This study presents efficient geometric parameterisation techniques for the continuation power flow. The Jacobian matrix singularity is eliminated by the addition of the line equations which pass through the points in the plane determined by the variables loading factor and the sum of nodal voltage magnitudes, or angles, of all system buses. These techniques enable the complete tracing of P-V curves and the computation of the maximum loading point for any power system, including those with voltage instability problems that have the strong local characteristics, for which the global parameterisation techniques are considered inadequate. An efficient criterion to change the set of lines, based on the analysis of the total power mismatch evolution, is also defined. The obtained results show that the characteristics of Newton's conventional method are preserved and the convergence region around the Jacobian matrix singularity is enhanced. The computational time required to trace the P-V curve can also be reduced, without losing robustness, when the Jacobian matrix is updated only after the system undergoes a significant change.

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This study aimed to develop a fuzzy mathematical model to estimate the impacts of global warming on the vitality of Laelia purpurata growing in different Brazilian environmental conditions. In order to develop the mathematical model was considered as intrinsic factors the parameters: temperature, humidity and shade conditions to determine the vitality of plants. Fuzzy model results could accurately predict the optimal conditions for cultivation of Laelia purpurata in several sites of Brazil. Based on fuzzy model results, we found that higher temperatures and lacking of properly shading can reduce the vitality of orchids. Fuzzy mathematical model could precisely detect the effect of higher temperatures causing damages on vitality of plants as a consequence of global warming.

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RESUMO: Os tumores malignos do canal anal e do anus são muito raros, não ultrapassam 2% de todos os tumores do colo, reto e anus; segundo os principais levantamentos os melanomas não ultrapassam a incidência de 0,1 a 1,2% dos tumores malignos. Os autores descrevem 2 casos de melanoma, discutindo os principais dados da literatura, enfocando os aspectos diagnósticos, tratamento, evolução e prognostico. Os indicies de cura s são baixos e com elevados índices de mortalidade a curto prazo. Descritores INTRODUÇÃOA pele é a principal localização do melanoma, porém outros locais podem ser afetados, como cavidade oral, nasal, fígado, baço e intestino seja de forma primaria ou secundaria (metastaticos).O melanoma maligno anorretal apresenta baixa incidência, sendo um tumor pouco freqüen-te; representa 0,4% -1,6% de todos os melanomas e 1% dos tumores do canal anal.(1-10) , a faixa etária prevalente é entre a sexta e oitava décadas de vida (5,(14)(15)(16) . Quanto à localização, os tumores podem localizar-se na região retal (muito rara), anorretal e anal, sendo estas duas as apresentações mais freqüentes.O objetivo desse trabalho é revisar a literatura sobre o assunto, e relatar dois casos de melanoma anorretal em duas pacientes do sexo feminino, com idades de 53 e 61 anos, diagnosticados no serviço de cirurgia do aparelho digestivo da Faculdade de Medicina de Botucatu. RELATO 1A.J.O.C. 61 anos, sexo feminino, paciente há 9 meses com história de episódios de enterorragia. Caracterizava o sangramento como sendo vivo após as evacuações, manchando o vaso sanitário e o papel higiênico, com perda ponderal de 10kg no período associado à inapetência, sem outros sintomas associados. Há 2 meses foi submetida a histerectomia vaginal, durante a qual, durante o posicionamento o ginecologista visualizou lesão vegetante em canal anal, sendo então encaminhada ao nosso serviço. A paciente foi submetida à retossigmoidoscopia onde foi evidenciada lesão vegetante endurecida, medindo cerca de 3 cm de extensão, a 2cm da borda anal, hiperpigmentada escurecida, aderida a planos profundos (figura 1). A biópsia foi compatível com Melanoma de Canal Anal comprovada por imuno-histoquímica.Nos exames de estadiamento, a colonoscopia evidenciando apenas doença diverticular dos cólons em descendente e sigmóide, Rx tórax normal, CT abdomi- RELATO DE CASOS __________________________________________________

PURPOSE: Malnutrition is prevalent in patients with advanced liver disease (LD) related to multifactorial causes. Fluid retention can underestimate the nutritional status based on anthropometric measures. We evaluated nutritional indicators and body composition (BC) in patients with liver cirrhosis and correlated them with LD severity. METHODS:Forty three patients with LD enrolled for liver transplantation were evaluated by Anthropometric measures, subjective evaluation (Global Assessment of Nutritional Status -SGA) and biochemical indicators. Single-frequency electrical bioimpedance (SFE-BIA) was used to evaluate body composition (BC). It measured resistance (R), reactance (Xc) and the phase angle (PA). LD severity was estimated by Child-Pugh and Meld criteria (Model for End-Stage Liver Disease). RESULTS:Child-Pugh index between patients was 7.11±1.70 and Meld was 12.23±4.22. Arm Circumference, Arm Muscle Circumference and Arm Muscle Area, SGA, hemoglobin, hematocrit and albumin showed better correlation with disease severity. Xc and PA showed correlation both with Meld and Child-Pugh score when BC were evaluated. PA was depleted in 55.8% of the patients. CONCLUSIONS:Diagnosis of malnutrition varied according to the method. Global assessment of nutritional status showed better correlation with disease severity than with objective methods. Single-frequency electrical bioimpedance for body composition analysis in cirrhotic patients must be cautiously used; however, primary vectors seems to be valid and promising in clinical practice.

ABSTRACT. Background. Necrotizing enterocolitis (NEC) is a life-threatening condition of the neonatal age, which frequently requires surgical intervention. After extensive bowel resection, a small proportion of these patients may develop chronic short gut syndrome (SGS) and require chronic total parenteral nutrition (TPN) use. Intestinal transplantation has been performed in these patients as a life-saving option.This study reviews our experience with intestinal transplantation for SGS attributable to NEC emphasizing the mode of presentation, natural history, timing, and outcome.Methods. A retrospective chart review was performed for all pediatric patients who underwent small bowel transplantation for NEC at the University of Miami between August 1994 and March 1999.

This paper presents an efficient geometric parameterization technique for the continuation power flow. It was developed from the observation of the geometrical behavior of load flow solutions. The parameterization technique eliminates the singularity of load flow Jacobian matrix and therefore all the consequent problems of ill-conditioning. This is obtained by adding equations lines passing through the points in the plane determined by the loading factor and the total real power losses that is rewritten as a function of the real power generated by the slack bus. An automatic step size control is also provided, which is used when it is necessary. Thus, the resulting method enables the complete tracing ofP-Vcurves and the computation of maximum loading point of any electric power systems. Intending to reduce the CPU time, the effectiveness caused by updating the Jacobian matrix is investigated only when the system undergoes a significant change. Moreover, the tangent and trivial predictors are compared with each other. The robustness and simplicity as well as the simple interpretation of the proposed technique are the highlights of this method. The results obtained for the IEEE 300-bus system and for real large systems show the effectiveness of the proposed method.