The Zerzura Terrarium : oases of migratory species

Abstract: Please refer to full text to view abstractM.Tech. (Architecture

Web System as support to the Management of Tutoring in the University Careers: Case Study: EPIS - UNH

The present investigation Web System as support to the Management of Tutorials in University Careers had as purpose to demonstrate the influence of the web system in the management of tutorials of the professional career of Systems Engineering of the National University of Huancavelica. It is an investigation of the applied type of descriptive level, as a procedure to contrast the hypotheses the test of comparison of means t-Student was used, for related samples, using the direct observation technique. As a result, the hypothesis can be verified with a significance of 0.5, giving a P-value = 0.00. Concluding that there is a difference between the indicators of the tutorial management variable before and after implementing the web system, proving that the use of a web system is beneficial in the management of tutorials in university careers.La presente investigación Sistema Web como apoyo a la gestión de tutorías en las carreras universitarias tuvo como finalidad demostrar la influencia del sistema web en la gestión de tutorías de la carrera profesional de Ingeniería de Sistemas de la Universidad Nacional de Huancavelica. Es una investigación del tipo aplicada de nivel descriptivo, como procedimiento para contrastar las hipótesis se utilizó la prueba comparación de medias t-Student, para muestras relacionadas, haciendo uso de la técnica de observación directa. Como resultado se puedo comprobar la hipótesis con una significancia de 0.5, dando un P-valor = 0.00. Concluyendo que existe una diferencia entre los indicadores de la variable gestión de tutorías antes y después de implementar el sistema web, comprobando que el uso de un sistema web resulta beneficioso en la gestión de tutorías en las carreras universitarias

The spatial pattern of natural selection when selection depends upon experience

Apostatic (frequency‐ or density‐dependent) selection, aposematic signals, and mate choice behavior generally require that the mean prey or potential mate density m value be high enough (above a threshold T) to result in sufficient encounter rates for the searcher to learn or retain the association between conspicuous signals and prey unprofitability, to forage apostatically, or to choose among mates. This assumes that all searchers experience , which implicitly assumes an even dispersion of targets among searcher territories. Uneven dispersion generates new phenomena. If , then only territories with local density x values that are greater than T favor experience‐based behavior, leading to spatially variable frequency‐ or density‐dependent selection intensity. As aggregation increases, the increase in percentage of targets in favorable territories ( ) is greater than the increase in the percentage of territories that are favorable. The relationship is reversed when . In both cases, because as few as 10% of the territories can contain 80% of the targets, only a few territory holders may account for most of the selection on most of the target population; accidents of experience in only a few searchers can have unexpectedly large effects on the target population. This also provides an explanation for high searcher behavior variation (personalities) : individuals from favorable territories will behave differently in behavioral experiments than those from unfavorable territories, at least with respect to similar kinds of targets. These effects will generate spatial heterogeneity in natural and sexual selection in what are otherwise uniform environments.<br /

Área en unidades triangulares

El presente trabajo está enmarcado en los pensamientos espacial y métrico propuestos por el MEN (2006). En él se presenta un taller relacionado con la construcción de una fórmula que permita hallar el área de figuras planas en unidades triangulares(utilizando como unidad de medida un triángulo equilátero de lado 1 centímetro). Este taller se estructuró gracias al trabajo realizado durante algunas de las sesiones de clase del espacio de formación Didáctica de la Geometría, asignatura de quinto semestre del proyecto curricular Licenciatura en Educación Básica con Énfasis en Matemáticas dirigido por el docente William Jiménez, REPITE EN PÁGINAS 2 Y 3 además de tener en cuenta algunos referentes teóricos para su consecución

Síntesis y caracterización de compuestos de coordinación con cromo (III) y ligantes imino- aminoester

Se reporta la síntesis de un compuesto iminoester (3) a partir de bencilamina (1) y acetoacetato de etilo (2) en metanol anhidro. El aminoester (4) fue obtenido a partir de la reducción del compuesto 3 con Borohidruro de sodio en metanol anhidro. Los compuestos 3 y 4 fueron caracterizados por espectroscopia IR y RMN1H y 13C. El imino-ester 3 fue analizado por GC-MS. El producto 4 en presencia del ion metálico Cromo (III) no estabiliza compuestos de coordinación en metanol y agua. La reducción del aminoester (4) a aminoalcohol con hidruro de litio y aluminio es sujeta a modificaciones en el medio de reacción

THE HEALTH BENEFITS OF NATURAL SKIN UVA PHOTOPROTECTIVE COMPOUNDS FOUND IN BOTANICAL SOURCES

In recent years, botanicals have gained importance due to their dermal photoprotective effect against the harmful UV radiation. This radiation generates reactive oxygen species which attack proteins, lipids, and nucleic acids among others. This leads to the cellular oxidation, which is reflected as tanning, skin inflammation, erythema, immunosuppression, photoaging and skin cancer. The photoprotective activity of synthetic sunscreens is unsatisfactory due the proved incomplete spectral protection, toxicity, and allergenicity. The phytotherapy treatment with antioxidant compounds with potential UV absorbing capacity could offer a more effective photoprotection since they may impede, reverse or delay the process of formation of DNA adducts. The wide diversity of botanicals with photoprotective activity is attributed to several types of substances with phenolic chromophores. These compounds can be classified as flavonoids, phytoestrogens, carotenoids, xhantophylls, coumarins, proanthocyanidins, anthocyanins, catechins, phenolic acids, triterpenes, alkaloids, etc. The bioactivity of these compounds is not limited to the photoprotective action, but antioxidant, anti-inflammatory, antimutagenic and immunomodulatory properties. The regular intake of these botanicals not only prevents but also delays the deleterious effects of sun radiation onto the skin. Therefore, these botanicals have gained considerable attention and are now included in most vitamin and cosmetic products. This review gives an overview of photoprotective botanicals mainly focused on UVA chromophores that are able to inhibit or reverse the damaging effects of sun radiation. The search criterion was made essentially on UVA photoprotective botanicals and related works published in the last ten years. The literature search included mainly the Google scholar, Science direct, and ISI web of knowledge databases.Keywords: Ultraviolet radiation, Photoprotective botanicals, Antioxidants, Phytotherapy

ASSESSMENT OF THE TABLETING CHARACTERISTICS OF A NOVEL SORBITOL AND CALCIUM DIPHOSPHATE COMPOSITES

Objective: To improve the tableting properties of sorbitol (SOR) via particle engineering through agglomeration with anhydrous calcium diphosphate (ACD) employing a house-made agglomerator.Methods: A novel SOR: ACD composites were produced by agglomeration at the 95:5; 80:20, 50:50, 20:80 and 6:94 SOR to ACD. The resulting tableting properties such as densification, compressibility, compactibility, ejection force, elastic recovery, sensitivity to lubricants, compression speed and disintegration time were then evaluated.Results: The new agglomerated excipient had better flow, compressibility and compactibility than the physical mixture of SOR and ACD being the 95:5 SOR: ACD ratio the composite that exhibited the best tableting properties.Conclusion: This novel excipient has a potential use as a pharmaceutical aid for direct compression applications.Â