Página 1 dos resultados de 1818 itens digitais encontrados em 0.004 segundos

Analysis of the association of an MMP1 promoter polymorphism and transcript levels with chronic periodontitis and end-stage renal disease in a Brazilian population

Luczyszyn, Sonia M.; Souza, Cleber M. de; Braosi, Ana P. R.; Dirschnabel, Acir J.; Claudino, Marcela; Repeke, Carlos E.; Faucz, Fabio R.; Garlet, Gustavo P.; Pecoits-Filho, Roberto; Trevilatto, Paula C.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.88%
Chronic periodontitis (CP) and end-stage renal disease (ESRD) are complex inflammatory conditions. Higher levels of MMP-1 were found in fluids and gingival tissues from CP patients and in the blood and tissues from ESRD patients. MMP1-1607 (1G/2G) is a functional polymorphism, as it alters MMP-1 expression. Objective: The aim of this study was to investigate the association of the MMP1-1607 (1G/2G) polymorphism with CP and ESRD and evaluate differences in transcript levels between the groups. Design: A total of 254 individuals were divided into four groups: Group 1, without CP and without chronic kidney disease (CKD) (n = 67); Group 2, with CP and without CKD (n = 60); Group 3, without CP and with CKD stages (ESRD) (n = 52), and Group 4, with CP and with ESRD (n = 75). The MMP1-1607 polymorphism was analysed by PCR-RFLP. MMP1 gene transcripts from gingival tissues were analysed by real-time PCR. Results: No association was found between the MMP1-1607 polymorphism and CP or ESRD. Increased levels of MMP1 transcripts were observed in CP patients with or without ESRD. No differences were observed in the transcript levels according to the genotypes. Conclusion: It was concluded that the MMP1-1607 polymorphism was not associated with either CP or ESRD. However...

Determinação e caracterização físico-química e espectroscópica de gramíneas para obtenção de etanol de segunda geração; Determination and physico-chemical and spectroscopic characterization grasses to obtain second-generation ethanol

Martelli, Fabricio Heitor
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/02/2015 Português
Relevância na Pesquisa
27.03%
A busca por combustíveis renováveis tem se expandido cada vez mais no mundo moderno, devido à preocupação com a redução do volume de emissões de gases causadores do efeito estufa. No presente trabalho descreve-se a caracterização físico-quíca e espectroscópica de gramíneas com potencial para geração de Etanol 2G (Sorgo Biomassa, Capim Elefante, Capim Marandu, Capim Mombaça). As matrizes vegetais foram caracterizadas por diferentes técnicas, incluindo Análise Elementar, Ressonância Magnética Nuclear (RMN) de 13C, difração de raios X (DR-X), espectroscopia de infravermelho com transformada de Fourrier (FTIR), microscopia eletrônica de varredura acoplada com detector de energia dispersiva (MEV-EDS). Os componentes extraídos foram avaliados por cromatografia líquida de alta eficiência (CLAE) e por espectroscopia de absorção eletrônica (UV-VIS). O bagaço de cana apresentou maior teor de C com 45,0%, o colmo do Capim-Marandu apresentou maior concentração de O com 46,1%; a concentração de H para todos os materiais ficaram próximas dos 5%; as folhas do Capim-Marandu apresentaram 4,5% de teor de S; as folhas de Capim-Elefante e do Sorgo apresentaram maior concentração de N que tiveram como média 2%. As análises da composição lignocelulósica por via ácida diluída mostraram que os colmos possuem maior concentração de celulose...

Analise de desempenho dos sistemas moveis celulares 2G, 2,5G e 3G; Performance analysis of 2G, 2.5G and 3G cellular mobile systems

Carlos Henrique Rodrigues de Oliveira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 12/08/2005 Português
Relevância na Pesquisa
27.03%
Este trabalho de tese estuda e analisa o desempenho dos sistemas móveis celulares GSM de segunda geração (2G), GPRS de segunda geração intermediária (2,5G) e CDMA2000 de terceira geração (3G). Na primeira parte deste trabalho de tese são avaliadas estratégias de compartilhamento dos canais de comunicação utilizados pelos sistemas GSM e GPRS, em busca daquela que resulte no menor impacto na qualidade dos serviços prestados por ambas as redes. Para esta avaliação, e como contribuição deste trabalho de tese, são desenvolvidos algoritmos aplicados em um simulador de eventos discretos desenvolvido em linguagem de programação C/C++. Os resultados das simulações mostram que a reserva de canais exclusivos ao sistema GPRS apresenta degradação na qualidade de serviço prestado pelo sistema GSM e que a melhor estratégia de compartilhamento é utilizar os canais de comunicação para o sistema GPRS nos momentos em que estes canais não são usados pelo sistema GSM. Na segunda parte deste trabalho de tese são feitas análises de desempenho dos sistemas móveis celulares de terceira geração, CDMA2000 lxRTT e CDMA2000 lxEVDO, baseadas na qualidade do serviço prestado por estas redes operando com várias aplicações simultâneas fim-a-fim entre cliente e servidor. Técnicas de detecção multiusuário e de antenas adaptativas são utilizadas na recepção destas aplicações e é avaliada a nova qualidade de serviço. Para estas análises de desempenho e como contribuição deste trabalho de tese...

Persistence of Vectobac WDG and Metoprag S-2G against Aedes aegypti larvae using a semi-field bioassay in Rio de Janeiro, Brazil

Lima,José Bento Pereira; Melo,Nilson Vieira de; Valle,Denise
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2005 Português
Relevância na Pesquisa
27.03%
Persistence of Bacillus thuringiensis var. israelensis (Vectobac WDG) and methoprene (Metoprag S-2G) was evaluated against Aedes aegypti late third instar larvae of the Rockefeller strain in a semi-field bioassay. Tests were performed in Rio de Janeiro, using containers made of plastic, iron, concrete and asbestos, placed in a shaded area. The formulations used were 0.2 g of Vectobac-WDG and 1g of Metoprag S-2G per 100 liters of water in house storage containers. Vectobac WDG was tested twice, in March and in April/May, 2002. In March (temperature ranging from 21.5 to 39.3 ºC), 70-100% mortality was observed by the 7th day and declined abruptly thereafter. No significant differences were observed among the container types. In April/May (18.6 to 34.8 ºC) mortality was higher than 70% to 30-36 days in all cases, except in the iron container (40% mortality on the 12th day). Metoprag S-2G was evaluated in April/May, 2002, and induced mortality higher than 70% up to 15 days in the plastic and iron containers and only seven days in the concrete container. In the asbestos container, maximal mortality was achieved on day one post-treatment (66%). Our results point to a low persistence of both formulations in the weather conditions of Rio de Janeiro.

The products from papain and pepsin hydrolyses of guinea-pig immunoglobulins γ1G and γ2G

Leslie, R. G. Q.; Melamed, M. D.; Cohen, S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1971 Português
Relevância na Pesquisa
27.2%
1. The products from papain and pepsin hydrolyses of the guinea-pig immunoglobulins γ1G and γ2G were isolated and characterized with regard to molecular weight, amino acid composition, hexose content and antigenic specificity. 2. Fragments Fab and (Fab′)2 from immunoglobulins γ1G and γ2G have similar electrophoretic and antigenic properties, but show some class-specific differences in amino acid composition. 3. Three Fc fragments were obtained after papain digestion of immunoglobulin γ2G, namely, fragment Fc dimer (mol.wt. 58000), fragment Fc monomer (mol.wt. 29000) and fragment Fc′ (mol.wt. 8000). A single crystalline fragment, namely fragment Fc′ (mol.wt. 11000), was isolated after papain digestion of immunoglobulin γ1G. 4. Peptic digestion of immunoglobulins γ1G and γ2G releases C-terminal fragments, namely, fragments pFc′, of similar molecular weight (13000) but different amino acid compositions and distinct antigenic specificities. 5. Digestion-time studies show that immunoglobulin γ1G is far more susceptible to proteolysis than is immunoglobulin γ2G and suggest that at least a proportion of molecules are split primarily at a site that liberates fragment γ1Fc′.

The collagenase-1 (MMP-1) gene promoter polymorphism - 1607/2G is associated with favourable prognosis in patients with colorectal cancer

Hettiaratchi, A; Hawkins, N J; McKenzie, G; Ward, R L; Hunt, J E; Wakefield, D; Di Girolamo, N
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.13%
Matrix metalloproteinase (MMP) overexpression has been implicated in the pathogenesis of colorectal carcinoma (CRC). Accumulating evidence suggests that MMP promoter single nucleotide polymorphisms (SNPs) effecting gene transcription are associated with enhanced susceptibility for the development of malignant disease, increased tumour invasiveness and poor patient survival. The aim of the current investigation was to determine whether such associations exist in a large CRC patient/control study population. Using an allelic discrimination real-time polymerase chain reaction, polymorphisms in the MMP-1, MMP-2 and MMP-3 gene promoters (−1607, −1306, and −1612 bp, respectively) were assessed in normal blood mononuclear cells from patients with CRC (n=503) and control subjects (n=471). Genotypes corresponding to each MMP SNP were correlated with tumour characteristics and clinical outcome. The frequency of each genotype was not statistically different between patients and control subjects and no significant differences were noted between the genotypes and tumour characteristics for the three MMP SNPs. CRC patients with the 2G/2G genotype for the MMP-1 SNP had significantly better 5-year survival compared to patients with a 1G allele (P<0.05). Our results demonstrate that CRC patients with a 2G/2G genotype in the MMP-1 gene promoter SNP have a favourable prognosis. Although our results were unexpected...

Joint Effect of MCP-1 Genotype GG and MMP-1 Genotype 2G/2G Increases the Likelihood of Developing Pulmonary Tuberculosis in BCG-Vaccinated Individuals

Ganachari, Malathesha; Ruiz-Morales, Jorge A.; Gomez de la Torre Pretell, Juan C.; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 25/01/2010 Português
Relevância na Pesquisa
27.2%
We previously reported that the – 2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the – 1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the – 2518 MCP-1 genotype GG and the – 1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1...

Security Enhancement Mechanism Based on Contextual Authentication and Role Analysis for 2G-RFID Systems

Tang, Wan; Chen, Min; Ni, Jin; Yang, Ximin
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 28/06/2011 Português
Relevância na Pesquisa
27.13%
The traditional Radio Frequency Identification (RFID) system, in which the information maintained in tags is passive and static, has no intelligent decision-making ability to suit application and environment dynamics. The Second-Generation RFID (2G-RFID) system, referred as 2G-RFID-sys, is an evolution of the traditional RFID system to ensure better quality of service in future networks. Due to the openness of the active mobile codes in the 2G-RFID system, the realization of conveying intelligence brings a critical issue: how can we make sure the backend system will interpret and execute mobile codes in the right way without misuse so as to avoid malicious attacks? To address this issue, this paper expands the concept of Role-Based Access Control (RBAC) by introducing context-aware computing, and then designs a secure middleware for backend systems, named Two-Level Security Enhancement Mechanism or 2L-SEM, in order to ensure the usability and validity of the mobile code through contextual authentication and role analysis. According to the given contextual restrictions, 2L-SEM can filtrate the illegal and invalid mobile codes contained in tags. Finally, a reference architecture and its typical application are given to illustrate the implementation of 2L-SEM in a 2G-RFID system...

MD simulation studies to investigate iso-energetic conformational behaviour of modified nucleosides m2G and m2 2G present in tRNA

Bavi, Rohit S; Sambhare, Susmit B; Sonawane, Kailas D
Fonte: Research Network of Computational and Structural Biotechnology (RNCSB) Organization Publicador: Research Network of Computational and Structural Biotechnology (RNCSB) Organization
Tipo: Artigo de Revista Científica
Publicado em 08/06/2013 Português
Relevância na Pesquisa
27.03%
Modified nucleic acid bases are most commonly found in tRNA. These may contain modifications from simple methylation to addition of bulky groups. Methylation of the four canonical nucleotide bases at a wide variety of positions is particularly prominent among the known modification. Methylation of N2 group of guanine is a relatively common modification in tRNA and rRNA. N2-methylguanosine (m2G) is the second most often encountered nucleoside in E. coli tRNAs. N2, N2- dimethylguanosine (m2 2G) is found in the majority of eukaryotic tRNAs and involved in forming base pair interactions with adjacent bases. Hence, in order to understand the structural significance of these methylated nucleic acid bases we have carried out molecular dynamics simulation to see the salvation effect. The results obtained shows iso-energetic conformational behaviors for m2G and m2 2G. The simulation trajectory of m2G shows regular periodical fluctuations suggesting that m2G is equally stable as either s-cis or s-trans rotamers. The two rotamers of m2G may interact canonically or non-canonically with opposite base as s-trans m2G26:C/A/U44 and s-cis m2G26:A/U44. The free rotations around the C-N bond could be the possible reason for these iso-energetic conformations. Dimethylation of G has almost no influence on base pairing with either A or U. Thus...

Association between matrix metalloproteinase 1 -1607 1G>2G polymorphism and cancer risk: a meta-analysis including 19706 subjects

Han, Guoda; Wei, Zhijiang; Lu, Zhiliang; Cui, Haibin; Bai, Xiyong; Ge, Huai’e; Zhang, Wei
Fonte: e-Century Publishing Corporation Publicador: e-Century Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 15/09/2014 Português
Relevância na Pesquisa
27.2%
The association between MMP1 -1607 1G>2G polymorphism and cancer risk has been reported, but results remained controversial and ambiguous. To assess the association between MMP1 -1607 1G>2G polymorphism and cancer risk, a meta-analysis was performed. Based on comprehensive searches of the PubMed, Elsevier Science Direct, Excerpta Medica Database (Embase), and Chinese Biomedical Literature Database (CBM), we identified outcome data from all articles estimating the association between MMP1 -1607 1G>2G polymorphism and cancer risk. The pooled odds ratio (OR) with 95% confidence intervals (CIs) were calculated. Thirty-eight studies involving 10178 cases and 9528 controls were included. Overall, significant association between MMP1 -1607 1G>2G polymorphism and cancer susceptibility was observed for additive model (OR = 1.21, 95% CI 1.09-1.35), for codominant model (OR = 1.34, 95% CI 1.10-1.63), for dominant model (OR = 1.17, 95% CI 1.01-1.34), for recessive model (OR = 1.31, 95% CI 1.14-1.52). In the subgroup analysis by ethnicity, the significant association was found among Asians but not among Caucasians. In the subgroup analysis by site of cancer, significant associations were found among lung cancer, colorectal cancer, head and neck cancer and bladder cancer. This meta-analysis demonstrated that the MMP1 -1607 1G>2G polymorphism was significantly associated with cancer risk.

Diseño de una red móvil 2G-3G en la Península Ibérica - España; Design of a 2G-3G mobile in the Iberian Peninsula - Spain

Pérez Jaimes, Martín
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
37.53%
RESUMEN: El propósito de este proyecto es la creación de un conjunto de datos requeridos para el diseño de una red móvil red móvil 2G-3G con aplicaciones en la península ibérica en España. Para ello se determinan diferentes escenarios a través de la creación de códigos postales que se subdividen en áreas correspondientes a urbana, suburbana y rural. En este diseño se establece una metodología propia de una red móvil en la implementación de celdas 2G-3G así como la red de agregación, red backhaul y la red dorsal. Este proyecto se concentra al despliegue celular porque tiene el objetivo demostrar la ventaja de la implementación de tecnología 3G frente a la tecnología 2G. Inicialmente se establecen unos datos de entrada propias para un modelo de red 2G, 3G como la arquitectura, datos topográficos, servicios y trafico. Una vez definidos estos criterios se genera los escenarios de simulación propias del modelo a través de una herramienta existente (2G-3G Connect) desarrollada por el grupo de telemática de la universidad de Cantabria y la Universidad de Alcalá. Para el despliegue se consideran tres tipos de sititos (Sites) en la instalación de estaciones básicas, 2G, 3G e hibrido (2G-3G) y tres tipos de áreas en relación con su densidad de población (urbano...

Characterisation of noisy speech channels in 2G and 3G mobile networks

Leite, Bruno Daniel Moreira
Fonte: Instituto Politécnico do Porto Publicador: Instituto Politécnico do Porto
Tipo: Dissertação de Mestrado
Publicado em //2013 Português
Relevância na Pesquisa
37.25%
As the wireless cellular market reaches competitive levels never seen before, network operators need to focus on maintaining Quality of Service (QoS) a main priority if they wish to attract new subscribers while keeping existing customers satisfied. Speech Quality as perceived by the end user is one major example of a characteristic in constant need of maintenance and improvement. It is in this topic that this Master Thesis project fits in. Making use of an intrusive method of speech quality evaluation, as a means to further study and characterize the performance of speech codecs in second-generation (2G) and third-generation (3G) technologies. Trying to find further correlation between codecs with similar bit rates, along with the exploration of certain transmission parameters which may aid in the assessment of speech quality. Due to some limitations concerning the audio analyzer equipment that was to be employed, a different system for recording the test samples was sought out. Although the new designed system is not standard, after extensive testing and optimization of the system's parameters, final results were found reliable and satisfactory. Tests include a set of high and low bit rate codecs for both 2G and 3G, where values were compared and analysed...

A Low-complexity Channel Shortening Receiver with Diversity Support for Evolved 2G Device

Hu, Sha; Kroll, Harald; Huang, Qiuting; Rusek, Fredrik
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/11/2015 Português
Relevância na Pesquisa
27.03%
The second generation (2G) cellular networks are the current workhorse for machine-to-machine (M2M) communications. Diversity in 2G devices can be present both in form of multiple receive branches and blind repetitions. In presence of diversity, intersymbol interference (ISI) equalization and co-channel interference (CCI) suppression are usually very complex. In this paper, we consider the improvements for 2G devices with receive diversity. We derive a low-complexity receiver based on a channel shortening filter, which allows to sum up all diversity branches to a single stream after filtering while keeping the full diversity gain. The summed up stream is subsequently processed by a single stream Max-log-MAP (MLM) equalizer. The channel shortening filter is designed to maximize the mutual information lower bound (MILB) with the Ungerboeck detection model. Its filter coefficients can be obtained mainly by means of discrete-Fourier transforms (DFTs). Compared with the state-of-art homomorphic (HOM) filtering based channel shortener which cooperates with a delayed-decision feedback MLM (DDF-MLM) equalizer, the proposed MILB channel shortener has superior performance. Moreover, the equalization complexity, in terms of real-valued multiplications...

Siegel Modular Varieties and the Eisenstein Cohomology of $\PGL_{2g+1}$

Weselmann, Uwe
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.13%
We use the twisted topological trace formula developed in an earlier paper to understand liftings from symplectic to general linear groups. We analyse the lift from $\SP_{2g}$ to $\PGL_{2g+1}$ over the ground field $\Q$ in further detail, and we get a description of the image of this lift for the $L^2$ cohomology of $\SP_{2g}$ (which is related to the intersection cohomology of the Shimura variety attached to $\GSp_{2g}$) in terms of the Eisenstein cohomology of the general linear group, whose building constituents are cuspidal representations of Levi groups. This description may be used to understand endoscopic and CAP-representations of the symplectic group.; Comment: 52 pages

3-D modeling and simulation of 2G HTS stacks and coils

Zermeño, Victor M. R.; Grilli, Francesco
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.03%
Use of 2G HTS coated conductors in several power applications has become popular in recent years. Their large current density under high magnetic fields makes them suitable candidates for high power capacity applications such as stacks, coils, magnets, cables and current leads. For this reason, modeling and simulation of their electromagnetic properties is very desirable in the design and optimization processes. For many applications, when symmetries allow it, simple models consisting of 1D or 2D representations are well suited for providing a satisfying description of the problem at hand. However, certain designs such as racetrack coils and finite-length or non-straight stacks, do pose a 3D problem that cannot be easily reduced to a 2D configuration. Full 3-D models have been developed, but their use for simulating superconducting devices is a very challenging task involving a large-scale computational problem. In this work, we present a new method to simulate the electromagnetic transient behavior of 2G HTS stacks and coils. The method, originally used to model stacks of straight superconducting tapes or circular coils in 2D, is now extended to 3D. The main idea is to construct an anisotropic bulklike equivalent for the stack or coil...

The crucial importance of the $t_{2g}$--$e_g$ hybridization in transition metal oxides

Landron, Sylvain; Lepetit, Marie-Bernadette
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.03%
We studied the influence of the trigonal distortion of the regular octahedron along the (111) direction, found in the $\rm CoO_2$ layers. Under such a distortion the $t_{2g}$ orbitals split into one $a_{1g}$ and two degenerated $e_g^\prime$ orbitals. We focused on the relative order of these orbitals. Using quantum chemical calculations of embedded clusters at different levels of theory, we analyzed the influence of the different effects not taken into account in the crystalline field theory; that is metal-ligand hybridization, long-range crystalline field, screening effects and orbital relaxation. We found that none of them are responsible for the relative order of the $t_{2g}$ orbitals. In fact, the trigonal distortion allows a mixing of the $t_{2g}$ and $e_g$ orbitals of the metallic atom. This hybridization is at the origin of the $a_{1g}$--$e_g^\prime$ relative order and of the incorrect prediction of the crystalline field theory.

On an action of the braid group B_{2g+2} on the free group F_{2g}

Kassel, Christian
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.2%
We construct an action of the braid group B_{2g+2} on the free group F_{2g} extending an action of B_4 on F_2 introduced earlier by Reutenauer and the author. Our action induces a homomorphism from B_{2g+2} into the symplectic modular group Sp_{2g}(Z). In the special case g=2 we show that the latter homomorphism is surjective and determine its kernel, thus obtaining a braid-like presentation of Sp_4(Z).; Comment: 11 pages. Minor changes in v2

A note on actions of the symplectic group Sp(2g,Z) on homology spheres

Zimmermann, Bruno P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/03/2009 Português
Relevância na Pesquisa
27.25%
The symplectic group Sp(2g,Z) is a subgroup of the linear group SL(2g,Z) and admits a faithful action on the sphere S^(2g-1), induced from its linear action on Euclidean space R^(2g). Generalizing corresponding results for linear groups, we show that, if m < 2g-1 and g > 2, any continuous action of Sp(2g,Z) on a homology m-sphere, and in particular on S^m, is trivial.; Comment: 6 pages

Experimental Study of the Normal Zone Propagation Velocity in Double-layer 2G-HTS wires by Thermal and Electrical Methods

Zhong, Z.; Ruiz, H. S.; Lai, L.; Huang, Z.; Wang, W.; Coombs, T.
Fonte: IEEE Publicador: IEEE
Tipo: Article; accepted version
Português
Relevância na Pesquisa
36.88%
This is the accepted manuscript. The final version is available from IEEE at http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6963291&sortType%3Dasc_p_Sequence%26filter%3DAND%28p_IS_Number%3A6353170%29%26rowsPerPage%3D50.; The Normal Zone Propagation Velocity (NZPV) of a double-layer second generation (2G) high temperature superconducting (HTS) wire manufactured by American Superconductor has been measured by electrical and thermal methods, and the results have been compared and discussed. The NZPV values determined by the voltage traces are ranging from 3.8 mm/s at 0.4 Ic to 19.2 mm/s at 0.9 Ic; while from 5.9 mm/s to 18.3 mm/s by the temperature traces. NZPV determined by these two approaches agrees well with each other. Also, NZPV of double-layer YBCO tape is close to that of conventional single-layer superconducting tape.; This work was supported in part by the EPSRC under Grant NMZF/064.

Persistência de Vectobac WDG e Metoprag S-2g contra larvas de Aedes aegypti em ensaio simulado de campo no Rio de Janeiro, Brasil; Persistence of Vectobac WDG and Metoprag S-2G against Aedes aegypti larvae using a semi-field bioassay in Rio de Janeiro, Brazil

Lima, José Bento Pereira; Melo, Nilson Vieira de; Valle, Denise
Fonte: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo Publicador: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/02/2005 Português
Relevância na Pesquisa
27.33%
A persistência de Bacillus thuringiensis var. israelensis (Vectobac WDG) e de Metoprene (Metoprag S-2G) contra larvas de terceiro estadio de Aedes aegypti (linhagem Rockefeller) foi avaliada em ensaios simulados de campo. Os testes foram realizados no Rio de Janeiro, em recipientes domésticos para estoque de água de plástico, ferro, cimento ou amianto, instalados em área sombreada. As formulações foram usadas nas concentrações de 0.2g / 100 l (Vectobac-WDG) e 1g / 100 l (Metoprag S-2G). Vectobac WDG foi submetido a dois testes, em março e abril/maio, 2002. Em março (temperaturas entre 21.5 e 39.3 ºC), 70-100% de mortalidade foi observada no sétimo dia, declinando posteriormente. Não houve diferença significativa entre os recipientes. Em abril / maio (18.6 a 34.8 ºC) a mortalidade foi superior a 70% até 30-36 dias em todos os casos, exceto no recipiente de ferro (40% de mortalidade no 12° dia). Metoprag S-2G, avaliado em abril / maio, 2002, induziu mortalidade acima de 70% durante 15 dias nos recipientes de plástico e de ferro e por apenas sete dias naquele de cimento. No recipiente de amianto, nunca se atingiu 70% de mortalidade. Estes resultados apontam para uma baixa persistência de ambas formulações nas condições climáticas do Rio de Janeiro.; Persistence of Bacillus thuringiensis var. israelensis (Vectobac WDG) and methoprene (Metoprag S-2G) was evaluated against Aedes aegypti late third instar larvae of the Rockefeller strain in a semi-field bioassay. Tests were performed in Rio de Janeiro...