6,458 research outputs found

    Heat fluxes between the Guadalquivir river and the Gulf of Cádiz Continental Shelf

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    An 18-year time series of daily sea surface temperature of Gulf of Cadiz and an 18-month time series of temperature collected in the vicinity of the Guadalquivir estuary mouth have been analyzed to investigate the heat exchange between the estuary and the adjacent continental shelf. The first time identifies a continental shelf area where seasonal thermal oscillation signal (amplitudes and phase) changes abruptly. In order to explain this anomaly, the second data set allows a description of thermal fluctuations in a wide range of frequencies and an estimation of the upstream heat budget of the Guadalquivir estuary. Results show that high frequency thermal signal, diurnal and semidiurnal, and water flux signal through Guadalquivir mouth, mainly semidiurnal, apparently interact randomly to give a small exchange of thermal energy at high frequency. There is no trace, at the estuary's mouth, of daily heat exchanges with intertidal mudflats probably because it tends to cancel on daily time scales. Results also show that fluctuations of estimated air-sea fluxes force fluctuations of temperature in a quite homogeneous estuarine, with a delay of 20 days. The along-channel thermal energy gradient reaches magnitudes of 300-400 J m-4 near the mouth during the summer and winter and drives the estuary-shelf exchange of thermal energy at seasonal scale. Particularly, the thermal heat imported by the estuary from the shelf area during late fall-winter-early spring of 2008/2009 is balanced by the thermal heat that the estuary exports to the shelf area during late spring-summer of 2008. In summary, Guadalquivir river removes/imports excess of thermal energy towards/from the continental shelf seasonally, as a mechanism to accommodate excess of heat from one side respect to the other side.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Autoridad Portuaria de Sevilla (APS

    3D hydrodynamic model as a tool for more efficient port management and operations.

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    Ports have been attempting to increase their competitiveness by enhancing their productivity and operate in a more environmentally friendly way. The Port of Seville is located in the Guadalquivir River in the south of Spain and it is the unique Spanish inland port. The estuary has generated and is still generating conflicts of interests. The access channel to the port is being periodically dredged, the natural course has been anthropologically modified several times, original salt marshes have been transformed to grow rice and approximately one-fourth of the total surface of the estuary is now part of two protected areas, one of them is a UNESCO_MAB Biosphere Reserve. Despite its socio-economic and environmental significance there is a surprising lack of scientific and technical information about the environmental interactions between the port activities and the Guadalquivir estuary stakeholders. A 3D hydrodynamic model has been developed to study the tidal regime, water circulation, temperature and salinity distributions, flooding areas and the sediment dynamics in the estuary. The model output has been validated with in situ current speed, direction, water elevation and also with temperature and salinity measurements. Good agreement between modeled and real measurements have been obtained. Our preliminary results show that the vessel traffic management could be improved by using the tidal elevations and currents calculated by the model in the whole estuary. The interactions among the port activities (mainly due of changes in the sediments dynamics), the watershed management and the saline intrusion evolution will be studied in detail. 3D Hydrodynamic Modelling provide spatially explicit information on the key variables governing the dynamics of estuarine areas. The numerical model is a powerful tool to effectively guide the management and operations of ports located in a complex socio-ecological systems.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Naturalness of MSSM dark matter

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    There exists a vast literature examining the electroweak (EW) fine-tuning problem in supersymmetric scenarios, but little concerned with the dark matter (DM) one, which should be combined with the former. In this paper, we study this problem in an, as much as possible, exhaustive and rigorous way. We have considered the MSSM framework, assuming that the LSP is the lightest neutralino, χ10\chi_1^0, and exploring the various possibilities for the mass and composition of χ10\chi_1^0, as well as different mechanisms for annihilation of the DM particles in the early Universe (well-tempered neutralinos, funnels and co-annihilation scenarios). We also present a discussion about the statistical meaning of the fine-tuning and how it should be computed for the DM abundance, and combined with the EW fine-tuning. The results are very robust and model-independent and favour some scenarios (like the h-funnel when Mχ10M_{\chi_1^0} is not too close to mh/2m_h/2) with respect to others (such as the pure wino case). These features should be taken into account when one explores "natural SUSY" scenarios and their possible signatures at the LHC and in DM detection experiments.Comment: 28 pages, 18 figures. References added, matches JHEP published versio

    R&D expenditure in the EU: convergence or divergence?

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    This article examines the convergence of the R&D expenditure in the EU28 for 2004–2015. We initially run a sigma convergence analysis and the results show convergence in the total expenditure, due to the behaviour of the business and higher education sectors, despite government sector divergence. However, noticeable differences between the EU15 and 13 EU countries are apparent. The business enterprise sector is the main driver of EU15 R&D convergence, whereas for the EU13 this role is played by the government expenditure. In addition, the economic crisis has impacted differently on both groups. The club convergence approach allows us to explore these insights through individualized analysis and clusterization. Results for the EU28 show two clubs for the total expenditure, but the analysis of its components reveals a larger grouping. Our results evidence the necessity of revising the EU R&D policies towards greater coordination and resources, and the implementation of new instruments, due to the impact of this expenditure on growth, development and integration

    Sexual gender roles and stereotypes and the sexual double standard in sexual satisfaction among Portuguese college students: an exploratory study

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    This work was supported by the Fundação para a Ciência e a Tecnologia (FCT), under Grant number Fundação para a Ciência e a Tecnologia PTDC/PSI-GER/28530/2017Research on sexual satisfaction in Portugal is still limited; what exists, however, highlights barriers preventing optimal realisation of this dimension of sexuality and sexual health. Physical and relational barriers have been consistently evidenced, whereas social and cultural barriers have been less studied. Using focus groups, we aimed to explore perceptions of Portuguese college students (N = 47) about sexual satisfaction – more specifically, about gender differences and about how sexual gender roles and stereotypes and the Sexual Double Standard may influence sexual satisfaction. We found that sexual satisfaction is perceived to be suboptimal, especially for women in casual sexual relationships, and that the differences are attributed by both male and female to the constraints imposed by sexual gender roles, sexual gender stereotypes, and the sexual double standard. Deconstructing these socio-sexual beliefs is needed in order to achieve a higher, egalitarian level of sexual satisfaction and to promote sexual health.info:eu-repo/semantics/publishedVersio

    Portuguese College Students’ Perceptions About the Social Sexual Double Standard: Developing a Comprehensive Model for the Social SDS

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    Research on the sexual double standard (SDS) indicates its maintenance among college students, despite some attenuation and the emergence of alternative standards. Results show some inconsistencies, however, which highlight conceptual and methodological weaknesses that limit conclusions about the existence and expression of the SDS. One response entails distinguishing personal acceptance of the SDS from its social existence; maintenance of the SDS may reside in the latter, as there is some evidence for a decline in personal but not in social SDS. We aimed to analyse Portuguese college students’ perceptions about the social SDS and to develop a comprehensive model for it. Four male (n=30) and four female (n=17) focus groups were conducted with data analysis framed by Grounded Theory. The social SDS emerged especially with regard to casual sex and multiple partners, legitimized by the accepted/recognized existence of sexual gender roles and stereotypes. It is maintained through conformity with SDS and gender prescriptions in order to prove/ protect femininity, masculinity and sexual reputation. The process reduces sexual autonomy and has drawbacks for sexual health and wellbeing. Our comprehensive model can inform deconstructive strategies to promote egalitarian, liberal, and positive sexual experiences.info:eu-repo/semantics/publishedVersio

    EGCG Treatment on Ts65Dn Mice Suggests a Possible Correlation in Cognitive Development Deficit Reduction

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    poster abstractDown syndrome (DS) is caused by trisomy of human chromosome 21 (Ts21), affecting 1 in 700 live births. Ts21 results in about 80 phenotypes of which intellectual disability (ID) is one of the most debilitating. DYRK1A, found in 3 copies in individuals with Ts21 has been linked to alterations in morphology and function of the brain resulting in ID. Epigallocatechin-3-gallate (EGCG), a specific inhibitor of Dyrk1a activity has been hypothesized as a possible treatment for the overexpression of this gene, reducing the deficits caused by Dryk1a. Using the Ts65Dn mouse model, we examined the effects on hippocampal dependent learning and memory in the novel object recognition task (NOR) using mice of 3-6 weeks of age (adolescent mice). They were given free access to EGCG (0.124 mg/mL) in their drinking water for 21 days. They were then tested for cognitive improvement through NOR. Ts65Dn and control mice (treated and untreated) were subjected to 3 days of testing with 15 minute sessions per day consisting of habituation, exposure, and test day. All procedures were recorded and analyzed to determine time spent exploring novel object in relation to familiar. Our current results suggest that s65Dn mice do not spend as much time exploring the novel object as euploid mice and there exists a genotype effect, but treatment is not correcting the learning and memory deficit. We hypothesize that continuous EGCG treatment may be needed in order to see cognitive deficit reduction in adolescent mice

    Effects of EGCG Treatment of Ts65Dn Down Syndrome Mice on a Balance Beam Task

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    poster abstractDown syndrome (DS) is caused by trisomy of chromosome 21, and affects 1/700 live births. DS results in about 80 clinical phenotypes, including cognitive impairment. DYRK1A, a chromosome 21 gene, has been linked to alterations in morphology and function of the brain resulting in cognitive impairment. Epigallocatechin-3-gallate (EGCG), an inhibitor of DYRK1A activity, has been proposed as a possible treatment for cognitive deficits seen in individuals with DS. Using the Ts65Dn DS mouse model, we examined the effects of EGCG treatment on cerebellum dependent tasks using a balance beam test. We hypothesized that treatment with EGCG would improve Ts65Dn performance on the balance beam. In a first experiment, mice were given a dose of ~30 mg/kg/day EGCG, which showed no significant improvement in the balance beam task. In a second experiment, mice were given a dose of 100 mg/kg/day EGCG or water (control) starting at 3 weeks of age. The mice were handled two days before testing and then underwent a series of behavioral tasks including the balance beam test. The mice traversed three beams of differing widths (12, 9 and 6 mm), and three consecutive trials for each were recorded for further analysis. The balance beam recordings were scored by three independent scorers, blind to genotype and treatment, and the number of hind paw slips for each trial were scored. Our preliminary results indicate that the Ts65Dn mice are impaired at this task and have more hind paw slips compared to euploid controls. A larger number of animals should help to distinguish any differences in Ts65Dn mice due to EGCG treatment

    Effects of 50 mg/kg EGCG Treatment of Ts65Dn Down Syndrome Mice on Novel Object Recognition

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    poster abstractDown syndrome (DS) is caused by trisomy of chromosome 21, and affects 1/700 live births. DYRK1A, a gene found in three copies in humans with DS and Ts65Dn DS mice, has been linked to alterations in morphology and function of the brain resulting in cognitive impairment. Epigallocatechin-3-gallate (EGCG), an inhibitor of DYRK1A activity, has been proposed as a possible treatment. Using the Ts65Dn DS mouse model, we examined the effects of EGCG treatment on on hippocampal dependent learning and memory using a novel object recognition task (NOR). A previous study analyzing the effects of EGCG at a concentration 30mg/kg/day showed that there was no genotype or treatment effect in the NOR task when treatment is continuous through testing. In this study, the mice were given 50 mg/kg/day EGCG or water via their drinking water starting at 3 weeks of age. The mice were handled two days before testing and then underwent a series of behavioral tests including NOR. They underwent testing at 3 weeks and 7 weeks of treatment. Treatment was continuous throughout behavioral testing. NOR consists of a box with the objects placed diagonally from each other. The mice underwent 3 days of testing with 15 minute sessions per day consisting of habituation, exposure, and test day, all of which were recorded and analyzed to determine time spent exploring novel object in relation to familiar. The amount of time spent at each object was scored by three independent scorers, blind to genotype and treatment. We observed no genotype or treatment effect at either the 3 or 7 week test results, which is consistent with our past results. A higher dose, along with a more sensitive test of recognition memory, may be needed in order to show a treatment effect on the Ts65Dn mice

    Cladistic Parsimony Analysis of Internal Transcribed Spacer Region (nrDNA) Sequences of Bouteloua and Relatives (Gramineae: Chloridoideae)

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    Chloridoideae) employing cladistic parsimony analysis of nuclear ribosomal internal transcribed spacer region (ITS1 + 5.8S + ITS2) DNA sequences. Included were Aegopogon (2 of 4 species), Bouteloua (34 of 42), Buchloë (1 of 1), Buchlomimus (1 of 1), Cathestecum (2 of 4), Cyclostachya (1 of 1), Griffithsochloa (1 of 1), Hilaria (1 of 7), Opizia (2 of 2), Pentarrhaphis (2 of 3), Pleuraphis (2 of 3), Pringleochloa (1 of 1), Soderstromia (1 of 1), and five outgroup genera/species for a total of I8 genera, 56 species, and ten varieties. In all, the ITS region of 72 plants was sequenced and analyzed utilizing PAUP. Aegopogon, the Hilaria-Pleuraphis clade, and Tragus (an outgroup representative) formed a tetratomy with a clade containing the remaining ingroup taxa. Neither Bouteloua nor its two subgenera, Bouteloua and Chondrosium, were found to be monophyletic. Bouteloua chondrosioides was sister to Opizia. Bouteloua rigidiseta formed a clade with Buchlomimus and Pringleochloa. Bouteloua eludens formed a clade with Buchloë, Cathestecum, Griffithsochloa, Pentarrhaphis, and Soderstromia. Bouteloua annua and B. aristidoides (subg. Bouteloua) formed a clade with B. eriopoda, B. eriostachya, B. hirsuta, and B. pectinata (subg. Chondrosium). Bouteloua juncea, which has been included in the B. curtipendula complex, was not a member of that clade. No new circumscriptions were proposed, although recognition of Bouteloua in the broad sense, with Chondrosium reduced to synonymy, was advocated. The findings suggested homoplasy in morphological, anatomical, and breeding system traits
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