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Abstract Increasing the power rating of electric vehicles (EV) fast charging stations to reduce charging times is considered critical to accelerate the adoption of electric vehicles. Besides increasing the power, other drivers pushing the development of EV fast chargers include the improvement of efficiency and reliability. Partial power converters (PPC) have emerged as an interesting option for some of the power converter stages in fast charging stations due to their potential to increase efficiency and power rating. However, some PPCs operate as switched autotransformers by using high frequency (HF) isolation transformers but without providing galvanic isolation. This is a drawback due to cost, size and losses introduced by the transformer. This paper presents a transformerless DC–DC Type I step‐up PPC for a DC–DC regulation converter for EV fast charging stations. The proposed converter replaces the transformer commonly used in Type I PPC by an impedance network, resulting in a more efficient, cheaper, and less complex converter option. This concept is verified through simulations and experimentally validated with a laboratory prototype.

Space instruments that operate in the THz range can enable unique measurements for a better understanding of the chemical and physical processes taking place in our Universe. One such application of this technology is a compact 2.06 THz receiver that can measure the ionized oxygen line to determine wind velocity in Earth's upper atmosphere. Metal machined waveguide circuits have long been utilized to build and demonstrate functional receivers in the submillimeter-wave range. However, as the operational frequency is increased, extremely challenging requirements are placed on metal machining in terms of the required precision, surface roughness, and alignment tolerance. This work describes the design and implementation of the first-of-its-kind, vertically-integrated, 2-THz Schottky diode mixer using precise silicon micromachine technology. A traditional e-plane split waveguide package is re-designed to utilize the three-dimensional (3-D) capability of stacking silicon micromachined parts. The silicon microfabrication process has been optimized to produce smooth and precise features for packaging a 2 THz subharmonic GaAs Schottky diode mixer, providing surface roughness better than 1-micron rms with less than 5% variation on critical dimensions. The subharmonic mixer and a fully solid-state local oscillator (LO) chain is currently being implemented to validate silicon micromachining for THz packaging. The impact of micromachining variation on mixer performance is explored through simulations over a range of dimensions on the most sensitive regions of the Si module.

Abstract Central nervous system (CNS) infections are important causes of morbidity and mortality worldwide. In Bolivia, aetiologies, case fatality, and determinants of outcome are poorly characterised. We attempted to investigate such parameters to guide diagnosis, treatment, prevention, and health policy. From Nov-2017 to Oct-2018, we prospectively enrolled 257 inpatients (20.2% HIV-positive patients) of all ages from healthcare centers of Cochabamba and Santa Cruz, Bolivia with a suspected CNS infection and a lumbar puncture performed. Biological diagnosis included classical microbiology, molecular, serological and immunohistochemical tests. An infectious aetiology was confirmed in 128/257 (49.8%) inpatients, including, notably among confirmed single and co-infections, Cryptococcus spp. (41.7%) and Mycobacterium tuberculosis (27.8%) in HIV-positive patients, and Mycobacterium tuberculosis (26.1%) and Streptococcus pneumoniae (18.5%) in HIV-negative patients. The total mortality rate was high (94/223, 42.1%), including six rabies cases. In multivariate logistic regression analysis, mortality was associated with thrombocytopenia (Odds ratio (OR) 5.40, 95%-CI 2.40–11.83) and hydrocephalus (OR 4.07, 95%-CI 1.35–12.23). The proportion of untreated HIV patients, late presentations of neurotuberculosis, the rate of pneumococcal cases, and rabies patients who did not benefit from a post-exposure prophylaxis, suggest that decreasing the burden of CNS infections requires reinforcing health policy regarding tuberculosis, rabies, S. pneumoniae vaccination, and HIV-infections.

Abstract Background Latino fathers may play important roles in adolescents’ physical activity and screen time. However, informant discrepancies regarding paternal activity parenting practices may challenge studies supporting evidence-based applications. This study examined Latino adolescent-father discrepancies in reporting paternal activity parenting practices, types of discrepancies by participant characteristics, and associations between discrepancy types and adolescents’ physical activity and screen time. Methods The sample for this cross-sectional study included Latino early adolescents and their fathers (n = 138 dyads) from baseline data collected for a family-centered, healthy lifestyle intervention in a metropolitan area. In parallel measures, Latino adolescents and fathers reported paternal activity parenting practices related to expectation or allowance, behavioral modeling, and providing opportunities for physical activity or screen time. Level of agreement and discrepancies were examined using the percentage of agreement, weighted kappa statistics, Pearson correlation coefficients, and paired-sample t-tests. Undesirable discrepancy types included adolescents reporting lower scores for paternal physical activity parenting practices or higher scores for paternal screen time parenting practices than fathers. Participants’ sociodemographic characteristics and weight status were compared by discrepancy type using between-group t-tests or Chi-square tests. Associations between discrepancy type and adolescents’ physical activity and screen time were examined using multivariate regression analyses. Results The study sample was low-income with a high prevalence of overweight and obesity. Adolescent and paternal reports of activity parenting practices had poor agreement (percentages of agreement: 22.2–34.3%, weighted kappa statistics:

Latino children have a disproportionately high prevalence of obesity. Parenting styles and food- and activity-related parenting practices influence children’s weight and weight-related behaviors. Fathers are underrepresented in existing healthy lifestyle intervention studies for families. The Padres Preparados, Jóvenes Saludables program was designed with an emphasis on paternal involvement for preventing childhood obesity among early adolescents. It offers eight weekly sessions delivered by Extension educators at community sites, with major topics of parenting skill training, positive parent-adolescent relationships, and healthy lifestyles related to healthy eating, physical activity, and screen time. The current study described pilot testing of the program for feasibility with a small sample of families in the Spring of 2017. Of the thirteen parents enrolled in the program, nine families, including all fathers, completed the program by attending five or more sessions and pre- and post-intervention evaluation sessions. Participant feedback indicated that program satisfaction was high. Participants also reported positive behavioral changes related to dietary intake, food- and activity-related parenting practices, and general parenting style. Findings demonstrated the feasibility of the program for engaging Latino fathers in promoting healthy lifestyle behaviors among early adolescents.

Introduction: Statins may have pleiotropic effects in COPD, but mechanisms remain unclear. Objectives: To assess the pleiotropic effect of statins in patients with stable COPD on (1): lung function (2); pulmonary and systemic inflammation (3); endothelial function (vascular stiffness) and circulating vascular growth factors; and (4), serum uric acid levels. Method: Pilot, double-blind, randomized, placebo-controlled clinical trial in 24 patients with stable COPD, all statin-naïve, who were randomized (1:1) to receive simvastatin 40 mg/24 h during 12 weeks (n = 12; 69.0 ± 7.3 years; post-bd FEV1 53.4 ± 10.0% pred.) or placebo (n = 12; 66.4 ± 4.6 years; post-bd FEV1 48.2 ± 12.6% pred.). Nine patients per group (total n = 18) completed the study. Results: Lung function, pulmonary and systemic inflammatory markers and the degree of vascular stiffness did not change significantly in any group. However, treatment with simvastatin increased the plasma levels of erythropoietin (Epo) (4.2 ± 2.2 mIU/mL to 6.8 ± 3.2 mlU/mL, p

Langerhans cell sarcoma of the skin is a rare tumor with aggressive behavior. There are reports of Langerhans cell sarcoma involving the skin in patients with underlying systemic Langerhans cell histiocytosis. However, to our knowledge, sarcomatous transformation of skin Langerhans cell histiocytosis, has not been previously described. We report a case of Langerhans cell sarcoma of the skin representing a probable transformation from Langerhans cell histiocytosis. The lesion had a clinical and pathological biphasic pattern, presenting as a plaque and nodule in the lower leg of a 66 year-old female. The plaque area showed a superficial epidermotropic proliferation of atypical Langerhans cells. The associated deep nodule had an overtly sarcomatous Langerhans cell proliferation. The immunohistochemistry profile was characteristic of Langerhans cells in both components. We consider this case a unique example of deep nodular Langerhans cell sarcoma of the skin, in which the associated superficial Langerhans cell proliferation is consistent with the precursor lesion.

Introducción. La inocuidad alimentaria ha sido reconocida mundialmente como una función esencial en salud pública. Una de las primeras causas de muerte en los países en desarrollo son las enfermedades transmitidas por alimentos, que afectan millones de personas en el mundo. El presente estudio fue realizado dentro del marco de un convenio interadministrativo planteado en Colombia para mejorar el estatus sanitario de la producción agroalimentaria del país. Objetivo. Evaluar la calidad higiénico-sanitaria del agua utilizada en una muestra aleatoria de productos de industrias colombianas de alimentos. Materiales y métodos. Se llevó a cabo un estudio descriptivo transversal. Incluyó 66 industrias localizadas en ocho departamentos y en el Distrito Capital. Se hicieron determinaciones analíticas de trece parámetros fisicoquímicos, tres parámetros microbiológicos, plaguicidas organofosforados y carbamatos, y diez tipos de metales. Resultados. La actividad económica de la mitad de las industrias provenía de la leche y sus derivados, y la otra mitad de productos cárnicos. Según las normas vigentes para el agua de consumo humano, el índice de riesgo de la calidad del agua fue alto en 4,5% de las industrias alimentarias, medio en 34,8%, bajo en 16,7%, y sin riesgo en 43,9%. Los parámetros con mayor número de muestras fuera de la norma fueron los microbiológicos (21,2%) y el cloro residual (28,8%). Conclusión. Aunque es un estudio preliminar, los resultados indican que el agua utilizada en la mayoría de las industrias participantes puede producir deterioro de los alimentos y ser una vía de transmisión de microorganismos patógenos; por lo tanto, es importante organizar un programa continuo de seguimiento y control.

Teams composed of electronic engineers and animal science scientists are nowadays [...]

Tumors of the matrix of rigid structures include matrical tumors of the hairs, nails, and teeth. These tumors share similar phenotypical and signaling features. Although benign matrical hair tumors are among the most common of these tumors, hair matrix tumors containing pigmented melanocytes are very rare. The malignant variant called melanocytic pilomatrix carcinoma contains benign colonizing dendritic melanocytes admixed with the carcinomatous follicular matrical cells. We studied the expression of cadherins and β-catenin in melanocytic pilomatrix carcinoma because cadherin/catenin-dependent cell-cell adhesion and signals play a critical role in the development of hair and hair tumors. We examined the expression of E- and P-cadherin and the multifunctional protein β-catenin in two cases of melanocytic pilomatrix carcinoma by immunohistochemistry. E- and P-cadherin are expressed at the cell membrane. In contrast, β-catenin is distributed uniformly in the nucleus and cytoplasm of all tumor cells. The diffuse nuclear and cytoplasmic β-catenin expression found in melanocytic pilomatrix carcinomas is indicative of transcriptional activation and β-catenin-induced cell transformation. This is the first report of cadherin/catenin expression in melanocytic pilomatrix carcinoma. Although the study is limited by the number of these rare tumors, the data add information for the understanding of disease mechanisms in hair matrical tumors. Matrical tumors of the hairs share phenotypical features with other matrical tumors and show nuclear translocation of β-catenin, suggesting a transcriptional activating rather than a cellcell adhesion function.

Registro de um caso da doença de Creutzfeldt-Jakob, forma de Heidenhain, que se caracteriza por comprometimento visual importante. As manifestações iniciais consistiram de distúrbios visuais. A paciente evoluiu para franca demência, ao lado de manifestações pirâmido-extrapiramidais. Além dos dados clínicos o EEG mostrou atividade periódica característica da doença. O estudo anátomo-patológico confirmou o diagnóstico clínico mostrando alteração esponjosa, degeneração neuronal e astrogliose. Além do quadro clínico, eletrencefalográfico e anátomo-patológico são discutidos os aspectos etiopatogênicos da doença.