Development of a Procedure for Determining Spacial and Time Variations of Precipitation in Venezuela

An analysis of the influence of the length of the record in the reliability of mean values of precipitation was made for the Caracus-Cagigal Station in Venezuela. Ten series of values were obtained for 10, 15, 20, 25, 30, and 35-year periods, extracted for sliding intervals for the overall record of 75 years. The reliability of mean values computer from Figure 3 was quite low for 10, 15, and 20- year periods. The long term record means had higher reliability, increasing with the number of years in the records, but the differences are not important in terms of accuracy. Precipitation values for .2, .10, .20, .30, .40, .50, .60, .70, .80 .90, and .95 equal or less probability levels were computed based on an incomplete gamma distribution for 126 stations distributed throughout Venezuela. Computer programs were used to process the data

Computerized Machine for Cutting Space Shuttle Thermal Tiles

A report presents the concept of a machine aboard the space shuttle that would cut oversized thermal-tile blanks to precise sizes and shapes needed to replace tiles that were damaged or lost during ascent to orbit. The machine would include a computer-controlled jigsaw enclosed in a clear acrylic shell that would prevent escape of cutting debris. A vacuum motor would collect the debris into a reservoir and would hold a tile blank securely in place. A database stored in the computer would contain the unique shape and dimensions of every tile. Once a broken or missing tile was identified, its identification number would be entered into the computer, wherein the cutting pattern associated with that number would be retrieved from the database. A tile blank would be locked into a crib in the machine, the shell would be closed (proximity sensors would prevent activation of the machine while the shell was open), and a "cut" command would be sent from the computer. A blade would be moved around the crib like a plotter, cutting the tile to the required size and shape. Once the tile was cut, an astronaut would take a space walk for installation

HIV Drug Resistance-Associated Mutations in Antiretroviral Naïve HIV-1-Infected Latin American Children

Our goal was to describe the presence of HIV drug resistance among HIV-1-infected, antiretroviral (ARV) naïve children and adolescents in Latin America and to examine resistance in these children in relation to drug exposure in the mother. Genotyping was performed on plasma samples obtained at baseline from HIV-1-infected participants in a prospective cohort study in Brazil, Argentina, and Mexico (NISDI Pediatric Study). Of 713 HIV-infected children enrolled, 69 were ARV naïve and eligible for the analysis. At enrollment, mean age was 7.3 years; 81.2% were infected with HIV perinatally. Drug resistance mutations (DRMs) were detected in 6 (8.7%; 95% confidence interval 3.1–18.2%) ARV-naïve subjects; none of the mothers of these 6 received ARVs during their pregnancies and none of the children received ARV prophylaxis. Reverse transcriptase mutations K70R and K70E were detected in 3 and 2 subjects, respectively; protease mutation I50 V was detected in 1 subject. Three of the 6 children with DRMs initiated ARV therapy during followup, with a good response in 2. The overall rate of primary drug resistance in this pediatric HIV-infected population was low, and no subjects had more than 1 DRM. Mutations associated with resistance to nucleoside reverse transcriptase inhibitors were the most prevalent

A Zugunruhe Data Collection System Using Passive Infrared Sensors

When engineers and biologists work together, there is a lot to learn on both sides. For instance, our work introduced us to zugunruhe, which is a German word that means “unrest”. It is used in the context of migratory birds, as they become restless at night, inside their cages, during their migratory period. When does zugunruhe start? It usually starts when the weather becomes cold and the days shorter, but it varies for different bird species. Moreover, global warming has caused changes in zungunruhe’s timing, which made it even harder to predict. Another question is about genetics: is there a specific gene or a group of genes that cause birds to migrate? To help scientists answer questions related to zugunruhe and the genes underlying migratory behavior, this paper presents the design and implementation of a zugunruhe data collection system to study the Swainson’s thrush, a migratory songbird that breeds in North America. Our goal is to share how custom-off-the-shelf (COTS) devices and existing technologies were used in this project, such as passive infrared motion sensors, telecom cables, custom printed circuit boards (PCB) and a data acquisition system using LabView software. All these were combined to monitor bird movements. We also discuss how the learned lessons from our first winter of data collection, in which we monitored 30 bird cages, led to improvements to scale the system to support the monitoring of 60 birds in the second year. Samples of the collected data are presented to show that the system works, which was validated by comparing our data with the images obtained using an infrared camera. Some of the challenges on maintaining the system are also discussed. Moreover, this paper provides an example of an interdisciplinary, applied research project that is still on-going, and it was created by a group of undergraduate students. We hope it can inspire other researchers and undergraduate students to get involved in interdisciplinary research

Energy communities in rural areas : The participatory case study of Vega de Valcarce, Spain

This study follows a multi-disciplinary approach to implementing an Energy Community (ECs) in Vega de Valcarce, a rural community in Spain. ECs are entities that encompass collective actions of citizens and other actors towards the open, democratic governance of renewable energy sources; ECs can take various technical and organisational forms. This study developed and evaluated socially accepted, technically optimal and feasible options for the implementation of the EC at Vega de Valcarce. We conducted a participatory multi-criteria analysis incorporating the results of mixed-integer linear programming for energy system optimisation and regulatory analysis of ECs under Spanish law. Our study showed that the main objectives of local stakeholders are the reduction of the energy bill and emissions. The limited liability company fulfilled legal and regulatory restrictions the best by implementing a bigger-sized EC. We summarise the key challenges of implementing an EC in a rural context, mainly legal and financial, and conclude with recommendations on how to overcome these. While contributing to understanding the roll-out of ECs in Spain and Europe, our research aims to provide a structured approach for the uptake of renewable energy in rural areas

Proceso de Diseño de un Instrumento para Evaluar la Gestión de la Investigación en la Universidad Panameña : Modelado del Benchmarking

The objective of this research was the construction of an instrument to evaluate the institutional management of research at the university. This instrument has been conceived on the basis of the theory of business benchmarking, using this theory in an innovative way in the academic environment of higher education. Benchmarking is a strategy with proven effectiveness, which compares processes to improve their quality, there are different types. The process itself of modeling and transformation from business to academic benchmarking is part of this research, developed in two stages: the first of construction of the instrument through the DELPHI technique and the judgment of expert teaching researchers and, a second, of validation. of the items that make up the aforementioned instrument through the Content Validation Coefficient (CVC) of Hernández and Nieto (2002), hereinafter CVC. The experts were also consulted to approve the use of two instruments designed by other authors, proposed to measure the two benchmark points in the Panamanian environment, that is, the aptitude and attitude of students towards research. It is concluded that the benchmarking instrument designed as a result of this research has the following qualities: it is academic given the transformation made in the business context from which benchmarking emerges towards higher education; respecting the principles of the theory that underpins it. The second characteristic is that it is external, comparative and collaborative, implying that the institutions that are compared will do so voluntarily and with the interest of mutual improvement. Finally, it is functional because it compares a specific function: research management at the university. It has a qualitative-quantitative, instrumental type approach; The population was made up of eight (8) research teachers; The technique for data collection was based on the DELPHI method; The information analysis method was based on basic statistics and the CVC of Hernández (2002) was used to validate each item. All of this resulted in an instrument composed of twenty-eight (28) items, grouped into three dimensions: structure (16), process (10) and results of research management at the university (2). All CVCs reached the minimum of 80 and others exceeded it (requirement to be accepted according to the author's scale).El objetivo de esta investigación fue la construcción de un instrumento para evaluar la gestión institucional de la investigación en la universidad.  Este instrumento ha sido concebido sobre la base de la teoría del benchmarking empresarial, utilizando esta teoría de forma innovadora en el ambiente académico de la educación superior. El benchmarking es una estrategia con efectividad Comprobada, que compara procesos para la mejora de su calidad, existen diferentes tipos. El proceso en sí de modelación y transformación del benchmarking empresarial al académico forma parte de esta investigación, desarrollada en dos etapas: la primera de construcción del instrumento por medio de la técnica DELPHI y el juicio de expertos docentes investigadores y, una segunda, de validación de los ítems que componen el mencionado instrumento a través del Coeficiente de Validación de Contenidos (CVC) de Hernández y Nieto (2002), en adelante CVC. Los expertos también fueron consultados para aprobar el uso de dos instrumentos diseñados por otros autores, propuestos para medir los dos puntos de benchmark en el entorno panameño, es decir, la aptitud y actitud de los estudiantes hacia la investigación. Se concluye que el instrumento de benchmarking diseñado producto de esta investigación posee las siguientes cualidades: es académico dada la transformación hecha del contexto empresarial de donde surge el benchmarking hacia la educación superior; respetando los principios de la teoría que lo fundamenta. La segunda característica es que es externo, comparativo y colaborativo, implicando que las instituciones que se comparan lo harán de forma voluntaria y con el interés de mejorarse mutuamente. Por último, es funcional porque compara una función en específico: la gestión de la investigación en la universidad. Tiene un enfoque cuali-cuantitativo, tipo instrumental; la población estuvo conformada por ocho (8) docentes investigadores; la técnica para la recolección de los datos estuvo basada en el método DELPHI; el método de análisis de la información se basó en la estadística básica y para la validación de cada items se utilizó el CVC de Hernández (2002). Todo esto dio como resultado un instrumento compuesto por veintiocho (28) ítems, agrupados en tres dimensiones: estructura (16), proceso (10) y resultados de la gestión de la investigación en la universidad (2). Todos los CVC alcanzaron el mínimo de 80 y otros lo superaron (requisito para ser aceptados según la escala del autor)

Immunolocalization and temporal distribution of cytokine expression during the development of vein graft intimal hyperplasia in an experimental model

AbstractPurpose: Vein graft stenosis caused by intimal hyperplasia (IH) accounts for 30% to 50% of late bypass graft failures; however, the biochemical mediators of vein graft IH have been poorly defined. We attempted to evaluate the spatial and temporal distribution of five principal cytokines (interleukin-1 beta [IL-1β], platelet-derived growth factor AA [PDGF-AA], basic fibroblast growth factor [bFGF], interferon gamma [INFγ], and tumor necrosis factor alpha [TNF-α]) during the development of IH in a rat vein graft model.Methods: Rat epigastric vein interposition grafts in the femoral artery were harvested at 6 hours, 2 days, 1 week, 2 weeks, and 4 weeks after the grafting procedure and studied with immunohistochemical and standard histologic techniques. The cytokine expression in the endothelium and media/neointima was quantified as the percentage of immunopositive cells per high-power field.Results: Maximal hyperplasia occurred 2 weeks after the grafting procedure. Peak expression of IL-1β and bFGF occurred by 2 days. PDGF-AA expression paralleled the development of IH, peaking at 2 weeks and then declining. TNF-α expression increased at 1 week and remained elevated. INFγ was seen only in control grafts.Conclusions: The coordinated early release of IL-1β and bFGF and the down-regulation of INFγ seem to trigger an inflammatory response, thereby initiating IH. The process then is propagated by the release of PDGF-AA and TNF-α, with concomitant smooth muscle cell proliferation and production of extracellular matrix. It is likely that this complex milieu of local paracrine signaling is required to generate the hyperplastic response seen in failing vein grafts. (J Vasc Surg 1996;24:463-71.