Avaliação Da Estabilidade De Tensão Do Sistema Brasileiro - Um Caso De Estudo

This paper presents results of a study of the Brazilian system operation in respect to voltage stability criteria. The analyses are applied using real-life data from the operation and planning. The system is divided in 4 regions: North, Northeast, South and Southeast/West Center. System stability margin is evaluated for each one of these areas. The results show that Brazilian system has stability margin much lower than the existing voltage stability criteria, limited by the Southeast/West Center region. A detailed analysis of this critical area is performed. This paper also presents the stability margin behavior during a typical weekday curve and a contingency analysis. The contingency severity is verified by using the modal analysis technique assessing each contingency impact classifying as local, area or systemic.193327336Affonso, C.M., Da Silva, L.C.P., Lima, F.G.M., Soares, S., MW and MVar Management on Supply and Demand Side for Meeting Voltage Stability Margin Criteria (2004) IEEE Transactions on Power Systems, 19 (3), pp. 1538-1545Affonso, C.M., Da Silva, L.C.P., Voltage Stability Improvement by Optimizing Reactive Power Reserves (2004) Proceedings of the Fourth IASTED International Conference - Power and Energy Systems, pp. 394-399. , Rhodes, Greece, ppAmjady, N., A Framework of Reliability Assessment With Consideration Effect of Transient and Voltage Stabilities (2004) IEEE Transactions on Power Systems, 19 (2), pp. 1005-1014Bao, L., Huang, Z., Xu, W., Online Voltage Stability Monitoring Using Var Reserves (2003) IEEE Transactions on Power Systems, 18 (4), pp. 1461-1469CEPEL (2004). Programa de Análise de Redes / ANAREDE - Manual do Usuário Versão 08-8/2004. Rio de Janeiro, RJ, BrasilCorsi, S., Sabelli, C., General Blackout in Italy Sunday September 28, 2003, h. 03:28:00 (2004) Proceedings of IEEE Power Engineering Society General Meeting, 2, pp. 1691-1702Da Silva, L.C.P., Wang, Y., Da Costa, V.F., Xu, W., Assessment of generator impact on system power transfer capability using modal participation factors (2002) Proc. IEE Gener. Transm. Distrib, 149Tarefa, F., Critérios e Metodologias Estabelecidos no âmbito da Força - Tarefa Colapso de Tensão do GTAD/SCEL/GCOI para Estudos de Estabilidade de Tensão nos Sistemas Interligados Norte/Nordeste, Sul/Sudeste e Norte/Sul Brasileiros (1999) Anais do XV SNP-TEE, , Foz do Iguaçu, PR, BrasilDefinition and Classification of Power System Stability (2004) IEEE Transactions on Power Systems, 19 (2), pp. 1387-1401. , IEEE/CIGRE Joint Task Force on Stability Terms and DefinitionsKabouris, J., Vournas, C.D., Efstathiou, S., Manos, G.A., Contaxis, G.C., Voltage Security Considerations in an Open Power Market (2000) Proceedings of IEEE International Conference on Electric Utility Deregulation and Restructuring and Power Technologies, pp. 278-283Kamalasadan, S., Srivastava, A.K., Thukaram, D., Novel Algorithm for Online Voltage Stability Assessment Based on Feed Forward Neural Network (2006) Proc. IEEE Power Engineering Society General Meeting, pp. 1-7Kundur, P. (1994). Power System Stability and Control. Ed. New York: McGraw-HillONS (2002) Procedimentos de Rede Módulo 21: Estudos Especiais. Submódulo 21.5: Estudos de Estabilidade de Tensão. http://www.ons.org.brTaylor, C.W., (1994) Power System Voltage Stability, , New York: McGraw-Hill IncU.S.-Canada Power System Outage Task Force (Apr., 2004). Final Report on the August 14, 2003 Blackout in the United States and Canada: Causes and Recommendations. http://www.iwar.org.uk/cip/resources/blackout-03/WECC Reactive Power Reserve Work Group (1998). Final Report: Voltage Stability Criteria, Undervoltage Load Shedding Strategy, and Reactive Power Reserve Monitoring Methodology. http://www.wecc.bi

In vivo and in vitro heat shock proteins gene expression in cattle.

The main purpose for this study was the quantification of the heat shock proteins HSPA1A and HSP90AA1, in cow lymphocytes, when subjected to heat stress directly - in vivo, or indirectly - in vitro. The aim was to identify differences between HSP expression in vitro and in vivo. The experiment was conducted in the Biometeorology and Ethology Laboratory of FZEA-USP. Were used three female Holstein Frisian, which were subjected to heat stress, by sun exposure. The blood samples were collected after sun exposure, with a temperature of 40 ± 2 º C, during three days. For in vitro tests, blood of the same animals was collected and placed for a period of 4 hours in a water bath at 40 º C, thus simulating the thermal stress. Total RNA of lymphocytes was extracted, treated with DNase I and submitted to cDNA synthesis for gene expression quantification of HSPA1A and HSP90AA1, by real time PCR (qRT-PCR). The data were tested for normality by Kolmogorov-Smirnov test and for homocedasticity by Levene test. Data were analyzed according to a general linear model procedure with 2 fixed factors treatment and genes expression. Significantly different means were submitted to post-hoc comparisons of means (LSD test) and regarded as significantly different when P<0.05. The results showed that there are no significant differences between the in vitro and the in vivo treatments

Combining photodynamic therapy with immunostimulatory nanoparticles elicits effective anti-tumor immune responses in preclinical murine models

Photodynamic therapy (PDT) has shown encouraging but limited clinical efficacy when used as a standalone treatment against solid tumors. Conversely, a limitation for immunotherapeutic efficacy is related to the immunosuppressive state observed in large, advanced tumors. In the present study, we employ a strategy, in which we use a combination of PDT and immunostimulatory nanoparticles (NPs), consisting of poly(lactic-co-glycolic) acid (PLGA)-polyethylene glycol (PEG) particles, loaded with the Toll-like receptor 3 (TLR3) agonist poly(I:C), the TLR7/8 agonist R848, the lymphocyte-attracting chemokine, and macrophage inflammatory protein 3 alpha (MIP3 alpha). The combination provoked strong anti-tumor responses, including an abscopal effects, in three clinically relevant murine models of cancer: MC38 (colorectal), CT26 (colorectal), and TC-1 (human papillomavirus 16-induced). We show that the local and distal anti-tumor effects depended on the presence of CD8(+) T cells. The combination elicited tumor-specific oncoviral- or neoepitope-directed CD8(+) T cells immune responses against the respective tumors, providing evidence that PDT can be used as an in situ vaccination strategy against cancer (neo)epitopes. Finally, we show that the treatment alters the tumor microenvironment in tumor-bearing mice, from cold (immunosuppressed) to hot (pro-inflammatory), based on greater neutrophil infiltration and higher levels of inflammatory myeloid and CD8(+) T cells, compared to untreated mice. Together, our results provide a rationale for combining PDT with immunostimulatory NPs for the treatment of solid tumors.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas

Economic Impact of a Rotavirus Vaccine in Brazil

The study was done to evaluate the cost-effectiveness of a national rotavirus vaccination programme in Brazilian children from the healthcare system perspective. A hypothetical annual birth-cohort was followed for a five-year period. Published and national administrative data were incorporated into a model to quantify the consequences of vaccination versus no vaccination. Main outcome measures included the reduction in disease burden, lives saved, and disability-adjusted life-years (DALYs) averted. A rotavirus vaccinationprogramme in Brazil would prevent an estimated 1,804 deaths associated with gastroenteritis due to rotavirus, 91,127 hospitalizations, and 550,198 outpatient visits. Vaccination is likely to reduce 76% of the overall healthcare burden of rotavirus-associated gastroenteritis in Brazil. At a vaccine price of US$7-8 per dose, the cost-effectiveness ratio would be US$ 643 per DALY averted. Rotavirus vaccination can reduce the burden of gastroenteritis due to rotavirus at a reasonable cost-effectiveness ratio

Nutritional Evaluation Of Children With Chronic Cholestatic Disease

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)To evaluate the nutritional status of children with persistent cholestasis and to compare the anthropometric indices between children with and without liver cirrhosis and children with and without jaundice. Methods Children with persistent cholestasis, i.e. increased direct bilirrubin or changes in the canalicular enzyme gamma-glutamyl transferase (GGT), were included. The anthropometric measures were weight (W), height or length (H), arm circumference (AC), triceps skinfold thickness (TST), arm muscle circumference (AMC), and body mass index (BMI). Results Ninety-one children with cholestasis, with current median age of 12 months, were evaluated. W/age (A) and H/A indices below -2 Z-scores were observed in 33% and 30.8% of patients, respectively. Concerning the W/H index and BMI, only 12% and 16% of patients, respectively, were below -2 Z-scores. Regarding AC, 43.8% of 89 evaluated patients had some depletion. Observing the TST, 64% of patients had depletion, and 71.1% of the 45 evaluated patients had some degree of depletion regarding the ACM index. Conclusion Evaluation using weight in patients with chronic liver diseases may overestimate the nutritional status due to visceromegaly, subclinical edema, or ascites. Indices that correlate weight and height, such as W/H and BMI, may also not show depletion because of the chronic condition in which there are depletion of both weight and height. TST, AC, and ACM are parameters that better estimate nutritional status and should be part of the management of patients with liver diseases and cholestasis. © 2015 Sociedade Brasileira de Pediatria.922197205CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Cholesterol-functionalized carvedilol-loaded PLGA nanoparticles: anti-inflammatory, antioxidant, and antitumor effects

The inflammation has been identified as factor of tumor progression, which has increased the interest and use of molecules with anti-inflammatory and antioxidant activities in the cancer treatment. In this study, the antioxidant, anti-inflammatory, and antitumor potentials of carvedilol was explored in a different approach. The cholesterol (CHO) was investigated as facilitated agent in the action of carvedilol-loaded nanoparticles. Different formulations exhibited spherical and stable nanoparticle with mean diameter size < 250 nm. The cholesterol changed the copolymer-drug interactions and the encapsulation efficiency. The in vitro cancer study was performed using murine colorectal cancer cell line (CT-26) to observe the cell viability and apoptosis on MTS assay and flow cytometry, respectively. The experiments have demonstrated that cholesterol improved the performance of drug-loaded nanoparticles, which was much better than free drug. The in vivo inflammation peritonitis model revealed that carvedilol-loaded nanoparticles increased the level of glutathione and leukocyte migration mainly when the functionalized drug-loaded nanoparticles were tested, in a lower dose than the free drug. As hypothesized, the experimental data suggest that cholesterol-functionalized carvedilol-loaded PLGA nanoparticles can be a novel and promising approach in the inflammation-induced cancer therapy since showed anti-inflammatory, antioxidant, and antitumor effects.Graphical abstractRadiolog

Effective combination of liposome-targeted chemotherapy and PD-L1 blockade of murine colon cancer

Therapeutic cancer drug efficacy can be limited by insufficient tumor penetration, rapid clearance, systemic toxicity and (acquired) drug resistance. The poor therapeutic index due to inefficient drug penetration and rapid drug clearance and toxicity can be improved by using a liposomal platform. Drug resistance for instance against pemetrexed, can be reduced by combination with docetaxel. Here, we developed a specific liposomal formulation to simultaneously deliver docetaxel and pemetrexed to enhance efficacy and safety. Hydrophobic docetaxel and hydrophilic pemetrexed were co-encapsulated into pH-sensitive liposomes using a thin-film hydration method with high efficiency. The physicochemical properties, toxicity, and immunological effects of liposomes were examined in vitro. Biodistribution, anti-tumor efficacy, and systemic immune response were evaluated in vivo in combination with PD-L1 immune checkpoint therapy using two murine colon cancer models. In cellular experiments, the liposomes exhibited strong cytotoxicity and induced immunogenic cell death. In vivo, the treatment with the liposome-based drug combination inhibited tumor development and stimulated immune responses. Liposomal encapsulation significantly reduced systemic toxicity compared to the delivery of the free drug. Tumor control was strongly enhanced when combined with anti-PDL1 immunotherapy in immunocompetent mice carrying syngeneic MC38 or CT26 colon tumors. We showed that treatment with liposome-mediated chemotherapy of docetaxel and pemetrexed combined with anti-PD-L1 immunotherapy is a promising strategy for the treatment of colon cancers.Horizon 2020 (H2020

Addressing cultural, racial and ethnic discrepancies in guideline discordant gestational weight gain: a systematic review and meta-analysis

Objective To systematically review the literature and describe the discrepancies in achieving the 2009 Institute of Medicine (IOM) gestational weight gain (GWG) guidelines across cultures. Methods Ten databases were searched from inception to April 2018. Observational cohort studies were included that examined adult women; reported on a measure of culture; compared cultural groups, and reported on GWG. Articles were broken down into papers that used the current 2009 IOM GWG guidelines and those that used others. A meta-analysis was conducted for studies using the 2009 guidelines examining the prevalence of discordant GWG across cultural groups. Results The review included 86 studies. Overall, 69% of women experienced discordant GWG irrespective of culture. White women experienced excessive GWG most often, and significantly more than Asian and Hispanic women; Black women had a higher prevalence of excessive GWG than Hispanic and Asian women; however, this difference was not significant. Conclusions The majority of women experience excessive GWG, with White women experiencing this most often. Culturally diverse GWG guidelines are needed to individualize antenatal care and promote optimal maternal-fetal health outcomes across cultural groups