Influence of arginine vasopressin receptors and angiotensin receptor subtypes on the water intake and arterial blood pressure induced by vasopressin injected into the lateral septal area of the rat

In this study we investigated the influence of d(CH2)(5)-Tyr(Me)-[Arg(8)]vasopressin (AAVP) and [adamanteanacetyl(1),0-ET-DTyr(2), Val(4), aminobutyryl(6), Arg(8,9)]-[Arg(8)]vasopressin (ATAVP), which are antagonists of vasopressin V-1 and V-2 receptors, and the effects of losartan, a selective angiotensin AT(1) receptor antagonist, and CGP42112A, a selective AT(2) receptor antagonist, injected into the lateral septal area (LSA) on thirst and hypertension induced by [Arg(8)]vasopressin (AVP). AAVP and ATAVP injected into the LSA reduced the drinking responses elicited by injecting AVP into the LSA. Both the AT(1) and AT(2) ligands administered into the LSA elicited a concentration-dependent decrease in the water intake induced by AVP injected into the LSA, but losartan was more effective than CGP42112A. The increase in MAP, due to injection of AVP into the LSA, was reduced by prior injection of AAVP from 18 +/- 1 to 6 +/- 1 mm Hg. Losartan injected into the LSA prior to AVP reduced the increase in MAP to 7 +/- 0.8 mm Hg. ATAVP and CGP42112A produced no changes in the pressor effect of AVP. These results suggest that the dipsogenic effects induced by injecting AVP into the LSA were mediated primarily by AT(1) receptors. However, doses of losartan were more effective when combined with CGP42112A than when given alone, suggesting that the thirst induced by AVP injections into LSA may involve activation of multiple AVP and angiotensin II receptor subtypes. The pressor response of AVP was reduced by losartan and by AAVP. CGP42112A and ATAVP did not change the AVP pressor response. These results suggest that facilitator effects of AVP on water intake are mediated through the activation of V-1 receptors and that the inhibitory effect requires V-2 receptors. The involvement of AT(1) and AT(2) receptors can be postulated. Based on the present findings, we suggest that the AVP in the LSA may play a role in the control of water and arterial blood pressure balance. (C) 2004 Elsevier B.V. All rights reserved.

Interspecific fish hybrids in Brazil: management of genetic resources for sustainable use

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Photosynthetic limitations caused by different rates of water-deficit induction in Glycine max and Vigna unguiculata

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Short and long period optimization of drug doses in the treatment of AIDS

Técnicas de otimização numérica são úteis na solução de problemas de determinação da melhor entrada para sistemas descritos por modelos matemáticos e cujos objetivos podem ser expressos de uma maneira quantitativa. Este trabalho aborda o problema de otimizar as dosagens dos medicamentos no tratamento da AIDS em termos de um balanço entre a resposta terapêutica e os efeitos colaterais. Um modelo matemático para descrever a dinâmica do vírus HIV e células CD4 é utilizado para calcular a dosagem ótima do medicamento no tratamento a curto prazo de pacientes com AIDS por um método de otimização direta utilizando uma função custo do tipo Bolza. Os parâmetros do modelo foram ajustados com dados reais obtidos da literatura. Com o objetivo de simplificar os procedimentos numéricos, a lei de controle foi expressa em termos de uma expansão em séries que, após truncamento, permite obter controles sub-ótimos. Quando os pacientes atingem um estado clínico satisfatório, a técnica do Regulador Linear Quadrático (RLQ) é utilizada para determinar a dosagem permanente de longo período para os medicamentos. As dosagens calculadas utilizando a técnica RLQ , tendem a ser menores do que a equivalente terapia de dose constante em termos do expressivo aumento na contagem das células T+ CD4 e da redução da densidade de vírus livre durante um intervalo fixo de tempo.

Residual monomer of reline acrylic resins - Effect of water-bath and microwave post-polymerization treatments

Objectives. This study compared the residual monomer (RM) in four hard chair-side reline resins (Duraliner II-D, Kooliner-K, Tokuso Rebase Fast-TRF and Ufi Gel hard-UGH) and one heat-polymerized denture base resin (Lucitone 550-L), which was processed using two polymerization cycles (short-LS and long-LL). It was also investigated the effect of two after polymerization treatments on this RM content.Methods. Specimens (n = 18) of each material were produced following the manufacturers' instructions and then divided into three groups. Group I specimens were left untreated (GI-control). Specimens of group II (GII) were given post-polymerization treatment by microwave irradiation. In group III (GIII), specimens were submitted to immersion in water at 55 degrees C (reline resins-10 min; denture base resin L-60min). The RM was analyzed using high performance liquid chromatography (HPLC) and expressed as a percentage of RM. Data were analyzed by two-way ANOVA followed by Tukey's test (alpha = 0.05).Results. Comparing control specimens, statistical differences were found among all materials (p < 0.05), and the results can be arranged as K (1.52%) > D (0.85%) > UGH (0.45%) > LL (0.24%) > TRF (0.14%) > LS (0.08%). Immersion in hot water (GIII) promoted a significant (p < 0.05) reduction in the RM for all materials evaluated compared to control (GI), with the exception of LL specimens. Materials K, UGH and TRF exhibited significantly (p < 0.05) lower values of RM after microwave irradiation (GII) than in the control specimens.Significance. The reduction in RM promoted by water-bath and microwave post-polymerization treatments could improve the mechanical properties and biocompatibility of the relining and denture base materials. (c) 2006 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Effect of heated solutions on decay control and residues of imazalil in lemons

Freshly harvested lemons [(Citrus limon (L.) Burm)] were dipped 3 min in water with and without imazalil (IMZ) at 50, 100, and 200 ppm at 50 degrees C and at 1000 ppm IMZ at 20 degrees C. Following treatments fruit were kept at 9 degrees C and 90%-95% relative humidity (RH) for 13 weeks and an additional week at 21 degrees C and ca. 75% RH, to simulate a marketing period (SMP). No decay control was observed with fruit dipped in water at 50 degrees C. In contrast, IMZ treatments provided 90%-96% control of Penicillium rots during cold storage and SMP. Fungi other than Penicillium spp. were also found in all samples as differences among treatments were negligible. IMZ treatment caused some external damage to the fruit (peel browning), and the percentage of damaged fruit was related to the amount of active ingredient (AI) present in it. Dipping in 200 or 1000 ppm IMZ promoted off-flavor development after 10 weeks of storage, and fruit were judged to be unacceptable for consumption after 13 weeks of cold storage. After 1000 ppm IMZ dipping at 20 degrees C, residue concentration in fruit was 8.20 ppm; this value doubled that found in a previous investigation on lemons treated with comparable IMZ levels. Residue concentrations in fruit after treatment at 50 degrees C was strictly related to the amount of fungicide employed. After 13 weeks Al residues in fruit decreased to average ca. 35% of the initial values. During the 1 week SMP, residue levels decreased by a further ca. 25%. It was concluded that it is possible to achieve significant control of decay in lemons during longterm storage by dipping fruit in 50 ppm IMZ mixtures at 50 degrees C. Such treatment should be advised to remarkably reduce potential pollution in the environment due to packinghouse wastewater disposal.

Optimized allocation of sectionalizing switches and control and protection devices for reliability indices improvement in distribution systems

Reliability of power supply is related, among other factors, to the control and protection devices allocation in feeders of distribution systems. In this way, optimized allocation of sectionalizing switches and protection devices in strategic points of distribution circuits, improves the quality of power supply and the system reliability indices. In this work, it is presented a mixed integer non-linear programming (MINLP) model, with real and binary variables, for the sectionalizing switches and protection devices allocation problem, in strategic sectors, aimed at improving reliability indices, increasing the utilities billing and fulfilling exigencies of regulatory agencies for the power supply. Optimized allocation of protection devices and switches for restoration, allows that those faulted sectors of the system can be isolated and repaired, re-managing loads of the analyzed feeder into the set of neighbor feeders. Proposed solution technique is a Genetic Algorithm (GA) developed exploiting the physical characteristics of the problem. Results obtained through simulations for a real-life circuit, are presented. © 2004 IEEE.

Influence of arginine vasopressin receptor and nitric oxide on the water, sodium intake and arterial blood pressure induce by angiotensin injected into third ventricle of the brain

As several structures of the central nervous system are involved in the control of hydromineral and cardiovascular balance we investigated whether the natriorhexigenic and pressor response induced by the injection of ANG II into the 3rd V could be mediated by vasopressinergic and nitrergic system. Male Holtzman rats weighing 200-250 g with cannulae implanted into the 3rd V were used. The drugs were injected in 0.5 μL over 30-60 sec. Controls were injected with a similar volume of 0.15 M NaCl. ANGII increased the water intake vs control. AVPA injected into 3rd V prior to ANGII decreased the dipsogenic effect of ANGII. L-arginine also decreased the water intake induced by ANGII. AVPA plus L-arginine inhibit the water intake induced by ANGII. 7NIT injected prior to ANGII potentiated the dipsogenic effect of ANGII. Pre-treatment with ANGII increased the sodium ingestion vs control. AVPA decreased the ANGII effect in sodium intake. L-arginine also decreased the natriorhexigenic effect of ANGII. The combination of L-arginine and AVPA inhibit the sodium intake induced by ANGII. 7NIT injected prior to ANGII potentiated the sodium intake induced by ANGII. ANGII induced an increase in Mean Arterial Pressure (MAP) vs control. AVPA and L-arginine induced a decreased in the pressor effect of ANGII. The combination of L-arginine and AVPA inhibit the pressor effect of ANGII. 7NIT injected prior to ANGII into 3rd V potentiated the pressor effect of ANGII. These data suggest that arginine vasopressin V 1 receptors and Nitric Oxide (NO) within the circumventricular structures may be involved in sodium intake and pressor response induced by the activation of ANGII receptors within the circumventricular neurons. These studies revealed the involvement of sodium appetite by utilizing the angiotensinergic, vasopressinergic and nitrergic system in the central regulation of blood pressure. © 2006 Asian Network for Scientific Information.

The effect of water immersion on the shear bond strength between chairside reline and denture base acrylic resins: Basic science research

Purpose: The effect of water immersion on the shear bond strength (SBS) between 1 heat-polymerizing acrylic resin (Lucitone 550-L) and 4 autopolymerizing reline resins (Kooliner-K, New Truliner-N, Tokuso Rebase Fast-T, Ufi Gel Hard-U) was investigated. Specimens relined with resin L were also evaluated. Materials and Methods: One hundred sixty cylinders (20 × 20 mm) of L denture base resin were processed, and the reline resins were packed on the prepared bonding surfaces using a split-mold (3.5 × 5.0 mm). Shear tests (0.5 mm/min) were performed on the specimens (n = 8) after polymerization (control), and after immersion in water at 37°C for 7, 90, and 180 days. All fractured surfaces were examined by scanning electron microscopy (SEM) to calculate the percentage of cohesive fracture (PCF). Shear data were analyzed with 2-way ANOVA and Tukey's test; Kruskall-Wallis test was used to analyze PCF data (α = 0.05). Results: After 90 days water immersion, an increase in the mean SBS was observed for U (11.13 to 16.53 MPa; p < 0.001) and T (9.08 to 13.24 MPa, p = 0.035), whereas resin L showed a decrease (21.74 MPa to 14.96 MPa; p < 0.001). The SBS of resins K (8.44 MPa) and N (7.98 MPa) remained unaffected. The mean PCF was lower than 32.6% for K, N, and T, and higher than 65.6% for U and L. Conclusions: Long-term water immersion did not adversely affect the bond of materials K, N, T, and U and decreased the values of resin L. Materials L and U failed cohesively, and K, N, and T failed adhesively. © 2007 by The American College of Prosthodontists.

Lower-semicontinuity and optimization of convex functionals

The result that we treat in this article allows to the utilization of classic tools of convex analysis in the study of optimality conditions in the optimal control convex process for a Volterra-Stietjes linear integral equation in the Banach space G([a, b],X) of the regulated functions in [a, b], that is, the functions f : [a, 6] → X that have only descontinuity of first kind, in Dushnik (or interior) sense, and with an equality linear restriction. In this work we introduce a convex functional Lβf(x) of Nemytskii type, and we present conditions for its lower-semicontinuity. As consequence, Weierstrass Theorem garantees (under compacity conditions) the existence of solution to the problem min{Lβf(x)}. © 2009 Academic Publications.

Optimization of a synbiotic formulation of soy yoghurt containing yacon extract by response surface methodology

A synbiotic yoghurt based on a combination of soymilk and yacon water extract (from yacon root tubers) was developed as a novel food product fermented with a probiotic culture of Enterococcus faecium CRL 183 and Lactobacillus helveticus ssp jugurti 4l6. Response surface methodology (RSM) was used to optimize the independent variables soymilk protein concentration and percentage of yacon extract in the formulation through a Central Composite Rotatable Design (CCRD), consisting of a 22 factorial design with two levels (-1, +1), two central points (0) and four axial points (± a, 0) (0, ± α). The responses were assessed by consumer acceptance tests. The optimization indicated that a formulation with a soymilk protein concentration of 1.74g/L and 25.86% of yacon extract gave the best average values, 5.91 for the taste and 6.00 for the overall impression responses. The formulation with 40% of yacon extract and the same concentration of soymilk protein achieved similar acceptance values: taste (5.94) and overall impression (5.87), however, with the extra yacon, it probably had a greater content of prebiotic fructooligosaccharides. Consequently, both formulations may give useful functional foods, with sensory properties comparable with those of soy yoghurt (control formulation). Copyright © 2010 by New Century Health Publishers.

Optimization of satellite constellations in the moon

Nowadays, we return to live a period of lunar exploration. China, Japan and India heavily invest in missions to the moon, and then try to implement manned bases on this satellite. These bases must be installed in polar regions due to the apparent existence of water. Therefore, the study of the feasibility of satellite constellations for navigation, control and communication recovers importance. The Moon's gravitational potential and resonant movements due to the proximity to Earth as the Kozai-Lidov resonance, must be considered in addition to other perturbations of lesser magnitude. The usual satellite constellations provide, as a basic feature, continuous and global coverage of the Earth. With this goal, they are designed for the smallest number of objects possible to perform a specific task and this amount is directly related to the altitude of the orbits and visual abilities of the members of the constellation. However the problem is different when the area to be covered is reduced to a given zone. The required number of space objects can be reduced. Furthermore, depending on the mission requirements it may be not necessary to provide continuous coverage. Taking into account the possibility of setting up a constellation that covers a specific region of the Moon on a non-continuous base, in this study we seek a criterion of optimization related to the time between visits. The propagation of the orbits of objects in the constellation in conjunction with the coverage constraints, provide information on the periods of time in which points of the surface are covered by a satellite, and time intervals in which they are not. So we minimize the time between visits considering several sets of possible constellations and using genetic algorithms.

Diversity management: Challenges, benefits, and the role of human resource management in Brazilian organizations

Purpose The objective of this study was to analyze the major challenges and benefits of diversity management in Brazilian companies by assessing the role of human resources. Design/methodology/approach A total of 15 case studies were carried out on companies that operate in Brazil. Brazil is a country with considerable diversity and multiracial backgrounds. Findings It was found that diversity management in Brazilian companies is still an emerging issue, and the major challenges are related to discriminatory actions taken by coworkers. Among the 15 companies studied, only four had adopted a consistent set of diversity management and human resources practices. These four companies were the only companies to affirm that diversity management requires the strong support of top management and continuous organization to sustain efforts toward incorporating diversity. Originality/value Research studies on diversity management in Brazil are scarce. The findings of this study, however, can be useful to academic professionals and company directors in countries that exhibit similar characteristics to those of Brazil, or to those who are interested in learning more about Brazil. © 2011 Emerald Group Publishing Limited. All rights reserved.

Effects of spray nozzles and spray volume on spodoptera frugiperda management and narrow row corn performance

The high demand of pesticides in the production systems makes the application technology one of the main alternatives to optimize the products efficiency. In this context, the study aimed to evaluate the effects of spray nozzles and spray volumes on spraying deposits, armyworm control and crop corn performance in narrow row sowing system. The experiment was carried out at experimental area of Sao Paulo State University, Campus of Botucatu/SP, Brazil, during the 2009/2010 agricultural season, in randomized blocks with factorial scheme (2x2+1) and four replications. It was tested two flat fan spray nozzles (with and without air induction) combined with two spray volumes (100 and 200 L ha-1) plus a control treatment. There was no influence of spray nozzles (without air induction) in the spray deposits levels on plants. However, the flat fan nozzle with air induction was more effective on fall armyworm, with 100% of control against 47.84% from other at 15 days after spraying. The increase in the spray volume promoted high spray deposits (415.4 and 388.6 μL g-1 dry mass for flat fan nozzle with and without air induction, respectively at V10 growth stage) and consequently, the highest spray volume (200 L-1) was more efficient in the fall armyworm suppression, with 100% of control. All the technologies tested showed lower plant injury from fall armyworm. The insecticide sprayed with different technologies did not affect the parameters of plant height and leaf area index. The corn productivity was directly related with control efficiency of fall armyworm. © 2012 Academic Journals Inc.

Evaluation of soil management and use in an Ultisol in a guava orchard in comparison with a sugarcane field and native forest area

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)