Historia biogeográfica de los mamíferos terrestres sudamericanos: problemas y enseñanzas

La historia de los marniferos sudamericanos, una verdadera experiencianatural a gran escala; importancia de la geografia como uno de los factores de laevolución. Los Cynodonta (gmpo cepa) en el bloque african@sudamericano; su  radiación y sus ensayos hacia el modelo mamifero. Origen y primeras dicotomias  de los mamiferos. Antigüedad del grupo en Sudamérica. Dicotomia  Marsupiales-Placentarios (segregación geográfica resultando de la apertura del Océano Índico y del Atlántico). Cuna, radiación y migraciones de los marsupiales. Placentarios del  antiguo fondo sudamericano y su historia (endemismo, convergencias, tipos   originales). Llegada de los monos ceboideos y de los roedores caviomorfos  (migración transatlántica; colonización por fundadores). Migraciones hacia las Antillas Mayores en el Neogeno. El Gran Intercambio con NorteaméricaExtinciones tardias. Aplicaciones en bioestratigrafia, paleoclimatologia y paleoecologia

Historia biogeográfica de los mamíferos terrestres sudamericanos: problemas y enseñanzas

La historia de los marniferos sudamericanos, una verdadera experiencianatural a gran escala; importancia de la geografia como uno de los factores de laevolución. Los Cynodonta (gmpo cepa) en el bloque african@sudamericano; su  radiación y sus ensayos hacia el modelo mamifero. Origen y primeras dicotomias  de los mamiferos. Antigüedad del grupo en Sudamérica. Dicotomia  Marsupiales-Placentarios (segregación geográfica resultando de la apertura del Océano Índico y del Atlántico). Cuna, radiación y migraciones de los marsupiales. Placentarios del  antiguo fondo sudamericano y su historia (endemismo, convergencias, tipos   originales). Llegada de los monos ceboideos y de los roedores caviomorfos  (migración transatlántica; colonización por fundadores). Migraciones hacia las Antillas Mayores en el Neogeno. El Gran Intercambio con NorteaméricaExtinciones tardias. Aplicaciones en bioestratigrafia, paleoclimatologia y paleoecologia

The Development and Use of a Mechanical Heart

This report deals with the problems involved in the development and use of a mechanical heart. An artificial lung is often used in conjunction with a mechanical heart so artificial oxygenation was also included. The material for this report was taken from medical journals, scientific journals, and textbooks of anatomy and physiology. Problems encountered in the development of a mechanical heart that were solved included the blotting of blood, hemolysis, air entering the blood, oxygenation of the blood, and the attachment of blood vessels to a mechanical heart. The clotting of blood was prevented by the use of heparin. Removal of the heparin effect was accomplished by transfusion of whole blood or, in some cases, protamine sulfate was successful. Hemolysis was reduced by making the functioning parts of the mechanical heart of smooth inert material. The pumping mechanisms of the later models move blood in a fashion similar to a living heart, thereby preventing trauma to the blood. Air was prevented from entering the blood by the use of a cellophane dialysis-tubing obturator and by removal of canulae while they were under a saline solution. The oxygenation of blood was accomplished through the use of dialysis, bubbling, or filming. Blood vessels were handled with care to prevent permanent injury. They were carefully selected for the return of the blood to the body. Short catheters were used whenever possible to prevent excessive pumping pressure. Catheters were pointed in the right direction to prevent excessive fluid accumulation in parts of the body. The mechanical heart is now a useful device and its use is increasing in many hospitals

Managing Pathogens of Greenhouse Geraniums with Biological Fungicides

Second Place, 2011 CFAES Undergraduate Research Forum, Environmental and Plant Sciences DivisionThe amount of pesticides used annually by the agriculture industry is nearly a billion pounds, worth over US $31 billion. According to the USDA, biological fungicides are beneficial fungi and bacteria that attack and control plant pathogens. The advantages of biological fungicides are reduced risks to the applicator, reduced number of applications, a shortened re-entry interval, and a potential to control both soilborne and foliar pathogens. Botrytis cinerea causes blight, a very common and destructive disease of greenhouse crops that is estimated to cause the largest economic loss of all ornamental diseases. Cease is a biological fungicide with the active ingredient Bacillus subtilis Strain QST 713, a ubiquitous naturally occurring bacterium that controls many plant fungal pathogens. The common practice recommended by plant pathologists of using different modes of action was incorporated into an experiment for controlling B. cinerea with a biological fungicide. Veranda O has the active ingredient of polyoxin D zinc salt, a byproduct of the soil bacterium Streptomyces cacaoi var. asoensis. The mode of action is to interfere with the fungal cell wall production by inhibiting chitin synthase. In this experiment, both biological fungicides were used alone and in alternating combinations, each starting with a different mode of action. Fungicides were sprayed once per week for four weeks inoculating with a spore suspension four hours later. Plants were bagged to maintain high humidity. Neither Cease nor Veranda O used alone gave significant disease control. However, using alternating combinations of the two biological fungicides on a weekly basis significantly reduced the sporulation of B. cinerea. The Cease/Veranda O combination gave the highest level of disease control when compared to the other treatments. The combination starting with Cease and then Veranda O on a weekly basis provided a comparable level of control to a fungicide commonly used by the greenhouse industry to manage botrytis gray mold. This data set shows that rotations between different types of biological fungicides may be suitable alternatives to conventional fungicides. Pythium spp. cause root rot on a variety of crops and is a serious disease of greenhouse geraniums. Rootshield is a biological fungicide currently available with the active ingredient Trichoderma harzianum Rifai strain KRL-AG2. Trichoderma spp. are fungi that are naturally present in many soils and habitats. They are known to colonize plant roots readily and grow on the roots as they develop. In addition to colonizing roots, Trichoderma spp. have been known to attack and parasitize other fungi through many different mechanisms. There has been limited work with Rootshield as a biological fungicide and its ability to control pythium root rot of geraniums. Rootshield was tested to determine its effectiveness in controlling root rot caused by two different pythium species in a controlled environment. This data set shows that using Rootshield to control two different pythium species can work in certain instances and depends on the environment and the inoculum load.CFAES Honors Department Undergraduate Research GrantEcke RanchNo embarg

Degrowth within – Aligning circular economy and strong sustainability narratives

This perspective calls for building greater understanding of overlapping and conflicting considerations between the sustainability principles that inform current conceptions of circular economy and degrowth. We contend that scholars and practitioners need to be pragmatic and to recognize evident ideological differences, but simultaneously to acknowledge beneficial similarities and complements. The common aim of both frameworks – to change business-as-usual and to enable human society to operate within ecological planetary boundaries – will likely engender opportunities to formulate new solutions. Management of the inherent tensions, such as the scale and scope of rebound effects, will continue to pose challenges. However, with thoughtful dialogue, commitment to respectful discourse, and more refined articulation we are confident that progress will be made. By building on synergies and seeking holistic strategies, the academic community, along with its transdisciplinary partners, can advance strong global sustainability efforts

The tail of the Jurassic fish Leedsichthys problematicus (Osteichthyes: Actinopterygii) collected by Alfred Nicholson Leeds - an example of the importance of historical records in palaeontology

The specimen of the tail of <i>Leedsichthys problematicus</i>, now in The Natural History Museum, London, was one of the most spectacular fossil vertebrates from the Oxford Clay Formation of Peterborough, but as an isolated find it shares no bones in common with the holotype of the genus and species. However, a letter from Alfred Nicholson Leeds and related documents cast valuable new light on the excavation of the tail, indicating that it was discovered with cranial bones, gill-rakers, and two pectoral fins, thereby including elements that can potentially be compared with those of the holotype. The documents also clearly indicate that The Natural History Museum's specimen is not part of the same individual as any other numbered specimen of <i>Leedsichthys</i> as had been speculated on other occasions. The maximum size of the animal represented by The Natural History Museum's specimen was possibly around 9 metres, considerably less than previous estimates of up to 27.6 metres for <i>Leedsichthys</i>. Historical documentary evidence should therefore be rigorously checked both when studying historical specimens in science, and in preparing text for museum display labels

Calabaria and the phytogeny of erycine snakes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73563/1/j.1096-3642.1993.tb00290.x.pd

Relevancia de los espacios de participación como instancias comunitarias de reflexión en Colegio O'Higgins de la comuna de Melipilla

Tesis (Magíster en Terapia Ocupacional)La presente tesis aborda la relevancia de los espacios de participacion como instancias comunitaria de reflexion en Colegio O’higgins de la comuna de Melipilla, considerando el discurso que tienen los miembros de la comunidad sobre estos espacios y las formas de participación, presentando la Escuela para Padres (EPP) como una instancia de participación y discusion que puede dar respuesta y aproximar a los integrantes del colegio en torno a a las distintas necesidades de la comunidad educativa. Esta investigación propone estas instancias como formas saludables, empáticas y asertivas de llevar a cabo las problemáticas, necesidades y discusiones que manifiestan y presentan los diferentes actores implicados en la comunidad educativa conformada tanto por personal docente como no docente, padres y estudiantes que la conforman. Surge como pregunta de investigación la importancia de los espacios de participación y reflexión en torno a temas claves como lo son la educacion, la participacion, la diversidad y la implementacion de la EPP como ejes centrales a considerar. Por medio de entrevistas semi-estructuradas realizadas a grupos de docentes, padres y estudiantes fue posible concretar los resultados obtenidos del análisis del discurso presentado por los mismos en torno a temas fundamentales contemplados en esta investigacion. Fue posible determinar una clara manifestación por parte tanto de profesores, estudiantes y apoderados de la necesidad de crear espacios de participación dentro y fuera de la comunidad escolar con la intención de mejorar la comunicación y fomentar la participación de todos quienes son parte del colegio. Si bien en su gran mayoría los entrevistados exponen la necesidad de estos espacios, padres argumentan la falta de tiempo como principal factor limitante en su participación. Se expuso además un desacuerdo en torno a la formación de los niños en cuanto a componentes valóricos de la educación entregados tanto por el colegio como las familias, y los profesores básicamente se comprometen únicamente dentro del marco institucional establecido. Todas estas sugerencias que consideramos para efectos de esta investigación invitan a facilitar y guiar la discusión de necesidades y requerimientos en espacios de participación, proponiendo la Escuela para padres como una de estas instancias