409 resultados para elevator shaft


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Local mRNA translation in neurons has been mostly studied during axon guidance and synapse formation but not during initial neurite outgrowth. We performed a genome-wide screen for neurite-enriched mRNAs and identified an mRNA that encodes mitogen-activated protein kinase kinase 7 (MKK7), a MAP kinase kinase (MAPKK) for Jun kinase (JNK). We show that MKK7 mRNA localizes to the growth cone where it has the potential to be translated. MKK7 is then specifically phosphorylated in the neurite shaft, where it is part of a MAP kinase signaling module consisting of dual leucine zipper kinase (DLK), MKK7, and JNK1. This triggers Map1b phosphorylation to regulate microtubule bundling leading to neurite elongation. We propose a model in which MKK7 mRNA localization and translation in the growth cone allows for a mechanism to position JNK signaling in the neurite shaft and to specifically link it to regulation of microtubule bundling. At the same time, this uncouples activated JNK from its functions relevant to nuclear translocation and transcriptional activation.

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A study to assess possible exposure to carcinogenic metabolites (aflatoxins) from a mold Aspergillus flavus has been made in a rice producing area of Brazoria County, Texas. One hundred samples of unmilled rice were analyzed by thin-layer chromatography (TLC) for the amount of aflatoxin produced by the mold during rice growth and storage. Two well water samples and two rice elevator dust samples were also checked for possible aflatoxin content. The mortality rates from gastrointestinal and urinary tract cancers in the rice-growing part of the county were compared with mortality rates in the nonrice-producing areas of the same county.^ This study was an outgrowth of an earlier investigation by Cech and co-workers in Brazoria County which focused on environmental differences, specifically on the quality of drinking water in the former residences of decedents from primary liver cancer. It also compared subjects who died from other causes. The author of this dissertation participated in this phase of the overall investigation by performing some of the chemical analyses and by preparing synographic maps of water quality, and thus, part of those results from the early phase is also included in this manuscript.^ No aflatoxin was detected by TLC methods. However, when extracts of rice dust were checked for mutagenesis by the Ames Salmonella-microsome assay as a supplement to the TLC analysis, the result suggested that these dusts might have contained mutagenic material. The age-adjusted mortality rates in the rice-growing area were higher than those in the comparison area for both male and female gastrointestinal tract cancer and for male urinary tract cancer, but the differences were not statistically significant. ^

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Point-of-decision signs to promote stair use have been found to be effective in various environments. However, these signs have been more consistently successful in public access settings that use escalators, such as shopping centers and transportation stations, compared to worksite settings, which are more likely to contain elevators that are not directly adjacent to the stairs. Therefore, this study tested the effectiveness of two point-of-decision sign prompts to increase stair use in a university worksite setting. Also, this study investigated the importance of the message content of the signs. One sign displayed a general health promotion message, while the other sign presented more specific information. Overall, this project examined whether the presence of the point-of-decision signs increases stair use. In addition, this research determined whether the general or specific sign promotes greater stair use. ^ Inconspicuous observers measured stair use both before the signs were present and while they were posted. The study setting was the University of Texas School of Nursing, and the target population was anyone who entered the building, including employees, students, and visitors. The study was conducted over six weeks and included two weeks of baseline measurement, two weeks with the general sign posted, and two weeks with the specific sign posted. Each sign was displayed on a stand in the decision point area near the stairs and the elevator. Logistic regression was used to analyze the data. ^ After adjustment for covariates, the odds of stair use were significantly greater during the intervention period than the baseline period. Furthermore, the specific sign period showed significantly greater odds of stair use than the general sign period. These results indicate that a point-of-decision sign intervention can be effective at promoting stair use in a university worksite setting and that a sign with a specific health information message may be more effective at promoting stair use than a sign with a general health promotion message. These findings can be considered when planning future worksite and university based stair promotion interventions.^

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A torque meter comprising hollow-keyed, input and output female shafts adapted to receive the male shafts of the power source and machine respectively. Each shaft has a circular flange whose face is perpendicular to the center line of the shafts. Each flange has a plurality of equally spaced cylindrical recesses machined into the inside face thereto adapted to receive conical inserts therein. Balls are contained by the conical inserts and transmit the rotational movement from the input to the output shaft. A stationary housing extends around the input and output shaft and has a transducer shell secured thereto. When force is applied to the input shaft to cause movement, the balls encounter torsional resistance which causes the balls to roll up the ramps of the conical seat inserts to separate the two torque flanges. The force transmitted through the balls causes rotation to the output shaft and produces tension to the stationary transducer shell. The stationary transducer shell is instrumented with semi-conductor strain gauges.

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Este plan se propone indagar cómo se construyen las concepciones del cuerpo en la práctica de la danza escénica occidental, a partir del análisis de fuentes bibliográficas escritas por maestros coreógrafos y bailarines del siglo XX. En este sentido, la danza opera como instancia de recorte específico sobre un tema más general; el de construir un aporte a los desarrollos de una teoría social del cuerpo, de reciente formación en nuestro país, en base al análisis de unos referentes empíricos concretos. Se espera poder construir líneas de análisis fructíferas que, en base a la deconstrucción del saber generado en el campo de las prácticas específicas a observar y su re-construcción con eje en los elementos de la teoría social contemporánea, articulen el problema y análisis del cuerpo, con tópicos básicos del análisis sociológico: la cuestión de la subjetividad, las nuevas formas de auto-dominio y auto-control y la cuestión de las prácticas o experiencias autónomas y disruptivas.

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Parte del conocimiento y la comprensión que poseemos de las sociedades del mundo antiguo procede del análisis de los textos literarios. El eje estructurador es el derrumbe de los valores y las instituciones que organizaron la vida quienes habitaron el Antiguo Egipto en el paso del Reino Antiguo al Reino Medio. Analizaremos la Profecía de Neferty ylas Admoniciones de Ipuwer. Habrían sido elaborados durante el Reino Medio y poseerían connotaciones propagandísticas de legitimación y justificación de la toma del poder por parte de Amenemhat I y sus sucesores. Elaborados dentro de los círculos palatinos, poseen una marcada intencionalidad política

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Parte del conocimiento y la comprensión que poseemos de las sociedades del mundo antiguo procede del análisis de los textos literarios. El eje estructurador es el derrumbe de los valores y las instituciones que organizaron la vida quienes habitaron el Antiguo Egipto en el paso del Reino Antiguo al Reino Medio. Analizaremos la Profecía de Neferty ylas Admoniciones de Ipuwer. Habrían sido elaborados durante el Reino Medio y poseerían connotaciones propagandísticas de legitimación y justificación de la toma del poder por parte de Amenemhat I y sus sucesores. Elaborados dentro de los círculos palatinos, poseen una marcada intencionalidad política

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Este plan se propone indagar cómo se construyen las concepciones del cuerpo en la práctica de la danza escénica occidental, a partir del análisis de fuentes bibliográficas escritas por maestros coreógrafos y bailarines del siglo XX. En este sentido, la danza opera como instancia de recorte específico sobre un tema más general; el de construir un aporte a los desarrollos de una teoría social del cuerpo, de reciente formación en nuestro país, en base al análisis de unos referentes empíricos concretos. Se espera poder construir líneas de análisis fructíferas que, en base a la deconstrucción del saber generado en el campo de las prácticas específicas a observar y su re-construcción con eje en los elementos de la teoría social contemporánea, articulen el problema y análisis del cuerpo, con tópicos básicos del análisis sociológico: la cuestión de la subjetividad, las nuevas formas de auto-dominio y auto-control y la cuestión de las prácticas o experiencias autónomas y disruptivas.

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Este plan se propone indagar cómo se construyen las concepciones del cuerpo en la práctica de la danza escénica occidental, a partir del análisis de fuentes bibliográficas escritas por maestros coreógrafos y bailarines del siglo XX. En este sentido, la danza opera como instancia de recorte específico sobre un tema más general; el de construir un aporte a los desarrollos de una teoría social del cuerpo, de reciente formación en nuestro país, en base al análisis de unos referentes empíricos concretos. Se espera poder construir líneas de análisis fructíferas que, en base a la deconstrucción del saber generado en el campo de las prácticas específicas a observar y su re-construcción con eje en los elementos de la teoría social contemporánea, articulen el problema y análisis del cuerpo, con tópicos básicos del análisis sociológico: la cuestión de la subjetividad, las nuevas formas de auto-dominio y auto-control y la cuestión de las prácticas o experiencias autónomas y disruptivas.

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Parte del conocimiento y la comprensión que poseemos de las sociedades del mundo antiguo procede del análisis de los textos literarios. El eje estructurador es el derrumbe de los valores y las instituciones que organizaron la vida quienes habitaron el Antiguo Egipto en el paso del Reino Antiguo al Reino Medio. Analizaremos la Profecía de Neferty ylas Admoniciones de Ipuwer. Habrían sido elaborados durante el Reino Medio y poseerían connotaciones propagandísticas de legitimación y justificación de la toma del poder por parte de Amenemhat I y sus sucesores. Elaborados dentro de los círculos palatinos, poseen una marcada intencionalidad política

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Escalator and moving walkway are multibody systems with a design of more than a century. Developed methodology allows studying and improving any subsystem of both systems. In addition, new concepts can be developed and tested without the necessity and cost of a real construction. CITEF (Railway Technologies Research Centre) has been modelling escalators for more than four years. Several complex and innovative models has been developed to characterize static, kinematic and dynamic escalator behaviour. The high number of mechanical elements that are part of escalators complicate modelling task. In this way, methodologies and tools have been developed in order to automate these task and saving computational and time costs. Developed methodologies have been validated with the results of comparing real measurements and simulated outputs from a dynamic model.

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INTRODUCTION: The EVA (Endoscopic Video Analysis) tracking system a new tracking system for extracting motions of laparoscopic instruments based on non-obtrusive video tracking was developed. The feasibility of using EVA in laparoscopic settings has been tested in a box trainer setup. METHODS: EVA makes use of an algorithm that employs information of the laparoscopic instrument's shaft edges in the image, the instrument's insertion point, and the camera's optical centre to track the 3D position of the instrument tip. A validation study of EVA comprised a comparison of the measurements achieved with EVA and the TrEndo tracking system. To this end, 42 participants (16 novices, 22 residents, and 4 experts) were asked to perform a peg transfer task in a box trainer. Ten motion-based metrics were used to assess their performance. RESULTS: Construct validation of the EVA has been obtained for seven motion-based metrics. Concurrent validation revealed that there is a strong correlation between the results obtained by EVA and the TrEndo for metrics such as path length (p=0,97), average speed (p=0,94) or economy of volume (p=0,85), proving the viability of EVA. CONCLUSIONS: EVA has been successfully used in the training setup showing potential of endoscopic video analysis to assess laparoscopic psychomotor skills. The results encourage further implementation of video tracking in training setups and in image guided surgery.

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The numerical analysis of certain safety related problems presents serious difficulties, since the large number of components present leads to huge finite elementmodels that can only be solved by using large and expensive computers or by making rough approaches to the problem. Tangling, or clashing, in the turbine of a jet engine airplane is an example of such problems. This is caused by the crash and friction between rotor and stator blades in the turbine after an eventual shaft failure. When facing the study of an event through numerical modelling, the accurate simulation of this problem would require the engineer to model all the rotor and stator blades existing in the turbine stage, using a small element size in all pieces. Given that the number of stator and rotor blades is usually around 200, such simulations would require millions of elements. This work presents a new numerical methodology, specifically developed for the accurate modelling of the tangling problem that, depending on the turbine configuration, is able to reduce the number of nodes up to an order of magnitude without losing accuracy. The methodology, which benefits from the cyclic configuration of turbines, is successfully applied to the numerical analysis of a hypothetical tangling event in a turbine, providing valuable data such as the rotating velocity decrease of the turbine, the braking torque and the damage suffered by the blades. The methodology is somewhat general and can be applied to any problem in which damage caused by the interaction between a rotating and static piece is to be analysed.

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Se realizará un análisis en baja frecuencia del comportamiento de sistemas vibratorios excitados principalmente por un motor eléctrico. El sistema está formado por un motor eléctrico acoplado a un volante de inercia que produce una carga sobre citado motor diferente según las configuraciones adoptadas, todo ello montado sobre una base metálica de acero, soportada esta, mediante resortes de diferente características. El estudio contemplará la identificación de frecuencias de excitación, resonancias, pérdidas de inserción de los sistemas, transmisibilidad, problemas de alineamiento, desajustes, modos propios... para cada una de las diferentes situaciones en las que opera el sistema. ABSTRACT. In this Project will proceed to an behavior analysis of vibrating systems in low frequency mainly excited by an electric motor. The system is comprised of an electric motor coupled to inertial flywheel (o flywheel) which produces a different load upon said engine according to the configurations adopted. This system is mounted on a steel metal base which is supported by springs of different characteristics. This study will consider the excitation frequency identification, system resonances, insertion loss, transmissibility, shaft dealignment, eccentricities, mismatches, modal frequencies of the plate… for each of the situations in which the system operates.