3,886 research outputs found

    Artificial recharge by means of careo channels versus natural aquifer recharge in a semi-arid, high-mountain watershed (Sierra Nevada, Spain)

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    This research was undertaken as part of the project "Impact, monitoring and assessment of global and climate change on water resources in high-mountain National Parks (CCPM) ", with reference number CANOA-51.3.00.43.00 and funded by Organismo Autonomo Parques Nacionales from the Ministerio para la Transicion Ecologica y el Reto Demografico. The authors thank the Ibero-American Science and Technology for Devel-opment Programme (CYTED) for its financial support to the network "Wa-ter Sowing and Harvesting in Protected Natural Areas" (419RT0577) . This work is a contribution to the Research Group RNM-126 of the Junta de Andalucia. Special thanks goes to the irrigation community in Berchules and the Sierra Nevada National Park for their collaboration. We also appre-ciate the support of AEMET and REDIAM, who provided meteorological and hydrological data. The authors would also like to thank the anonymous reviewers for their constructive comments and suggestions which led to a substantial improvement of the paper.The acequias de careo are ancestral water channels excavated during the early Al-Andalus period (8th–10th centuries), which are used to recharge aquifers in the watersheds of the Sierra Nevada mountain range (Southeastern Spain). The water channels are maintained by local communities, and their main function is collecting snowmelt, but also runoff from rainfall fromthe headwaters of river basins and distributing it throughout the upper parts of the slopes. Thismethod of aquifer artificial recharge extends the availability of water resources in the lowlands of the river basins during the dry season when there is almost no precipitation and water demand is higher. This study investigates the contribution of the careo channels in the watershed of Bérchules concerning the total aquifer recharge during the 2014–2015 hydrological year. Several channels were gauged, and the runoff data were compared with those obtained from a semi-distributed hydrological model applied to the same hydrological basin. The natural infiltration of meteoric waters accounted for 52%of the total recharge, while the remaining 48% corresponded to water transported and infiltrated by the careo channels. In other words, the careo recharge system enhances by 92% the natural recharge to the aquifer. Our results demonstrate the importance of this ancestral and efficient channel system for recharging slope aquifers developed in hard rocks. The acequias de careo are nature-based solutions for increasing water resources availability that have contributed to a prosperous life in the Sierra Nevada. Its long history (>1200 years) suggests that the system has remarkable resilience properties, which have allowed adaptation and permance for centuries in drastically changing climatic and socioeconomic conditions. This recharge system could also be applied to—or inspire similar adaptation measures in— semi-arid mountain areas around the world where it may help in mitigating climate change effects.Organismo Autonomo Parques Nacionales CANOA-51.3.00.43.00Ibero-American Science and Technology for Devel-opment Programme (CYTED) 419RT0577 RNM-126Junta de Andaluci

    A Meiotic Checkpoint Alters Repair Partner Bias to Permit Inter-sister Repair of Persistent DSBs

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    Accurate meiotic chromosome segregation critically depends on the formation of inter-homolog crossovers initiated by double-strand breaks (DSBs). Inaccuracies in this process can drive aneuploidy and developmental defects, but how meiotic cells are protected from unscheduled DNA breaks remains unexplored. Here we define a checkpoint response to persistent meiotic DSBs in C. elegans that phosphorylates the synaptonemal complex (SC) to switch repair partner from the homolog to the sister chromatid. A key target of this response is the core SC component SYP-1, which is phosphorylated in response to ionizing radiation (IR) or unrepaired meiotic DSBs. Failure to phosphorylate (syp-16A) or dephosphorylate (syp-16D) SYP-1 in response to DNA damage results in chromosome non-dysjunction, hyper-sensitivity to IR-induced DSBs, and synthetic lethality with loss of brc-1BRCA1. Since BRC-1 is required for inter-sister repair, these observations reveal that checkpoint-dependent SYP-1 phosphorylation safeguards the germline against persistent meiotic DSBs by channelling repair to the sister chromatid.Cancer Research UK FC0010048UK Medical Research Council FC0010048Wellcome Trust FC0010048Ministerio de Economía y Competitividad BFU2016-75058-PEuropean Research Council ERC2014 AdG669898 TARLOO

    Modeling the effect of the electrode potential in SERS by electronic structure calculations.

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    Surface Enhanced Raman Spectroscopy (SERS), due to the ability of greatly intensify the weak Raman signal of molecules adsorbed to metal surfaces, has proven to be a very useful tool to investigate changes in the electronic structure of metal-molecule surface complex. A deep knowledge of the electronic structure of these metal-molecule hybrid systems is key in electrochemistry, catalysis, plasmonics, molecular electronics, and in the development of selective and ultra-sensitive analytical sensors. The origin of this huge enhancement in SERS is due to two contributions: the electromagnetic (EM), related to surface plasmons, and the chemical mechanism, due to resonant charge transfer (CT) process between the adsorbate and the metal (CTSERS). Unfortunately, the SERS implies very complex phenomena where the molecule and the metal nanoparticle are involved. This fact makes challenging to build realistic theoretical models that take into account both the metal and the molecule at quantum level. We propose a methodology, based on DFT and ab initio electronic calculations, to simulate the effect of the electrode potential on the absorption, on the charge transfer states energies, and on the electronic excitations in metal-molecule hybrid systems from a microscopic point of view. This methodology consists on the prediction of Raman intensities from ab initio calculations of the geometries or the energy gradients at the excited states Franck-Condon point, bringing the possibility to predict the intensities in CTSERS as well as in resonance Raman without the need to know the excited state geometries, not always feasible to compute. The microscopic model adopted to mimic the effect of the interphase electric potential consist in a molecule adsorbed to a linear silver cluster [Agn-Adsorbate]q, were n is the number of silver atoms, and the total charge of the system (q) is zero for n=2 and q=±1 for n=1, 3 and 7.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    The global response regulator RegR controls expression of denitrification genes in Bradyrhizobium japonicum

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    Bradyrhizobium japonicum RegSR regulatory proteins belong to the family of two-component regulatory systems, and orthologs are present in many Proteobacteria where they globally control gene expression mostly in a redox-responsive manner. In this work, we have performed a transcriptional profiling of wild-type and regR mutant cells grown under anoxic denitrifying conditions. The comparative analyses of wild-type and regR strains revealed that almost 620 genes induced in the wild type under denitrifying conditions were regulated (directly or indirectly) by RegR, pointing out the important role of this protein as a global regulator of denitrification. Genes controlled by RegR included nor and nos structural genes encoding nitric oxide and nitrous oxide reductase, respectively, genes encoding electron transport proteins such as cycA (blr7544) or cy 2 (bll2388), and genes involved in nitric oxide detoxification (blr2806-09) and copper homeostasis ( copCAB ), as well as two regulatory genes (bll3466, bll4130). Purified RegR interacted with the promoters of norC (blr3214), nosR (blr0314), a fixK -like gene (bll3466), and bll4130, which encodes a LysR-type regulator. By using fluorescently labeled oligonucleotide extension (FLOE), we were able to identify two transcriptional start sites located at about 35 (P1) and 22 (P2) bp upstream of the putative translational start codon of norC . P1 matched with the previously mapped 5 9 end of norC mRNA which we demonstrate in this work to be under FixK 2 control. P2 is a start site modulated by RegR and specific for anoxic conditions. Moreover, qRT-PCR experiments, expression studies with a norC-lacZ fusion, and heme c -staining analyses revealed that anoxia and nitrate are required for RegR-dependent induction of nor genes, and that this control is independent of the sensor protein Reg

    Relaxation Dynamics of Pseudomonas aeruginosa Re^I(C)O_3(α-diimine)(HisX)^+ (X=83, 107, 109, 124, 126)Cu-^(II) Azurins

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    Photoinduced relaxation processes of five structurally characterized Pseudomonas aeruginosa Re^I(CO)_3(α-diimine)(HisX) (X = 83, 107, 109, 124, 126)Cu^(II) azurins have been investigated by time-resolved (ps−ns) IR spectroscopy and emission spectroscopy. Crystal structures reveal the presence of Re-azurin dimers and trimers that in two cases (X = 107, 124) involve van der Waals interactions between interdigitated diimine aromatic rings. Time-dependent emission anisotropy measurements confirm that the proteins aggregate in mM solutions (D2O, KPi buffer, pD = 7.1). Excited-state DFT calculations show that extensive charge redistribution in the ReI(CO)_3 → diimine ^3MLCT state occurs: excitation of this ^3MLCT state triggers several relaxation processes in Re-azurins whose kinetics strongly depend on the location of the metallolabel on the protein surface. Relaxation is manifested by dynamic blue shifts of excited-state ν(CO) IR bands that occur with triexponential kinetics: intramolecular vibrational redistribution together with vibrational and solvent relaxation give rise to subps, 2, and 8−20 ps components, while the ~10^2 ps kinetics are attributed to displacement (reorientation) of the Re^I(CO)_3(phen)(im) unit relative to the peptide chain, which optimizes Coulombic interactions of the Re^I excited-state electron density with solvated peptide groups. Evidence also suggests that additional segmental movements of Re-bearing β-strands occur without perturbing the reaction field or interactions with the peptide. Our work demonstrates that time-resolved IR spectroscopy and emission anisotropy of Re^I carbonyl−diimine complexes are powerful probes of molecular dynamics at or around the surfaces of proteins and protein−protein interfacial regions

    Justification of interpersonal aggression in Hong Kong and Spain

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    This study reports the degrees of approval for different aggressive acts in a number of instrumental and emotional situations. A nationally-adapted version of the Lagerspetz and Westman questionnaire [1] was administered to 332 university students of both sexes in Spain and Hong Kong. Respondents had to indicate levels of justification of several aggressive acts of different quality and intensity in the context of different social justifications. Our results replicated the general findings of previous research in other cultures: in both samples, more drastic forms of aggression (e.g., killing, torture) were less accepted than non-dangerous forms of such behavior (e.g., hindering, being ironic); aggressive acts more socially justified (in terms of protection of self or other) were clearly more accepted than others with no such justification (problems of communication); and instrumental-motivated aggression was higher justified than emotional-motivated aggression. Some differences in the level of acceptance according to the sex of the participants were found: women were more prone to a higher acceptance of acts and situations more related to emotion. Although both sexes justified aggression in a higher degree for instrumentally motivated situations than for emotional ones, males showed a higher acceptance than females for instrumental situations and a lower one than females for emotional ones. There were also some minor culturally bound differences in these attitudes: Spaniards accepted less than HK students aggression in emotional situations, specially for the cases of punishment and lack of communication, but more emotional acts, such as rage and shouting. Thus, patterns of moral approval of various kinds of aggressive acts are in a large part common to both cultures. Findings also confirmed a two-factor solution and the respective predictive power of justifications for aggression in instrumental vs. emotional motivated situations. The reliability and validity of this brief self-report have been further established by the present study, paving the way for future studies to measure instrumental and emotional aggression

    The aryl hydrocarbon receptor ligand FICZ improves left ventricular remodeling and cardiac function at the onset of pressure overload-Induced heart failure in mice

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    Adverse ventricular remodeling is the heart’s response to damaging stimuli and is linked to heart failure and poor prognosis. Formyl-indolo [3,2-b] carbazole (FICZ) is an endogenous ligand for the aryl hydrocarbon receptor (AhR), through which it exerts pleiotropic effects including protection against inflammation, fibrosis, and oxidative stress. We evaluated the effect of AhR activation by FICZ on the adverse ventricular remodeling that occurs in the early phase of pressure overload in the murine heart induced by transverse aortic constriction (TAC). Cardiac structure and function were evaluated by cardiac magnetic resonance imaging (CMRI) before and 3 days after Sham or TAC surgery in mice treated with FICZ or with vehicle, and cardiac tissue was used for biochemical studies. CMRI analysis revealed that FICZ improved cardiac function and attenuated cardiac hypertrophy. These beneficial effects involved the inhibition of the hypertrophic calcineurin/NFAT pathway, transcriptional reduction in pro-fibrotic genes, and antioxidant effects mediated by the NRF2/NQO1 pathway. Overall, our findings provide new insight into the role of cardiac AhR signaling in the injured heart.This research was supported by Grants SAF2017-84777-R, funded by the Ministry of Economy and Competitiveness (MINECO) of Spain, PID2020-113238RB-I00 funded by the Ministry of Science and Innovation (MCIN)/AEI/ 10.13039/501100011033 of Spain and the “European Union Next GenerationEU/PRTR”; PI20/01482-1 funded by the Instituto de Salud Carlos III, CB16/11/00222 funded by the Centro de Investigación Biomédica en Red en Enfermedades Cardiovasculares (CIBERCV) and a Grant (Proyectos 2021) financed by the Universidad Francisco de Vitoria
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