1,029 research outputs found

    Trends of Rural Tropospheric Ozone at the Northwest of the Iberian Peninsula

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    Tropospheric ozone levels around urban and suburban areas at Europe and North America had increased during 80's–90's, until the application of NOx reduction strategies. However, as it was expected, this ozone depletion was not proportional to the emissions reduction. On the other hand, rural ozone levels show different trends, with peaks reduction and average increments; this different evolution could be explained by either emission changes or climate variability in a region. In this work, trends of tropospheric ozone episodes at rural sites in the northwest of the Iberian Peninsula were analyzed and compared to others observed in different regions of the Atlantic European coast. Special interest was focused on the air quality sites characterization, in order to guarantee their rural character in terms of air quality. Both episodic local meteorological and air quality measurements along five years were considered, in order to study possible meteorological influences in ozone levels, different to other European Atlantic regions

    CENTESIL: An independent Research Centre on Polysilicon

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    The tremendous expansion of the photovoltaic technology and its relative avidity for silicon is producing a dramatic change in the polysilicon industry structure, increasing the efforts to produce a low cost, high quality Solar Silicon. In this context, the Centro de Tecnología del Silicio Solar (CENTESIL) was founded in 2006 as a private-public partnership venture, and is currently building a 50 t/a pilot plant for silicon purification following the chlorosilane route. Although an advanced state of the art technology has been selected as first choice, the purpose is to be able to undertake developments in any topic that has the potential to reduce the cost effectively. Additionally, the project includes facilities for monocrystalline growth and wafering, and also the solar cell processing line of the Instituto de Energía Solar, so that it will cover the whole value chain from feedstock to solar cell

    A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere

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    A catalog of optical warps of galaxies is presented. This can be considered complementary to that reported by Sanchez-Saavedra et al., with 42 galaxies in the northern hemisphere, and to that by Reshetnikov & Combes, with 60 optical warps. The limits of the present catalog are: logr25 > 0.60, B_{t} < 14.5, delta(2000) < 0, -2.5 < t < 7. Therefore, lenticular galaxies have also been considered. This catalog lists 150 warped galaxies out of a sample of 276 edge-on galaxies and covers the whole southern hemisphere, except the Avoidance Zone. It is therefore very suitable for statistical studies of warps. It also provides a source guide for detailed particular observations. We confirm the large frequency of warped spirals: nearly all galaxies are warped. The frequency and warp angle do not present important differences for the different types of spirals. However, no lenticular warped galaxy has been found within the specified limits. This finding constitutes an important restriction for theoretical models.Comment: 12 pages, 6 figures, to be published in Astronomy and Astrophysic

    Los depósitos de ceniza volcánica del Pleistoceno Superior-Holoceno de la región de Tafí del Valle-Cafayate, noroeste de Argentina

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    [EN]We identified volcanic ash deposits, whose thickness can exceed sometimes the 4 m, in the southeastern margin of La Puna and neighbouring areas (Provinces of Tucuman and Salta, Argentina). These Late Pleistocene and Holocene deposits show the existence of a highly explosive volcanism only some few thousand years ago, without comparison with any historical volcanic episode in northwestern Argentina. We have characterized the size distribution of ash (laser diffraction), morphology of particles (SEM), mineralogy (XRD) and the geochemistry of major and trace elements in bulk sample using mass spectrometry (HR-ICP-MS). The information provided by these deposits is of great interest to size adequately the geochemical impact models of ashfall in future volcanic eruptions in the Central Volcanic Zone of the Andes, quantifying the contribution of volcanic ash to the regional geochemical balances, both with respect to nutrients (e.g., Ca and Fe) and potentially toxic elements (e.g., As and F), among other elements of interest.[ES] Se han localizado diversos depósitos de ceniza volcánica, cuyos espesores llegan a superar en ocasiones los 4 m al suroeste de La Puna y áreas limítrofes (Provincias de Tucumán y Salta, Argentina). Estos depósitos son de edad Pleistoceno Superior y Holoceno y muestran la existencia hace pocos miles de años de volcanismo altamente explosivo, sin comparación con ningún episodio volcánico histórico en el noroeste de Argentina. Se han caracterizado la distribución granulométrica de la ceniza (difracción laser), la morfología de las partículas (microscopía electrónica de barrido), mineralogía (difracción de rayos X) y la geoquímica de elementos mayores y trazas en muestra total mediante espectrometría de masas (HR-ICP-MS). La información suministrada por estos depósitos tiene gran interés a la hora de dimensionar los modelos de impacto geoquímico de la caída de ceniza de futuras erupciones volcánicas en la Zona Volcánica Central de los Andes, cuantificando la contribución de la ceniza volcánica a los balances geoquímicos regionales, tanto por lo que respecta a nutrientes (p. ej., Ca y Fe), como de elementos potencialmente tóxicos (p. ej., As y F), entre otros elementos de interés.Agradecemos el apoyo técnico del labGEOTOP (infraestructura cofinanciada por FEDER, CSIC08-4E-001) del ICTJA-CSIC; de los Grupos PEGEFA (2009-SGR-972) y GEOVOL y fue financiado por el Proyecto QUECA (CGL2011-23307).Peer reviewe

    Adipose-Derived Fatty Acid-Binding Proteins Plasma Concentrations Are Increased in Breast Cancer Patients.

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    BACKGROUND: Adipose tissue is an endocrine organ that could play a role in tumor progression via its secreted adipokines. The role of adipose-derived fatty acid-binding protein (FABP) 4 and FABP5 in breast cancer is presently under study, but their circulating levels in this pathology are poorly known. We analyzed the blood concentrations of FABP4 and FABP5 in breast cancer patients to determine whether there is an association between them and breast cancer. MATERIALS AND METHODS: We studied 294 women in the oncology department with a family history of breast cancer; 198 of the women had breast cancer, and 96 were healthy controls. The levels of FABP4, FABP5, lipid profile, standard biochemical parameter, and high-sensitivity C-reactive protein (hsCRP) were determined. We analyzed the association of FABP4 and FABP5 with breast cancer, while adjusting for demographic, anthropometric, and biochemical parameters. RESULTS: Breast cancer patients had a 24.8% (p < .0001) and 11.4% (p < .05) higher blood concentration of FABP4 and FABP5, respectively. Fatty acid-binding protein 4 was positively associated with age, body mass index (BMI), FABP5, very-low-density lipoprotein cholesterol (VLDLc), non-high-density lipoprote in cholesterol (non-HDLc), Apolipoprotein B 100 (ApoB100), triglycerides, glycerol, glucose, and hsCRP (p < .05), and was negatively associated with HDLc (p < .005) in breast cancer patients. Fatty acid-binding protein 5 was positively associated with BMI, FABP4, VLDLc, triglycerides, glycerol, and hsCRP (p < .05), and was negatively associated with HDLc and Apolipoprotein AI (ApoAI) (p < .05) in breast cancer patients. Using a logistic regression analysis and adjusting for age, BMI, hsCRP, non-HDLc, and triglycerides, FABP4 was independently associated with breast cancer (odds ratio [OR]: 1.091 [95% CI: 1.037-1.149]). Moreover, total cholesterol, VLDLc, non-HDLc, ApoB100, triglycerides, and hsCRP were significantly increased in breast cancer patients (p < .005). In contrast, the non-esterified fatty acids concentrations were significantly decreased in breast cancer patients (p < .05). CONCLUSION: Circulating FABP4 and FABP5 levels were increased in breast cancer patients compared with controls. The positive association of FABP4 with breast cancer was maintained after adjusting for important covariates, while the association with FABP5 was lost. Our data reinforce the role of adipose tissue and their adipokines in breast cancer. Despite these data, further studies must be performed to better explain the prognosis or diagnostic value of these blood parameters and their possible role in breast cancer. IMPLICATIONS FOR PRACTICE: We focus on the effect of adipose tissue on cancer, which is increasingly recognized. The association between adipocyte-derived adipokines and breast cancer opens new diagnosis and therapy perspectives. In this study, we provide original data concerning FABP4 and FABP5 plasma concentrations in breast cancer patients. Compared to control group, breast cancer patients show higher FABP4 and FABP5 blood levels. Our data suggest that, particularly, circulating FABP4 levels could be considered a new independent breast cancer biomarker. Our work translates basic science data to clinic linking the relationship between adipose tissue and lipid metabolism to breast cancer

    Differential antibody response against conformational and linear epitopes of the L1 protein from human papillomavirus types 16/18 is generated in vaccinated woman or with different exposures to the virus

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    Antibodies against human papillomavirus (HPV) L1 protein are associated to past infections and related to the evolution of the disease, while antibodies against L1 virus like particles (VLPs-L1) are used to follow the neutralizing immune response in vaccinated women. In this study, sera antibodies against conformational and linear epitopes of L1 protein from HPV16/18 were evaluated to discriminate HPV vaccinated women from those naturally infected or with uterine cervical lesions. The VLPs-L1 from HPV16/18 generated in baculovirus were purified by CsCl gradient and linear L1 protein obtained by denature VLPs. Serum antibodies against VLPs-L1 and L1 from vaccinated women or with different exposures to the virus were measured by ELISA. Regresion and ROC analysis were carried out to evaluete the test performance to discriminate the different women populations. The results showed that antibodies against VLPs-L1-16/18 highly associated with vaccinated women (OR=2.11e+08 and 57.74, respectively), but not associations were observed with natural infected women or with cervical lesions. However, antibodies against L1-16/18 showed high associations with vaccinated women (OR= 101.33 and 37.91, respectively) (p≤ 0.05), but also associations of these antibodies were observed with the cervical cancer (CC) group (OR= 3.33 and 5.65, respectively). The ROC analysis showed that antibodies against VLPs-L1 and L1 16/18 were highly effective to detect vaccinated women (AUC= 0.96, 0.91. 0.80 and 0.78, respectively), with high sensitivity for HPV16 (100% and 86.3%), and moderate for HPV18 (63.6%). However, anti-L1 antibodies had the best test performance to discriminate the cervical intraepithelial neoplasia grade 3 (CIN3)/CC group from controls (AUC= 0.67 HPV16 and 0.63 HPV18), with low sensitivity (15% to 20%, respectively) and high specificity (96% and 92%, respectively). In conclusion, our results suggested that anti-VLPs-L1 16/18 antibodies are highly efficient to detect vaccinated women, but anti-L1 antibodies are better to discriminate CIN3/CC among the general population

    On the origin of [Ne II] emission in young stars: mid-infrared and optical observations with the Very Large Telescope

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    {Abridged version for ArXiv}. We provide direct constraints on the origin of the [Ne II] emission in 15 young stars using high-spatial and spectral resolution observations with VISIR at the VLT that allow us to study the kinematics of the emitting gas. In addition we compare the [Ne II] line with optical forbidden lines observed for three stars with UVES. The [Ne II] line was detected in 7 stars, among them the first confirmed detection of [Ne II] in a Herbig Be star, V892 Tau. In four cases, the large blueshifted lines indicate an origin in a jet. In two stars, the small shifts and asymmetric profiles indicate an origin in a photo-evaporative wind. CoKu Tau 1, seen close to edge-on, shows a spatially unresolved line centered at the stellar rest velocity, although cross-dispersion centroids move within 10 AU from one side of the star to the other as a function of wavelength. The line profile is symmetric with wings extending up to about +-80 km/s. The origin of the [Ne II] line could either be due to the bipolar jet or to the disk. For the stars with VLT-UVES observations, in several cases, the optical forbidden line profiles and shifts are very similar to the profile of the [Ne II] line, suggesting that the lines are emitted in the same region. A general trend observed with VISIR is a lower line flux when compared with the fluxes obtained with Spitzer. We found no correlation between the line full-width at half maximum and the line peak velocity. The [Ne II] line remains undetected in a large part of the sample, an indication that the emission detected with Spitzer in those stars is likely extended.Comment: Accepted for publication in Astronomy & Astrophysics; revised version: corrected minor typos, corrected center values (col 3) for CoKuTau1 in Table

    The Boom of cohabitation in Colombia and in the Andean Region : social and spatial patterns

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    In this chapter we use census microdata to document the rise in cohabitation in Colombia and in the Andean countries of Ecuador, Bolivia, Perú and Venezuela over the last four decades. We use multilevel logistic regression models to examine the effect of individual and contextual variables on cohabitation. We show the individual and contextual effects of social stratification, ethnicity and religion on cohabitation. Cohabitation levels follow a negative gradient with education and vary according to ethnic background. The Bolivian, Ecuadorian and Peruvian censuses reveal that the two largest ethnic groups (i.e. the Quechua and Aymara) have, controlling for other characteristics, the lowest incidence of cohabitation. By contrast, Afro-American populations show the highest levels of cohabitation. The joint use of individual- and contextual-level explanatory variables is sufficient to account for the majority of Bolivia's internal diversity regarding cohabitation, but not sufficient to account for the internal diversity identified in Colombia, Peru or Ecuador. Even after controls, residence in the Andes mountain areas continues to be a factor associated with lower levels of cohabitation. This invites further investigations on how the institutionalization of marriage occurred in the Andes
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