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[en] A preliminary information about a Monte Carlo procedure to simulate supersonic flow past a body of a low density plasma in the transition regime is gived. A computer program has been written for a Univac 1108 machine to account for a plasma composed by neutral molecules and positive and negative ions. Different and rather general body geometries can be analyzed. Special attention is payed to the detached shock waves growth in front of the body. (author)
[en] This Report gives preliminary information about a Monte Carlo procedure to simulate supersonic flow past a body of a low density plasma in the transition regime. A computer program has been written for a UNIVAC 1108 machine to account for a plasma composed by neutral molecules and positive and negative ions. Different and rather general body geometries can be analyzed. Special attention is played to tho detached shock waves growth In front of the body. (Author) 30 refs
[en] Abandoned mining sites contain residues from ore processing operations that are characterised by high concentrations of heavy metals. The form in which a metal exists strongly influences its mobility and, thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. In this work, the modified three-stage sequential extraction procedure proposed by the BCR (now the Standards, Measurements and Testing Programme) was applied for the fractionation of Ni, Zn, Pb and Cd in mining wastes from old Pb-Zn mining areas located in the Val d'Aran (NE Spain) and Cartagena (SE Spain). Analyses of the extracts were performed by inductively coupled plasma atomic emission spectrometry and electrothermal atomic absorption spectrometry. The procedure was evaluated by using a certified reference material, BCR-701. The results of the partitioning study indicate that more easily mobilised forms (acid exchangeable) were predominant for Cd and Zn, particularly in the sample from Cartagena. In contrast, the largest amount of lead was associated with the iron and manganese oxide fractions. On the other hand, the applicability of lixiviation tests commonly used to evaluate the leaching of toxic species from landfill disposal (US-EPA Toxicity Characteristic Leaching Procedure and DIN 38414-S4) to mining wastes was also investigated and the obtained results compared with the information on metal mobility derivable from the application of the three-stage sequential extraction procedure
[en] Aim of study: The main objective is to determine the best machine-learning algorithm to classify the stand types of Monteverde forests combining LiDAR, orthophotography, and Sentinel-2 data, thus providing an easy and cheap method to classify Monteverde stand types. Area of study: 1500 ha forest in Monteverde, North Tenerife, Canary Islands. Material and methods: RF, SVML, SVMR and ANN algorithms are used to classify the three Monteverde stand types. Before training the model, feature selection of LiDAR, orthophotography, and Sentinel-2 data through VSURF was carried out. Comparison of its accuracy was performed. Main results: Five LiDAR variables were found to be the most efficient for classifying each object, while only one Sentinel-2 index and one Sentinel-2 band was valuable. Additionally, standard deviation and mean of the Red orthophotography colour band, and ratio between Red and Green bands were also found to be suitable. SVML is confirmed as the most accurate algorithm (0.904, 0.041 SD) while ANN showed the lowest value of 0.891 (0.073 SD). SVMR and RF obtain 0.902 (0.060 SD) and 0.904 (0.056 SD) respectively. SVML was found to be the best method given its low standard deviation. Research highlights: The similar high accuracy values among models confirm the importance of taking into account diverse machine-learning methods for stand types classification purposes and different explanatory variables. Although differences between errors may not seem relevant at a first glance, due to the limited size of the study area with only three plus two categories, such differences could be highly important when working at large scales with more stand types.
[en] Female mules are considered as infertile; however, they could be used as recipients in interspecific embryo transfer. This study reports for the first time how it is possible to obtain the birth of a live Andalusian donkey foal after transfer a donkey embryo to a non-cycling mule. Two non-cycling mules were used as recipients, oestradiol benzoate was administered when donors showed oestrus and long-acting progesterone after ovulation. The mules also received long-acting progesterone every 7 days until 120 days of gestation. One embryo was collected from the two donor jennies and transferred to one of the mules after 5 days of progesterone treatment. Pregnancy was established and maintained after embryo transfer. The pregnant mule carried to term and delivered a live donkey foal after 375 days of pregnancy. In conclusion, non-cycling mules treated with oestradiol benzoate and long-acting progesterone can be successfully used as recipients of donkey embryos, which open new ways for the conservation of endangered donkey species.
[en] The consumption of EVOO in Mediterranean countries has shown beneficial effects. A wide range of evidence indicates that the phenolic compounds present in EVOO are endowed with anti-inflammatory properties. In this work, we evaluated the effects of dietary EVOO and treatment with its phenolic extract (PE) in a model of RA, the collagen-induced arthritis (CIA) in mice. On day 0, DBA-1/J mice were immunized with bovine collagen type II (CII). On day 21, the mice received a booster injection. We have demonstrated that EVOO and its PE decreases joint edema, cell migration, cartilage degradation and bone erosion. Our data indicate that dietary EVOO and PE treatment inhibit JNK, p38 and signal transducer and STAT-3. In addition, both EVOO and PE decrease NF-κB translocation leading to the down-regulation of the arthritic process. These results support the interest of natural diet components in the development of therapeutic products for arthritic conditions.
[es]El consumo de Aceite de oliva virgen extra (AOVE) enlos países mediterráneos ha demostrado tener efectos beneficiosos. Una amplia gama de pruebas indica que los compuestos fenólicos presentes en el AOVE tienen propiedades anti-inflamatorias. En este trabajo, se evaluaron los efectos de AOVE y el tratamiento en dieta de su fracción polifenólica (FP) en un modelo de la artritis reumatoide inducida por colágeno (CIA) en ratones. En el día 0, los ratones DBA-1/J se inmunizaron con colágeno bovino tipo II (CII). En el día 21, los ratones recibieron una inyección de refuerzo. Hemos demostrado que el AOVE y su FP disminuyen conjuntamente el edema, la migración celular, la degradación del cartílago y erosión ósea. Nuestros datos indican que la dieta con AOVE y el tratamiento con FP inhiben JNK, p38 y el transductor de señal y activador de la transcripción 3 (STAT-3). Además, tanto el AOVE como la FP disminuyen la translocación NF-κB que conduce a la mejora del proceso artrítico. Estos resultados apoyan el interés de una dieta con componentes naturales y el desarrollo de productos terapéuticos para desordenes artríticos.
[en] One critical factor for success in characterizing metals polluting mining environments so as to be able to eliminate them and subsequently recover these areas depends upon a speedy and correct response in the analysis of samples. Rapid, simultaneous, multi-element analysis can be undertaken using X-ray fluorescence spectrometry, a versatile, non-destructive analytical technique commonly employed to identify both major and minor elements in samples related to environmental studies. An additional advantage of this technique is the possibility of conducting the analysis directly on solid samples, which is extremely convenient when dealing with environmental samples that are difficult to dissolve, such as soils, sediments and mining wastes. Moreover, in recent years the development of spectrometers equipped with digital-signal processors combined with enlarged X-ray production, using better designs for excitation-detection, has contributed to an improvement in instrumental sensitivity, thus allowing us to detect important polluting elements such as Cd and Pb at trace levels. In this paper the authors describe, on the basis of their own experience, some interesting applications of XRF spectrometry for the analysis of several types of environmental samples related to the study of the dispersion of metals within mining environments: (A) analysis of mining wastes, soils and sediments; (B) analysis of samples of vegetation used as bio indicators or related to phyto remediation studies; and (C) analysis of water samples related to mining operations. (Author) 26 refs.
[en] One of the most frequently issues raised within the management of hospital personnel dosimetry service is the high incidence of the rate evidencing the lack of dosimeter badges replacement in personnel dosimetry on monthly basis. In this respect and following the enforcement of the dispositions ordered by the CSN (Spanish Nuclear Safety Council as Regulatory Agency) concerning the assignment of “administrative dose”, such rate turns currently into a high number of these doses assigned, thus leading to an inefficient monitoring of the personnel dosimetry. In order to achieve a more suitable dosimetry monitoring it is required a more direct and tailored management of personnel dosimetry in every occupationally exposed workers as well as providing with personal and fluent information. The total number of occupationally exposed workers and the diversity and geographical dispersion of the centers under dosimetry monitoring make impossible a customized management without involving substantial resources. With the aim of achieving a more tailored management in an scenario as the one described above as well as reducing the lack of replacement of dosimeter badges in personnel dosimetry on monthly basis and the administrative doses assigned, some measures were implemented in 2009 by applying Communications and Information Technology platforms and further employees management giving as a result a 75% reduction in the rate of non replacement of dosimeter badges in personnel dosimetry.
[es]Una de las cuestiones habitualmente planteada en la gestión de la dosimetría personal hospitalaria es la alta incidencia en la tasa de no recambio mensual de los dosímetros personales y desde la aplicación de la instrucción del Consejo de Seguridad Nuclear (CSN) sobre la asignación de la dosis administrativa, esto supone en la actualidad un alto número de las mencionadas asignaciones; lo que conlleva un deficiente control de la dosimetría personal. Para un mejor control dosimétrico, se requiere realizar una gestión más personalizada y directa de la dosimetría individual de cada uno de los trabajadores expuestos y transmitir una información rápida y personal. Debido al número total de trabajadores expuestos y de la diversidad y dispersión de los centros bajo control dosimétrico se hace imposible este tipo de gestión sin emplear grandes recursos. Para conseguir los objetivos de una gestión más personalizada en un escenario como el descrito, y reducir la tasa de no recambio mensual de los dosímetros personales y de las dosis administrativas asignadas, en el año 2009 se pusieron en marcha en este centro algunas medidas utilizando las plataformas de las Tecnologías de la Información y las Comunicaciones (TIC) y otras de gestión de trabajadores, cuyo resultado ha sido el de la reducción de la tasa de no recambio mensual de los dosímetros personales en un 75 %.