126 research outputs found

    Europa ante el fenómeno de las «sectas»

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    En las sociedades europeas está enraizado el principio según el cual los Estados no deben restringir la libertad de religión o de conciencia, sino que deben mantener la neutralidad. La pluralidad debe entonces ser protegida por las diversas instituciones europeas. El Consejo de Europa y el Parlamento Europeo, como entidades supranacionales, reconocen el derecho fundamental de libertad y tolerancia hacia todas las manifestaciones religiosas. En este trabajo, se describen y se analizan los documentos oficiales elaborados por ambas instituciones en cuanto a la implantación, en el viejo continente, de lo que se denominan sectas y nosotros reconocemos como nuevos movimientos religiosos.In European societies we find the deeply rooted principle according to which States must not restrict freedom of religion or conscience, but should maintain neutrality. Plurality thus must be protected from the various European institutions. As supranational entities, the Council of Europe and the European Parliament recognize the fundamental right of freedom and tolerance towards all religious expressions. This paper describes and analyzes the official documents produced by the two institutions on the implantation, in the old continent, of so-called sects (which we prefer to call new religious movements)

    Comparación de ciclos sub, super y ultracríticos para centrales termosolares

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    El presente proyecto fin de grado tiene como objetivo la comparación de ciclos subcríticos, supercríticos y ultracríticos en centrales termosolares. Para ello se ha realizado un programa que permite calcular las variables termodinámicas de interés (temperatura, presión, entalpía y gasto másico) en los puntos singulares del ciclo de producción de potencia, una vez introducidos los valores que permiten calcular el mismo. El programa calcula a su vez el rendimiento de la central y la potencia neta generada. Además del balance energético de cada ciclo de producción de potencia, el programa permite calcular los parámetros característicos de transferencia de calor de los intercambiadores cerrados que poseen los ciclos, así como sus dimensiones. Se comparan en total diez ciclos: ciclo subcrítico condensado por agua o aire, supercrítico condensado por agua o aire y con un solo o doble recalentamiento y ultracrítico condensado por agua o aire y con un solo o doble recalentamiento, introduciendo en el programa las condiciones propias de cada uno de ellos. Los ciclos subcríticos trabajan con ~125bar en el foco caliente y el vapor alcanza los 540°C. Estos ciclos son los utilizados hasta hoy para centrales termosolares. En los ciclos supercríticos la presión se eleva hasta los 300bar y la temperatura del vapor alcanza los 590°C, mientras que en los ciclos ultracríticos estos parámetros aumentan hasta los 330bar y 630°C. Por tanto, en estos dos últimos casos, se produce una transición continua desde el estado líquido al estado vapor ya que el cambio de fase no se produce a la temperatura de saturación. La utilización de mayores temperaturas permite mejorar la eficiencia que hoy día se tiene con los ciclos subcríticos: ~48% en ultracríticos frente a ~38% en subcríticos. Sin embargo la mayor parte de la mejora se obtiene al aumentar la temperatura a solo 590°C, propia de los supercríticos, con una rendimiento de ~46,5%. Al condensar por aire los ciclos muestran peores resultados, disminuyendo sus rendimientos del orden de un 2%, mientras que los ciclos con doble recalentamiento aumentan su eficiencia en un 0,2%. Los ciclos super y ultracríticos constan de un mayor número de intercambiadores cerrados que los subcríticos. De esta forma, aunque las condiciones sean más extremas en super y ultracríticos, los intercambiadores no se diferencian apenas de los de los ciclos subcríticos ya que la carga se reparte entre un mayor número de ellos.The present project aims for making a comparison between subcritical, supercritical and ultracritical cycles for power towers. To do so, it has been created a program that allows the calculation of some variables (temperature, pressure, enthalpy and flow rate) in the singular points of the power plant cycles, once the values that make possible the calculation have been introduced. This program calculates also the efficiency and the power generated by the plant. Apart from the cycles’ heat balance, the program allows the calculation of the characteristic parameters of the cycles’ feedwater heaters, and also the dimensions of them. In total ten cycles are compared: subcritical with wet and dry condenser cooling, supercritical with wet and dry condenser cooling and with only one and with two reheaters and ultracritical with wet and dry condenser cooling and with one and with two reheaters, introducing to make the comparison the specific thermal conditions of each cycle. Subcritial cycles work with 125bar in the hot focus and the steam reachs 540°C. Nowadays these are the cycles used in power towers. In supercritical cycles the pressure increases to 300bar and the steam reachs 590°C, whereas in ultracritical cycles these parameters increase to 330bar and 630°C. Therefore, in these two last cases, there is a continuous transition from liquid water to steam because of the phase change is not at the saturation temperature. The use of higher temperatures lets improve the efficiency that nowadays subcritical cycles have: ~48% in ultracritical cycles versus ~38% in subcritical. However, most of the improvement can be expected by raising the temperature to only 590°C, typical of supercritical cycles, with an efficiency ~46,5%. With dry condenser cooling, the cycles get worse results, decreasing their efficiency ~2%, whereas cycles with two reheaters increase their efficiency ~0,2%. Supercritical and ultracritical cycles have more feedwater heaters than subcritical cycles. By this way, although the conditions are more extreme in super and ultracritical cycles, there isn´t hardly any differences between super and ultracritical heat exchangers and subcritical heat exchangers because the load is divided in a higher number of them.Ingeniería en Tecnologías Industriale

    The Role of Snow-Related Environmental Variables in Plant Conservation Plans in the Mediterranean Mountains

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    This study aims to analyze the effects that snow cover may have on the survival of one-year-old seedlings from 15 different taxa in the Mediterranean high mountains (Sierra Nevada National Park, SE Spain) in order to have clearer criteria for the planning and management of restoration efforts in these environments. Additionally, the influence of variables that have been scarcely explored up to now is also revised. We use the survival rates of the seedlings observed from the ecological restoration trial as reference values. The survival data analyzed are based on six variables to evaluate their effects. The results confirm that the permanence of snow is a favorable factor for seedlings, independent of the plant community. Contrastingly, a specific type of foundation (stones and rocks) stands out for being clearly unfavorable, regardless of other variables. For both altitude and solar radiation, a worsening of the survival ratio has been observed as they increase. The species’ geographic ranges are all shown to be unfavorable for taxa of a boreo-alpine distribution. Finally, the plant community does not have a significant influence on the survival of seedlings. These results provide novel indications to improve the results of the first stages of restoration work in the Mediterranean high mountains. They are also valuable for the management and cataloging of threatened flora, as well as having direct applications in recovery plans and protection lists.EAFRD (exp. 701/2010/M/00) fundsERDF (exp. 980/2007/M/00) fund

    Advances and Pitfalls of Specialized Pain Care through Public and Private Health Care Providers in Catalonia and the Balearic Islands: A Physician’s Survey

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    Optimal diagnosis and treatment of pain require a multidisciplinary approach that demands considerable coordination and forethought. A cross-sectional physician survey based on an online questionnaire was carried out to assess the adoption of multidisciplinary working patterns, compare the public and private models, and provide an update on the resources and organization of specialized pain care in Catalonia and the Balearic Islands. Active pain practitioners identified through the Catalan Health Service and Pain Society databases were sent an invitation in December 2020. Of the 321 physicians contacted, 91 (28.3%) answered and 71 provided complete responses (commonly anesthesiologists, representing 92 different sites; some worked at public and private sites). Up to 78.7% reported working in pain management teams, but only 53.5% were regularly involved in teaching or research activities. Thus, the proportion of multidisciplinary sites lies somewhere in-between. Median wait times were significantly shorter and within the recommended standards in private practices (e.g., 15 vs. 90 days in public practices for noncancer patients). In turn, private practices were slightly less staffed and equipped, albeit the differences did not reach statistical significance. Respondents made a median of 530 regular and 30 emergency visits per year, of which 190 involved interventional procedures. They offered a wide range of pharmacological and interventional therapies, although psychotherapy and the most sophisticated procedures were only available in <= 50% of sites. Pain clinicians and facilities are reasonably available in Catalonia, but barely more than half are truly multidisciplinary. Public and private practices differ in some aspects; the latter seems to be more accessible, but it is restricted to patients who can afford it. Compared to previous reports, this update shows both advances and outstanding issues. Multidisciplinary care could be expanded by incorporating more psychologists and some interventional procedures. The public practices should reduce wait times

    MGMT methylation may benefit overall survival in patients with moderately vascularized glioblastomas

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    [EN] Objectives To assess the combined role of tumor vascularity, estimated from perfusion MRI, andMGMTmethylation status on overall survival (OS) in patients with glioblastoma. Methods A multicentric international dataset including 96 patients from NCT03439332 clinical study were used to study the prognostic relationships betweenMGMTand perfusion markers. Relative cerebral blood volume (rCBV) in the most vascularized tumor regions was automatically obtained from preoperative MRIs using ONCOhabitats online analysis service. Cox survival regression models and stratification strategies were conducted to define a subpopulation that is particularly favored byMGMTmethylation in terms of OS. Results rCBV distributions did not differ significantly (p > 0.05) in the methylated and the non-methylated subpopulations. In patients with moderately vascularized tumors (rCBV 10.73), however, there was no significant effect ofMGMTmethylation (HR = 1.72,p = 0.10, AUC = 0.56). Conclusions Our results indicate the existence of complementary prognostic information provided byMGMTmethylation and rCBV. Perfusion markers could identify a subpopulation of patients who will benefit the most fromMGMTmethylation. Not considering this information may lead to bias in the interpretation of clinical studies.Open Access funding provided by University of Oslo (incl Oslo University Hospital). This study has received funding from MTS4up project (National Plan for Scientific and Technical Research and Innovation 2013-2016, No. DPI2016-80054-R) (JMGG); H2020-SC12016-CNECT Project (No. 727560) (JMGG), H2020-SC1-BHC-20182020 (No. 825750) (JMGG), the European Research Council (ERC) under the European Union's Horizon 2020 (Grant Agreement No. 758657), the South-Eastern Norway Regional Health Authority Grants 2017073 and 2013069, the Research Council of Norway Grants 261984 (KEE). M.A.T was supported by Programa Estatal de Promocion del Talento y su Empleabilidad en I+D+i (DPI2016-80054-R). E.F.G was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement (No. 844646).Fuster García, E.; Lorente Estellés, D.; Álvarez-Torres, MDM.; Juan-Albarracín, J.; Chelebian-Kocharyan, EA.; Rovira, A.; Auger Acosta, C.... (2021). MGMT methylation may benefit overall survival in patients with moderately vascularized glioblastomas. European Radiology. 31(3):1738-1747. https://doi.org/10.1007/s00330-020-07297-41738174731

    Treatment of rats with a self-selected hyperlipidic diet, increases the lipid content of the main adipose tissue sites in a proportion similar to that of the lipids in the rest of organs and tissues

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    Adipose tissue (AT) is distributed as large differentiated masses, and smaller depots covering vessels, and organs, as well as interspersed within them. The differences between types and size of cells makes AT one of the most disperse and complex organs. Lipid storage is partly shared by other tissues such as muscle and liver. We intended to obtain an approximate estimation of the size of lipid reserves stored outside the main fat depots. Both male and female rats were made overweight by 4-weeks feeding of a cafeteria diet. Total lipid content was analyzed in brain, liver, gastrocnemius muscle, four white AT sites: subcutaneous, perigonadal, retroperitoneal and mesenteric, two brown AT sites (interscapular and perirenal) and in a pool of the rest of organs and tissues (after discarding gut contents). Organ lipid content was estimated and tabulated for each individual rat. Food intake was measured daily. There was a surprisingly high proportion of lipid not accounted for by the main macroscopic AT sites, even when brain, liver and BAT main sites were discounted. Muscle contained about 8% of body lipids, liver 1-1.4%, four white AT sites lipid 28-63% of body lipid, and the rest of the body (including muscle) 38-44%. There was a good correlation between AT lipid and body lipid, but lipid in"other organs" was highly correlated too with body lipid. Brain lipid was not. Irrespective of dietary intake, accumulation of body fat was uniform both for the main lipid storage and handling organs: large masses of AT (but also liver, muscle), as well as in the"rest" of tissues. These storage sites, in specialized (adipose) or not-specialized (liver, muscle) tissues reacted in parallel against a hyperlipidic diet challenge. We postulate that body lipid stores are handled and regulated coordinately, with a more centralized and overall mechanisms than usually assumed

    Robust association between vascular habitats and patient prognosis in glioblastoma: an international retrospective multicenter study

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    This is the peer reviewed version of the following article: del Mar Álvarez-Torres, M., Juan-Albarracín, J., Fuster-Garcia, E., Bellvís-Bataller, F., Lorente, D., Reynés, G., Font de Mora, J., Aparici-Robles, F., Botella, C., Muñoz-Langa, J., Faubel, R., Asensio-Cuesta, S., García-Ferrando, G.A., Chelebian, E., Auger, C., Pineda, J., Rovira, A., Oleaga, L., Mollà-Olmos, E., Revert, A.J., Tshibanda, L., Crisi, G., Emblem, K.E., Martin, D., Due-Tønnessen, P., Meling, T.R., Filice, S., Sáez, C. and García-Gómez, J.M. (2020), Robust association between vascular habitats and patient prognosis in glioblastoma: An international multicenter study. J Magn Reson Imaging, 51: 1478-1486, which has been published in final form at https://doi.org/10.1002/jmri.26958. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Background Glioblastoma (GBM) is the most aggressive primary brain tumor, characterized by a heterogeneous and abnormal vascularity. Subtypes of vascular habitats within the tumor and edema can be distinguished: high angiogenic tumor (HAT), low angiogenic tumor (LAT), infiltrated peripheral edema (IPE), and vasogenic peripheral edema (VPE). Purpose To validate the association between hemodynamic markers from vascular habitats and overall survival (OS) in glioblastoma patients, considering the intercenter variability of acquisition protocols. Study Type Multicenter retrospective study. Population In all, 184 glioblastoma patients from seven European centers participating in the NCT03439332 clinical study. Field Strength/Sequence 1.5T (for 54 patients) or 3.0T (for 130 patients). Pregadolinium and postgadolinium-based contrast agent-enhanced T-1-weighted MRI, T-2- and FLAIR T-2-weighted, and dynamic susceptibility contrast (DSC) T-2* perfusion. Assessment We analyzed preoperative MRIs to establish the association between the maximum relative cerebral blood volume (rCBV(max)) at each habitat with OS. Moreover, the stratification capabilities of the markers to divide patients into "vascular" groups were tested. The variability in the markers between individual centers was also assessed. Statistical Tests Uniparametric Cox regression; Kaplan-Meier test; Mann-Whitney test. Results The rCBV(max) derived from the HAT, LAT, and IPE habitats were significantly associated with patient OS (P < 0.05; hazard ratio [HR]: 1.05, 1.11, 1.28, respectively). Moreover, these markers can stratify patients into "moderate-" and "high-vascular" groups (P < 0.05). The Mann-Whitney test did not find significant differences among most of the centers in markers (HAT: P = 0.02-0.685; LAT: P = 0.010-0.769; IPE: P = 0.093-0.939; VPE: P = 0.016-1.000). Data Conclusion The rCBV(max) calculated in HAT, LAT, and IPE habitats have been validated as clinically relevant prognostic biomarkers for glioblastoma patients in the pretreatment stage. This study demonstrates the robustness of the hemodynamic tissue signature (HTS) habitats to assess the GBM vascular heterogeneity and their association with patient prognosis independently of intercenter variability. Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019.This work was partially supported by: MTS4up project (National Plan for Scientific and Technical Research and Innovation 2013-2016, No. DPI2016-80054-R) (to J.M.G.G.); H2020-SC1-2016-CNECT Project (No. 727560) (to J.M.G.G.) and H2020-SC1-BHC-2018-2020 (No. 825750) (to J.M.G.G.); M.A.T was supported by DPI2016-80054-R (Programa Estatal de Promocion del Talento y su Empleabilidad en I + D + i). The data acquisition and curation of the Oslo University Hospital was supported by: the European Research Council (ERC) under the European Union's Horizon 2020 (Grant Agreement No. 758657), the South-Eastern Norway Regional Health Authority Grants 2017073 and 2013069, and the Research Council of Norway Grants 261984 (to K.E.E.). We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan V GPU used for this research. E.F.G. was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 844646. Figure 1 was designed by the Science Artist Elena Poritskaya.Álvarez-Torres, MDM.; Juan-Albarracín, J.; Fuster García, E.; Bellvís-Bataller, F.; Lorente, D.; Reynés, G.; Font De Mora, J.... (2020). Robust association between vascular habitats and patient prognosis in glioblastoma: an international retrospective multicenter study. Journal of Magnetic Resonance Imaging. 51(5):1478-1486. https://doi.org/10.1002/jmri.2695814781486515Louis, D. N., Perry, A., Reifenberger, G., von Deimling, A., Figarella-Branger, D., Cavenee, W. K., … Ellison, D. W. (2016). The 2016 World Health Organization Classification of Tumors of the Central Nervous System: a summary. Acta Neuropathologica, 131(6), 803-820. doi:10.1007/s00401-016-1545-1Gately, L., McLachlan, S., Dowling, A., & Philip, J. (2017). Life beyond a diagnosis of glioblastoma: a systematic review of the literature. Journal of Cancer Survivorship, 11(4), 447-452. doi:10.1007/s11764-017-0602-7Bae, S., Choi, Y. S., Ahn, S. S., Chang, J. H., Kang, S.-G., Kim, E. H., … Lee, S.-K. (2018). Radiomic MRI Phenotyping of Glioblastoma: Improving Survival Prediction. Radiology, 289(3), 797-806. doi:10.1148/radiol.2018180200Akbari, H., Macyszyn, L., Da, X., Wolf, R. L., Bilello, M., Verma, R., … Davatzikos, C. (2014). Pattern Analysis of Dynamic Susceptibility Contrast-enhanced MR Imaging Demonstrates Peritumoral Tissue Heterogeneity. Radiology, 273(2), 502-510. doi:10.1148/radiol.14132458Weis, S. M., & Cheresh, D. A. (2011). Tumor angiogenesis: molecular pathways and therapeutic targets. Nature Medicine, 17(11), 1359-1370. doi:10.1038/nm.2537De Palma, M., Biziato, D., & Petrova, T. V. (2017). Microenvironmental regulation of tumour angiogenesis. Nature Reviews Cancer, 17(8), 457-474. doi:10.1038/nrc.2017.51Jain, R., Poisson, L. M., Gutman, D., Scarpace, L., Hwang, S. N., Holder, C. A., … Flanders, A. (2014). Outcome Prediction in Patients with Glioblastoma by Using Imaging, Clinical, and Genomic Biomarkers: Focus on the Nonenhancing Component of the Tumor. Radiology, 272(2), 484-493. doi:10.1148/radiol.14131691Jensen, R. L., Mumert, M. L., Gillespie, D. L., Kinney, A. Y., Schabel, M. C., & Salzman, K. L. (2013). Preoperative dynamic contrast-enhanced MRI correlates with molecular markers of hypoxia and vascularity in specific areas of intratumoral microenvironment and is predictive of patient outcome. Neuro-Oncology, 16(2), 280-291. doi:10.1093/neuonc/not148Jena, A., Taneja, S., Gambhir, A., Mishra, A. K., D’souza, M. M., Verma, S. M., … Sogani, S. K. (2016). Glioma Recurrence Versus Radiation Necrosis. Clinical Nuclear Medicine, 41(5), e228-e236. doi:10.1097/rlu.0000000000001152Price, S. J., Young, A. M. H., Scotton, W. J., Ching, J., Mohsen, L. A., Boonzaier, N. R., … Larkin, T. J. (2015). Multimodal MRI can identify perfusion and metabolic changes in the invasive margin of glioblastomas. Journal of Magnetic Resonance Imaging, 43(2), 487-494. doi:10.1002/jmri.24996Chang, Y.-C. C., Ackerstaff, E., Tschudi, Y., Jimenez, B., Foltz, W., Fisher, C., … Stoyanova, R. (2017). Delineation of Tumor Habitats based on Dynamic Contrast Enhanced MRI. Scientific Reports, 7(1). doi:10.1038/s41598-017-09932-5Cui, Y., Tha, K. K., Terasaka, S., Yamaguchi, S., Wang, J., Kudo, K., … Li, R. (2016). Prognostic Imaging Biomarkers in Glioblastoma: Development and Independent Validation on the Basis of Multiregion and Quantitative Analysis of MR Images. Radiology, 278(2), 546-553. doi:10.1148/radiol.2015150358Juan-Albarracín, J., Fuster-Garcia, E., Pérez-Girbés, A., Aparici-Robles, F., Alberich-Bayarri, Á., Revert-Ventura, A., … García-Gómez, J. M. (2018). 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Differentiation between vasogenic-edema versus tumor-infiltrative area in patients with glioblastoma during bevacizumab therapy: A longitudinal MRI study. European Journal of Radiology, 83(7), 1250-1256. doi:10.1016/j.ejrad.2014.03.02

    Effect of Sex and Prior Exposure to a Cafeteria Diet on the Distribution of Sex Hormones between Plasma and Blood Cells

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    It is generally assumed that steroid hormones are carried in the blood free and/or bound to plasma proteins. We investigated whether blood cells were also able to bind/carry sex-related hormones: estrone, estradiol, DHEA and testosterone. Wistar male and female rats were fed a cafeteria diet for 30 days, which induced overweight. The rats were fed the standard rat diet for 15 additional days to minimize the immediate effects of excess ingested energy. Controls were always kept on standard diet. After the rats were killed, their blood was used for 1) measuring plasma hormone levels, 2) determining the binding of labeled hormones to washed red blood cells (RBC), 3) incubating whole blood with labeled hormones and determining the distribution of label between plasma and packed cells, discounting the trapped plasma volume, 4) determining free plasma hormone using labeled hormones, both through membrane ultrafiltration and dextran-charcoal removal. The results were computed individually for each rat. Cells retained up to 32% estrone, and down to 10% of testosterone, with marked differences due to sex and diet (the latter only for estrogens, not for DHEA and testosterone). Sex and diet also affected the concentrations of all hormones, with no significant diet effects for estradiol and DHEA, but with considerable interaction between both factors. Binding to RBC was non-specific for all hormones. Estrogen distribution in plasma compartments was affected by sex and diet. In conclusion: a) there is a large non-specific RBC-carried compartment for estrone, estradiol, DHEA and testosterone deeply affected by sex; b) Prior exposure to a cafeteria (hyperlipidic) diet induced hormone distribution changes, affected by sex, which hint at sex-related structural differences in RBC membranes; c) We postulate that the RBC compartment may contribute to maintain free (i.e., fully active) sex hormone levels in a way similar to plasma proteins non-specific binding
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