1,327 research outputs found
Bursitis del psoas-ilíaco
La bolsa serosa del psoas-ilíaco es una estructura anatómica bien definida, habitualmente
presente en el adulto. La comunicación entre dicha bolsa y la articulación de la cadera
se asocia frecuentemente a la coxartria. Presentamos un caso de agrandamiento de la
bolsa serosa del psoas ilíaco en una paciente de 69 años. El diagnóstico de sospecha se estableció
por la presencia de una masa inguinal y dolor de cadera. La ecografía y la T.A.C. confirmaron
el diagnóstico. Tras la punción de la bolsa y la instilación de corticoides hemos obtenido la
remisión de los síntomas.The iliopsoas bursa is a well-defined anatomic structure rarely absent in adults.
Communication existing between the iliopsoas bursa and the hip joint is frequently associated
with preexisting hip arthrosis. We present a case of iliopsoas bursa enlargement in a 69-yearold
woman. The diagnosis was suspected by the presence of inguinal mass and hip pain. Echography,
and later computed tomography confirmed it. The patient was successfully treated with
aspiration of cyst content and steroid instillation
Detection of Leishmania infantum kinetoplast DNA by Real Time PCR in hair of wild rabbits
The study of potential wild mammal reservoirs is necessary for the surveillance of leishmaniosis, as Leishmania protozoans have been isolated from a wide range of wild and domestic animal species, including Leporidae. Recently, it has been demonstrated that both hares and wild rabbits can act as sylvatic reservoirs of Leishmania. In Spain, most of the research involving wild rabbits has been developed in the central area of Madrid and in the southeastern Mediterranean coast. We studied the presence of Leishmania infantum in 116 wild rabbits (Oryctolagus cuniculus) captured in Santovenia de Pisuerga, Valladolid, Spain. Hair samples were analyzed by real time PCR. L. infantum kinetoplast DNA (kDNA) was detected and quantified in 4 out of 116 analyzed animals. The estimated number of parasites obtained were quite variable, ranging from 2.60 to 276.60. Hair samples can be collected by non-invasive methods, being a proper sample for Leishmania detection in wild Leporidae, which have an important role as reservoirs of Leishmania. Our findings enhance the need for more extensive studies in different geographical areas.S
Ozone as oxidation agent in cyclic activation of biochar
Granular activated carbons were produced from grape seed biochar by cyclic activation with ozone. In each cycle, char was first oxidized by exposure to ozone and then subjected to high temperature in inert atmosphere to desorb oxygen groups formed. The study assessed the influence of operating conditions in the development of porosity, from a starting biochar with narrow microporosity (SBET: 47 m2 g− 1, SDA: 505 m2g− 1) prepared by flash pyrolysis of grape seed at 800 °C. The variables studied were the number of cycles applied and the oxidation and desorption temperatures (250–275 and 850–950 °C, respectively). High oxidation temperatures led to higher burn-off, which was also found to increase with the number of activation cycles. The burn-off needed to achieve a high surface area was lower than in conventional physical activation. After 7–9 activation cycles, activated carbons with SBET higher than 1200 m2 g− 1 and SDA above 1500 m2 g− 1 were obtained. The use of ozone resulted in mainly microporous activated carbons (0.37–0.52 cm3 g− 1) with very low contribution of mesopores (< 0.04–0.07 cm3 g− 1). The mean micropore size increased with the number of activation cycles due to pore widening, while mesopore mean size decreased along the cycles. The activated carbons showed a unique granular morphology with a hollow core and a porous shell, which is maintained even after 10 activation cyclesThe authors greatly appreciatefinancial support from the Spanish Ministerio de Ciencia e Innovación (CTQ2012-32821
Preparation of granular activated carbons from grape seeds by cycles of liquid phase oxidation and thermal desorption
Activation of grape seed char upon successive cycles of liquid phase oxidation followed by high temperature desorption permits a tailored development of porosity. In this work three different oxidants (HNO3, H 2O2, and (NH4)2S2O 8), have been tested and the desorption temperature has been varied within 850-950 C upon 10 activation cycles. A high increase of BET surface area was observed in the first five cycles with HNO3 as oxidizing agent giving rise to values higher than 1200 m2 g- 1 at around 50% burn-off. Activation with H2O2 and (NH 4)2S2O8 led to a significantly lower development of surface area, with 600 and 800 m2 g- 1 respectively at that burn-off. The analysis of the pore size distribution showed that porosity was generated through the creation of new micropores and widening of existing ones upon activation with HNO3 and (NH4) 2S2O8, whereas H2O2 mostly led to the widening of the narrow micropores already existing in the starting char. The activated carbons obtained are essentially microporous, with some small contribution of mesoporosity in the HNO3 series (V micro = 0.69 cm3 g- 1; Vmeso = 0.07 cm3 g- 1). SEM images showed that the activated carbons maintained the granular morphology of the seeds after 10 cycles showing a hollow core structure with a wall thickness of about 200 μmThe authors greatly appreciate the financial support from the Spanish Ministerio de Ciencia e Innovación (CTQ2009-09983
Granular mesoporous activated carbons from waste tires by cyclic oxygen chemisorption-desorption
This document is the accepted manuscript version of a published work that appeared in final form in Industrial and Engineering Chemistry Research, © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/ie201499hActivation upon cyclic oxygen chemisorption-desorption has proved to be an efficient way to develop porosity at low burn off from waste tires char. In this work the influence of particle size, desorption temperature, and the number of cycles is studied. Highest values of burnoff and specific surface area (S BET) are obtained for the largest particle diameter (3 mm average) and at intermediate desorption temperature (650 °C). In these conditions S BET values around 500 m 2/g can be achieved at burn-offs of about 30%, and close to 600 m 2/g at around 45% burnoff, with a mean pore size of 10 nm and a micropore volume close to 0.08 cm 3/g. Although the surface area is moderate, the low burnoff and high S BET/burnoff ratio achieved make it possible to maintain initial granular morphology of the particles even after 20 cycles of activationWe greatly appreciate finantial support from the Spanish Ministerio de Educacion y Ciencia through the project CTQ2009-0998
Porous structure and morphology of granular chars from flash and conventional pyrolysis of grape seeds
This work studies the influence of the operating conditions used in the pyrolysis of grape seeds on the morphology and textural properties of the chars resulting. Flash and conventional (283Kmin-1 heating rate) pyrolysis have been used within a wide range of temperature (300-1000°C). The effect of a pretreatment for oil extraction has also been studied. The porous structure of the chars was characterized by adsorption of N2 at 77K, Ar at 77K and 87K, and CO2 at 273K and mercury intrusion porosimetry. The morphology was analyzed by scanning electron microscopy. All the materials prepared revealed an essentially microporous structure, with a poor or even negligible contribution of mesopores. Increasing pyrolysis temperature led to higher specific surface areas and lower pore size. The highest specific surface area values occurred within 700-800°C, reaching up to 500m2g-1 with pore sizes in the 0.4-1.1nm range. No significant morphological changes were observed upon carbonization so that the resulting chars were granular materials of similar size than the starting grape seeds. The hollow core structure of the chars, with most of the material allocated at the periphery of the granules can help to overcome the mass transfer limitations of most common (solid or massive) granular activated carbons. The chars showed a good mechanical strength during attrition tests. These chars can be potential candidates for the preparation of granular carbons molecular sieve or activated carbons raw materialsThe authors greatly appreciate financial support from the Spanish Ministerio de Ciencia e Innovación (CTQ2009-09983
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