953 resultados para federal reserve


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The smart grid concept is a key issue in the future power systems, namely at the distribution level, with deep concerns in the operation and planning of these systems. Several advantages and benefits for both technical and economic operation of the power system and of the electricity markets are recognized. The increasing integration of demand response and distributed generation resources, all of them mostly with small scale distributed characteristics, leads to the need of aggregating entities such as Virtual Power Players. The operation business models become more complex in the context of smart grid operation. Computational intelligence methods can be used to give a suitable solution for the resources scheduling problem considering the time constraints. This paper proposes a methodology for a joint dispatch of demand response and distributed generation to provide energy and reserve by a virtual power player that operates a distribution network. The optimal schedule minimizes the operation costs and it is obtained using a particle swarm optimization approach, which is compared with a deterministic approach used as reference methodology. The proposed method is applied to a 33-bus distribution network with 32 medium voltage consumers and 66 distributed generation units.

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Nowadays 70% of the world's rubber supply is synthesized artificially. The process involved in its manufacture is vulcanization which requires many chemical substances for speeding the process, as antioxidants to prevent deterioration of rubber, or others. These substances may constitute important sensitizers and thus be responsible for dermatological diseases like contact dermatitis. The objective of this study is to search for the main sensitizers among these rubber chemicals in a population mostly composed by women of a tropical country and compare the results with the ones obtained from previous studies which tested populations mainly composed by men and on different climates.

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The Federal District of Brazil (DF) lies within the Cerrado biome, where open shrubland (savannas) is interspersed with riverside gallery forests and permanent swamps (veredas). Trypanosoma cruzi-infected native triatomines occur in the area, but the enzootic transmission of trypanosomatids remains poorly characterized. A parasitological survey involving sylvatic triatomines (166 Rhodnius neglectus collected from Mauritia flexuosa palms) and small mammals (98 marsupials and 70 rodents, totaling 18 species) was conducted in 18 sites (mainly gallery forests and veredas) of the DF. Parasites were isolated, morphologically identified, and characterized by PCR of nuclear (mini-exon gene) and kinetoplast DNA (kDNA). Six R. neglectus, seven Didelphis albiventris and one Akodon cursor were infected by trypanosomes; wild reservoir infection is documented for the first time in the DF. kDNA PCR detected T. cruzi in five R. neglectus and mini-exon gene PCR revealed T. cruzi I in isolates from D. albiventris. Parasites infecting one bug yielded T. rangeli KP1+ kDNA amplicons. In spite of the occurrence of T. cruzi-infected D. albiventris (an important wild and peridomestic reservoir) and R. neglectus (a secondary vector displaying synanthropic behavior), a low-risk of human Chagas disease transmission could be expected in the DF, considering the low prevalence infection recorded in this work. The detection of T. rangeli KP1+ associated with R. neglectus in the DF widens the known range of this parasite in Brazil and reinforces the hypothesis of adaptation of T. rangeli populations (KP1+ and KP1-) to distinct evolutionary Rhodnius lineages.

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Hepatitis C virus (HCV) genotypes and subtypes were determined in hemodialysis patients in the Federal District, Brazil, by sequencing of the 5' noncoding (NC) and nonstructural 5B (NS5B) regions. From 761 patients, 66 anti-HCV-positive samples were tested for HCV RNA. All 51 HCV RNA-positive samples by PCR of the 5' NC region were genotyped as genotypes 1 (90.2%) and 3 (9.8%). Subtype 1a (82.3%) was the most prevalent, followed by subtypes 3a (9.8%), 1b (5.9%) and 1a/1b (2.0%). Forty-two samples could be amplified and genotyped in the NS5B region: 38 (90.5%) as genotype 1, subtypes 1a, and 8 (9.5%) as genotype 3, subtype 3a. For the 42 samples sequenced in both regions, the genotypes and subtypes determined were concordant in 100% and 95.2% of cases, respectively. Two samples presented discrepant results, with the 5' NC region not distinguishing correctly the subtypes 1a and 1b. These findings indicate that the HCV genotype 1, subtype 1a, is the most prevalent among hemodialysis patients in the Federal District, Brazil.

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With the aim of identifying the etiology of acute febrile illness in patients suspected of having dengue, yet with non reagent serum, a descriptive study was conducted with 144 people using secondary serum samples collected during convalescence. The study was conducted between January and May of 2008. All the exams were re-tested for dengue, which was confirmed in 11.8% (n = 17); the samples that remained negative for dengue (n = 127) were tested for rubella, with 3.9% (n = 5) positive results. Among those non reactive for rubella (n = 122), tests were made for leptospirosis and hantavirus. Positive tests for leptospirosis were 13.9% (n = 17) and none for hantavirus. Non reactive results (70.8%) were considered as Indefinite Febrile Illness (IFI). Low schooling was statistically associated with dengue, rubella and leptospirosis (p = 0.009), dyspnea was statistically associated with dengue and leptospirosis (p = 0.012), and exanthem/petechia with dengue and rubella (p = 0.001). Among those with leptospirosis, activities in empty or vacant lots showed statistical association with the disease (p = 0.013). Syndromic surveillance was shown to be an important tool in the etiologic identification of IFI in the Federal District of Brazil.

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Vaccination of health care workers is an efficient way to reduce the risk of occupational infection and to prevent nosocomial transmission to vulnerable patients. Despite this, achieving high immunization rates among those professionals is a challenge. We assessed the immunization status of Residents in Pediatrics at the Federal University of São Paulo from June to December 2008. Their immunization records were checked and evaluated according to the Brazilian Immunization Schedule for health care workers. Considering all required vaccines, only 3.1% of the 64 Residents were up-to-date with their immunizations. Influenza was the vaccine with the lowest uptake (3.1%) and measles and rubella were diseases with the highest evidence of immunity (62.5% each). Only 37.5% of Residents had received three hepatitis B vaccine doses with a subsequent serology confirming seroconversion. Moreover, the vast majority of Residents in Pediatrics who were not up-to-date were unaware of the fact. Both medical schools and Pediatric Residence programs should not only offer information but also check vaccination records in an effort to keep their healthcare workers´ vaccinations up-to-date.

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Neurocardiogenic syncope (NCS) is a common clinical entity resulting from an excessive reflex autonomic response, particularly during orthostatism. Treatment options are controversial and of limited effectiveness. Tilt training (TT) is a promising option to treat these patients. However, its mechanism of action and clinical impact remain unclear. OBJECTIVE: To characterize hemodynamic and autonomic responses during a TT program in patients with NCS refractory to conventional measures. METHODS: We studied 28 patients (50% male, mean age 41±14 years) without structural heart disease, with NCS documented by tilt testing. The TT program included 9 tilt sessions (3 times a week, 30 min) (60° - 6 sessions, 70° - 3 sessions), under ECG and blood pressure monitoring combined with home orthostatic self-training and 10° head-up during sleep. Systolic volume, cardiac output, total peripheral resistance, baroreflex sensitivity and heart-rate variability were computed. Patients were reassessed at 1 month and every 6 months for a maximum of 36 months (24±12 months). RESULTS: Over the course of the TT program there was a significant increase in total peripheral resistance (1485±225 vs. 1591±187 dyn·s·cm(-5), p<0.05), with a decrease in standard deviation (206±60 vs. 150±42, p<0.05). During follow-up, syncope recurred in five patients (19%), with a significant reduction in the number of episodes (4.0±3.2/patient in the 12 months before TT vs. 1.4±0.8/patient post-TT, p<0.05). CONCLUSION: In refractory NCS, TT may be an effective therapeutic option, with long-term benefits. These results appear to be due to an increase in vasoconstrictor reserve combined with a reduction in its variance.

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Sôros coletados no Território Federal do Amapá, localidade de Ferreira Gomes, foram, testados para anticorpos neutralizantes de enterovírus Poliovírus 1, 2 e 3 e Coxsackie B1 a B6, em população autóctone. Os resultados apresentados na Tabela 1, indicam alta circulação do vírus da poliomielite na região atingindo-se níveis tão elevados como em escolares do Estado da Guanabara. Em relação a Coxsackie B, alcançaram-se também resultados semelhantes nas duas populações exceto com Coxsackie B., o qual apresentou-se em valôres bem mais altos nos sôros coletados na região norte. Os autores chamam atenção da necessidade de vacinação contra a poliomielite de grandes segmentos da população susceptível em curto prazo, tendo em vista a ampla disseminação das infecções por poliovírus em tôdas as regiões do país onde forem pesquisadas.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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53 amostras de soro, provenientes de Ferreira Gomes, no Amapá, foram testados para antígeno HB Ag e anticorpo HB Ab, com uma positividade de 3,7% para HB Ag, sub-tipo D. Os autores acentuam a necessidade de inquéritos em populações brasileiras a fim de estabelecer os sub-tipos associados à hepatite.

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Em uma amostra de 3137 pessoas, residentes no Distrito Federal, foram detectadas as seguintes hemoglobinas: em 3009(95,92%) HbAA; em 91 (2,90%) HbAS; em 20(0,64%) HbAC; em 8 (0,26%) talassemia beta minor; em 5(0,16%) HbAJ alfa; em 3 (0,09%) HbAM e em 1 (0,03%) talassemia major associada com HbAS. A HbAS têm as seguintes freqüências, quanto ao grupo racial: branco - 1,84%; mulato claro 2,55%; mulato médio-3,68%; mulato escuro - 6,80%; negro -10,43% e mestiço de índio -3,85%.

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Estudo soroepidemiológico realizado em Brasília evidenciou a presença de infecção pelo Cysticercus cellulosae, detectada pelos testes imunoenzimáticos Elisa e imunofluorescência indireta, em 5,2% dos 1122 indivíduos avaliados. Entre os 120 líquidos cefalorraqueanos examinados, provenientes de pacientes que apresentaram sinais sugestivos de neurocisticercose, 16,7% foram reagentes. A prevalência da sorologia reagentefoi 20,4% no grupo de doentes com a hipótese diagnostica de cisticercose, 3,5% no grupo de seus familiares, 5,5% e 0,6% naqueles constituídos de pacientes ambulatoriais com cefaléia e epilepsia, respectivamente; e 0% no grupo controle. A cisticercose prevaleceu nas faixas etárias mais avançadas, nâo havendo predominância de sexo. No diagnóstico imunológico detectaram-se índices de positividoâe que variaram entre os grupos naturais das diversas regiões do país, sendo encontrados 8,1% de indivíduos sororreagentes no Sudeste, 5,8% no Nordeste, 5,3% no Centro-Oeste e 3,5% no Sul do país. Dos fatores epidemiológicos, a ausência de condições sanitárias nas residências, o maior contato com suínos, e o uso de água de rio constituíram os maiores riscos para contrair a moléstia, sendo seu risco relativo de 3,1, 2,2 e 1,8, respectivamente.