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Integrating research, surveillance, and practice in environmental public health tracking.
The Centers for Disease Control and Prevention in the U.S. Department of Health and Human Services is working with selected state and local health departments, academic centers, and others to develop an environmental public health tracking initiative to improve geographic and temporal surveillance of environmental hazards, exposures, and related health outcomes. The objective is to support policy strategies and interventions for disease prevention by communities and environmental health agencies at the federal, state, and local levels. The first 3 years of the initiative focused on supporting states and cities in developing capacity, information technology infrastructure, and pilot projects to demonstrate electronic linkage of environmental hazard or exposure data and disease data. The next phase requires implementation across states. This transition could provide opportunities to further integrate research, surveillance, and practice through attention to four areas. The first is to develop a shared and transparent knowledge base that draws on environmental health research and substantiates decisions about what to track and the interpretation of results. The second is to identify and address information needs of policy and stakeholder audiences in environmental health. The third is to adopt mechanisms for coordination, decision making, and governance that can incorporate and support the major entities involved. The fourth is to promote disease prevention by systematically identifying and addressing population-level environmental determinants of health and disease
Experimental Phase-equilibrium Constraints on the Phonolite Magmatic System of Erebus Volcano, Antarctica
International audienceField observations and petrological studies have recently advanced understanding of the magmatic system of Erebus volcano, renowned for its sustained CO2-rich degassing, and long-lived phonolitic lava lake. However, this body of work has highlighted uncertainty in several key parameters, including the magma temperature, redox state and the depth of the reservoir presumed to maintain the lava lake. Here, we use experimentally determined phase equilibria to constrain these unknowns. The experiments ranged in temperature from 900 to 1025°C, in pressure from atmospheric to 300 MPa, in water content from 0 to 8 wt %, and in oxygen fugacity from NNO + 4 (where NNO is nickel-nickel oxide) to QFM - 2 (where QFM is quartz-fayalite-magnetite). The natural system was experimentally reproduced at 950 ± 25°C, a pressure below 200 MPa, redox conditions between QFM and QFM - 1, and remarkably low water contents of less than 0*5 wt %. These findings help in understanding petrological observations, including melt inclusion data, as well as the measured composition of gas emissions from the lava lake. Biotite and amphibole appear in the crystallization sequence at around 925°C, even under very dry conditions (biotite). Both biotite and amphibole are absent in the phonolites erupted over the last 20 kyr at Erebus. The constant abundance of anorthoclase observed in the erupted lavas and bombs indicates that the shallow magmatic system feeding the Erebus lava lake (below pressures of 200 MPa) has been thermally buffered at 950 ± 25°C over this time period, possibly reflecting steady-state connection with the deep feeding system rooted in the mantle. Combined with recent seismological data, our results suggest that if a large phonolitic reservoir exists, then it should lie in the depth range 4-7*5 km. The tight constraints on temperature and redox conditions will be valuable for future thermodynamical and rheological modelling
Model-Based Air Flow Path Optimization for Heat Pump Clothes Dryer
A heat pump clothes dryer (HPCD) is an innovative appliance that uses a vapor compression system to dry clothes. Air circulates in a closed loop through the drum, so no vent is required. The condenser heats air to evaporate moisture out of the clothes, and the evaporator condenses water out of the air stream. As a result, the HPCD can achieve 50% energy savings compared to a conventional electric resistance dryer. We developed a physics-based, quasi-steady-state HPCD system model with detailed heat exchanger and compressor models. The system model is able to simulate the inherently transient HPCD drying process, to size components, and to reveal trends in key variables (e.g. compressor discharge temperature, power consumption, required drying time, etc.) The system model was calibrated using experimental data on a prototype HPCD. Air leakages, in and out, along the closed air circulation path of HPCD cause varied effects on the performance. Understanding the location, magnitude, and direction of air leakage of the heat pump clothes dryer is critical for accurately characterizing the performance and developing a high-performance design. The system model was used to reveal the impacts. In addition, model-based parametric optimizations were conducted to design the HPCD air path and leak points for optimum performance
Experimental Measurements of Clothes Dryer Drum Heat and Mass Transfer Effectiveness
Accurate system modeling of a clothes dryer requires a drum component that displays correct trends with respect to changing conditions. In this work, a model of drum heat and mass transfer effectiveness is adopted. Within this framework, experimental measurements of drum effectiveness are investigated with respect to several variables: drum volume, load mass, cloth type, drum volumetric air flow rate, and drum entering air temperature. These data can inform the modeling and simulation of any clothes dryer with horizontal-axis, axial-flow tumble-type clothes dryer drum
On bromine, nitrogen oxides and ozone depletion in the tropospheric plume of Erebus volcano (Antarctica)
International audienceSince the discovery of bromine oxide (BrO) in volcanic emissions, there has been speculation concerning its role in chemical evolution and notably ozone depletion in volcanic plumes. We report the first measurements using Differential Optical Absorption Spectroscopy (DOAS) of BrO in the tropospheric plume of the persistently degassing Erebus volcano (Antarctica). These are the first observations pertaining to emissions from an alkaline phonolitic magma. The observed BrO/SO2 ratio of 2.5 x 10-4 is similar to that measured at andesitic arc volcanoes. The high abundance of BrO is consistent with high abundances of F and Cl relative to sulfur in the Erebus plume. Our estimations of HBr flux and BrO production rate suggest that reactive bromine chemistry can explain a 35% loss of tropospheric O3 observed in the Erebus plume at approximately 30 km from source (Oppenheimer et al., 2010). Erebus also has a permanent lava lake, which could result in generation of NOx by thermal fixation of atmospheric N2 at the hot lava surface. Any NOx emission could play a potent role in reactive bromine chemistry. However, the presence of NO2 could not be detected in the plume, about 400 m above the lake, in our DOAS observations of 2005. Nor could we reproduce spectroscopic retrievals that reportedly identified NO2 in DOAS observations from 2003 made of the Erebus plume (Oppenheimer et al., 2005). Based on the NO2 detection limit of our analysis, we can state an upper limit of the NO2/SO2 ratio of †0.012, an order of magnitude lower than previously reported. Our new result supports a rapid oxidation of NOx in the young plume and is more consistent with measurements of NOy species measured using an instrumented aircraft flying in the plume. Model simulations, tuned for Erebus, were performed to reproduce the BrO/SO2 observed in the young plume and to investigate the impact of NOx emissions at source on the subsequent formation of BrO in the plume. They support our hypothesis of rapid conversion of NOx to NOy in the vicinity of the lava lake. This study thus places new constraints on the interaction between reactive nitrogen and bromine species in volcanic plumes, and its effects on ozone
CUI@CSCW: Collaborating through Conversational User Interfaces
This virtual workshop seeks to bring together the burgeoning communities centred on the design, development, application and study of so-called Conversational User Interfaces (CUIs). CUIs are used in myriad contexts, from online support chatbots through to entertainment devices in the home. In this workshop, we will examine the challenges involved in transforming CUIs into everyday computing devices capable of supporting collaborative activities across space and time. Additionally, this workshop seeks to establish a cohesive CUI community and research agenda within CSCW. We will examine the roles in which CSCW research can contribute insights into understanding how CUIs are or can be used in a variety of settings, from public to private, and how they can be brought into a potentially unlimited number of tasks. This proposed workshop will bring together researchers from academia and practitioners from industry to survey the state-of-the-art in terms of CUI design, use, and understanding, and will map new areas for work including addressing the technical, social, and ethical challenges that lay ahead. By bringing together existing researchers and new ideas in this space, we intend to foster a strong community and enable potential future collaborations
Hydrogen emissions from Erebus volcano, Antarctica
International audienceThe continuous measurement of molecular hydrogen (H2) emissions from passively degassing volcanoes has recently been made possible using a new generation of low-cost electrochemical sensors. We have used such sensors to measure H2, along with SO2, H2O and CO2, in the gas and aerosol plume emitted from the phonolite lava lake at Erebus volcano, Antarctica. The measurements were made at the crater rim between December 2010 and January 2011. Combined with measurements of the long-term SO2 emission rate for Erebus, they indicate a characteristic H2 flux of 0.03 kg s-1 (2.8 Mg day-1). The observed H2 content in the plume is consistent with previous estimates of redox conditions in the lava lake inferred from mineral compositions and the observed CO2/CO ratio in the gas plume (âŒ0.9 log units below the quartz-fayalite-magnetite buffer). These measurements suggest that H2 does not combust at the surface of the lake, and that H2 is kinetically inert in the gas/aerosol plume, retaining the signature of the high-temperature chemical equilibrium reached in the lava lake. We also observe a cyclical variation in the H2/SO2 ratio with a period of âŒ10 min. These cycles correspond to oscillatory patterns of surface motion of the lava lake that have been interpreted as signs of a pulsatory magma supply at the top of the magmatic conduit
Mantle to surface degassing of alkalic magmas at Erebus volcano, Antarctica
International audienceContinental intraplate volcanoes, such as Erebus volcano, Antarctica, are associated with extensional tectonics, mantle upwelling and high heat flow. Typically, erupted magmas are alkaline and rich in volatiles (especially CO2), inherited from low degrees of partial melting of mantle sources. We examine the degassing of the magmatic system at Erebus volcano using melt inclusion data and high temporal resolution open-path Fourier transform infrared (FTIR) spectroscopic measurements of gas emissions from the active lava lake. Remarkably different gas signatures are associated with passive and explosive gas emissions, representative of volatile contents and redox conditions that reveal contrasting shallow and deep degassing sources. We show that this unexpected degassing signature provides a unique probe for magma differentiation and transfer of CO2-rich oxidised fluids from the mantle to the surface, and evaluate how these processes operate in time and space. Extensive crystallisation driven by CO2 fluxing is responsible for isobaric fractionation of parental basanite magmas close to their source depth. Magma deeper than 4 kbar equilibrates under vapour-buffered conditions. At shallower depths, CO2-rich fluids accumulate and are then released either via convection-driven, open-system gas loss or as closed-system slugs that ascend and result in Strombolian eruptions in the lava lake. The open-system gases have a reduced state (below the QFM buffer) whereas the closed-system gases preserve their deep oxidised signatures (close to the NNO buffer)
A Nation-Wide Survey of High School Baseball Coachesâ Perceptions Indicates Their Arm Care Programs Play a Role in Injury Prevention
Background Arm care programs consisting of upper extremity strengthening and stretching have been recommended for injury prevention for pitchers of all ages. There has been no investigation into high school baseball coachesâ usage and perceptions of arm care programs to mitigate physical impairments associated with injuries in baseball players.
Hypothesis/Purpose The purpose of this study was to investigate the current usage of arm care programs by high school baseball coaches. The primary objective was to determine if coaches use group-based or individualized arm care programs. The secondary objective sought to determine if the use of arm care programs is influenced by coachesâ age, education, and experience level. Finally, this study explored the potential barriers to arm care implementation and high school baseball coachesâ current awareness and beliefs of injury prevention.
Study Design Descriptive cross-sectional survey
Methods A 29-item online survey was emailed to 18,500 high school baseball coaches throughout the United States. Data were collected for three months, and the response rate was 3.7%.
Results A total of 87.3% (n=571/654) of responding coaches use arm care programs with their players. Of coaches performing arm care, only 18.5% of 571 individualize their arm care exercises based on specific player needs. However, older and more experienced coaches are more likely to individualize their programs. Among the 12.7% (n=83/654) of coaches who do not use arm care programs, the two most commonly cited reasons for not implementing arm care were lack of observed benefit (41%) and insufficient staff (31%). Although 42% of 654 coaches recognized reduced shoulder mobility as a major contributor to injury, risk factors such as throwing with a fatigued arm, previous injury history, and throwing \u3e 8 months per year were not consistently identified as primary risk factors.
Conclusion The results of this study suggest that the majority high school baseball coaches implement group-based arm care exercise programs to prevent injury. Lack of confidence in the effectiveness and staffing limitations were major barriers to implementation of arm care programming. However, the responding coaches exhibited inconsistent risk factor awareness and dated injury prevention beliefs. Therefore, better educational collaboration between rehabilitation professionals and high school coaches regarding injury risk factors and preventative strategies is warranted.
Level of Evidence Level
Recovering the second moment of the strain distribution from neutron Bragg edge data
Point by point strain scanning is often used to map the residual stress
(strain) in engineering materials and components. However, the gauge volume and
hence spatial resolution is limited by the beam defining apertures and can be
anisotropic for very low and high diffraction (scattering) angles.
Alternatively, wavelength resolved neutron transmission imaging has a potential
to retrieve information tomographically about residual strain induced within
materials through measurement in transmission of Bragg edges - crystallographic
fingerprints whose locations and shapes depend on microstructure and strain
distribution. In such a case the spatial resolution is determined by the
geometrical blurring of the measurement setup and the detector point spread
function. Mathematically, reconstruction of strain tensor field is described by
the longitudinal ray transform; this transform has a non-trivial null-space,
making direct inversion impossible. A combination of the longitudinal ray
transform with physical constraints was used to reconstruct strain tensor
fields in convex objects. To relax physical constraints and generalise
reconstruction, a recently introduced concept of histogram tomography can be
employed. Histogram tomography relies on our ability to resolve the
distribution of strain in the beam direction, as we discuss in the paper. More
specifically, Bragg edge strain tomography requires extraction of the second
moment (variance about zero) of the strain distribution which has not yet been
demonstrated in practice. In this paper we verify experimentally that the
second moment can be reliably measured for a previously well characterised
aluminium ring and plug sample. We compare experimental measurements against
numerical calculation and further support our conclusions by rigorous
uncertainty quantification of the estimated mean and variance of the strain
distribution
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