344 research outputs found
Desarrollo didáctico de las nociones de "coherencia" y "cohesión" y su aplicación a los estudios de traducción
El presente artÃculo pretende revisar desde un punto de vista teórico y didáctico las nociones de coherencia y de cohesión, asà como su relación con otros conceptos cercanos, como son los de discurso y texto. AsÃ, partiremos desde una aproximación lingüÃstica a estos conceptos para finalizar en la utilidad que ambos tienen como herramienta de análisis lingüÃstico no sólo en la comprensión de un texto origen, sino también en la producción de un texto meta
José MarÃa Bravo (ed.), A New Spectrum of Translation Studies, Valladolid: Secretariado de Publicaciones e Intercambio Editorial de la Universidad de Valladolid, 2004, 392 pp.
Astronomical Site Ranking Based on Tropospheric Wind Statistics
We present comprehensive and reliable statistics of high altitude wind speeds
and the tropospheric flows at the location of five important astronomical
observatories. Statistical analysis exclusively of high altitude winds point to
La Palma as the most suitable site for adaptive optics, with a mean value of
22.13 m/s at the 200 mbar pressure level. La Silla is at the bottom of the
ranking, with the largest average value 200 mbar wind speed(33.35 m/s). We have
found a clear annual periodicity of high altitude winds for the five sites in
study. We have also explored the connection of high to low altitude atmospheric
winds as a first approach of the linear relationship between the average
velocity of the turbulence and high altitude winds (Sarazin & Tokovinin 2001).
We may conclude that high and low altitude winds show good linear relationships
at the five selected sites. The highest correlation coefficients correspond to
Paranal and San Pedro Martir, while La Palma and La Silla show similar high to
low altitude wind connection. Mauna Kea shows the smallest degree of
correlation, which suggests a weaker linear relationship. Our results support
the idea of high altitude winds as a parameter for rank astronomical sites in
terms of their suitability for adaptive optics, although we have no evidence
for adopting the same linear coefficient at different sites. The final value of
this linear coefficient at a particular site could drastically change the
interpretation of high altitude wind speeds as a direct parameter for site
characterization.Comment: 18 pages, 5 figures. Accepted in MNRA
Stand-alone lumbar cage subsidence: A biomechanical sensitivity study of cage design and placement.
Background and objective: Spinal degeneration and instability are commonly treated with interbody fusion cages either alone or supplemented with posterior instrumentation with the aim to immobilise the segment and restore intervertebral height. The purpose of this work is to establish a tool which may help to understand the effects of intervertebral cage design and placement on the biomechanical response of a patient-specific model to help reducing post-surgical complications such as subsidence and segment instability.
Methods: A 3D lumbar functional spinal unit (FSU) finite element model was created and a parametric model of an interbody cage was designed and introduced in the FSU. A Drucker–Prager Cap plasticity formulation was used to predict plastic strains and bone failure in the vertebrae. The effect of varying cage size, cross-sectional area, apparent stiffness and positioning was evaluated under 500 N preload followed by 7.5 Nm multidirectional rotation and the results were compared with the intact model.
Results: The most influential cage parameters on the FSU were size, curvature congruence with the endplates and cage placement. Segmental stiffness was higher when increasing the cross-sectional cage area in all loading directions and when the cage was anteriorly placed in all directions but extension. In general, the facet joint forces were reduced by increasing segmental stiffness. However, these forces were higher than in the intact model in most of the cases due to the displacement of the instantaneous centre of rotation. The highest plastic deformations took place at the caudal vertebra under flexion and increased for cages with greater stiffness. Thus, wider cages and a more anteriorly placement would increase the volume of failed bone and, therefore, the risk of subsidence.
Conclusions: Cage geometry plays a crucial role in the success of lumbar surgery. General considerations such as larger cages may be applied as a guideline, but parameters such as curvature or cage placement should be determined for each specific patient. This model provides a proof-of-concept of a tool for the preoperative evaluation of lumbar surgical outcomes
Intensification of UV-C tertiary treatment : Disinfection and removal of micropollutants by sulfate radical based Advanced Oxidation Processes
This study explores the enhancement of UV-C tertiary treatment by sulfate radical based Advanced Oxidation Processes (SR-AOPs), including photolytic activation of peroxymonosulfate (PMS) and persulfate (PS) and their photocatalytic activation using Fe(II). Their efficiency was assessed both for the inactivation of microorganisms and the removal or micropollutants (MPs) in real wastewater treatment plant effluents. Under the studied experimental range (UV-C dose 5.7-57 J/L; UV-C contact time 3 to 28 s), the photolysis of PMS and PS (0.01 mM) increased up to 25% the bacterial removal regarding to UV-C system. The photolytic activation of PMS led to the total inactivation of bacteria (approximate to 5.70 log) with the highest UV-C dose (57 J/L). However, these conditions were insufficient to remove the MPs, being required oxidant's dosages of 5 mM to remove above 90% of carbamazepine, diclofenac, atenolol and triclosan. The best efficiencies were achieved by the combination of PMS or PS with Fe(II), leading to the total removal of the MPs using a low UV-C dosage (19 J/L), UV-C contact time (9 s) and reagent's dosages (0.5 mM). Finally, high mineralization was reached ( > 50%) with photocatalytic activation of PMS and PS even with low reagent's dosages.Peer reviewe
MEASURING PARTICIPATION: A COMPARATIVE STUDY of CITIZEN ENGAGEMENT PROCESSES in URBAN PLANNING
Prevalence of Intestinal Parasites in Endangered Ashy Red Colobus Monkeys (Piliocolobus tephrosceles) in Tanzania
Intestinal parasites constitute one of the most frequent causes of gastrointestinal diseases in primates, directly affecting their health. We sampled 3 populations of the Endangered ashy red colobus monkey (Piliocolobus tephrosceles) with different levels of anthropogenic disturbance in Tanzania. We collected faecal samples (n=157) soon after defecation and fixed them in situ in 70% ethanol. We then re-fixed half of each sample in MIF (merthiolate iodine formaline) for microscopic study and saved the rest for molecular analysis. We examined helminth eggs, larvae and protozoan cysts using a light microscope after faecal sedimentation. We analysed samples positive for Giardia using Polymerase Chain Reaction (PCR) to determine genotypes. The overall prevalence of protozoan and helminth infection was 94.3% (148/157), with 64.9% (96/148) being infected by 1 species, 25.7% (38) by 2 species, and 9.5% (14) by 3 or more species. We detected 8 species of intestinal parasites: Ancylostoma sp. (13.4%), Trichuris trichiura (3.8%), Strongyloides stercoralis rhabditoid larvae (2.5%), Entamoeba chatonni (82.8%), Iodamoeba butschlii (14%), Endolimax nana (4.5%), Blastocystis hominis (2.5%) and Giardia duodenalis (14%). These species were detected in different combinations in the 3 areas, while Giardia was detected in only 1 area. The molecular analysis of positive Giardia samples showed that all of them belonged to assemblage B, which could also infect humans. However, we could not identify an exclusively anthropogenic origin of the parasitic species found. Our study contributes to our knowledge of parasitic infections in ashy monkeys in Tanzania, allowing us to assess their health status and disease risk, which in turn will help us design more successful conservation strategies for this Endangered primate in Tanzani
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