4,739 research outputs found

    Earnings and Percentage Female: A Longitudinal Study

    Get PDF
    Comparable worth is designed to raise the earnings of women assumed to be penalized for working in female-dominated occupations. Comparable worth advocates assume that the relation between earnings and percentage female in an occupation is due to crowding or other forms of discrimination. An alternative explanation is that the relation stems from women freely choosing different occupations. In other words, preferences are an omitted variable. In our study, we first replicate previous research that has used cross-sectional data to find a negative relation between earnings and percentage female (in an occupation) for both men and women. However, using longitudinal data to control for time-invariant omitted variables, we find that while men\u27s estimated penalty is not reduced, the percentage female penalty falls substantially for women and is not statistically significant. These results imply that estimates of the percentage female effect based on cross-sectional data may be inflated for women. An exception to this general finding is that women with intermittent labor force participation do experience a sizeable penalty for working in female-dominated occupations. Hence, this pattern of results suggests that a comparable worth policy would most likely benefit women with discontinuous employment--perhaps an unintended outcome

    Impact of fill factor on input current ripple of photovoltaic system

    Get PDF
    This paper discusses the impact of fill factor on the input current ripple of the photovoltaic module and the loss effect on power extracted. Photovoltaic module's P-V curve produces exponential curve. The curvature of this curve indicates the fill factor of the particular cell; hence, by increasing the fill factor, the available extracted power increases. Yet, this paper states that losses due to photovoltaic current increases by increasing the fill factor

    Novel variations in spatial relations between the facial nerve and superficial temporal and maxillary veins

    Get PDF
    Variations in the relationship of the retromandibular vein to the facial nerve have been widely reported due to their relevance for surgical approaches in parotid, osteotomy and mandibular condyle surgery. In the context of the retromandibular retroparotid approach, remaining deep to the retromandibular vein is advised to decrease the likelihood of encountering the facial nerve during mandibular condyle surgery. In the present report, an unusual variant of the superficial temporal vein lying superficial to the facial nerve is described. This represents a variation of the venous branching pattern within the parotid gland, whereby the superficial temporal vein joins the maxillary vein inferior to its usual communication. These findings are discussed in the context of commonly used surgical approaches to the mandible for condylar trauma or osteotomy surgery

    Rapid holographic phase transition with brane-localized curvature

    Get PDF
    We study the finite-temperature properties of the Randall-Sundrum model in the presence of brane-localized curvature. At high temperature, as dictated by AdS/CFT, the theory is in a confined phase dual to the planar AdS black hole. When the radion is stabilized, à la Goldberger-Wise, a holographic first-order phase transition proceeds. The brane-localized curvature contributes to the radion kinetic energy, substantially decreasing the critical bubble energy. Contrary to previous results, the phase transition completes at much larger values of N , the number of degrees of freedom in the CFT. Moreover, the field value of the bulk scalar on the TeV-brane is allowed to become large, while remaining consistent with back-reaction constraints. Assisted by this fact, we find that for a wide region in the parameter space tunneling happens rather quickly, i.e. the nucleation temperature becomes of the order of the critical temperature. At zero temperature, the most important signature of brane-localized curvature is the reduction of spin-2 Kaluza-Klein graviton masses and a heavier radion

    Efficient algorithms to solve atom reconfiguration problems. I. The redistribution-reconfiguration (red-rec) algorithm

    Full text link
    We propose the redistribution-reconfiguration~(red-rec) algorithm to efficiently compute control protocols to assemble compact-centered configurations of atoms in two-dimensional arrays of optical traps with lattice geometries. The red-rec algorithm redistributes atoms among pairs of donor-receiver columns and reconfigures each column using an exact displacement-minimizing algorithm, harnessing parallel control operations that simultaneously actuate multiple traps to reduce the execution time. We numerically quantify the performance of the red-rec algorithm, both in the absence and in the presence of loss, using realistic physical parameters and operational constraints. We show that the number of traps required to prepare a compact-centered configuration of atoms on a grid with a mean success probability of one half scales as the 3/2 power of the number of desired atoms, highlighting the challenges of assembling configurations of tens of thousands of atoms. We further demonstrate that faster preparation times can be achieved by rejecting configurations of atoms containing fewer atoms than a given threshold. The red-rec algorithm admits an efficient implementation that can readily be deployed on real-time control systems to assemble large configurations of atoms with high mean success probability and fast preparation times.Comment: 13 pages, 7 figure

    Enjeux et impacts des barrages de Diama (Mauritanie) et Arzal (France) : des contextes socio-économiques et environnementaux différents pour de mêmes conséquences

    Get PDF
    The similar dams of Arzal (Vilaine, France) and Diama (Mauritania-Senegal frontier) have same strategic functions for the regions and countries where they are built as fresh waters storage. They also had similar consequences over the ecosystems and local and regional activities. The imperfect results of the belated remediations also had as disastrous induced effects and leave the populations and ecosystems in a fragile and vulnerable situation if confronted with any environmental (drought, flood…), socio-economical or political (relations between Mauritania and Senegal) crisis

    Dopamine Activation Preserves Visual Motion Perception Despite Noise Interference of Human V5/MT

    Get PDF
    Copyright © 2016 Yousif et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License Creative Commons Attribution 4.0 International, which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.When processing sensory signals, the brain must account for noise, both noise in the stimulus and that arising from within its own neuronal circuitry. Dopamine receptor activation is known to enhance both visual cortical signal-to-noise-ratio (SNR) and visual perceptual performance; however, it is unknown whether these two dopamine-mediated phenomena are linked. To assess this, we used single-pulse transcranial magnetic stimulation (TMS) applied to visual cortical area V5/MT to reduce the SNR focally and thus disrupt visual motion discrimination performance to visual targets located in the same retinotopic space. The hypothesis that dopamine receptor activation enhances perceptual performance by improving cortical SNR predicts that dopamine activation should antagonize TMS disruption of visual perception. We assessed this hypothesis via a double-blinded, placebo-controlled study with the dopamine receptor agonists cabergoline (a D2 agonist) and pergolide (a D1/D2 agonist) administered in separate sessions (separated by 2 weeks) in 12 healthy volunteers in a William's balance-order design. TMS degraded visual motion perception when the evoked phosphene and the visual stimulus overlapped in time and space in the placebo and cabergoline conditions, but not in the pergolide condition. This suggests that dopamine D1 or combined D1 and D2 receptor activation enhances cortical SNR to boost perceptual performance. That local visual cortical excitability was unchanged across drug conditions suggests the involvement of long-range intracortical interactions in this D1 effect. Because increased internal noise (and thus lower SNR) can impair visual perceptual learning, improving visual cortical SNR via D1/D2 agonist therapy may be useful in boosting rehabilitation programs involving visual perceptual training.Peer reviewe

    Characterisation of the effects of mutation of the caldesmon sequence 691glu-trp-leu-thr-lys-thr696 to pro-gly-his-tyr-asn-asn on caldesmon-calmodulin interaction

    Get PDF
    AbstractWe have investigated the functional properties of a mutant (Cg1) derived from the C-terminal 99 amino acids of chicken caldesmon, 658–756 (658C) where the sequence 691glu-trp-leu-thr-lys-thr696 is changed to pro-gly-his-tyr-asn-asn. Cg1 bound Ca2+-calmodulin with (1/7)th of the affinity as compared to 658C or whole caldesmon. NMR titrations indicate that the contacts of Ca2+-calmodulin with the Trp-722 region of the peptide are retained but that those at the mutated site are lost. Most importantly Ca2+-calmodulin is not able to reverse the Cg1-induced inhibition. We conclude that the interaction of calmodulin with this caldesmon sequence is crucial for the reversal of caldesmon inhibition of actin-tropomyosin activation of myosin ATPase. The results are interpreted in terms of multi-site attachment of actin and Ca2+-calmodulin to overlapping sequences in caldesmon domain 4b

    Aerosol delivery of trail pheromone disrupts the foraging of the red imported fire ant, \u3ci\u3eSolenopsis invicta\u3c/i\u3e

    Get PDF
    BACKGROUND: The fire ant, Solenopsis invicta, is one of the most aggressive and invasive species in the world. The trail pheromone Z,E-α-farnesene (91% purity)was prepared, and disruption of worker trail orientation was tested using an ethanol based aerosol formulation presenting a single puff of this compound by airbrush and compressed air. Trail-following behavior was recorded by overhead webcam and ants digitized before and after presentation of the aerosol treatment at four rates (1.6, 16, 160 and 1600 ng cm−2). RESULTS: Ants preferred 110 ng cm−1 over 11, 1.1 and 0.11 ng cm−1 for trail following. Within seconds of presentation of 1600 ng cm−2, the highest dose tested, trail disruption was observed. Disruption was evident as reduced arrival success and reduction in the trail integrity statistic (r2), as well as increased deviation from the trail (deg). The distribution of walking track angles was also flattened. CONCLUSIONS: The feasibility of using aerosol for delivery of trail pheromone was demonstrated, but the need for high purity combined with the difficulty of commercial supply makes this technique impractical. However, the commercial production of Z,E-α-farnesene of high purity by industrial biotechnology or from (E)-nerolidol may be possible in future, which would facilitate further development of trail pheromone disruption of S. invicta
    • …
    corecore