758 research outputs found
Modeling a solar pressurized volumetric receiver integrated in a parabolic dish: Off-design heat transfers, temperatures, and efficiencies
No full textConcentrated solar power plants are commonly recognized as one of the most attractive options within carbon -free power generation technologies because of their high efficiency and feasible hybridization and/or storage implementation. In this work, a complete heat transfer analysis for an air volumetric receiver coupled to a parabolic dish focused on distributed generation (in the range of kWe) is carried out. It includes most relevant heat losses. Dish collector optical efficiency is computed by means of a ray-tracing software while the thermal performance of the solar receiver is modeled under steady-state conditions using a comprehensive set of equations with a clear physical origin and meaning. Detailed information on the temperatures and heat transfers along the different inner and outer receiver zones are computed with a built from scratch in-house code programmed in Mathematica & REG;. The model considers the main losses from convection, conduction and radiation and through the surrounding insulator. The resulting thermal efficiency mainly depends on the incoming solar irradiance at the glass window, the receiver geometry and the type of materials considered, as well as on the ambient temperature. Explicit numerical results are given at two locations under different meteorological conditions. Optical efficiencies reach values of about 84%. For irradiance values around 800- 900 W/m2, at the receiver outlet, air can reach temperatures of about 1200 K and receiver thermal efficiency is over 80%. It is expected that this model (precise but not too expensive from the computational viewpoint) could help to identify the main efficiency bottlenecks, paving the way for optimization when designing this type of concentrated solar plants through further coupling with a power block, as Brayton or other cycles
Solar volumetric receiver coupled to a parabolic dish: heat transfer and thermal efficiency analysis
No full textDo patients with bipolar disorder and subsyndromal symptoms benefit from functional remediation? A 12-month follow-up study
No full textSanchez-Moreno, J., Bonnín, C., González-Pinto, A., Amann, B.L., Solé, B., Balanzá-Martínez, V., Arango, C., Jimenez, E., Tabarés-Seisdedos, R., Garcia-Portilla, M.P., Ibáñez, A., Crespo, J.M., Ayuso-Mateos, J.L., Vieta, E., Martinez-Aran, A., Torrent, C., Anaya, C., Barbeito, S., Bobes, J., Chiclana, G., Cerrillo, E., Colom, F., Correa, P., Custal, N., Fernández, P., Fernández, M., Fuentes-Durá, I., Galván, G., González-Ortega, I., Isella, S., Landín-Romero, R., Manuel Menchón, J., Merchan-Naranjo, J., Ortiz-Gil, J., Pacchiarotti, I., Reyes, R., Rosa, A.R., Reyes, R., Rapado-Castro, M., Maria Rodao, J., Saiz, P.A., Segura, B., Selva-Vera, G., Saiz-Ruiz, J., Soria, V., Subirá, M., Ugarte, A., Valle, J., Valls, E., Varo, C
Efficacy of Functional Remediation in Bipolar Disorder: A Multicenter Randomized Controlled Study
No full textTorrent, C., Del Mar Bonnin, C., Martínez-Arán, A., Valle, J., Amann, B.L., González-Pinto, A., Crespo, J.M., Ibáñez, A., Garcia-Portilla, M.P., Tabarés-Seisdedos, R., Arango, C., Colom, F., Solé, B., Pacchiarotti, I., Rosa, A.R., Ayuso-Mateos, J.L., Anaya, C., Fernández, P., Landín-Romero, R., Alonso-Lana, S., Ortiz-Gil, J., Segura, B., Barbeito, S., Vega, P., Fernández, M., Ugarte, A., Subirà, M., Cerrillo, E., Custal, N., Menchón, J.M., Saiz-Ruiz, J., Rodao, J.M., Isella, S., Alegría, A., Al-Halabi, S., Bobes, J., Galván, G., Saiz, P.A., Balanzá-Martínez, V., Selva, G., Fuentes-Durá, I., Correa, P., Mayoral, M., Chiclana, G., Merchan-Naranjo, J., Rapado-Castro, M., Salamero, M., Vieta, E
The emotional impact of bullying and cyberbullying on victims: a European crossnational Study
No full textThis study is to analyze the emotional impact on victims of traditional bullying, both direct and indirect forms, and of cyberbullying through mobile phones and the Internet. A sample of 5,862 adolescents from three different countries, Italy (N = 1,964), Spain (N = 1,671), and England (N = 2,227), responded to a questionnaire that asked if they had experience of various forms of bullying, and the consequent emotional impact. The results show that both traditional bullying and cyberbullying have a significant prevalence in the samples. Emotional responses are linked to types of bullying. Analysis of answers identified specific emotional profiles for the different types of bullying and cyberbullying. Direct bullying and cyberbullying via mobile phone showed similar profiles, and also indirect bullying and cyberbullying using the Internet. Similarities and differences between profiles are discussed and some hypotheses are presented to explain the results. In addition, school grade, gender, country, and severity of bullying episodes were related to the specific emotional profiles of each type of bullying
Abstract 5103: The dark cancer kinome - untapped opportunities for the development of novel drugs
No full textAbstract Kinases are firmly established drug targets in cancer. There are currently 44 FDA approved kinase drug and hundreds of compounds are in clinical development. However, less than 10% of the Kinome is currently targeted and a large proportion is considered understudied by the NIH Illuminating the Druggable Genome Program (https://druggablegenome.net/). No small molecule inhibitors are known for these “dark” proteins, yet many may be opportune novel cancer targets.We developed a computational pipeline to identify and prioritize understudied kinases as cancer drug targets. We analyzed the complete set of tumors in The Cancer Genome Atlas (TCGA). For 33 different cancers we performed differential expression analysis and identified 39 dark kinases that exhibit significant upregulation in at least four types. Using co-expression analysis we built functional networks prioritizing drug targets. To identify small molecules that reverse their expression levels, we leveraged transcriptional response signatures obtained from dozens of human cancer cell lines exposed to tens of thousands of small molecules from the Library of Integrated Network-based Cellular Signatures (LINCS). To identify small molecules that directly bind to and inhibit dark kinases, we have have combined an advanced AI (artificial intelligence) model trained on activity data from across the Kinome with structure-based simulations.Using the computational pipeline, we identified the dark Ca2+/Calmodulin dependent kinase PNCK as the most differentially overexpressed kinase in kidney cancer patients. Our analyses have demonstrated statistically significant correlation between PNCK mRNA levels and various clinical and pathological outcomes, including histologic grade, clinical staging and overall survival. We have confirmed high levels of PNCK expression in 5 renal cell carcinoma cell lines (Caki-1, ACHN, 786-O, A704 and A498). Knockdown and overexpression studies have suggested PNCK and the CaMK pathway may contribute to cellular proliferation and cell cycle progression. We have applied our AI-based screening pipeline to a library of >20 million commercially available compounds and confirmed three PNCK inhibiting chemotypes. In summary, using a novel computational pipeline, we have identified and experimentally validated PNCK as a prospective novel drug target in an understudied pathway that is highly upregulated in kidney cancer. We identified first in class small molecules that target this previously dark kinase as prospective starting points for optimization into a clinical candidate. Citation Format: Derek J. Essegian, Rimpi Khurana, Vasileios Stathias, Valery Chavez, Jaime R. Merchan, Stephan Schürer. The dark cancer kinome - untapped opportunities for the development of novel drugs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5103
Factors associated with poor functional outcome in bipolar disorder: Sociodemographic, clinical, and neurocognitive variables
No full textThis work was supported by grants from the Spanish Ministry of Economy, Industry and Competitiveness grant numbers (PI080180, PI08/90825, PI08/90327, PI08/90675, PI08/90224, PI08/90654, PI08/90189, PI08/90916, PI08/90416, PI08/90094, PI11/00637, PI12/00912, PI15/00330, PI15/00283) PN 2008-2011, Instituto de Salud Carlos III, Subdireccion General de Evaluacion y Fomento de la Investigacion, Fondo Europeo de Desarrollo 151 Regional. Union Europea, 'Una manera de hacer Europa', CIBERSAM; and the Comissionat per a Universitats i Recerca del DIUE de la Generalitat de Catalunya (2017 SGR 1365 to the Bipolar Disorders Group).Sanchez-Moreno, J., Bonnin, C.M., González-Pinto, A., Amann, B.L., Solé, B., Balanzá-Martinez, V., Arango, C., Jiménez, E., Tabarés-Seisdedos, R., Garcia-Portilla, M.P., Ibáñez, A., Crespo, J.M., Ayuso-Mateos, J.L., Martinez-Aran, A., Torrent, C., Vieta, E., Alegría, A., Al-Halabi, S., Alonso-Lana, S., Anaya, C., López, P., Bobes, J., Chiclana, G., Cerrillo, E., Correa, P., Custal, N., Fernández, P., García, S., Fuentes-Durá, I., Galván, G., González-Ortega, I., Isella, S., Landín-Romero, R., Menchón, M., Merchan-Naranjo, J., Ortiz-Gil, J., Pacchiarotti, I., Reyes, R., Rapado-Castro, M., Reinares, M., Rodao, M., Saiz, P.A., Segura, B., Selva-Vera, G., Saiz-Ruiz, J., Soria, V., Zorrilla, I., Valle, J., Valls, E., Varo, C., CIBERSAM Functional Remediation Grou
Genetic alterations leading to increases in internal potassium concentrations are detrimental for DNA integrity in Saccharomyces cerevisiae
No full text[EN] We have investigated the effects of alterations in potassium homeostasis on cell cycle progression and genome stability in Saccharomyces cerevisiae. Yeast strains lacking the PPZ1 and PPZ2 phosphatase genes, which aberrantly accumulate potassium, are sensitive to agents causing replicative stress or DNA damage and present a cell cycle delay in the G(1)/S phase. A synthetic slow growth phenotype was identified in a subset of DNA repair mutants upon inhibition of Ppz activity. Moreover, we observe that this slow growth phenotype observed in cdc7ts mutants with reduced Ppz activity is reverted by disrupting the TRK1 potassium transporter gene. As over-expression of a mammalian potassium transporter leads to similar phenotypes, we conclude that these defects can be attributed to potassium accumulation. As we reported previously, internal potassium accumulation activates the Slt2 MAP kinase pathway. We show that the removal of SLT2 in ppz1 ppz2 mutants ameliorates sensitivity to agents causing replication stress and DNA damage, whereas over-activation of the pathway leads to similar cell cycle-related defects. Taken together, these results are consistent with inappropriate potassium accumulation reducing DNA replication efficiency, negatively influencing DNA integrity and leading to the requirement of mismatch repair, the MRX complex, or homologous recombination pathways for normal growth.This work was supported by the Ministry of Education and Science (Madrid) [grant number BFU2005-06388-C04-01/BMC]; the Ministry of Science and Innovation (Madrid) [grant number BFU2008-04188-C03-02/BMC]; and Spanish Ministry of Science and Technology [Ramon y Cajal fellowship to L.Y. and predoctoral fellowship to S.M.]. The authors would like to acknowledge Jose Ramon Murguia for helpful comments and Jose Miguel Mulet, David Quintana, Maria Molina, and Jost Ludwig for providing strains and plasmids.Merchan, SE.; Pedelini, L.; Hueso Lorente, G.; Calzada, A.; Serrano Salom, R.; Yenush, L. (2011). Genetic alterations leading to increases in internal potassium concentrations are detrimental for DNA integrity in Saccharomyces cerevisiae. Genes to Cells. 16(2):152-165. https://doi.org/10.1111/j.1365-2443.2010.01472.xS152165162Arino, J., Ramos, J., & Sychrova, H. (2010). Alkali Metal Cation Transport and Homeostasis in Yeasts. Microbiology and Molecular Biology Reviews, 74(1), 95-120. doi:10.1128/mmbr.00042-09Baetz, K., Moffat, J., Haynes, J., Chang, M., & Andrews, B. (2001). Transcriptional Coregulation by the Cell Integrity Mitogen-Activated Protein Kinase Slt2 and the Cell Cycle Regulator Swi4. Molecular and Cellular Biology, 21(19), 6515-6528. doi:10.1128/mcb.21.19.6515-6528.2001Bell, S. P., & Dutta, A. 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Angiotensin II induces soluble fms-Like tyrosine kinase-1 release via calcineurin signaling pathway in pregnancy
No full textMaternal endothelial dysfunction in preeclampsia is associated with increased soluble fms-like tyrosine kinase-1 (sFlt-1), a circulating antagonist of vascular endothelial growth factor and placental growth factor. Angiotensin II (Ang II) is a potent vasoconstrictor that increases concomitant with sFlt-1 during pregnancy. Therefore, we speculated that Ang II may promote the expression of sFlt-1 in pregnancy. Here we report that infusion of Ang II significantly increases circulating levels of sFlt-1 in pregnant mice, thereby demonstrating that Ang II is a regulator of sFlt-1 secretion in vivo. Furthermore, Ang II stimulated sFlt-1 production in a dose- and time-dependent manner from human villous explants and cultured trophoblasts but not from endothelial cells, suggesting that trophoblasts are the primary source of sFlt-1 during pregnancy. As expected, Ang II-induced sFlt-1 secretion resulted in the inhibition of endothelial cell migration and in vitro tube formation. In vitro and in vivo studies with losartan, small interfering RNA specific for calcineurin and FK506 demonstrated that Ang II-mediated sFlt-1 release was via Ang II type 1 receptor activation and calcineurin signaling, respectively. These findings reveal a previously unrecognized regulatory role for Ang II on sFlt-1 expression in murine and human pregnancy and suggest that elevated sFlt-1 levels in preeclampsia may be caused by a dysregulation of the local renin/angiotensin system
Passive seismic exploration in an urban environment along the projected route of an underground railway
No full textWe utilised the Refraction Microtremors (ReMi) seismic technique to conduct a survey in the city of Malaga in Spain to support a project for the construction of a new subway line in the vicinity of the coast.
The ReMi technique was chosen to carry out the survey because of the expected difficulties of conventional seismic operations in a densely populated urban area with its logistical and administrative restrictions and with a very high level of background noise.
A total of about 1400 m of profiles were collected in two days of field work. The correlation of shear wave maps with the available borehole stratigraphy was generally good. In a few areas, probably because of structural complexity, ReMi interpretation of the data was not definitive. Poor ReMi performance was seen as an indicator of zones of geological complexity requiring either further geophysical investigation or special attention during tunnel excavation.
The ReMi technique proved to be adequate for characterising the shallow subsurface in the study site in terms of geometry and shear wave velocity down to a depth of 5070
meters. The bandwidth andamplitude of the spectrum of the traffic and urban noise were sufficient to generate usable surface waves
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