742 research outputs found
Cuidados maternos y neonatales en el periparto de la perra
En la especie canina, son considerados con el término “neonato”, los cachorros desde quenacen hasta que cumplen 4 semanas de edad y se caracterizan por su inmadurez fisiológica, locual los hace totalmente dependientes de la perra o de sus dueños. Por eso, resultaimportante conocer cómo deben ser tratados y manipulados desde el momento en el que seproduce el parto de la hembra. El estado de salud de la madre y el desarrollo de la gestación,parto y posparto, influyen mucho en el futuro y supervivencia de los neonatos. Por tal razón,es fundamental saber la correcta fisiología de la gestación e ir comprobando que se estádesarrollando adecuadamente mediante la ecografía, herramienta que a su vez permitedetectar si existe sufrimiento fetal. La hembra también debe ser cuidada y alimentadacorrectamente por parte de los propietarios. Los veterinarios deben asegurar el bienestar de lahembra durante el parto y actuar en caso de distocia u otra complicación, por si hay querealizar una cesárea o maniobra obstétrica.El conocimiento de los parámetros fisiológicos de los neonatos y las condiciones en las que sedeben mantener tras el parto, permiten realizar los cuidados neonatales básicos apropiados.Además, es conveniente llevar a cabo una evaluación de viabilidad neonatal (test de Apgar)para evaluar rápidamente la supervivencia de los cachorros nada más nacer y así poderanticiparse a posibles complicaciones y reducir la mortalidad. También es preciso encalostrar alos neonatos antes de las 48 horas de vida, para que obtengan la inmunidad pasiva yposteriormente seguir con la lactancia hasta el destete al mes de edad aproximadamente. Launión del neonato con la madre se refuerza en la lactancia y favorece el desarrollo delcachorro.<br /
Nuevo registro del género Dinothrombium (Acari: Parasitengona: Trombidiidae) como parásito de Syspira longipes (Araneae: Miturgidae)
ResumenSe registra como nueva la relación parásita del ácaro Dinothrombium oparbellae (André, 1949) (Acari: Trombidiidae) con la araña Syspira longipes Simon, 1895 (Araneae: Miturgidae) en Baja California Sur, México.AbstractA new parasitic relationship between the mite Dinothrombium oparbellae (André, 1949) (Acari: Trombidiidae) and the spider Syspira longipes Simon, 1895 (Araneae: Miturgidae) in Baja California Sur, Mexico is recorded
Quality production and sustainable development: the case of Merina de Grazalema Sheep cheese
This paper focus on the innovations made by local actors in the production and marketing of Merina de Grazalema Sheep Cheese, studying how these changes may improve or not the sustainability of Sierra de Grazalema as
an agro-ecosystem. These innovations answer to production system
and organization patterns within the supply chain, they seek to confront
a new agro-food context. This new context has been unfolded
by changes in three main elements of the equation:
(1) new EU policies,
(2) Globalization ofthe markets, and new consumption patterns. Merina de Gra lema. We found that the low scale and the high artisan level of production have been the key to the construction of positive answer
to this new context, and that the materialization of these answers is highly diversified
SPIE OPTO, 2018
Indium-doped ZnO bulk crystals grown by the hydrothermal method are highly-conductive, with resistivity at 0.01 Ωcm at room temperature as revealed by Hall-effect measurement. In this paper we report on structural and optical properties of these crystals. The grown In:ZnO crystals have been studied by high resolution X-ray diffraction, micro-Raman scattering and low-temperature photoluminescence and cathodoluminescence. It was found that the c lattice parameter of the grown In:ZnO crystal expanded 0.06% with respect to the lithium-doped
ZnO crystal seed, and the In-doped ZnO overgrew the seed crystal pseudomorphically but with high quality crystallinity; the X-ray rocking curves show the FWHM of the Zn face and O faces are only 0.05o and 0.1o; and the indium concentration in the crystal reaches the solubility limit. Raman spectra show strain relaxation gradually from the regrowth interface as well as a weak spectral feature at 723 cm-1. The peak at 312 cm-1 noticed in hydrothermally grown In:ZnO nanostructures does not appear in our In-doped crystals, indicating that this peak may be associated with specific defects (e.g. surface related) of the nanostructures. Photoluminescence measurements show that an indium donor bound exciton peak I9 (In0X) is the dominant peak in the PL spectrum, located at 3.3586 eV on the zinc face and 3.3577 eV on the oxygen face. Both of them deviated from the consensus literature value of 3.3567 eV, probably due to strain in the crystal induced by impuritie
About the interaction between a laser beam and group IV nanowires: a study of the electromagnetic field enhancement in homogeneous and heterostructured nanowires
The optical properties of semiconductor nanowires (NWs) are object of study
because they are the building blocks of the future nanophotonic devices. The
high refractive index and its reduced dimension, make them suitable for
photon engineering. The study of the interaction between NWs and visible
light has revealed resonances of the light absorption/scattering by the NWs.
Micro-Raman spectroscopy is used as a characterization method of semiconductor
NWs. The relation between the Raman intensity and the incident
electromagnetic (EM) field permits to study the light/NW interaction through
the micro-Raman spectra of individual NWs. As compared to either metallic
or dielectric NWs, the semiconductor NWs add additional tools to modify its
interaction with light, for example, the composition, the presence of
heterostructures, both axial and radial, doping, and the surface morphology.
One presents herein a study of the optical response of group IV semiconductor
NWs to visible photons. The study is experimentally carried out through the micro-Raman spectroscopy of different group IV NWs, both homogeneous and heterostructured (SiGe/Si), and the results are analyzed in terms of the EM modeling of the light/NW interaction using finite element methods (FEMs). The heterostructures are seen to produce additional resonances allowing new photonic capacities to the semiconductor NWs.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref VA293U13
Electromagnetic interaction between a laser beam and semiconductor nanowires deposited on different substrates: Raman enhancement in Si Nanowires
Producción CientíficaRaman scattering of Si nanowires (NWs) presents antenna effects. The
electromagnetic resonance depends on the electromagnetic coupling of the system
laser/NW/substrate. The antenna effect of the Raman signal was measured in individual
NWs deposited on different substrates, and also free standing NWs in air. The one
phonon Raman band in NWs can reach high intensities depending on the system
configuration; values of Raman intensity per unit volume more than a few hundred
times with respect to bulk substrate can be obtained.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA302U13
Consulta preanestésica telefónica pediátrica versus presencial
The telephone pediatric pre-anesthetic assessment consultation is a perfectly valid alternative to the face-to-face consultation, it arose timidly as a response to the current covip-19 pandemic, solving the most important problem: the spread of the virus. Over time, it has found a place in pediatric pre-anesthetic evaluation given the excellent results obtained (patient and staff safety, comfort, economy and saving time for the patient without a decrease in the quality of care). We discuss our way of proceeding.La consulta de valoración preanestésica pediátrica telefónica es una alternativa perfectamente válida a la consulta presencial, surgió tímidamente como respuesta a la actual pandemia de covip-19, resolviendo el problema más importante: la propagación del virus. Con el tiempo, ha encontrado un lugar en la evaluación preanestésica pediátrica dados los excelentes resultados obtenidos (seguridad del paciente y del personal, comodidad, economía y ahorro de tiempo para el paciente sin disminución de la calidad de la atención). Comentamos nuestra forma de proceder
¿Qué Método Utilizar Para Estimar la Temperatura estática de una formación de Petróleo?
Conocer la temperatura estática de una formación de petróleo es importante a la hora de evaluar y terminar un pozo. Existe una gran variedad de métodos para la determinación de esta temperatura. Cada método utiliza hipótesis y simplificaciones distintas que llevan a estimaciones diferentes, en algunos casos bastante alejadas del valor real. Esto hace difícil saber qué método utilizar. En este trabajo, se aplican los métodos de cálculo más comunes - Horner (HM), flujo radial y esférico (SRM), de las dos medidas (TLM) y de fuente de calor cilíndrica (CSM)- a cuatro pozos distintos. Se describe cómo aplicarlos en casos reales. Se presta especial atención a establecer los datos necesarios en cada caso: propiedades termo-físicas y número de medidas, y se proporcionan criterios para estimarlos en caso de no conocer su valor real. Como conclusiones a este trabajo se presentan una serie de pautas que permiten seleccionar el método de cálculo más conveniente en función de la información de que se dispong
Thermal and mechanical issues of high-power laser diode degradation
A computational model for the evaluation of the thermomechanical effects that give rise to the catastrophic optical damage of laser diodes has been devised. The model traces the progressive deterioration of the device running in continuous wave conditions. The local heating of the active layer locally leads to the onset of the plastic regime. As a result, dislocations and threads of dislocations grow across the active layers and lead to rapidly growing temperatures in the quantum well. The poor power dissipation under these conditions has been identified as the key factor driving the final degradation of the laserSpanish Government (ENE2014-56069-C4-4-R) and Junta de Castilla y León (VA29U13 and VA081U16). J.L. Pura wishes to acknowledge a grant by the FPU program of the Spanish Government (FPU14/00916
Thermomechanical issues of high power laser diode catastrophic optical damage
Catastrophic optical damage (COD) of high power laser diodes is a crucial factor limiting
ultra high power lasers. The understanding of the COD process is essential to improve the
endurance of the high power laser diodes. COD is observed as a process in which the active
part of the laser diode is destroyed, forming characteristic defects, the so called dark line
defects (DLDs). The DLDs are formed by arrays of dislocations generated during the laser
operation. Local heating associated with non-radiative recombination is assumed to be at the
origin of the COD process. A summary of the methods used to assess the COD, both in real
time and post-mortem is presented. The main approaches developed in recent years to model
the heat transport in the laser structures under non homogeneous temperature distribution are
overviewed. Special emphasis is paid to the impact of the low dimensionality of QWs in two
physical properties playing a major role in the COD process, namely, thermal conductivity
and mechanical strength. A discussion about the impact of the nanoscale in both physical
properties is presented. Finally, we summarize the main issues of the thermomechanical
modelling of COD. Within this model the COD is launched when the local thermal stresses
generated around the heat source overcome the yield stress of the active zone of the laser. The
thermal runaway is related to the sharp decrease of the thermal conductivity once the onset of
plasticity has been reached in the active zone of the laser.Junta de Castilla y León (Projects VA081U16 and VA283P18)Spanish Government (ENE 2014-56069-C4-4-R, ENE 2017-89561-C4-3-R, FPU programme 14/00916)
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