141 research outputs found
Anuros del norte de los andes: patrones de riqueza de especies y estado de conservación
Knowledge of Andean anurans is constantly increasing; for this reason, it needs an update. We reviewed scientific literature and museum records to determine the species richness of anurans in the northern Andes and their conservation status based on the IUCN categories. The northern Andes harbor 740 species of anurans, belonging to 13 families and 63 genera. The family with the highest species number was Craugastoridae (334 spp.), followed by Bufonidae (92 spp.), and Centrolenidae (81 spp.). The Cordillera Central of Colombia harbors the highest species richness (199 spp.), while the Cordillera de la Costa Oriental de Venezuela contains the lowest species number (17 spp.). Most species (74%) is endemic to the northern Andes, but no family is endemic to the northern Andes. About 50% species is threatened and 20% is included in the category of deficient data. The species richness patterns in northern Andes might be caused, among other reasons, by historical factors, but also result of sampling lack in some areas
Magnetoresistance and magnetic anisotropy in LaSrCoO film
The magnetic and transport properties of LaSrCoO
film grown on a LaAlO substrate by pulsed-laser deposition are studied. The
properties are found to be influenced by a combined influence of the magnetic
anisotropy and inhomogeneity. Magnetoresistance anisotropy is determined by the
shape anisotropy and the strain-induced magnetic anisotropy due to the
film-substrate lattice interaction. Indications of the temperature-driven spin
reorientation transition from an out-of plane orderded state at low
temperatures to an in-plane ordered state at high temperatures as a result of
competition between the mentioned anisotropy sources are found.Comment: 3 pages, 4 figures, reported at Moscow Int. Symp. on Magnetism (MISM
2002), June 200
Selective Spin-State Switch and Metal-Insulator Transition in \boldmath
Ultra-high resolution synchrotron diffraction data for
throw new light on the metal-insulator transition of Co Ba-cobaltites.
An anomalous expansion of CoO octahedra is observed at the phase transition
on heating, while CoO pyramids show the normal shrinking at the closing of
the gap. The insulator-to-metal transition is attributed to a sudden excitation
of some electrons in the octahedra ( state) into the Co band
(final state). The state in the pyramids does
not change and the structural study also rules out a
orbital ordering at .Comment: Phys. Rev. B (to appear
Voice quality after endoscopic laser surgery and radiotherapy for early glottic cancer: objective measurements emphasizing the Voice Handicap Index
We analyzed the functional outcome and self-evaluation of the voice of patients with T1 glottic carcinoma treated with endoscopic laser surgery and radiotherapy. We performed an objective voice evaluation, as well as a physical, emotional and functional well being assessment of 19 patients treated with laser surgery and 18 patients treated with radiotherapy. Voice quality is affected both by surgery and radiotherapy. Voice parameters only show differences in the maximum phonation time between both treatments. Results in the Voice Handicap Index show that radiotherapy has less effect on patient voice quality perception. There is a reduced impact on the patient’s perception of voice quality after radiotherapy, despite there being no significant differences in vocal quality between radiotherapy and laser cordectomy
Amphibia, Anura, Hylidae, Scarthyla vigilans: range extensions and new state records from Delta Amacuro and Miranda states, Venezuela
Non
Evidence for a Low-Spin to Intermediate-Spin State Transition in LaCoO3
We present measurements of the magnetic susceptibility and of the thermal
expansion of a LaCoO single crystal. Both quantities show a strongly
anomalous temperature dependence. Our data are consistently described in terms
of a spin-state transition of the Co ions with increasing temperature
from a low-spin ground state to an intermediate-spin state without (100K -
500K) and with (>500K) orbital degeneracy. We attribute the lack of orbital
degeneracy up to 500K to (probably local) Jahn-Teller distortions of the
CoO octahedra. A strong reduction or disappearance of the Jahn-Teller
distortions seems to arise from the insulator-to-metal transition around 500 K.Comment: an error in the scaling factor of Eq.(4) and consequently 2 values of
table I have been corrected. The conclusions of the paper remain unchanged.
See also: C. Zobel et al. Phys. Rev. B 71, 019902 (2005) and J. Baier et al.
Phys. Rev. B 71, 014443 (2005
The Obestatin/GPR39 System Is Up-regulated by Muscle Injury and Functions as an Autocrine Regenerative System
Background: Satellite cell activation is orchestrated by several signals, which induce their differentiation into skeletal muscle fibers. Results: Obestatin and the GPR39 receptor exert an autocrine role on the control of myogenesis. Conclusion: Our data indicate that obestatin/GPR39 is an injury-regulated signal that functions as a myogenic regenerative system. Significance: Strategies to enhance obestatin-mediated signaling could be useful in treating trauma-induced muscle injuries and skeletal muscle myopathies
Quality of life in patients with hereditary haemorrhagic telangiectasia (HHT)
Background: There are very few studies about general quality of life parameters, standards for the description of health status and comparison with general population data on patients with Hereditary hemorrhagic telangiectasia (HHT), a rare disease in which epistaxis is a cardinal symptom. Purpose: To assess the quality of life in a population of Spanish patients with HHT and compare it with the general population. Design and methods: Between January 1st 2005 and December 31st 2013, 187 adult patients diagnosed with HHT who were admitted to the HHT Unit of the Hospital Sierrallana, completed on their first visit, the EuroQol 5D-3L (five dimensions and three levels) quality of life descriptive test and the visual analog scale (VAS). The numerical social index value was also determined and the subjective effect of the nasal epistaxis on their quality of life was estimated classified as mild, moderate or severe. Results: Patients with HHT had greater problems than the general population in the five dimensions of the EuroQol 5D-3L, particularly considering pain/discomfort and anxiety/depression. In the VAS and the social index value, patients with HHT also scored lower than the general population, particularly older patients, males, and patients with HHT2. They also had values similar to those of populations with chronic illnesses. The subjective perception of the severity of epistaxis correlated strongly with the VAS and social index values. Conclusions: The quality of life of patients with HHT, estimated using the EuroQol 5D-3L scale, is affected across all dimensions. The scores are similar to those seen in cases of other chronic diseases. Older patients, males and the carriers of the ACVRL1 mutation generally have worse scores on these scales. The VAS and the social index value are index that correlate well with the severity of the clinical symptoms associated mainly with epistaxis
Criterios biológicos y ecológicos: aportes para la identificación, caracterización y delimitación de los humedales interiores de Colombia.
Este producto es elaborado por el Programa Biología de la Conservación y Uso de la Biodiversidad en el marco del convenio 005 (13-014) entre el Instituto Humboldt y el Fondo Adaptación, en este documento se asume los principios generales de los ecosistemas, en los que se caracterizan como sistemas complejos, abiertos, dinámicos e integrados en donde los patrones ecológicas y la diversidad biológica son el resultado de un proceso biogeográfico que a su vez es afectado por procesos antrópicos. Es por ello que los ecosistemas de humedales de interior son considerados unidades funcionales en los que son necesarias las conexiones de la transición de hábitats en función de la pendiente natural (cuenca aguas arriba y abajo), hacia los ecosistemas adyacentes terrestres y dentro del cuerpo de agua (entre las zonas someras y profundas).Bogotá, ColombiaPrograma Biología de la Conservación y Uso de la Biodiversida
- …