2,520 research outputs found
An integrative approach assesses the intraspecific variations of Procamallanus (Spirocamallanus) inopinatus, a common parasite in Neotropical freshwater fishes, and the phylogenetic patterns of Camallanidae
Integrative taxonomy was used to evaluate two component populations of Procamallanus (Spirocamallanus) inopinatus in Brazil and the phylogeny Camallanidae. Parasite populations were collected in the characiform Anostomoides passionis from River Xingu (Amazon basin) and Megaleporinus elongatus from River Miranda (Paraguay basin). Morphology was analysed using light and scanning electron microscopy (SEM). Genetic characterization was based on partial sequences of the 18S and 28S rDNA, and COI mtDNA. Phylogenies were based on 18S and COI due to data availability. Generalized Mixed Yule Coalescent (GMYC), Poisson Tree Process (PTP) and BEAST were used for species delimitation and validation. SEM revealed for the first time the presence of minute denticles and pore-like structures surrounding the oral opening, phasmids in females and confirmed other important morphological aspects. Statistical comparison between the two-component populations indicated morphometric variations, especially among males. The different component population of P. (S.) inopinatus showed variable morphometry, but uniform morphology and were validated as conspecific by the GMYC, PTP and BEAST. Some camallanid sequences in GenBank have incorrect taxonomic labelling. Host, environment and geographic aspects seem to be related to some lineages within Camallanidae; however, their real phylogenetic meanings are still unclear.Fil: Ailan Choke, Lorena Gisela. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto para el Estudio de la Biodiversidad de Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Tavares, Luiz E. R.. Universidade Federal do Mato Grosso do Sul; BrasilFil: Luque, José L.. Universidade Federal do Rio de Janeiro; BrasilFil: Pereira, Felipe B.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasi
Influence of thermal and mechanical fatigue on the shear bond strength of different all-ceramic systems
To evaluate the influence of thermal and mechanical fatigue on the shear bond strength of different all-ceramic cores and veneering porcelain interfaces. All-ceramic systems tested were lithium disilicate and zirconia veneered by layering technique. Sixty specimens (n=20) were subjected to shear bond strength. Ten of them were thermal and mechanical cycled. Fracture analysis was performed with stereomicroscopy and scanning electron microscopy. Energy dispersive X-ray spectroscopy analysis was performed across core/veneer interfaces. Thermal and mechanical cycling did not influence on bond strength. However, there was significant difference among systems (<0.01). CoCr group presented the highest values, followed by lithium disilicate, and zirconia. Failure modes were predominantly adhesive for CoCr, cohesive in core for lithium disilicate, and cohesive in veneer for zirconia. Energy dispersive X-ray showed interaction zone for CoCr and lithium disilicate groups and was inconclusive for zirconia. Fatigue had no influence on bond strength of groups tested. The results suggest that there is a chemical bond between core and veneer materials for CoCr and lithium disilicate groups
Row spacing and seed rating in two wheat cultivars
No período de 1977 a 1979, avaliou-se, em Passo Fundo, RS, EMBRAPA/CNPT, o efeito do espaçamento entrelinhas (10 cm, 20 cm e 30 cm) e da densidade de semeadura (300, 400 e 500 sementes aptas por m2) sobre o comportamento agronômico de duas cultivares de trigo (IAS 54 e CNT 10). O ano e a interação anos x cultivares foram os fatores que mais interferiram no comportamento do trigo. O menor espaço entrelinhas (10 cm) foi o que proporcionou um rendimento de grãos estatisticamente superior aos demais (20 cm e 30 cm). Os acréscimos nas densidades de semeadura diminuíram o número de espigas por planta, aumentando no entanto a população de plantas e o número de espigas por m2. From 1977 to 1979 in Passo Fundo, Rio Grande do Sul State, Brazil, EMBRAPA/CNPT, the effects of row spacing (10 cm, 20 cm and 30 cm) and seeding rate (300, 400 and 500 viable seeds per m2) on agronomic characteristics of two wheat cultivars were assessed. The effect of year and the interaction of year x cultivar were the main factors that influenced wheat yield. The highest yield was obtained under the narrowest row spacing (10 cm), and was significantly greater than other treatments (20 cm and 30 cm). As seeding rates increased, the number of spikes per plant decreased, but plant population and number of spikes per m2 increased.
Cálculo do fluxo de harmônicos em sistemas de potência trifásicos utilizando o método de injeção de correntes com solução iterativa
This work presents a methodology, based on the current injection equations (MICT), for the calculus of the harmonic power flow in three-phase, balanced and unbalanced, electric power systems (MICTH). The developed methodology uses the Newton-Raphson method to obtain the solution of a set of non-linear equations, where the matrix system is built in a blocked form for each harmonic frequency. This mathematical approach permits to represent the interaction between harmonic components of different frequencies. It was also developed models for the main linear and non-linear devices connected to the electric power systems. The MICTH (Three-Phase Harmonic Current Injection Method) and the devices models were implemented in C++ using object-oriented and sparse-matrix programming techniques. The simulation results of the MICTH, obtained in the frequency domain, were validated with simulation results of the ATP/EMTP (Alternative Transients Program of Electromagnetic Transients Program), obtained in the time domain.Este trabalho apresenta uma metodologia, baseada nas equações de injeção de correntes (MICT), para o cálculo do fluxo de potência harmônico trifásico em sistemas elétricos equilibrados e desequilibrados (MICTH). A metodologia desenvolvida emprega o método iterativo de Newton-Raphson para obter a solução do sistema de equações não-lineares, onde o sistema matricial é formado por blocos relativos às freqüências harmônicas investigadas. Dessa maneira é possível representar as interações entre as componentes harmônicas de diferentes freqüências. Em paralelo foram desenvolvidos modelos dos principais dispositivos lineares e não-lineares conectados aos sistemas elétricos de potência. O MICTH (Método de Injeção de Correntes Trifásicas Harmônicas) e os modelos de componentes foram implementados em C++, com programação orientada a objetos, e utilizando técnicas de programação esparsa. Os resultados das simulações, no domínio da freqüência, obtidos com o programa MICTH foram validados a partir de comparações com resultados de simulações, no domínio do tempo, obtidos com o programa ATP/EMTP (Alternative Transients Program of Electromagnetic Transients Program)
Characterization of titanium welded joints by the orbital gas tungsten arc welding process for aerospace application
In this work, three welding programs for orbital gas tungsten arc welding (GTAW), previously developed, were used, using pulsed current and increasing speed (#A), constant current (#B) and pulsed current and decreasing current (#C). One of these should be used for the propulsion system of the Satellite CBERS (China – Brazil Earth Resources Satellite). Welded joints using tubes of commercially pure titanium were obtained with these procedures, which were characterized by means of mechanical and metallographic tests. The obtained results showed that the three welding procedures produce welded joints free of defects and with adequate shape. Although small differences on mechanical properties and on microstructure have been observed, the three welding programs attained compatible results with international standards used in the aerospace segment. The welding program #B, due to the reduced heat input used, was considered to obtain slightly advantage over the others
Effects of cardiopulmonary bypass on propofol pharmacokinetics and bispectral index during coronary surgery
PURPOSE: Cardiopulmonary bypass is known to alter propofol pharmacokinetics in patients undergoing cardiac surgery. However, few studies have evaluated the impact of these alterations on postoperative pharmacodynamics. This study was designed to test the hypothesis that changes in propofol pharmacokinetics increase hypnotic effects after cardiopulmonary bypass. METHODS: Twenty patients scheduled for on-pump coronary artery bypass graft (group, n=10) or off-pump coronary artery bypass graft (group, n=10) coronary artery bypass grafts were anesthetized with sufentanil and a propofol target controlled infusion (2.0 µg/mL). Depth of hypnosis was monitored using the bispectral index. Blood samples were collected from the induction of anesthesia up to 12 hours after the end of propofol infusion, at predetermined intervals. Plasma propofol concentrations were measured using high-performance liquid chromatography, followed by a non-compartmental propofol pharmacokinetic analysis. Data were analyzed using ANOVA, considering p<0.05 as significant. RESULTS: After cardiopulmonary bypass, despite similar plasma propofol concentrations in both groups, bispectral index values were lower in the on-pump coronary artery bypass graft group. Time to extubation after the end of propofol infusion was greater in the on-pump coronary artery bypass graft group (334 ± 117 vs. 216 ± 85 min, p = 0.04). Patients undergoing cardiopulmonary bypass had shorter biological (1.82 ± 0.5 vs. 3.67 ± 1.15h, p < 0.01) and terminal elimination (6.27 ± 1.29 vs. 10.5h ± 2.18, p < 0.01) half-life values, as well as higher total plasma clearance (28.36 ± 11.40 vs.18.29 ± 7.67 mL/kg/min, p = 0.03), compared to patients in the off-pump coronary artery bypass graft group. CONCLUSION: Aside from the increased sensitivity of the brain to anesthetics after cardiopulmonary bypass, changes in propofol pharmacokinetics may contribute to its central nervous system effects
Anti-Hypertensive Drugs Have Different Effects on Ventricular Hypertrophy Regression
OBJECTIVES: There is a direct relationship between the regression of left ventricular hypertrophy (LVH) and a decreased risk of mortality. This investigation aimed to describe the effects of anti-hypertensive drugs on cardiac hypertrophy through a meta-analysis of the literature. METHODS: The Medline (via PubMed), Lilacs and Scielo databases were searched using the subject keywords cardiac hypertrophy, antihypertensive and mortality. We aimed to analyze the effect of anti-hypertensive drugs on ventricle hypertrophy. RESULTS: The main drugs we described were enalapril, verapamil, nifedipine, indapamina, losartan, angiotensin-converting enzyme inhibitors and atenolol. These drugs are usually used in follow up programs, however, the studies we investigated used different protocols. Enalapril (angiotensin-converting enzyme inhibitor) and verapamil (Ca++ channel blocker) caused hypertrophy to regress in LVH rats. The effects of enalapril and nifedipine (Ca++ channel blocker) were similar. Indapamina (diuretic) had a stronger effect than enalapril, and losartan (angiotensin II receptor type 1 (AT1) receptor antagonist) produced better results than atenolol (selective β1 receptor antagonist) with respect to LVH regression. CONCLUSION: The anti-hypertensive drugs induced various degrees of hypertrophic regression
Effect of increasing levels of aluminium on roots of rice grown in nutrient solution
Em casa de vegetação foi estudado o efeito de níveis crescentes de alumínio (0 ppm, 0,5 ppm, 1 ppm, 2 ppm, 4 ppm e 8 ppm) na CTC, volume e peso seco das raízes de arroz (Oryza sativa L.) (IAC-25) em solução nutritiva. Os tratamentos foram realizados quinze dias após a emergência. Semanalmente era trocada a solução e medidos o pH (antes da troca) e teores de Al+++ Com três semanas, as plantas foram colhidas e secadas em estufa, pesando-se raiz e parte aérea. O peso da parte aérea aumentou com doses crescentes de Al, como máximo a 8 ppm de Al. O peso de raízes não diferiu significativamente nos três níveis mais elevados de Al. O Al não afetou o número de perfilhos, mas resultou em aumento do volume das raízes. A capacidade de troca de cátions (CTC) das raízes caiu significativamente, com os níveis crescentes de Al. Com 8 ppm a CTC das raízes foi 48,6% da CTC da testemunha. Observaram- se correlações positivas entre o peso seco da parte aérea, o pH final da solução (r = 0,960**) e o volume das raízes (r = 0,910*). Foram observadas correlações negativas entre a CTC das raízes, o peso seco da parte aérea (r = -0,970**) e o volume das raízes (r =0,970**). Atribui-se a redução da CTC das raízes ao bloqueio não reversível de cargas negativas pelo Al, o que teria aumentado as atividades de H2PO-4 e NO-3 ao nível da plasmalema favorecendo o crescimento das plantas.The effect of aluminium levels (0 ppm, 0.5 ppm, 1 ppm, 2 ppm, 4 ppm and 8 ppm) on the growth of rice (Oryza sativa L.) (IAC-25) was studied under greenhouse conditions. Treatments were applied fifteen days after seed germination. Weekly, pH and Al+++ levels were measured, and the nutrient solution was changed. After three weeks plants were harvested, oven dried, and shoots and roots weighted. The dry weight of the shoots increased with increasing Al level in solution, reaching a maximum at the 8 ppm level. The dry weight of roots also increased but differences were not significant among the three highest levels of Al. Al levels did not affect the tiller number but led to an increase in root volume. Root cation exchange capacity (CEC) decreased significantly with increasing Al levels. At 8 ppm, CEC was only 48,6% in relation to control. There were positive correlations between shoot dry weights, solution pH (r = 0.960**) and root volume (r = 0.910*). Correlations were negative between root CTC, shoot dry weight (r = 0.970**) and root volume (r = -0.970**). The decrease of the CEC of roots may be due to the irreversible blocking of root charges by Al. The positive effect of Al on plant growth, was considered to be due to this blocking of charges on the activity of H2PO-4 and NO-3 at the plasmalemma
Atlantic mammal traits: a dataset of morphological traits of mammals in the atlantic forest of south America
Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from −5.83 to −29.75 decimal degrees of latitude and −34.82 to −56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.Fil: Gonçalves, Fernando. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bovendorp, Ricardo S.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Beca, Gabrielle. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bello, Carolina. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Costa Pereira, Raul. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Muylaert, Renata L.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Rodarte, Raisa R.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Villar, Nacho. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Souza, Rafael. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Graipel, Maurício E.. Universidade Federal de Santa Catarina; BrasilFil: Cherem, Jorge J.. Caipora Cooperativa, Florianopolis; BrasilFil: Faria, Deborah. Universidade Estadual de Santa Cruz; BrasilFil: Baumgarten, Julio. Universidade Estadual de Santa Cruz; BrasilFil: Alvarez, Martín R.. Universidade Estadual de Santa Cruz; BrasilFil: Vieira, Emerson M.. Universidade do Brasília; BrasilFil: Cáceres, Nilton. Universidade Federal de Santa María. Santa María; BrasilFil: Pardini, Renata. Universidade de Sao Paulo; BrasilFil: Leite, Yuri L. R.. Universidade Federal do Espírito Santo; BrasilFil: Costa, Leonora Pires. Universidade Federal do Espírito Santo; BrasilFil: Mello, Marco Aurelio Ribeiro. Universidade Federal de Minas Gerais; BrasilFil: Fischer, Erich. Universidade Federal do Mato Grosso do Sul; BrasilFil: Passos, Fernando C.. Universidade Federal do Paraná; BrasilFil: Varzinczak, Luiz H.. Universidade Federal do Paraná; BrasilFil: Prevedello, Jayme A.. Universidade do Estado de Rio do Janeiro; BrasilFil: Cruz-Neto, Ariovaldo P.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Carvalho, Fernando. Universidade do Extremo Sul Catarinense; BrasilFil: Reis Percequillo, Alexandre. Universidade de Sao Paulo; BrasilFil: Paviolo, Agustin Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; ArgentinaFil: Duarte, José M. B.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil. Fundación Oswaldo Cruz; BrasilFil: Bernard, Enrico. Universidade Federal de Pernambuco; BrasilFil: Agostini, Ilaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; ArgentinaFil: Lamattina, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Ministerio de Salud de la Nación; ArgentinaFil: Vanderhoeven, Ezequiel Andres. Ministerio de Salud de la Nación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin
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