34 research outputs found

    Solución de la ecuación de Rayleigh-Plesset por medio del método del elemento finito

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    In this work we present numerical solutions of the Rayleigh-Plesset equation which describes the evolution of cavitating bubbles. In order to do that, we consider FEMG (Finite Element Method Galerkin); this simulation is performed for an inviscid and incompressible fluid in an uniform temperature field with constant surface tension, and the cavitation model into the which the pressure inside bubbles is equal to the fluid vapor pressure. Thus, in this problem is considered the Dirichlet boundary problem, and we obtained criteria for the boundary conditions at the cavitation phenomenon through to the which give rise to the bubble growing.En este trabajo presentamos soluciones numéricas de la ecuación de Rayleigh-Plesset que describe la evolución de las burbujas de cavitación. Para hacer eso, consideramos FEMG (Método de elementos finitos Galerkin); Esta simulación se realiza para un fluido invisible e incompresible en un campo de temperatura uniforme con tensión superficial constante, y el modelo de cavitación en el que la presión dentro de las burbujas es igual a la presión de vapor del fluido. Por lo tanto, en este problema se considera el problema de límite de Dirichlet, y obtuvimos criterios para las condiciones de contorno en el fenómeno de cavitación a través del cual dan lugar al crecimiento de la burbuja

    Programa de explotación y ajuste tecnológico: Distrito de Montería

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    El objetivo de este ajuste tecnológico es el aumento de la producción y productividad por unidad de superficie para los siguientes sistemas de producción en los Distritos de Montería y Sincelejo : maíz asociado con ñame e intercalado con yuca en suelos livianos y pesados, maíz asociado con ñame, arroz de secano, plátano y yuca. Se presentan unos supuestos generales y luego el ajuste tecnológico en cada uno de los cultivos asociados o limpios así : maíz asociado con ñame e intercalado con yuca (se realizaron 20 experimentos de campo para probar las hipótesis planteadas en cuanto a variedades, fertilización y densidad de población). Producción de maíz asociado con ñame, arroz de secano, producción de maíz limpio, fertilización nitrogenada y densidad de población en maíces mejorados y regionales, ajuste tecnológico en el sistema de producción de plátano, producción de tabaco negro, ajuste tecnológico en el cultivo de la yuca. Se presenta el presupuesto en el ajuste tecnológico en los distritos mencionados al comienz

    Quantificação de fatores de crescimento na pele de equinos tratada com plasma rico em plaquetas

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    O plasma rico em plaquetas (PRP) é um produto derivado da centrifugação do sangue total, sendo rico em fatores bioativos, como os de crescimento. Apesar da ampla utilização em processos cicatriciais, há controvérsia sobre a eficácia da terapia na cicatrização cutânea. O objetivo desse estudo foi quantificar e comparar a concentração dos fatores TGF-β1 e PDGF-BB no PRP, plasma sanguíneo e pele, durante diferentes fases do processo de cicatrização da pele tratada ou não com PRP. Foram utilizados sete equinos machos castrados, mestiços, hígidos, com idade entre 16 e 17 (16,14±0,63) anos. Três lesões em formato quadrangular (6,25cm²) foram produzidas cirurgicamente nas regiões glúteas direita e esquerda de todos os animais. Doze horas após indução das feridas, 0,5mL do PRP foi administrado em cada uma das quatro extremidades das feridas de uma das regiões glúteas (Grupo tratado = GT), escolhida aleatoriamente. A região contralateral foi utilizada como controle (GC). As feridas foram submetidas à limpeza diária com água Milli Q, e amostras foram obtidas mediante biópsias realizadas com Punch de 6mm. Foram obtidas seis biópsias de pele, sendo a primeira realizada logo após a produção da ferida (T0), e as demais com 1 (T1) 2 (T2) 7 (T3) e 14 (T4) dias após a indução da lesão. A sexta biópsia (T5) foi obtida após completo fechamento da pele, que ocorreu aproximadamente aos 37 dias (36,85±7,45, GC; 38,85±6,46, GT). Também foram obtidas amostras de sangue com EDTA em todos os tempos mencionados. A quantificação dos fatores de crescimento TGF-β1 e PDGF-BB na pele, PRP e plasma sanguíneo foi realizada pela técnica ELISA. Os dados foram analisados estatisticamente pelo teste t, correlação de Pearson e regressão, utilizando nível de significância de 5%. Não houve diferença entre os grupos, nos valores dos dois fatores de crescimento mensurados na pele, nos diferentes tempos. Também não houve correlação entre a quantidade dos fatores de crescimento presentes na pele e no plasma. Por outro lado, correlação positiva foi observada entre PRP e pele no grupo tratado, para os fatores de crescimento TGF-β1 (r=0,31) e PDGF-BB (r=0,38), bem como entre ambos os fatores de crescimento presentes no PRP (r=0,81). Considerando as concentrações dos fatores de crescimento no T0, os maiores valores cutâneos (p<0,05) do TGF-β1, em ambos os grupos, ocorreram nos tempos T3 e T5. Valores mais elevados (p<0,05) do PDGF-BB ocorreram no T4 (GT) e T5 (GC). No plasma não houve alteração nas concentrações desses fatores em relação ao T0, o que sugere que o PRP não acarreta efeito sistêmico, quando os procedimentos adotados na presente pesquisa são utilizados. A administração local de PRP no volume estudado, 12 h após indução cirúrgica de ferida cutânea na região glútea de equinos não ocasiona maiores concentrações dos fatores de crescimento TGF-β1 e PDGF-BB no plasma sanguíneo e pele, durante o processo de cicatrização

    Genetic Testing to Inform Epilepsy Treatment Management From an International Study of Clinical Practice

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    IMPORTANCE: It is currently unknown how often and in which ways a genetic diagnosis given to a patient with epilepsy is associated with clinical management and outcomes. OBJECTIVE: To evaluate how genetic diagnoses in patients with epilepsy are associated with clinical management and outcomes. DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective cross-sectional study of patients referred for multigene panel testing between March 18, 2016, and August 3, 2020, with outcomes reported between May and November 2020. The study setting included a commercial genetic testing laboratory and multicenter clinical practices. Patients with epilepsy, regardless of sociodemographic features, who received a pathogenic/likely pathogenic (P/LP) variant were included in the study. Case report forms were completed by all health care professionals. EXPOSURES: Genetic test results. MAIN OUTCOMES AND MEASURES: Clinical management changes after a genetic diagnosis (ie, 1 P/LP variant in autosomal dominant and X-linked diseases; 2 P/LP variants in autosomal recessive diseases) and subsequent patient outcomes as reported by health care professionals on case report forms. RESULTS: Among 418 patients, median (IQR) age at the time of testing was 4 (1-10) years, with an age range of 0 to 52 years, and 53.8% (n = 225) were female individuals. The mean (SD) time from a genetic test order to case report form completion was 595 (368) days (range, 27-1673 days). A genetic diagnosis was associated with changes in clinical management for 208 patients (49.8%) and usually (81.7% of the time) within 3 months of receiving the result. The most common clinical management changes were the addition of a new medication (78 [21.7%]), the initiation of medication (51 [14.2%]), the referral of a patient to a specialist (48 [13.4%]), vigilance for subclinical or extraneurological disease features (46 [12.8%]), and the cessation of a medication (42 [11.7%]). Among 167 patients with follow-up clinical information available (mean [SD] time, 584 [365] days), 125 (74.9%) reported positive outcomes, 108 (64.7%) reported reduction or elimination of seizures, 37 (22.2%) had decreases in the severity of other clinical signs, and 11 (6.6%) had reduced medication adverse effects. A few patients reported worsening of outcomes, including a decline in their condition (20 [12.0%]), increased seizure frequency (6 [3.6%]), and adverse medication effects (3 [1.8%]). No clinical management changes were reported for 178 patients (42.6%). CONCLUSIONS AND RELEVANCE: Results of this cross-sectional study suggest that genetic testing of individuals with epilepsy may be materially associated with clinical decision-making and improved patient outcomes

    Author Correction: One sixth of Amazonian tree diversity is dependent on river floodplains

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    Mapping density, diversity and species-richness of the Amazon tree flora

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    Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

    Consistent patterns of common species across tropical tree communities

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    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees

    Abscesos pleurales producidos por Staphylococcus aureus y Streptococcus spp. beta-hemolítico como secuela de pleuroneumonía en un caballo: reporte de un caso

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    Pleural abscesses are a frequent complication in horses with pleuropneumonia. Their treatment is not easy, and requires time and it is expensive. A 13 years old creole argentine gelding presented a severe pleuropneumonia subsequently complicated with pleural abscess. The use of nonsteroidal antiinflammatory drugs (fenylbutazone), an aggressive antibiotherapy (ceftiofur, ampicillin, and gentamicin), echoguide drainage and lavage with yodopovidone to 0.05% of the abscesses permitted the successful recuperation of the patient of this case report.Los abscesos pleurales son una complicación frecuente en caballos con pleuroneumonía. Su tratamiento resulta difícil, requiere tiempo y dinero. Un caballo criollo argentino, castrado, de 13 años de edad presentó una pleuroneumonía grave que posteriormente se complicó con abscesos pleurales. El uso de anti-inflamatorios no esteroidales (fenilbutazona), una antibioterapia agresiva (ceftiofur, ampicilina y gentamicina), el drenaje eco-guiado y el lavado de los abscesos con una solución de yodopovidona al 0.05% permitió la recuperación exitosa del paciente de este reporte

    Plasmocitoma extramedular nasal en un perro

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    Se describe un caso de plasmocitoma nasal en un canino, macho entero, de raza Akita de 30 Kg de peso y veintiún meses de edad, con historia de epistaxis unilateral crónica. Se practicó examen clínico y biopsia de la neoplasia visible en la cavidad nasal izquierda. La ubicación y extensión del tumor fue determinada mediante tomografía computarizada de cabeza y cuello. Se realizaron análisis histopatológico e inmunohistoquímico (IHQ) del tejido tumoral. La tomografía computarizada evidenció una masa con densidad de tejido blando de 10 cm de longitud x 3.5 cm de diámetro y escasa captación de medio de contraste, que comprometía en su totalidad la cavidad nasal derecha y parte de la porción posterior de la coana izquierda. El análisis histopatológico reveló numerosas células redondas pleomórficas con poco citoplasma, rodeadas por trama escasa de tejido conectivo y bajo índice mitótico. En el examen IHQ la muestra fue negativa a los antígenos CD3 y CD20 para linfocitos T y B, respectivamente. Los hallazgos clínicos y de la tomografía computarizada, así como los resultados del análisis histopatológico del tejido tumoral, fueron compatibles con un plasmocitoma extramedular nasal de bajo grado de malignidad
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