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A geração elétrica brasileira é amplamente dependente das usinas hidroelétricas. Este estudo tem objetivo de verificar o desempenho de diferentes resoluções espaciais do modelo hidrológico semi-distribuído Variable Infiltration Capacity (VIC) acoplado ao modelo meteorológico numérico Eta, este adotado com resolução espacial fixa em 15 km, para a previsão de vazão diária de cinco usinas do Rio Uruguai, no sul do Brasil. O modelo hidrológico foi aplicado para as resoluções 0,04°, 0,08° e 0,16°, em que cada célula de grade contém propriedades uniformes de solo, relevo e vegetação. As usinas hidroelétricas de jusante da área de estudo apresentaram melhor desempenho de previsão de vazão diária pelo modelo VIC para as resoluções mais finas. Conforme o Inventário de Restrições Operativas Hidráulicas dos Aproveitamentos Hidroelétricos (ROH) do Operador Nacional do Sistema (ONS), o efeito da resolução espacial do modelo VIC também foi estudado quanto ao desempenho da previsão diária de riscos de cheias, a partir de matrizes de contingências. Nos picos de cheias, a sensibilidade do modelo a valores acima de cada restrição de segurança (atenção, alerta e emergência) mantém-se invariável igual a 100%, enquanto a precisão variou de 51 a 100%, ambas sem tendência significativa em relação à resolução espacial. Todas as usinas mostraram acurácia mínima de 98,3% e de forma crescente em relação à resolução espacial do modelo. A heterogeneidade de dados físicos foi fator limitante para os ganhos do refinamento da resolução espacial do modelo hidrológico. Palavras-chave: Modelo VIC. Previsão de vazão. Rio Uruguai. Matrizes de contingência.

Energy trading offers great gain opportunities but also exposure to risk due to price volatility. A proper price model is a key element of risk analysis by electricity market traders and represents a strong tool for providing a better understanding of market dynamics. Despite the existing methodologies, the agenda for new research development is still open, mainly considering specific regulatory conditions and the dynamics of energy markets under development. This work provides a technique to simulate stochastic forward price curves for the Brazilian energy market by using stochastic procedures widely used in the financial and stock markets. The results of this work conveniently represent the uncertainty in Brazilian energy market prices and can be applied in risk management and decision making.

The world is undergoing a substantial energy transition with an increasing share of intermittent sources of energy on the grid such as wind and solar. These variable renewable energy sources require an energy storage solution to allow a smooth integration of these sources. Batteries can provide short-term storage solutions. However, there is still a need for technologies that can provide weekly energy storage at locations without potential for pumped hydro storage. This paper presents innovative solutions for energy storage based on “buoyancy energy storage” in the deep ocean. The ocean has large depths where potential energy can be stored in gravitational based energy storage systems. The deeper the system, the greater the amount of stored energy. The cost of Buoyancy Energy Storage Technology (BEST) is estimated to vary from 50 to 100 USD/kWh of stored electric energy and 4,000 to 8,000 USD/kW of installed capacity. BES could be a feasible option to complement batteries, providing weekly storage cycles. As well as from storing energy, the system can also be used to compress hydrogen efficiently.

Land use and water management have considerable impacts on regional climates. This paper proposes that in humid regions with low wind patterns the construction of hydropower storage reservoirs contributes to the increases in the probability of precipitation in the regional climate. This observation has been tested with a methodology that calculates the cumulative influence of reservoir construction in the basins surrounding with a proposed index named Cumulative Impact of Existing Reservoirs, and compares this index with the historical flow of the rivers. It was found that the construction of reservoirs in Brazil had a considerable impact on its river flows.

The energy sector is undergoing substantial transition with the integration of variable renewable energy sources, such as wind and solar energy. These sources come with hourly, daily, seasonal and yearly variations; raising the need for short and long-term energy storage technologies to guarantee the smooth and secure supply of electricity. This paper critically reviews the existing types of pumped-hydro storage plants, highlighting the advantages and disadvantages of each configuration. We propose some innovative arrangements for pumped-hydro storage, which increases the possibility to find suitable locations for building large-scale reservoirs for long-term energy and water storage. Some of the proposed arrangements are compared in a case study for the upper Zambezi water basin, which has considerable water storage limitations due to its flat topography and arid climate. Results demonstrate that the proposed combined short and long-term cycles pumped-storage arrangement could be a viable solution for energy storage and reduce the cost for water storage to near zero.

Este artigo busca analisar as novas politicas de formacao de professores em detrimento das mudancas ocorridas no mundo do trabalho e com base nas politicas educacionais que elas determinam desde a aprovacao da LDBEN. Dando enfase as oportunidades de insercao, de ascensao, como tambem as ofertas de formacao continuada, basilados na verificacao do desempenho de todos que trabalham no magisterio. Ressaltando a hipotese de que um olhar mais rebuscado ha uma relacao intrinseca entre a s formas como o mundo do trabalho esta organizado na sociedade e o trabalho realizado entre os muros da escola, dai dinâmica da sala de aula nao se da de maneira neutra, ela e direcionada, influenciada e modelada pelas relacoes sociais e pelas politicas. Fundamentamos nossa pesquisa em Freire (1989); Bordieu (2001); Freitas (1995); Kuenzer (1998); Dalben (1999); Dupas (1999). Ressaltamos que optamos pela pesquisa bibliografica a partir de uma revisao integrativa da literatura de carater qualitativa, baseados em Souza (2010); Hohendorf(2014); Jacomini(2016); Masson(2012); Borges(2018); Schneider(2012, uma vez que a mesma sera contributiva para professores em formacao e/ou atuantes na educacao basica e no ensino superior. Desta maneira acreditamos que as politicas publicas vem a corroborar com o fortalecimento das formacoes continuadas.

Changes in the climate system and the hydrologic regime strongly affect all water uses and human activity. The main goal of this study is to evaluate the impact of rainfall pattern change on streamflow for 26 Brazilian basins with hydropower plants. More precisely, the goal is to estimate the trends on average streamflow for the 2011–2100 period. The estimated trends result from the analysis of rainfall obtained from a possible climate scenario, among others. The annual average streamflow for this 90-year period is simulated and compared with records from 83 years of observations (1931–2013). Simulations were carried out using two rainfall-to-streamflow hydrological models: Soil Moisture Accounting Procedure (SMAP) and Stochastic Linear Model (SLM). Results from simulations show important impacts, namely, an increase of streamflow in the southern basins and a decrease in the northern basins. Such changes can lead to disastrous consequences, considering the historical exposure to floods and droughts in the southern and northeast regions, respectively. These findings, in addition to the recent severe drought events that have occurred in such regions, provide awareness of a new cycle of reform to the existing water policies and Brazilian institutional framework, which saw the completion of its first 20 years in 2017.

The effects of bad weather conditions on transmission lines associated with high speed wind events have concerned not only industry players, but also the government and consumers of electricity. Recently in Brazil, events of this nature have caused large-scale disruptions in the supply of electricity, resulting in direct economic losses throughout the chain of production and consumption. This paper aimed to propose a methodology for reduction of the occurrence of faults in transmission lines and towers related to high speed wind events and gusts, including a safety analysis and recommendation for corrective maintenance. Results are based on a RD b) the description of wind tunnel tests and computational fluid dynamics (CFD) modeling results aiming at exploring the effectiveness of windbreaks (tree rows alongside the transmission line corridors) as a mean to reduce wind impacts against towers and transmission lines; c) recommendations to reduce the risks of collapse of the transmission infrastructure of large-scale electric power systems which are exposed to extreme weather events. The research development was supported by State Grid Brazil, as a part of their R&D investment in its subsidiary company, Porto Primavera Transmissora de Energia (PPTE) during the years of 2014 and 2015.

This study presents a method based on Archimedean and Gaussian copulas to simulate the occurrence of hydrological droughts. The droughts were characterized by theory of runs for four threshold levels and six univariate probability distributions were evaluated to represent the probabilistic behavior of their severities and durations. The Akaike Information Criterion was used to select the better univariate probabilistic models, while their hypotheses of goodness-of-fit to the historical data were evaluated by Kolmogorov-Smirnov test. Based on the univariate probability distributions of severities and durations, Archimedean and Gaussian copulas were used in the bivariate analysis of the drought events. The proposed method proves to be a useful tool to simulate the occurrence of drought events, preserving the laws of probability of the severities and durations and the dependency between both.

The rise in distributed renewable energy generation creates a growing need to find viable solutions for energy storage to match energy demand and supply at any time. This paper evaluates the possibility of using swimming pools as a long-term cooling energy storage solution, i.e., Swimming Pool Thermal Energy Storage (SPTES). This technology allows a small building to store solar energy for cooling purposes in a yearly cycle, by filling the pool with ice slurry in winter and using that ice to cool the house in the summertime. Additionally, the pool can be used as a heat sink for a heat pump to heat the house during the winter. Results show that the energy storage cost of 0.078 US$ kWhe−1 is substantially smaller when compared with batteries (125 US$ kWhe−1). This makes SPTES a good alternative to support the development of 100% renewable energy systems in locations where the climate has a highly seasonal variation in temperature and the cooling demand is high in summer.

In this chapter is presented a Brazilian capital market good initiatives and improvements: we address some stock market improvements due to corporate governance practices structure development; we discuss correlation between CSR/ESG with operating performance and stock market returns; we describe initiatives undertaken since the middle of 1990s aiming at developing a more robust capital market; we also discuss CSR in a specific sector—the electricity industry, a big business in Brazil.

In hydroelectric systems, water inflow is important to coordinate a cascade and define the energy price. This paper presents a method for managing inflow forecasting studies with a specific module for advanced assessment. The main goal is to provide a structure that facilitates the analysis of water inflow prediction models. A case study has been applied to five mathematical models based on linear regression, artificial neural networks, and hydrologic simulation. These models present daily and monthly inflow forecasts for a set of hydroelectric plants and monitoring stations. The benefits of the proposed method are analyzed in four situations: water inflow prediction, performance evaluation of a specific model, research tool for inflow forecasting, and comparison tool for distinct models. The results show that implementation of the proposed method provides a useful tool for managing inflow forecasting studies and analyzing models. Therefore, it can assist researchers and engineering professionals alike by improving the quality of water inflow predictions.

This paper presents the evaluation of a daily inflow forecasting model using a tool that facilitates the analysis of mathematical models for hydroelectric plants. The model is based on a Fuzzy Inference System. An offline version of the Expectation Maximization algorithm is employed to adjust the model parameters. The tool integrates different inflow forecasting models into a single physical structure. It makes uniform and streamlines the management of data, prediction studies, and presentation of results. A case study is carried out using data from three Brazilian hydroelectric plants of the Parana basin, Tiete River, in southern Brazil. Their activities are coordinated by Operator of the National Electric System (ONS) and inspected by the National Agency for Electricity (ANEEL). The model is evaluated considering a multi-step ahead forecasting task. The graphs allow a comparison between observed and forecasted inflows. For statistical analysis, it is used the mean absolute percentage error, the root mean square error, the mean absolute error, and the mass curve coefficient. The results show an adequate performance of the model, leading to a promising alternative for daily inflow forecasting.

Jogos serios para dispositivos moveis podem auxiliar no processo ensino-aprendizagem de criancas com autismo. Nesse contexto, o presente trabalho se propoe a desenvolver e validar um jogo da forca adaptado para dispositivos moveis que tem como objetivo auxiliar o processo de ensino-aprendizagem de criancas com autismo. O jogo baseia-se em principios da analise do comportamento e aspectos do programa de ensino estruturado TEACCH. O procedimento metodologico envolveu as etapas de levantamento de requisitos, prototipacao, implementacao e validacao com criancas autistas. Tendo como resultado o jogo HangAut Game, alinhado com o formato do ensino estruturado e favorecendo a aprendizagem sem erro.

This paper presents the development of a mathematical model to optimize the management and operation of the Brazilian hydrothermal system. The system consists of a large set of individual hydropowe...

The electricity transmission system lines in the Brazilian re-structured market is the subject on this work. Also are studied transmission lines field procedures considering economy and reliability of ACSR (Aluminum Core Steel Reinforced) cables and compression splices. The work describes compression splices field surveys with suppliers and users concessionaires and also suggest some procedures and inspections routines to improve system reliability.

Este trabalho apresenta um estudo de eficiência energética para o planejamento da operação de estações elevatórias de esgoto (EEE).Verificou-se a necessidade do estudo diante da complexidade da gestão oferta e demanda dos sistemas de esgoto, uma vez que a vazão de efluentes gerada, ao longo do dia, é variável conforme curva apresentada no trabalho e também o custo por Kwh de energia elétrica não é constante durante as 24 horas do dia. Para esta situação formulou-se um modelo de otimização através da técnica de programação linear inteira mista onde procura-se agendar o acionamento e desligamento de bombas hidráulicas com o objetivo de minimizar o custo total com energia elétrica. Para estudo de caso optou-se por modelar o sistema final elevatório de esgoto de uma cidade do interior paulista que representa um problema bastante típico e suficiente para validar a metodologia desenvolvida.

Thalassophryne nattereri (niquim) is a venomous fish responsible for numerous accidents involving fishermen in northern and northeastern Brazil. The aim of the present investigation was to evaluate the action of antivenom on renal effects caused by Thalassophryne nattereri venom. Isolated kidneys of Wistar rats were perfused with a previously dialyzed Krebs-Henseleit solution containing 6 g% bovine serum albumin. The antivenom action was studied through perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF) and glomerular filtration rate (GFR). The niquim venom (1 µg/mL), the antivenom alone (1 µg/mL) or the venom incubated with antivenom were added to the system 30 minutes after the beginning of each perfusion. Previous works have shown venom induced-alterations of renal function parameters. In the isolated rat kidney, T. nattereri venom (1 µg/mL) increased the perfusion pressure and renal vascular resistance at 60, 90 and 120 minutes. UF and GFR also increased at 60, 90 and 120 minutes when compared with the control group; however, no effects were observed on the percent of sodium (%TNa+control = 81.1 ±0.86; %TNa+60 = 78.04 ±1.18; %TNa+90 = 76.16 ±3.34; %TNa+120 = 79.49 ±0.87) and potassium (%TK+control = 72.29 ±1.12; %TK+60 = 75.41 ±0.65; %TK+90 = 71.23 ±2.55; %TK+120 = 76.62 ±1.04) tubular transport. The administration of the antivenom (1 µg/mL) incubated with venom (1 µg/mL) reduced the changes in PP, RVR, UF and GFR provoked by Thalassophryne nattereri venom. The group perfused with venom alone showed a moderate deposit of a proteinaceous material in the tubules and urinary space. The group perfused with the antivenom presented similar results to the control group. In conclusion, the antivenom was able to decrease the effects induced by T. nattereri venom in isolated rat kidney.

Renal changes determined by Lys49 myotoxin I (BmTx I), isolated from Bothrops moojeni are well known. The scope of the present study was to investigate the possible mechanisms involved in the production of these effects by using indomethacin (10 μg/mL), a non-selective inhibitor of cyclooxygenase, and tezosentan (10 μg/mL), an endothelin antagonist. By means of the method of mesenteric vascular bed, it has been observed that B. moojeni myotoxin (5 μg/mL) affects neither basal perfusion pressure nor phenylephrine-preconstricted vessels. This fact suggests that the increase in renal perfusion pressure and in renal vascular resistance did not occur by a direct effect on renal vasculature. Isolated kidneys from Wistar rats, weighing 240–280 g, were perfused with Krebs–Henseleit solution. The infusion of BmTx-I increased perfusion pressure, renal vascular resistance, urinary flow and glomerular filtration rate. Sodium, potassium and chloride tubular transport was reduced after addition of BmTx-I. Indomethacin blocked the effects induced by BmTx-I on perfusion pressure and renal vascular resistance, however, it did not revert the effect on urinary flow and sodium, potassium and chloride tubular transport. The alterations of glomerular filtration rate were inhibited only at 90 min of perfusion. The partial blockade exerted by indomethacin treatment showed that prostaglandins could have been important mediators of BmTx-I renal effects, but the participation of other substances cannot be excluded. The blockage of all renal alterations observed after tezosentan treatment support the hypothesis that endothelin is the major substance involved in the renal pathophysiologic alterations promoted by the Lys49 PLA 2 myotoxin I, isolated from B. moojeni . In conclusion, the rather intense renal effects promoted by B. moojeni myotoxin-I were probably caused by the release of renal endothelin, interfering with the renal parameters studied.

Ophidian accidents caused by the subspecies Crotalus durissus are responsible for high morbity and mortality rates. Acute renal failure is a common complication observed in these accidents. The aim of the present study was to investigate the renal effects promoted by the venom of C. d. collilineatus and its fractions, crotoxin and phospholipase A2. C. d. collilineatus (Cdc; 30 microg mL(-1)), crotoxin (CTX; 10 microg mL(-1)) and phospholipase A2 (PLA2; 10 microg mL(-1)) were tested in isolated rat kidney. The first 30 min of each experiment were used as an internal control and Cdc or its fractions, CTX and PLA2 were added to the system after this period. All experiments lasted 120 min. The venom of Cdc decreased perfusion pressure (PP; control120 = 110.3 +/- 3.69 mmHg; Cdc120 = 96.7+/-8.1 mmHg), renal vascular resistance (RVR; control120 = 6.42+/-0.78 mmHg mL g(-1) min(-1); Cdc120 = 4.8+/-0.56 mmHg/mL g(-1) min(-1)), urinary flow (UF; control120 = 0.19+/-0.03 mL g(-1) min(-1); Cdc120 = 0.12 +/- 0.01 mL g(-1) min(-1)), and glomerular filtration rate (GFR; control120 = 0.79 +/- 0.07 mL g(-1) min(-1); Cdc120 = 0.53 +/- 0.09 mL g(-1) min(-1)), but had no effect on the percent of sodium tubular transport (%TNa+), percent of chloride tubular transport (%TK+) and percent of potassium tubular transport (%TCl-). CTX and PLA2 reduced the GFR, while UF, PP and RVR remained stable during the full 120 min of perfusion. Crotoxin administration also diminished the %TK+ (control120 = 69.94 +/- 6.49; CTX120 = 33.28 +/- 4.78) and %TCl- (control120 = 79.53 +/- 2.67; CTX120 = 64.62 +/- 6.93). PLA2 reduced the %TK+, but exerted no effect on the %TNa+ or on that of TCl-. In conclusion, the C. d. collilineatus venom altered the renal functional parameters evaluated. We suggest that crotoxin and phospholipase A2 were involved in this process, since the renal effects observed would be due to the synergistic action of the components of the venom.

Acute renal failure is the most common complication in the lethal cases caused by snakebites in Brazil. Among the Brazilian venom snakes, Bothrops erythromelas is responsible for the majority of accidents in Northeastern Brazil. Didelphis marsupialis serum could inhibit myonecrotic, hemorrhagic, edematogenic hyperalgesic and lethal effects of envenomation determined by ophidian bites. In the present study, we evaluated the action of the anti-bothropic factor isolated from D. marsupialis on the renal effects promoted by B. erythromelas venom without systemic interference. Isolated kidneys from Wistar rats were perfused with Krebs-Henseleit solution containing 6% bovine serum albumin. We analyzed renal perfusion pressure (PP), renal vascular resistance (RVR), glomerular filtration rate (GFR), urinary flow (UF), and the percentages of sodium and potassium tubular transport (%TNa+, %TK+). The B. erythromelas venom (10 microg mL(-1)) decreased the PP (ct = 108.71+/-5.09 mmHg; BE = 65.21+/-5.6 mmHg*) and RVR (ct = 5.76+/-0.65 mmHg mL(-1) g(-1) min(-1); BE = 3.10+/-0.45 mmHg mL(-1) g(-1) min(-1)*). On the other hand, the GFR decreased at 60 min (ct60 = 0.76+/-0.07 mL g(-1) min(-1); BE60 = 0.42+/-0.12 mL g(-1) min(-1)*) and increased at 120 min (ct120 = 0.72+/-0.01 mL g(-1) min(-1); BE120 = 1.24+/-0.26 mL g(-1) min(-1)*). The UF increased significantly when compared with the control group (ct = 0.14+/-0.01 mL g(-1) min(-1); BE = 0.47+/-0.08 mL g(-1) min(-1)*). The venom reduced the %TNa(+) (ct90 = 79.18+/-0.88%; BE90 = 58.35+/-4.86%*) and %TK+ (ct90 = 67.20+/-4.04%; BE90 = 57.32+/-5.26%*) The anti-bothropic factor from D. marsupialis (10 microg mL(-1)) incubated with B. erythromelas venom (10 microg mL(-1)) blocked the effects on PP, RVR, %TNa+, and %TK+, but was not able to reverse the effects in UF and GFR promoted by venom alone. However, the highest concentration of D. marsupialis serum (30 microg mL(-1)) reversed all the renal effects induced by the venom. In conclusion, B. erythromelas venom altered all the renal functional parameters evaluated and the anti-bothropic factor from D. marsupialis was able to inhibit the effects induced by the venom in isolated kidney.

Lectins are glycoproteins that interact reversibly and specifically with carbohydrates. The renal effects of the galactose-binding lectin from the seeds of Vatairea macrocarpa were investigated. Isolated kidneys from Wistar rats (240–280 g) were perfused with Krebs-Henseleit solution containing 6% bovine serum albumin. The V. macrocarpa lectin (10 μg mL−1) increased the perfusion pressure, renal vascular resistance, urinary flow and glomerular filtration rate. However, V. macrocarpa lectin did not change the percentage sodium, potassium or chloride tubular transport. Pretreatment with lectin-galactose complex significantly blocked the increase in perfusion pressure, renal vascular resistance, urinary flow and glomerular filtration rate. The control group showed a small amount of a proteinaceous material in the urinary space, although no alteration in the renal tubules was detected. The administration of galactose alone did not modify the functional parameters of the kidney. Kidneys perfused with V. macrocarpa lectin showed moderate deposits of a proteinaceous material in the tubules and urinary space. Those pre-treated with lectin-galactose complex had only small amount of a proteinaceous material in the urinary space. No abnormalities were seen in renal tubules. The results suggest that lectin from V. macrocarpa seeds has important effects on the carbohydrate-binding sites of the renal system, given the reversal of renal effects with the use of that specific inhibitor.

This work reviews the most significant stages of the past and recent evolution of the electrical energy deregulation that took place in Brazil. The past alternate cycles of the State and private ownership of hydroelectric projects across the country is discussed, as well as the recent large privatization process that is currently also including thermal plants. The issues dealt with in this paper concern the requirement that deregulation certainly be coupled with effective competition and gains in economy efficiency, but these are only some of the many issues that must be addressed. The possible different perspectives from public and private viewpoints are examined for the short and long run.

Acute renal failure is one the most common systemic complications after snakebite, however, its pathogenesis remains obscure. In this study we evaluated the renal effects of Bothrops moojeni venom and its myotoxins (Bmtx-I and BmtxII) in rat isolated perfused kidneys. The myotoxins were purified by ion-exchange chromatography and reverse phase HPLC. The whole venom (10 μg/ml) and myotoxins (5 μg/ml) were added to the perfusion system 30 min after the beginning of each perfusion. The renal effects were compared to a control group perfused with modified Krebs–Henseleit solution alone. B. moojeni venom decreased the perfusion pressure (PP), renal vascular resistance (RVR), and the percent sodium, potassium and chloride tubular transport (%TNa + , %TK + , %TCl − ). In contrast, the venom increased the urinary flow (UF), glomerular filtration rate (GFR), and the sodium, potassium and chloride excretion (ENa + , EK + , ECl − ). The renal effects of myotoxin I was very similar to those of the whole venom, but there was an increase rather than a decrease in the PP and RVR. Myotoxin II had no effect on renal physiology, except for a transient decrease in %TK + . In conclusion, B. moojeni venom caused intense alterations in renal physiology, including a drop in vascular resistance associated with diuresis, natriuresis and kaliuresis. Bmtx-I had an opposite effect when compared to whole venom, showed in the parameters of PP and RVR. Bmtx-II had a mild effect in %TK + . The apparent inability of Bmtx-II to induce the renal effect similarly to Bmtx-I should be explained by the absence in the Bmtx-II of the C-terminal lysine rich region.

The lectin from the seeds of Canavalia brasiliensis (Con Br) was tested for its renal effects using the isolated perfusion rat kidney method. Three different doses were examined (3,10 and 30 microgram / ml), which were compared with a control group. The control group was perfused with only Krebs-Henseleit solution containing 6 percent BSA. Con Br caused diuresis and natriuresis, with a mild alteration on the perfusion pressure. Probably the lectin is inhibiting the Na+ / K+ / 2Cl- transporter present in the thick ascending limb of the Henle´s loop.

A linear programming model has been developed for optimal cash flow management addressing specific cash flow issues related to the construction industry. These include typical financial transactions, possible delays on payments, use of available credit lines, effect of changing interest rates, and budget constraints that often occur in the construction industry. A small size project from the Brazilian construction industry is provided as a case study, aiming at evaluating the potential benefits from using the model. Different changes to the basic structure of the model allow and establish the consistency of the results. Alternative formulations are suggested to deal with uncertainties, longer planning horizons, and multiple subcontractors and suppliers. In addition to the tangible financial earnings derived from the optimization process, the simple structure of the model, as a network flow and corresponding equations, provides much visual insight concerning the relationships between the external inputs an...

A network flow algorithm has been developed for the optimization of real-time operation of a multiple reservoir system. Two purposes have been considered in the operation: flood control and hydropower generation. A special network structure was developed which allows the consideration of river routing. A multiobjective formulation is utilized thus allowing generation of a non-dominated curve. The effect of imperfect forecast on the performance of the real-time operation model is also evaluated. An application is made to a subsystem of the Brazilian hydroelectric system, located in the Paranapanema river basin. In this case study, the model showed good performance under the largest flood of the historical records.

The Brazilian hydrothermal system consists of a completely linked network of 143 medium and large hydropower plants, 888 small hydropower plants, and 1602 thermal and 82 wind power plants, with a total installed capacity of 128,570 MW. The hydropower plants produce, on average, 91% of the total electricity consumed in the country, while the complementary thermal system is dispatched mainly during periods of drought. In our previous studies, we developed a nonlinear programming model, HIDROTERM, to optimize the management and operation of the hydrothermal system, considering individual hydropower plants, thermal generation and exchange, multiple uses of the water, and system expansion. The model is deterministic. In this paper, we develop a new version of HIDROTERM to incorporate the stochasticity of the inflows in the formulation. Additionally, hourly load variation is represented by three levels: peak, base, and low. The proposed approach is based on a two-stage stochastic programming with recourse. In the first stage (first time period) the system passes from its initial state to the final state based on deterministic inflow forecasts. From the second time period on (the second stage), the state of the system branches out according to inflow scenarios. The branching can be scaled up gradually until the end of the planning horizon. New developments are made in the formulation, interface, database and the underlying simulation model. The newly developed integrated decision support system is being tested on the entire Brazilian hydrothermal system. 1 Assistant Professor, University of Sao Paulo; e-mail: rczambon@usp.br; ASCE/EWRI Member 2 Professor, University of Sao Paulo, Brazil; e-mail: mtbarros@usp.br; ASCE Member 3 Professor, University of Campinas; e-mail: franco@fec.unicamp.br 4 Assistant Professor, University of Campinas; e-mail: francato@fec.unicamp.br 5 Consulting Engineer; e-mail: jelopes1@gmail.com 6 Engineer, Companhia Energetica de Sao Paulo; e-mail: luis.nogueira@cesp.com.br 7 Distinguished Professor, UCLA; e-mail: williamy@seas.ucla.edu; ASCE Honorary Member 1563 World Environmental and Water Resources Congress 2013: Showcasing the Future © ASCE 2013

O objetivo deste trabalho foi avaliar os efeitos da inclusão de farinha de folha de leucena em dietas sobre a composição corporal de juvenis de tambaqui. Um total de 240 juvenis foram distribuídos em 12 caixas plásticas (350 L), em um delineamento experimental inteiramente casualizado com quatro tratamentos (0, 8, 16 e 24 % de inclusão de farinha de folha de leucena) e três repetições. Não houve diferença significativa (p>0,05) entre os tratamentos, indicando que é possível incluir até 24 % de farinha de folha de leucena em rações para juvenis de tambaqui, sem que haja alteração da composição corporal.

This paper presents the application of a methodology for daily reservoir inflow forecasting in Brazilian hydroelectric plants. The methodology is based on Fuzzy Inference Systems (FIS) and the technique used for adjusting of the model parameters is an offline version of the Expectation Maximization (EM) algorithm. In order to automate the application of the methodology and facilitate the analysis of the results, a tool that allows managing streamflow forecasting studies and visualizing their information in graphical form was developed. A case study was applied to the data from three Brazilian hydroelectric plants whose operation is under the coordination of the Electric System National Operator. They are located in the Grande basin, a part of the Parana basin with two main rivers: the Grande and the Pardo. The benefits of the model are analyzed using statistics calculations, such as: root mean square error, mean absolute percentage error, mean absolute error and mass curve coefficient. Besides that, graphics that compare the registered and predicted streamflow are presented. The results show an adequate performance of the model, leading to a promising alternative for daily streamflow forecasting.

Given the importance of controlling floods in valleys and their impacts on the operation planning of hydropower plants, this research work aims at developing a contribution for finding a systematic metrics and risk criteria acceptance. It is assumed that each hydropower plant has a maximum flow constraint at downstream valley, thus requiring protection through operational procedures of the spillway and turbines. The decision about which risk level is acceptable for protection against flooding in the corresponding valleys should consider the nature, the complexity for control and the magnitude of the consequences of flooding. In general terms, high impacts will require low acceptable risk levels and, high complexity for flood control operation will require low acceptable risk levels. In order to describe the magnitude of consequences under flooding beyond the threshold level (maximum flow constraint), six severity descriptors were defined based on social impacts, possible fatalities, economic damages, operational damages, environmental damages and reputation losses to the image of the generation company. The severity descriptors are measured by using qualitative scales (low, moderate, high, catastrophic) with detailed instructions about the situations that leads to each position in the several scale levels. Similarly, five complexity operational flood control descriptors are also defined, with the corresponding qualitative scales. The proposed methodology is applied on a system of hydropower plants of the power generation company Companhia Energetica de Sao Paulo (CESP). This case study was developed with the collaboration of the technical staff of CESP, including professionals of different branches of the company. The results exhibits consistency, thus revealing the proposed methodology as an useful tool for supporting decision about risk criteria acceptance.

Sea anemones contain a variety of biologically active substances. Bunodosoma caissarum is a sea anemone from the Cnidaria phylum, found only in Brazilian coastal waters. The aim of the present work was to study the biological effects of PLA(2) isolated from the sea anemone B. caissarum on the isolated perfused kidney, the arteriolar mesenteric bed and on insulin secretion. Specimens of B. caissarum were collected from the Sao Vicente Channel on the southern coast of the State of Sao Paulo, Brazil. Reverse phase HPLC analysis of the crude extract of B. caissarum detected three PLA(2) proteins (named BcPLA(2)1, BcPLA(2)2 and BcPLA(2)3) found to be active in B. caissarum extracts. MALDI-TOF mass spectrometry of BcPLA(2)1 showed one main peak at 14.7 kDa. The N-terminal amino acid sequence of BcPLA(2)1 showed high amino acid sequence identity with PLA(2) group III protein isolated from the Mexican lizard (PA23 HELSU, HELSU, PA22 HELSU) and with the honey bee Apis mellifera (PLA(2) and 1POC_A). In addition, BcPLA(2)1 also showed significant overall homology to bee PLA(2). The enzymatic activity induced by native BcPLA(2)1 (20 microg/well) was reduced by chemical treatment with p-bromophenacyl bromide (p-BPB) and with morin. BcPLA(2)1 strongly induced insulin secretion in presence of high glucose concentration. In isolated kidney, the PLA(2) from B. caissarum increased the perfusion pressure, renal vascular resistance, urinary flow, glomerular filtration rate, and sodium, potassium and chloride levels of excretion. BcPLA(2)1, however, did not increase the perfusion pressure on the mesenteric vascular bed. In conclusion, PLA(2), a group III phospholipase isolated from the sea anemone B. caissarum, exerted effects on renal function and induced insulin secretion in conditions of high glucose concentration.

Brazil’s poorest region, located in the country’s northeast, suffers mainly because of its dry climate and limited water resources. The demand for water and irrigation is very high, and shifts in Brazilian water resources policy can minimize drought social impacts. The most important source of water supply is the Sao Francisco river basin. Many years ago a water transfer system was designed in order to address the planned irrigation demand in the dry area. At that time the main conflict was between irrigation demand and the hydroelectrical impacts on the Sao Francisco hydropower system. The project changed its basic objectives and today the main water uses are irrigation and water supply in many cities located in the dry areas. Today the quantity of water planned to be transferred from the Sao Francisco river to the semi-arid area of the northeast region known as the “Drought Polygon” is small compared to the originally proposed amount, so the impacts on hydropower production are minimized. Despite this the project is still very controversial due mainly to its negative environmental impacts related to water quality in the Sao Francisco river. In order to minimize these impacts it is necessary to develop a highly efficient model to plan the operation of the system. The SISAGUA model developed by Barros et al. (2005) is a very convenient tool to accomplish this goal. This paper presents the application of SISAGUA to the optimal operation of the Sao Francisco river water transfer system and some very interesting results related to environmental impacts.

One of the most critical problems that all megacities (cities with more than 10 million people) face today is the shortage of water supply. Finding a solution to this problem presents a great challenge to hydrologists, urban planners and environmentalists. This paper describes the development of an optimization model for planning and operation of a large-scale water supply distribution system. An important characteristic of the model is that it considers the hedging rules during a dry period when water supply is insufficient to meet the planned demand and water shortage occurs. The water distribution system is formulated as a network flow model in terms of nodes and links and solved by the GAMS language, which has access to several linear and nonlinear algorithms. A user friendly interface is developed to facilitate the manipulation of a large amount of data and to generate graphs and tables for analysis for decision makers. The developed methodology has been implemented for the Sao Paulo Metropolitan Area Water Distribution System that supplies water to 18 million people. Some preliminary results obtained show good performance of the model.

Chloride ions can infiltrate concrete by a variety of ways, including admixtures, contaminated sand, or external penetration. When the concentration of chloride ions reaches a critical level, the corrosion begins. This article reports on a study that evaluated the method of electrochemical extraction of chloride ions for the rehabilitation of concrete structures with reinforcement corrosion. The authors investigated the influence of the concrete cover and the water-cement ratio (w/c) in the efficiency of the method by determining the initial and the final chloride content. Electrochemical impedance spectroscopy and the corrosion potential were used to monitor the reinforcement electrochemical behavior during the chloride extraction. The test results verified that the method successfully extracted chloride ions. On average, 77% of the content of initial chloride ions at a distance of 0.5 cm from the surface (depth where the slices had been extracted) were removed. The study used tap water as the electrolyte, which caused high polarization of the reinforcing bars during the extraction; the authors recommend an alkaline solution for future studies. The porosity of the concrete was not affected by the electrochemical chloride extraction.

Bothrops jararacussu myotoxin I (BthTx-I; Lys 49) and II (BthTX-II; Asp 49) were purified by ion-exchange chromatography and reverse phase HPLC. In this work we used the isolated perfused rat kidney method to evaluate the renal effects of B. jararacussu myotoxins I (Lys49 PLA2) and II (Asp49 PLA2) and their possible blockage by indomethacin. BthTX-I (5 microg/ml) and BthTX-II (5 microg/ml) increased perfusion pressure (PP; ct120=110.28+/-3.70 mmHg; BthTX I=171.28+/-6.30*mmHg; BthTX II=175.50+/-7.20*mmHg), renal vascular resistance (RVR; ct120=5.49+/-0.54 mmHg/ml.g(-1)min(-1); BthTX I=8.62+/-0.37*mmHg/ml g(-1)min(-1); BthTX II=8.9+/-0.36*mmHg/ml g(-1)min(-1)), urinary flow (UF; ct(120)=0.14+/-0.01ml g(-1)min(-1); BthTX I=0.32+/-0.05*ml g(-1)min(-1); BthTX II=0.37+/-0.01*ml g(-1)min(-1)) and glomerular filtration rate (GFR; ct120=0.72+/-0.10 ml g(-1)min(-1); BthTX I=0.85+/-0.13*ml g(-1)min(-1); BthTX II=1.22+/-0.28*ml g(-1)min(-1)). In contrast decreased the percent of sodium tubular transport (%TNa(+); ct(120)=79,76+/-0.56; BthTX I=62.23+/-4.12*; BthTX II=70.96+/-2.93*) and percent of potassium tubular transport (%TK(+);ct120=66.80+/-3.69; BthTX I=55.76+/-5.57*; BthTX II=50.86+/-6.16*). Indomethacin antagonized the vascular, glomerular and tubular effects promoted by BthTX I and it's partially blocked the effects of BthTX II. In this work also evaluated the antibacterial effects of BthTx-I and BthTx-II against Xanthomonas axonopodis. pv. passiflorae (Gram-negative bacteria) and we observed that both PLA2 showed antibacterial activity. Also we observed that proteins Also we observed that proteins chemically modified with 4-bromophenacyl bromide (rho-BPB) decrease significantly the antibacterial effect of both PLA2. In conclusion, BthTx I and BthTX II caused renal alteration and presented activity antimicrobial. The indomethacin was able to antagonize totally the renal effects induced by BthTx I and partially the effects promoted by BthTx II, suggesting involvement of inflammatory mediators in the renal effects caused by myotoxins. In the other hand, other effects could be independently of the enzymatic activity of the BthTX II and the C-terminal domain could be involved in both effects promoted for PLA2.