Comparison of methods for determining leaf area in tree rows

Accepted versio

A Bayesian Nonparametric Regression Model With Normalized Weights - A Study of Hippocampal Atrophy in Alzheimer’s Disease

Hippocampal volume is one of the best established biomarkers for Alzheimer’s disease. However, for appropriate use in clinical trials research, the evolution of hippocampal volume needs to be well understood. Recent theoretical models propose a sigmoidal pattern for its evolution. To support this theory, the use of Bayesian nonparametric regression mixture models seems particularly suitable due to the flexibility that models of this type can achieve and the unsatisfactory predictive properties of semiparametric methods. In this article, our aim is to develop an interpretable Bayesian nonparametric regression model which allows inference with combinations of both continuous and discrete covariates, as required for a full analysis of the dataset. Simple arguments regarding the interpretation of Bayesian nonparametric regression mixtures lead naturally to regression weights based on normalized sums. Difficulty in working with the intractable normalizing constant is overcome thanks to recent advances in MCMC methods and the development of a novel auxiliary variable scheme. We apply the new model and MCMC method to study the dynamics of hippocampal volume, and our results provide statistical evidence in support of the theoretical hypothesis

Telemonitoring for patients with COVID-19: recommendations for design and implementation

Despite significant efforts, the COVID-19 pandemic has put enormous pressure on health care systems around the world, threatening the quality of patient care. Telemonitoring offers the opportunity to carefully monitor patients with a confirmed or suspected case of COVID-19 from home and allows for the timely identification of worsening symptoms. Additionally, it may decrease the number of hospital visits and admissions, thereby reducing the use of scarce resources, optimizing health care capacity, and minimizing the risk of viral transmission. In this paper, we present a COVID-19 telemonitoring care pathway developed at a tertiary care hospital in the Netherlands, which combined the monitoring of vital parameters with video consultations for adequate clinical assessment. Additionally, we report a series of medical, scientific, organizational, and ethical recommendations that may be used as a guide for the design and implementation of telemonitoring pathways for COVID-19 and other diseases worldwide.Cardiolog

Ação inseticida do extrato de Derris amazonica Killip para Cerotoma arcuatus Olivier (Coleoptera: Chrysomelidae

A abundância e o potencial inseticida de Derris amazonica e a necessidade de controle de Cerotoma arcuatus Olivier (Coleoptera: Chrysomelidae) na cultura do feijão-caupi (Vigna unguiculata L. Walp) estimularam a realização desta pesquisa, que objetivou avaliar a ação inseticida do extrato de D. amazonica a adultos de C. arcuatus em condições de laboratório. Os bioensaios testaram as vias de intoxicação por ingestão de folhas contaminadas, contato com superfície contaminada e aplicação tópica, com delineamento experimental inteiramente casualizado, com quatro repetições. Os valores de mortalidade e consumo foliar dos insetos foram submetidos à análise de regressão, sendo utilizada a análise de Probit para determinação das CL50, da DL50 e dos TL50. O extrato de D. amazonica, contendo 3,7% de rotenona, foi tóxico para adultos de C. arcuatus via ingestão de folhas contaminadas (CL50=15,14 µL do extrato.mL-1 de água), superfície contaminada (CL50=0,45 µL do extrato.cm-2) e aplicação tópica (DL50=1,44 µL do extrato.g-1 do inseto). Mortalidades de adultos de C. arcuatus superiores a 80% e os menores tempos letais médios foram obtidos na concentração de 5% (v v-1) do extrato em todos os bioensaios. O consumo foliar de adultos de C. arcuatus foi inversamente proporcional a concentração do extrato quando expostos por via de ingestão foliar ou aplicação tópica, sendo inclusive observada inibição da alimentação dos indivíduos. O extrato de D. amazonica é tóxico para C. arcuatus e inibe a alimentação dos insetos a partir da concentração de 1% (v v-1).The abundance and insecticidal potential of Derris amazonica in addition to need of controlling Cerotoma arcuatus for bean crop stimulated this research. The objective of this work was to evaluate insecticide action of the extract of D. amazonica to adults of C. arcuatus in laboratory conditions. The bioassays were carried out using three distend methodologies: leaf intake, contact in treated surface (filter paper) and topical application. A completed randomized experimental design was used with four replications. Mortality values and leaf consumption of the insects were subjected to regression analyses, being the Probit analyses used to determine of the i.e., LC50, LT50 and LD50. The extract of D. amazonica containing 3.7% of rotenone was toxic to adults C. arcuatus when exposed to treated leaves (LC50 = 15.14 µl.mL-1), treated surface (LC50 = 0.45 µl.cm-2) and subjected to topical exposure (LD50 = 1.44 µl.g-1). In all bioassays the adults mortality was higher than 80% with lower median lethal times obtained with 5% (v.v-1) concentrations of the extract. Leaf consumption by adults C. arcuatus was inversely proportional to the concentration of the extract when exposed by leaf intake or topical application, also being observed inhibition of feeding individuals. The extract of D. amazonica is toxic to C. arcuatus and inhibits the feeding of insects from the concentration of 1% (v v-1)

Percepción de la población con respecto a medicamentos genéricos frente a los de marca en hospitales del Perú

El objetivo del estudio fue conocer la percepción de la población con respecto a medicamentos genéricos, frente a los medicamentos de marca, en hospita- les del Perú. Participaron del estudio 4.914 personas mayores de 18 años, de 13 ciudades del Perú; clasificándolas en Lima, grandes y pequeñas ciudades. Se exploraron características socioeconómicas, demográficas y de percepción de medicamentos genéricos, en comparación con los medicamentos de marca. Determinando las asociaciones para cada cruce de variables, se calcularon razones de prevalencias (RP) y sus intervalos del 95% de confianza (IC95%), usando regresiones de Poisson crudas y ajustadas con varianza robusta con Stata 14.0. De los 4.914 participantes, el 46,7% estaban de acuerdo con que los medicamentos genéricos son menos eficaces que los medicamentos de marca, el 49,3% ha recomendado o recomendaría a otras personas el uso de medica- mentos genéricos, además, el análisis multivariado encontró que las personas que tenían un ingreso económico menor a PEN 1.000 estaban predispuestas a recomendar un medicamento genérico (RP = 1,36; IC95%: 1,14-1,63). Los resultados ponen en manifiesto que la población peruana aún tiene conceptos equívocos y baja aceptación a los medicamentos genéricos. El presente estudio debería servir para desarrollar políticas de salud, que velen por el bajo costo y calidad a la hora de escoger un medicamento

Nivel de satisfacción de ciencias básicas en estudiantes de medicina de siete universidades del Perú

En la especialidad profesional de Medicina Humana, una formación educativa de pregrado de alta calidad es fundamental para garantizar un buen desarrollo profesional para los futuros médicos. Durante el mes de julio de 2015, se realizó un estudio descriptivo transversal multicéntrico, basado en la conducción de la encuesta a estudiantes de medicina de siete escuelas de medicina peruanas. De los 1228 participantes, el 50,1% (615) eran mujeres, la edad media fue de 20 años (rango intercuartil: 18-22 años). El 50.7% (623) estudió en una universidad privada, y el 37.5% (461) informó haber suspendido al menos un curso durante el curso principal; todos los aspectos evaluados tuvieron una puntuación entre 6 y 8 (en una escala de diez puntuaciones). Además, todos los intercuartiles oscilaron entre 5 y 9 puntuaciones. La satisfacción de los estudiantes de medicina evaluados es buena con respecto a la enseñanza de los cursos de ciencias básicas

Zoeal morphology of Pachygrapsus transversus (Gibbes) (Decapoda, Grapsidae) reared in the laboratory

Ovigerous females of Pachygrapsus transversus (Gibbes, 1850) were collected on the Praia Dura and Saco da Ribeira beaches, Ubatuba, São Paulo, Brazil. Larvae were individually reared in a climatic room at 25ºC temperature, salinities of 28, 32 and 35‰ and under natural photoperiod conditions. The best rearing results were observed at 35%o salinity. Seven zoeal instars were observed, drawing and described in detail. The data are compared with those obtained for P. gracilis (Saussure, 1858)