267 resultados para Vector failure rate


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Background: Although the influence of respiration on ventricular filling, as evaluated by Doppler technique, and the evaluation of diastolic velocities of mitral valve annulus (MVA), as measured by Doppler tissue imaging (DTI), can provide valuable information for the study of left ventricular (LV) diastolic function, the concomitant effects of aging, tidal volume (TV), and respiratory rate (RR) on these velocities have not been quantitatively investigated. Methods: We evaluated 12 normal male volunteers (Group I) aged 20-26 years (mean: 22.8) and 8 normal subjects aged 41 to 54 years old (mean: 45.9) (Group II). Using DTI we measured peak early (E-a) and late (A(a)) velocities of longitudinal axis expansion at lateral and medial MVA. Doppler mitral and tricuspid flow velocities were measured: peak early (E) and late (A) inflow velocity, early (E-i) and late (A(i)) flow integral, and deceleration time of peak early mitral flow velocity (DT). Respiratory cycles were simultaneously recorded at RR of 9, 12, 15, and 18 cycles/min and TV of 600 and 900 mL during respiration (RESP). Results and conclusions: (1) E, A, and A(i) in MV had negligible change during respiration, but E-i was significantly reduced during inspiration; (2) DT reduced slightly with inspiration, but the change was significant only with TV of 900 mL; (3) an important increase of E in right ventricular flow was observed during inspiration; (4) variations of RR and TV did not significantly influence right and left ventricular inflow in normal subjects, in the conditions of this investigation; (5) a significant increase of E-a at medial MVA was documented during inspiration only in young subjects; (6) a significant decrease of A(a) at medial MVA was observed during inspiration in both groups of volunteers; (7) RR and TV did not influence MVA velocities in young and adult subjects; (8) a consistent reduction in E-a and a significant increase in A(a) were observed with increasing age; (9) these changes were more conspicuous and consistent than those documented in ventricular filling when young and middle-age men are compared, suggesting that the DTI is more sensitive to detect changes in diastolic function; and (10) in addition, these data suggest that, for evaluation of diastolic function, in clinical context, it is not necessary to control rigorously RR or TV.

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Objective. This study evaluated the degree of conversion (DC), maximum rate of cure (R(p)(max)), and polymerization stress (PS) developed by an experimental dental composite subjected to different irradiant energies (3,6,12, 24, or 48J/cm(2)) under constant irradiance (500 mw/cm(2)). Methods. DC and R(p)(max) were monitored for 10 min on the bottom surface of 2-mm thick disks and on 150-mu m thick films (representing the top of the specimen) using ATR-FTIR. PS was monitored for 10 min in 2-mm thick disks bonded to two glass rods (O = 5 mm) attached to a universal testing machine. One-way ANOVA/Tukey tests were used and differences in DC and R(p)(max) between top and bottom surfaces were examined using Student`s t-test. Statistical testing was performed at a pre-set alpha of 0.05. Results. For a given surface, DC showed differences among all groups, except at the top between 24 and 48 J/cm(2). R(p)(max) was similar among all groups at the same surface and statistically higher at the top surface. PS also showed significant differences among all groups. Data for 48 J/cm(2) were not obtained due to specimen failure at the glass/composite interface. Significance. Increases in irradiant exposure led to significant increases in DC and PS, but had no effect on R(p)(max) (c) 2008 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

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The study evaluated the in vitro influence of pulse-repetition rate of Er:YAG laser and dentin depth on tensile bond strength of dentin-resin interface. Dentin surfaces of buccal or lingual surfaces from human third molars were submitted to tensile test in different depths (superficial, 1.0 and 1.5 mm) of the same dental area, using the same sample. Surface treatments were acid conditioning solely (control) and Er:YAG laser irradiation (80 mJ) followed by acid conditioning, with different pulse-repetition rates (1, 2, 3, or 4 Hz). Single bond/Z-250 system was used. The samples were stored in distilled water at 37 degrees C for 24 h, and then the first test (superficial dentine) was performed. The bond failures were analyzed. Following, the specimens were identified, grounded until 1.0- and 1.5-mm depths, submitted again to the treatments and to the second and, after that, to third-bond tests on a similar procedure and failure analysis. ANOVA and Tukey test demonstrated a significant difference (p < 0.001) for treatment and treatment X depth interaction (p < 0.05). The tested depths did not show influence (p > 0.05) on the bond strength of dentin-resin interface. It may be concluded that Er:YAG laser with 1, 2, 3, or 4 Hz combined with acid conditioning did not increase the resin tensile bond strength to dentin, regardless of dentin depth. (C) 2007 Wiley Periodicals, Inc.

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Parity rate, gonotrophic cycle length, and density of a Culex quinquefasciatus female population was estimated at the Parque Ecologico do Tiete (PET), Sao Paulo, Brazil. Adult Cx. quinquefasciatus females were collected from vegetation along the edges of a polluted drainage canal with the use of a battery-powered backpack aspirator from September to November 2005 and from February to April 2006. We examined 255 Cx. quinquefasciatus ovaries to establish the parity rate of 0.22 and determined the gonotrophic cycle length under laboratory conditions to be 3 and 4 days. From these data, we calculated the Cx. quinquefasciatus survival rate to be 0.60 and 0.68 per day. Density of the Cx. quinquefasciatus female (5.71 females per m(2)) was estimated based on a population size of 28,810 individuals divided by the sampled area of 5,040 m(2). Results of all experiments indicate medium survivorship and high density of the Cx. quinquefasciatus female population. This species is epidemiologically relevant in the PET area and should be a target of the vector control program of Sao Paulo municipality.

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This paper proposes an improved voice activity detection (VAD) algorithm using wavelet and support vector machine (SVM) for European Telecommunication Standards Institution (ETS1) adaptive multi-rate (AMR) narrow-band (NB) and wide-band (WB) speech codecs. First, based on the wavelet transform, the original IIR filter bank and pitch/tone detector are implemented, respectively, via the wavelet filter bank and the wavelet-based pitch/tone detection algorithm. The wavelet filter bank can divide input speech signal into several frequency bands so that the signal power level at each sub-band can be calculated. In addition, the background noise level can be estimated in each sub-band by using the wavelet de-noising method. The wavelet filter bank is also derived to detect correlated complex signals like music. Then the proposed algorithm can apply SVM to train an optimized non-linear VAD decision rule involving the sub-band power, noise level, pitch period, tone flag, and complex signals warning flag of input speech signals. By the use of the trained SVM, the proposed VAD algorithm can produce more accurate detection results. Various experimental results carried out from the Aurora speech database with different noise conditions show that the proposed algorithm gives considerable VAD performances superior to the AMR-NB VAD Options 1 and 2, and AMR-WB VAD. (C) 2009 Elsevier Ltd. All rights reserved.

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In the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study ( n = 6632), eplerenone- associated reduction in all- cause mortality was significantly greater in those with a history of hypertension ( Hx- HTN). There were 4007 patients with Hx- HTN ( eplerenone: n = 1983) and 2625 patients without Hx- HTN ( eplerenone: n = 1336). Propensity scores for eplerenone use, separately calculated for patients with and without Hx- HTN, were used to assemble matched cohorts of 1838 and 1176 pairs of patients. In patients with Hx- HTN, all- cause mortality occurred in 18% of patients treated with placebo ( rate, 1430/ 10 000 person- years) and 14% of patients treated with eplerenone ( rate, 1058/ 10 000 person- years) during 2350 and 2457 years of follow- up, respectively ( hazard ratio [ HR]: 0.71; 95% CI: 0.59 to 0.85; P < 0.0001). Composite end point of cardiovascular hospitalization or cardiovascular mortality occurred in 33% of placebo-treated patients ( 3029/ 10 000 person- years) and 28% of eplerenone- treated patients (2438/10 000 person- years) with Hx- HTN ( HR: 0.82; 95% CI: 0.72 to 0.94; P = 0.003). In patients without Hx- HTN, eplerenone reduced heart failure hospitalization ( HR: 73; 95% CI: 0.55 to 0.97; P = 0.028) but had no effect on mortality ( HR: 0.91; 95% CI: 0.72 to 1.15; P = 0.435) or on the composite end point ( HR: 0.91; 95% CI: 0.76 to 1.10; P = 0.331). Eplerenone should, therefore, be prescribed to all of the post - acute myocardial infarction patients with reduced left ventricular ejection fraction and heart failure regardless of Hx- HTN.

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OBJETIVO: este estudo teve como objetivo avaliar a influência da largura do septo inter-radicular no local de inserção de mini-implantes autoperfurantes sobre o grau de estabilidade desses dispositivos de ancoragem. MÉTODOS: a amostra consistiu de 40 mini-implantes inseridos entre as raízes do primeiro molar e segundo pré-molar superiores de 21 pacientes, com o intuito de fornecer ancoragem para retração anterior. A largura do septo no local de inserção (LSI) foi mensurada nas radiografias pós-cirúrgicas e, sob esse aspecto, os mini-implantes foram divididos em dois grupos: grupo 1 (áreas críticas, LSI<3mm) e grupo 2 (áreas não críticas, LSI>3mm). A estabilidade dos mini-implantes foi avaliada mensalmente pela quantificação do grau de mobilidade e a partir dessa variável foi calculada a proporção de sucesso. Avaliou-se também: a quantidade de placa, altura de inserção, grau de sensibilidade e período de observação. RESULTADOS: os resultados obtidos demonstraram que não houve diferença estatisticamente significativa para o grau de mobilidade e proporção de sucesso entre os mini-implantes inseridos em septos de largura mesiodistal crítica e não crítica. A proporção de sucesso total encontrada foi de 90% e nenhuma variável demonstrou estar relacionada ao insucesso dos mini-implantes. No entanto, observou-se maior sensibilidade nos pacientes cujos mini-implantes apresentavam mobilidade, e que a falha desses dispositivos de ancoragem ocorria logo após sua inserção. CONCLUSÃO: a largura do septo inter-radicular no local de inserção não interferiu na estabilidade dos mini-implantes autoperfurantes avaliados neste estudo.

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OBJECTIVES: The aim of this study was to evaluate the effects of non-surgical treatment of periodontal disease during the second trimester of gestation on adverse pregnancy outcomes. MATERIAL AND METHODS: Pregnant patients during the 1st and 2nd trimesters at antenatal care in a Public Health Center were divided into 2 groups: NIG - "no intervention" (n=17) or IG- "intervention" (n=16). IG patients were submitted to a non-surgical periodontal treatment performed by a single periodontist consisting of scaling and root planning (SRP), professional prophylaxis (PROPH) and oral hygiene instruction (OHI). NIG received PROPH and OHI during pregnancy and were referred for treatment after delivery. Periodontal evaluation was performed by a single trained examiner, blinded to periodontal treatment, according to probing depth (PD), clinical attachment level (CAL), plaque index (PI) and sulcular bleeding index (SBI) at baseline and 35 gestational weeks-28 days post-partum. Primary adverse pregnancy outcomes were preterm birth (<37 weeks), low birth weight (<2.5 kg), late abortion (14-24 weeks) or abortion (<14 weeks). The results obtained were statistically evaluated according to OR, unpaired t test and paired t test at 5% signifcance level. RESULTS: No signifcant differences were observed between groups at baseline examination. Periodontal treatment resulted in stabilization of CAL and PI (p>0.05) at IG and worsening of all periodontal parameters at NIG (p<0.0001), except for PI. Signifcant differences in periodontal conditions of IG and NIG were observed at 2nd examination (p<0.001). The rate of adverse pregnancy outcomes was 47.05% in NIG and 6.25% in IG. Periodontal treatment during pregnancy was associated to a decreased risk of developing adverse pregnancy outcomes [OR=13.50; CI: 1.47-123.45; p=0.02]. CONCLUSIONS: Periodontal treatment during the second trimester of gestation contributes to decrease adverse pregnancy outcomes.

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O tratamento convencionalmente preconizado para cães acometidos pela CMD consiste na prescrição de vasodilatadores, agentes inotrópicos positivos (digitálico), diuréticos, dieta hipossódica e, quando necessário, antiarrítmicos. O carvedilol é um β-bloqueador de 3ª geração, não seletivo, que bloqueia igualmente e competitivamente os receptores (β1, β2 e α1). Produz uma evidente vasodilatação periférica, exerce efeitos anti-oxidantes, removendo radicais livres de oxigênio e prevenindo a peroxidação lipídica nas membranas cardíacas, prevenindo a perda de miócitos e a ocorrência de arritmias e reduzindo a taxa de mortalidade em pacientes humanos. O objetivo do presente estudo foi avaliar clínica, eletrocardiográfica, radiográfica e ecocardiograficamente a evolução de cães com cardiomiopatia dilatada (CMD) tratatos com terapia convencional associada ao carvedilol. Para tal foram avaliados 49 cães com CMD divididos em: grupo NT, tratado com terapia convencional, e grupo T, tratado com terapia convencional associada ao carvedilol. Os animais foram submetidos à avaliação clínica e a exames complementares durante o período de um ano. Os resultados demonstraram que a terapia com carvedilol apresentou boa tolerabilidade na dose de 0,3mg kg-1 12-12horas, aumentou a sobrevida dos cães em 30,9%, não alterou as pressões sistólica e diastólica, reduziu a frequência cardíaca após três semanas de terapia, melhorou significantemente as frações de encurtamento e ejeção após seis meses de tratamento, não promoveu alterações radiográficas e da distância E-septo, diminuiu o índice de letalidade da doença, fato demonstrado pela melhora no escore clínico e na classe funcional dos animais, obtida após três semanas de terapia com carvedilol.

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In vitro culture of the mutualistic fungus of leaf-cutting ants is troublesome due to its low growth rate, which leads to storage problems and contaminants accumulation. This paper aims at comparing the radial growth rate of the mutualistic fungus of Atta sexdens rubropilosa Forel in two different culture media (Pagnocca B and MEA LP). Although total MEA LP radial growth was greater all along the bioassay, no significant difference was detected between growth efficiencies of the two media. Previous evidences of low growth rate for this fungus were confirmed. Since these data cannot point greater efficiency of one culture medium over the other, MEA LP medium is indicated for in vitro studies with this mutualistic fungus due its simpler composition and translucent color, making the analysis easier.

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We study how the crossover exponent, phi, between the directed percolation (DP) and compact directed percolation (CDP) behaves as a function of the diffusion rate in a model that generalizes the contact process. Our conclusions are based in results pointed by perturbative series expansions and numerical simulations, and are consistent with a value phi = 2 for finite diffusion rates and phi = 1 in the limit of infinite diffusion rate.

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The growth parameters and the mortality rates of the Scomber japonicus peruanus (Chub mackerel) were studied based on monthly data of frequency of fork length classes obtained from commercial landings off the Peruvian coast from 1996 to 1998. The asymptotic body length and growth rate values obtained by the ELEFAN I (Electronic Length Frequency Analysis) ranged from 40.20 cm to 42.20 cm and from 0.38 to 0.39, respectively. The oscillation amplitude was 0.60; the Winter point values varied from 0.50 to 0.60 and the performance index from 2.79 to 2.84. The total mortality rate of the Chub mackerel obtained by the linearized catch curve oscillated between 1.68 and 3.35. The rate of fishing mortality varied from 1.16 to 2.78 and the exploitation rate from 0.68 to 0.84. The annual rate of natural mortality estimated by the Pauly's method ranged from 0.52 to 0.53. The results obtained allow us to conclude that the longevity of the Chub mackerel was slightly over seven years.

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Every year, autochthonous cases of Plasmodium vivax malaria occur in low-endemicity areas of Vale do Ribeira in the south-eastern part of the Atlantic Forest, state of São Paulo, where Anopheles cruzii and Anopheles bellator are considered the primary vectors. However, other species in the subgenus Nyssorhynchus of Anopheles (e.g., Anopheles marajoara) are abundant and may participate in the dynamics of malarial transmission in that region. The objectives of the present study were to assess the spatial distribution of An. cruzii, An. bellator and An. marajoara and to associate the presence of these species with malaria cases in the municipalities of the Vale do Ribeira. Potential habitat suitability modelling was applied to determine both the spatial distribution of An. cruzii, An. bellator and An. marajoara and to establish the density of each species. Poisson regression was utilized to associate malaria cases with estimated vector densities. As a result, An. cruzii was correlated with the forested slopes of the Serra do Mar, An. bellator with the coastal plain and An. marajoara with the deforested areas. Moreover, both An. marajoara and An. cruzii were positively associated with malaria cases. Considering that An. marajoara was demonstrated to be a primary vector of human Plasmodium in the rural areas of the state of Amapá, more attention should be given to the species in the deforested areas of the Atlantic Forest, where it might be a secondary vector.

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A infecção chagásica foi averiguada entre moradores de duas microrregiões geográficas homogêneas do Estado de São Paulo, entre os anos de 1976 a 1980. Campos de Itapetininga, na região de Sorocaba e Encosta Ocidental da Mantiqueira Paulista, na região de Campinas, foram áreas de colonização de Triatoma infestans, no passado, tendo permanecido, na primeira, até o início da década de 70, como reduto da espécie no estado. Atualmente as duas áreas são colonizadas por triatomíneos da espécie Panstrongylus megistus. Perfis de títulos sorológicos caracterizaram ambas as microrregiões como áreas de baixa endemicidade; a interrupção da transmissão foi mais precoce na Encosta, com diferença de 17 anos, em média. Em Campos de Itapetininga, a intensa exposição ao vetor é traduzida pela sororreatividade observada nas idades superiores a 20 anos, correspondentes aos nascidos antes de 1956. Dentre os nascidos entre 1972 e 1977, nessa área, permanece uma baixa positividade, podendo, também, associar-se à transmissão congênita. Na Encosta, a média de idade dos sororreagentes corresponde a nascimentos na década de 1930; os níveis de positividade variaram nos municípios que a compõe segundo o desenvolvimento de capital. Após 1984, com a adoção de novos critérios para o uso da sorologia no Programa de Controle, o encontro de sororreagente não tem sido associado estatisticamente a moradores notificantes de domicílios com presença de triatomíneos.

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Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E), peak A wave (peak A), E/A ratio (E/A), E wave deceleration time (EDT) and isovolumic relaxation time (IRVT) were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT), by age (peak A and E/A) and by body weight (TRIV). Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.