Potential inhibitors and sources of error in the measurement of travertine precipitation rates in a karst stream influenced by thermal mineral waters

Precipitation rates for travertine have been studied in many natural settings and compared to theoretical calcite (CaCO3) precipitation rates; in most studies, the emphasis is placed on the degassing of CO 2 as the primary controlling mechanism. Little research has been done in natural settings to evaluate precipitate composition, rates of precipitation, and the role of potential inhibitors of calcite growth. This study addresses these questions in a Sweet Springs Creek, West Virginia-Virginia: a karst stream fed partly by thermal mineral waters with high CO2. For this study, travertine plates were deployed to measure the accretion of precipitates in the presence of natural inhibitors. The mass change on the plates was interpreted as calcite precipitate and converted to precipitation rates by accounting for the plates\u27 length of time in-situ. The Plummer-Wigley-Pinkhurst calcite precipitation rate equation was used to estimate calcite precipitation rates based on bulk water chemistry and compared to the measured plate rates, which were on average one order-of-magnitude lower. SEM-EDS analysis of the mineral precipitate on the travertine plates showed extensive biological activity which correlated with sites with higher variability between calculated and observed precipitation rates. Analysis of precipitate with XRF-Fusion found that \u3e10% of the mass in some samples was not calcite. Gypsum selenite (CaSO 4˙2H2O) crystals were found in addition to detrital quartz on plates surfaces as well, suggesting non-calcite mineral precipitation significant enough to introduce error into estimates. These results suggest that further evaluation of mineral precipitates is needed in order to accurately gauge true precipitation rates in-situ and that previous studies likely underestimated the difference between estimated and actual precipitation rates

Self-Balancing, Optical-Center-Pivot, Fast-Steering Mirror

A complete, self-contained fast-steering- mirror (FSM) mechanism is reported consisting of a housing, a mirror and mirror-mounting cell, three PZT (piezoelectric) actuators, and a counterbalance mass. Basically, it is a comparatively stiff, two-axis (tip-tilt), self-balanced FSM. The present invention requires only three (or three pairs for flight redundancy) actuators. If a PZT actuator degrades, the inherent balance remains, and compensation for degraded stroke is made by simply increasing the voltage to the PZT. Prior designs typically do not pivot at the mirror optical center, creating unacceptable beam shear

A qualitative investigation into the management of diabetic learners in South African schools

Submitted in fulfillment for the requirement of the degree of Master of Education in the School of Education, Faculty of Humanities, University of the Witwatersrand 3 March 2014This research was sparked by a personal encounter with diabetes. My middle child was first diagnosed with type 1 diabetes mellitus (diabetes) four years ago. None of his teachers had any idea of how to assist us as parents in the daily management of this disease. The purpose of this investigation then, began initially with this background in mind in an attempt to discover how the management of diabetes occurs in public schools across South Africa. Literature indicates that there is apparent widespread screening to detect the symptoms and the onset of diabetes in other countries across the world which reveals that both type 1 and type 2diabetes are on the increase. The respondents in the research process consisted of principals, teachers, peers of the diabetic learners and the diabetics themselves. The investigative process required the respondents to complete a questionnaire as well as being part of an interview process to determine the major outcomes of the study. These interviews were audiotaped. The outcomes of the investigative process included examining the daily routines of the diabetic. The results of the investigation revealed that in the context of the South African situation concerning learners suffering from diabetes, basic knowledge about the disease is limited to the extent that teachers and peers of the diabetic learner are ill-informed and this is as a result of a lack of communication in the entirety of the management process of diabetic learners at schools in this country. Diabetes is generally a “mystery” to most people not in contact with it on a daily basis and many people are confused by the glucose monitoring and the insulin injecting process as a “foreign method” of medicine. The results of the investigative study indicate that diabetic children need to have a management plan for school but significantly more important is the assistance, understanding and communication that is required on a daily basis by a team of caregivers consisting of parents, educators and their peers if diabetics are to feel and form part of an integrated South African education system. Also, the study reveals that the training of certain individuals to take specific care of diabetics would assist these children. Camps that diabetics can attend also assist their child in taking most of the responsibility for their own lives and the diabetic groups that parents can join to share similar experiences with other adults also proved effective in the practice of sound management. For diabetics, friendships fostered and the “buddy” system in the classroom where a friend could identify dangerous situations proved invaluable. Policy makers need also to heed the call of re-visiting policy decisions of the past in order to serve the plight of the diabetic learner and increase the awareness of diabetes in our schools

Am I getting an accurate picture: A tool to assess clinical handover in remote settings?

Background: Good clinical handover is critical to safe medical care. Little research has investigated handover in rural settings. In a remote setting where nurses and medical students give telephone handover to an aeromedical retrieval service, we developed a tool by which the receiving clinician might assess the handover; and investigated factors impacting on the reliability and validity of that assessment. Methods: Researchers consulted with clinicians to develop an assessment tool, based on the ISBAR handover framework, combining validity evidence and the existing literature. The tool was applied 'live' by receiving clinicians and from recorded handovers by academic assessors. The tool's performance was analysed using generalisability theory. Receiving clinicians and assessors provided feedback. Results: Reliability for assessing a call was good (G = 0.73 with 4 assessments). The scale had a single factor structure with good internal consistency (Cronbach's alpha = 0.8). The group mean for the global score for nurses and students was 2.30 (SD 0.85) out of a maximum 3.0, with no difference between these sub-groups. Conclusions: We have developed and evaluated a tool to assess high-stakes handover in a remote setting. It showed good reliability and was easy for working clinicians to use. Further investigation and use is warranted beyond this setting

TASK HANDOFF BETWEEN HUMANS AND AUTOMATION

The Department of Defense (DOD) seeks to incorporate human-automation teaming to decrease human operators’ cognitive workload, especially in the context of future vertical lift (FVL). Researchers created a “wizard of oz” study to observe human behavior changes as task difficulty and levels of automation increased. The platform used for the study was a firefighting strategy software game called C3Fire. Participants were paired with a confederate acting as an automated agent to observe the participant’s behavior in a human-automation team. The independent variables were automation level (within; low, medium, high) and queuing (between; uncued, cued). The dependent variables were the number of messages transmitted to the confederate, the number of tasks embedded in those messages (tasks handed off), and the participant’s self-reported cognitive workload score. The study results indicated that as the confederate increased its scripted level of automation, the number of tasks handed off to automation increased. However, the number of messages transmitted to automation and the subjective cognitive workload remained the same. The study’s findings suggest that while human operators were able to bundle tasks, cognitive workload remained relatively unchanged. The results imply that the automation level may have less impact on cognitive workload than anticipated.Major, United States ArmyCaptain, United States ArmyCaptain, United States ArmyCaptain, United States ArmyCaptain, United States ArmyApproved for public release. Distribution is unlimited

A51F-0123: Model Analysis of Tropospheric Aerosol Variability and Sources over the North Atlantic During NAAMES 2015-2016

The North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) is a five-year Earth-Venture Suborbital-2 Mission to characterize the plankton ecosystems and their influences on remote marine aerosols, boundary layer clouds, and their implications for climate in the North Atlantic. While marine-sourced aerosols have been shown to make important contributions to surface aerosol loading, cloud condensation nuclei and ice nuclei concentrations over remote marine and coastal regions, it is still a challenge to differentiate the marine biogenic aerosol signal from the strong influence of continental pollution outflow. We examine here the spatiotemporal variability and quantify the sources of tropospheric aerosols over the North Atlantic during the first two phases (November 2015 and May-June 2016) of NAAMES using a state-of-the-art chemical transport model (GEOS-Chem). The model is driven by the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) from the NASA Global Modeling and Assimilation Office (GMAO). It includes sulfate-nitrate-ammonium aerosol thermodynamics coupled to ozone-NOx-hydrocarbon-aerosol chemistry, mineral dust, sea salt, elemental and organic carbon aerosols, and especially a recently implemented parameterization for the marine primary organic aerosol emission. The simulated aerosols over the North Atlantic are evaluated with available satellite (e.g., MODIS) observations of aerosol optical depths (AOD), and aircraft and ship aerosol measurements. We diagnose transport pathways for continental pollution outflow over the North Atlantic using carbon monoxide, an excellent tracer for anthropogenic pollution transport. We also conduct model perturbation experiments to quantify the relative contributions of terrestrial and oceanic sources to the aerosol loading, AOD, and their variability over the North Atlantic

Bisphenol F affects neurodevelopmental gene expression, mushroom body development, and behavior in Drosophila melanogaster

Bisphenol F (BPF) is a potential neurotoxicant used as a replacement for bisphenol A (BPA) in polycarbonate plastics and epoxy resins. We investigated the neurodevelopmental impacts of BPF exposure using Drosophila melanogaster as a model. Our transcriptomic analysis indicated that developmental exposure to BPF caused the downregulation of neurodevelopmentally relevant genes, including those associated with synapse formation and neuronal projection. To investigate the functional outcome of BPF exposure, we evaluated neurodevelopmental impacts across two genetic strains of Drosophila— w1118 (control) and the Fragile X Syndrome (FXS) model—by examining both behavioral and neuronal phenotypes. We found that BPF exposure in w1118 Drosophila caused hypoactive larval locomotor activity, decreased time spent grooming by adults, reduced courtship activity, and increased the severity but not frequency of β-lobe midline crossing defects by axons in the mushroom body. In contrast, although BPF reduced peristaltic contractions in FXS larvae, it had no impact on other larval locomotor phenotypes, grooming activity, or courtship activity. Strikingly, BPF exposure reduced both the severity and frequency of β-lobe midline crossing defects in the mushroom body of FXS flies, a phenotype previously observed in FXS flies exposed to BPA. This data indicates that BPF can affect neurodevelopment and its impacts vary depending on genetic background. Further, BPF may elicit a gene-environment interaction with Drosophila fragile X messenger ribonucleoprotein 1 (dFmr1)—the ortholog of human FMR1, which causes fragile X syndrome and is the most common monogenetic cause of intellectual disability and autism spectrum disorder

Cold Atom Space Payload Atmospheric Drag Mission (CASPA-ADM)

To gain better understanding of the upper atmospheric dynamics requires more accurate determination of the mass density distribution in the thermosphere. Improved measurements of drag, by means of satellite accelerometery, can be used to more precisely determine this distribution. In addition, atmospheric drag in Low Earth Orbit (LEO) is particularly of interest for climate modelling, weather forecasting and satellite orbit prediction. RAL Space, Teledyne-e2v and the University of Birmingham are developing a Cold Atom Space Payload Atmospheric Drag Mission (CASPA-ADM). The aim of the project, supported by the UK Centre for Earth Observation Instrumentation (CEOI), is to develop a technology demonstrator based on Cold Atom Interferometry (CAI) to take sensitive measurements of atmospheric drag. The underlying CAI technology has been previously flown on the Chinese Space Station, the International Space Station, and in sounding rockets. However, it has not yet been used as the fundamental sensor technology in a free flight space mission. The team is producing a space-suitable accelerometer that can be embedded in small satellites such as 16U CubeSats and are addressing the engineering challenges associated with space qualification and miniaturisation, while keeping the performance level of systems with larger Size, Weight and Power (SWaP)

Multi-campaign Ship and Aircraft Observations of Marine Cloud Condensation Nuclei and Droplet Concentrations

In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates