to Image Flow Vector Fields with Doppler Ultrasonic Imaging

International Nuclear Information System (INIS)

Huang, Qiu; Peng, Qiyu; Huang, Bin; Cheryauka, Arvi; Gullberg, Grant T.

2008-01-01

The measurement of flow obtained using continuous wave Doppler ultrasound is formulated as a directional projection of a flow vector field. When a continuous ultrasound wave bounces against a flowing particle, a signal is backscattered. This signal obtains a Doppler frequency shift proportional to the speed of the particle along the ultrasound beam. This occurs for each particle along the beam, giving rise to a Doppler velocity spectrum. The first moment of the spectrum provides the directional projection of the flow along the ultrasound beam. Signals reflected from points further away from the detector will have lower amplitude than signals reflected from points closer to the detector. The effect is very much akin to that modeled by the attenuated Radon transform in emission computed tomography.A least-squares method was adopted to reconstruct a 2D vector field from directional projection measurements. Attenuated projections of only the longitudinal projections of the vector field were simulated. The components of the vector field were reconstructed using the gradient algorithm to minimize a least-squares criterion. This result was compared with the reconstruction of longitudinal projections of the vector field without attenuation. If attenuation is known, the algorithm was able to accurately reconstruct both components of the full vector field from only one set of directional projection measurements. A better reconstruction was obtained with attenuation than without attenuation implying that attenuation provides important information for the reconstruction of flow vector fields.This confirms previous work where we showed that knowledge of the attenuation distribution helps in the reconstruction of MRI diffusion tensor fields from fewer than the required measurements. In the application of ultrasound the attenuation distribution is obtained with pulse wave transmission computed tomography and flow information is obtained with continuous wave Doppler

40 CFR 503.33 - Vector attraction reduction.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Vector attraction reduction. 503.33... STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE Pathogens and Vector Attraction Reduction § 503.33 Vector attraction reduction. (a)(1) One of the vector attraction reduction requirements in § 503.33 (b)(1) through...

Vector Boson Scattering at High Mass

CERN Document Server

Sherwood, P

2009-01-01

In the absence of a light Higgs boson, the mechanism of electroweak symmetry breaking will be best studied in processes of vector boson scattering at high mass. Various models predict resonances in this channel. Here, we investigate W W scalar and vector resonances, W Z vector resonances and a Z Z scalar resonance over a range of diboson centre-of-mass energies. Particular attention is paid to the application reconstruction of dijet pairs with low opening angle resulting from the decay of highly boosted vector bosons.

Optimality Conditions in Vector Optimization

CERN Document Server

Jiménez, Manuel Arana; Lizana, Antonio Rufián

2011-01-01

Vector optimization is continuously needed in several science fields, particularly in economy, business, engineering, physics and mathematics. The evolution of these fields depends, in part, on the improvements in vector optimization in mathematical programming. The aim of this Ebook is to present the latest developments in vector optimization. The contributions have been written by some of the most eminent researchers in this field of mathematical programming. The Ebook is considered essential for researchers and students in this field.

Multineuronal vectorization is more efficient than time-segmental vectorization for information extraction from neuronal activities in the inferior temporal cortex.

Science.gov (United States)

Kaneko, Hidekazu; Tamura, Hiroshi; Tate, Shunta; Kawashima, Takahiro; Suzuki, Shinya S; Fujita, Ichiro

2010-08-01

In order for patients with disabilities to control assistive devices with their own neural activity, multineuronal spike trains must be efficiently decoded because only limited computational resources can be used to generate prosthetic control signals in portable real-time applications. In this study, we compare the abilities of two vectorizing procedures (multineuronal and time-segmental) to extract information from spike trains during the same total neuron-seconds. In the multineuronal vectorizing procedure, we defined a response vector whose components represented the spike counts of one to five neurons. In the time-segmental vectorizing procedure, a response vector consisted of components representing a neuron's spike counts for one to five time-segment(s) of a response period of 1 s. Spike trains were recorded from neurons in the inferior temporal cortex of monkeys presented with visual stimuli. We examined whether the amount of information of the visual stimuli carried by these neurons differed between the two vectorizing procedures. The amount of information calculated with the multineuronal vectorizing procedure, but not the time-segmental vectorizing procedure, significantly increased with the dimensions of the response vector. We conclude that the multineuronal vectorizing procedure is superior to the time-segmental vectorizing procedure in efficiently extracting information from neuronal signals. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Adenoviral vector immunity: its implications and circumvention strategies.

Science.gov (United States)

Ahi, Yadvinder S; Bangari, Dinesh S; Mittal, Suresh K

2011-08-01

Adenoviral (Ad) vectors have emerged as a promising gene delivery platform for a variety of therapeutic and vaccine purposes during last two decades. However, the presence of preexisting Ad immunity and the rapid development of Ad vector immunity still pose significant challenges to the clinical use of these vectors. Innate inflammatory response following Ad vector administration may lead to systemic toxicity, drastically limit vector transduction efficiency and significantly abbreviate the duration of transgene expression. Currently, a number of approaches are being extensively pursued to overcome these drawbacks by strategies that target either the host or the Ad vector. In addition, significant progress has been made in the development of novel Ad vectors based on less prevalent human Ad serotypes and nonhuman Ad. This review provides an update on our current understanding of immune responses to Ad vectors and delineates various approaches for eluding Ad vector immunity. Approaches targeting the host and those targeting the vector are discussed in light of their promises and limitations.

A Subdivision-Based Representation for Vector Image Editing.

Science.gov (United States)

Liao, Zicheng; Hoppe, Hugues; Forsyth, David; Yu, Yizhou

2012-11-01

Vector graphics has been employed in a wide variety of applications due to its scalability and editability. Editability is a high priority for artists and designers who wish to produce vector-based graphical content with user interaction. In this paper, we introduce a new vector image representation based on piecewise smooth subdivision surfaces, which is a simple, unified and flexible framework that supports a variety of operations, including shape editing, color editing, image stylization, and vector image processing. These operations effectively create novel vector graphics by reusing and altering existing image vectorization results. Because image vectorization yields an abstraction of the original raster image, controlling the level of detail of this abstraction is highly desirable. To this end, we design a feature-oriented vector image pyramid that offers multiple levels of abstraction simultaneously. Our new vector image representation can be rasterized efficiently using GPU-accelerated subdivision. Experiments indicate that our vector image representation achieves high visual quality and better supports editing operations than existing representations.

Ocorrência de Achatina fulica no Vale do Paraíba, Estado do Rio de Janeiro, Brasil Occurrence of Achatina fulica in the Vale do Paraíba, Rio de Janeiro state, Brazil

Directory of Open Access Journals (Sweden)

Maurício Carvalho de Vasconcellos

2001-12-01

Full Text Available Registrou-se no município de Resende, Estado do Rio de Janeiro, Brasil, a primeira ocorrência do molusco Achatina fulica hospedeiro intermediário de Angiostrongylus cantonensis, causador da angiostrongilíase meningoencefálica. Em cinco bairros visitados, foram encontrados moluscos vivendo livremente, e nenhum dos animais coletados apresentava a forma larvar do parasito. A presença de A. fulica pode estar relacionada à comercialização desse molusco como alimento, e representa possibilidade de instalação dessa zoonose na região.The first occurrence of the Achatina fulica, an intermediate host of Angiostrongylus cantonensis, the etiological agent of meningoencephalic angiostrongiliasis, is reported in Resende municipality, Brazil. In the five visited localities, snails were found living freely, and the larvae of this parasite was not seen in any of them. The finding of A. fulica in the area may be related to its commercialization as a food item and embodies the possibility of new focus.

Generalized Selection Weighted Vector Filters

Directory of Open Access Journals (Sweden)

Rastislav Lukac

2004-09-01

Full Text Available This paper introduces a class of nonlinear multichannel filters capable of removing impulsive noise in color images. The here-proposed generalized selection weighted vector filter class constitutes a powerful filtering framework for multichannel signal processing. Previously defined multichannel filters such as vector median filter, basic vector directional filter, directional-distance filter, weighted vector median filters, and weighted vector directional filters are treated from a global viewpoint using the proposed framework. Robust order-statistic concepts and increased degree of freedom in filter design make the proposed method attractive for a variety of applications. Introduced multichannel sigmoidal adaptation of the filter parameters and its modifications allow to accommodate the filter parameters to varying signal and noise statistics. Simulation studies reported in this paper indicate that the proposed filter class is computationally attractive, yields excellent performance, and is able to preserve fine details and color information while efficiently suppressing impulsive noise. This paper is an extended version of the paper by Lukac et al. presented at the 2003 IEEE-EURASIP Workshop on Nonlinear Signal and Image Processing (NSIP '03 in Grado, Italy.

Production of lentiviral vectors

Directory of Open Access Journals (Sweden)

Otto-Wilhelm Merten

2016-01-01

Full Text Available Lentiviral vectors (LV have seen considerably increase in use as gene therapy vectors for the treatment of acquired and inherited diseases. This review presents the state of the art of the production of these vectors with particular emphasis on their large-scale production for clinical purposes. In contrast to oncoretroviral vectors, which are produced using stable producer cell lines, clinical-grade LV are in most of the cases produced by transient transfection of 293 or 293T cells grown in cell factories. However, more recent developments, also, tend to use hollow fiber reactor, suspension culture processes, and the implementation of stable producer cell lines. As is customary for the biotech industry, rather sophisticated downstream processing protocols have been established to remove any undesirable process-derived contaminant, such as plasmid or host cell DNA or host cell proteins. This review compares published large-scale production and purification processes of LV and presents their process performances. Furthermore, developments in the domain of stable cell lines and their way to the use of production vehicles of clinical material will be presented.

Inverse Operation of Four-dimensional Vector Matrix

OpenAIRE

H J Bao; A J Sang; H X Chen

2011-01-01

This is a new series of study to define and prove multidimensional vector matrix mathematics, which includes four-dimensional vector matrix determinant, four-dimensional vector matrix inverse and related properties. There are innovative concepts of multi-dimensional vector matrix mathematics created by authors with numerous applications in engineering, math, video conferencing, 3D TV, and other fields.

Multiscale vector fields for image pattern recognition

Science.gov (United States)

Low, Kah-Chan; Coggins, James M.

1990-01-01

A uniform processing framework for low-level vision computing in which a bank of spatial filters maps the image intensity structure at each pixel into an abstract feature space is proposed. Some properties of the filters and the feature space are described. Local orientation is measured by a vector sum in the feature space as follows: each filter's preferred orientation along with the strength of the filter's output determine the orientation and the length of a vector in the feature space; the vectors for all filters are summed to yield a resultant vector for a particular pixel and scale. The orientation of the resultant vector indicates the local orientation, and the magnitude of the vector indicates the strength of the local orientation preference. Limitations of the vector sum method are discussed. Investigations show that the processing framework provides a useful, redundant representation of image structure across orientation and scale.

Vector control of induction machines

CERN Document Server

Robyns, Benoit

2012-01-01

After a brief introduction to the main law of physics and fundamental concepts inherent in electromechanical conversion, ""Vector Control of Induction Machines"" introduces the standard mathematical models for induction machines - whichever rotor technology is used - as well as several squirrel-cage induction machine vector-control strategies. The use of causal ordering graphs allows systematization of the design stage, as well as standardization of the structure of control devices. ""Vector Control of Induction Machines"" suggests a unique approach aimed at reducing parameter sensitivity for

Viral vector-based influenza vaccines

Science.gov (United States)

de Vries, Rory D.; Rimmelzwaan, Guus F.

2016-01-01

ABSTRACT Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors. PMID:27455345

Integrated optic vector-matrix multiplier

Science.gov (United States)

Watts, Michael R [Albuquerque, NM

2011-09-27

A vector-matrix multiplier is disclosed which uses N different wavelengths of light that are modulated with amplitudes representing elements of an N.times.1 vector and combined to form an input wavelength-division multiplexed (WDM) light stream. The input WDM light stream is split into N streamlets from which each wavelength of the light is individually coupled out and modulated for a second time using an input signal representing elements of an M.times.N matrix, and is then coupled into an output waveguide for each streamlet to form an output WDM light stream which is detected to generate a product of the vector and matrix. The vector-matrix multiplier can be formed as an integrated optical circuit using either waveguide amplitude modulators or ring resonator amplitude modulators.

3D vector flow imaging

DEFF Research Database (Denmark)

Pihl, Michael Johannes

The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... are (vx, vy, vz) = (-0.03, 95, 1.0) ± (9, 6, 1) cm/s compared with the expected (0, 96, 0) cm/s. Afterwards, 3D vector flow images from a cross-sectional plane of the vessel are presented. The out of plane velocities exhibit the expected 2D circular-symmetric parabolic shape. The experimental results...... verify that the 3D TO method estimates the complete 3D velocity vectors, and that the method is suitable for 3D vector flow imaging....

Problems and worked solutions in vector analysis

CERN Document Server

Shorter, LR

2014-01-01

""A handy book like this,"" noted The Mathematical Gazette, ""will fill a great want."" Devoted to fully worked out examples, this unique text constitutes a self-contained introductory course in vector analysis for undergraduate and graduate students of applied mathematics.Opening chapters define vector addition and subtraction, show how to resolve and determine the direction of two or more vectors, and explain systems of coordinates, vector equations of a plane and straight line, relative velocity and acceleration, and infinitely small vectors. The following chapters deal with scalar and vect

An adeno-associated viral vector transduces the rat hypothalamus and amygdala more efficient than a lentiviral vector

Directory of Open Access Journals (Sweden)

Vreugdenhil Erno

2010-07-01

Full Text Available Abstract Background This study compared the transduction efficiencies of an adeno-associated viral (AAV vector, which was pseudotyped with an AAV1 capsid and encoded the green fluorescent protein (GFP, with a lentiviral (LV vector, which was pseudotyped with a VSV-G envelop and encoded the discosoma red fluorescent protein (dsRed, to investigate which viral vector transduced the lateral hypothalamus or the amygdala more efficiently. The LV-dsRed and AAV1-GFP vector were mixed and injected into the lateral hypothalamus or into the amygdala of adult rats. The titers that were injected were 1 × 108 or 1 × 109 genomic copies of AAV1-GFP and 1 × 105 transducing units of LV-dsRed. Results Immunostaining for GFP and dsRed showed that AAV1-GFP transduced significantly more cells than LV-dsRed in both the lateral hypothalamus and the amygdala. In addition, the number of LV particles that were injected can not easily be increased, while the number of AAV1 particles can be increased easily with a factor 100 to 1000. Both viral vectors appear to predominantly transduce neurons. Conclusions This study showed that AAV1 vectors are better tools to overexpress or knockdown genes in the lateral hypothalamus and amygdala of adult rats, since more cells can be transduced with AAV1 than with LV vectors and the titer of AAV1 vectors can easily be increased to transduce the area of interest.

Gauge structure of neutral-vector field theory. [Massive vector fields, massless limits

Energy Technology Data Exchange (ETDEWEB)

Kubo, R; Yokoyama, [Hiroshima univ., Takehara (Japan). Research Inst. for Theoretical Physics

1975-03-01

General aspects of gauge structure of neutral-vector field theory are investigated from an extended standpoint, where massive vector fields are treated in a form corresponding to the electromagnetic fields in a general gauge formalism reported previously. All results obtained are shown to have unique massless limits. It is shown that a generalized q-number gauge transformation for fields makes the theory invariant in cooperation with a simultaneous transformation for relevant gauge parameters. A method of differentiation with respect to a gauge variable is found to clarify some essential features of the gauge structure. Two possible types of gauge structure also emerge correspondingly to the massless case. A neutral-vector field theory proposed in a preceding paper is included in the present framework as the most preferable case.

Matrix vector analysis

CERN Document Server

Eisenman, Richard L

2005-01-01

This outstanding text and reference applies matrix ideas to vector methods, using physical ideas to illustrate and motivate mathematical concepts but employing a mathematical continuity of development rather than a physical approach. The author, who taught at the U.S. Air Force Academy, dispenses with the artificial barrier between vectors and matrices--and more generally, between pure and applied mathematics.Motivated examples introduce each idea, with interpretations of physical, algebraic, and geometric contexts, in addition to generalizations to theorems that reflect the essential structur

Declining Prevalence of Disease Vectors Under Climate Change

Science.gov (United States)

Escobar, Luis E.; Romero-Alvarez, Daniel; Leon, Renato; Lepe-Lopez, Manuel A.; Craft, Meggan E.; Borbor-Cordova, Mercy J.; Svenning, Jens-Christian

2016-12-01

More than half of the world population is at risk of vector-borne diseases including dengue fever, chikungunya, zika, yellow fever, leishmaniasis, chagas disease, and malaria, with highest incidences in tropical regions. In Ecuador, vector-borne diseases are present from coastal and Amazonian regions to the Andes Mountains; however, a detailed characterization of the distribution of their vectors has never been carried out. We estimate the distribution of 14 vectors of the above vector-borne diseases under present-day and future climates. Our results consistently suggest that climate warming is likely threatening some vector species with extinction, locally or completely. These results suggest that climate change could reduce the burden of specific vector species. Other vector species are likely to shift and constrain their geographic range to the highlands in Ecuador potentially affecting novel areas and populations. These forecasts show the need for development of early prevention strategies for vector species currently absent in areas projected as suitable under future climate conditions. Informed interventions could reduce the risk of human exposure to vector species with distributional shifts, in response to current and future climate changes. Based on the mixed effects of future climate on human exposure to disease vectors, we argue that research on vector-borne diseases should be cross-scale and include climatic, demographic, and landscape factors, as well as forces facilitating disease transmission at fine scales.

Vector boson scattering at CLIC

Energy Technology Data Exchange (ETDEWEB)

Kilian, Wolfgang; Fleper, Christian [Department Physik, Universitaet Siegen, 57068 Siegen (Germany); Reuter, Juergen [DESY Theory Group, 22603 Hamburg (Germany); Sekulla, Marco [Institut fuer Theoretische Physik, Karlsruher Institut fuer Technologie, 76131 Karlsruhe (Germany)

2016-07-01

Linear colliders operating in a range of multiple TeV are able to investigate the details of vector boson scattering and electroweak symmetry breaking. We calculate cross sections with the Monte Carlo generator WHIZARD for vector boson scattering processes at the future linear e{sup +} e{sup -} collider CLIC. By finding suitable cuts, the vector boson scattering signal processes are isolated from the background. Finally, we are able to determine exclusion sensitivities on the non-Standard Model parameters of the relevant dimension eight operators.

Decays of the vector glueball

Science.gov (United States)

Giacosa, Francesco; Sammet, Julia; Janowski, Stanislaus

2017-06-01

We calculate two- and three-body decays of the (lightest) vector glueball into (pseudo)scalar, (axial-)vector, as well as pseudovector and excited vector mesons in the framework of a model of QCD. While absolute values of widths cannot be predicted because the corresponding coupling constants are unknown, some interesting branching ratios can be evaluated by setting the mass of the yet hypothetical vector glueball to 3.8 GeV as predicted by quenched lattice QCD. We find that the decay mode ω π π should be one of the largest (both through the decay chain O →b1π →ω π π and through the direct coupling O →ω π π ). Similarly, the (direct and indirect) decay into π K K*(892 ) is sizable. Moreover, the decays into ρ π and K*(892 )K are, although subleading, possible and could play a role in explaining the ρ π puzzle of the charmonium state ψ (2 S ) thanks to a (small) mixing with the vector glueball. The vector glueball can be directly formed at the ongoing BESIII experiment as well as at the future PANDA experiment at the FAIR facility. If the width is sufficiently small (≲100 MeV ) it should not escape future detection. It should be stressed that the employed model is based on some inputs and simplifying assumptions: the value of glueball mass (at present, the quenched lattice value is used), the lack of mixing of the glueball with other quarkonium states, and the use of few interaction terms. It then represents a first step toward the identification of the main decay channels of the vector glueball, but shall be improved when corresponding experimental candidates and/or new lattice results will be available.

Virtual-vector-based space vector pulse width modulation of the DC-AC multilevel-clamped multilevel converter (MLC²)

DEFF Research Database (Denmark)

Rodriguez, Pedro; Busquets-Monge, Sergio; Blaabjerg, Frede

2011-01-01

This work presents the development of the space vector pulse width modulation (SVPWM) of a new multi-level converter topology. First, the proposed converter and its natural space vector diagram are presented. Secondly, a modified space vector diagram based on the virtual-vectors technique is show...

Image Coding Based on Address Vector Quantization.

Science.gov (United States)

Feng, Yushu

Image coding is finding increased application in teleconferencing, archiving, and remote sensing. This thesis investigates the potential of Vector Quantization (VQ), a relatively new source coding technique, for compression of monochromatic and color images. Extensions of the Vector Quantization technique to the Address Vector Quantization method have been investigated. In Vector Quantization, the image data to be encoded are first processed to yield a set of vectors. A codeword from the codebook which best matches the input image vector is then selected. Compression is achieved by replacing the image vector with the index of the code-word which produced the best match, the index is sent to the channel. Reconstruction of the image is done by using a table lookup technique, where the label is simply used as an address for a table containing the representative vectors. A code-book of representative vectors (codewords) is generated using an iterative clustering algorithm such as K-means, or the generalized Lloyd algorithm. A review of different Vector Quantization techniques are given in chapter 1. Chapter 2 gives an overview of codebook design methods including the Kohonen neural network to design codebook. During the encoding process, the correlation of the address is considered and Address Vector Quantization is developed for color image and monochrome image coding. Address VQ which includes static and dynamic processes is introduced in chapter 3. In order to overcome the problems in Hierarchical VQ, Multi-layer Address Vector Quantization is proposed in chapter 4. This approach gives the same performance as that of the normal VQ scheme but the bit rate is about 1/2 to 1/3 as that of the normal VQ method. In chapter 5, a Dynamic Finite State VQ based on a probability transition matrix to select the best subcodebook to encode the image is developed. In chapter 6, a new adaptive vector quantization scheme, suitable for color video coding, called "A Self -Organizing

Transcriptional Silencing of Retroviral Vectors

DEFF Research Database (Denmark)

Lund, Anders Henrik; Duch, M.; Pedersen, F.S.

1996-01-01

. Extinction of long-term vector expression has been observed after implantation of transduced hematopoietic cells as well as fibroblasts, myoblasts and hepatocytes. Here we review the influence of vector structure, integration site and cell type on transcriptional silencing. While down-regulation of proviral...... transcription is known from a number of cellular and animal models, major insight has been gained from studies in the germ line and embryonal cells of the mouse. Key elements for the transfer and expression of retroviral vectors, such as the viral transcriptional enhancer and the binding site for the t......RNA primer for reverse transcription may have a major influence on transcriptional silencing. Alterations of these elements of the vector backbone as well as the use of internal promoter elements from housekeeping genes may contribute to reduce transcriptional silencing. The use of cell culture and animal...

Estimation of pure autoregressive vector models for revenue series ...

African Journals Online (AJOL)

This paper aims at applying multivariate approach to Box and Jenkins univariate time series modeling to three vector series. General Autoregressive Vector Models with time varying coefficients are estimated. The first vector is a response vector, while others are predictor vectors. By matrix expansion each vector, whether ...

On the Witt vector Frobenius

DEFF Research Database (Denmark)

Davis, Christopher James; Kedlaya, Kiran

2014-01-01

We study the kernel and cokernel of the Frobenius map on the p-typical Witt vectors of a commutative ring, not necessarily of characteristic p. We give many equivalent conditions to surjectivity of the Frobenius map on both finite and infinite length Witt vectors. In particular, surjectivity...... on finite Witt vectors turns out to be stable under certain integral extensions; this provides a clean formulation of a strong generalization of Faltings’s almost purity theorem from p-adic Hodge theory, incorporating recent improvements by Kedlaya–Liu and by Scholze....

Design and Potential of Non-Integrating Lentiviral Vectors

Directory of Open Access Journals (Sweden)

Aaron Shaw

2014-01-01

Full Text Available Lentiviral vectors have demonstrated promising results in clinical trials that target cells of the hematopoietic system. For these applications, they are the vectors of choice since they provide stable integration into cells that will undergo extensive expansion in vivo. Unfortunately, integration can have unintended consequences including dysregulated cell growth. Therefore, lentiviral vectors that do not integrate are predicted to have a safer profile compared to integrating vectors and should be considered for applications where transient expression is required or for sustained episomal expression such as in quiescent cells. In this review, the system for generating lentiviral vectors will be described and used to illustrate how alterations in the viral integrase or vector Long Terminal Repeats have been used to generate vectors that lack the ability to integrate. In addition to their safety advantages, these non-integrating lentiviral vectors can be used when persistent expression would have adverse consequences. Vectors are currently in development for use in vaccinations, cancer therapy, site-directed gene insertions, gene disruption strategies, and cell reprogramming. Preclinical work will be described that illustrates the potential of this unique vector system in human gene therapy.

Helminth parasites of the Mediterranean gecko, Hemidactylus turcicus (Sauria: Gekkonidae), from Texas, United States with a summary of helminths of this host.

Science.gov (United States)

McAllister, Chris T; Bursey, Charles R

2016-09-01

One hundred-thirty six Mediterranean geckos, Hemidactylus turcicus, were collected between December 1986 and March 2016 in Hardin (n = 7), Harris (n = 57), and Tom Green (n = 72) counties, Texas, USA., and examined for helminth parasites. Fifty-two H. turcicus (38%) were infected with at least one helminth species. Found were a trematode, Mesocoelium meggitti, three cestodes, Mesocestoides sp. (tetrathyridia), Oochoristica ameivae and Oochoristica scelopori, and four nematodes, Cosmocercoides variabilis, Oswaldocruzia pipiens, Parapharyngodon cubensis, and larvae of Physaloptera sp. Oochoristica ameivae, O. scelopori, P. cubensis, Physaloptera sp., and Os. pipiens represent new host records for H. turcicus and M. meggitti is reported from Texas for the first time. A summary of the helminth parasites of both native and non-native H. turcicus is presented.

Archimedeanization of ordered vector spaces

OpenAIRE

Emelyanov, Eduard Yu.

2014-01-01

In the case of an ordered vector space with an order unit, the Archimedeanization method has been developed recently by V.I Paulsen and M. Tomforde. We present a general version of the Archimedeanization which covers arbitrary ordered vector spaces.

Conhecimento popular: impactos e métodos de controle de Achatina fulica em Valença – RJ, Brasil

Directory of Open Access Journals (Sweden)

Evelyn Chicarino Durço

2012-12-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2013v26n1p189 O objetivo deste estudo foi verificar a incidência do caramujo africano Achatina fulica no bairro Cambota, Valença-RJ, Brasil, e investigar as estratégias de controle adotadas pela população. Questionários epidemiológicos aplicados a 105 moradores averiguaram a existência de contato deles com o animal, o risco de contágio por parasitos, por conta dos hábitos de higiene, e os métodos de controle adotados. A presença dos moluscos foi relatada em 52,5% das residências visitadas. Dessas, 51,4% apresentaram roedores. Moluscos coletados foram analisados quanto à presença de nematoides. Nas residências positivas para a presença de A. fulica foi relatado contato direto com os moluscos (21,9% por manuseio (muitas vezes inadequado ou por ingestão. Todos os entrevistados disseram utilizar alguma técnica para higienização dos alimentos e 67,6% relataram conhecer a angiostrongilíase. Todos os entrevistados disseram praticar o extermínio dos moluscos, 28,5% desses efetuando a quebra da concha. Apesar da alta incidência de A. fulica, não foram encontradas larvas de Angiostrongylus sp. ou de outros nematoides de importância médico-veterinária nos espécimes analisados.

How random is a random vector?

International Nuclear Information System (INIS)

Eliazar, Iddo

2015-01-01

Over 80 years ago Samuel Wilks proposed that the “generalized variance” of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the “Wilks standard deviation” –the square root of the generalized variance–is indeed the standard deviation of a random vector. We further establish that the “uncorrelation index” –a derivative of the Wilks standard deviation–is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: “randomness measures” and “independence indices” of random vectors. In turn, these general notions give rise to “randomness diagrams”—tangible planar visualizations that answer the question: How random is a random vector? The notion of “independence indices” yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

How random is a random vector?

Science.gov (United States)

Eliazar, Iddo

2015-12-01

Over 80 years ago Samuel Wilks proposed that the "generalized variance" of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the "Wilks standard deviation" -the square root of the generalized variance-is indeed the standard deviation of a random vector. We further establish that the "uncorrelation index" -a derivative of the Wilks standard deviation-is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: "randomness measures" and "independence indices" of random vectors. In turn, these general notions give rise to "randomness diagrams"-tangible planar visualizations that answer the question: How random is a random vector? The notion of "independence indices" yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

Projection correlation between two random vectors.

Science.gov (United States)

Zhu, Liping; Xu, Kai; Li, Runze; Zhong, Wei

2017-12-01

We propose the use of projection correlation to characterize dependence between two random vectors. Projection correlation has several appealing properties. It equals zero if and only if the two random vectors are independent, it is not sensitive to the dimensions of the two random vectors, it is invariant with respect to the group of orthogonal transformations, and its estimation is free of tuning parameters and does not require moment conditions on the random vectors. We show that the sample estimate of the projection correction is [Formula: see text]-consistent if the two random vectors are independent and root-[Formula: see text]-consistent otherwise. Monte Carlo simulation studies indicate that the projection correlation has higher power than the distance correlation and the ranks of distances in tests of independence, especially when the dimensions are relatively large or the moment conditions required by the distance correlation are violated.

Simplified Representation of Vector Fields

NARCIS (Netherlands)

Telea, Alexandru; Wijk, Jarke J. van

1999-01-01

Vector field visualization remains a difficult task. Although many local and global visualization methods for vector fields such as flow data exist, they usually require extensive user experience on setting the visualization parameters in order to produce images communicating the desired insight. We

Problems of vector Lagrangians in field theories

International Nuclear Information System (INIS)

Krivsky, I.Yu.; Simulik, V.M.

1997-01-01

A vector Lagrange approach to the Dirac spinor field and the relationship between the vector Lagrangians for the spinor and electromagnetic fields are considered. A vector Lagrange approach for the system of interacting electromagnetic B=(B μ υ)=(E-bar,H-bar) and spinor Ψ fields is constructed. New Lagrangians (scalar and vector) for electromagnetic field in terms of field strengths are found. The foundations of two new QED models are formulated

Produção sustentável e controlada de ostras

OpenAIRE

Jacomel, Bruno

2014-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-graduação em Engenharia de Produção, Florianópolis, 2014 Santa Catarina posiciona-se atualmente como o segundo maior polo produtor de moluscos bivalves da América Latina. Além disso, o estado é responsável por 95% da produção nacional de moluscos bivalves. Dada a crescente importância conquistada pelo setor, este trabalho tem o objetivo de realizar uma analise comparativa entre os resultado...

Effective SIMD Vectorization for Intel Xeon Phi Coprocessors

OpenAIRE

Tian, Xinmin; Saito, Hideki; Preis, Serguei V.; Garcia, Eric N.; Kozhukhov, Sergey S.; Masten, Matt; Cherkasov, Aleksei G.; Panchenko, Nikolay

2015-01-01

Efficiently exploiting SIMD vector units is one of the most important aspects in achieving high performance of the application code running on Intel Xeon Phi coprocessors. In this paper, we present several effective SIMD vectorization techniques such as less-than-full-vector loop vectorization, Intel MIC specific alignment optimization, and small matrix transpose/multiplication 2D vectorization implemented in the Intel C/C++ and Fortran production compilers for Intel Xeon Phi coprocessors. A ...

Vectors of rickettsiae in Africa.

Science.gov (United States)

Bitam, Idir

2012-12-01

Vector-borne diseases are caused by parasites, bacteria, or viruses transmitted by the bites of hematophagous arthropods. In Africa, there has been a recent emergence of new diseases and the re-emergence of existing diseases, usually with changes in disease epidemiology (e.g., geographical distribution, prevalence, and pathogenicity). In Africa, rickettsioses are recognized as important emerging vector-borne infections in humans. Rickettsial diseases are transmitted by different types of arthropods, ticks, fleas, lice, and mites. This review will examine the roles of these different arthropod vectors and their geographical distributions. Copyright © 2012 Elsevier GmbH. All rights reserved.

Modeling vector nonlinear time series using POLYMARS

NARCIS (Netherlands)

de Gooijer, J.G.; Ray, B.K.

2003-01-01

A modified multivariate adaptive regression splines method for modeling vector nonlinear time series is investigated. The method results in models that can capture certain types of vector self-exciting threshold autoregressive behavior, as well as provide good predictions for more general vector

Support vector machines applications

CERN Document Server

Guo, Guodong

2014-01-01

Support vector machines (SVM) have both a solid mathematical background and good performance in practical applications. This book focuses on the recent advances and applications of the SVM in different areas, such as image processing, medical practice, computer vision, pattern recognition, machine learning, applied statistics, business intelligence, and artificial intelligence. The aim of this book is to create a comprehensive source on support vector machine applications, especially some recent advances.

Effective SIMD Vectorization for Intel Xeon Phi Coprocessors

Directory of Open Access Journals (Sweden)

Xinmin Tian

2015-01-01

Full Text Available Efficiently exploiting SIMD vector units is one of the most important aspects in achieving high performance of the application code running on Intel Xeon Phi coprocessors. In this paper, we present several effective SIMD vectorization techniques such as less-than-full-vector loop vectorization, Intel MIC specific alignment optimization, and small matrix transpose/multiplication 2D vectorization implemented in the Intel C/C++ and Fortran production compilers for Intel Xeon Phi coprocessors. A set of workloads from several application domains is employed to conduct the performance study of our SIMD vectorization techniques. The performance results show that we achieved up to 12.5x performance gain on the Intel Xeon Phi coprocessor. We also demonstrate a 2000x performance speedup from the seamless integration of SIMD vectorization and parallelization.

Engineering BioBrick vectors from BioBrick parts

Directory of Open Access Journals (Sweden)

Knight Thomas F

2008-04-01

Full Text Available Abstract Background The underlying goal of synthetic biology is to make the process of engineering biological systems easier. Recent work has focused on defining and developing standard biological parts. The technical standard that has gained the most traction in the synthetic biology community is the BioBrick standard for physical composition of genetic parts. Parts that conform to the BioBrick assembly standard are BioBrick standard biological parts. To date, over 2,000 BioBrick parts have been contributed to, and are available from, the Registry of Standard Biological Parts. Results Here we extended the same advantages of BioBrick standard biological parts to the plasmid-based vectors that are used to provide and propagate BioBrick parts. We developed a process for engineering BioBrick vectors from BioBrick parts. We designed a new set of BioBrick parts that encode many useful vector functions. We combined the new parts to make a BioBrick base vector that facilitates BioBrick vector construction. We demonstrated the utility of the process by constructing seven new BioBrick vectors. We also successfully used the resulting vectors to assemble and propagate other BioBrick standard biological parts. Conclusion We extended the principles of part reuse and standardization to BioBrick vectors. As a result, myriad new BioBrick vectors can be readily produced from all existing and newly designed BioBrick parts. We invite the synthetic biology community to (1 use the process to make and share new BioBrick vectors; (2 expand the current collection of BioBrick vector parts; and (3 characterize and improve the available collection of BioBrick vector parts.

Bioreactor production of recombinant herpes simplex virus vectors.

Science.gov (United States)

Knop, David R; Harrell, Heather

2007-01-01

Serotypical application of herpes simplex virus (HSV) vectors to gene therapy (type 1) and prophylactic vaccines (types 1 and 2) has garnered substantial clinical interest recently. HSV vectors and amplicons have also been employed as helper virus constructs for manufacture of the dependovirus adeno-associated virus (AAV). Large quantities of infectious HSV stocks are requisite for these therapeutic applications, requiring a scalable vector manufacturing and processing platform comprised of unit operations which accommodate the fragility of HSV. In this study, production of a replication deficient rHSV-1 vector bearing the rep and cap genes of AAV-2 (denoted rHSV-rep2/cap2) was investigated. Adaptation of rHSV production from T225 flasks to a packed bed, fed-batch bioreactor permitted an 1100-fold increment in total vector production without a decrease in specific vector yield (pfu/cell). The fed-batch bioreactor system afforded a rHSV-rep2/cap2 vector recovery of 2.8 x 10(12) pfu. The recovered vector was concentrated by tangential flow filtration (TFF), permitting vector stocks to be formulated at greater than 1.5 x 10(9) pfu/mL.

Cosmological evolution in vector-tensor theories of gravity

International Nuclear Information System (INIS)

Beltran Jimenez, Jose; Maroto, Antonio L.

2009-01-01

We present a detailed study of the cosmological evolution in general vector-tensor theories of gravity without potential terms. We consider the evolution of the vector field throughout the expansion history of the Universe and carry out a classification of models according to the behavior of the vector field in each cosmological epoch. We also analyze the case in which the Universe is dominated by the vector field, performing a complete analysis of the system phase map and identifying those attracting solutions which give rise to accelerated expansion. Moreover, we consider the evolution in a universe filled with a pressureless fluid in addition to the vector field and study the existence of attractors in which we can have a transition from matter domination to vector domination with accelerated expansion so that the vector field may play the role of dark energy. We find that the existence of solutions with late-time accelerated expansion is a generic prediction of vector-tensor theories and that such solutions typically lead to the presence of future singularities. Finally, limits from local gravity tests are used to get constraints on the value of the vector field at small (Solar System) scales.

n-Characteristic Vector Fields of Contact Manifoldss

OpenAIRE

Hassanzadeh, Babak

2017-01-01

In present paper we define and study $n$-characteristic vector fields. We present definition of Tanaka-Webster connection, then use it for studying the behavior of $n$-characteristic vector fields. Also we show some results about of these vector fields by Tanaka-Webster connection.

Successful vectorization - reactor physics Monte Carlo code

International Nuclear Information System (INIS)

Martin, W.R.

1989-01-01

Most particle transport Monte Carlo codes in use today are based on the ''history-based'' algorithm, wherein one particle history at a time is simulated. Unfortunately, the ''history-based'' approach (present in all Monte Carlo codes until recent years) is inherently scalar and cannot be vectorized. In particular, the history-based algorithm cannot take advantage of vector architectures, which characterize the largest and fastest computers at the current time, vector supercomputers such as the Cray X/MP or IBM 3090/600. However, substantial progress has been made in recent years in developing and implementing a vectorized Monte Carlo algorithm. This algorithm follows portions of many particle histories at the same time and forms the basis for all successful vectorized Monte Carlo codes that are in use today. This paper describes the basic vectorized algorithm along with descriptions of several variations that have been developed by different researchers for specific applications. These applications have been mainly in the areas of neutron transport in nuclear reactor and shielding analysis and photon transport in fusion plasmas. The relative merits of the various approach schemes will be discussed and the present status of known vectorization efforts will be summarized along with available timing results, including results from the successful vectorization of 3-D general geometry, continuous energy Monte Carlo. (orig.)

A study of biorthogonal multiple vector-valued wavelets

International Nuclear Information System (INIS)

Han Jincang; Cheng Zhengxing; Chen Qingjiang

2009-01-01

The notion of vector-valued multiresolution analysis is introduced and the concept of biorthogonal multiple vector-valued wavelets which are wavelets for vector fields, is introduced. It is proved that, like in the scalar and multiwavelet case, the existence of a pair of biorthogonal multiple vector-valued scaling functions guarantees the existence of a pair of biorthogonal multiple vector-valued wavelet functions. An algorithm for constructing a class of compactly supported biorthogonal multiple vector-valued wavelets is presented. Their properties are investigated by means of operator theory and algebra theory and time-frequency analysis method. Several biorthogonality formulas regarding these wavelet packets are obtained.

3-D Vector Flow Imaging

DEFF Research Database (Denmark)

Holbek, Simon

, if this significant reduction in the element count can still provide precise and robust 3-D vector flow estimates in a plane. The study concludes that the RC array is capable of estimating precise 3-D vector flow both in a plane and in a volume, despite the low channel count. However, some inherent new challenges...... ultrasonic vector flow estimation and bring it a step closer to a clinical application. A method for high frame rate 3-D vector flow estimation in a plane using the transverse oscillation method combined with a 1024 channel 2-D matrix array is presented. The proposed method is validated both through phantom...... hampers the task of real-time processing. In a second study, some of the issue with the 2-D matrix array are solved by introducing a 2-D row-column (RC) addressing array with only 62 + 62 elements. It is investigated both through simulations and via experimental setups in various flow conditions...

Black holes in vector-tensor theories

Energy Technology Data Exchange (ETDEWEB)

Heisenberg, Lavinia [Institute for Theoretical Studies, ETH Zurich, Clausiusstrasse 47, 8092 Zurich (Switzerland); Kase, Ryotaro; Tsujikawa, Shinji [Department of Physics, Faculty of Science, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601 (Japan); Minamitsuji, Masato, E-mail: lavinia.heisenberg@eth-its.ethz.ch, E-mail: r.kase@rs.tus.ac.jp, E-mail: masato.minamitsuji@tecnico.ulisboa.pt, E-mail: shinji@rs.kagu.tus.ac.jp [Centro Multidisciplinar de Astrofisica—CENTRA, Departamento de Fisica, Instituto Superior Tecnico—IST, Universidade de Lisboa—UL, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal)

2017-08-01

We study static and spherically symmetric black hole (BH) solutions in second-order generalized Proca theories with nonminimal vector field derivative couplings to the Ricci scalar, the Einstein tensor, and the double dual Riemann tensor. We find concrete Lagrangians which give rise to exact BH solutions by imposing two conditions of the two identical metric components and the constant norm of the vector field. These exact solutions are described by either Reissner-Nordström (RN), stealth Schwarzschild, or extremal RN solutions with a non-trivial longitudinal mode of the vector field. We then numerically construct BH solutions without imposing these conditions. For cubic and quartic Lagrangians with power-law couplings which encompass vector Galileons as the specific cases, we show the existence of BH solutions with the difference between two non-trivial metric components. The quintic-order power-law couplings do not give rise to non-trivial BH solutions regular throughout the horizon exterior. The sixth-order and intrinsic vector-mode couplings can lead to BH solutions with a secondary hair. For all the solutions, the vector field is regular at least at the future or past horizon. The deviation from General Relativity induced by the Proca hair can be potentially tested by future measurements of gravitational waves in the nonlinear regime of gravity.

Investigation of Optimal Integrated Circuit Raster Image Vectorization Method

Directory of Open Access Journals (Sweden)

Leonas Jasevičius

2011-03-01

Full Text Available Visual analysis of integrated circuit layer requires raster image vectorization stage to extract layer topology data to CAD tools. In this paper vectorization problems of raster IC layer images are presented. Various line extraction from raster images algorithms and their properties are discussed. Optimal raster image vectorization method was developed which allows utilization of common vectorization algorithms to achieve the best possible extracted vector data match with perfect manual vectorization results. To develop the optimal method, vectorized data quality dependence on initial raster image skeleton filter selection was assessed.Article in Lithuanian

Environmental management: a re-emerging vector control strategy.

Science.gov (United States)

Ault, S K

1994-01-01

Vector control may be accomplished by environmental management (EM), which consists of permanent or long-term modification of the environment, temporary or seasonal manipulation of the environment, and modifying or changing our life styles and practices to reduce human contact with infective vectors. The primary focus of this paper is EM in the control of human malaria, filariasis, arboviruses, Chagas' disease, and schistosomiasis. Modern EM developed as a discipline based primarily in ecologic principles and lessons learned from the adverse environmental impacts of rural development projects. Strategies such as the suppression of vector populations through the provision of safe water supplies, proper sanitation, solid waste management facilities, sewerage and excreta disposal systems, water manipulation in dams and irrigation systems, vector diversion by zooprophylaxis, and vector exclusion by improved housing, are discussed with appropriate examples. Vectors of malaria, filariasis, Chagas' disease, and schistosomiasis have been controlled by drainage or filling aquatic breeding sites, improved housing and sanitation, the use of expanded polystyrene beads, zooprophylaxis, or the provision of household water supplies. Community participation has been effective in the suppression of dengue vectors in Mexico and the Dominican Republic. Alone or combined with other vector control methods, EM has been proven to be a successful approach to vector control in a number of places. The future of EM in vector control looks promising.

TimesVector: a vectorized clustering approach to the analysis of time series transcriptome data from multiple phenotypes.

Science.gov (United States)

Jung, Inuk; Jo, Kyuri; Kang, Hyejin; Ahn, Hongryul; Yu, Youngjae; Kim, Sun

2017-12-01

Identifying biologically meaningful gene expression patterns from time series gene expression data is important to understand the underlying biological mechanisms. To identify significantly perturbed gene sets between different phenotypes, analysis of time series transcriptome data requires consideration of time and sample dimensions. Thus, the analysis of such time series data seeks to search gene sets that exhibit similar or different expression patterns between two or more sample conditions, constituting the three-dimensional data, i.e. gene-time-condition. Computational complexity for analyzing such data is very high, compared to the already difficult NP-hard two dimensional biclustering algorithms. Because of this challenge, traditional time series clustering algorithms are designed to capture co-expressed genes with similar expression pattern in two sample conditions. We present a triclustering algorithm, TimesVector, specifically designed for clustering three-dimensional time series data to capture distinctively similar or different gene expression patterns between two or more sample conditions. TimesVector identifies clusters with distinctive expression patterns in three steps: (i) dimension reduction and clustering of time-condition concatenated vectors, (ii) post-processing clusters for detecting similar and distinct expression patterns and (iii) rescuing genes from unclassified clusters. Using four sets of time series gene expression data, generated by both microarray and high throughput sequencing platforms, we demonstrated that TimesVector successfully detected biologically meaningful clusters of high quality. TimesVector improved the clustering quality compared to existing triclustering tools and only TimesVector detected clusters with differential expression patterns across conditions successfully. The TimesVector software is available at http://biohealth.snu.ac.kr/software/TimesVector/. sunkim.bioinfo@snu.ac.kr. Supplementary data are available at

Vector assembly of colloids on monolayer substrates

Science.gov (United States)

Jiang, Lingxiang; Yang, Shenyu; Tsang, Boyce; Tu, Mei; Granick, Steve

2017-06-01

The key to spontaneous and directed assembly is to encode the desired assembly information to building blocks in a programmable and efficient way. In computer graphics, raster graphics encodes images on a single-pixel level, conferring fine details at the expense of large file sizes, whereas vector graphics encrypts shape information into vectors that allow small file sizes and operational transformations. Here, we adapt this raster/vector concept to a 2D colloidal system and realize `vector assembly' by manipulating particles on a colloidal monolayer substrate with optical tweezers. In contrast to raster assembly that assigns optical tweezers to each particle, vector assembly requires a minimal number of optical tweezers that allow operations like chain elongation and shortening. This vector approach enables simple uniform particles to form a vast collection of colloidal arenes and colloidenes, the spontaneous dissociation of which is achieved with precision and stage-by-stage complexity by simply removing the optical tweezers.

Herbivore arthropods benefit from vectoring plant viruses

NARCIS (Netherlands)

Belliure, B.; Janssen, A.; Maris, P.C.; Peters, D.; Sabelis, M.W.

2005-01-01

Plants infected with pathogens often attract the pathogens' vectors, but it is not clear if this is advantageous to the vectors. We therefore quantified the direct and indirect (through the host plant) effects of a pathogen on its vector. A positive direct effect of the plant-pathogenic Tomato

Genetic modification of hematopoietic cells using retroviral and lentiviral vectors: safety considerations for vector design and delivery into target cells.

Science.gov (United States)

Dropulic, Boro

2005-07-01

The recent development of leukemia in three patients following retroviral vector gene transfer in hematopoietic stem cells, resulting in the death of one patient, has raised safety concerns for the use of integrating gene transfer vectors for human gene therapy. This review discusses these serious adverse events from the perspective of whether restrictions on vector design and vector-modified target cells are warranted at this time. A case is made against presently establishing specific restrictions for vector design and transduced cells; rather, their safety should be ascertained by empiric evaluation in appropriate preclinical models on a case-by-case basis. Such preclinical data, coupled with proper informed patient consent and a risk-benefit ratio analysis, provide the best available prospective evaluation of gene transfer vectors prior to their translation into the clinic.

Meromorphic Vector Fields and Circle Packings

DEFF Research Database (Denmark)

Dias, Kealey

The objective of the Ph.D. project is to initiate a classification of bifurcations of meromorphic vector fields and to clarify their relation to circle packings. Technological applications are to image analysis and to effective grid generation using discrete conformal mappings. The two branches...... of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions or meromorphic (allowing poles...... as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic vector fields. Restricting...

Characterizing Convexity of Games using Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2003-01-01

In this paper we study the relation between convexity of TU games and marginal vectors.We show that if specfic marginal vectors are core elements, then the game is convex.We characterize sets of marginal vectors satisfying this property, and we derive the formula for the minimum number of marginal

How effective is integrated vector management against malaria and lymphatic filariasis where the diseases are transmitted by the same vector?

OpenAIRE

Stone, C.; Lindsay, S.W.; Chitnis, N.

2014-01-01

Background: The opportunity to integrate vector management across multiple vector-borne diseases is particularly plausible for malaria and lymphatic filariasis (LF) control where both diseases are transmitted by the same vector. To date most examples of integrated control targeting these diseases have been unanticipated consequences of malaria vector control, rather than planned strategies that aim to maximize the efficacy and take the complex ecological and biological interactions between th...

Two-dimensional gauge model with vector U(1) and axial-vector U(1) symmetries

International Nuclear Information System (INIS)

Watabiki, Y.

1989-01-01

We have succeeded in constructing a two-dimensional gauge model with both vector U(1) and axial-vector U(1) symmetries. This model is exactly solvable. The Schwinger term vanishes in this model as a consequence of the above symmetries, and negative-norm states appear. However, the norms of physical states are always positive semidefinite due to the gauge symmetries

Air travel and vector-borne disease movement.

Science.gov (United States)

Tatem, A J; Huang, Z; Das, A; Qi, Q; Roth, J; Qiu, Y

2012-12-01

Recent decades have seen substantial expansions in the global air travel network and rapid increases in traffic volumes. The effects of this are well studied in terms of the spread of directly transmitted infections, but the role of air travel in the movement of vector-borne diseases is less well understood. Increasingly however, wider reaching surveillance for vector-borne diseases and our improving abilities to map the distributions of vectors and the diseases they carry, are providing opportunities to better our understanding of the impact of increasing air travel. Here we examine global trends in the continued expansion of air transport and its impact upon epidemiology. Novel malaria and chikungunya examples are presented, detailing how geospatial data in combination with information on air traffic can be used to predict the risks of vector-borne disease importation and establishment. Finally, we describe the development of an online tool, the Vector-Borne Disease Airline Importation Risk (VBD-Air) tool, which brings together spatial data on air traffic and vector-borne disease distributions to quantify the seasonally changing risks for importation to non-endemic regions. Such a framework provides the first steps towards an ultimate goal of adaptive management based on near real time flight data and vector-borne disease surveillance.

Bunyavirus-Vector Interactions

Directory of Open Access Journals (Sweden)

Kate McElroy Horne

2014-11-01

Full Text Available The Bunyaviridae family is comprised of more than 350 viruses, of which many within the Hantavirus, Orthobunyavirus, Nairovirus, Tospovirus, and Phlebovirus genera are significant human or agricultural pathogens. The viruses within the Orthobunyavirus, Nairovirus, and Phlebovirus genera are transmitted by hematophagous arthropods, such as mosquitoes, midges, flies, and ticks, and their associated arthropods not only serve as vectors but also as virus reservoirs in many cases. This review presents an overview of several important emerging or re-emerging bunyaviruses and describes what is known about bunyavirus-vector interactions based on epidemiological, ultrastructural, and genetic studies of members of this virus family.

Lyapunov, singular and bred vectors in a multi-scale system: an empirical exploration of vectors related to instabilities

International Nuclear Information System (INIS)

Norwood, Adrienne; Kalnay, Eugenia; Ide, Kayo; Yang, Shu-Chih; Wolfe, Christopher

2013-01-01

We compute and compare the three types of vectors frequently used to explore the instability properties of dynamical models, namely Lyapunov vectors (LVs), singular vectors (SVs) and bred vectors (BVs) in two systems, using the Wolfe–Samelson (2007 Tellus A 59 355–66) algorithm to compute all of the Lyapunov vectors. The first system is the Lorenz (1963 J. Atmos. Sci. 20 130–41) three-variable model. Although the leading Lyapunov vector, LV1, grows fastest globally, the second Lyapunov vector, LV2, which has zero growth globally, often grows faster than LV1 locally. Whenever this happens, BVs grow closer to LV2, suggesting that in larger atmospheric or oceanic models where several instabilities can grow in different areas of the world, BVs will grow toward the fastest growing local unstable mode. A comparison of their growth rates at different times shows that all three types of dynamical vectors have the ability to predict regime changes and the duration of the new regime based on their growth rates in the last orbit of the old regime, as shown for BVs by Evans et al (2004 Bull. Am. Meteorol. Soc. 520–4). LV1 and BVs have similar predictive skill, LV2 has a tendency to produce false alarms, and even LV3 shows that maximum decay is also associated with regime change. Initial and final SVs grow much faster and are the most accurate predictors of regime change, although the characteristics of the initial SVs are strongly dependent on the length of the optimization window. The second system is the toy ‘ocean-atmosphere’ model developed by Peña and Kalnay (2004 Nonlinear Process. Geophys. 11 319–27) coupling three Lorenz (1963 J. Atmos. Sci. 20 130–41) systems with different time scales, in order to test the effects of fast and slow modes of growth on the dynamical vectors. A fast ‘extratropical atmosphere’ is weakly coupled to a fast ‘tropical atmosphere’ which is, in turn, strongly coupled to a slow ‘ocean’ system, the latter coupling

Generalized 2-vector spaces and general linear 2-groups

OpenAIRE

Elgueta, Josep

2008-01-01

In this paper a notion of {\\it generalized 2-vector space} is introduced which includes Kapranov and Voevodsky 2-vector spaces. Various kinds of generalized 2-vector spaces are considered and examples are given. The existence of non free generalized 2-vector spaces and of generalized 2-vector spaces which are non Karoubian (hence, non abelian) categories is discussed, and it is shown how any generalized 2-vector space can be identified with a full subcategory of an (abelian) functor category ...

The charge form factor of the neutron from sup 2 H-vector, (e-vector, e' n)p

CERN Document Server

Passchier, I; Szczerba, D; Alarcon, R; Bauer, T S; Boersma, D J; Van der Brand, J F J; Bulten, H J; Ferro-Luzzi, M; Higinbotham, D W; Jager, C W D; Klous, S; Kolster, H; Lang, J; Nikolenko, D M; Nooren, G J; Norum, B E; Poolman, H R; Rachek, Igor A; Simani, M C; Six, E; Vries, H D; Wang, K; Zhou, Z L

2000-01-01

We report on the first measurement of spin-correlation parameters in quasifree electron scattering from vector-polarized deuterium. Polarized electrons were injected into an electron storage ring at a beam energy of 720 MeV. A Siberian snake was employed to preserve longitudinal polarization at the interaction point. Vector-polarized deuterium was produced by an atomic beam source and injected into an open-ended cylindrical cell, internal to the electron storage ring. The spin correlation parameter A sup V sub e sub d was measured for the reaction sup 2 H-vector, (e-vector, e'n)p at a four-momentum transfer squared of 0.21 (GeV/c) sup 2 from which a value for the charge form factor of the neutron was extracted.

Construction of expression vectors carrying mouse peroxisomal ...

African Journals Online (AJOL)

The aim of this study was to construct expression vectors carrying mouse peroxisomal protein gene (PEP-cDNA) in prokaryotic and mammalian expression vectors in ... pGEX6p2-PEP and pUcD3-FLAG-PEP constructed vectors were transformed into the one shot TOP10 and JM105 bacterial competent cells, respectively.

Vector Fields and Flows on Differentiable Stacks

DEFF Research Database (Denmark)

A. Hepworth, Richard

2009-01-01

This paper introduces the notions of vector field and flow on a general differentiable stack. Our main theorem states that the flow of a vector field on a compact proper differentiable stack exists and is unique up to a uniquely determined 2-cell. This extends the usual result on the existence...... of vector fields....

Extremal vectors and rectifiability | Enflo | Quaestiones Mathematicae

African Journals Online (AJOL)

Extremal vectors and rectifiability. ... The concept of extremal vectors of a linear operator with a dense range but not onto on a Hilbert space was introduced by P. Enflo in 1996 as a new approach to study invariant subspaces ... We show that in general curves that map numbers to backward minimal vectors are not rectifiable.

Integrated vector management for malaria control

Directory of Open Access Journals (Sweden)

Impoinvil Daniel E

2008-12-01

Full Text Available Abstract Integrated vector management (IVM is defined as "a rational decision-making process for the optimal use of resources for vector control" and includes five key elements: 1 evidence-based decision-making, 2 integrated approaches 3, collaboration within the health sector and with other sectors, 4 advocacy, social mobilization, and legislation, and 5 capacity-building. In 2004, the WHO adopted IVM globally for the control of all vector-borne diseases. Important recent progress has been made in developing and promoting IVM for national malaria control programmes in Africa at a time when successful malaria control programmes are scaling-up with insecticide-treated nets (ITN and/or indoor residual spraying (IRS coverage. While interventions using only ITNs and/or IRS successfully reduce transmission intensity and the burden of malaria in many situations, it is not clear if these interventions alone will achieve those critical low levels that result in malaria elimination. Despite the successful employment of comprehensive integrated malaria control programmes, further strengthening of vector control components through IVM is relevant, especially during the "end-game" where control is successful and further efforts are required to go from low transmission situations to sustained local and country-wide malaria elimination. To meet this need and to ensure sustainability of control efforts, malaria control programmes should strengthen their capacity to use data for decision-making with respect to evaluation of current vector control programmes, employment of additional vector control tools in conjunction with ITN/IRS tactics, case-detection and treatment strategies, and determine how much and what types of vector control and interdisciplinary input are required to achieve malaria elimination. Similarly, on a global scale, there is a need for continued research to identify and evaluate new tools for vector control that can be integrated with

Applications of the conserved vector current theory and the partially conserved axial-vector current theory to nuclear beta-decays

International Nuclear Information System (INIS)

Tint, M.

The contribution of the mesonic exchange effect to the conserved vector current in the first forbidden β-decay of Ra E is estimated under the headings: (1) The conserved vector current. (2) The CVC theory and the first forbidden β-decays. (3) Shell model calculations of some matrix-elements. (4) Direct calculation of the exchange term. Considering the mesonic exchange effect in the axial vector-current of β-decay the partially conserved axial vector current theory and experimental results of the process p + p → d + π + are examined. (U.K.)

Feature Vector Construction Method for IRIS Recognition

Science.gov (United States)

Odinokikh, G.; Fartukov, A.; Korobkin, M.; Yoo, J.

2017-05-01

One of the basic stages of iris recognition pipeline is iris feature vector construction procedure. The procedure represents the extraction of iris texture information relevant to its subsequent comparison. Thorough investigation of feature vectors obtained from iris showed that not all the vector elements are equally relevant. There are two characteristics which determine the vector element utility: fragility and discriminability. Conventional iris feature extraction methods consider the concept of fragility as the feature vector instability without respect to the nature of such instability appearance. This work separates sources of the instability into natural and encodinginduced which helps deeply investigate each source of instability independently. According to the separation concept, a novel approach of iris feature vector construction is proposed. The approach consists of two steps: iris feature extraction using Gabor filtering with optimal parameters and quantization with separated preliminary optimized fragility thresholds. The proposed method has been tested on two different datasets of iris images captured under changing environmental conditions. The testing results show that the proposed method surpasses all the methods considered as a prior art by recognition accuracy on both datasets.

Vectorization of Monte Carlo particle transport

International Nuclear Information System (INIS)

Burns, P.J.; Christon, M.; Schweitzer, R.; Lubeck, O.M.; Wasserman, H.J.; Simmons, M.L.; Pryor, D.V.

1989-01-01

This paper reports that fully vectorized versions of the Los Alamos National Laboratory benchmark code Gamteb, a Monte Carlo photon transport algorithm, were developed for the Cyber 205/ETA-10 and Cray X-MP/Y-MP architectures. Single-processor performance measurements of the vector and scalar implementations were modeled in a modified Amdahl's Law that accounts for additional data motion in the vector code. The performance and implementation strategy of the vector codes are related to architectural features of each machine. Speedups between fifteen and eighteen for Cyber 205/ETA-10 architectures, and about nine for CRAY X-MP/Y-MP architectures are observed. The best single processor execution time for the problem was 0.33 seconds on the ETA-10G, and 0.42 seconds on the CRAY Y-MP

Horizontal vectorization of electron repulsion integrals.

Science.gov (United States)

Pritchard, Benjamin P; Chow, Edmond

2016-10-30

We present an efficient implementation of the Obara-Saika algorithm for the computation of electron repulsion integrals that utilizes vector intrinsics to calculate several primitive integrals concurrently in a SIMD vector. Initial benchmarks display a 2-4 times speedup with AVX instructions over comparable scalar code, depending on the basis set. Speedup over scalar code is found to be sensitive to the level of contraction of the basis set, and is best for (lAlB|lClD) quartets when lD  = 0 or lB=lD=0, which makes such a vectorization scheme particularly suitable for density fitting. The basic Obara-Saika algorithm, how it is vectorized, and the performance bottlenecks are analyzed and discussed. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

A vector lattice version of Radström's embedding theorem

African Journals Online (AJOL)

Radström's embedding theorem for 'near vector spaces', which are essentially vector spaces without additive inverses, is extended to embeddings of 'near vector lattices', which are essentially vector lattices without additive inverses, into vector lattices. If the 'near vector space' is endowed with a metric, properties on the ...

Search for intermediate vector bosons

International Nuclear Information System (INIS)

Klajn, D.B.; Rubbia, K.; Meer, S.

1983-01-01

Problem of registration and search for intermediate vector bosons is discussed. According to weak-current theory there are three intermediate vector bosons with +1(W + )-1(W - ) and zero (Z 0 ) electric charges. It was suggested to conduct the investigation into particles in 1976 by cline, Rubbia and Makintair using proton-antiproton beams. Major difficulties of the experiment are related to the necessity of formation of sufficient amount of antiparticles and the method of antiproton beam ''cooling'' for the purpose of reduction of its random movements. The stochastic method was suggested by van der Meer in 1968 as one of possible cooling methods. Several large detectors were designed for searching intermediate vector bosons

On vector fields having properties of Reeb fields

OpenAIRE

Hajduk, Boguslaw; Walczak, Rafal

2011-01-01

We study constructions of vector fields with properties which are characteristic to Reeb vector fields of contact forms. In particular, we prove that all closed oriented odd-dimensional manifold have geodesible vector fields.

Vector fields and gravity on the lattice

International Nuclear Information System (INIS)

Khatsymovsky, V.M.

1988-01-01

The problem of discretization of vector field on Regge lattice is considered. Our approach is based on geometrical interpretation of the vector field as the field of infinitesimal coordinate transformation. A discrete version of the vector field action is obtained as a particular case of the continuum action, and it is shown to have the true continuum limit

Visualizing vector field topology in fluid flows

Science.gov (United States)

Helman, James L.; Hesselink, Lambertus

1991-01-01

Methods of automating the analysis and display of vector field topology in general and flow topology in particular are discussed. Two-dimensional vector field topology is reviewed as the basis for the examination of topology in three-dimensional separated flows. The use of tangent surfaces and clipping in visualizing vector field topology in fluid flows is addressed.

[Orthogonal Vector Projection Algorithm for Spectral Unmixing].

Science.gov (United States)

Song, Mei-ping; Xu, Xing-wei; Chang, Chein-I; An, Ju-bai; Yao, Li

2015-12-01

Spectrum unmixing is an important part of hyperspectral technologies, which is essential for material quantity analysis in hyperspectral imagery. Most linear unmixing algorithms require computations of matrix multiplication and matrix inversion or matrix determination. These are difficult for programming, especially hard for realization on hardware. At the same time, the computation costs of the algorithms increase significantly as the number of endmembers grows. Here, based on the traditional algorithm Orthogonal Subspace Projection, a new method called. Orthogonal Vector Projection is prompted using orthogonal principle. It simplifies this process by avoiding matrix multiplication and inversion. It firstly computes the final orthogonal vector via Gram-Schmidt process for each endmember spectrum. And then, these orthogonal vectors are used as projection vector for the pixel signature. The unconstrained abundance can be obtained directly by projecting the signature to the projection vectors, and computing the ratio of projected vector length and orthogonal vector length. Compared to the Orthogonal Subspace Projection and Least Squares Error algorithms, this method does not need matrix inversion, which is much computation costing and hard to implement on hardware. It just completes the orthogonalization process by repeated vector operations, easy for application on both parallel computation and hardware. The reasonability of the algorithm is proved by its relationship with Orthogonal Sub-space Projection and Least Squares Error algorithms. And its computational complexity is also compared with the other two algorithms', which is the lowest one. At last, the experimental results on synthetic image and real image are also provided, giving another evidence for effectiveness of the method.

Applicability of vector processing to large-scale nuclear codes

International Nuclear Information System (INIS)

Ishiguro, Misako; Harada, Hiroo; Matsuura, Toshihiko; Okuda, Motoi; Ohta, Fumio; Umeya, Makoto.

1982-03-01

To meet the growing trend of computational requirements in JAERI, introduction of a high-speed computer with vector processing faculty (a vector processor) is desirable in the near future. To make effective use of a vector processor, appropriate optimization of nuclear codes to pipelined-vector architecture is vital, which will pose new problems concerning code development and maintenance. In this report, vector processing efficiency is assessed with respect to large-scale nuclear codes by examining the following items: 1) The present feature of computational load in JAERI is analyzed by compiling the computer utilization statistics. 2) Vector processing efficiency is estimated for the ten heavily-used nuclear codes by analyzing their dynamic behaviors run on a scalar machine. 3) Vector processing efficiency is measured for the other five nuclear codes by using the current vector processors, FACOM 230-75 APU and CRAY-1. 4) Effectiveness of applying a high-speed vector processor to nuclear codes is evaluated by taking account of the characteristics in JAERI jobs. Problems of vector processors are also discussed from the view points of code performance and ease of use. (author)

Estimation of Motion Vector Fields

DEFF Research Database (Denmark)

Larsen, Rasmus

1993-01-01

This paper presents an approach to the estimation of 2-D motion vector fields from time varying image sequences. We use a piecewise smooth model based on coupled vector/binary Markov random fields. We find the maximum a posteriori solution by simulated annealing. The algorithm generate sample...... fields by means of stochastic relaxation implemented via the Gibbs sampler....

Exotic composite vector boson

International Nuclear Information System (INIS)

Akama, K.; Hattori, T.; Yasue, M.

1991-01-01

An exotic composite vector boson V is introduced in two dynamical models of composite quarks, leptons, W, and Z. One is based on four-Fermi interactions, in which composite vector bosons are regarded as fermion-antifermion bound states and the other is based on the confining SU(2) L gauge model, in which they are given by scalar-antiscalar bound states. Both approaches describe the same effective interactions for the sector of composite quarks, leptons, W, Z, γ, and V

Vector models in RETRAN-02 MOD 2

International Nuclear Information System (INIS)

Kinnersly, S.R.

1985-06-01

The vector momentum model in RETRAN-02 allows momentum flux to be modelled in two dimensions. Vector models in RETRAN-2 are described, including both the actual implementation in the code and the specification given in the code manual. The vector momentum model is described in detail. Other models which use vector quantities include models for volume average flow, volume average slip velocity, volume average phase velocities and fill junction flows. Both code implementations and code manual descriptions are described and inconsistencies noted. The differences between the standard RETRA-02 Mod 2 version and the Winfrith version RETN2204 are noted. (U.K.)

Vector fields satisfying the barycenter property

Directory of Open Access Journals (Sweden)

Lee Manseob

2018-04-01

Full Text Available We show that if a vector field X has the C1 robustly barycenter property then it does not have singularities and it is Axiom A without cycles. Moreover, if a generic C1-vector field has the barycenter property then it does not have singularities and it is Axiom A without cycles. Moreover, we apply the results to the divergence free vector fields. It is an extension of the results of the barycenter property for generic diffeomorphisms and volume preserving diffeomorphisms [1].

Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses

Directory of Open Access Journals (Sweden)

Hiroyuki Mizuguchi

2011-07-01

Full Text Available The major limitation of the clinical use of replication-incompetent adenovirus (Ad vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN, following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs. In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88 and toll-like receptor 9 (TLR9 play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs, which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.

Scalar-vector bootstrap

Energy Technology Data Exchange (ETDEWEB)

Rejon-Barrera, Fernando [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, Postbus 94485, 1090 GL, Amsterdam (Netherlands); Robbins, Daniel [Department of Physics, Texas A& M University,TAMU 4242, College Station, TX 77843 (United States)

2016-01-22

We work out all of the details required for implementation of the conformal bootstrap program applied to the four-point function of two scalars and two vectors in an abstract conformal field theory in arbitrary dimension. This includes a review of which tensor structures make appearances, a construction of the projectors onto the required mixed symmetry representations, and a computation of the conformal blocks for all possible operators which can be exchanged. These blocks are presented as differential operators acting upon the previously known scalar conformal blocks. Finally, we set up the bootstrap equations which implement crossing symmetry. Special attention is given to the case of conserved vectors, where several simplifications occur.

Magnetic vector field tag and seal

Science.gov (United States)

Johnston, Roger G.; Garcia, Anthony R.

2004-08-31

One or more magnets are placed in a container (preferably on objects inside the container) and the magnetic field strength and vector direction are measured with a magnetometer from at least one location near the container to provide the container with a magnetic vector field tag and seal. The location(s) of the magnetometer relative to the container are also noted. If the position of any magnet inside the container changes, then the measured vector fields at the these locations also change, indicating that the tag has been removed, the seal has broken, and therefore that the container and objects inside may have been tampered with. A hollow wheel with magnets inside may also provide a similar magnetic vector field tag and seal. As the wheel turns, the magnets tumble randomly inside, removing the tag and breaking the seal.

Aplicação de técnicas moleculares no monitoramento do vírus da hepatite A em tecido digestivo dissecado de ostras de cultivo

OpenAIRE

Sincero, Thaís Cristine Marques

2005-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina. Programa de Pós-Graduação em Biotecnologia. Com o grande crescimento da malacocultura em Santa Catarina, tornou-se necessário verificar e assegurar a qualidade sanitária destes moluscos, como também da água onde os mesmos são cultivados. Devido à característica de alimentação filtrante, moluscos bivalves podem bioacumular vírus e outros patógenos presentes em águas contaminadas por efluentes. O vírus da Hepatite A (HAV) tem s...

Design of 2D time-varying vector fields.

Science.gov (United States)

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D; Zhang, Eugene

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects.

AAV Vectorization of DSB-mediated Gene Editing Technologies.

Science.gov (United States)

Moser, Rachel J; Hirsch, Matthew L

2016-01-01

Recent work both at the bench and the bedside demonstrate zinc-finger nucleases (ZFNs), CRISPR/Cas9, and other programmable site-specific endonuclease technologies are being successfully utilized within and alongside AAV vectors to induce therapeutically relevant levels of directed gene editing within the human chromosome. Studies from past decades acknowledge that AAV vector genomes are enhanced substrates for homology-directed repair in the presence or absence of targeted DNA damage within the host genome. Additionally, AAV vectors are currently the most efficient format for in vivo gene delivery with no vector related complications in >100 clinical trials for diverse diseases. At the same time, advancements in the design of custom-engineered site-specific endonucleases and the utilization of elucidated endonuclease formats have resulted in efficient and facile genetic engineering for basic science and for clinical therapies. AAV vectors and gene editing technologies are an obvious marriage, using AAV for the delivery of repair substrate and/or a gene encoding a designer endonuclease; however, while efficient delivery and enhanced gene targeting by vector genomes are advantageous, other attributes of AAV vectors are less desirable for gene editing technologies. This review summarizes the various roles that AAV vectors play in gene editing technologies and provides insight into its trending applications for the treatment of genetic diseases.

Leishmania attachment in permissive vectors and the role of sand fly midgut proteins in parasite-vector interaction

OpenAIRE

Dostálová, Anna

2012-01-01

of PhD. thesis named "Leishmania attachment in permissive vectors and the role of sand fly midgut proteins in parasite-vector interaction", Anna Dostálová, 2011 This thesis focuses on the development of protozoan parasites of the genus Leishmania in their insect vectors, sand flies. It sums up results of three projects I was involved in during my PhD studies. Main emphasis was put on permissive sand fly species that support development of various species of Leishmania. Using a novel method of...

Warps, grids and curvature in triple vector bundles

Science.gov (United States)

Flari, Magdalini K.; Mackenzie, Kirill

2018-06-01

A triple vector bundle is a cube of vector bundle structures which commute in the (strict) categorical sense. A grid in a triple vector bundle is a collection of sections of each bundle structure with certain linearity properties. A grid provides two routes around each face of the triple vector bundle, and six routes from the base manifold to the total manifold; the warps measure the lack of commutativity of these routes. In this paper we first prove that the sum of the warps in a triple vector bundle is zero. The proof we give is intrinsic and, we believe, clearer than the proof using decompositions given earlier by one of us. We apply this result to the triple tangent bundle T^3M of a manifold and deduce (as earlier) the Jacobi identity. We further apply the result to the triple vector bundle T^2A for a vector bundle A using a connection in A to define a grid in T^2A . In this case the curvature emerges from the warp theorem.

Higgs decays and brane gravi-vectors

International Nuclear Information System (INIS)

Clark, T. E.; Liu Boyang; Love, S. T.; Xiong, C.; Veldhuis, T. ter

2008-01-01

Higgs boson decays in flexible brane world models with stable, massive gravi-vectors are considered. Such vectors couple bilinearly to the standard model fields through either the standard model energy-momentum tensor, the weak hypercharge field strength, or the Higgs scalar. The role of the coupling involving the extrinsic curvature is highlighted. It is found that within the presently allowed parameter space, the decay rate of the Higgs into two gravi-vectors (which would appear as an invisible Higgs decay) can be comparable to the rate for any of the standard model decay modes.

Robust Pseudo-Hierarchical Support Vector Clustering

DEFF Research Database (Denmark)

Hansen, Michael Sass; Sjöstrand, Karl; Olafsdóttir, Hildur

2007-01-01

Support vector clustering (SVC) has proven an efficient algorithm for clustering of noisy and high-dimensional data sets, with applications within many fields of research. An inherent problem, however, has been setting the parameters of the SVC algorithm. Using the recent emergence of a method...... for calculating the entire regularization path of the support vector domain description, we propose a fast method for robust pseudo-hierarchical support vector clustering (HSVC). The method is demonstrated to work well on generated data, as well as for detecting ischemic segments from multidimensional myocardial...

Duality in vector optimization

CERN Document Server

Bot, Radu Ioan

2009-01-01

This book presents fundamentals and comprehensive results regarding duality for scalar, vector and set-valued optimization problems in a general setting. After a preliminary chapter dedicated to convex analysis and minimality notions of sets with respect to partial orderings induced by convex cones a chapter on scalar conjugate duality follows. Then investigations on vector duality based on scalar conjugacy are made. Weak, strong and converse duality statements are delivered and connections to classical results from the literature are emphasized. One chapter is exclusively consecrated to the s

First report of diarrheic shellfish toxins in mollusks from Buenos Aires province (Argentina associated with dinophysis spp.: evidence of okadaic acid, dinophysistoxin-1 and their acylderivatives

Directory of Open Access Journals (Sweden)

Eugenia A Sar

2012-06-01

Full Text Available In January 2010, the toxin-producing dinoflagellates Dinophysis acuminata and D. caudata (10³ cells·l-1 were detected in Mar Azul during routine plankton monitoring in Buenos Aires Province coastal waters, Argentina. Wild clams Mesodesma mactroides and Donax hanleyanus from Mar Azul intertidal beach, which are part of the diet for local inhabitants and tourists, tested positive with the offcial lipophilic mouse bioassay. This paper focuses on the detection of Diarrhetic Shellfsh Poison (DSP toxins in these samples using a HPLC-FLD pre column derivatization procedure. The data showed that shellfish were contaminated with complex DSP toxin profiles composed of Okadaic Acid (OA, Dinophysistoxin-1 (DTX-1, Acyl-Dinophysistoxin-1 (Acyl-DTX-1 and Acyl-Okadaic Acid (Acyl-OA. The DSP toxins found in this study produce diarrhea symptoms consistent with those experienced by patients who had ingested cooked shellfish in January. This is the first report of Acyl-derivatives in South American Atlantic shellfish samples and of OA in Argentinean shellfish samples.Primer reporte de toxinas diarreicas de moluscos en bivalvos de la Provincia de Buenos Aires (Argentina asociado con Dinophysis spp.: evidencia de Ácido Okadaico, Dinophysistoxina-1 y sus acyl-derivados. En enero de 2010, los dinoflagelados productores de toxinas Dinophysis acuminata y D. caudata (10³ cells·l-1 fueron detectados en Mar Azul durante un monitoreo rutinario de fitoplancton realizado en aguas costeras de la Provincia de Buenos Aires, Argentina. Mesodesma mactroides (almeja amarilla y Donax hanleyanus (berberecho del intermareal de Mar Azul, que son parte de la dieta de los habitantes del lugar y de turistas, dieron resultado positivo para toxinas lipofílicas mediante bioensayo ratón. Este trabajo está focalizado en la detección de Toxinas Diarreicas de Moluscos (DSP en muestras colectadas durante el evento de toxicidad usando un HPLC-FLD con procedimiento de derivatizaci

Polarization coupling of vector Bessel–Gaussian beams

International Nuclear Information System (INIS)

Takeuchi, Ryushi; Kozawa, Yuichi; Sato, Shunichi

2013-01-01

We report polarization coupling of radial and azimuthal electric field components of a vector light beam as predicted by the fact that the vector Helmholtz equation is expressed as coupled differential equations in cylindrical coordinates. To clearly observe the polarization variation of a beam as it propagates, higher order transverse modes of a vector Bessel–Gaussian beam were generated by a gain distribution modulation technique, which created a narrow ring-shaped gain region in a Nd:YVO 4 crystal. The polarization coupling was confirmed by the observation that the major polarization component of a vector Bessel–Gaussian beam alternates between radial and azimuthal components along with the propagation. (paper)

Vectorization, parallelization and porting of nuclear codes on the VPP500 system (vectorization). Progress report fiscal 1996

Energy Technology Data Exchange (ETDEWEB)

Nemoto, Toshiyuki; Kawai, Wataru [Fujitsu Ltd., Tokyo (Japan); Kawasaki, Nobuo [and others

1997-12-01

Several computer codes in the nuclear field have been vectorized, parallelized and transported on the FUJITSU VPP500 system at Center for Promotion of Computational Science and Engineering in Japan Atomic Energy Research Institute. These results are reported in 3 parts, i.e., the vectorization part, the parallelization part and the porting part. In this report, we describe the vectorization. In this vectorization part, the vectorization of two and three dimensional discrete ordinates simulation code DORT-TORT, gas dynamics analysis code FLOWGR and relativistic Boltzmann-Uehling-Uhlenbeck simulation code RBUU are described. In the parallelization part, the parallelization of 2-Dimensional relativistic electromagnetic particle code EM2D, Cylindrical Direct Numerical Simulation code CYLDNS and molecular dynamics code for simulating radiation damages in diamond crystals DGR are described. And then, in the porting part, the porting of reactor safety analysis code RELAP5/MOD3.2 and RELAP5/MOD3.2.1.2, nuclear data processing system NJOY and 2-D multigroup discrete ordinate transport code TWOTRAN-II are described. And also, a survey for the porting of command-driven interactive data analysis plotting program IPLOT are described. (author)

VECTOR INTEGRATION

NARCIS (Netherlands)

Thomas, E. G. F.

2012-01-01

This paper deals with the theory of integration of scalar functions with respect to a measure with values in a, not necessarily locally convex, topological vector space. It focuses on the extension of such integrals from bounded measurable functions to the class of integrable functions, proving

Axial vector mass spectrum and mixing angles

International Nuclear Information System (INIS)

Caffarelli, R.V.; Kang, K.

1976-01-01

Spectral sum rules of the axial-vector current and axial-vector current-pseudoscalar field are used to study the axial-vector mass spectrum and mixing angles, as well as the decay constants and mixing angles of the pseudoscalar mesons. In general, the result is quite persuasive for the existence of the Jsup(PC) = 1 ++ multiplet in which one has a canonical D-E mixing. (Auth.)

Matrix elements of a hyperbolic vector operator under SO(2,1)

International Nuclear Information System (INIS)

Zettili, N.; Boukahil, A.

2003-01-01

We deal here with the use of Wigner–Eckart type arguments to calculate the matrix elements of a hyperbolic vector operator V-vector by expressing them in terms of reduced matrix elements. In particular, we focus on calculating the matrix elements of this vector operator within the basis of the hyperbolic angular momentum T-vector whose components T-vector 1 , T-vector 2 , T-vector 3 satisfy an SO(2,1) Lie algebra. We show that the commutation rules between the components of V-vector and T-vector can be inferred from the algebra of ordinary angular momentum. We then show that, by analogy to the Wigner–Eckart theorem, we can calculate the matrix elements of V-vector within a representation where T-vector 2 and T-vector 3 are jointly diagonal. (author)

Vector and Raster Data Storage Based on Morton Code

Science.gov (United States)

Zhou, G.; Pan, Q.; Yue, T.; Wang, Q.; Sha, H.; Huang, S.; Liu, X.

2018-05-01

Even though geomatique is so developed nowadays, the integration of spatial data in vector and raster formats is still a very tricky problem in geographic information system environment. And there is still not a proper way to solve the problem. This article proposes a method to interpret vector data and raster data. In this paper, we saved the image data and building vector data of Guilin University of Technology to Oracle database. Then we use ADO interface to connect database to Visual C++ and convert row and column numbers of raster data and X Y of vector data to Morton code in Visual C++ environment. This method stores vector and raster data to Oracle Database and uses Morton code instead of row and column and X Y to mark the position information of vector and raster data. Using Morton code to mark geographic information enables storage of data make full use of storage space, simultaneous analysis of vector and raster data more efficient and visualization of vector and raster more intuitive. This method is very helpful for some situations that need to analyse or display vector data and raster data at the same time.

Structuring Stokes correlation functions using vector-vortex beam

Science.gov (United States)

Kumar, Vijay; Anwar, Ali; Singh, R. P.

2018-01-01

Higher order statistical correlations of the optical vector speckle field, formed due to scattering of a vector-vortex beam, are explored. Here, we report on the experimental construction of the Stokes parameters covariance matrix, consisting of all possible spatial Stokes parameters correlation functions. We also propose and experimentally realize a new Stokes correlation functions called Stokes field auto correlation functions. It is observed that the Stokes correlation functions of the vector-vortex beam will be reflected in the respective Stokes correlation functions of the corresponding vector speckle field. The major advantage of proposing Stokes correlation functions is that the Stokes correlation function can be easily tuned by manipulating the polarization of vector-vortex beam used to generate vector speckle field and to get the phase information directly from the intensity measurements. Moreover, this approach leads to a complete experimental Stokes characterization of a broad range of random fields.

Pair production of intermediate vector bosons

International Nuclear Information System (INIS)

Mikaelian, K.O.

1979-01-01

The production of intermediate vector boson pairs W + W - , Z 0 Z 0 , W +- Z 0 and W +- γ in pp and p anti p collisions is discussed. The motivation is to detect the self-interactions among the four intermediate vector bosons

Multithreading in vector processors

Science.gov (United States)

Evangelinos, Constantinos; Kim, Changhoan; Nair, Ravi

2018-01-16

In one embodiment, a system includes a processor having a vector processing mode and a multithreading mode. The processor is configured to operate on one thread per cycle in the multithreading mode. The processor includes a program counter register having a plurality of program counters, and the program counter register is vectorized. Each program counter in the program counter register represents a distinct corresponding thread of a plurality of threads. The processor is configured to execute the plurality of threads by activating the plurality of program counters in a round robin cycle.

Sums and Gaussian vectors

CERN Document Server

Yurinsky, Vadim Vladimirovich

1995-01-01

Surveys the methods currently applied to study sums of infinite-dimensional independent random vectors in situations where their distributions resemble Gaussian laws. Covers probabilities of large deviations, Chebyshev-type inequalities for seminorms of sums, a method of constructing Edgeworth-type expansions, estimates of characteristic functions for random vectors obtained by smooth mappings of infinite-dimensional sums to Euclidean spaces. A self-contained exposition of the modern research apparatus around CLT, the book is accessible to new graduate students, and can be a useful reference for researchers and teachers of the subject.

Free topological vector spaces

OpenAIRE

Gabriyelyan, Saak S.; Morris, Sidney A.

2016-01-01

We define and study the free topological vector space $\\mathbb{V}(X)$ over a Tychonoff space $X$. We prove that $\\mathbb{V}(X)$ is a $k_\\omega$-space if and only if $X$ is a $k_\\omega$-space. If $X$ is infinite, then $\\mathbb{V}(X)$ contains a closed vector subspace which is topologically isomorphic to $\\mathbb{V}(\\mathbb{N})$. It is proved that if $X$ is a $k$-space, then $\\mathbb{V}(X)$ is locally convex if and only if $X$ is discrete and countable. If $X$ is a metrizable space it is shown ...

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D.; Zhang, Eugene

2012-01-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Two-host, two-vector basic reproduction ratio (R(0 for bluetongue.

Directory of Open Access Journals (Sweden)

Joanne Turner

Full Text Available Mathematical formulations for the basic reproduction ratio (R(0 exist for several vector-borne diseases. Generally, these are based on models of one-host, one-vector systems or two-host, one-vector systems. For many vector borne diseases, however, two or more vector species often co-occur and, therefore, there is a need for more complex formulations. Here we derive a two-host, two-vector formulation for the R(0 of bluetongue, a vector-borne infection of ruminants that can have serious economic consequences; since 1998 for example, it has led to the deaths of well over 1 million sheep in Europe alone. We illustrate our results by considering the situation in South Africa, where there are two major hosts (sheep, cattle and two vector species with differing ecologies and competencies as vectors, for which good data exist. We investigate the effects on R(0 of differences in vector abundance, vector competence and vector host preference between vector species. Our results indicate that R(0 can be underestimated if we assume that there is only one vector transmitting the infection (when there are in fact two or more and/or vector host preferences are overlooked (unless the preferred host is less beneficial or more abundant. The two-host, one-vector formula provides a good approximation when the level of cross-infection between vector species is very small. As this approaches the level of intraspecies infection, a combination of the two-host, one-vector R(0 for each vector species becomes a better estimate. Otherwise, particularly when the level of cross-infection is high, the two-host, two-vector formula is required for accurate estimation of R(0. Our results are equally relevant to Europe, where at least two vector species, which co-occur in parts of the south, have been implicated in the recent epizootic of bluetongue.

Thresholds and Smooth Transitions in Vector Autoregressive Models

DEFF Research Database (Denmark)

Hubrich, Kirstin; Teräsvirta, Timo

This survey focuses on two families of nonlinear vector time series models, the family of Vector Threshold Regression models and that of Vector Smooth Transition Regression models. These two model classes contain incomplete models in the sense that strongly exogeneous variables are allowed in the...

Examples of in-vivo blood vector velocity estimation

DEFF Research Database (Denmark)

Udesen, Jesper; Nielsen, Michael Bachmann; Nielsen, Kristian R.

2007-01-01

In this paper examples of in-vivo blood vector velocity images of the carotid artery are presented. The transverse oscillation (TO) method for blood vector velocity estimation has been used to estimate the vector velocities and the method is first evaluated in a circulating flowrig where...

Killing vectors in empty space algebraically special metrics. II

International Nuclear Information System (INIS)

Held, A.

1976-01-01

Empty space algebraically special metrics possessing an expanding degenerate principal null vector and Killing vectors are investigated. Attention is centered on that class of Killing vector (called nonpreferred) which is necessarily spacelike in the asymptotic region. A detailed analysis of the relationship between the Petrov--Penrose classification and these Killing vectors is carried out

Vectorization of three-dimensional neutron diffusion code CITATION

International Nuclear Information System (INIS)

Harada, Hiroo; Ishiguro, Misako

1985-01-01

Three-dimensional multi-group neutron diffusion code CITATION has been widely used for reactor criticality calculations. The code is expected to be run at a high speed by using recent vector supercomputers, when it is appropriately vectorized. In this paper, vectorization methods and their effects are described for the CITATION code. Especially, calculation algorithms suited for vectorization of the inner-outer iterative calculations which spend most of the computing time are discussed. The SLOR method, which is used in the original CITATION code, and the SOR method, which is adopted in the revised code, are vectorized by odd-even mesh ordering. The vectorized CITATION code is executed on the FACOM VP-100 and VP-200 computers, and is found to run over six times faster than the original code for a practical-scale problem. The initial value of the relaxation factor and the number of inner-iterations given as input data are also investigated since the computing time depends on these values. (author)

Progresses towards safe and efficient gene therapy vectors.

Science.gov (United States)

Chira, Sergiu; Jackson, Carlo S; Oprea, Iulian; Ozturk, Ferhat; Pepper, Michael S; Diaconu, Iulia; Braicu, Cornelia; Raduly, Lajos-Zsolt; Calin, George A; Berindan-Neagoe, Ioana

2015-10-13

The emergence of genetic engineering at the beginning of the 1970's opened the era of biomedical technologies, which aims to improve human health using genetic manipulation techniques in a clinical context. Gene therapy represents an innovating and appealing strategy for treatment of human diseases, which utilizes vehicles or vectors for delivering therapeutic genes into the patients' body. However, a few past unsuccessful events that negatively marked the beginning of gene therapy resulted in the need for further studies regarding the design and biology of gene therapy vectors, so that this innovating treatment approach can successfully move from bench to bedside. In this paper, we review the major gene delivery vectors and recent improvements made in their design meant to overcome the issues that commonly arise with the use of gene therapy vectors. At the end of the manuscript, we summarized the main advantages and disadvantages of common gene therapy vectors and we discuss possible future directions for potential therapeutic vectors.

Application of Bred Vectors To Data Assimilation

Science.gov (United States)

Corazza, M.; Kalnay, E.; Patil, Dj

We introduced a statistic, the BV-dimension, to measure the effective local finite-time dimensionality of the atmosphere. We show that this dimension is often quite low, and suggest that this finding has important implications for data assimilation and the accuracy of weather forecasting (Patil et al, 2001). The original database for this study was the forecasts of the NCEP global ensemble forecasting system. The initial differences between the control forecast and the per- turbed forecasts are called bred vectors. The control and perturbed initial conditions valid at time t=n(t are evolved using the forecast model until time t=(n+1) (t. The differences between the perturbed and the control forecasts are scaled down to their initial amplitude, and constitute the bred vectors valid at (n+1) (t. Their growth rate is typically about 1.5/day. The bred vectors are similar by construction to leading Lya- punov vectors except that they have small but finite amplitude, and they are valid at finite times. The original NCEP ensemble data set has 5 independent bred vectors. We define a local bred vector at each grid point by choosing the 5 by 5 grid points centered at the grid point (a region of about 1100km by 1100km), and using the north-south and east- west velocity components at 500mb pressure level to form a 50 dimensional column vector. Since we have k=5 global bred vectors, we also have k local bred vectors at each grid point. We estimate the effective dimensionality of the subspace spanned by the local bred vectors by performing a singular value decomposition (EOF analysis). The k local bred vector columns form a 50xk matrix M. The singular values s(i) of M measure the extent to which the k column unit vectors making up the matrix M point in the direction of v(i). We define the bred vector dimension as BVDIM={Sum[s(i)]}^2/{Sum[s(i)]^2} For example, if 4 out of the 5 vectors lie along v, and one lies along v, the BV- dimension would be BVDIM[sqrt(4), 1, 0

Vectorization of nuclear codes 90-1

International Nuclear Information System (INIS)

Nonomiya, Iwao; Nemoto, Toshiyuki; Ishiguro, Misako; Harada, Hiroo; Hori, Takeo.

1990-09-01

The vectorization has been made for four codes: SONATINA-2V HTTR version, TRIDOSE, VIENUS, and SCRYU. SONATINA-2V HTTR version is a code for analyzing the dynamic behavior of fuel blocks in the vertical slice of the HTGR (High Temperature Gas-cooled Reactor) core under seismic perturbation, TRIDOSE is a code for calculating environmental tritium concentration and dose, VIENUS is a code for analyzing visco elastic stress of the fuel block of HTTR (High Temperature gas-cooled Test Reactor), and SCRYU is a thermal-hydraulics code with boundary fitted coordinate system. The total speedup ratio of the vectorized versions to the original scalar ones is 5.2 for SONATINA-2V HTTR version. 5.9 ∼ 6.9 for TRIDOSE, 6.7 for VIENUS, 7.6 for SCRYU, respectively. In this report, we describe outline of codes, techniques used for the vectorization, verification of computed results, and speedup effect on the vectorized codes. (author)

Determination of the ratio of axial-vector-to-vector weak coupling constants for beta decay of triton

CERN Document Server

Akulov, Y A

2002-01-01

Data on the chemical shifts of half-lives for atomic and molecular tritium were used to determine the ratio of axial-vector-to-vector weak coupling constants for beta decay of triton (G sub A /G sub V) sub t = -1.2646 +- 0.0035

Projected economic losses due to vector and vector-borne parasitic diseases in livestock of India and its significance in implementing the concept of integrated practices for vector management

Directory of Open Access Journals (Sweden)

B. W. Narladkar

2018-02-01

Full Text Available Broadly, species of arthropods infesting livestock are grouped into flies (biting and non-biting, fleas, lice (biting and sucking, ticks (soft and hard, and mites (burrowing, non-burrowing, and follicular. Among which, biting and non-biting flies and ticks are the potent vectors for many bacterial, viral, rickettsial, and protozoan diseases. Vectors of livestock are having economic significance on three points (1 direct losses from their bite and annoyance, worries, and psychological disturbances produced during the act of biting and feeding, (2 diseases they transmit, and (3 expenditure incurred for their control. Flies such as Culicoides spp. and Musca spp. and various species of hard ticks play important role in disease transmission in addition to their direct effects. For control of vectors, recent concept of integrated pest management (IPM provides the best solution and also addresses the problems related to acaricide resistance and environmental protection from hazardous chemicals. However, to successfully implement the concept of IPM, for each vector species, estimation of two monitory benchmarks, i.e., economic injury level (EIL and economic threshold level (ETL is essential prerequisite. For many vector species and under several circumstances, estimation of EIL and ETL appears to be difficult. Under such scenario, although may not be exact, an approximate estimate can be accrued by taking into account several criteria such as percent prevalence of vectors in a geographical area, percent losses produced, total livestock population, and current prices of livestock products such as milk, meat, and wool. Method for approximate estimation is first time described and elaborated in the present review article.

Projected economic losses due to vector and vector-borne parasitic diseases in livestock of India and its significance in implementing the concept of integrated practices for vector management

Science.gov (United States)

Narladkar, B. W.

2018-01-01

Broadly, species of arthropods infesting livestock are grouped into flies (biting and non-biting), fleas, lice (biting and sucking), ticks (soft and hard), and mites (burrowing, non-burrowing, and follicular). Among which, biting and non-biting flies and ticks are the potent vectors for many bacterial, viral, rickettsial, and protozoan diseases. Vectors of livestock are having economic significance on three points (1) direct losses from their bite and annoyance, worries, and psychological disturbances produced during the act of biting and feeding, (2) diseases they transmit, and (3) expenditure incurred for their control. Flies such as Culicoides spp. and Musca spp. and various species of hard ticks play important role in disease transmission in addition to their direct effects. For control of vectors, recent concept of integrated pest management (IPM) provides the best solution and also addresses the problems related to acaricide resistance and environmental protection from hazardous chemicals. However, to successfully implement the concept of IPM, for each vector species, estimation of two monitory benchmarks, i.e., economic injury level (EIL) and economic threshold level (ETL) is essential prerequisite. For many vector species and under several circumstances, estimation of EIL and ETL appears to be difficult. Under such scenario, although may not be exact, an approximate estimate can be accrued by taking into account several criteria such as percent prevalence of vectors in a geographical area, percent losses produced, total livestock population, and current prices of livestock products such as milk, meat, and wool. Method for approximate estimation is first time described and elaborated in the present review article. PMID:29657396

Construction and evaluation of novel rhesus monkey adenovirus vaccine vectors.

Science.gov (United States)

Abbink, Peter; Maxfield, Lori F; Ng'ang'a, David; Borducchi, Erica N; Iampietro, M Justin; Bricault, Christine A; Teigler, Jeffrey E; Blackmore, Stephen; Parenteau, Lily; Wagh, Kshitij; Handley, Scott A; Zhao, Guoyan; Virgin, Herbert W; Korber, Bette; Barouch, Dan H

2015-02-01

Adenovirus vectors are widely used as vaccine candidates for a variety of pathogens, including HIV-1. To date, human and chimpanzee adenoviruses have been explored in detail as vaccine vectors. The phylogeny of human and chimpanzee adenoviruses is overlapping, and preexisting humoral and cellular immunity to both are exhibited in human populations worldwide. More distantly related adenoviruses may therefore offer advantages as vaccine vectors. Here we describe the primary isolation and vectorization of three novel adenoviruses from rhesus monkeys. The seroprevalence of these novel rhesus monkey adenovirus vectors was extremely low in sub-Saharan Africa human populations, and these vectors proved to have immunogenicity comparable to that of human and chimpanzee adenovirus vaccine vectors in mice. These rhesus monkey adenoviruses phylogenetically clustered with the poorly described adenovirus species G and robustly stimulated innate immune responses. These novel adenoviruses represent a new class of candidate vaccine vectors. Although there have been substantial efforts in the development of vaccine vectors from human and chimpanzee adenoviruses, far less is known about rhesus monkey adenoviruses. In this report, we describe the isolation and vectorization of three novel rhesus monkey adenoviruses. These vectors exhibit virologic and immunologic characteristics that make them attractive as potential candidate vaccine vectors for both HIV-1 and other pathogens. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Modified montmorillonite as vector for gene delivery.

Science.gov (United States)

Lin, Feng-Huei; Chen, Chia-Hao; Cheng, Winston T K; Kuo, Tzang-Fu

2006-06-01

Currently, gene delivery systems can be divided into two parts: viral or non-viral vectors. In general, viral vectors have a higher efficiency on gene delivery. However, they may sometimes provoke mutagenesis and carcinogenesis once re-activating in human body. Lots of non-viral vectors have been developed that tried to solve the problems happened on viral vectors. Unfortunately, most of non-viral vectors showed relatively lower transfection rate. The aim of this study is to develop a non-viral vector for gene delivery system. Montmorillonite (MMT) is one of clay minerals that consist of hydrated aluminum with Si-O tetrahedrons on the bottom of the layer and Al-O(OH)2 octahedrons on the top. The inter-layer space is about 12 A. The room is not enough to accommodate DNA for gene delivery. In the study, the cationic hexadecyltrimethylammonium (HDTMA) will be intercalated into the interlayer of MMT as a layer expander to expand the layer space for DNA accommodation. The optimal condition for the preparation of DNA-HDTMA-MMT is as follows: 1 mg of 1.5CEC HDTMA-MMT was prepared under pH value of 10.7 and with soaking time for 2 h. The DNA molecules can be protected from nuclease degradation, which can be proven by the electrophoresis analysis. DNA was successfully transfected into the nucleus of human dermal fibroblast and expressed enhanced green fluorescent protein (EGFP) gene with green fluorescence emission. The HDTMA-MMT has a great potential as a vector for gene delivery in the future.

Energy-exchange collisions of dark-bright-bright vector solitons.

Science.gov (United States)

Radhakrishnan, R; Manikandan, N; Aravinthan, K

2015-12-01

We find a dark component guiding the practically interesting bright-bright vector one-soliton to two different parametric domains giving rise to different physical situations by constructing a more general form of three-component dark-bright-bright mixed vector one-soliton solution of the generalized Manakov model with nine free real parameters. Moreover our main investigation of the collision dynamics of such mixed vector solitons by constructing the multisoliton solution of the generalized Manakov model with the help of Hirota technique reveals that the dark-bright-bright vector two-soliton supports energy-exchange collision dynamics. In particular the dark component preserves its initial form and the energy-exchange collision property of the bright-bright vector two-soliton solution of the Manakov model during collision. In addition the interactions between bound state dark-bright-bright vector solitons reveal oscillations in their amplitudes. A similar kind of breathing effect was also experimentally observed in the Bose-Einstein condensates. Some possible ways are theoretically suggested not only to control this breathing effect but also to manage the beating, bouncing, jumping, and attraction effects in the collision dynamics of dark-bright-bright vector solitons. The role of multiple free parameters in our solution is examined to define polarization vector, envelope speed, envelope width, envelope amplitude, grayness, and complex modulation of our solution. It is interesting to note that the polarization vector of our mixed vector one-soliton evolves in sphere or hyperboloid depending upon the initial parametric choices.

Vectorization, parallelization and porting of nuclear codes on the VPP500 system (vectorization). Progress report fiscal 1997

International Nuclear Information System (INIS)

Kawasaki, Nobuo; Ogasawara, Shinobu; Adachi, Masaaki; Kume, Etsuo; Ishizuki, Shigeru; Tanabe, Hidenobu; Nemoto, Toshiyuki; Kawai, Wataru; Watanabe, Hideo

1999-05-01

Several computer codes in the nuclear field have been vectorized, parallelized and transported on the FUJITSU VPP500 system and/or the AP3000 system at Center for Promotion of Computational Science and Engineering in Japan Atomic Energy Research Institute. We dealt with 14 codes in fiscal 1997. These results are reported in 3 parts, i.e., the vectorization part, the parallelization part and the porting part. In this report, we describe the vectorization. In this vectorization part, the vectorization of multidimensional two-fluid model code ACE-3D for evaluation of constitutive equations, statistical decay code SD and three-dimensional thermal analysis code for in-core test section (T2) of HENDEL SSPHEAT are described. In the parallelization part, the parallelization of cylindrical direct numerical simulation code CYLDNS44N, worldwide version of system for prediction of environmental emergency dose information code WSPEEDI, extension of quantum molecular dynamics code EQMD and three-dimensional non-steady compressible fluid dynamics code STREAM are described. In the porting part, the porting of transient reactor analysis code TRAC-BF1 and Monte Carlo radiation transport code MCNP4A on the AP3000 are described. In addition, a modification of program libraries for command-driven interactive data analysis plotting program IPLOT is described. (author)

Understanding Vector Fields.

Science.gov (United States)

Curjel, C. R.

1990-01-01

Presented are activities that help students understand the idea of a vector field. Included are definitions, flow lines, tangential and normal components along curves, flux and work, field conservation, and differential equations. (KR)

Vector hysteresis models

Czech Academy of Sciences Publication Activity Database

Krejčí, Pavel

1991-01-01

Roč. 2, - (1991), s. 281-292 ISSN 0956-7925 Keywords : vector hysteresis operator * hysteresis potential * differential inequality Subject RIV: BA - General Mathematics http://www.math.cas.cz/~krejci/b15p.pdf

ON THE ISSUE OF VECTOR CONTROL OF THE ASYNCHRONOUS MOTORS

Directory of Open Access Journals (Sweden)

B. I. Firago

2015-01-01

Full Text Available The paper considers the issue of one of the widespread types of vector control realization for the asynchronous motors with a short-circuited rotor. Of all more than 20 vector control types known presently, the following are applied most frequently: direct vector control with velocity pickup (VP, direct vector control without VP, indirect vector control with VP and indirect vector control without VP. Despite the fact that the asynchronous-motor indirect vector control without VP is the easiest and most spread, the absence of VP does not allow controlling the motor electromagnetic torque at zero velocity. This is the reason why for electric motor drives of such requirements they utilize the vector control with a velocity transducer. The systems of widest dissemination became the direct and indirect vector control systems with X-axis alignment of the synchronously rotating x–y-coordinate frame along the rotor flux-linkage vector inasmuch as this provides the simplest correlations for controlling variables. Although these two types of vector control are well presented in literature, a number of issues concerning their realization and practical application require further elaboration. These include: the block schemes adequate representation as consisted with the modern realization of vector control and clarification of the analytical expressions for evaluating the regulator parameters.The authors present a technique for evaluating the dynamics of an asynchronous electric motor drive with direct vector control and x-axis alignment along the vector of rotor flux linkage. The article offers a generalized structure of this vector control type with detailed description of its principal blocks: controlling system, frequency converter, and the asynchronous motor.The paper presents a direct vector control simulating model developed in the MatLab environment on the grounds of this structure. The authors illustrate the described technique with the results

Some remarks on a generalized vector product

OpenAIRE

ACOSTA-HUMÁNEZ, PRIMITIVO; ARANDA, MOISÉS; NÚÑEZ, REINALDO

2011-01-01

Abstract. In this paper we use a generalized vector product to construct an exterior form ⊥ : , where Finally, for n = k - 1 we introduce the reversing operation to study this generalized vector product over palindromic and antipalindromic vectors. Resumen. En este art&íacute;culo usamos un producto vectorial generalizado para construir una forma exterior ⊥ : , en donde como es natural, Finalmente, para n = k - 1 introducimos la operación reversar para estudiar este producto vectorial gene...

Virtual Vector Machine for Bayesian Online Classification

OpenAIRE

Minka, Thomas P.; Xiang, Rongjing; Yuan; Qi

2012-01-01

In a typical online learning scenario, a learner is required to process a large data stream using a small memory buffer. Such a requirement is usually in conflict with a learner's primary pursuit of prediction accuracy. To address this dilemma, we introduce a novel Bayesian online classi cation algorithm, called the Virtual Vector Machine. The virtual vector machine allows you to smoothly trade-off prediction accuracy with memory size. The virtual vector machine summarizes the information con...

Vector-Interaction-Enhanced Bag Model

Science.gov (United States)

Cierniak, Mateusz; Klähn, Thomas; Fischer, Tobias; Bastian, Niels-Uwe

2018-02-01

A commonly applied quark matter model in astrophysics is the thermodynamic bag model (tdBAG). The original MIT bag model approximates the effect of quark confinement, but does not explicitly account for the breaking of chiral symmetry, an important property of Quantum Chromodynamics (QCD). It further ignores vector repulsion. The vector-interaction-enhanced bag model (vBag) improves the tdBAG approach by accounting for both dynamical chiral symmetry breaking and repulsive vector interactions. The latter is of particular importance to studies of dense matter in beta-equilibriumto explain the two solar mass maximum mass constraint for neutron stars. The model is motivated by analyses of QCD based Dyson-Schwinger equations (DSE), assuming a simple quark-quark contact interaction. Here, we focus on the study of hybrid neutron star properties resulting from the application of vBag and will discuss possible extensions.

Search for intermediate vector bosons

International Nuclear Information System (INIS)

Cline, D.B.; Rubbia, C.; van der Meer, S.

1982-01-01

Over the past 15 years a new class of unified theories has been developed to describe the forces acting between elementary particles. The most successful of the new theories establishes a link between electromagnetism and the weak force. A crucial prediction of this unified electroweak theory is the existence of three massive particles called intermediate vector bosons. If these intermediate vector bosons exist and if they have properties attributed to them by electroweak theory, they should soon be detected, as the world's first particle accelerator with enough energy to create such particles has recently been completed at the European Organization for Nuclear Research (CERN) in Geneva. The accelerator has been converted to a colliding beam machine in which protons and antiprotons collide head on. According to electroweak theory, intermediate vector bosons can be created in proton-antiproton collisions. (SC)

Practical utilization of recombinant AAV vector reference standards: focus on vector genomes titration by free ITR qPCR

Directory of Open Access Journals (Sweden)

Susan D'Costa

2016-01-01

Full Text Available Clinical trials using recombinant adeno-associated virus (rAAV vectors have demonstrated efficacy and a good safety profile. Although the field is advancing quickly, vector analytics and harmonization of dosage units are still a limitation for commercialization. AAV reference standard materials (RSMs can help ensure product safety by controlling the consistency of assays used to characterize rAAV stocks. The most widely utilized unit of vector dosing is based on the encapsidated vector genome. Quantitative polymerase chain reaction (qPCR is now the most common method to titer vector genomes (vg; however, significant inter- and intralaboratory variations have been documented using this technique. Here, RSMs and rAAV stocks were titered on the basis of an inverted terminal repeats (ITRs sequence-specific qPCR and we found an artificial increase in vg titers using a widely utilized approach. The PCR error was introduced by using single-cut linearized plasmid as the standard curve. This bias was eliminated using plasmid standards linearized just outside the ITR region on each end to facilitate the melting of the palindromic ITR sequences during PCR. This new “Free-ITR” qPCR delivers vg titers that are consistent with titers obtained with transgene-specific qPCR and could be used to normalize in-house product-specific AAV vector standards and controls to the rAAV RSMs. The free-ITR method, including well-characterized controls, will help to calibrate doses to compare preclinical and clinical data in the field.

Practical utilization of recombinant AAV vector reference standards: focus on vector genomes titration by free ITR qPCR.

Science.gov (United States)

D'Costa, Susan; Blouin, Veronique; Broucque, Frederic; Penaud-Budloo, Magalie; François, Achille; Perez, Irene C; Le Bec, Christine; Moullier, Philippe; Snyder, Richard O; Ayuso, Eduard

2016-01-01

Clinical trials using recombinant adeno-associated virus (rAAV) vectors have demonstrated efficacy and a good safety profile. Although the field is advancing quickly, vector analytics and harmonization of dosage units are still a limitation for commercialization. AAV reference standard materials (RSMs) can help ensure product safety by controlling the consistency of assays used to characterize rAAV stocks. The most widely utilized unit of vector dosing is based on the encapsidated vector genome. Quantitative polymerase chain reaction (qPCR) is now the most common method to titer vector genomes (vg); however, significant inter- and intralaboratory variations have been documented using this technique. Here, RSMs and rAAV stocks were titered on the basis of an inverted terminal repeats (ITRs) sequence-specific qPCR and we found an artificial increase in vg titers using a widely utilized approach. The PCR error was introduced by using single-cut linearized plasmid as the standard curve. This bias was eliminated using plasmid standards linearized just outside the ITR region on each end to facilitate the melting of the palindromic ITR sequences during PCR. This new "Free-ITR" qPCR delivers vg titers that are consistent with titers obtained with transgene-specific qPCR and could be used to normalize in-house product-specific AAV vector standards and controls to the rAAV RSMs. The free-ITR method, including well-characterized controls, will help to calibrate doses to compare preclinical and clinical data in the field.

Application of Vectors to Relative Velocity

Science.gov (United States)

Tin-Lam, Toh

2004-01-01

The topic 'relative velocity' has recently been introduced into the Cambridge Ordinary Level Additional Mathematics syllabus under the application of Vectors. In this note, the results of relative velocity and the 'reduction to rest' technique of teaching relative velocity are derived mathematically from vector algebra, in the hope of providing…

Clustering Categories in Support Vector Machines

DEFF Research Database (Denmark)

Carrizosa, Emilio; Nogales-Gómez, Amaya; Morales, Dolores Romero

2017-01-01

The support vector machine (SVM) is a state-of-the-art method in supervised classification. In this paper the Cluster Support Vector Machine (CLSVM) methodology is proposed with the aim to increase the sparsity of the SVM classifier in the presence of categorical features, leading to a gain in in...

A design of a computer complex including vector processors

International Nuclear Information System (INIS)

Asai, Kiyoshi

1982-12-01

We, members of the Computing Center, Japan Atomic Energy Research Institute have been engaged for these six years in the research of adaptability of vector processing to large-scale nuclear codes. The research has been done in collaboration with researchers and engineers of JAERI and a computer manufacturer. In this research, forty large-scale nuclear codes were investigated from the viewpoint of vectorization. Among them, twenty-six codes were actually vectorized and executed. As the results of the investigation, it is now estimated that about seventy percents of nuclear codes and seventy percents of our total amount of CPU time of JAERI are highly vectorizable. Based on the data obtained by the investigation, (1)currently vectorizable CPU time, (2)necessary number of vector processors, (3)necessary manpower for vectorization of nuclear codes, (4)computing speed, memory size, number of parallel 1/0 paths, size and speed of 1/0 buffer of vector processor suitable for our applications, (5)necessary software and operational policy for use of vector processors are discussed, and finally (6)a computer complex including vector processors is presented in this report. (author)

Bearing estimation with acoustic vector-sensor arrays

International Nuclear Information System (INIS)

Hawkes, M.; Nehorai, A.

1996-01-01

We consider direction-of-arrival (DOA) estimation using arrays of acoustic vector sensors in free space, and derive expressions for the Cramacute er-Rao bound on the DOA parameters when there is a single source. The vector-sensor array is seen to have improved performance over the traditional scalar-sensor (pressure-sensor) array for two distinct reasons: its elements have an inherent directional sensitivity and the array makes a greater number of measurements. The improvement is greatest for small array apertures and low signal-to-noise ratios. Examination of the conventional beamforming and Capon DOA estimators shows that vector-sensor arrays can completely resolve the bearing, even with a linear array, and can remove the ambiguities associated with spatial undersampling. We also propose and analyze a diversely-oriented array of velocity sensors that possesses some of the advantages of the vector-sensor array without the increase in hardware and computation. In addition, in certain scenarios it can avoid problems with spatially correlated noise that the vector-sensor array may suffer. copyright 1996 American Institute of Physics

Vectoring of parallel synthetic jets: A parametric study

Science.gov (United States)

Berk, Tim; Gomit, Guillaume; Ganapathisubramani, Bharathram

2016-11-01

The vectoring of a pair of parallel synthetic jets can be described using five dimensionless parameters: the aspect ratio of the slots, the Strouhal number, the Reynolds number, the phase difference between the jets and the spacing between the slots. In the present study, the influence of the latter four on the vectoring behaviour of the jets is examined experimentally using particle image velocimetry. Time-averaged velocity maps are used to study the variations in vectoring behaviour for a parametric sweep of each of the four parameters independently. A topological map is constructed for the full four-dimensional parameter space. The vectoring behaviour is described both qualitatively and quantitatively. A vectoring mechanism is proposed, based on measured vortex positions. We acknowledge the financial support from the European Research Council (ERC Grant Agreement No. 277472).

Line Width Recovery after Vectorization of Engineering Drawings

Directory of Open Access Journals (Sweden)

Gramblička Matúš

2016-12-01

Full Text Available Vectorization is the conversion process of a raster image representation into a vector representation. The contemporary commercial vectorization software applications do not provide sufficiently high quality outputs for such images as do mechanical engineering drawings. Line width preservation is one of the problems. There are applications which need to know the line width after vectorization because this line attribute carries the important semantic information for the next 3D model generation. This article describes the algorithm that is able to recover line width of individual lines in the vectorized engineering drawings. Two approaches are proposed, one examines the line width at three points, whereas the second uses a variable number of points depending on the line length. The algorithm is tested on real mechanical engineering drawings.

Vector-transmitted disease vaccines: targeting salivary proteins in transmission (SPIT).

Science.gov (United States)

McDowell, Mary Ann

2015-08-01

More than half the population of the world is at risk for morbidity and mortality from vector-transmitted diseases, and emerging vector-transmitted infections are threatening new populations. Rising insecticide resistance and lack of efficacious vaccines highlight the need for novel control measures. One such approach is targeting the vector-host interface by incorporating vector salivary proteins in anti-pathogen vaccines. Debate remains about whether vector saliva exposure exacerbates or protects against more severe clinical manifestations, induces immunity through natural exposure or extends to all vector species and associated pathogens. Nevertheless, exploiting this unique biology holds promise as a viable strategy for the development of vaccines against vector-transmitted diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lentiviral Vector Gene Transfer to Porcine Airways

Directory of Open Access Journals (Sweden)

Patrick L Sinn

2012-01-01

Full Text Available In this study, we investigated lentiviral vector development and transduction efficiencies in well-differentiated primary cultures of pig airway epithelia (PAE and wild-type pigs in vivo. We noted gene transfer efficiencies similar to that observed for human airway epithelia (HAE. Interestingly, feline immunodeficiency virus (FIV-based vectors transduced immortalized pig cells as well as pig primary cells more efficiently than HIV-1–based vectors. PAE express TRIM5α, a well-characterized species-specific lentiviral restriction factor. We contrasted the restrictive properties of porcine TRIM5α against FIV- and HIV-based vectors using gain and loss of function approaches. We observed no effect on HIV-1 or FIV conferred transgene expression in response to porcine TRIM5α overexpression or knockdown. To evaluate the ability of GP64-FIV to transduce porcine airways in vivo, we delivered vector expressing mCherry to the tracheal lobe of the lung and the ethmoid sinus of 4-week-old pigs. One week later, epithelial cells expressing mCherry were readily detected. Our findings indicate that pseudotyped FIV vectors confer similar tropisms in porcine epithelia as observed in human HAE and provide further support for the selection of GP64 as an appropriate envelope pseudotype for future preclinical gene therapy studies in the porcine model of cystic fibrosis (CF.

RNA Interference in Insect Vectors for Plant Viruses

Directory of Open Access Journals (Sweden)

Surapathrudu Kanakala

2016-12-01

Full Text Available Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi was recently suggested as a promising strategy for controlling insect pests, including those that serve as important vectors for plant pathogens. The last decade has witnessed a dramatic increase in the functional analysis of insect genes, especially those whose silencing results in mortality or interference with pathogen transmission. The identification of such candidates poses a major challenge for increasing the role of RNAi in pest control. Another challenge is to understand the RNAi machinery in insect cells and whether components that were identified in other organisms are also present in insect. This review will focus on summarizing success cases in which RNAi was used for silencing genes in insect vector for plant pathogens, and will be particularly helpful for vector biologists.

Current vector control challenges in the fight against malaria.

Science.gov (United States)

Benelli, Giovanni; Beier, John C

2017-10-01

The effective and eco-friendly control of Anopheles vectors plays a key role in any malaria management program. Integrated Vector Management (IVM) suggests making use of the full range of vector control tools available. The strategies for IVM require novel technologies to control outdoor transmission of malaria. Despite the wide number of promising control tools tested against mosquitoes, current strategies for malaria vector control used in most African countries are not sufficient to achieve successful malaria control. The majority of National Malaria Control Programs in Africa still rely on indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). These methods reduce malaria incidence but generally have little impact on malaria prevalence. In addition to outdoor transmission, growing levels of insecticide resistance in targeted vectors threaten the efficacy of LLINs and IRS. Larvicidal treatments can be useful, but are not recommended for rural areas. The research needed to improve the quality and delivery of mosquito vector control should focus on (i) optimization of processes and methods for vector control delivery; (ii) monitoring of vector populations and biting activity with reliable techniques; (iii) the development of effective and eco-friendly tools to reduce the burden or locally eliminate malaria and other mosquito-borne diseases; (iv) the careful evaluation of field suitability and efficacy of new mosquito control tools to prove their epidemiological impact; (v) the continuous monitoring of environmental changes which potentially affect malaria vector populations; (vi) the cooperation among different disciplines, with main emphasis on parasitology, tropical medicine, ecology, entomology, and ecotoxicology. A better understanding of behavioral ecology of malaria vectors is required. Key ecological obstacles that limit the effectiveness of vector control include the variation in mosquito behavior, development of insecticide resistance

Vector pulsing soliton of self-induced transparency in waveguide

International Nuclear Information System (INIS)

Adamashvili, G.T.

2015-01-01

A theory of an optical resonance vector pulsing soliton in waveguide is developed. A thin transition layer containing semiconductor quantum dots forms the boundary between the waveguide and one of the connected media. Analytical and numerical solutions for the optical vector pulsing soliton in waveguide are obtained. The vector pulsing soliton in the presence of excitonic and bi-excitonic excitations is compared with the soliton for waveguide TM-modes with parameters that can be used in modern optical experiments. It is shown that these nonlinear waves have significantly different parameters and shapes. - Highlights: • An optical vector pulsing soliton in a planar waveguide is presented. • Explicit form of the optical vector pulsing soliton are obtained. • The vector pulsing soliton and the soliton have different parameters and profiles

Interior point decoding for linear vector channels

International Nuclear Information System (INIS)

Wadayama, T

2008-01-01

In this paper, a novel decoding algorithm for low-density parity-check (LDPC) codes based on convex optimization is presented. The decoding algorithm, called interior point decoding, is designed for linear vector channels. The linear vector channels include many practically important channels such as inter-symbol interference channels and partial response channels. It is shown that the maximum likelihood decoding (MLD) rule for a linear vector channel can be relaxed to a convex optimization problem, which is called a relaxed MLD problem

Interior point decoding for linear vector channels

Energy Technology Data Exchange (ETDEWEB)

Wadayama, T [Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya, Aichi, 466-8555 (Japan)], E-mail: wadayama@nitech.ac.jp

2008-01-15

In this paper, a novel decoding algorithm for low-density parity-check (LDPC) codes based on convex optimization is presented. The decoding algorithm, called interior point decoding, is designed for linear vector channels. The linear vector channels include many practically important channels such as inter-symbol interference channels and partial response channels. It is shown that the maximum likelihood decoding (MLD) rule for a linear vector channel can be relaxed to a convex optimization problem, which is called a relaxed MLD problem.

Characterizing Compromise Stability of Games Using Larginal Vectors

NARCIS (Netherlands)

Platz, T.T.; Hamers, H.J.M.; Quant, M.

2011-01-01

The core cover of a TU-game is a superset of the core and equals the convex hull of its larginal vectors. A larginal vector corresponds to an order of the players and describes the efficient payoff vector giving the first players in the order their utopia demand as long as it is still possible to

Measurements of the n vector p vector total cross section differences for pure helicity states at 1.20, 2.50 and 3.66 GeV

International Nuclear Information System (INIS)

Sharov, V.I.; Zaporozhets, S.A.; Ad''yasevich, B.P.

1996-01-01

The quantity Δσ L (n vector p vector), the difference of n vector p vector total cross sections for antiparallel and parallel longitudinal (L) spin states, has been measured for the first time in an energy region of several GeV using a free polarized neutron beam and a polarized proton target. The new data are discussed together with existing results and modern theoretical predictions. This is the first of a planned series of measurements of Δσ L,T (n vector p vector) in this new energy region. 28 refs., 3 figs

Viruses vector control proposal: genus Aedes emphasis

Directory of Open Access Journals (Sweden)

Nelson Nogueira Reis

2017-07-01

Full Text Available The dengue fever is a major public health problem in the world. In Brazil, in 2015, there were 1,534,932 cases, being 20,320 cases of severe form, and 811 deaths related to this disease. The distribution of Aedes aegypti, the vector, is extensive. Recently, Zika and Chikungunya viruses had arisen, sharing the same vector as dengue and became a huge public health issue. Without specific treatment, it is urgently required as an effective vector control. This article is focused on reviewing vector control strategies, their effectiveness, viability and economical impact. Among all, the Sterile Insect Technique is highlighted as the best option to be adopted in Brazil, once it is largely effectively used in the USA and Mexico for plagues related to agribusiness.

Comparison Between Several Integrase-defective Lentiviral Vectors Reveals Increased Integration of an HIV Vector Bearing a D167H Mutant

Directory of Open Access Journals (Sweden)

Muhammad Qamar Saeed

2014-01-01

Full Text Available HIV-1 derived vectors are among the most efficient for gene transduction in mammalian tissues. As the parent virus, they carry out vector genome insertion into the host cell chromatin. Consequently, their preferential integration in transcribed genes raises several conceptual and safety issues. To address part of these questions, HIV-derived vectors have been engineered to be nonintegrating. This was mainly achieved by mutating HIV-1 integrase at functional hotspots of the enzyme enabling the development of streamlined nuclear DNA circles functional for transgene expression. Few integrase mutant vectors have been successfully tested so far for gene transfer. They are cleared with time in mitotic cells, but stable within nondividing retina cells or neurons. Here, we compared six HIV vectors carrying different integrases, either wild type or with different mutations (D64V, D167H, Q168A, K186Q+Q214L+Q216L, and RRK262-264AAH shown to modify integrase enzymatic activity, oligomerization, or interaction with key cellular cofactor of HIV DNA integration as LEDGF/p75 or TNPO3. We show that these mutations differently affect the transduction efficiency as well as rates and patterns of integration of HIV-derived vectors suggesting their different processing in the nucleus. Surprisingly and most interestingly, we report that an integrase carrying the D167H substitution improves vector transduction efficiency and integration in both HEK-293T and primary CD34+ cells.

Search for vector-like quarks

CERN Document Server

Varnes, Erich; The ATLAS collaboration

2017-01-01

Vector like quarks appear in many theories beyond the Standard Model as a way to cancel the mass divergence for the Higgs boson. The current status of the ATLAS searches for the production of vector like quarks will be reviewed for proton-proton collisions at 13 TeV. This presentation will address the analysis techniques, in particular the selection criteria, the background modeling and the related experimental uncertainties. The phenomenological implications of the obtained results will also be discussed.

Zoonotic aspects of vector-borne infections.

Science.gov (United States)

Failloux, A-B; Moutailler, S

2015-04-01

Vector-borne diseases are principally zoonotic diseases transmitted to humans by animals. Pathogens such as bacteria, parasites and viruses are primarily maintained within an enzootic cycle between populations of non-human primates or other mammals and largely non-anthropophilic vectors. This 'wild' cycle sometimes spills over in the form of occasional infections of humans and domestic animals. Lifestyle changes, incursions by humans into natural habitats and changes in agropastoral practices create opportunities that make the borders between wildlife and humans more permeable. Some vector-borne diseases have dispensed with the need for amplification in wild or domestic animals and they can now be directly transmitted to humans. This applies to some viruses (dengue and chikungunya) that have caused major epidemics. Bacteria of the genus Bartonella have reduced their transmission cycle to the minimum, with humans acting as reservoir, amplifier and disseminator. The design of control strategies for vector-borne diseases should be guided by research into emergence mechanisms in order to understand how a wild cycle can produce a pathogen that goes on to cause devastating urban epidemics.

Attenuation of Replication-Competent Adenovirus Serotype 26 Vaccines by Vectorization.

Science.gov (United States)

Maxfield, Lori F; Abbink, Peter; Stephenson, Kathryn E; Borducchi, Erica N; Ng'ang'a, David; Kirilova, Marinela M; Paulino, Noelix; Boyd, Michael; Shabram, Paul; Ruan, Qian; Patel, Mayank; Barouch, Dan H

2015-11-01

Replication-competent adenovirus (rcAd)-based vaccine vectors may theoretically provide immunological advantages over replication-incompetent Ad vectors, but they also raise additional potential clinical and regulatory issues. We produced replication-competent Ad serotype 26 (rcAd26) vectors by adding the E1 region back into a replication-incompetent Ad26 vector backbone with the E3 or E3/E4 regions deleted. We assessed the effect of vectorization on the replicative capacity of the rcAd26 vaccines. Attenuation occurred in a stepwise fashion, with E3 deletion, E4 deletion, and human immunodeficiency virus type 1 (HIV-1) envelope (Env) gene insertion all contributing to reduced replicative capacity compared to that with the wild-type Ad26 vector. The rcAd26 vector with E3 and E4 deleted and containing the Env transgene exhibited 2.7- to 4.4-log-lower replicative capacity than that of the wild-type Ad26 in vitro. This rcAd26 vector is currently being evaluated in a phase 1 clinical trial. Attenuation as a result of vectorization and transgene insertion has implications for the clinical development of replication-competent vaccine vectors. Copyright © 2015, Maxfield et al.

Interactions between parasites and insects vectors

Directory of Open Access Journals (Sweden)

Hilary Hurd

1994-01-01

Full Text Available This review stresses the importance of studies that will provide a basic understanding of the pathology of parasite-infected vector insects. This knowledge should be a vital component of the very focussed initiatives currently being funded in the areas of vector control. Vector fecundity reduction is discussed as an example of such pathology. Underlying mechanisms are being investigated in a model system, Hymenolepis diminuta-infected Tenebrio molitor and in Onchocerca-infected blackflies and Plasmodium-infected Anopheles stephensi. In all cases, host vitellogenesis is disrupted by the parasite and, in the tapeworm/beetle model, interaction between the parasite and the endocrine control of the insect's reproductive physiology has been demonstrated.

The optical analogy for vector fields

Science.gov (United States)

Parker, E. N. (Editor)

1991-01-01

This paper develops the optical analogy for a general vector field. The optical analogy allows the examination of certain aspects of a vector field that are not otherwise readily accessible. In particular, in the cases of a stationary Eulerian flow v of an ideal fluid and a magnetostatic field B, the vectors v and B have surface loci in common with their curls. The intrinsic discontinuities around local maxima in absolute values of v and B take the form of vortex sheets and current sheets, respectively, the former playing a fundamental role in the development of hydrodyamic turbulence and the latter playing a major role in heating the X-ray coronas of stars and galaxies.

Circumventing antivector immunity: potential use of nonhuman adenoviral vectors.

Science.gov (United States)

Lopez-Gordo, Estrella; Podgorski, Iva I; Downes, Nicholas; Alemany, Ramon

2014-04-01

Adenoviruses are efficient gene delivery vectors based on their ability to transduce a wide variety of cell types and drive high-level transient transgene expression. While there have been advances in modifying human adenoviral (HAdV) vectors to increase their safety profile, there are still pitfalls that need to be further addressed. Preexisting humoral and cellular immunity against common HAdV serotypes limits the efficacy of gene transfer and duration of transgene expression. As an alternative, nonhuman AdV (NHAdV) vectors can circumvent neutralizing antibodies against HAdVs in immunized mice and monkeys and in human sera, suggesting that NHAdV vectors could circumvent preexisting humoral immunity against HAdVs in a clinical setting. Consequently, there has been an increased interest in developing NHAdV vectors for gene delivery in humans. In this review, we outline the recent advances and limitations of HAdV vectors for gene therapy and describe examples of NHAdV vectors focusing on their immunogenicity, tropism, and potential as effective gene therapy vehicles.

Method of dynamic fuzzy symptom vector in intelligent diagnosis

International Nuclear Information System (INIS)

Sun Hongyan; Jiang Xuefeng

2010-01-01

Aiming at the requirement of diagnostic symptom real-time updating brought from diagnostic knowledge accumulation and great gap in unit and value of diagnostic symptom in multi parameters intelligent diagnosis, the method of dynamic fuzzy symptom vector is proposed. The concept of dynamic fuzzy symptom vector is defined. Ontology is used to specify the vector elements, and the vector transmission method based on ontology is built. The changing law of symptom value is analyzed and fuzzy normalization method based on fuzzy membership functions is built. An instance proved method of dynamic fussy symptom vector is efficient to solve the problems of symptom updating and unify of symptom value and unit. (authors)

Logarithmic bred vectors in spatiotemporal chaos: structure and growth.

Science.gov (United States)

Hallerberg, Sarah; Pazó, Diego; López, Juan M; Rodríguez, Miguel A

2010-06-01

Bred vectors are a type of finite perturbation used in prediction studies of atmospheric models that exhibit spatially extended chaos. We study the structure, spatial correlations, and the growth rates of logarithmic bred vectors (which are constructed by using a given norm). We find that, after a suitable transformation, logarithmic bred vectors are roughly piecewise copies of the leading Lyapunov vector. This fact allows us to deduce a scaling law for the bred vector growth rate as a function of its amplitude. In addition, we relate growth rates with the spectrum of Lyapunov exponents corresponding to the most expanding directions. We illustrate our results with simulations of the Lorenz 1996 model.

Topics in the generalized vector dominance model

International Nuclear Information System (INIS)

Chavin, S.

1976-01-01

Two topics are covered in the generalized vector dominance model. In the first topic a model is constructed for dilepton production in hadron-hadron interactions based on the idea of generalized vector-dominance. It is argued that in the high mass region the generalized vector-dominance model and the Drell-Yan parton model are alternative descriptions of the same underlying physics. In the low mass regions the models differ; the vector-dominance approach predicts a greater production of dileptons. It is found that the high mass vector mesons which are the hallmark of the generalized vector-dominance model make little contribution to the large yield of leptons observed in the transverse-momentum range 1 less than p/sub perpendicular/ less than 6 GeV. The recently measured hadronic parameters lead one to believe that detailed fits to the data are possible under the model. The possibility was expected, and illustrated with a simple model the extreme sensitivity of the large-p/sub perpendicular/ lepton yield to the large-transverse-momentum tail of vector-meson production. The second topic is an attempt to explain the mysterious phenomenon of photon shadowing in nuclei utilizing the contribution of the longitudinally polarized photon. It is argued that if the scalar photon anti-shadows, it could compensate for the transverse photon, which is presumed to shadow. It is found in a very simple model that the scalar photon could indeed anti-shadow. The principal feature of the model is a cancellation of amplitudes. The scheme is consistent with scalar photon-nucleon data as well. The idea is tested with two simple GVDM models and finds that the anti-shadowing contribution of the scalar photon is not sufficient to compensate for the contribution of the transverse photon. It is found doubtful that the scalar photon makes a significant contribution to the total photon-nuclear cross section

Observability of B0 - B vector0 mixing in the e+e- → BB vector X reaction at √s approx. = 15 - 30 GeV

International Nuclear Information System (INIS)

Fridman, A.; Schwarz, A.

1985-01-01

The possibility of observing mixing in the B 0 B vector B 0 system has been rather widely discussed. In particular theoretical estimates have been made for the case of B 0 B vector 0 production in the e + e - → upsilon (4S) → B 0 B vector 0 reaction. Mixing in this specific channel is expected to appear as a small effect and might thus be hardly measurable. Here the authors will therefore consider the e + e - → BB vector X reaction (X meaning anything well above the BB vector threshold where any combination of BB vector mesons (B/sub u/B vector/sub u/, B/sub u/B vector/sub d/, B/sub u/B vector/sub s/, etc.) can be produced. This reaction might be advantageous as mixing is expected to be almost complete for the B/sub s/ mesons. In this respect the study of mixing effects in the e + e - → BB vector X reaction is complementary to that in the e + e - → upsilon (4S) → B/sub d/ 0 B vector /sub e/ 0 process. In Section B.2 the authors recall briefly the parameters used to describe the BB vector mixing and in Section B.3 they give estimates for the mixing effects which could be observed in the e + e - → BB vector X reaction as well as in the upsilon (4S) decays. The authors have also evaluated the influence of a non-spectator component in the B-decay on the observability of the mixing phenomenon. Finally, in Section B.4 they give estimates for the number of signal and background events which could be observed in an e + e - experiment with an accumulated luminosity of 1000 pb -1 . 33 references, 4 figures

Improved Coinfection with Amphotropic Pseudotyped Retroviral Vectors

Directory of Open Access Journals (Sweden)

Yuehong Wu

2009-01-01

Full Text Available Amphotropic pseudotyped retroviral vectors have typically been used to infect target cells without prior concentration. Although this can yield high rates of infection, higher rates may be needed where highly efficient coinfection of two or more vectors is needed. In this investigation we used amphotropic retroviral vectors produced by the Plat-A cell line and studied coinfection rates using green and red fluorescent proteins (EGFP and dsRed2. Target cells were primary human fibroblasts (PHF and 3T3 cells. Unconcentrated vector preparations produced a coinfection rate of ∼4% (defined as cells that are both red and green as a percentage of all cells infected. Optimized spinoculation, comprising centrifugation at 1200 g for 2 hours at 15∘C, increased the coinfection rate to ∼10%. Concentration by centrifugation at 10,000 g or by flocculation using Polybrene increased the coinfection rate to ∼25%. Combining the two processes, concentration by Polybrene flocculation and optimized spinoculation, increased the coinfection rate to 35% (3T3 or >50% (PHF. Improved coinfection should be valuable in protocols that require high transduction by combinations of two or more retroviral vectors.

Virus infection of a weed increases vector attraction to and vector fitness on the weed.

Science.gov (United States)

Chen, Gong; Pan, Huipeng; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Fang, Yong; Shi, Xiaobin; Zhang, Youjun

2013-01-01

Weeds are important in the ecology of field crops, and when crops are harvested, weeds often become the main hosts for plant viruses and their insect vectors. Few studies, however, have examined the relationships between plant viruses, vectors, and weeds. Here, we investigated how infection of the weed Datura stramonium L. by tomato yellow leaf curl virus (TYLCV) affects the host preference and performance of the TYLCV vector, Bemisia tabaci (Gennadius) Q. The results of a choice experiment indicated that B. tabaci Q preferentially settled and oviposited on TYLCV-infected plants rather than on healthy plants. In addition, B. tabaci Q performed better on TYLCV-infected plants than on healthy plants. These results demonstrate that TYLCV is indirectly mutualistic to B. tabaci Q. The mutually beneficial interaction between TYLCV and B. tabaci Q may help explain the concurrent outbreaks of TYLCV and B. tabaci Q in China.

Controllability of linear vector fields on Lie groups

International Nuclear Information System (INIS)

Ayala, V.; Tirao, J.

1994-11-01

In this paper, we shall deal with a linear control system Σ defined on a Lie group G with Lie algebra g. The dynamic of Σ is determined by the drift vector field which is an element in the normalizer of g in the Lie algebra of all smooth vector field on G and by the control vectors which are elements in g considered as left-invariant vector fields. We characterize the normalizer of g identifying vector fields on G with C ∞ -functions defined on G into g. For this class of control systems we study algebraic conditions for the controllability problem. Indeed, we prove that if the drift vector field has a singularity then the Lie algebra rank condition is necessary for the controllability property, but in general this condition does not determine this property. On the other hand, we show that the rank (ad-rank) condition is sufficient for the controllability of Σ. In particular, we extend the fundamental Kalman's theorem when G is an Abelian connected Lie group. Our work is related with a paper of L. Markus and we also improve his results. (author). 7 refs

Neuron-specific RNA interference using lentiviral vectors

DEFF Research Database (Denmark)

Nielsen, Troels Tolstrup; Marion, Ingrid van; Hasholt, Lis

2009-01-01

BACKGROUND: Viral vectors have been used in several different settings for the delivery of small hairpin (sh) RNAs. However, most vectors have utilized ubiquitously-expressing polymerase (pol) III promoters to drive expression of the hairpin as a result of the strict requirement for precise...... transcriptional initiation and termination. Recently, pol II promoters have been used to construct vectors for RNA interference (RNAi). By embedding the shRNA into a micro RNA-context (miRNA) the endogenous miRNA processing machinery is exploited to achieve the mature synthetic miRNA (smiRNA), thereby expanding...... the possible promoter choices and eventually allowing cell type specific down-regulation of target genes. METHODS: In the present study, we constructed lentiviral vectors expressing smiRNAs under the control of pol II promoters to knockdown gene expression in cell culture and in the brain. RESULTS: We...

VEST: Abstract vector calculus simplification in Mathematica

Science.gov (United States)

Squire, J.; Burby, J.; Qin, H.

2014-01-01

We present a new package, VEST (Vector Einstein Summation Tools), that performs abstract vector calculus computations in Mathematica. Through the use of index notation, VEST is able to reduce three-dimensional scalar and vector expressions of a very general type to a well defined standard form. In addition, utilizing properties of the Levi-Civita symbol, the program can derive types of multi-term vector identities that are not recognized by reduction, subsequently applying these to simplify large expressions. In a companion paper Burby et al. (2013) [12], we employ VEST in the automation of the calculation of high-order Lagrangians for the single particle guiding center system in plasma physics, a computation which illustrates its ability to handle very large expressions. VEST has been designed to be simple and intuitive to use, both for basic checking of work and more involved computations.

Weaving Knotted Vector Fields with Tunable Helicity.

Science.gov (United States)

Kedia, Hridesh; Foster, David; Dennis, Mark R; Irvine, William T M

2016-12-30

We present a general construction of divergence-free knotted vector fields from complex scalar fields, whose closed field lines encode many kinds of knots and links, including torus knots, their cables, the figure-8 knot, and its generalizations. As finite-energy physical fields, they represent initial states for fields such as the magnetic field in a plasma, or the vorticity field in a fluid. We give a systematic procedure for calculating the vector potential, starting from complex scalar functions with knotted zero filaments, thus enabling an explicit computation of the helicity of these knotted fields. The construction can be used to generate isolated knotted flux tubes, filled by knots encoded in the lines of the vector field. Lastly, we give examples of manifestly knotted vector fields with vanishing helicity. Our results provide building blocks for analytical models and simulations alike.

The evolution of heart gene delivery vectors

Science.gov (United States)

Wasala, Nalinda B.; Shin, Jin-Hong; Duan, Dongsheng

2012-01-01

Gene therapy holds promise for treating numerous heart diseases. A key premise for the success of cardiac gene therapy is the development of powerful gene transfer vehicles that can achieve highly efficient and persistent gene transfer specifically in the heart. Other features of an ideal vector include negligible toxicity, minimal immunogenicity and easy manufacturing. Rapid progress in the fields of molecular biology and virology has offered great opportunities to engineer various genetic materials for heart gene delivery. Several nonviral vectors (e.g. naked plasmids, plasmid lipid/polymer complexes and oligonucleotides) have been tested. Commonly used viral vectors include lentivirus, adenovirus and adeno-associated virus. Among these, adeno-associated virus has shown many attractive features for pre-clinical experimentation in animal models of heart diseases. We review the history and evolution of these vectors for heart gene transfer. PMID:21837689

Techniques for vector analyzing power measurements of the 2H(n vector,np)n breakup reaction at low energies

International Nuclear Information System (INIS)

Howell, C.R.; Tornow, W.; Pfuetzner, H.G.; Li Anli; Roberts, M.L.; Murphy, K.; Felsher, P.D.; Weisel, G.J.; Naqvi, A.; Walter, R.L.; Lambert, J.M.; Treado, P.A.

1990-01-01

Experimental methods to measure the vector analyzing powers over a broad range of kinematic configurations in the n-d breakup reaction have been developed at TUNL. These techniques employ the polarized beam facilities at TUNL and use the 2 H(d vector, n vector) 3 He reaction as a source of low-energy polarized neutrons. Our methods permit measurements to a high statistical accuracy over a large fraction of three-nucleon phase space. The techniques are described and experimental spectra along with kinematic calculations are presented. (orig.)

Data-driven identification of potential Zika virus vectors

Science.gov (United States)

Evans, Michelle V; Dallas, Tad A; Han, Barbara A; Murdock, Courtney C; Drake, John M

2017-01-01

Zika is an emerging virus whose rapid spread is of great public health concern. Knowledge about transmission remains incomplete, especially concerning potential transmission in geographic areas in which it has not yet been introduced. To identify unknown vectors of Zika, we developed a data-driven model linking vector species and the Zika virus via vector-virus trait combinations that confer a propensity toward associations in an ecological network connecting flaviviruses and their mosquito vectors. Our model predicts that thirty-five species may be able to transmit the virus, seven of which are found in the continental United States, including Culex quinquefasciatus and Cx. pipiens. We suggest that empirical studies prioritize these species to confirm predictions of vector competence, enabling the correct identification of populations at risk for transmission within the United States. DOI: http://dx.doi.org/10.7554/eLife.22053.001 PMID:28244371

An exotic composite vector boson

International Nuclear Information System (INIS)

Akama, Keiichi; Hattori, Takashi; Yasue, Masaki.

1990-08-01

An exotic composite vector boson, V, is introduced in two dynamical models of composite quarks, leptons, W and Z. One is based on four Fermi interactions, in which composite vector bosons are regarded as fermion-antifermion bound states and the other is based on the confining SU(2) L gauge model, in which they are given by scalar-antiscalar bound states. Both approaches describe the same effective interactions for the sector of composite quarks, leptons, W, Z, γ and V. (author)

Vector mesons and chiral symmetry

International Nuclear Information System (INIS)

Ecker, G.

1989-01-01

The ambiguities in the off-shell behaviour of spin-1 exchange can be resolved to O(p 4 ) in the chiral low-energy expansion if the asymptotic behaviour of QCD is properly incorporated. As a consequence, the chiral version of vector (and axial-vector) meson dominance is model independent. Additional high-energy constraints motivated by QCD determine the V,A resonance couplings uniquely. In particular, QCD in its effective chiral realization sucessfully predicts Γ(ρ→2π). 10 refs. (Author)

Vector Boolean Functions: applications in symmetric cryptography

OpenAIRE

Álvarez Cubero, José Antonio

2015-01-01

Esta tesis establece los fundamentos teóricos y diseña una colección abierta de clases C++ denominada VBF (Vector Boolean Functions) para analizar funciones booleanas vectoriales (funciones que asocian un vector booleano a otro vector booleano) desde una perspectiva criptográfica. Esta nueva implementación emplea la librería NTL de Victor Shoup, incorporando nuevos módulos que complementan a las funciones de NTL, adecuándolas para el análisis criptográfico. La clase fundamental que representa...

Vector analysis for mathematicians, scientists and engineers

CERN Document Server

Simons, S

1970-01-01

Vector Analysis for Mathematicians, Scientists and Engineers, Second Edition, provides an understanding of the methods of vector algebra and calculus to the extent that the student will readily follow those works which make use of them, and further, will be able to employ them himself in his own branch of science. New concepts and methods introduced are illustrated by examples drawn from fields with which the student is familiar, and a large number of both worked and unworked exercises are provided. The book begins with an introduction to vectors, covering their representation, addition, geome

Can really the electromagnetic transverse waves with E-vector parallel to B-vector and finite energy exist?

International Nuclear Information System (INIS)

Malinowski, S.

1984-01-01

It is shown that the total field energy for general solutions of the sourceless Maxwell's equations with E-vector parallel to B-vector is infinite. Moreover the action and/or the ''pseudoscalar charge'' must be infinite too in this case. Therefore the expected similarity to the instanton or meron solutions of nonabelian gauge theories is illusory. 5 refs. (author)

Gauge Theories of Vector Particles

Science.gov (United States)

Glashow, S. L.; Gell-Mann, M.

1961-04-24

The possibility of generalizing the Yang-Mills trick is examined. Thus we seek theories of vector bosons invariant under continuous groups of coordinate-dependent linear transformations. All such theories may be expressed as superpositions of certain "simple" theories; we show that each "simple theory is associated with a simple Lie algebra. We may introduce mass terms for the vector bosons at the price of destroying the gauge-invariance for coordinate-dependent gauge functions. The theories corresponding to three particular simple Lie algebras - those which admit precisely two commuting quantum numbers - are examined in some detail as examples. One of them might play a role in the physics of the strong interactions if there is an underlying super-symmetry, transcending charge independence, that is badly broken. The intermediate vector boson theory of weak interactions is discussed also. The so-called "schizon" model cannot be made to conform to the requirements of partial gauge-invariance.

Toward lattice fractional vector calculus

International Nuclear Information System (INIS)

Tarasov, Vasily E

2014-01-01

An analog of fractional vector calculus for physical lattice models is suggested. We use an approach based on the models of three-dimensional lattices with long-range inter-particle interactions. The lattice analogs of fractional partial derivatives are represented by kernels of lattice long-range interactions, where the Fourier series transformations of these kernels have a power-law form with respect to wave vector components. In the continuum limit, these lattice partial derivatives give derivatives of non-integer order with respect to coordinates. In the three-dimensional description of the non-local continuum, the fractional differential operators have the form of fractional partial derivatives of the Riesz type. As examples of the applications of the suggested lattice fractional vector calculus, we give lattice models with long-range interactions for the fractional Maxwell equations of non-local continuous media and for the fractional generalization of the Mindlin and Aifantis continuum models of gradient elasticity. (papers)

Toward lattice fractional vector calculus

Science.gov (United States)

Tarasov, Vasily E.

2014-09-01

An analog of fractional vector calculus for physical lattice models is suggested. We use an approach based on the models of three-dimensional lattices with long-range inter-particle interactions. The lattice analogs of fractional partial derivatives are represented by kernels of lattice long-range interactions, where the Fourier series transformations of these kernels have a power-law form with respect to wave vector components. In the continuum limit, these lattice partial derivatives give derivatives of non-integer order with respect to coordinates. In the three-dimensional description of the non-local continuum, the fractional differential operators have the form of fractional partial derivatives of the Riesz type. As examples of the applications of the suggested lattice fractional vector calculus, we give lattice models with long-range interactions for the fractional Maxwell equations of non-local continuous media and for the fractional generalization of the Mindlin and Aifantis continuum models of gradient elasticity.

Study of The Vector Product using Three Dimensions Vector Card of Engineering in Pathumwan Institute of Technology

Science.gov (United States)

Mueanploy, Wannapa

2015-06-01

The objective of this research was to offer the way to improve engineering students in Physics topic of vector product. The sampling of this research was the engineering students at Pathumwan Institute of Technology during the first semester of academic year 2013. 1) Select 120 students by random sampling are asked to fill in a satisfaction questionnaire scale, to select size of three dimensions vector card in order to apply in the classroom. 2) Select 60 students by random sampling to do achievement test and take the test to be used in the classroom. The methods used in analysis of achievement test by the Kuder-Richardson Method (KR- 20). The results show that 12 items of achievement test are appropriate to be applied in the classroom. The achievement test gets Difficulty (P) = 0.40-0.67, Discrimination = 0.33-0.73 and Reliability (r) = 0.70.The experimental in the classroom. 3) Select 60 students by random sampling divide into two groups; group one (the controlled group) with 30 students was chosen to study in the vector product lesson by the regular teaching method. Group two (the experimental group) with 30 students was chosen to learn the vector product lesson with three dimensions vector card. 4) Analyzed data between the controlled group and the experimental group, the result showed that experimental group got higher achievement test than the controlled group significant at .01 level.

Nonperturbative Aspects of Axial Vector Vertex

Institute of Scientific and Technical Information of China (English)

ZONG Hong-Shi; CHEN Xiang-Song; WANG Fan; CHANG Chao-Hsi; ZHAO En-Guang

2002-01-01

It is shown how the axial vector current of current quarks is related to that of constituent quarks within the framework of the global color symmetry model.Gluon dressing of the axial vector vertex and the quark self-energy functions are described by the inhomogeneous Bethe-Salpeter equation in the ladder approximation and the Schwinger Dyson equation in the rainbow approximation,respectively.

VECTOR BORNE TRANSMISSIBLE ZOONOSES IN MONTENEGRO

Directory of Open Access Journals (Sweden)

Gordana Mijovic

2012-02-01

Full Text Available Vector borne transmissible zoonoses are becoming more and more important in the group of emerging and re-emerging infections. We present the characteristics and actuality of this group of infectious diseases in Montenegro for the period 1998 - 2011. In examinations, standard epidemiological, clinical, serological, pathohistological diagnostic methods are employed. Natural conditions in Montenegro make it an important endemic area for more vector borne transmissible zoonoses. The changes of ecological characteristics, the vectors and infective agents, present the accidence for expansion and increasing importance of these infections in national pathology. According to the fact that it is an international port of nautical, continental and air traffic, Montenegro has responsibility for control and management of diseases belonging to the group of the travel and tropical diseases.

Existence and Stability of Solutions for Implicit Multivalued Vector Equilibrium Problems

Directory of Open Access Journals (Sweden)

Li Qiuying

2011-01-01

Full Text Available A class of implicit multivalued vector equilibrium problems is studied. By using the generalized Fan-Browder fixed point theorem, some existence results of solutions for the implicit multivalued vector equilibrium problems are obtained under some suitable assumptions. Moreover, a stability result of solutions for the implicit multivalued vector equilibrium problems is derived. These results extend and unify some recent results for implicit vector equilibrium problems, multivalued vector variational inequality problems, and vector variational inequality problems.

Meta-analysis of the Effects of Insect Vector Saliva on Host Immune Responses and Infection of Vector-Transmitted Pathogens: A Focus on Leishmaniasis

OpenAIRE

Ockenfels, Brittany; Michael, Edwin; McDowell, Mary Ann

2014-01-01

A meta-analysis of the effects of vector saliva on the immune response and progression of vector-transmitted disease, specifically with regard to pathology, infection level, and host cytokine levels was conducted. Infection in the absence or presence of saliva in naïve mice was compared. In addition, infection in mice pre-exposed to uninfected vector saliva was compared to infection in unexposed mice. To control for differences in vector and pathogen species, mouse strain, and experimental de...

Urbanization, land tenure security and vector-borne Chagas disease

Science.gov (United States)

Levy, Michael Z.; Barbu, Corentin M.; Castillo-Neyra, Ricardo; Quispe-Machaca, Victor R.; Ancca-Juarez, Jenny; Escalante-Mejia, Patricia; Borrini-Mayori, Katty; Niemierko, Malwina; Mabud, Tarub S.; Behrman, Jere R.; Naquira-Velarde, Cesar

2014-01-01

Modern cities represent one of the fastest growing ecosystems on the planet. Urbanization occurs in stages; each stage characterized by a distinct habitat that may be more or less susceptible to the establishment of disease vector populations and the transmission of vector-borne pathogens. We performed longitudinal entomological and epidemiological surveys in households along a 1900 × 125 m transect of Arequipa, Peru, a major city of nearly one million inhabitants, in which the transmission of Trypanosoma cruzi, the aetiological agent of Chagas disease, by the insect vector Triatoma infestans, is an ongoing problem. The transect spans a cline of urban development from established communities to land invasions. We find that the vector is tracking the development of the city, and the parasite, in turn, is tracking the dispersal of the vector. New urbanizations are free of vector infestation for decades. T. cruzi transmission is very recent and concentrated in more established communities. The increase in land tenure security during the course of urbanization, if not accompanied by reasonable and enforceable zoning codes, initiates an influx of construction materials, people and animals that creates fertile conditions for epidemics of some vector-borne diseases. PMID:24990681

Sharp Efficiency for Vector Equilibrium Problems on Banach Spaces

Directory of Open Access Journals (Sweden)

Si-Huan Li

2013-01-01

Full Text Available The concept of sharp efficient solution for vector equilibrium problems on Banach spaces is proposed. Moreover, the Fermat rules for local efficient solutions of vector equilibrium problems are extended to the sharp efficient solutions by means of the Clarke generalized differentiation and the normal cone. As applications, some necessary optimality conditions and sufficient optimality conditions for local sharp efficient solutions of a vector optimization problem with an abstract constraint and a vector variational inequality are obtained, respectively.

Vector Directional Distance Rational Hybrid Filters for Color Image Restoration

Directory of Open Access Journals (Sweden)

L. Khriji

2005-12-01

Full Text Available A new class of nonlinear filters, called vector-directional distance rational hybrid filters (VDDRHF for multispectral image processing, is introduced and applied to color image-filtering problems. These filters are based on rational functions (RF. The VDDRHF filter is a two-stage filter, which exploits the features of the vector directional distance filter (VDDF, the center weighted vector directional distance filter (CWVDDF and those of the rational operator. The filter output is a result of vector rational function (VRF operating on the output of three sub-functions. Two vector directional distance (VDDF filters and one center weighted vector directional distance filter (CWVDDF are proposed to be used in the first stage due to their desirable properties, such as, noise attenuation, chromaticity retention, and edges and details preservation. Experimental results show that the new VDDRHF outperforms a number of widely known nonlinear filters for multi-spectral image processing such as the vector median filter (VMF, the generalized vector directional filters (GVDF and distance directional filters (DDF with respect to all criteria used.

Great Ellipse Route Planning Based on Space Vector

Directory of Open Access Journals (Sweden)

LIU Wenchao

2015-07-01

Full Text Available Aiming at the problem of navigation error caused by unified earth model in great circle route planning using sphere model and modern navigation equipment using ellipsoid mode, a method of great ellipse route planning based on space vector is studied. By using space vector algebra method, the vertex of great ellipse is solved directly, and description of great ellipse based on major-axis vector and minor-axis vector is presented. Then calculation formulas of great ellipse azimuth and distance are deduced using two basic vectors. Finally, algorithms of great ellipse route planning are studied, especially equal distance route planning algorithm based on Newton-Raphson(N-R method. Comparative examples show that the difference of route planning between great circle and great ellipse is significant, using algorithms of great ellipse route planning can eliminate the navigation error caused by the great circle route planning, and effectively improve the accuracy of navigation calculation.

Nonlinear dynamics of a vectored thrust aircraft

DEFF Research Database (Denmark)

Sørensen, C.B; Mosekilde, Erik

1996-01-01

With realistic relations for the aerodynamic coefficients, numerical simulations are applied to study the longitudional dynamics of a thrust vectored aircraft. As function of the thrust magnitude and the thrust vectoring angle the equilibrium state exhibits two saddle-node bifurcations and three...

Vector velocity ultrasound—a new ultrasound technique

DEFF Research Database (Denmark)

Lönn, Lars; Jensen, Jørgen Arendt; Olesen, Jacob Bjerring

2018-01-01

• Vector fow techniques, with their many advantages over conventional Doppler techniques, are powerful alternatives for blood fow evaluation. • Vector fow imaging can visualise complex fow; refne the classic fow parameters; and introduce new fow parameters and insonation windows. • These factors...

morphological identification of malaria vectors within anopheles

African Journals Online (AJOL)

DR. AMIN

Africa among the human population. Determination of risk of malaria transmission requires quick and accurate methods of identification of Anopheles mosquitoes especially when targeting vector control. (Maxwell, et al., 2003). Anopheles mosquito transmits malaria. The most important vectors of malaria are members of.

[Conflicts and vector-borne diseases

DEFF Research Database (Denmark)

Bygbjerg, Ib Christian

2010-01-01

Based on literature and personal experiences, vector-borne diseases and conflicts are reviewed. Simple rapid diagnostic tests for three important parasitoses are available. Resort is often made to case definitions and to presumptive treatment. Resistance is an emerging problem. Vaccines are still...... not available for most diseases. Promising preventive methods, including long-lasting impregnated bed-nets and tents, are available. War has been an impetus for disclosing life-cycles of vector-borne diseases and for control methods; peace, reconciliation and poverty reduction are required to achieve lasting...

Topological vector spaces and distributions

CERN Document Server

Horvath, John

2012-01-01

""The most readable introduction to the theory of vector spaces available in English and possibly any other language.""-J. L. B. Cooper, MathSciNet ReviewMathematically rigorous but user-friendly, this classic treatise discusses major modern contributions to the field of topological vector spaces. The self-contained treatment includes complete proofs for all necessary results from algebra and topology. Suitable for undergraduate mathematics majors with a background in advanced calculus, this volume will also assist professional mathematicians, physicists, and engineers.The precise exposition o

Isomorphism Theorem on Vector Spaces over a Ring

Directory of Open Access Journals (Sweden)

Futa Yuichi

2017-10-01

Full Text Available In this article, we formalize in the Mizar system [1, 4] some properties of vector spaces over a ring. We formally prove the first isomorphism theorem of vector spaces over a ring. We also formalize the product space of vector spaces. ℤ-modules are useful for lattice problems such as LLL (Lenstra, Lenstra and Lovász [5] base reduction algorithm and cryptographic systems [6, 2].

RNA Interference in Insect Vectors for Plant Viruses

OpenAIRE

Kanakala, Surapathrudu; Ghanim, Murad

2016-01-01

Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi) was recently suggested as a promising strategy for controlling insect pests...

Simian virus 40 vectors for pulmonary gene therapy

Directory of Open Access Journals (Sweden)

Oppenheim Ariella

2007-10-01

Full Text Available Abstract Background Sepsis remains the leading cause of death in critically ill patients. One of the primary organs affected by sepsis is the lung, presenting as the Acute Respiratory Distress Syndrome (ARDS. Organ damage in sepsis involves an alteration in gene expression, making gene transfer a potential therapeutic modality. This work examines the feasibility of applying simian virus 40 (SV40 vectors for pulmonary gene therapy. Methods Sepsis-induced ARDS was established by cecal ligation double puncture (2CLP. SV40 vectors carrying the luciferase reporter gene (SV/luc were administered intratracheally immediately after sepsis induction. Sham operated (SO as well as 2CLP rats given intratracheal PBS or adenovirus expressing luciferase served as controls. Luc transduction was evaluated by in vivo light detection, immunoassay and luciferase mRNA detection by RT-PCR in tissue harvested from septic rats. Vector abundance and distribution into alveolar cells was evaluated using immunostaining for the SV40 VP1 capsid protein as well as by double staining for VP1 and for the surfactant protein C (proSP-C. Immunostaining for T-lymphocytes was used to evaluate the cellular immune response induced by the vector. Results Luc expression measured by in vivo light detection correlated with immunoassay from lung tissue harvested from the same rats. Moreover, our results showed vector presence in type II alveolar cells. The vector did not induce significant cellular immune response. Conclusion In the present study we have demonstrated efficient uptake and expression of an SV40 vector in the lungs of animals with sepsis-induced ARDS. These vectors appear to be capable of in vivo transduction of alveolar type II cells and may thus become a future therapeutic tool.

Polarization observables D/sub NN/, P and A for vector pp → vector pπ+n at 800 MeV

International Nuclear Information System (INIS)

Bonner, B.E.; McNaughton, M.W.; van Dyck, O.B.

1983-01-01

In conjunction with a vector polarization transfer measurement in the vector pp → vector dπ + reaction, we also obtained data on polarization observables for vector pp → vector pπ + n at 800 MeV incident proton energy. Scattered protons were detected in a spectrometer at angles from 5 0 to 11 0 . Pions were detected in coincidence at angles 80 0 to 130 0 . The proton momentum range covered was from 800 to 1300 MeV/c. The prominent peak observed near 1150 MeV/c in the proton spectrum is a reflection of Δ ++ production at center of mass angles from 0 0 to 30 0 . Regions of the spectrum corresponding to Δ ++ production at backward THETA/sub cm/ angles and to the 1 S 0 np final state interaction fall below the momentum acceptance limit for the spectrometer setting used in the present measurements. The events were binned into five proton momentum bins for the determination of the polarization observables D/sub NN/, P, and A

Vectorization of the KENO V.a criticality safety code

International Nuclear Information System (INIS)

Hollenbach, D.F.; Dodds, H.L.; Petrie, L.M.

1991-01-01

The development of the vector processor, which is used in the current generation of supercomputers and is beginning to be used in workstations, provides the potential for dramatic speed-up for codes that are able to process data as vectors. Unfortunately, the stochastic nature of Monte Carlo codes prevents the old scalar version of these codes from taking advantage of the vector processors. New Monte Carlo algorithms that process all the histories undergoing the same event as a batch are required. Recently, new vectorized Monte Carlo codes have been developed that show significant speed-ups when compared to the scalar version of themselves or equivalent codes. This paper discusses the vectorization of an already existing and widely used criticality safety code, KENO V.a All the changes made to KENO V.a are transparent to the user making it possible to upgrade from the standard scalar version of KENO V.a to the vectorized version without learning a new code

Reducing vector-borne disease by empowering farmers in integrated vector management

NARCIS (Netherlands)

Berg, van den H.; Hildebrand, von A.; Ragunathan, V.; Das, P.K.

2007-01-01

PROBLEM: Irrigated agriculture exposes rural people to health risks associated with vector-borne diseases and pesticides used in agriculture and for public health protection. Most developing countries lack collaboration between the agricultural and health sectors to jointly address these problems.

Effects of Vector Backbone and Pseudotype on Lentiviral Vector-mediated Gene Transfer: Studies in Infant ADA-Deficient Mice and Rhesus Monkeys

Science.gov (United States)

Carbonaro Sarracino, Denise; Tarantal, Alice F; Lee, C Chang I.; Martinez, Michele; Jin, Xiangyang; Wang, Xiaoyan; Hardee, Cinnamon L; Geiger, Sabine; Kahl, Christoph A; Kohn, Donald B

2014-01-01

Systemic delivery of a lentiviral vector carrying a therapeutic gene represents a new treatment for monogenic disease. Previously, we have shown that transfer of the adenosine deaminase (ADA) cDNA in vivo rescues the lethal phenotype and reconstitutes immune function in ADA-deficient mice. In order to translate this approach to ADA-deficient severe combined immune deficiency patients, neonatal ADA-deficient mice and newborn rhesus monkeys were treated with species-matched and mismatched vectors and pseudotypes. We compared gene delivery by the HIV-1-based vector to murine γ-retroviral vectors pseudotyped with vesicular stomatitis virus-glycoprotein or murine retroviral envelopes in ADA-deficient mice. The vesicular stomatitis virus-glycoprotein pseudotyped lentiviral vectors had the highest titer and resulted in the highest vector copy number in multiple tissues, particularly liver and lung. In monkeys, HIV-1 or simian immunodeficiency virus vectors resulted in similar biodistribution in most tissues including bone marrow, spleen, liver, and lung. Simian immunodeficiency virus pseudotyped with the gibbon ape leukemia virus envelope produced 10- to 30-fold lower titers than the vesicular stomatitis virus-glycoprotein pseudotype, but had a similar tissue biodistribution and similar copy number in blood cells. The relative copy numbers achieved in mice and monkeys were similar when adjusted to the administered dose per kg. These results suggest that this approach can be scaled-up to clinical levels for treatment of ADA-deficient severe combined immune deficiency subjects with suboptimal hematopoietic stem cell transplantation options. PMID:24925206

Effects of vector backbone and pseudotype on lentiviral vector-mediated gene transfer: studies in infant ADA-deficient mice and rhesus monkeys.

Science.gov (United States)

Carbonaro Sarracino, Denise; Tarantal, Alice F; Lee, C Chang I; Martinez, Michele; Jin, Xiangyang; Wang, Xiaoyan; Hardee, Cinnamon L; Geiger, Sabine; Kahl, Christoph A; Kohn, Donald B

2014-10-01

Systemic delivery of a lentiviral vector carrying a therapeutic gene represents a new treatment for monogenic disease. Previously, we have shown that transfer of the adenosine deaminase (ADA) cDNA in vivo rescues the lethal phenotype and reconstitutes immune function in ADA-deficient mice. In order to translate this approach to ADA-deficient severe combined immune deficiency patients, neonatal ADA-deficient mice and newborn rhesus monkeys were treated with species-matched and mismatched vectors and pseudotypes. We compared gene delivery by the HIV-1-based vector to murine γ-retroviral vectors pseudotyped with vesicular stomatitis virus-glycoprotein or murine retroviral envelopes in ADA-deficient mice. The vesicular stomatitis virus-glycoprotein pseudotyped lentiviral vectors had the highest titer and resulted in the highest vector copy number in multiple tissues, particularly liver and lung. In monkeys, HIV-1 or simian immunodeficiency virus vectors resulted in similar biodistribution in most tissues including bone marrow, spleen, liver, and lung. Simian immunodeficiency virus pseudotyped with the gibbon ape leukemia virus envelope produced 10- to 30-fold lower titers than the vesicular stomatitis virus-glycoprotein pseudotype, but had a similar tissue biodistribution and similar copy number in blood cells. The relative copy numbers achieved in mice and monkeys were similar when adjusted to the administered dose per kg. These results suggest that this approach can be scaled-up to clinical levels for treatment of ADA-deficient severe combined immune deficiency subjects with suboptimal hematopoietic stem cell transplantation options.

Generation of arbitrary vector beams with liquid crystal polarization converters and vector-photoaligned q-plates

International Nuclear Information System (INIS)

Chen, Peng; Ji, Wei; Wei, Bing-Yan; Hu, Wei; Lu, Yan-Qing; Chigrinov, Vladimir

2015-01-01

Arbitrary vector beams (VBs) are realized by the designed polarization converters and corresponding vector-photoaligned q-plates. The polarization converter is a specific twisted nematic cell with one substrate homogeneously aligned and the other space-variantly aligned. By combining a polarization-sensitive alignment agent with a dynamic micro-lithography system, various categories of liquid crystal polarization converters are demonstrated. Besides, traditional radially/azimuthally polarized light, high-order and multi-ringed VBs, and a VB array with different orders are generated. The obtained converters are further utilized as polarization masks to implement vector-photoaligning. The technique facilitates both the volume duplication of these converters and the generation of another promising optical element, the q-plate, which is suitable for the generation of VBs for coherent lasers. The combination of proposed polarization converters and correspondingly fabricated q-plates would drastically enhance the capability of polarization control and may bring more possibilities for the design of photonic devices

Black hole superradiance signatures of ultralight vectors

Science.gov (United States)

Baryakhtar, Masha; Lasenby, Robert; Teo, Mae

2017-08-01

The process of superradiance can extract angular momentum and energy from astrophysical black holes (BHs) to populate gravitationally bound states with an exponentially large number of light bosons. We analytically calculate superradiant growth rates for vectors around rotating BHs in the regime where the vector Compton wavelength is much larger than the BH size. Spin-1 bound states have superradiance times as short as a second around stellar BHs, growing up to a thousand times faster than their spin-0 counterparts. The fast rates allow us to use measurements of rapidly spinning BHs in x-ray binaries to exclude a wide range of masses for weakly coupled spin-1 particles, 5 ×10-14-2 ×10-11 eV ; lighter masses in the range 6 ×10-20-2 ×10-17 eV start to be constrained by supermassive BH spin measurements at a lower level of confidence. We also explore routes to detection of new vector particles possible with the advent of gravitational wave (GW) astronomy. The LIGO-Virgo Collaboration could discover hints of a new light vector particle in statistical analyses of masses and spins of merging BHs. Vector annihilations source continuous monochromatic gravitational radiation which could be observed by current GW observatories. At design sensitivity, Advanced LIGO may measure up to thousands of annihilation signals from within the Milky Way, while hundreds of BHs born in binary mergers across the observable Universe may superradiate vector bound states and become new beacons of monochromatic gravitational waves.

Nonseparable closed vector subspaces of separable topological vector spaces

Czech Academy of Sciences Publication Activity Database

Kąkol, Jerzy; Leiderman, A. G.; Morris, S. A.

2017-01-01

Roč. 182, č. 1 (2017), s. 39-47 ISSN 0026-9255 R&D Projects: GA ČR GF16-34860L Institutional support: RVO:67985840 Keywords : locally convex topological vector space * separable topological space Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.716, year: 2016 https://link.springer.com/article/10.1007%2Fs00605-016-0876-2

Researches on Key Algorithms in Analogue Seismogram Records Vectorization

Directory of Open Access Journals (Sweden)

Maofa WANG

2014-09-01

Full Text Available History paper seismograms are very important information for earthquake monitoring and prediction, and the vectorization of paper seismograms is a very import problem to be resolved. In our study, a new tracing algorithm for simulated seismogram curves based on visual filed feature is presented. We also give out the technological process to vectorizing simulated seismograms, and an analog seismic record vectorization system has been accomplished independently. Using it, we can precisely and speedy vectorize analog seismic records (need professionals to participate interactively.

Investigation of propagation dynamics of truncated vector vortex beams.

Science.gov (United States)

Srinivas, P; Perumangatt, C; Lal, Nijil; Singh, R P; Srinivasan, B

2018-06-01

In this Letter, we experimentally investigate the propagation dynamics of truncated vector vortex beams generated using a Sagnac interferometer. Upon focusing, the truncated vector vortex beam is found to regain its original intensity structure within the Rayleigh range. In order to explain such behavior, the propagation dynamics of a truncated vector vortex beam is simulated by decomposing it into the sum of integral charge beams with associated complex weights. We also show that the polarization of the truncated composite vector vortex beam is preserved all along the propagation axis. The experimental observations are consistent with theoretical predictions based on previous literature and are in good agreement with our simulation results. The results hold importance as vector vortex modes are eigenmodes of the optical fiber.

A new mass relation among the hadron vector resonances

CERN Document Server

Chizhov, M.V.

2001-01-01

We show that the hadron vector resonances are described by fields transforming according to different inequivalent representations of the Lorentz group: (1/2,1/2) and (1,0)+(0,1). The vector representation (1/2,1/2) is well studied and corresponds to the gauge fields. On the other hand, the chiral representations (1,0) and (0,1) are described by the second rank antisymmetric tensor fields, for which interaction theory has not yet been constructed. In the framework of the phenomenological Nambu - Jona-Lasinio approach we have introduced and used all these fields for a description of the vector resonances. A new mass relation between low-lying hadron vector and axial-vector resonances is obtained. This relation is in agreement with the present experimental data.

Chickering's Vectors and the Adult Child Experience.

Science.gov (United States)

Sitten, Robin J.

This document looks at the college student who is an adult child from a dysfunctional family, applying Chickering's seven vectors of college-age student development to that student's experiences at college. Each of Chickering's seven vectors (developing competence, managing emotions, developing autonomy, establishing identity, freeing…

Zika and its vector mosquitoes in Mexico

Directory of Open Access Journals (Sweden)

Luis del Carpio-Orantes

2018-06-01

Full Text Available In the present study, we carried out a review on the potential vectors of the Zika virus in the Americas, specifically in Mexico. Being vectors of the Culicidae family, they have great predominance in those territories, which could facilitate viral dissemination.

Triviality and Split of Vector Bundles on Rationally Connected Varieties

OpenAIRE

Pan, Xuanyu

2013-01-01

In this paper, we give a simple proof of a triviality criterion due to I.Biswas and J.Pedro and P.Dos Santos. We also prove a vector bundle on a homogenous space is trivial if and only if the restrictions of the vector bundle to Schubert lines are trivial. Using this result and Chern classes of vector bundles, we give a general criterion of a uniform vector bundle on a homogenous space to be splitting. As an application, we prove a uniform vector bundle on classical Grassmannians and quadrics...

Switching non-local vector median filter

Science.gov (United States)

Matsuoka, Jyohei; Koga, Takanori; Suetake, Noriaki; Uchino, Eiji

2016-04-01

This paper describes a novel image filtering method that removes random-valued impulse noise superimposed on a natural color image. In impulse noise removal, it is essential to employ a switching-type filtering method, as used in the well-known switching median filter, to preserve the detail of an original image with good quality. In color image filtering, it is generally preferable to deal with the red (R), green (G), and blue (B) components of each pixel of a color image as elements of a vectorized signal, as in the well-known vector median filter, rather than as component-wise signals to prevent a color shift after filtering. By taking these fundamentals into consideration, we propose a switching-type vector median filter with non-local processing that mainly consists of a noise detector and a noise removal filter. Concretely, we propose a noise detector that proactively detects noise-corrupted pixels by focusing attention on the isolation tendencies of pixels of interest not in an input image but in difference images between RGB components. Furthermore, as the noise removal filter, we propose an extended version of the non-local median filter, we proposed previously for grayscale image processing, named the non-local vector median filter, which is designed for color image processing. The proposed method realizes a superior balance between the preservation of detail and impulse noise removal by proactive noise detection and non-local switching vector median filtering, respectively. The effectiveness and validity of the proposed method are verified in a series of experiments using natural color images.

[Vector transmitted diseases and climate changes in Europe].

Science.gov (United States)

Rossati, Antonella; Bargiacchi, Olivia; Kroumova, Vesselina; Garavelli, Pietro Luigi

2014-09-01

The increase in temperatures recorded since the mid-nineteenth century is unprecedented in the history of mankind. The consequences of climate changes are numerous and can affect human health through direct (extreme events, natural disasters) or indirect (alteration of the ecosystem) mechanisms. Climate changes have repercussions on ecosystems, agriculture, social conditions, migration, conflicts and the transmission mode of infectious diseases. Vector-borne diseases are infections transmitted by the bite of infected arthropods such as mosquitoes, ticks, triatomines, sand flies and flies. Epidemiological cornerstones of vector-borne diseases are: the ecology and behaviour of the host, the ecology and behaviour of the vector, and the population's degree of immunity. Mosquito vectors related to human diseases mainly belong to the genus Culex, Aedes and Mansonia. Climate changes in Europe have increased the spread of new vectors, such as Aedes albopictus, and in some situations have made it possible to sustain the autochthonous transmission of some diseases (outbreak of Chukungunya virus in northern Italy in 2007, cases of dengue in the South of France and in Croatia). Despite the eradication of malaria from Europe, anopheline carriers are still present, and they may allow the transmission of the disease if the climatic conditions favour the development of the vectors and their contacts with plasmodium carriers. The tick Ixodes ricinus is a vector whose expansion has been documented both in latitude and in altitude in relation to the temperature increase; at the same time the related main viral and bacterial infections have increased. In northern Italy and Germany, the appearance of Leishmaniasis has been associated to climatic conditions that favour the development of the vector Phlebotomus papatasi and the maturation of the parasite within the vector, although the increase of cases of visceral leishmaniasis is also related to host immune factors, particularly

Recent Advances in Non-viral Vectors for Gene Delivery

Science.gov (United States)

Guo, Xia; Huang, Leaf

2011-01-01

CONSPECTUS Non-viral vectors, typically based on cationic lipids or polymers, are preferred due to safety concerns with viral vectors. So far, non-viral vectors can proficiently transfect cells in culture, but obtaining efficient nanomedicines is far from evident. To overcome the hurdles associated with non-viral vectors is significant for improving delivery efficiency and therapeutic effect of nucleic acid. The drawbacks include the strong interaction of cationic delivery vehicles with blood components, uptake by the reticuloendothelial system (RES), toxicity, targeting ability of the carriers to the cells of interest, and so on. PEGylation is the predominant method used to reduce the binding of plasma proteins with non-viral vectors and minimize the clearance by RES after intravenous administration. The nanoparticles that are not rapidly cleared from the circulation accumulate in the tumors due to the enhanced permeability and retention effect, and the targeting ligands attached to the distal end of the PEGylated components allow binding to the receptors on the target cell surface. Neutral or anionic liposomes have been also developed for systemic delivery of nucleic acids in experimental animal model. Designing and synthesizing novel cationic lipids and polymers, and binding nucleic acid with peptides, targeting ligands, polymers, or environmentally sensitive moieties also attract many attentions for resolving the problems encountered by non-viral vectors. The application of inorganic nanoparticles in nucleic acid delivery is an emerging field, too. Recently, different classes of non-viral vectors appear to be converging and the features of different classes of non-viral vectors could be combined in one strategy. More hurdles associated with efficient nucleic acid delivery therefore might be expected to be overcome. In this account, we will focus on these novel non-viral vectors, which are classified into multifunctional hybrid nucleic acid vectors, novel

Synthetic Aperture Vector Flow Imaging

DEFF Research Database (Denmark)

Villagómez Hoyos, Carlos Armando

The main objective of this project was to continue the development of a synthetic aperture vector flow estimator. This type of estimator is capable of overcoming two of the major limitations in conventional ultrasound systems: 1) the inability to scan large region of interest with high temporal......, this thesis showed that novel information can be obtained with vector velocity methods providing quantitative estimates of blood flow and insight into the complexity of the hemodynamics dynamics. This could give the clinician a new tool in assessment and treatment of a broad range of diseases....

Learning with Support Vector Machines

CERN Document Server

Campbell, Colin

2010-01-01

Support Vectors Machines have become a well established tool within machine learning. They work well in practice and have now been used across a wide range of applications from recognizing hand-written digits, to face identification, text categorisation, bioinformatics, and database marketing. In this book we give an introductory overview of this subject. We start with a simple Support Vector Machine for performing binary classification before considering multi-class classification and learning in the presence of noise. We show that this framework can be extended to many other scenarios such a

Vaxvec: The first web-based recombinant vaccine vector database and its data analysis

Science.gov (United States)

Deng, Shunzhou; Martin, Carly; Patil, Rasika; Zhu, Felix; Zhao, Bin; Xiang, Zuoshuang; He, Yongqun

2015-01-01

A recombinant vector vaccine uses an attenuated virus, bacterium, or parasite as the carrier to express a heterologous antigen(s). Many recombinant vaccine vectors and related vaccines have been developed and extensively investigated. To compare and better understand recombinant vectors and vaccines, we have generated Vaxvec (http://www.violinet.org/vaxvec), the first web-based database that stores various recombinant vaccine vectors and those experimentally verified vaccines that use these vectors. Vaxvec has now included 59 vaccine vectors that have been used in 196 recombinant vector vaccines against 66 pathogens and cancers. These vectors are classified to 41 viral vectors, 15 bacterial vectors, 1 parasitic vector, and 1 fungal vector. The most commonly used viral vaccine vectors are double-stranded DNA viruses, including herpesviruses, adenoviruses, and poxviruses. For example, Vaxvec includes 63 poxvirus-based recombinant vaccines for over 20 pathogens and cancers. Vaxvec collects 30 recombinant vector influenza vaccines that use 17 recombinant vectors and were experimentally tested in 7 animal models. In addition, over 60 protective antigens used in recombinant vector vaccines are annotated and analyzed. User-friendly web-interfaces are available for querying various data in Vaxvec. To support data exchange, the information of vaccine vectors, vaccines, and related information is stored in the Vaccine Ontology (VO). Vaxvec is a timely and vital source of vaccine vector database and facilitates efficient vaccine vector research and development. PMID:26403370

Axisymmetric thrust-vectoring nozzle performance prediction

International Nuclear Information System (INIS)

Wilson, E. A.; Adler, D.; Bar-Yoseph, P.Z

1998-01-01

Throat-hinged geometrically variable converging-diverging thrust-vectoring nozzles directly affect the jet flow geometry and rotation angle at the nozzle exit as a function of the nozzle geometry, the nozzle pressure ratio and flight velocity. The consideration of nozzle divergence in the effective-geometric nozzle relation is theoretically considered here for the first time. In this study, an explicit calculation procedure is presented as a function of nozzle geometry at constant nozzle pressure ratio, zero velocity and altitude, and compared with experimental results in a civil thrust-vectoring scenario. This procedure may be used in dynamic thrust-vectoring nozzle design performance predictions or analysis for civil and military nozzles as well as in the definition of initial jet flow conditions in future numerical VSTOL/TV jet performance studies

Application of Vector Triggering Random Decrement

DEFF Research Database (Denmark)

Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

result is a Random Decrement function from each measurement. In traditional Random Decrement estimation the triggering condition is a scalar condition, which should only be fulfilled in a single measurement. In vector triggering Random Decrement the triggering condition is a vector condition......This paper deals with applications of the vector triggering Random Decrement technique. This technique is new and developed with the aim of minimizing estimation time and identification errors. The theory behind the technique is discussed in an accompanying paper. The results presented...... in this paper should be regarded as a further documentation of the technique. The key point in Random Decrement estimation is the formulation of a triggering condition. If the triggering condition is fulfilled a time segment from each measurement is picked out and averaged with previous time segments. The final...

Application of Vector Triggering Random Decrement

DEFF Research Database (Denmark)

Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

1997-01-01

result is a Random Decrement function from each measurement. In traditional Random Decrement estimation the triggering condition is a scalar condition, which should only be fulfilled in a single measurement. In vector triggering Random Decrement the triggering condition is a vector condition......This paper deals with applications of the vector triggering Random Decrement technique. This technique is new and developed with the aim of minimizing estimation time and identification errors. The theory behind the technique is discussed in an accompanying paper. The results presented...... in this paper should be regarded as a further documentation of the technique. The key point in Random Decrement estimation is the formulation of a triggering condition. If the triggering condition is fulfilled a time segment from each measurement is picked out and averaged with previous time segments. The final...

Redshift-space distortions from vector perturbations

Science.gov (United States)

Bonvin, Camille; Durrer, Ruth; Khosravi, Nima; Kunz, Martin; Sawicki, Ignacy

2018-02-01

We compute a general expression for the contribution of vector perturbations to the redshift space distortion of galaxy surveys. We show that they contribute to the same multipoles of the correlation function as scalar perturbations and should thus in principle be taken into account in data analysis. We derive constraints for next-generation surveys on the amplitude of two sources of vector perturbations, namely non-linear clustering and topological defects. While topological defects leave a very small imprint on redshift space distortions, we show that the multipoles of the correlation function are sensitive to vorticity induced by non-linear clustering. Therefore future redshift surveys such as DESI or the SKA should be capable of measuring such vector modes, especially with the hexadecapole which appears to be the most sensitive to the presence of vorticity.

General projective relativity and the vector-tensor gravitational field

International Nuclear Information System (INIS)

Arcidiacono, G.

1986-01-01

In the general projective relativity, the induced 4-dimensional metric is symmetric in three cases, and we obtain the vector-tensor, the scalar-tensor, and the scalar-vector-tensor theories of gravitation. In this work we examine the vector-tensor theory, similar to the Veblen's theory, but with a different physical interpretation

VECTORS OF MALARIA AND FILARIASIS IN INDONESIA

Directory of Open Access Journals (Sweden)

Hoedojo Hoedojo

2012-09-01

Full Text Available Malaria at present is still one of the important mosquito-borne diseases in Indonesia. The disease is widespread all over the country and involves nearly all islands. Sixteen Anopheles species have been reconfirmed as malaria vectors. They were distributed geographi­cally as follows: Coastal areas and lagoons ------------------------------------- An sundaicus and An.subpictus Cultivated ricefields and swampy areas -------------------- An.aconitus, An.barbirostris, An.nigerrimus and An.sinensis Forest inland areas in shaded temporary pools, muddy animal wallows and hoof-prints -------------------------------------------------------- An.balabacensis, An.bancrofti, An.farauti, An.koliensis and An.punctulatus Swamp forest edge in ditches with vegeta- ---------------- An.letifer and An.ludlowae don Hilly areas in seepages, streams and clear moving water ---------------------------------------------- Anflavirostris, An.maculatus and Anminimus.   The species (of most general importance is An.sundaicus, which is restricted by its preference for brackish water and is prevalent in coastal areas of Java. Their types in behaviour of An.sundaicus appear as follows : 1. An.sundaicus in South Coast of Java in general. This species is essentially anthropophilic, exophagic and rests outdoor. It shows susceptible to DDT. 2. An.sundaicus in Cilacap, Central Java. This mosquito is a pure anthropophilic form. It bites man in houses and outdoors, rests indoors and is known resistant to DDT. 3. An.sundaicus in Yogyakarta and Purworejo, Central Java. This mosquito is a strong zoophilic species. It rests and prefers to bite outdoors and shows tolerance to DDT. Human filariasis in Indonesia is the result of infection by three endemic species, namely, Wuchereria bancrofti, Brugia malayi, and Brugia timori.W.bancrofti infection is found in both urban and rural areas. Twenty species of mosquitoes are confirmed as filariasis vectors. The urban type bancroftian filariasis

Genetic architecture of downy mildew resistance in cucumber

Science.gov (United States)

Downy mildew (DM) caused by the obligate oomycete Pseudoperonospora cubensis is the most devastating fungal disease to cucumber production. The molecular mechanism of DM resistance in cucumber is not well understood. We conducted QTL mapping for DM resistances in four cucumber lines including WI7120...

Transmutations between singular and subsingular vectors of the N = 2 superconformal algebras

International Nuclear Information System (INIS)

Doerrzapf, Matthias; Gato-Rivera, Beatriz

1999-01-01

We present subsingular vectors of the N = 2 superconformal algebras other than the ones which become singular in chiral Verma modules, reported recently by Gato-Rivera and Rosado. We show that two large classes of singular vectors of the topological algebra become subsingular vectors of the antiperiodic NS algebra under the topological untwistings. These classes consist of BRST-invariant singular vectors with relative charges q = -2, -1 and zero conformal weight, and nolabel singular vectors with q = 0, -1. In turn the resulting NS subsingular vectors are transformed by the spectral flows into subsingular and singular vectors of the periodic R algebra. We write down these singular and subsingular vectors starting from the topological singular vectors at levels 1 and 2

Arterial secondary blood flow patterns visualized with vector flow ultrasound

DEFF Research Database (Denmark)

Pedersen, Mads Møller; Pihl, Michael Johannes; Hansen, Jens Munk

2011-01-01

This study presents the first quantification and visualisation of secondary flow patterns with vector flow ultrasound. The first commercial implementation of the vector flow method Transverse Oscillation was used to obtain in-vivo, 2D vector fields in real-time. The hypothesis of this study...... was that the rotational direction is constant within each artery. Three data sets of 10 seconds were obtained from three main arteries in healthy volunteers. For each data set the rotational flow patterns were identified during the diastole. Each data set contains a 2D vector field over time and with the vector angles...

Isometric Reflection Vectors and Characterizations of Hilbert Spaces

Directory of Open Access Journals (Sweden)

Donghai Ji

2014-01-01

Full Text Available A known characterization of Hilbert spaces via isometric reflection vectors is based on the following implication: if the set of isometric reflection vectors in the unit sphere SX of a Banach space X has nonempty interior in SX, then X is a Hilbert space. Applying a recent result based on well-known theorem of Kronecker from number theory, we improve this by substantial reduction of the set of isometric reflection vectors needed in the hypothesis.

A Hybrid Pressure and Vector Sensor Towed Array

National Research Council Canada - National Science Library

Huang, Dehua

2008-01-01

The invention as disclosed is of a combined acoustic pressure and acoustic vector sensor array, where multiple acoustic pressure sensors are integrated with an acoustic vector sensor in a towed array...

Probabilistic Extraction Of Vectors In PIV

Science.gov (United States)

Humphreys, William M., Jr.

1994-01-01

Probabilistic technique for extraction of velocity vectors in particle-image velocimetry (PIV) implemented with much less computation. Double-exposure photograph of particles in flow illuminated by sheet of light provides data on velocity field of flow. Photograph converted into video image then digitized and processed by computer into velocity-field data. Velocity vectors in interrogation region chosen from magnitude and angle histograms constructed from centroid map of region.

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Science.gov (United States)

2010-07-01

... vector attraction reduction. 503.15 Section 503.15 Protection of Environment ENVIRONMENTAL PROTECTION... § 503.15 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge... reclamation site. (c) Vector attraction reduction—sewage sludge. (1) One of the vector attraction reduction...

First measurement of the helicity-dependent vector gamma)vector(p)->p eta differential cross-section

CERN Document Server

Ahrens, J; Aulenbacher, K; Beck, R; Drechsel, D; Von Harrach, D; Heid, E; Altieri, S; Annand, J R M; Anton, G; Bradtke, C; Görtz, S; Harmsen, J; Braghieri, A; D'Hose, N; Dutz, H; Grabmayr, P; Hansen, K; Hasegawa, S; Hasegawa, T; Helbing, K; Holvoet, H; Van Hoorebeke, L; Horikawa, N; Iwata, T; Jahn, O; Jennewein, P; Kageya, T; Kiel, B; Klein, F; Kondratiev, R; Kossert, K; Krimmer, J; Lang, M; Lannoy, B; Leukel, R; Lisin, V; Matsuda, T; McGeorge, J C; Meier, A; Menze, D; Meyer, Werner T; Michel, T; Naumann, J; Panzeri, A; Pedroni, P; Pinelli, T; Preobrajenski, I; Radtke, E; Reichert, E; Reicherz, G; Rohlof, C; Rosner, G; Ryckbosch, D; Sauer, M C; Schoch, B; Schumacher, M; Seitz, B; Speckner, T; Takabayashi, N; Tamas, G; Thomas, A; Van De Vyver, R; Wakai, A; Weihofen, W; Wissmann, F; Zapadtka, F; Zeitler, G

2003-01-01

The helicity dependence of the vector(gamma)vector(p)->p eta reaction has been measured for the first time at a center-of-mass angle theta sup * subeta=70 in the photon energy range from 780 MeV to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4 pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. The helicity 3/2 cross-section is found to be small and the results for helicity 1/2 agree with predictions from the MAID analysis. (orig.)

Dynamical creation of complex vector solitons in spinor Bose-Einstein condensates

International Nuclear Information System (INIS)

Xiong Bo; Gong Jiangbin

2010-01-01

By numerical simulations of the Gross-Pitaevskii mean-field equations, we show that the dynamical creation of stable complex vector solitons in a homogeneous spin-1 Bose-Einstein condensate can be achieved by applying a localized magnetic field for a certain duration, with the initial uniform density prepared differently for the formation of different vector solitons. In particular, it is shown that stable dark-bright-dark vector solitons, dark-bright-bright vector solitons, and other analogous solutions can be dynamically created. It is also found that the peak intensity and the group velocity of the vector solitons thus generated can be tuned by adjusting the applied magnetic field. Extensions of our approach also allow for the creation of vector-soliton chains or the pumping of many vector solitons. The results can be useful for possible vector-soliton-based applications of dilute Bose-Einstein condensates.

GAP Land Cover - Vector

Data.gov (United States)

Minnesota Department of Natural Resources — This vector dataset is a detailed (1-acre minimum), hierarchically organized vegetation cover map produced by computer classification of combined two-season pairs of...

How effective is integrated vector management against malaria and lymphatic filariasis where the diseases are transmitted by the same vector?

Directory of Open Access Journals (Sweden)

Christopher M Stone

2014-12-01

Full Text Available The opportunity to integrate vector management across multiple vector-borne diseases is particularly plausible for malaria and lymphatic filariasis (LF control where both diseases are transmitted by the same vector. To date most examples of integrated control targeting these diseases have been unanticipated consequences of malaria vector control, rather than planned strategies that aim to maximize the efficacy and take the complex ecological and biological interactions between the two diseases into account.We developed a general model of malaria and LF transmission and derived expressions for the basic reproductive number (R0 for each disease. Transmission of both diseases was most sensitive to vector mortality and biting rate. Simulating different levels of coverage of long lasting-insecticidal nets (LLINs and larval control confirms the effectiveness of these interventions for the control of both diseases. When LF was maintained near the critical density of mosquitoes, minor levels of vector control (8% coverage of LLINs or treatment of 20% of larval sites were sufficient to eliminate the disease. Malaria had a far greater R0 and required a 90% population coverage of LLINs in order to eliminate it. When the mosquito density was doubled, 36% and 58% coverage of LLINs and larval control, respectively, were required for LF elimination; and malaria elimination was possible with a combined coverage of 78% of LLINs and larval control.Despite the low level of vector control required to eliminate LF, simulations suggest that prevalence of LF will decrease at a slower rate than malaria, even at high levels of coverage. If representative of field situations, integrated management should take into account not only how malaria control can facilitate filariasis elimination, but strike a balance between the high levels of coverage of (multiple interventions required for malaria with the long duration predicted to be required for filariasis elimination.

How effective is integrated vector management against malaria and lymphatic filariasis where the diseases are transmitted by the same vector?

Science.gov (United States)

Stone, Christopher M; Lindsay, Steve W; Chitnis, Nakul

2014-12-01

The opportunity to integrate vector management across multiple vector-borne diseases is particularly plausible for malaria and lymphatic filariasis (LF) control where both diseases are transmitted by the same vector. To date most examples of integrated control targeting these diseases have been unanticipated consequences of malaria vector control, rather than planned strategies that aim to maximize the efficacy and take the complex ecological and biological interactions between the two diseases into account. We developed a general model of malaria and LF transmission and derived expressions for the basic reproductive number (R0) for each disease. Transmission of both diseases was most sensitive to vector mortality and biting rate. Simulating different levels of coverage of long lasting-insecticidal nets (LLINs) and larval control confirms the effectiveness of these interventions for the control of both diseases. When LF was maintained near the critical density of mosquitoes, minor levels of vector control (8% coverage of LLINs or treatment of 20% of larval sites) were sufficient to eliminate the disease. Malaria had a far greater R0 and required a 90% population coverage of LLINs in order to eliminate it. When the mosquito density was doubled, 36% and 58% coverage of LLINs and larval control, respectively, were required for LF elimination; and malaria elimination was possible with a combined coverage of 78% of LLINs and larval control. Despite the low level of vector control required to eliminate LF, simulations suggest that prevalence of LF will decrease at a slower rate than malaria, even at high levels of coverage. If representative of field situations, integrated management should take into account not only how malaria control can facilitate filariasis elimination, but strike a balance between the high levels of coverage of (multiple) interventions required for malaria with the long duration predicted to be required for filariasis elimination.

Unsupervised learning of binary vectors: A Gaussian scenario

International Nuclear Information System (INIS)

Copelli, Mauro; Van den Broeck, Christian

2000-01-01

We study a model of unsupervised learning where the real-valued data vectors are isotropically distributed, except for a single symmetry-breaking binary direction B(set-membership sign){-1,+1} N , onto which the projections have a Gaussian distribution. We show that a candidate vector J undergoing Gibbs learning in this discrete space, approaches the perfect match J=B exponentially. In addition to the second-order ''retarded learning'' phase transition for unbiased distributions, we show that first-order transitions can also occur. Extending the known result that the center of mass of the Gibbs ensemble has Bayes-optimal performance, we show that taking the sign of the components of this vector (clipping) leads to the vector with optimal performance in the binary space. These upper bounds are shown generally not to be saturated with the technique of transforming the components of a special continuous vector, except in asymptotic limits and in a special linear case. Simulations are presented which are in excellent agreement with the theoretical results. (c) 2000 The American Physical Society

Vector-Parallel processing of the successive overrelaxation method

International Nuclear Information System (INIS)

Yokokawa, Mitsuo

1988-02-01

Successive overrelaxation method, called SOR method, is one of iterative methods for solving linear system of equations, and it has been calculated in serial with a natural ordering in many nuclear codes. After the appearance of vector processors, this natural SOR method has been changed for the parallel algorithm such as hyperplane or red-black method, in which the calculation order is modified. These methods are suitable for vector processors, and more high-speed calculation can be obtained compared with the natural SOR method on vector processors. In this report, a new scheme named 4-colors SOR method is proposed. We find that the 4-colors SOR method can be executed on vector-parallel processors and it gives the most high-speed calculation among all SOR methods according to results of the vector-parallel execution on the Alliant FX/8 multiprocessor system. It is also shown that the theoretical optimal acceleration parameters are equal among five different ordering SOR methods, and the difference between convergence rates of these SOR methods are examined. (author)

Robust and accurate vectorization of line drawings.

Science.gov (United States)

Hilaire, Xavier; Tombre, Karl

2006-06-01

This paper presents a method for vectorizing the graphical parts of paper-based line drawings. The method consists of separating the input binary image into layers of homogeneous thickness, skeletonizing each layer, segmenting the skeleton by a method based on random sampling, and simplifying the result. The segmentation method is robust with a best bound of 50 percent noise reached for indefinitely long primitives. Accurate estimation of the recognized vector's parameters is enabled by explicitly computing their feasibility domains. Theoretical performance analysis and expression of the complexity of the segmentation method are derived. Experimental results and comparisons with other vectorization systems are also provided.

Construction and decomposition of biorthogonal vector-valued wavelets with compact support

International Nuclear Information System (INIS)

Chen Qingjiang; Cao Huaixin; Shi Zhi

2009-01-01

In this article, we introduce vector-valued multiresolution analysis and the biorthogonal vector-valued wavelets with four-scale. The existence of a class of biorthogonal vector-valued wavelets with compact support associated with a pair of biorthogonal vector-valued scaling functions with compact support is discussed. A method for designing a class of biorthogonal compactly supported vector-valued wavelets with four-scale is proposed by virtue of multiresolution analysis and matrix theory. The biorthogonality properties concerning vector-valued wavelet packets are characterized with the aid of time-frequency analysis method and operator theory. Three biorthogonality formulas regarding them are presented.

On the calculation of multi-group fission spectrum vectors

International Nuclear Information System (INIS)

Mueller, E.Z.

1984-05-01

In this report, the problem of calculating fission spectrum vectors in a consistent manner is formulated. The practical implications of using fission spectrum vectors in multi-group transport calculations are also addressed. The significance of the weighting spectra used for the calculation of fission spectrum vectors is illustrated for the case of a simple neutronic assembly

Engineered XcmI cassette-containing vector for PCR-based ...

Indian Academy of Sciences (India)

Unknown

A simple and general method is described to construct a new vector bearing a synthetic XcmI cassette for direct cloning of PCR-amplified genes of interest. Cleavage of the vector with XcmI generates a linearized molecule with a single thymidine (T) overhang at the 3′ ends (T-vector) that facilitates TA cloning of PCR ...

Deep Support Vector Machines for Regression Problems

NARCIS (Netherlands)

Wiering, Marco; Schutten, Marten; Millea, Adrian; Meijster, Arnold; Schomaker, Lambertus

2013-01-01

In this paper we describe a novel extension of the support vector machine, called the deep support vector machine (DSVM). The original SVM has a single layer with kernel functions and is therefore a shallow model. The DSVM can use an arbitrary number of layers, in which lower-level layers contain

Techniques for vector analyzing power measurements of the sup 2 H(n vector,np)n breakup reaction at low energies

Energy Technology Data Exchange (ETDEWEB)

Howell, C.R.; Tornow, W.; Pfuetzner, H.G.; Li Anli; Roberts, M.L.; Murphy, K.; Felsher, P.D.; Weisel, G.J.; Naqvi, A.; Walter, R.L. (Duke Univ., Durham, NC (USA) Triangle Universities Nuclear Lab., Durham, NC (USA)); Lambert, J.M.; Treado, P.A. (Georgetown Univ., Washington, DC (USA). Dept. of Physics); Slaus, I. (Institut Rudjer Boskovic, Zagreb (Yugoslavia))

1990-05-10

Experimental methods to measure the vector analyzing powers over a broad range of kinematic configurations in the n-d breakup reaction have been developed at TUNL. These techniques employ the polarized beam facilities at TUNL and use the {sup 2}H(d vector, n vector){sup 3}He reaction as a source of low-energy polarized neutrons. Our methods permit measurements to a high statistical accuracy over a large fraction of three-nucleon phase space. The techniques are described and experimental spectra along with kinematic calculations are presented. (orig.).

Use of a mixture statistical model in studying malaria vectors density.

Directory of Open Access Journals (Sweden)

Olayidé Boussari

Full Text Available Vector control is a major step in the process of malaria control and elimination. This requires vector counts and appropriate statistical analyses of these counts. However, vector counts are often overdispersed. A non-parametric mixture of Poisson model (NPMP is proposed to allow for overdispersion and better describe vector distribution. Mosquito collections using the Human Landing Catches as well as collection of environmental and climatic data were carried out from January to December 2009 in 28 villages in Southern Benin. A NPMP regression model with "village" as random effect is used to test statistical correlations between malaria vectors density and environmental and climatic factors. Furthermore, the villages were ranked using the latent classes derived from the NPMP model. Based on this classification of the villages, the impacts of four vector control strategies implemented in the villages were compared. Vector counts were highly variable and overdispersed with important proportion of zeros (75%. The NPMP model had a good aptitude to predict the observed values and showed that: i proximity to freshwater body, market gardening, and high levels of rain were associated with high vector density; ii water conveyance, cattle breeding, vegetation index were associated with low vector density. The 28 villages could then be ranked according to the mean vector number as estimated by the random part of the model after adjustment on all covariates. The NPMP model made it possible to describe the distribution of the vector across the study area. The villages were ranked according to the mean vector density after taking into account the most important covariates. This study demonstrates the necessity and possibility of adapting methods of vector counting and sampling to each setting.

Dual AAV Vectors for Stargardt Disease.

Science.gov (United States)

Trapani, Ivana

2018-01-01

Stargardt disease (STGD1), due to mutations in the large ABCA4 gene, is the most common inherited macular degeneration in humans. Attempts at developing gene therapy approaches for treatment of STGD1 are currently ongoing. Among all the vectors available for gene therapy of inherited retinal diseases, those based on adeno-associated viruses (AAV) are the most promising given the efficacy shown in various animal models and their excellent safety profile in humans, as confirmed in many ongoing clinical trials. However, one of the main obstacles for the use of AAV is their limited effective packaging capacity of about 5 kb. Taking advantage of the AAV genome's ability to concatemerize , others and we have recently developed dual AAV vectors to overcome this limit. We tested dual AAV vectors for ABCA4 delivery, and found that they transduce efficiently both mouse and pig photoreceptors , and rescue the Abca4-/- mouse retinal phenotype, indicating their potential for gene therapy of STGD1. This chapter details how we designed dual AAV vectors for the delivery of the ABCA4 gene and describes the techniques that can be explored to evaluate dual AAV transduction efficiency in vitro and in the retina, and their efficacy in the mouse model of STGD1.

Space Vector Pulse Width Modulation of a Multi-Level Diode ...

African Journals Online (AJOL)

Space Vector Pulse Width Modulation of a Multi-Level Diode Clamped ... of MATLAB /SIMULINK modeling of the space vector pulse-width modulation and the ... two adjacent active vectors in determining the switching process of the multilevel ...

Prospects for Foamy Viral Vector Anti-HIV Gene Therapy

Directory of Open Access Journals (Sweden)

Arun K. Nalla

2016-03-01

Full Text Available Stem cell gene therapy approaches for Human Immunodeficiency Virus (HIV infection have been explored in clinical trials and several anti-HIV genes delivered by retroviral vectors were shown to block HIV replication. However, gammaretroviral and lentiviral based retroviral vectors have limitations for delivery of anti-HIV genes into hematopoietic stem cells (HSC. Foamy virus vectors have several advantages including efficient delivery of transgenes into HSC in large animal models, and a potentially safer integration profile. This review focuses on novel anti-HIV transgenes and the potential of foamy virus vectors for HSC gene therapy of HIV.

Malaria vector species in Colombia: a review

Directory of Open Access Journals (Sweden)

James Montoya-Lerma

2011-08-01

Full Text Available Here we present a comprehensive review of the literature on the vectorial importance of the major Anopheles malaria vectors in Colombia. We provide basic information on the geographical distribution, altitudinal range, immature habitats, adult behaviour, feeding preferences and anthropophily, endophily and infectivity rates. We additionally review information on the life cycle, longevity and population fluctuation of Colombian Anopheles species. Emphasis was placed on the primary vectors that have been epidemiologically incriminated in malaria transmission: Anopheles darlingi, Anopheles albimanus and Anopheles nuneztovari. The role of a selection of local, regional or secondary vectors (e.g., Anopheles pseudopunctipennis and Anopheles neivai is also discussed. We highlight the importance of combining biological, morphological and molecular data for the correct taxonomical determination of a given species, particularly for members of the species complexes. We likewise emphasise the importance of studying the bionomics of primary and secondary vectors along with an examination of the local conditions affecting the transmission of malaria. The presence and spread of the major vectors and the emergence of secondary species capable of transmitting human Plasmodia are of great interest. When selecting control measures, the anopheline diversity in the region must be considered. Variation in macroclimate conditions over a species' geographical range must be well understood and targeted to plan effective control measures based on the population dynamics of the local Anopheles species.

2D vector-cyclic deformable templates

DEFF Research Database (Denmark)

Schultz, Nette; Conradsen, Knut

1998-01-01

In this paper the theory of deformable templates is a vector cycle in 2D is described. The deformable template model originated in (Grenander, 1983) and was further investigated in (Grenander et al., 1991). A template vector distribution is induced by parameter distribution from transformation...... matrices applied to the vector cycle. An approximation in the parameter distribution is introduced. The main advantage by using the deformable template model is the ability to simulate a wide range of objects trained by e.g. their biological variations, and thereby improve restoration, segmentation...... and probabillity measurement. The case study concerns estimation of meat percent in pork carcasses. Given two cross-sectional images - one at the front and one near the ham of the carcass - the areas of lean and fat and a muscle in the lean area are measured automatically by the deformable templates....

Auto-tuning Dense Vector and Matrix-vector Operations for Fermi GPUs

DEFF Research Database (Denmark)

Sørensen, Hans Henrik Brandenborg

2012-01-01

applications. As examples, we develop single-precision CUDA kernels for the Euclidian norm (SNRM2) and the matrix-vector multiplication (SGEMV). The target hardware is the most recent Nvidia Tesla 20-series (Fermi architecture). We show that auto-tuning can be successfully applied to achieve high performance...

Tagged Vector Contour (TVC)

Data.gov (United States)

Kansas Data Access and Support Center — The Kansas Tagged Vector Contour (TVC) dataset consists of digitized contours from the 7.5 minute topographic quadrangle maps. Coverage for the state is incomplete....

Stable solutions of inflation driven by vector fields

Energy Technology Data Exchange (ETDEWEB)

Emami, Razieh [Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong); Mukohyama, Shinji [Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University, 606-8502, Kyoto (Japan); Namba, Ryo [Department of Physics, McGill University, Montréal, QC, H3A 2T8 (Canada); Zhang, Ying-li, E-mail: iasraziehm@ust.hk, E-mail: shinji.mukohyama@yukawa.kyoto-u.ac.jp, E-mail: namba@physics.mcgill.ca, E-mail: yingli@bao.ac.cn [National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China)

2017-03-01

Many models of inflation driven by vector fields alone have been known to be plagued by pathological behaviors, namely ghost and/or gradient instabilities. In this work, we seek a new class of vector-driven inflationary models that evade all of the mentioned instabilities. We build our analysis on the Generalized Proca Theory with an extension to three vector fields to realize isotropic expansion. We obtain the conditions required for quasi de-Sitter solutions to be an attractor analogous to the standard slow-roll one and those for their stability at the level of linearized perturbations. Identifying the remedy to the existing unstable models, we provide a simple example and explicitly show its stability. This significantly broadens our knowledge on vector inflationary scenarios, reviving potential phenomenological interests for this class of models.

Stable solutions of inflation driven by vector fields

International Nuclear Information System (INIS)

Emami, Razieh; Mukohyama, Shinji; Namba, Ryo; Zhang, Ying-li

2017-01-01

Many models of inflation driven by vector fields alone have been known to be plagued by pathological behaviors, namely ghost and/or gradient instabilities. In this work, we seek a new class of vector-driven inflationary models that evade all of the mentioned instabilities. We build our analysis on the Generalized Proca Theory with an extension to three vector fields to realize isotropic expansion. We obtain the conditions required for quasi de-Sitter solutions to be an attractor analogous to the standard slow-roll one and those for their stability at the level of linearized perturbations. Identifying the remedy to the existing unstable models, we provide a simple example and explicitly show its stability. This significantly broadens our knowledge on vector inflationary scenarios, reviving potential phenomenological interests for this class of models.

Light Higgs and vector-like quarks without prejudice

Science.gov (United States)

Fajfer, Svjetlana; Greljo, Admir; Kamenik, Jernej F.; Mustać, Ivana

2013-07-01

Light vector-like quarks with non-renormalizable couplings to the Higgs are a common feature of models trying to address the electroweak (EW) hierarchy problem by treating the Higgs as a pseudo-goldstone boson of a global (approximate) symmetry. We systematically investigate the implications of the leading dimension five operators on Higgs phenomenology in presence of dynamical up- and down-type weak singlet as well as weak doublet vector-like quarks. After taking into account constraints from precision EW and flavour observables we show that contrary to the renormalizable models, significant modifications of Higgs properties are still possible and could shed light on the role of vector-like quarks in solutions to the EW hierarchy problem. We also briefly discuss implications of higher dimensional operators for direct vector-like quark searches at the LHC.

Speech Data Compression using Vector Quantization

OpenAIRE

H. B. Kekre; Tanuja K. Sarode

2008-01-01

Mostly transforms are used for speech data compressions which are lossy algorithms. Such algorithms are tolerable for speech data compression since the loss in quality is not perceived by the human ear. However the vector quantization (VQ) has a potential to give more data compression maintaining the same quality. In this paper we propose speech data compression algorithm using vector quantization technique. We have used VQ algorithms LBG, KPE and FCG. The results table s...

Maxwell's Multipole Vectors and the CMB

OpenAIRE

Weeks, Jeffrey R.

2004-01-01

The recently re-discovered multipole vector approach to understanding the harmonic decomposition of the cosmic microwave background traces its roots to Maxwell's Treatise on Electricity and Magnetism. Taking Maxwell's directional derivative approach as a starting point, the present article develops a fast algorithm for computing multipole vectors, with an exposition that is both simpler and better motivated than in the author's previous work. Tests show the resulting algorithm, coded up as a ...

Vector condensate model of electroweak interactions

International Nuclear Information System (INIS)

Cynolter, G.; Pocsik, G.

1997-01-01

Motivated by the fact that the Higgs is not seen, a new version of the standard model is proposed where the scalar doublet is replaced by a vector doublet and its neutral member forms a nonvanishing condensate. Gauge fields are coupled to the new vector fields B in a gauge invariant way leading to mass terms for the gauge fields by condensation. The model is presented and some implications are discussed. (K.A.)

A novel prokaryotic vector for identification and selection of recombinants: Direct use of the vector for expression studies in E. coli

Directory of Open Access Journals (Sweden)

Apte-Deshpande Anjali

2010-05-01

Full Text Available Abstract Background The selection of bacterial recombinants that harbour a desired insert, has been a key factor in molecular cloning and a series of screening procedures need to be performed for selection of clones carrying the genes of interest. The conventional cloning techniques are reported to have problems such as screening high number of colonies, generation of false positives, setting up of control ligation mix with vector alone etc. Results We describe the development of a novel dual cloning/expression vector, which enables to screen the recombinants directly and expression of the gene of interest. The vector contains Green fluorescence protein (GFP as the reporter gene and is constructed in such a way that the E. coli cells upon transformation with this vector does not show any fluorescence, but readily fluoresce upon insertion of a foreign gene of interest. The same construct could be easily used for screening of the clones and expression studies by mere switching to specific hosts. Conclusions This is the first vector reported that takes the property of colour or fluorescence to be achieved only upon cloning while all the other vectors available commercially show loss of colour or loss of fluorescence upon cloning. As the fluorescence of GFP depends on the solubility of the protein, the intensity of the fluorescence would also indicate the extent of solubility of the expressed target protein.

Traditional and robust vector selection methods for use with similarity based models

International Nuclear Information System (INIS)

Hines, J. W.; Garvey, D. R.

2006-01-01

Vector selection, or instance selection as it is often called in the data mining literature, performs a critical task in the development of nonparametric, similarity based models. Nonparametric, similarity based modeling (SBM) is a form of 'lazy learning' which constructs a local model 'on the fly' by comparing a query vector to historical, training vectors. For large training sets the creation of local models may become cumbersome, since each training vector must be compared to the query vector. To alleviate this computational burden, varying forms of training vector sampling may be employed with the goal of selecting a subset of the training data such that the samples are representative of the underlying process. This paper describes one such SBM, namely auto-associative kernel regression (AAKR), and presents five traditional vector selection methods and one robust vector selection method that may be used to select prototype vectors from a larger data set in model training. The five traditional vector selection methods considered are min-max, vector ordering, combination min-max and vector ordering, fuzzy c-means clustering, and Adeli-Hung clustering. Each method is described in detail and compared using artificially generated data and data collected from the steam system of an operating nuclear power plant. (authors)

Generation of arbitrary vector beams

Science.gov (United States)

Perez-Garcia, Benjamin; López-Mariscal, Carlos; Hernandez-Aranda, Raul I.; Gutiérrez-Vega, Julio C.

2017-08-01

Optical vector beams arise from point to point spatial variations of the electric component of an electromagnetic field over the transverse plane. In this work, we present a novel experimental technique to generate arbitrary vec- tor beams, and provide sufficient evidence to validate their state of polarization. This technique takes advantage of the capability of a Spatial Light Modulator to simultaneously generate two components of an electromagnetic field by halving the screen of the device and subsequently recombining them in a Sagnac interferometer. Our experimental results show the versatility and robustness of this technique for the generation of vector beams.

Vector-borne Infections

Centers for Disease Control (CDC) Podcasts

2011-04-18

This podcast discusses emerging vector-borne pathogens, their role as prominent contributors to emerging infectious diseases, how they're spread, and the ineffectiveness of mosquito control methods.  Created: 4/18/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/27/2011.

An improved ternary vector system for Agrobacterium-mediated rapid maize transformation.

Science.gov (United States)

Anand, Ajith; Bass, Steven H; Wu, Emily; Wang, Ning; McBride, Kevin E; Annaluru, Narayana; Miller, Michael; Hua, Mo; Jones, Todd J

2018-05-01

A simple and versatile ternary vector system that utilizes improved accessory plasmids for rapid maize transformation is described. This system facilitates high-throughput vector construction and plant transformation. The super binary plasmid pSB1 is a mainstay of maize transformation. However, the large size of the base vector makes it challenging to clone, the process of co-integration is cumbersome and inefficient, and some Agrobacterium strains are known to give rise to spontaneous mutants resistant to tetracycline. These limitations present substantial barriers to high throughput vector construction. Here we describe a smaller, simpler and versatile ternary vector system for maize transformation that utilizes improved accessory plasmids requiring no co-integration step. In addition, the newly described accessory plasmids have restored virulence genes found to be defective in pSB1, as well as added virulence genes. Testing of different configurations of the accessory plasmids in combination with T-DNA binary vector as ternary vectors nearly doubles both the raw transformation frequency and the number of transformation events of usable quality in difficult-to-transform maize inbreds. The newly described ternary vectors enabled the development of a rapid maize transformation method for elite inbreds. This vector system facilitated screening different origins of replication on the accessory plasmid and T-DNA vector, and four combinations were identified that have high (86-103%) raw transformation frequency in an elite maize inbred.

Limit theorems for functionals of Gaussian vectors

Institute of Scientific and Technical Information of China (English)

Hongshuai DAI; Guangjun SHEN; Lingtao KONG

2017-01-01

Operator self-similar processes,as an extension of self-similar processes,have been studied extensively.In this work,we study limit theorems for functionals of Gaussian vectors.Under some conditions,we determine that the limit of partial sums of functionals of a stationary Gaussian sequence of random vectors is an operator self-similar process.

Construction of expression vectors carrying mouse peroxisomal ...

African Journals Online (AJOL)

PRECIOUS

2009-11-16

Nov 16, 2009 ... The aim of this study was to construct expression vectors carrying mouse peroxisomal protein gene. (PEP-cDNA) in prokaryotic and mammalian expression vectors in chimeric cDNA types, encompassing. GST and FLAG with PEP-cDNA. PEP-cDNA was sub-cloned in pGEX6p2 prokaryotic expression ...

Developing clones of Eucalyptus cloeziana resistant to rust (Puccinia psidii)

Science.gov (United States)

Rafael F. Alfenas; Marcelo M. Coutinho; Camila S. Freitas; Rodrigo G. Freitas; Acelino C. Alfenas