Avaliação do sistema radicular e de rizomas de um campo natural diferido em Bagé, RS.

A utilização do Campo Sulino natural na pecuária de forma cada vez mais intensa e constante tem provocado a diminuição da sua condição produtiva. A excessiva remoção da parte aérea afeta o desenvolvimento das raízes. Um sistema radicular bem desenvolvido permite às plantas forrageiras explorar maior volume de solo, melhorando a absorção de água e nutrientes. As raízes também funcionam como órgão de reserva, assegurando rápida rebrota e produtividade das plantas forrageiras. O diferimento é uma prática de manejo de pastagens que pode ajudar a recuperar o campo por meio de descanso programado durante um tempo determinado. Este trabalho avaliou o efeito do tratamento de diferimento sobre o sistema radicular de campo natural após três anos de aplicação (agosto de 2000 a julho de 2003) na Embrapa Pecuária Sul (Bagé, RS). As avaliações foram realizadas no campo com presença animal durante todo o ano e sob diferimento de verão/outono (sem animais na área de março a junho). Foram coletadas 18 amostras de solo em cada tratamento, nas profundidades de 0?10 cm e 10?20 cm. As raízes e os rizomas foram separados do solo e entre si, secos e pesados. Houve diferença (p<0,05) para a porcentagem de raízes e a massa da matéria seca de rizomas. A testemunha apresentou 83,98% das raízes na camada de 0?10 cm e o diferimento, 77,5%. Na camada de 10?20 cm, sob diferimento houve aumento de 35% de raízes em relação à testemunha. A maior massa de matéria seca de rizomas foi obtida em pastagem sob diferimento, com 106% a mais em comparação à testemunha. Os resultados indicam vantagem do descanso da pastagem dos Campos Sulinos, tanto no acúmulo de reservas (maior quantidade de rizomas) voltado à propagação de gramíneas rizomatosas de interesse, quanto também no desenvolvimento de raízes na camada de 10?20 cm.bitstream/item/31700/1/BPD-10.pd

Turbulent flows of generalized Newtonian fluids: mechanics and structural coherence

Most flows are turbulent in nature, yet fluids exhibit a plethora of inherent responses to applied stress. Fluids that respond in a linear manner, such as water and air, are labelled as Newtonian, whereas the majority of them that do not are often called non-Newtonian. Some of these fluids show instantaneous deformation in directions perpendicular to the applied stress, others present elastic recovery, or yield-stress (plasticity), and some even flow more easily under increasing shear stress. The latter, a type of shear-dependent rheology known as shear-thinning or pseudoplastic behaviour, is one of the most common non-Newtonian fluid behaviours in numerous industrial settings. Consequently, the understanding of turbulent flows of these fluids; i.e., those exhibiting sheardependent rheology, is fairly important for a good number of engineers and scientists. The present thesis is concerned with the investigation of turbulent flows corresponding to generalized Newtonian (GN) fluids. The aim is to study the mean-flow properties, and the features of some coherent structures; more specifically, turbulent vortices. For this purpose, the numerical simulations of two distinct flows are considered: turbulent channel flow, and turbulent flow in a baffled stirred tank with a Rushton-type impeller. Here, a GN fluid refers to an idealization of a real fluid presenting shear-dependent rheology as its most characteristic rheological feature. GN fluids are modelled through a so-called constitutive equation, where the response to stress is made proportional to it through a material function (apparent shear viscosity) depending on the rate of deformation. In this work, the Carreau model is selected to incorporate the GN fluid rheology into the momentum equation. Key accomplishments of this thesis include: (i) the displaying of drag reducing features in turbulent channel flow for a slight-to-moderate degree of shear-thinning, even in the absence of other non-Newtonian behaviours (e.g., extensional thickening, or elastic effects); (ii) the discovery of qualitative similarities between turbulent pipes and turbulent channels of GN fluids, which hints to the possibility of having a universal near-wall behaviour for these internal flows even after complex effects are introduced; (iii) the analysis of quasi streamwise vortices, and of the near-wall self-sustaining process in turbulent channel flow of a shear-thinning fluid; (iv) the presentation of the mean momentum balance analysis (see, e.g., Klewicki, 2013) for turbulent channel flow of GN fluids; (v) the study of turbulent vortices in a baffled stirred tank with (potential) important implications for dispersed systems; among other findings

Propuesta para La reorganización del servicio de salud bucodental del Centro de Salud Magally E. Ruiz. 1996.

Este estudio se realizó en el Servicio de Salud Bucodental del Centro de Salud Magally Ruiz, situado en distrito de La Chorrera. Se trata de una investigación multietápica constituida por tres etapas cada una con propia población de estudio: los elementos de la estructura del servicio, los usuarios del servicio y los escolares con área de responsabilidad. Para cada población se elaboró y aplicó una encuesta. Los resultados obtenidos permitieron concluir que: el modelo actual de organización del servicio de salud bucodental se limita a responder con actividades específicas a la demanda que acude a solicitar atención curativa, la prevalencia de caries y enfermedad periodontal de la población estudiada es muy elevada, la cobertura, concentración e impacto del servicio son muy bajas, las actividades de promoción de la salud bucodental son escasas, su contenido es muy general y no motivan al paciente a modificar sus conductas relacionadas con la salud oral, existen cuellos de botella que hacen tediosa y demorada la atención en el servicio de salud bucodental. Por tales hallazgos se propone un modelo de alta productividad, con componente preventivo definido que conducirá. a: elevar las coberturas, concentración e impacto en la población, su responsabilidad, reducir las incomodidades a las que están expuestos los usuarios, fortalecer el trabajo en equipo, utilizar mejor los recursos disponibles, orientar la demandas hacia actividades preventivas y modificar los hábitos, higiene y alimentación de la población de responsabilidad

Effects of shear-thinning rheology on near-wall turbulent structures

Turbulent channel flow simulation of a shear-thinning fluid is considered - see Arosemena et al. (J. Fluid Mech., vol. 908, 2021, p. A43) - and compared with a Newtonian base case to reveal the effects of the shear-dependent rheology on the near-wall structures. Analyses of different flow statistics revealed that, for the shear-thinning fluid case, the streamwise vortices appear to grow in size, depart from the wall and present a lessening in their intensity. Information regarding variations in the quasi-longitudinal vortices is also obtained from three-dimensional structures identified through a normalized -criterion. With shear-thinning rheology, it is shown that the structures are comprised of wall-attached and -detached families which are taller than for a Newtonian fluid. Also, for a given height, the structures appear to be longer, with approximately the same width and overall larger volume for the shear-thinning fluid case; albeit their fractal dimension remains the same when compared to the Newtonian base case. Moreover, it is observed that the number density of vortical structures decreases with shear-thinning fluid behaviour. These observations, in conjunction with the known changes to the longitudinal velocity structures which appear to be less streaky, more spanwise separated and thickened with shear-thinning rheology, strongly suggest that the near-wall self-sustaining process has been disrupted. As we move slightly away from the wall and with shear-thinning behaviour, the local increase in viscosity seems to lead to less energetic vortices whereas the streaks are provided with an additional source of energy due to fluctuations in viscosity

Efecto de la actividad antropogénica en la zona de amortiguamiento del Parque Nacional Santa Fe, Panamá

Anthropogenic solid waste in the buffer zone of Santa Fe National Park will be determined and quantified. The methodology used will consist of classifying and quantifying the organic and inorganic waste present in the study area using a checklist. In addition, anthropogenic impacts present in the area that threaten the sustainability and purity of the park will be identified. Data will be collected twice a month from January to April 2024. The results will be analyzed with descriptive statistics. The large amount of anthropogenic solid waste will indicate whether the population disposes of its waste inappropriately and disturbs the segment that borders Santa Fe National Park in some way. Therefore, we intend to raise awareness among the population through environmental education strategies in Alto de Piedra and in the Santa Fe district, looking for an area with less anthropogenic impacts.Se determinará y cuantificará los desechos sólidos antropogénicos en la zona de amortiguamiento del Parque Nacional Santa Fe. La metodología utilizada consistirá en clasificar y cuantificar con una lista de cotejo los desechos orgánicos e inorgánicos presentes en el área de estudio. Además, se identificarán los impactos antropogénicos presentes en esa zona que ponen en riesgo la sostenibilidad y la pureza del parque. Los datos se recogerán dos veces al mes de enero a abril de 2024. Los resultados se analizarán con estadística descriptiva. La gran cantidad de desechos sólidos de origen antropogénico nos indicaran si la población hace una disposición inadecuada de sus desechos y perturba de alguna manera el segmento que colinda con el Parque Nacional Santa Fe. Por lo antes descrito se pretende concientizar a la población mediante estrategias de educación ambiental de manera puntal en Alto de Piedra y en el distrito de Santa Fe, buscando esa área con menos impactos antropogénicos

Integument Mycobiota of Wild European Hedgehogs (Erinaceus europaeus) from Catalonia, Spain

There are some reports about the risk of manipulating wild hedgehogs since they can be reservoirs of potential zoonotic agents like dermatophytes. The aim of this study was to describe the integument mycobiota, with special attention to dermatophytes of wild European hedgehogs. Samples from spines and fur were cultured separately in Sabouraud dextrose agar (SDA) with antibiotic and dermatophyte test medium (DTM) plates. Nineteen different fungal genera were isolated from 91 cultures of 102 hedgehogs. The most prevalent genera were Cladosporium (79.1%), Penicillium (74.7%), Alternaria (64.8%), and Rhizopus (63.7%). A lower prevalence of Aspergillus (P = 0,035; χ 2 = 8,633) and Arthrinium (P = 0,043; χ 2 = 8,173) was isolated during the spring time and higher frequencies of Fusarium (P = 0,015; χ 2 = 10,533) during the autumn. The prevalence of Acremonium was significantly higher in young animals (70%, 26/37) than in adults (30%, 11/37) (P = 0,019; χ 2 = 5,915). Moreover, the majority of the saprophytic species that grew at the SDA culture were also detected at the DTM. Finally, no cases of ringworm were diagnosed and no dermatophytes spp. were isolated. Concluding, this study provides the first description of fungal mycobiota of the integument of wild European hedgehogs in Spain, showing a large number of saprophytic species and the absence of dermatophytes

Cell-Free DNA Fragments as Biomarkers of Islet β-Cell Death in Obesity and Type 2 Diabetes

Type 2 diabetes (T2D) typically occurs in the setting of obesity and insulin resistance, where hyperglycemia is associated with decreased pancreatic β-cell mass and function. Loss of β-cell mass has variably been attributed to β-cell dedifferentiation and/or death. In recent years, it has been proposed that circulating epigenetically modified DNA fragments arising from β cells might be able to report on the potential occurrence of β-cell death in diabetes. Here, we review published literature of DNA-based β-cell death biomarkers that have been evaluated in human cohorts of islet transplantation, type 1 diabetes, and obesity and type 2 diabetes. In addition, we provide new data on the applicability of one of these biomarkers (cell free unmethylated INS DNA) in adult cohorts across a spectrum from obesity to T2D, in which no significant differences were observed, and compare these findings to those previously published in youth cohorts where differences were observed. Our analysis of the literature and our own data suggest that β-cell death may occur in subsets of individuals with obesity and T2D, however a more sensitive method or refined study designs are needed to provide better alignment of sampling with disease progression events