54 research outputs found
Controlling phlebotomine sand flies to prevent canine Leishmania infantum infection: A case of knowing your enemy
Leishmaniosis caused by Leishmania infantum is a widespread zoonotic disease that can be transmitted to animals and humans by their vectors, blood-sucking phlebotomine sand flies. To prevent canine leishmaniosis across the whole Mediterranean region, vector control is essential. Because of phlebotomine breeding sites are diverse, environmental larval controls have limited practical value. Control methods of adults are being evaluated, such as selective baits based on sugar feeding of males and females or Attractive Toxic Sugar Baits (ATSB), and the indoor use of Long-Lasting-Insecticidal Nets (LLINs) treated with permethrin to prevent sand fly bites complementing the Indoor Residual Spraying (IRS) approach suggested by WHO. Although several strategies exist, the best control measure to prevent canine Leishmania infantum is to treat dogs using biocidal topical formulations based on legal insecticides (PTs18) or repellents (PTs19) (as collars, spot-ons and/or sprays) during the period when the vectors are active. This means we need to really know the biology and life cycle of the sand fly vector. According to available data, by mapping ambient temperatures we can already predict high risk areas where vector densities will be higher. In ongoing research, new candidates are emerging to fight against sand flies including natural plant extracts with low impacts on the environment and host animal. Other options in the future could be systemic insecticides to help reduce sand fly populations in high density areas. In parallel, health authorities and professionals involved in animal and public health (veterinarians, physicians, entomologists and epidemiologists) must work together in a One Health approach to minimize Leishmania infection. Veterinarians play a crucial role in liaising between key stake holders and dog owners to ensure the latter act responsibly in using repellents as a preventive measure against sand fly bites
A interculturalidade em Educação Patrimonial: desafios e contributos para o ensino de História
Chagas disease and systemic autoimmune diseases among Bolivian patients in Switzerland
Educación patrimonial y formación inicial docente: aportes desde el rescate y conservación del patrimonio escolar
Educación patrimonial y TIC en España: marco normativo, variables estructurantes y programas referentes
Los entornos Lego y Logo en Robotica Educativa
In some recent projects aimed at renewing the methodology for an integrated science, mathematics and computer teaching, where the introduction of educational robots in school may help to make learning more meaningful and motivating, some questions raise: what interest offers to introduce robotics in primary and secondary education? What is learned through the activities of Robotics? How to design experiences of "good learning" (constructivist) with robots?
This paper attempts to answer the above questions, showing some discussions which compare the educational potential of LEGO Mindstorms environment for building and programming a physical robots with respect to LOGO softwares, with their virtual robot (the "turtle "). This analysis is conducted using as reference the "anthropological theory of didactics.
Learning in archaeological sites with mobile devices = Aprendizaje con dispositivos móviles en yacimientos arqueológicos
La relevancia social del mobile learning es cada vez más evidente. Estos mecanismos, a través de TICs y dispositivos móviles, se aplican ya en programas educativos en yacimientos arqueológicos y museos, pero la pregunta es si estos programas son efectivos para el aprendizaje. Para investigar esta cuestión, hemos evaluado la implementación de un programa educativo con contenidos histórico- patrimoniales ofertado para estudiantes de secundaria. Noventa estudiantes participaron en este estudio respondiendo un cuestionario que abordaba cuestiones relacionadas con la asimilación de contenidos conceptuales, la atención y la eficacia del programa, así como aspectos relacionados con la satisfacción, utilidad percibida y dificultad de uso de la tecnología móvil. Los resultados son satisfactorios respecto a la asimilación de contenidos, y se aprecian mejores resultados con la combinación de metodologías receptivas y el uso de tecnología móvil. La satisfacción y la percepción de la utilidad confirman los buenos resultados de anteriores trabajos
Nueva estrategia de síntesis del 2-amino-1-ciclopentencarbodi tioato de propilo y de los proligandos derivados tipo [N2S2]2-.
The compound 2-amino-1-propyl-cyclopentencarbodithioate (L1) from the 2-amino-1 cyclopenten dithiocarboxylic acid and, using a Schiff base reaction, the tetradentate proligands N,N’-alkyl- bis(2-amino-1-propyl-cyclopentencarbodithioate) (L2= ethyl, L3= propyl y L4= butyl) were prepared between L1 and the appropriate diamines. The proligands were characterized by MS and spectroscopic methods (UV-Vis, FTIR and NMR). The first evidence for several metal complexes with the ligands are reported
Hydrocarbon synthesis using Iron and Ruthenium/SiO2 with FISCHER-TROPSCH catalysis.
Fe2(CO)9, Fe3(CO)12 and Ru3(CO)12 clusters were used as precursors for silica supported metals. The impregnated silica solids were obtained in organic solvents under inert atmosphere and the adsorbed complexes and reduced metals characterized by FT-IR, SEM EDX and HRTEM. The catalysts showed good Fischer–Tropsch (FT) activity; the main products were alkanes, alkenes and medium and higher alcohols as analyzed by GCMS. The Ru catalysts showed higher alcohols selectivity. HRTEM showed Ru nanoparticle size
Synthesis of light alkenes on manganese promoted.
Synthesis of light alkenes on manganese promoted.
(González Cortés, Sergio Luis; Rodulfo Baechler, Serbia M. A.; Oliveros Bastidas, Alberto; Orozco, José; Fontal, Bernardo; Mora, Asiloé J.; Delgado, Gerzon)
Abstract
The light alkenes formation capacity and the interaction of Mn with Fe and Fe-Co
of Fischer-Tropsch catalysts have been studied. The samples were characterized
by X-ray diffraction and temperature-programmed reduction. It was found that Fe-
Co-Mn has a better catalytic stability than the Fe-Mn catalyst. It is proposed that
iron particle size and its interaction with oxide and carbide phases produced
during the catalytic reaction are mainly responsible for the high activity and light
alkene selectivity.
This article was jointly published by Akadémiai Kiadó, Budapest and Kluwer Academic Publishers, Dordrecht React.Kinet.Catal.Lett. Vol. 75, No. 1, 3-12 (2002)[email protected]@[email protected]@ula.veNivel monográfic
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