A new solution to the optimal power flow problem

A new approach to solving the Optimal Power Flow problem is described, making use of some recent findings, especially in the area of primal-dual methods for complex programming. In this approach, equality constraints are handled by Newton's method inequality constraints for voltage and transformer taps by the logarithmic barrier method and the other inequality constraints by the augmented Lagrangian method. Numerical test results are presented, showing the effective performance of this algorithm. © 2001 IEEE.

Urinary flow in children: correlation with age, body height and body surface area

Peak flow rate data (Qmax) are important for diagnosis of lower urinary tract obstruction. However, the lack of uroflowmetry studies in children, makes their interpretation difficult. With this aim, we studied 167 boys classified in four groups according to their age (G1: n = 48, 6-7 years; G2: n = 43, 8-9 years; G3: n = 37, 10-11 years; G4: n = 39, 12-14 years). We studied in all children, weight, height, body surface area, peak flow rate (Qmax) and the correspondant urinary volume (Vol). Means and standard deviations of Qmax (ml/sec) were: 15 +/- 5 (G1), 15 +/- 5 (G2), 17 +/- 5 (G3) and 22 +/- 7 (G4) respectively. Corresponding urinary volumes (Vol) (mean standard deviation-in ml) were: G1 = 123 +/- 75; G2 = 122 +/- 79; G3 = 158 +/- 96 and G4 = 162 +/- 101. We found a significant correlation (p < 0,01) between Qmax and Vol in groups G2, G3 and G4; and between Qmax and height in groups G1 and G4. The authors demonstrated a positive correlation between maximum flow and voided volume, and an increase of Qmax with age.

Space dependency of chemical attributes in an area with sugarcane plantation in Pereira Barreto, SP

The behavior of the chemical attributes is directly influenced by superficial flow and water movement inside the soil. This work aimed to study the space dependency of chemical attributes in an area with sugarcane plantation in Pereira Barreto, SP. An area of 530.67 hectares was mapped using an equipment of Global Positioning System and obtaining a Digital Elevation Model. A set of 134 soil samples were collected every seven hectares in the depths of 0-0.25 m and 0.80-1.00 m. The pH, organic matter (OM), Ca, Mg, K, BS, CEC and base saturation (BS) were analyzed. All the chemical attributes presented similar behavior in the superficial and subsuperficial layer of the soil, which provided better visualization and definition of the homogeneous tillage zones.

Enhancement of optical absorption by modulation of the oxygen flow of TiO2 films deposited by reactive sputtering

Oxygen-deficient TiO2 films with enhanced visible and near-infrared optical absorption have been deposited by reactive sputtering using a planar diode radio frequency magnetron configuration. It is observed that the increase in the absorption coefficient is more effective when the O-2 gas supply is periodically interrupted rather than by a decrease of the partial O-2 gas pressure in the deposition plasma. The optical absorption coefficient at 1.5 eV increases from about 1 x 10(2) cm(-1) to more than 4 x 10(3) cm(-1) as a result of the gas flow discontinuity. A red-shift of similar to 0.24 eV in the optical absorption edge is also observed. High resolution transmission electron microscopy with composition analysis shows that the films present a dense columnar morphology, with estimated mean column width of 40nm. Moreover, the interruptions of the O-2 gas flow do not produce detectable variations in the film composition along its growing direction. X-ray diffraction and micro-Raman experiments indicate the presence of the TiO2 anatase, rutile, and brookite phases. The anatase phase is dominant, with a slight increment of the rutile and brookite phases in films deposited under discontinued O-2 gas flow. The increase of optical absorption in the visible and near-infrared regions has been attributed to a high density of defects in the TiO2 films, which is consistent with density functional theory calculations that place oxygen-related vacancy states in the upper third of the optical bandgap. The electronic structure calculation results, along with the adopted deposition method and experimental data, have been used to propose a mechanism to explain the formation of the observed oxygen-related defects in TiO2 thin films. The observed increase in sub-bandgap absorption and the modeling of the corresponding changes in the electronic structure are potentially useful concerning the optimization of efficiency of the photocatalytic activity and the magnetic doping of TiO2 films. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4724334]

Aplicação integrada de métodos geofísicos em uma área de disposição de resíduos sólidos urbanos em Bauru-SP

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

The influence of area/volume ratio on microstructure and non-Ohmic properties of SnO2-based varistor ceramic blocks

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

Vasopressin and angiotensin receptors of the medial septal area of the brain in the control of thirst and salt appetite induced by vasopressin in water-deprived and sodium-depleted rats

In this study we investigated the influence of d(CH2)(5)-Tyr (Me)-AVP (A(1) AVP) and [Adamanteanacatyl(1),D-ET-D-Tyr(2), Va1(4), aminobutyril(6) ,As-8,As-9]-AVP 9 (A(2)AVP), antagonists of V-1 and V-2 arginine(8)-vasopressin (AVP) receptors, respectively, as well as the effects of losartan and CGP42112A, antagonists of angiotensin II (ANGII) AT(1) and AT(2), receptors, respectively, on water and 0.3 M sodium intake induced by water deprivation or sodium depletion (furosemide treatment) and enhanced by AVP injected into the medial septal area (N4SA). A stainless steel carmulawas implanted into the medial septal area (NISA) of male Holtzman rats AVP injection enhanced water and sodium intake in a dose-dependent manner. Pretreatment with V-1 antagonist injected into the MSA produced a dose-dependent reduction, whereas prior injection of V-2 antagonist increased, in a dose-dependent manner, the water and sodium responses elicited by the administration of AVP. Both AT(1) and AT(2) antagonists administered into the MSA elicited a concentration-dependent decrease in water and sodium intake induced by AVP, while simultaneous injection of the two antagonists was more effective in decreasing AVP responses. These results also indicate that the increase in water and sodium intake induced by AvT was mediated primarily by MSA AT(1) receptors. (c) 2007 Published by Elsevier B.V.

Effects of V-1 and angiotensin receptor subtypes of the paraventricular nucleus on the water intake induced by vasopressin injected into the lateral septal area

In this study, we investigated the influence of d(CH2)(5)-Tyr (Me)-AVP (AAVP) an antagonist of V-1 receptors of arginine(8)-vasopressin (AVP) and the effects of losartan and CGP42112A (selective ligands of the AT, and AT, angiotensin receptors, respectively) injections into the paraventricular nucleus (PVN) on the thirst effects of AVP stimulation of the lateral septal area (LSA). AVP injection into the LSA increased the water intake in a dose-dependent manner. AAVP injected into the PVN produced a dose-dependent reduction of the drinking responses elicited by LSA administration of AVP. Both the AT(1) and AT(2) ligands administered into the PVN elicited a concentration-dependent inhibition in the water intake induced by AVP injected into the LSA, but losartan was more effective than CGP42112A the increase in the AVP response. These results indicate that LSA dipsogenic effects induced by AVP are mediated primarily by PVN 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 angiotensin II (ANG II) receptor subtypes. These results also suggests that facilitatory effects of AVP on water intake into the LSA are mediated through the activation of V-receptors and that the inhibitory effect requires V-receptors. Based on the present findings, we suggest that the administration of AVP into the LSA may play a role in the PVN control of water control. (C) 2003 Elsevier B.V. All rights reserved.

Interaction between paraventricular nucleus and medial septal area on the renal effects induced by adrenaline

The aim of the present study was to analyze the role of alpha(1),alpha(2)-adrenoceptors, and the effects of losartan and PD123319 (selective ligands of the AT(1) and AT(2) angiotensin receptors, respectively) injected into the paraventricular nucleus (PVN) on the diuresis, natriuresis, and kaliuresis induced by administration of adrenaline into the medial septal area (MSA). Male Holtzman rats with a stainless steel cannula implanted into the MSA and bilaterally into the PVN were used. The administration of adrenaline into the MSA increased in a dose-dependent manner the urine, sodium, and potassium excretions. The previous administration of prazosin (an alpha(1)-adrenoceptor antagonist) injected into the PVN abolished the above effects of adrenaline, whereas yohimbine (an a-adrenoceptor antagonist) doesn't affect the diuresis, natriuresis, and kaliuresis induced by adrenaline. Pretreatment with losartan into the PVN decreased in a dose-dependent manner the urine, sodium, and potassium excretions induced by MSA administration of adrenaline (50 ng), while PVN PD123319 was without effect. These results indicate that urinary and electrolyte excretion effects induced by adrenaline into the MSA are mediated primarily by PVN AT, receptors. However, the doses of losartan were more effective when combined with the doses of PD123319 than given alone, suggesting that the urinary, natriuretic, and kaliuretic effects of MSA adrenaline may involve activation of multiple angiotensin II receptors subtypes into the PVN. (C) 2004 Elsevier B.V All rights reserved.

Medial septal area ANG II receptor subtypes in the regulation of urine and sodium excretion induced by vasopressin

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

Role of serotonergic 5-HT1A and oxytocinergic receptors of the lateral septal area in sodium intake regulation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vasopressin and angiotensin receptors of the medial septal area in the control of mean arterial pressure induced by vasopressin

Introduction. Brain arginine(8)-vasopressin (AVP), through the V-1a- and V-2-receptors, is essential for the maintenance of mean arterial pressure (MAP). Central AVP interacts with the components of the renin-angiotensin system, which participate in MAP regulation. This study all to determine the effects of V-1a-, V-2- and V-1a/V-2-AVP selective antagonists and AT(1)- and AT(2)-angiotensin II (Ang II) selective antagonists on the MAP induced by AVP injected into the medial septal area (MSA) of the brain.Materials and methods. Male Holtzman rats with stainless steel cannulae implanted into the MSA were used in experiments. Direct MAP was recorded in Conscious rats.Results. AVP administration into the MSA caused a prompt and potent pressor response in a dose-dependent fashion. Pretreatment with the V-1a- and V-2-antagonists reduced, whereas prior injection of the V-1a/V-2-antagonist induced a decrease in the MAP that remained below the baseline. Both AT(1)- and AT(2)-antagonists elicited a decrease, While simultaneous injections of two antagonists were more effective in decreasing the MAP induced AVP.Conclusion. These results indicate there is a synergism bell the V-1a- and V-2-AVP, and AT(1)- AT, and AT(2)-Ang II receptors in the MSA in the regulation of MAP.

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.

Bird attributes, plant characteristics, and seed dispersal of Pera glabrata (Schott, 1858), (Euphorbiaceae) in a disturbed cerrado area

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

Induced polarization, resistivity, and self-potential: a case history of contamination evaluation due to landfill leakage

This article compares the efficiency of induced polarization (IP) and resistivity in characterizing a contamination plume due to landfill leakage in a typical tropical environment. The resistivity survey revealed denser electrical current flow that induced lower resistivity values due to the high ionic content. The increased ionic concentration diminished the distance of the ionic charges close to the membrane, causing a decrease in the IP phenomena. In addition, the self-potential (SP) method was used to characterize the preferential flow direction of the area. The SP method proved to be effective at determining the flow direction; it is also fast and economical. In this study, the resistivity results were better correlated with the presence of contamination (lower resistivity) than the IP (lower chargeability) data.