60 research outputs found

    Variabilidad estacional de la productividad primaria y su relación con la estratificación vertical en la Bahía de la Paz, B. C. S.

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    Primary productivity (pp) during October of 1996, March, April, May, June, July, September, November of 1997 and January of 1998, was estimated via natural fluorescence in La Paz bay. Simultaneously to pp vertical temperatura profiles (CTD) were registered to determine the structure of the water column, which was calculated by using the stratification index (?) from 0 to 100 m depth. The highest average values in pp (16 mg C m-3 h-1) were observed during the spring and the minimum values of ? (50 J m-3)  corresponded to a almost homogeneous water column. In contrast, to other seasons (summer and autumn), the pp fell to minimum values (2 to 5 mg C m-3 h-1), while ? increased significantly (249 and 347 J m-3). The results indicated a lineal dependence between pp and water column mixture (r2 = 0.62, p <0.05) during the summer months. Periods with high stratification seem to inhibit the fertilization on the surface layer, while the well mixed water column facilitate the fertilization process. Therefore, it is evident that the water column stratification in La Paz bay plays an important role mechanism that controls the pp and partially explains the seasonal variability.Se estimó la productividad primaria (pp) vía fluorescencia natural en la bahía de La Paz durante octubre de 1996, marzo, abril, mayo, junio, julio, septiembre, noviembre de 1997, y enero de 1998. Simultáneamente a los registros de pp se realizaron perfiles verticales de temperatura (CTD) para determinar la estructura de la columna de agua, y de los cuales se estimó el índice de estratificación (?) de 0 a 100 m de profundidad. Durante primavera se observaron los valores promedio más altos de pp (16 mg C m-3 h-1) y valores bajos de ? (50 J m-3) que corresponden a una columna de agua casi homogénea. En contraste, en las subsecuentes estaciones (verano y otoño), la pp decreció a valores mínimos (2 y 5 mg C m-3 h-1), mientras que ? se incrementó significativamente (249 y 347 J m-3). Los resultados indican que existe una dependencia lineal de la pp y la mezcla en la columna de agua (r2 = 0.62, p<0.05) durante los meses de verano. Periodos con una alta estratificación tienden posiblemente a inhibir la fertilización de la capa superficial, mientras que una columna de agua bien mezclada facilita el proceso de fertilización. Por lo tanto, es evidente que en la Bahía de La Paz la estratificación asume un papel importante como mecanismo que controla la pp y explica parcialmente la variabilidad estacional observada en la bahía

    The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and T e-based literature data

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    Astronomy and Astrophysics 559 (2013): A114 reproduced with permission from Astronomy and AstrophysicsThe use of integral field spectroscopy is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies, both locally and at high redshift. Many studies have used these fluxes to derive the gas-phase metallicity of the galaxies by applying the so-called strong-line methods. However, the metallicity indicators that these datasets use were empirically calibrated using few direct abundance data points (Te-based measurements). Furthermore, a precise determination of the prediction intervals of these indicators is commonly lacking in these calibrations. Such limitations might lead to systematic errors in determining the gas-phase metallicity, especially at high redshift, which might have a strong impact on our understanding of the chemical evolution of the Universe. The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using newdirect abundance measurements. We pay special attention to (1) the expected uncertainty of these calibrations as a function of the index value or abundance derived and (2) the presence of possible systematic offsets. This is possible thanks to the analysis of the most ambitious compilation of Te-based H ii regions to date. This new dataset compiles the Te-based abundances of 603 H ii regions extracted from the literature but also includes new measurements from the CALIFA survey. Besides providing new and improved empirical calibrations for the gas abundance, we also present a comparison between our revisited calibrations with a total of 3423 additional CALIFA H ii complexes with abundances derived using the ONS calibration from the literature. The combined analysis of T e-based and ONS abundances allows us to derive their most accurate calibration to date for both the O3N2 and N2 single-ratio indicators, in terms of all statistical significance, quality, and coverage of the parameters space. In particular, we infer that these indicators show shallower abundance dependencies and statistically significant offsets compared to others'. The O3N2 and N2 indicators can be empirically applied to derive oxygen abundances calibrations from either direct abundance determinations with random errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a large amount of data), reaching an average precision of 0.08 and 0.09 dex (random) and 0.02 and 0.08 dex (systematic; compared to the direct estimations), respectivelyR.A. Marino is funded by the Spanish program of International Campus of Excellence Moncloa (CEI). D. Mast thank the Plan Nacional de Investigación y Desarrollo funding programs, AYA2012-31935 of the Spanish Ministerio de Economía y Competitividad, for the support given to this project. S.F.S thanks the the Ramón y Cajal project RyC-2011-07590 of the spanish Ministerio de Economía y Competitividad, for the support giving to this project. F.F.R.O. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the program Estancias Postdoctorales y Sabáticas al Extranjero para la Consolidación de Grupos de Investigación, 2010-2012. We acknowledge financial support for the ESTALLIDOS collaboration by the Spanish Ministerio de Ciencia e Innovación under grant AYA2010- 21887-C04-03. BG-L also acknowledges support from the Spanish Ministerio de Economía y Competitividad (MINECO) under grant AYA2012- 39408-C02-02. J.F.-B. acknowledges financial support from the Ramón y Cajal Program and grant AYA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO), as well as to the DAGAL network from the People’s Program (Marie Curie Actions) of the European Union’s Seventh Framework Program FP7/2007-2013/ under REA grant agreement number PITN-GA-2011-289313. CK has been funded by project AYA2010-21887 from the Spanish PNAYA. P.P. acknowledges support by the Fundação para a Ciência e a Tecnologia (FCT) under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE). R.M.G.D. and R.G.B. also acknowledge support from the Spanish Ministerio de Economía y Competitividad (MINECO) under grant AyA2010-15081. V.S., L.G., and A.M.M. acknowledge financial support from the Fundação para a Ciência e a Tecnologia (FCT) under program Ciência 2008 and the research grant PTDC/CTE-AST/112582/200

    Neuroprotective properties of queen bee acid by autophagy induction

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    Autophagy is a conserved intracellular catabolic pathway that removes cytoplasmic components to contribute to neuronal homeostasis. Accumulating evidence has increasingly shown that the induction of autophagy improves neuronal health and extends longevity in several animal models. Therefore, there is a great interest in the identification of effective autophagy enhancers with potential nutraceutical or pharmaceutical properties to ameliorate age-related diseases, such as neurodegenerative disorders, and/or promote longevity. Queen bee acid (QBA, 10-hydroxy-2-decenoic acid) is the major fatty acid component of, and is found exclusively in, royal jelly, which has beneficial properties for human health. It is reported that QBA has antitumor, anti-inflammatory, and antibacterial activities and promotes neurogenesis and neuronal health; however, the mechanism by which QBA exerts these effects has not been fully elucidated. The present study investigated the role of the autophagic process in the protective effect of QBA. We found that QBA is a novel autophagy inducer that triggers autophagy in various neuronal cell lines and mouse and fly models. The beclin-1 (BECN1) and mTOR pathways participate in the regulation of QBA-induced autophagy. Moreover, our results showed that QBA stimulates sirtuin 1 (SIRT1), which promotes autophagy by the deacetylation of critical ATG proteins. Finally, QBA-mediated autophagy promotes neuroprotection in Parkinson’s disease in vitro and in a mouse model and extends the lifespan of Drosophila melanogaster. This study provides detailed evidences showing that autophagy induction plays a critical role in the beneficial health effects of QBA.This research was supported by a grant (IB18048) from Junta de Extremadura, Spain, and a grant (RTI2018-099259-A-I00) from Ministerio de Ciencia e Innovación, Spain. This work was also partially supported by “Fondo Europeo de Desarrollo Regional” (FEDER) from the European Union. Part of the equipment employed in this work has been funded by Generalitat Valeciana and co-financed with ERDF funds (OP EDRF of Comunitat Valenciana 2014-2020). G.M-C is supported by University of Extremadura (ONCE Foundation). M.P-B is a recipient of a fellowship from the “Plan Propio de Iniciación a la Investigación, Desarrollo Tecnológico e Innovación (University of Extremadura).” S.M.S.Y-D is supported by CIBERNED. E.U-C was supported by an FPU predoctoral fellowship FPU16/00684 from Ministerio de Educación, Cultura y Deporte. A.B. was supported by a postdoctoral fellowship (APOSTD2017/077). M.S.A. was supported by a predoctoral fellowship (ACIF/2018/071) both from the Conselleria d’Educació, Investigació, Cultura i Esport (Generalitat Valenciana). E.A-C was supported by a grant (IB18048) from Junta de Extremadura, Spain. S.C-C was supported by an FPU predoctoral fellowship FPU19/04435 from Ministerio de Educación, Cultura y Deporte. J.M.B-S. P was funded by the “Ramón y Cajal” program (RYC-2018-025099). J.M.F. received research support from the Instituto de Salud Carlos III, CIBERNED (CB06/05/004). M.N-S was funded by the “Ramon y Cajal” Program (RYC-2016-20883) Spain

    México y Jalisco en la coyuntura : segundo semestre de 1998

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    Análisis de coyuntura sobre los principales sucesos del segundo semestre de 1998 en Jalisco y México. El caso del FOBAPROA, la seguridad pública, los derechos humanos, las elecciones efectuadas en el período y las estrategias de los partidos políticos en Jalisco son analizados por autores diversos. Se estudia también el caso de la industria electrónica en Guadalajara y la relación de los grupos de la sociedad civil con el gobierno.ITESO, A.C

    Star formation in the local Universe from the CALIFA sample: I. Calibrating the SFR using integral field spectroscopy data

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    The star formation rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires the use of low spatial resolution far-infrared data. Recombination line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrowband imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral field spectroscopy (IFS) is clearly the way to overcome this kind of limitation. Aims. We obtain integrated Hα, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005 <z< 0.03 using single-band and hybrid tracers. We aim to determine whether the extinction-corrected Hα luminosities provide a good measure of the SFR and to shed light on the origin of the discrepancies between tracers. Updated calibrations referred to Hα are provided. The well-defined selection criteria and large statistics allow us to carry out this analysis globally and split by properties, including stellar mass and morphological type. Methods. We derive integrated, extinction-corrected Hα fluxes from CALIFA, UV surface and asymptotic photometry from GALEX and integrated WISE 22 μm and IRAS fluxes. Results. We find that the extinction-corrected Hα luminosity agrees with the hybrid updated SFR estimators based on either UV or Hα plus IR luminosity over the full range of SFRs (0.03-20 M yr). The coefficient that weights the amount of energy produced by newly-born stars that is reprocessed by dust on the hybrid tracers, a, shows a large dispersion. However, this coefficient does not became increasingly small at high attenuations, as expected if significant highly-obscured Hα emission were missed, i.e., after a Balmer decrement-based attenuation correction is applied. Lenticulars, early-type spirals, and type-2 AGN host galaxies show smaller coefficients because of the contribution of optical photons and AGN to dust heating. Conclusions. In the local Universe, the Hα luminosity derived from IFS observations can be used to measure SFR, at least in statistically-significant, optically-selected galaxy samples, once stellar continuum absorption and dust attenuation effects are accounted for. The analysis of the SFR calibrations by galaxies properties could potentially be used by other works to study the impact of different selection criteria in the SFR values derived, and to disentangle selection effects from other physically motivated differences, such as environmental or evolutionary effects.The CALIFA collaboration also thanks the CAHA staff for the dedication to this project. C.C.-T. thanks the support of the Spanish Ministerio de Educacion, Cultura y Deporte by means of the FPU fellowship program. The authors also thank the support from the Plan Nacional de Investigacion y Desarrollo funding programs, AYA2012-30717 and AyA2013-46724P, of Spanish Ministerio de Economia y Competitividad (MINECO). P.G.P.-G. acknowledges support from the AYA2012-30717 and AYA2012-31277. J.I.P. acknowledges financial support from the Spanish MINECO under grant AYA2010-21887-C04-01 and from Junta de Andalucia Excellence Project PEX2011-FQM7058. R.A.M. is funded by the Spanish program of International Campus of Excellence Moncloa (CEI). M.A.P.T. acknowledges support from the Spanish MINECO through grant AYA2012-38491-C02-02. A.d.O. acknowledge financial support from the Spanish grant AYA2013-42227-P. Support for L.G. is provided by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. L.G. acknowledges support by CONICYT through FONDECYT grant 3140566. J.M.G. acknowledges support from the Fundacao para a Ciencia e a Tecnologia (FCT) through the Fellowship SFRH/BPD/66958/2009 from FCT (Portugal) and POPH/FSE (EC) by FEDER funding through the program Programa Operacional de Factores de Competitividade (COMPETE). J.M.G. also acknowledges support by FCT under project FCOMP-01-0124-FEDER- 029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE).Peer Reviewe

    México y Jalisco en la coyuntura : primer semestre de 1998

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    Análisis de coyuntura sobre los principales sucesos del primer semestre de 1997 en Jalisco, a nivel político, económico y social: la situación en el estado de los tres principales partidos políticos (PAN, PRI y PRD), la cuestión laboral, los derechos humanos y el problema de abastecimiento de agua en la zona metropolitana de Guadalajara.ITESO, A.C

    Neuroaxial anesthesia caused paraplegia: a case report

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    Patients who undergo; anesthesia, neuraxial analgesia, or some type of neuraxial blockage are exposed to multiple complications. 33-year-old male patient, suffers a femur fracture with a long oblique trace causing pain and functional limitation for movements. Surgical resolution is determined using neuraxial block at L2-L3 level, and intravenous sedation. During his postoperative follow-up, a decrease in strength was confirmed in the lower limbs with 0/5 on the Daniels scale, 100% sensitivity without sphincter control, steroids were prescribed along with magnetic resonance imaging and a neurosurgical evaluation was requested. The MRI shows bulging of the fibrous annulus that obliterates the epidural fat and makes contact with the thecal sac in the L5-S1 intervertebral disc level. The neurosurgery service prescribes rehabilitation sessions at home, electrostimulation and neuropathic medications. Patient was discharged with rehabilitation sessions at home and medical treatment. In his last consultation, an evaluation from the psychiatry department was requested for ideas of disability, hopelessness, fantasies of death without a suicide plan related to limitations and loss of functionality. Patient does not return to external follow-up, cannot be located

    Chronic venous insufficiency: a review

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    Chronic venous insufficiency (CVI) comprises a complete spectrum of morphological and functional abnormalities of the venous system1 including any long-term functional and morphological alteration. CVI accounts for several abnormalities of the venous system. It is a highly prevalent disease that causes serious economic consequences, a decrease in the quality of life and can lead to serious complications. An exhaustive review was performed with the available literature, using the PubMed, ScienceDirect, Scopus and Cochrane databases from 2004 to 2021. The search criteria were formulated to identify reports related to chronic venous insufficiency. The pathophysiology of chronic venous insufficiency begins with chronic venous hypertension and the dilation of the vessel, this leads to a series of pathological changes in the venous wall and surrounding tissues, in advanced stages of CVI, skin lesions are associated with an increased proliferation of skin capillaries and microcirculatory abnormalities that may be the result of an altered level of factors responsible for the angiogenic response, such as vascular endothelial growth factor (VEGF), fibroblast growth factor 2 (FGF2) and angiostatin. In this review, updates on pathophysiology, clinic, diagnosis, classification and treatment of this disease are analyzed, with special emphasis on therapeutic options. Chronic venous insufficiency is a disease that affects the patient at several levels, mainly diminishing his/her quality of life. Currently there are various treatments ranging from habit modifications, pharmacological, to endovenous and surgical treatment.

    Obtention of viable cell suspensions from breast cancer tumor biopsies for 3D chromatin conformation and single-cell transcriptome analysis

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    Molecular and cellular characterization of tumors is essential due to the complex and heterogeneous nature of cancer. In recent decades, many bioinformatic tools and experimental techniques have been developed to achieve personalized characterization of tumors. However, sample handling continues to be a major challenge as limitations such as prior treatments before sample acquisition, the amount of tissue obtained, transportation, or the inability to process fresh samples pose a hurdle for experimental strategies that require viable cell suspensions. Here, we present an optimized protocol that allows the recovery of highly viable cell suspensions from breast cancer primary tumor biopsies. Using these cell suspensions we have successfully characterized genome architecture through Hi-C. Also, we have evaluated single-cell gene expression and the tumor cellular microenvironment through single-cell RNAseq. Both technologies are key in the detailed and personalized molecular characterization of tumor samples. The protocol described here is a cost-effective alternative to obtain viable cell suspensions from biopsies simply and efficiently
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