895 resultados para Guindaste lateral


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Settlement is a critical process in the life history of crabs, and thus affecting the abundance, distribution and structure of estuarine communities. The spatial pattern of settlement of megalopae of the shore crab Carcinus maenas along a longitudinal estuarine gradient (Mira River Estuary, Portugal) was examined, as well as its effects on the juvenile population. To measure megalopal settlement, four replicate collectors were deployed in six equally spaced stations along the estuarine axis. Juveniles were collected on the same locations with a quadrat randomly deployed on the substrate. To assess fine-scale megalopal settlement within a curved region of the estuary, replicate collectors were deployed on both margins along Moinho da Asneira curve. Megalopae settled differently along the six longitudinal points, with a tendency to attenuate their settlement upstream. Within the curved region, megalopae preferentially settled on the left margin collectors, probably due to the weaker velocity speeds felt on this margin. Concerning the overall juvenile density, there were significant differences among the stations distributed along the estuary, but they did no reflect a longitudinal dispersion attenuation pattern. Size-frequency distribution of the juvenile population showed that the average size is higher on the left margin. Recruits (carapace length between 1.0 mm and 3.4 mm) were more abundant on the upstream stations. Density of early juveniles (3.4 mm-6.5 mm) and juveniles (6.5 mm-10 mm) was more stable throughout the estuary axis than that of recruits. This distribution pattern may result from tidal excursion processes or mechanisms to avoid biotic interactions, such as predation and competition. (c) 2006 Elsevier Ltd. All rights reserved.

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La esclerosis lateral amiotrófica (ELA) es una enfermedad neurodegenerativa con una incidencia de 1-2 casos por 100.000 habitantes/año y una prevalencia de 4-6 casos por 100.000 habitantes (3,5 casos por 100.000 habitantes en España). La mayoría de los casos de ELA son esporádicos, pero el 5-10 % son familiares con herencia autosómica dominante. La edad media de aparición para ELA esporádica es de alrededor de los 60 años. El objetivo del presente estudio de casos ha sido analizar la importancia del papel del médico de atención primaria en la sospecha diagnóstica, derivación, seguimiento y acompañamiento del paciente con ELA y su familia. Para ello se han analizado dos casos clínicos de los tipos más característicos de ELA y las actuaciones de los médicos de atención primaria que los han atendido, reflejando que una mayor difusión de los síntomas y signos de ELA podrían contribuir a un diagnóstico más precoz y con mayor grado de certeza.

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Aim: Amyotrophic lateral sclerosis (ALS) is a chronic, neurodegenerative disease, which leads to development of malnutrition. The main purpose of this research was to analyze the impact of malnutrition on the course of the disease and long-term survival. Material and methods: A retrospective analysis has been performed on 48 patients (22 F [45,83%] and 26 M [54,17%], the average age of patients: 66,2 [43-83]) in 2008-2014.The analysis of the initial state of nutrition was measured by body mass index (BMI), nutritional status according to NRS 2002, SGA and concentration of albumin in blood serum. Patients were divided into two groups, depending on the state of nutrition: well-nourished and malnourished. The groups were created separately for each of these, which allowed an additional comparative analysis of techniques used for the assessment of nutritional status. Results: Proper state of nutrition was interrelated with longer survival (SGA: 456 vs. 679 days, NRS: 312 vs. 659 vs. 835 days, BMI: respectively, 411, 541, 631 days, results were statistically significant for NRS and BMI). Concentration of albumin was not a prognostic factor, but longer survival was observed when level of albumin was increased during nutritional therapy. Conclusions: The initial nutrition state and positive response to enteral feeding is associated with better survival among patients with ALS. For this reason, nutritional therapy should be introduced as soon as possible.

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BACKGROUND: This project addressed an unresolved issue involving measurement methods for determining step uniformity. Leading experts on stairway safety agree that lack of step uniformity within a flight contributes to risk of missteps. A relatively new method for precisely measuring step dimensions is the nosing-to-nosing method. An issue in applying the method is lack of agreement on the lateral location to make the measurements. That location depends on where stairway users ascend and descend relative to the width of the steps. A prior investigator examined people descending to determine the lateral distance between the handrail center and the mid-line of the person’s body. He found the median was 44 cm. AIM: The two objectives of the experiment were to: (1) determine if a different set of stairway users will have the same median lateral distance from the handrail as those described in the prior observational study, and (2) determine if the lateral distance of participants is affected by their direction of travel and use of a handrail. METHODS: The investigators established visible distance markers on one stairway in a campus building and videotaped volunteer students ascending and descending the flight of stairs. Each of the 16 participant ascended with and without using the handrail, and each descended with and without using the handrail. Images were printed and analyzed to determine their lateral distance between the inner edge of the handrail and a point midway between the participant’s knees. Results were analyzed statistically to test hypotheses corresponding to the two objectives. RESULTS: The previous study found a median lateral distance of 44 cm when measured from the center of the handrail. Using comparable data, the median found in this study was 25 cm. Results of this study indicated that lateral distance from the handrail is significantly affected by the direction of travel and by use of the handrail. The greatest lateral distance was for ascending with the handrail. The shortest lateral distance was for descending without the handrail. VALUE: Committees develop and periodically revise standards for stairways leading to fire exits and workplace facilities. The practical value of this project is providing empirical evidence that standard developing committees may consider when convening to update their requirements and guidelines on how to measure step uniformity.

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This paper presents a detailed description of the influence of critical parameters that govern the vulnerability of columns under lateral impact loads. Numerical simulations are conducted by using the Finite Element program LS-DYNA, incorporating steel reinforcement, material models and strain rate effects. A simplified method based on impact pulse generated from full scale impact tests is used for impact reconstruction and effects of the various pulse loading parameters are investigated under low to medium velocity impacts. A constitutive material model which can simulate failures under tri-axial state of stresses is used for concrete. Confinement effects are also introduced to the numerical simulation and columns of Grade 30 to 50 concrete under pure axial loading are analysed in detail. This research confirmed that the vulnerability of the axially loaded columns can be mitigated by reducing the slenderness ratio and concrete grade, and by choosing the design option with a minimal amount of longitudinal steel. Additionally, it is evident that approximately a 50% increase in impact capacity can be gained for columns in medium rise buildings by enhancing the confinement effects alone. Results also indicated that the ductility as well as the mode of failure under impact can be changed with the volumetric ratio of lateral steel. Moreover, to increase the impact capacity of the vulnerable columns, a higher confining stress is required. The general provisions of current design codes do not sufficiently cover this aspect and hence this research will provide additional guidelines to overcome the inadequacies of code provisions.