A manutenabilidade de uma boa distribuição de partículas é algo fundamental em simulações através do SPH, sendo um dos fatores responsáveis pela estabilidade do sistema e a acurácia do método. Em soluções através do método ISPH (acrônimo em inglês para Incompressible Smoothed Particle Hydrodynamcs) este resultado pode ser alcançado através de uma técnica baseada na introdução de um deslocamento de partículas, de forma a retirá-las de suas trajetórias lagrangeanas. Entretanto, quando diretamente aplicada a escoamentos multifásicos, esta técnica acaba introduzindo um comportamento não físico na interface entre fluidos, resultando em um incorreto posicionamento da interface, e prejudicando a simulação. Neste trabalho, propomos uma correção baseada em uma função suave, definida inicialmente como a distância normal à interface. Testes numéricos mostram que esta correção consegue recuperar a correta posição da interface. Finalmente, um estudo sobre a conservação de massa desta técnica é apresentado.

The maintainability of a good particle distribution is of prior importance toSPH (Smoothed Particle Hydrodynamics) simulations, since it affects both stability and accuracy of the numerical results. When using ISPH (Incompressible SPH), the particle distribution can be improved by dislocating particles away from their Lagrangian trajectories. However, when applying this technique to multiphase flows, the correct position of the interface between fluids is disturbed, resulting in unphysical flow behavior. In this work, we propose a correction, based upon a constructed smooth distance function. Numerical tests show that this correction can recover the expected position of the interface. Finally, issues regarding mass conservation are assessed and reported.

We report a fast (less than 3 h) and cost-effective melting temperature assay method for the detection of single-nucleotide polymorphisms in the MBL2 gene. The protocol, which is based on the Corbett Rotor Gene real time PCR platform and SYBR Green I chemistry, yielded, in the cohorts studied, sensitive (100%) and specific (100%) PCR amplification without the use of costly fluorophore-labeled probes or post-PCR manipulation. At the end of the PCR, the dissociation protocol included a slow heating from 60º to 95ºC in 0.2ºC steps, with an 8-s interval between steps. Melting curve profiles were obtained using the dissociation software of the Rotor Gene-3000 apparatus. Samples were analyzed in duplicate and in different PCR runs to test the reproducibility of this technique. No supplementary data handling is required to determine the MBL2 genotype. MBL2 genotyping performed on a cohort of 164 HIV-1-positive Brazilian children and 150 healthy controls, matched for age and sex and ethnic origin, yielded reproducible results confirmed by direct sequencing of the amplicon performed in blind. The three MBL2 variants (Arg52Cys, Gly54Asp, Gly57Glu) were grouped together and called allele 0, while the combination of three wild-type alleles was called allele A. The frequency of the A/A homozygotes was significantly higher among healthy controls (0.68) than in HIV-infected children (0.55; P = 0.0234) and the frequency of MBL2 0/0 homozygotes was higher among HIV-1-infected children than healthy controls (P = 0.0296). The 0 allele was significantly more frequent among the 164 HIV-1-infected children (0.29) than among the 150 healthy controls (0.18; P = 0.0032). Our data confirm the association between the presence of the mutated MBL2 allele (allele 0) and HIV-1 infection in perinatally exposed children. Our results are in agreement with the literature data which indicate that the presence of the allele 0 confers a relative risk of 1.37 for HIV-1 infection through vertical transmission.

Experimentos de campo foram conduzidos entre maio e outubro de 2000 para determinar a eficiência de diversos inseticidas para o controle de Tuta absoluta e Helicoverpa zea e o impacto desses produtos sobre a emergência do parasitóide Trichogramma pretiosum. Os inseticidas testados, bem como as doses em g i.a./ha foram: metoxifenozide (120; 144), clorpirifós (540; 675), tiacloprid (72; 96) e triflumuron (144). O delineamento experimental foi de blocos ao acaso com oito tratamentos (inseticidas e testemunha) e cinco repetições, com 40 plantas/parcela. Frutos de tomate foram coletados aos 58, 80 e 87 dias após o transplante das mudas para a determinação da percentagem de frutos danificados pelos insetos. O impacto dos inseticidas sobre T. pretiosum foi avaliado mediante a coleta de 20 ovos de H. zea por parcela aos 61 dias após o transplante, onde foi realizada a avaliação da emergência do parasitóide. Todos os inseticidas reduziram significativamente os danos causados por H. zea. Contudo, nenhum deles foi eficiente para o controle de T. absoluta. Metoxifenozide e clorpirifós (540) não reduziram significativamente o número de ovos parasitados por T. pretiosum quando comparados à testemunha.

Field studies were conducted from May to October 2000 to determine the effectiveness of several insecticides in controlling Tuta absoluta and Helicoverpa zea and their impact on emergence of the parasitoid Trichogramma pretiosum. The insecticides tested were: methoxyfenozide (120; 144), clorpirifós (540; 675), tiacloprid (72; 96) and triflumuron (144). Application rates of all insecticides are expressed as g a.i./ha. The experiment was designed as randomized complete block with eight treatments (insecticides and untreated plots) with five replications. Tomato fruits were harvested 58; 80 and 87 days after transplanting and the percentage of damaged fruits by both pests determined. The impact of insecticides on T. pretiosum survival was determined collecting 20 eggs of H. zea/plot 61 days after transplanting and the percentage of emerged parasitoid determined. All insecticides reduced significantly the damage caused by H. zea whereas none of the products were effective in controlling T. absoluta. Methoxyfenozide and clorpirifós (540) did not reduce significantly the number of eggs parasitized by T. pretiosum when comparared with untreated ones.

OBJETIVO: Determinar uma associação entre o quadro clínico pré-operatório e os resultados das culturas de bile e da parece vesicular. CASUÍSTICA E MÉTODOS: Foram estudadas 28 variáveis considerando-se história clínica, exame físico e investigação laboratorial em 38 doentes portadores de colecistite aguda calculosa, submetidos à cirurgia de urgência. Este estudo prospectivo foi realizado em 19 meses, entre novembro de 1995 a maio de 1997. Foram realizadas culturas para agentes anaeróbios e aeróbios, em três diferentes meios de cultura (BACTEC 9240, BHI e HEMOBAC). RESULTADOS: Foram isoladas bactérias em pelo menos um meio de cultura em 68,2% dos doentes. Pela análise univariada, foram identificadas cinco variáveis pré-operatórias como preditivas de bacteriobilia: idade acima de 55 anos, temperatura diferencial axilo-retal maior do que 0,4°C, leucocitose acima de 12000 cels/mm³, neutrofilia acima de 75% e neutrófilos bastonetes acima de 4%. Devido ao pequeno tamanho da amostra, não pôde ser observada significância estatística por regressão logística, embora pudesse ser observada em 98% uma tendência para determinação pré-operatória dos indivíduos com cultura positiva por meio do modelo baseado na idade e porcentagem de neutrófilos bastonetes. Pela análise em conjunto dos fatores preditivos, pôde-se observar que doentes com mais de um fator preditivo têm uma possibilidade significantemente maior para cultura positiva, quando comparado com aqueles com fator preditivo de bacteriobilia. CONCLUSÃO: Conclui-se, portanto, que pela utilização de dados facilmente disponíveis em doentes com colecistite aguda calculosa, a bacteriobilia pode ser previsível no pré-operatório,.

OBJECTIVE: to determine an association between the preoperative clinical status and the result of bile and gallbladder wall cultures. MATERIAL AND METHODS: 28 variables regarding history, physical examination and laboratorial assessment in 38 patients with acute calculosis cholecystitis submitted to urgency surgery were prospectively studied during a 19-month period, between November 1995 and May 1997. Cultures for aerobic and anaerobic agents from both the gallbladder wall and the bile were performed, in three different culture media (BACTEC 9240, BHI and HEMOBAC). RESULTS: bacteria were isolated in at least one culture medium, in 68.2% of the patients. At univariate analysis, five preoperative factors were identified as predictors of bactibilia: over 55 years of age, a greater than 0.4°C difference in the axillary-rectal temperature, a greater than 12.000 cels/m³ blood leukocyte count, a greater than 75% neutrophil percentage and a greater than 4% rod neutrophil percentage. Owing to the small sample size, statistical significance of the series could not be noted by logistic regression, although a trend to preoperative determination could be observed in 98% of the subjects with positive culture, by means of the model based on age and percentage of rod neutrophil. By analyzing predictive factors jointly, it was noted that patients with more than one predictive factor have a significantly greater possibility to yelding positive culture when compared to those with up to one predictive factor for bactibilia. CONCLUSIONS: We concluded that, in patients with acute calculosis cholecystitis, bactibilia may be predicted yet at the preoperative period, by using simple and easily obtained data.

In the present work we describe a method which allows the incorporation of surface tension into the GENSMAC2D code. This is achieved on two scales. First on the scale of a cell, the surface tension effects are incorporated into the free surface boundary conditions through the computation of the capillary pressure. The required curvature is estimated by fitting a least square circle to the free surface using the tracking particles in the cell and in its close neighbors. On a sub-cell scale, short wavelength perturbations are filtered out using a local 4-point stencil which is mass conservative. An efficient implementation is obtained through a dual representation of the cell data, using both a matrix representation, for ease at identifying neighbouring cells, and also a tree data structure, which permits the representation of specific groups of cells with additional information pertaining to that group. The resulting code is shown to be robust, and to produce accurate results when compared with exact solutions of selected fluid dynamic problems involving surface tension.

Capsular polysaccharide antigen (AgPC) of Cryptococcus neoformans was detected by latex agglutination technique (LA) in cerebrospinal fluid and serum of patients with AIDS during their first central nervous system manifestation of the disease. Direct mycological examination and culture were used as controls. Sensitivity was 100% by LA allowing an early specific treatment of cryptococcosis. Initial titres of AgPC in such patients can be > 1000000 and it appears that when such titres are present in the serum they are related to mortality during treatment. Surviving patients showed positivity of the direct mycological examination and AgPC of C. neoformans in cerebrospinal fluid and sera even after treatment and clinical recovery.

Antígeno del polisacárido capsular (Ag PC) de Cryptococcus neoformans fue detectado por la técnica de aglutinación de latex (AL) en LCR y suero de pacientes con Sindrome de Inmunodeficiencia Adquirida (SIDA) y primer episodio de neurocriptococosis, usando como patrón el examen micológico (examen directo y cultivo) de LCR. Se obtuvo una sensibilidad del 100% de AL para detectar AgPC de C. neoformans, el cual por su rápidez permite tratamiento específico precoz. Títulos iniciales de AgPC de la levadura en esos pacientes pueden ser > 1.000.000, pareciendo que cuando esos títulos están presentes en suero, se relacionan con mortalidad durante el tratamiento. En los pacientes que sobrevivieron se observó que el examen micológico directo y AgPC de C. neoformans, en LCR y suero, permanecen positivos aún después de tratamiento y mejoría clínica del paciente.

Vinte e dois pacientes alcoólatras crônicos foram submetidos a exame clínico neurológico e biópsia muscular. Eles apresentavam graus variáveis de fraqueza muscular proximal (cinturas escapular e pélvica), tendo um deles evoluído com quadro agudo de miopatia (avaliação pelo 'Manual Muscle Test', MMT). A principal alteração histológica observada é melhor evidenciada pela coloração da ATPase: atrofia muscular (95,3%), predominando nas fibras do tipo II A (71,4%) e, em 76% dos casos, alteração da imagem em mosaico à custa de agrupamentos de fibras musculares de mesmo tipo histoquímico ('type-grouping'). Secundariamente, em 63% dos casos, observa-se proliferação mitocondrial e conseqüente acúmulo lipídico intra-sarcoplasmático. No caso de instalação aguda da fraqueza muscular, o substrato anátomo-patológico é completamente diferente: presença de mlosite, predominantemente intersticial, caracterizada por infiltrado linfoplasmocitário e numerosas imagens de necrose tipo degeneração cérea de Zencker. Baseando-se em critérios histológicos, nossos dados sugerem que: a principal gênese da fraqueza muscular observada em pacientes alcoólatras crônicos tem natureza neurogênica (polineuropatia alcoólica); a atuação tóxica direta do etanol sobre o músculo esquelético está intimamente relacionada ao metabolismo mitocondrial; a chamada miopatia aguda alcoólica tenha etiologia inflamatória, do tipo viral.

Twenty-two chronic acoholic patients were assessed by neurologic examination and muscle biopsy. The patients manifested proximal muscular weakness to a variable extent. One case presented as an acute bout of myopathy, according to the Manual Muscle Test, MMT. The most prominent histologic feature observed was muscle atrophy (95.3%) better evidenced through the ATPase stain with the predominance of type II A fibers (71.4%). Lack of the mosaic pattern (type grouping) seen in 76% of the cases and an important mitochondrial proliferation with intrasarcoplasmatic lipid accumulation in 63% of the patients. In case of acute presentation of muscle weakness the. pathological substrate is quite different, i.e. presence of myositis mainly interstitial characterized by lymphoplasmocytic infiltrate and several spots of necrosis like Zencker degeneration. Based on histologic criteria, our data suggest that: the main determinant of muscle weakness seen in chronic alcoholic patients is neurogenic in origin (alcoholic polineuropathy); the direct toxic action of ethanol under the skeletal muscle is closely related to the mitochondrial metabolism; the so-called acute alcoholic myopathy has probably viral etiology.