126 research outputs found

    Spatial variation and antecedent sea surface temperature conditions influence Hawaiian intertidal community structure

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    Global sea surface temperatures (SSTs) are increasing, and in Hawaiʻi, rates of ocean warming are projected to double by the end of the 21st century. However, current nearshore warming trends and their possible impacts on intertidal communities are not well understood. This study represents the first investigation into the possible effects of rising SST on intertidal algal and invertebrate communities across the Main Hawaiian Islands (MHI). By utilizing citizen-science data coupled with high-resolution, daily SST satellite measurements from 12 intertidal sites across the MHI from 2004–2019, the response of intertidal algal and invertebrate abundance and community diversity to changes in SST was investigated across multiple spatial scales. Results show high rates of SST warming (0.40°C Decade-1) over this study’s timeframe, similar to predicted rates of warming for Hawaiʻi by the end of the 21st century. Changes in abundance and diversity in response to SST were variable among intertidal sites, but differences in antecedent SST among intertidal sites were significantly associated with community dissimilarity. In addition, a statistically significant positive relationship was found between SST and Simpson’s diversity index, and a significant relationship was also found between SST and the abundance of six dominant taxa. For five of these six dominant taxa, antecedent SSTs over the 6–12 months preceding sampling were the most influential for describing changes to abundance. The increase in community diversity in response to higher SSTs was best explained by temperatures in the 10 months preceding sampling, and the resultant decreased abundance of dominant turf algae. These results highlight rapidly warming nearshore SSTs in Hawaiʻi and the longer-term effects of antecedent SSTs as significant drivers of change within Hawaiian intertidal communities. Therefore, we suggest that future research and management should consider the possibility of lagging effects of antecedent SST on intertidal communities in Hawaiʻi and elsewhere

    Quantum phase transition in the Frenkel-Kontorova chain: from pinned instanton glass to sliding phonon gas

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    We study analytically and numerically the one-dimensional quantum Frenkel-Kontorova chain in the regime when the classical model is located in the pinned phase characterized by the gaped phonon excitations and devil's staircase. By extensive quantum Monte Carlo simulations we show that for the effective Planck constant \hbar smaller than the critical value c\hbar_c the quantum chain is in the pinned instanton glass phase. In this phase the elementary excitations have two branches: phonons, separated from zero energy by a finite gap, and instantons which have an exponentially small excitation energy. At =c\hbar=\hbar_c the quantum phase transition takes place and for >c\hbar>\hbar_c the pinned instanton glass is transformed into the sliding phonon gas with gapless phonon excitations. This transition is accompanied by the divergence of the spatial correlation length and appearence of sliding modes at >c\hbar>\hbar_c.Comment: revtex 16 pages, 18 figure

    Patient-Reported Outcomes Through 1 Year of an HIV-1 Clinical Trial Evaluating Long-Acting Cabotegravir and Rilpivirine Administered Every 4 or 8 Weeks (ATLAS-2M)

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    BACKGROUND: Advances in HIV-1 therapeutics have led to the development of a range of daily oral treatment regimens, which share similar high efficacy rates. Consequently, more emphasis is being placed upon the individual\u27s experience of treatment and impact on quality of life. The first long-acting injectable antiretroviral therapy for HIV-1 (long-acting cabotegravir + rilpivirine [CAB + RPV LA]) may address challenges associated with oral treatment for HIV-1, such as stigma, pill burden/fatigue, drug-food interactions, and adherence. Patient-reported outcomes (PROs) collected in an HIV-1 clinical trial (ATLAS-2M; NCT03299049) comparing participants\u27 experience with two dosing regimens (every 4 weeks [Q4W] vs. every 8 weeks [Q8W]) of CAB + RPV LA are presented herein. METHODS: PRO endpoints evaluated through 48 weeks of therapy included treatment satisfaction (HIV Treatment Satisfaction Questionnaire [HIVTSQ]), treatment acceptance ( General Acceptance domain of the Chronic Treatment Acceptance [ACCEPT RESULTS: Overall, 1045 participants were randomized to the Q8W (n = 522) and Q4W (n = 523) regimens; 37% (n = 391/1045) had previously received CAB + RPV in ATLAS. For participants without prior CAB + RPV exposure, large increases from baseline were reported in treatment satisfaction in both long-acting arms (HIVTSQ status version), with Q8W dosing statistically significantly favored at Weeks 24 (p = 0.036) and 48 (p = 0.004). Additionally, improvements from baseline were also observed in the General Acceptance domain of the ACCEPT questionnaire in both long-acting arms for participants without prior CAB + RPV exposure; however, no statistically significant difference was observed between arms at either timepoint (Week 24, p = 0.379; Week 48, p = 0.525). Significant improvements (p \u3c 0.001) in the Acceptance of Injection Site Reactions domain of the PIN questionnaire were observed from Week 8 to Weeks 24 and 48 in both arms for participants without prior CAB + RPV exposure. Participants with prior CAB + RPV exposure reported high treatment satisfaction (mean [HIVTSQ status version]: Q8W 62.2/66.0; Q4W 62.0/66.0), treatment acceptance (mean: Q8W 89.3/100; Q4W 91.2/100), and acceptance of injection site reactions (mean [5 = not at all acceptable; 1 = totally acceptable]: Q8W 1.72; Q4W 1.59) at baseline/Week 8 that were maintained over time. Participants without prior CAB + RPV exposure who received Q8W dosing preferred this regimen over oral CAB + RPV (98%, n = 300/306). Among those with prior Q4W exposure, 94% (n = 179/191) preferred Q8W dosing versus Q4W dosing (3%, n = 6/191) or oral CAB + RPV (2%, n = 4/191). CONCLUSIONS: Both long-acting regimens provided high treatment satisfaction and acceptance, irrespective of prior CAB + RPV exposure, with most participants preferring Q8W dosing over both the Q4W regimen and their previous daily oral regimen. The PRO data collected at Week 48 support the therapeutic potential of CAB + RPV LA. FUNDING: ViiV Healthcare and Janssen. TRIAL REGISTRATION: ATLAS-2M: ClinicalTrials.gov NCT03299049, registered October 2, 2017

    Unemployment Insurance and Low-Educated Single Working Mothers Before and After Welfare Reform

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    Using the Survey of Income and Program Participation (SIPP), a nationally representative, longitudinal survey, this study examines changing levels of Unemployment Insurance (UI) eligibility and benefit receipt among working low-educated single mothers, 1990–2005. It also examines changing participation in cash welfare and the Food Stamp Program (FSP). Relative to single childless women, there has been no increase in UI benefit receipt among single mothers entering a spell of unemployment in the postreform period, even though single mothers have increased their relative rates of UI eligibility. Because of declining cash assistance receipt, UI became a more common income support than cash assistance for this population during the period 2001–2005. Furthermore, the probability of accessing FSP for low-educated single mothers entering a spell of unemployment increased in the years 2001–2005. As a result, the proportion of this population accessing benefits from one or more of these programs remained virtually unchanged across the study period

    Supernova Bounds on Resonant Active-Sterile Neutrino Conversions

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    We discuss the effects of resonant νeνs\nu_e \to \nu_s and νˉeνˉs\bar{\nu}_e \to \bar{\nu}_s (νs\nu_s is a sterile neutrino) conversions in the dense medium of a supernova. In particular, we assume the sterile neutrino νs\nu_s to be in the hot dark matter few eV mass range. The implications of such a scenario for the supernova shock re-heating, the detected νˉe\bar\nu_e signal from SN1987A and for the r-process nucleosynthesis hypothesis are analysed in some detail. The resulting constraints on mixing and mass difference for the νeνs\nu_e-\nu_s system are derived. There is also an allowed region in the neutrino parameter space for which the r-process nucleosynthesis can be enhanced.Comment: Latex file, 27 pages including 10 ps figures, uses psfig.sty. Few references added, some change in the Acknowledgements and some minor corrections in the tex

    Change in left ventricular geometry during antihypertensive treatment in children with primary hypertension

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    The pattern of the left ventricle (LV) has important significance in adults with hypertension. The aim of the present study was to analyze changes and determinants of LV geometry after 1 year of antihypertensive treatment in children with primary hypertension (PH) in relation to metabolic abnormalities and anthropometrical parameters. In 86 children (14.1 ± 2.4 years) with newly diagnosed PH, LV geometry and biochemical parameters before and after 12 months of standard antihypertensive therapy were assessed. At baseline, normal LV geometry (NG) was found in 42 (48.9%), concentric remodeling (CR) in 4 (4.6%), concentric hypertrophy (CH) in 8 (9.3%), and eccentric hypertrophy (EH) in 32 (37.2%) patients. The prevalence of NG in patients with severe hypertension was significantly lower than in patients with ambulatory hypertension. There were no differences in dipping status in relation to LV geometry. Patients with CH and EH were more viscerally obese than patients with NG. Patients with CH had higher diastolic blood pressure in comparison with EH patients (p < 0.05). The main predictor of relative wall thickness (RWT) was the triglycerides to high density lipoprotein cholesterol (TG/HDL) ratio (R2 = 0.319, β = 0.246, p = 0.004). Patients received 12 months of antihypertensive treatment, either lifestyle modification only (n = 37) or lifestyle modification plus antihypertensive medications (n = 49) if severe ambulatory hypertension or target organ damage were present. After 12 months of treatment the prevalence of EH (37.2% vs 18.6%, p = 0.003) decreased but prevalence of CH did not change. Patients in whom RWT decreased also decreased waist circumference and TG/HDL; the main predictor of RWT decrease was a decrease of the TG/HDL ratio (β = 0.496, R2 = 0.329, p = 0.002). In adolescents with PH, LV geometry is related to central obesity and insulin resistance. Decrease of abdominal obesity and insulin resistance are the most important predictors of normalization of LV geometry, however CH has lower potential to normalize LV geometry
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