5,833 research outputs found
The earliest occurrence and remarkable stasis of the family Bostrichidae (Coleoptera: Polyphaga)in Cretaceous Charentes amber.
A new fossil species of auger beetle (Coleoptera: Bostrichidae), preserved in mid-Cretaceous (Albian-Cenomanian) amber from south-western France, is described as Stephanopachys vetus Peris, Delclòs et Perrichot sp. n. The species is the earliest fossil bostrichid discovered to date, but is remarkably similar to Recent species of the genus Stephanopachys, supporting long morphological conservation in wood boring beetles. The specimen is fossilized in fully opaque amber and was imaged in 3D using propagation phase-contrast X-ray synchrotron microtomography. Based on the ecology of extant related species habits, it is suggested that S. vetus sp. n. was a primary succession pioneer following wildfires in mid-Cretaceous forests. The fossil record of the family is reviewed
Red para la elaboración de materiales docentes en el análisis y tratamiento de datos geoquímicos y petrológicos
El trabajo realizado por esta red docente tiene por objetivo el desarrollo de materiales docentes específicos para el análisis y tratamiento de datos geoquímicos y petrológicos dentro de las asignaturas enmarcadas en el tercer curso del Grado en Geología: Petrología Ígnea y Metamórfica, Petrología Sedimentaria y Geoquímica y Prospección Geoquímica. El trabajo se ha centrado en la definición de las actividades a realizar por el estudiante, haciendo especial hincapié en la coordinación de los contenidos y distribución temporal entre las asignaturas anteriormente mencionadas. Los resultados obtenidos durante los cursos precedentes han mostrado la necesidad de desarrollar manuales, páginas webs y videos que permitan el autoaprendizaje del alumno. Una de las principales debilidades encontradas durante el tratamiento de datos radica en el conocimiento de los diferentes pasos intermedios que se realizan, las suposiciones que se consideran y los errores derivados de ellas. La gran parte del material y software docente existente solo proporciona el resultado final del tratamiento de los datos obtenidos en el estudio geoquímico y petrológico de las muestras naturales. Por lo tanto, el material desarrollado para solventar dichos problemas docentes incluye colecciones de problemas y prácticas, videos-tutoriales y el desarrollo de software propio o utilizando software libre
Lysosomal membrane stability in mussels
In 2012, the ICES Study Group on Integrated Monitoring of Chemicals and their Effects
provided a framework for integrated monitoring to the OSLO-Paris Commission.
UNEP/MAP and HELCOM expert groups have also developed guidelines on
integrated monitoring of chemicals and their effects for the Mediterranean and Baltic
Sea. This document provides the technical information for one of the biological effects
measurements, the lysosomal membrane stability (LMS), which is a part of the above
mentioned integrated monitoring approaches. Lysosomes are cytoplasmic, single
membrane organelles whose condition is sensitive to stress whether it be due to environmental
conditions or exposure to a wide array of contaminants. Two different
methodologies have been developed to assess LMS in mussels: an enzyme cytochemical
method using cryostatic sections of digestive gland tissue, and an in vivo cytochemical
method (using haemolymph cells). In this document, different aspects of
the operational procedures have been standardized and harmonized, with particular
reference to the in vivo cytochemical method. New graphical material has been added
to clarify criteria of interpretation and new external quality assurance programmes
for measurements of lysosomal membrane stability have been proposed. Background
(BAC) and environmental (EAC) assessment criteria to assess the LMS data are provided.
Additionally, a new scoring procedure to enhance the sensitivity of the LMS
measurements using the in vivo assay is provided.Versión del edito
A temperature sensitive live-attenuated canine influenza virus H3N8 vaccine
Canine influenza is a respiratory disease of dogs caused by canine influenza virus (CIV). CIV subtypes responsible for influenza in dogs include H3N8, which originated from the transfer of H3N8 equine influenza virus to dogs; and the H3N2 CIV, which is an avian-origin virus that adapted to infect dogs. Influenza infections are most effectively prevented through vaccination to reduce transmission and future infection. Currently, only inactivated influenza vaccines (IIVs) are available for the prevention of CIV in dogs. However, the efficacy of IIVs is suboptimal, and novel approaches are necessary for the prevention of disease caused by this canine respiratory pathogen. Using reverse genetics techniques, we have developed a live-attenuated CIV vaccine (LACIV) for the prevention of H3N8 CIV. The H3N8 LACIV replicates efficiently in canine cells at 33°C but is impaired at temperatures of 37 to 39°C and was attenuated compared to wild-type H3N8 CIV in vivo and ex vivo. The LACIV was able to induce protection against H3N8 CIV challenge with a single intranasal inoculation in mice. Immunogenicity and protection efficacy were better than that observed with a commercial CIV H3N8 IIV but provided limited cross-reactive immunity and heterologous protection against H3N2 CIV. These results demonstrate the feasibility of implementing a LAIV approach for the prevention and control of H3N8 CIV in dogs and suggest the need for a new LAIV for the control of H3N2 CIV.
Importance: Two influenza A virus subtypes has been reported in dogs in the last 16 years: the canine influenza viruses (CIV) H3N8 and H3N2 of equine and avian origins, respectively. To date, only inactivated influenza vaccines (IIVs) are available to prevent CIV infections. Here, we report the generation of a recombinant, temperature-sensitive H3N8 CIV as a live-attenuated influenza vaccine (LAIV), which was attenuated in mice and dog tracheal, explants compared to CIV H3N8 wild type. A single dose of H3N8 LACIV showed immunogenicity and protection against a homologous challenge that was better than that conferred with an H3N8 IIV, demonstrating the feasibility of implementing a LAIV approach for the improved control of H3N8 CIV infections in dogs
Linearizing Toda and SVD flows on large phase spaces of matrices with real spectrum
We consider different phase spaces for the Toda flows and the less familiar
SVD flows. For the Toda flow, we handle symmetric and non-symmetric matrices
with real simple eigenvalues, possibly with a given profile. Profiles encode,
for example, band matrices and Hessenberg matrices. For the SVD flow, we assume
simplicity of the singular values. In all cases, an open cover is constructed,
as are corresponding charts to Euclidean space. The charts linearize the flows,
converting it into a linear differential system with constant coefficients and
diagonal matrix. A variant construction transform the flows into uniform
straight line motion. Since limit points belong to the phase space, asymptotic
behavior becomes a local issue. The constructions rely only on basic facts of
linear algebra, making no use of symplectic geometry.Comment: 25 pages, 2 figure
Optical sensor to determine plant spacing for precise application
Congreso Agroingeniería 2015. Orihuela (Alicante). 1 a 3 de junio de 2015La automatización en el manejo de la mala hierba de forma individualizada está siendo una
realidad cada vez más cercana, tanto objetivos de eficiencia como de beneficio económico se
están consiguiendo. En un futuro muy próximo la mecanización y su diseño tendrá que
contemplar técnicas de monitorización o detección de precisión. El objetivo de este estudio fue
evaluar la capacidad de un sensor óptico para determinar el espacio entre las plantas de una
misma línea de cultivo en diferentes condiciones: laboratorio y campo. Este equipo de trabajo ha
investigado la detección del cultivo con un sensor fotoeléctrico de infrarrojo (880 nm) en modo
opuesto. La barrera fotoeléctrica de transmisión, usa un par de sensores y al paso de la planta
por la cortina de luz interrumpe el haz. La señal de luz se recibe de forma simultánea en tiempo
real mediante un sistema de control de alta velocidad. El sensor fotoeléctrico fue capaz de
detectar la planta de tomate y por tanto de terminar la separación entre ellas de forma muy
precisa. El uso de sistemas de detección como este puede dar lugar a una nueva era que
permita el control en la línea de cultivo de la mala hierba de forma más económica y a la
automatización de la operación. El control preciso de la mala hierba es un reto importante para
este grupo, por ello tenemos previsto seguir trabajando en esta línea.Automation of individual crop plant care in commercial vegetable crop fields has increased
practical feasibility and improved efficiency and economic benefit. Its systems approach is taken
in the mechanization engineering design by the incorporation of precision sensing techniques.
The objective of this study was design-sensing capabilities in an implement for measuring plant
spacing under different test conditions: laboratory and field. For that proposal, a photoelectric
transmission barrier, by using an optical light curtain transmitter and receiver, evaluated the
interruption by the tomato stem of the light curtain, being recorded simultaneously in real-time by
a high-speed embedded control system. The optical sensor provided tomato plant detection and
therefore the spacing between tomato plants was determined with accuracy. The use of this
detection system may result in a new era that allow for an online control of aggressive weeds and
the automation of weeding tools, which we plan to pursue through future research.Junta de Andalucía P12-AGR-122
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