58 research outputs found

    Sunshine, Fertility and Racial Disparities

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    This research investigates the effect of sun exposure on fertility, with a special focus on how its effects and consequences for birth outcomes may differ by race. Sun exposure is a key mechanism for obtaining Vitamin D, but this process is inhibited by skin pigmentation. Vitamin D has been linked to male and female fertility and risk of miscarriage, and Vitamin D deficiency is more prevalent among blacks than whites. Using 1989–2004 individual live births data from the Natality Detail Files, county-level, monthly conceptions are estimated as a function of monthly solar insolation, temperature and humidity, as well as month, time and location fixed effects and controls. Insolation has positive, statistically significant effects on fertility for both non Hispanic blacks and whites, but the effects are stronger and the pattern of effect different for black mothers than whit

    Analyse exploratoire de quatre Centres de la petite enfance au Nunavik

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    Cette étude exploratoire décrit le processus d'instauration de plusieurs Centres de la petite enfance (CPE) en lien avec le contexte socioéconomique de quatre villages au Nunavik en 2011. L'objet de ce mémoire est d'analyser les conditions communautaires, telles que l'emploi, la santé, les services de garde à l'enfance et l'éducation, qui ont engendré la demande des services de CPE, ainsi que d'examiner l'influence qu'ont ces services sur la vie communautaire. Le développement de ces services dérive d'une collaboration entre l'Administration régionale Kativik (ARK) et les membres des communautés nordiques. Ainsi, nous examinons la part de l'ARK dans son soutien des services de garde à l'enfance dans le Nord. À ce jour, il existe peu de recherches scientifiques effectuées sur ces services au Nunavik et nous avons travaillé en partenariat avec l'ARK afin de réaliser ce projet.This exploratory research, conducted in 2011, describes the implementation of several childcare centres within a socioeconomic context in four communities in Nunavik. The main objectives of this project are to analyze community conditions such as employement possibilities, health issues, childcare services and education, that engendered a demand for childcare centres, as well as to examine the impact of such services on community life. The development of childcare centres derives from a collaboration between the Kativik Regional Government (KRG) and Northern community members. Hence, we also explore the role KRG played in the developement and maintance of such services in the North. To this day, there exists few scientific studies dealing with childcare centres in Nunavik and so, we worked in collaboration with KRG to conduct this project

    Water System Unreliability and Diarrhea Incidence Among Children in Guatemala

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    OBJECTIVES: This article examines the effect of water system unreliability on diarrhea incidence among children aged 0-5 in Guatemala. METHODS: We use secondary data from a nationally representative sample of 7579 children to estimate the effects of uninterrupted and interrupted water services on diarrhea incidence. The national scope of this study imposes some methodological challenges due to unobserved geographical heterogeneity. To address this issue, we estimate mixed-effects logit models that control for unobserved heterogeneity by estimating random effects of selected covariates that can vary across geographical areas (i.e. water system reliability). RESULTS: Compared to children without access to piped water, children with uninterrupted water services have a lower probability of diarrhea incidence by approximately 33 percentage points. Conversely, there is no differential effect between children without access and those with at least one day of service interruptions in the previous month. Results also confirm negative effects of age, female gender, spanish language, and garbage disposal on diarrhea incidence. CONCLUSIONS: Public health benefits of piped water are realized through uninterrupted provision of service, not merely access. Policy implications are discussed

    Koinonia

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    Conference SpotlightSpirituality, Religion, and the Undergraduate College Student, Jennifer Lindholm ACSD 2005 Artist Spotlight: Shaun Groves Ideas for Our WorkThinking Theologically: The Moral of a Good Story, Todd C. Ream Changing Our Name and Identity: Rebranding or Renewal, Dana Alexander FeaturesThe President\u27s Corner Editor\u27s Diskhttps://pillars.taylor.edu/acsd_koinonia/1008/thumbnail.jp

    Modification of hERG1 channel gating by Cd2+

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    Each of the four subunits in a voltage-gated potassium channel has a voltage sensor domain (VSD) that is formed by four transmembrane helical segments (S1–S4). In response to changes in membrane potential, intramembrane displacement of basic residues in S4 produces a gating current. As S4 moves through the membrane, its basic residues also form sequential electrostatic interactions with acidic residues in immobile regions of the S2 and S3 segments. Transition metal cations interact with these same acidic residues and modify channel gating. In human ether-á-go-go–related gene type 1 (hERG1) channels, Cd2+ coordinated by D456 and D460 in S2 and D509 in S3 induces a positive shift in the voltage dependence of activation of ionic currents. Here, we characterize the effects of Cd2+ on hERG1 gating currents in Xenopus oocytes using the cut-open Vaseline gap technique. Cd2+ shifted the half-point (V1/2) for the voltage dependence of the OFF gating charge–voltage (QOFF-V) relationship with an EC50 of 171 µM; at 0.3 mM, V1/2 was shifted by +50 mV. Cd2+ also induced an as of yet unrecognized small outward current (ICd-out) upon repolarization in a concentration- and voltage-dependent manner. We propose that Cd2+ and Arg residues in the S4 segment compete for interaction with acidic residues in S2 and S3 segments, and that the initial inward movement of S4 associated with membrane repolarization displaces Cd2+ in an outward direction to produce ICd-out. Co2+, Zn2+, and La3+ at concentrations that caused ∼+35-mV shifts in the QOFF-V relationship did not induce a current similar to ICd-out, suggesting that the binding site for these cations or their competition with basic residues in S4 differs from Cd2+. New Markov models of hERG1 channels were developed that describe gating currents as a noncooperative two-phase process of the VSD and can account for changes in these currents caused by extracellular Cd2+

    Number of years of participation in some, but not all, types of physical activity during adolescence predicts level of physical activity in adulthood: Results from a 13-year study

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    Abstract: Background: Adolescent physical activity (PA) levels track into adulthood. However it is not known if type of PA participated in during adolescence is associated with PA levels later in life. We aimed to identify natural groupings of types of PA and to assess whether number of years participating in these different groupings during adolescence is related to PA level in early adulthood. Methods: 673 adolescents in Montreal, Canada, age 12–13 years at baseline (54 % female), reported participation in 29 physical activities every 3 months over 5 years (1999–2005). They also reported their PA level at age 24 years (2011–12). PA groupings among the 29 physical activities were identified using factor analysis. The association between number of years participating in each grouping during adolescence and PA level at age 24 was estimated using linear regression within a general estimating equation framework. Results: Three PA groupings were identified: “sports”, “fitness and dance”, and “running”. There was a positive linear relationship between number of years participating in sports and running in adolescence and PA level at age 24 years (β (95 % confidence interval) = 0.09 (0.04-0.15); 0.08 (0.01-0.15), respectively). There was no relationship between fitness and dance in adolescence and PA level at age 24. Conclusions: The association between PA participation in adolescence and PA levels in young adulthood may be specific to certain PA types and to consistency of participation during adolescence. Results suggest that efforts to establish the habit of participation in sports and running in adolescence may promote higher PA levels in adulthood

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

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    Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

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    Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

    Ultralight vector dark matter search using data from the KAGRA O3GK run

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    Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
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