2,349 research outputs found
A Central Georgia Asthma Prevalence Assessment of School-Age Children and Compliance with Senate Bill 472
Background: A common theme among the counties of the North Central Health District is the disparity between the number of asthma-related visits of African-American and white children ages 1-14 to the emergency department. In 2013, 858 children ages 1-14 in the district had emergency room visits related to asthma. The purpose of this study was to assess North Central Health District (NCHD) schools to determine the prevalence of self-reported asthma by parents and school age children and the adequacy of students’ access to maintenance inhalers at school, and to identify schools that qualify for Asthma Friendly School Recognition.
Methods: The “Asthma School Policy Assessment” from the 2015 Georgia Asthma-Friendly Schools Toolkit and Recognition Guidance was used to assess policies and practices for addressing asthma with school staff, parents, and children within the NCHD schools. The Lead School Nurses in each of the 13 counties were contacted in the fall of 2015 via email to request their participation in the assessment. Each was sent a link via email to complete the consent and assessment online; Lead Nurses then sent the link to their team nurses. Data were analyzed using descriptive statistics. IRB approval was obtained from Mercer University.
Results: The findings from the study indicate that 75% of the reporting schools have asthmatic students enrolled. The number of students with asthma ranged from 5 to 79 per school. However, only two reporting schools could identify a medication policy that allows children to possess and self-administer asthma medication. Furthermore, none of the schools reported having all five policies necessary to obtain Asthma Friendly School recognition.
Conclusions: The results indicate a need for school health nurse training to ensure schools implement and adhere to policies to reduce asthma disparities among school age children as outlined in the 2015 Georgia Asthma-Friendly Schools Toolkit and Recognition Guidance
Forest landscape restoration in the drylands of Latin America
Forest Landscape Restoration (FLR) involves the ecological restoration of degraded forest landscapes, with the aim of benefiting both biodiversity and human well-being. We first identify four fundamental principles of FLR, based on previous definitions. We then critically evaluate the application of these principles in practice, based on the experience gained during an international, collaborative research project conducted in six dry forest landscapes of Latin America. Research highlighted the potential for FLR; tree species of high socioeconomic value were identified in all study areas, and strong dependence of local communities on forest resources was widely encountered, particularly for fuelwood. We demonstrated that FLR can be achieved through both passive and active restoration approaches, and can be cost-effective if the increased provision of ecosystem services is taken into account. These results therefore highlight the potential for FLR, and the positive contribution that it could make to sustainable development. However, we also encountered a number of challenges to FLR implementation, including the difficulty of achieving strong engagement in FLR activities among local stakeholders, lack of capacity for community-led initiatives, and the lack of an appropriate institutional and regulatory environment to support restoration activities. Successful implementation of FLR will require new collaborative alliances among stakeholders, empowerment and capacity building of local communities to enable them to fully engage with restoration activities, and an enabling public policy context to enable local people to be active participants in the decision making process. © 2012 by the author(s). Published here under license by the Resilience Alliance
Underexpanded gas jets of Mach 2: the changing physical structure and power transmission
Supersonic jets with excess gas pressure are associated with many phenomena including radio galaxies, protostars, volcanic plumes, rocket exhausts, and champagne cork popping. Some common properties are derived here based on steady uniform hydrodynamic flow from a circular orifice. We present a systematic numerical study over a wide range of parameters for Mach 2 jets, concentrating on simulations of jets with pressures exceeding the ambient pressure. With cylindrical symmetry, we show how the location of the stand-off and following downstream shocks depend not only on the overpressure but also on the density due to a feedback loop, which results in an oscillatory flow pattern. We conclude that rapidly varying and gradually evolving shock patterns arise even from steady uniform jets. This can take the form of turbulent plumes at high overpressures and regular oscillations at low overpressures. We identify where this screeching contributes to noise and sound wave generation, which may aid the regulation of star and galaxy formation. However, the main effect for such low Mach number jets is to drive a circulatory motion in which the ambient medium is driven out along the axial direction while mass and energy flow laterally inwards, setting up a large advection pattern. Once the initial bow shock has propagated out, the noise from the jet is insufficient to significantly alter the environment. High Mach number jets do not follow these conclusions and will be treated separately
Asymptotic information leakage under one-try attacks
We study the asymptotic behaviour of (a) information leakage and (b) adversary’s error probability in information hiding systems modelled as noisy channels. Specifically, we assume the attacker can make a single guess after observing n independent executions of the system, throughout which the secret information is kept fixed. We show that the asymptotic behaviour of quantities (a) and (b) can be determined in a simple way from the channel matrix. Moreover, simple and tight bounds on them as functions of n show that the convergence is exponential. We also discuss feasible methods to evaluate the rate of convergence. Our results cover both the Bayesian case, where a prior probability distribution on the secrets is assumed known to the attacker, and the maximum-likelihood case, where the attacker does not know such distribution. In the Bayesian case, we identify the distributions that maximize the leakage. We consider both the min-entropy setting studied by Smith and the additive form recently proposed by Braun et al., and show the two forms do agree asymptotically. Next, we extend these results to a more sophisticated eavesdropping scenario, where the attacker can perform a (noisy) observation at each state of the computation and the systems are modelled as hidden Markov models
Surface Modification of Polyethylene with Multi-End-Functional Polyethylene Additives
We have prepared and characterized a series of multifluorocarbon end-functional polyethylene additives, which when blended with polyethylene matrices increase surface hydrophobicity and lipophobicity. Water contact angles of >112° were observed on spin-cast blended film surfaces containing less than 1% fluorocarbon in the bulk, compared to 98° in the absence of any additive. Crystallinity in these films gives rise to surface roughness that is an order of magnitude greater than is typical for amorphous spin-cast films but is too little to give rise to superhydrophobicity. X-ray photoelectron spectroscopy (XPS) confirms the enrichment of the multifluorocarbon additives at the air surface by up to 80 times the bulk concentration. Ion beam analysis was used to quantify the surface excess of the additives as a function of composition, functionality, and molecular weight of either blend component. In some cases, an excess of the additives was also found at the substrate interface, indicating phase separation into self-stratified layers. The combination of neutron reflectometry and ion beam analysis allowed the surface excess to be quantified above and below the melting point of the blended films. In these films, where the melting temperatures of the additive and matrix components are relatively similar (within 15 °C), the surface excess is almost independent of whether the blended film is semicrystalline or molten, suggesting that the additive undergoes cocrystallization with the matrix when the blended films are allowed to cool below the melting point
Time-reversal violating rotation of polarization plane of light in gas placed in electric field
Rotation of polarization plane of light in gas placed in electric field is
considered. Different factors causing this phenomenon are investigated. Angle
of polarization plane rotation for transition 6S_{1/2} - 7S_{1/2} in cesium
(lambda=539 nm) is estimated. The possibility to observe this effect
experimentally is discussed.Comment: 10 pages, Late
Confound modelling in UK Biobank brain imaging
© 2020 Dealing with confounds is an essential step in large cohort studies to address problems such as unexplained variance and spurious correlations. UK Biobank is a powerful resource for studying associations between imaging and non-imaging measures such as lifestyle factors and health outcomes, in part because of the large subject numbers. However, the resulting high statistical power also raises the sensitivity to confound effects, which therefore have to be carefully considered. In this work we describe a set of possible confounds (including non-linear effects and interactions that researchers may wish to consider for their studies using such data). We include descriptions of how we can estimate the confounds, and study the extent to which each of these confounds affects the data, and the spurious correlations that may arise if they are not controlled. Finally, we discuss several issues that future studies should consider when dealing with confounds
Association Between Episodic Memory and Genetic Risk Factors for Alzheimer’s Disease in South Asians from the Longitudinal Aging Study in India–Diagnostic Assessment of Dementia (LASI‐DAD)
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156473/3/jgs16735-sup-0001-supinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156473/2/jgs16735_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156473/1/jgs16735.pd
- …