34 research outputs found

    Properties of galaxies at the faint end of the Hα\alpha luminosity function at z∌0.62z\sim0.62

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    Studies measuring the star formation rate density, luminosity function, and properties of star-forming galaxies are numerous. However, it exists a gap at 0.5<z<0.80.5<z<0.8 in Hα\alpha-based studies. Our main goal is to study the properties of a sample of faint Hα\alpha emitters at z∌0.62z\sim0.62. We focus on their contribution to the faint end of the luminosity function and derived star formation rate density, characterising their morphologies and basic photometric and spectroscopic properties. We use a narrow-band technique in the near-infrared, with a filter centred at 1.06 ÎŒ\mum. The data come from ultra-deep VLT/HAWK-I observations in the GOODS-S field with a total of 31.9 h in the narrow-band filter. We perform a visual classification of the sample and study their morphologies from structural parameters available in CANDELS. Our 28 Hα\alpha-selected sample of faint star-forming galaxies reveals a robust faint-end slope of the luminosity function α=−1.46−0.08+0.16\alpha=-1.46_{-0.08}^{+0.16}. The derived star formation rate density at z∌0.62z\sim0.62 is ρSFR=0.036−0.008+0.012M⊙ yr−1 Mpc−3\rho_\mathrm{SFR} = 0.036_{-0.008}^{+0.012} M_{\odot}~\mathrm{yr^{-1}~Mpc^{-3}}. The sample is mainly composed of disks, but an important contribution of compact galaxies with S\'ersic indexes n∌2n\sim2 display the highest specific star formation rates. The luminosity function at z∌0.62z\sim0.62 from our ultra-deep data points towards a steeper α\alpha when an individual extinction correction for each object is applied. Compact galaxies are low-mass, low-luminosity, and starburst-dominated objects with a light profile in an intermediate stage from early to late types.Comment: Published in Astronomy & Astrophysics. 19 pages, 14 figures. New version includes language edited by the journa

    Recent stellar mass assembly of low-mass star-forming galaxies at redshifts 0.3 < z < 0.9

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    The epoch when low-mass star forming galaxies (LMSFGs) form the bulk of their stellar mass is uncertain. While some models predict an early formation, others favor a delayed scenario until later ages of the universe. We present constraints on the star formation histories (SFHs) of a sample of LMSFGs obtained through the analysis of their spectral energy distributions using a novel approach that (1) consistently combines photometric (broadband) and spectroscopic (equivalent widths of emission lines) data, and (2) uses physically motivated SFHs with non-uniform variations of the star formation rate (SFR) as a function of time. The sample includes 31 spectroscopically confirmed LMSFGs (7.3 < log M*/Msun < 8.0) at 0.3 < z_spec < 0.9 in the Extended-Chandra Deep Field-South field (E-CDF-S). Among them, 24 were selected with photometric stellar mass log M*/Msun < 8.0, 0.3 < z_phot < 1.0, and NB816 < 26 AB mag; the remaining 7 were selected as blue compact dwarfs (BCDs) within the same photometric redshift and magnitude ranges. We also study a secondary sample of 43 more massive spectroscopically confirmed galaxies (8.0 < log M*/Msun < 9.1), selected with the same criteria. The SFRs and stellar masses derived for both samples place our targets on the standard main sequence of star forming galaxies. The median SFH of LMSFGs at intermediate redshifts appears to form 90% of the median stellar mass inferred for the sample in the 0.5-1.8 Gyr immediately preceding the observation. These results suggest a recent stellar mass assembly for LMSFGs, consistent with the cosmological downsizing trends. We find similar median SFH timescales for the more massive secondary sample.Comment: 7 pages, 3 figures, 2 tables; ApJ, in pres

    Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)

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    In this study one seismic section offshore Chiloé Island was analyzed to better define the seismic character of the hydrate-bearing sediments. The velocity analysis was used to estimate the gas-phase concentration and relate it to the geological features. The velocity model allowed us to recognize two important layers that characterize hydrate- and free gas-bearing sediments above and below the BSR respectively: one located above the BSR, characterized by high velocity (1,800-2,200 m/s) and a second one, below the BSR, characterized by low velocity (1,600-1,700 m/s). A weak reflector at about 100 m below the BSR marks the base of the second layer. AVO analysis and offset stack sections confirming that the reflector interpreted as BGR is related to free gas presence in the pore space. The velocity field is affected by lateral variation, showing maximum (above the BSR) and minimum (below the BSR) values in the sector. Here, the highest gas hydrate and free gas concentrations were calculated, obtaining 9.5% and 0.5% of total volume respectively. A variable BSR depth (from 300 to 600 mbsf) can be justified supposing a variable geothermal gradient (from 25 to 45 °C/km)

    Reflexiones en torno a la Justicia restaurativa en el ĂĄmbito del menor infractor

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    Las polĂ­ticas pĂșblicas en materia de justicia restaurativa en justicia de menores: anĂĄlisis comparado entre Comunidades AutĂłnomas / VerĂłnica Viñas Chiappini, Helena Soleto y Marta Villar de Oro (pp. 7-56). -- El abogado defensor del menor ante la justicia restaurativa / LucĂ­a Bielsa Casado (pp. 57-111). -- MediaciĂłn en los delitos cometidos por menores a travĂ©s de las TIC / MarĂ­a del Carmen Borrallo Torres (pp. 113-151). -- Aportaciones al sistema ecuatoriano de justicia restaurativa de menores, desde la perspectiva del Derecho internacional y comparado / Eva MarĂ­a Franco Muñoz (pp. 153-184). -- Una propuesta de integraciĂłn de la justicia restaurativa de menores en China / Yani Xue (pp. 185-225)

    Effectiveness of a training intervention to improve the management of vertigo in primary care: a multicentre cluster-randomised trial, VERTAP

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    Background: Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. While BPPV is best treated with canalicular repositioning manoeuvres, they are not routinely performed in primary care (PC). Methods: To evaluate the effectiveness of blended training (online and face-to-face) on the diagnosis and management of vertigo to improve adherence of family doctors to clinical practice guidelines, we designed a community multicentre cluster-randomised open-label trial with an intervention (IG) and a control (GC) group of 10 primary care teams (PCT) each. Outcome variables will be ICD-10 diagnostic codes (proportion of nonspecific diagnoses such as dizziness and vertigo versus specific diagnoses such as BPPV, vestibular neuritis, and Meniere's disease); number of referrals to ENT or neurology specialists; prescription of antivertigo agents; and duration of sick leave due to vertigo. The baseline comparability of the two study groups will be analysed to ensure homogeneity. A description of all baseline variables will be performed. Student's t-test will be used to evaluate the differences between the groups. Logistic regression multivariate analysis will be performed to study the relationship between baseline variables of professionals and centres with outcome variables. Discussion: With the improvement of the diagnosis and management of vertigo by family doctors after this training, we expect an increase in the proportion of specific diagnoses, a decrease in the prescription of antivertigo agents, a decrease in referrals to ENT or neurology specialists and a reduction in the duration of sick leave due to temporary disability. The blended training will be easily expanded within primary care services, since it is mainly delivered online, with a single face-to-face session to ensure that the manoeuvres have been adequately learned

    A cold seep triggered by a hot ridge subduction

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    The Chile Triple Junction, where the hot active spreading centre of the Chile Rise system subducts beneath the South American plate, offers a unique opportunity to understand the influence of the anomalous thermal regime on an otherwise cold continental margin. Integrated analysis of various geophysical and geological datasets, such as bathymetry, heat flow measured directly by thermal probes and calculated from gas hydrate distribution limits, thermal conductivities, and piston cores, have improved the knowledge about the hydrogeological system. In addition, rock dredging has evidenced the volcanism associated with ridge subduction. Here, we argue that the localized high heat flow over the toe of the accretionary prism results from fluid advection promoted by pressure-driven discharge (i.e., dewatering/discharge caused by horizontal compression of accreted sediments) as reported previously. However, by computing the new heat flow values with legacy data in the study area, we raise the assumption that these anomalous heat flow values are also promoted by the eastern flank of the currently subducting Chile Rise. Part of the rift axis is located just below the toe of the wedge, where active deformation and vigorous fluid advection are most intense, enhanced by the proximity of the young volcanic chain. Our results provide valuable information to current and future studies related to hydrothermal circulation, seismicity, volcanism, gas hydrate stability, and fluid venting in this natural laboratory

    Big dynorphin is a neuroprotector scaffold against amyloid ÎČ-peptide aggregation and cell toxicity

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    Amyloid ÎČ-peptide (AÎČ) misfolding into ÎČ-sheet structures triggers neurotoxicity inducing Alzheimer's disease (AD). Molecules able to reduce or to impair AÎČ aggregation are highly relevant as possible AD treatments since they should protect against AÎČ neurotoxicity. We have studied the effects of the interaction of dynorphins, a family of opioid neuropeptides, with AÎČ40 the most abundant species of AÎČ. Biophysical measurements indicate that AÎČ40 interacts with Big Dynorphin (BigDyn), lowering the amount of hydrophobic aggregates, and slowing down the aggregation kinetics. As expected, we found that BigDyn protects against AÎČ40 aggregates when studied in human neuroblastoma cells by cell survival assays. The cross-interaction between BigDyn and AÎČ40 provides insight into the mechanism of amyloid pathophysiology and may open up new therapy possibilities.The authors would like to thank Mr. Jordi Pujols Pujol for skillful technical assistance in RP-HPLC experiments, and Mr. Mateo Calle VelĂĄsquez for skillful assistance in the docking process.Peer reviewe

    PromociĂłn de la salud y entornos saludables

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    A forestar forestalAplicaci&oacute;n de un programa educativo participativo en salud&nbsp; bucal a una comunidad de adultos mayoresBiblioteca m&oacute;vil y su implementaci&oacute;n en el hospital Padre HurtadoConsumo de riesgo de alcohol en Chile: una propuesta innovadora de intervenci&oacute;nDise&ntilde;o de un programa interactivo de promoci&oacute;n de la salud vocal para NB1Encuentro formativo en promoci&oacute;n de salud y gesti&oacute;n de entornos saludables para TenoExperiencia docente: programa intersectorial de promoci&oacute;n/prevenci&oacute;n en preescolares de comunas vulnerables, Regi&oacute;n MetropolitanaFiltrado glomerular, m&eacute;todo preventivo aparici&oacute;n de fibrosis sist&eacute;mica nefrog&eacute;nica por gadolinio en examen de RMImplementaci&oacute;n de consejer&iacute;as en vida sana en APS, Regi&oacute;n de los R&iacute;osMedicina preventiva en feria libre de la poblaci&oacute;n San Gregorio: Cecof San Gregorio, Contagiando SaludMetodolog&iacute;a innovadora en la ense&ntilde;anza de una ectoparasitosisPrevenci&oacute;n de accidentes por mon&oacute;xido de carbono en edificios, Providencia 2002-2009Programa de promoci&oacute;n y prevenci&oacute;n en salud bucal para preescolaresPromoviendo h&aacute;bitos saludables en los vecinos de Re&ntilde;aca Alto, Vi&ntilde;a del Mar, 2009Rol de la capacitaci&oacute;n en la implementaci&oacute;n de acciones para la prevenci&oacute;n de la obesidadSatisfacci&oacute;n usuaria en el Cesfam Natales a un a&ntilde;o de su funcionamientoTres estrategias publicitarias y de comunicaci&oacute;n aplicadas al consumo de alcohol de bajo riesgoTropa de la salud: uso de los medios como forma de promover la salu

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    EstuPlan: Methodology for the development of creativity in the resolution of scientific and social problems

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    [EN] Creative thinking is necessary to generate novel ideas and solve problems. "EstuPlan" is a methodology in which knowledge and creativity converge for the resolution of scientific problems with social projection. It is a training programme that integrates teachers, laboratory technicians and PhD students, master and undergraduate students which form working groups for the development of projects. Projects have a broad and essential scope and projection in terms of environmental problems, sustainable use of natural resources, food, health, biotechnology or biomedicine. The results show the success of this significant learning methodology using tools to develop creativity in responding to scientific and social demand for problem-solving to transfer academic knowledge to different professional environments. Bioplastics, Second Life of Coffee, LimBio, Algae oils, Ecomers, Caring for the life of your crop and Hate to Deforestate are currently being developed.Astudillo CalderĂłn, S.; De DĂ­ez De La Torre, L.; GarcĂ­a Companys, M.; Ortega PĂ©rez, N.; RodrĂ­guez MartĂ­nez, V.; Alzahrani, S.; Alonso Valenzuela, R.... (2019). EstuPlan: Methodology for the development of creativity in the resolution of scientific and social problems. En HEAD'19. 5th International Conference on Higher Education Advances. Editorial Universitat PolitĂšcnica de ValĂšncia. 711-717. https://doi.org/10.4995/HEAD19.2019.9205OCS71171
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