340 research outputs found

    Sex Education: The Parent's Perspective

    Get PDF
    Presents summary findings from the first in-depth statewide poll of California parents on school-based comprehensive sex education

    Ports Sustainability: A life cycle assessment of Zero Emission Cargo Handling Equipment

    Get PDF
    The goal of this paper is to present and evaluate the latest trends in the cargo handling equipment (CHE) industry, aimed at mitigating the environmental impact of container terminal operations and contributing to the sustainability of ports. The most common machines for handling containers are described and dealt with separately, with a focus on electric CHE, usually referred to as 'zero emission' CHE. In a separate chapter, recommendations on methodologies suitable for investigation of the environmental footprint of CHE without on-site measuring are reviewed. The life cycle assessment (LCA) methodology as a tool for comparison of conventional and 'zero emission' technology is emphasised with examples. The conventional diesel rubber-tired gantry (RTG) crane and utility tractor rig (UTR) are compared with an electric RTG and UTR using an LCA approach

    Sexually Transmitted Infections Among California Youth: Estimated Incidence and Direct Medical Cost, 2005

    Get PDF
    Purpose: The purpose of this study was to estimate the incidence and the direct medical cost of sexually transmitted infections (STIs) among young persons in California and each of its 58 counties, and to better inform discussions about statewide policies and local resources needed for STI prevention and control efforts. Methods: On the basis of the methods developed at the Centers for Disease Control and Prevention we estimated the statewide number of new cases of eight major STIs among young persons aged 15 to 24 years in California in 2005: chlamydia, gonorrhea, syphilis, genital herpes, human papillomavirus (HPV), hepatitis B, trichomoniasis, and HIV. We also calculated the direct medical cost of these STIs using national cost-per-case estimates. To inform local policy discussions about STI control efforts, the statewide estimates were allocated by county. Results: An estimated 1.1 million new cases of STIs occurred among young persons in California in 2005, with a direct medical cost of 1.1billion.Theestimatednumberofnewcaseswithincountiesrangedfromalowof82inAlpineandSierracounties,atacostof1.1 billion. The estimated number of new cases within counties ranged from a low of 82 in Alpine and Sierra counties, at a cost of 38,000, to a high of about 360,000 in Los Angeles County, at a cost of $390 million. Conclusions: These estimates illustrate the widespread and frequently underreported incidence and costs of youth STIs in California and its counties, and provide the foundation for a comprehensive assessment of youth STI prevention needs

    Unveiling the Mysteries of Mars with a Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM)

    Get PDF
    Development of a miniaturized scanning electron microscope that will utilize the martian atmosphere to dissipate charge during analysis continues. This instrument is expected to be used on a future rover or lander to answer fundamental Mars science questions. To identify the most important questions, a survey was taken at the 47th Lunar and Planetary Science Conference (LPSC). From the gathered information initial topics were identified for a SEM on the martian surface. These priorities are identified and discussed below. Additionally, a concept of operations is provided with the goal of maximizing the science obtained with the minimum amount of communication with the instrument

    Simulation and Characterization of a Miniaturized Scanning Electron Microscope

    Get PDF
    A miniaturized Scanning Electron Microscope (mSEM) for in-situ lunar investigations is being developed at NASA Marshall Space Flight Center with colleagues from the University of Alabama in Huntsville (UAH), Advanced Research Systems (ARS), the University of Tennessee in Knoxville (UTK) and Case Western Reserve University (CWRU). This effort focuses on the characterization of individual components of the mSEM and simulation of the complete system. SEMs can provide information on the size, shape, morphology and chemical composition of lunar regolith. Understanding these basic properties will allow us to better estimate the challenges associated with In-Situ Resource Utilization and to improve our basic science knowledge of the lunar surface (either precluding the need for sample return or allowing differentiation of unique samples to be returned to Earth.) The main components of the mSEM prototype includes: a cold field emission electron gun (CFEG), focusing lens, deflection/scanning system and backscatter electron detector. Of these, the electron gun development is of particular importance as it dictates much of the design of the remaining components. A CFEG was chosen for use with the lunar mSEM as its emission does not depend on heating of the tungsten emitter (lower power), it offers a long operation lifetime, is orders of magnitude brighter than tungsten hairpin guns, has a small source size and exhibits low beam energy spread

    Interpreting COVID-19 Deaths among Nursing Home Residents in the US: The Changing Role of Facility Quality over Time

    Get PDF
    A report published last year by the Centers for Medicare & Medicaid Services (CMS) highlighted that COVID-19 case counts are more likely to be high in lower quality nursing homes than in higher quality ones. Since then, multiple studies have examined this association with a handful also exploring the role of facility quality in explaining resident deaths from the virus. Despite this wide interest, no previous study has investigated how the relation between quality and COVID-19 mortality among nursing home residents may have changed, if at all, over the progression of the pandemic. This understanding is indeed lacking given that prior studies are either cross-sectional or are analyses limited to one specific state or region of the country. To address this gap, we analyzed changes in nursing home resident deaths across the US between June 1, 2020 and January 31, 2021 (n = 12,415 nursing homes X 8 months) using both descriptive and multivariable statistics. We merged publicly available data from multiple federal agencies with mortality rate (per 100,000 residents) as the outcome and CMS 5-star quality rating as the primary explanatory variable of interest. Covariates, based on the prior literature, consisted of both facility- and community-level characteristics. Findings from our secondary analysis provide robust evidence of the association between nursing home quality and resident deaths due to the virus diminishing over time. In connection, we discuss plausible reasons, especially duration of staff shortages, that over time might have played a critical role in driving the quality-mortality convergence across nursing homes in the US

    Directional Solidification of Mercury Cadmium Telluride During the Second United States Microgravity Payload Mission (USMP-2)

    Get PDF
    As a solid solution semiconductor having, a large separation between liquidus and solidus, mercury cadmium telluride (MCT) presents a formidable challenge to crystal growers desiring an alloy of high compositional uniformity. To avoid constitutional supercooling during Bridgman crystal growth it is necessary to solidify slowly in a high temperature gradient region. The necessary translation rate of less than 1 mm/hr results in a situation where fluid flow induced by gravity on earth is a significant factor in material transport. The Advanced Automated Directional Solidification Furnace (AADSF) is equipped to provide the stable thermal environment with a high gradient, and the required slow translation rate needed. Ground based experiments in AADSF show clearly the dominance of flow driven transport. The first flight of AADSF in low gravity on USMP-2 provided an opportunity to test theories of fluid flow in MCT and showed several solidification regimes which are very different from those observed on earth. Residual acceleration vectors in the orbiter during the mission were measured by the Orbital Acceleration Research Experiment (OARE), and correlated well with observed compositional differences in the samples

    A Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM) for In-Situ Mars Surface Sample Analysis

    Get PDF
    The Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM) project, funded by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Research Opportunities in Space and Earth Sciences (ROSES), will build upon previous miniaturized SEM designs and recent advancements in variable pressure SEM's to design and build a SEM to complete analyses of samples on the surface of Mars using the atmosphere as an imaging medium. This project is a collaboration between NASA Marshall Space Flight Center (MSFC), the Jet Propulsion Laboratory (JPL), electron gun and optics manufacturer Applied Physics Technologies, and small vacuum system manufacturer Creare. Dr. Ralph Harvery and environmental SEM (ESEM) inventor Dr. Gerry Danilatos serve as advisors to the team. Variable pressure SEMs allow for fine (nm-scale) resolution imaging and micron-scale chemical study of materials without sample preparation (e.g., carbon or gold coating). Charging of a sample is reduced or eliminated by the gas surrounding the sample. It is this property of ESEMs that make them ideal for locations where sample preparation is not yet feasible, such as the surface of Mars. In addition, the lack of sample preparation needed here will simplify the sample acquisition process and allow caching of the samples for future complementary payload use

    Aneurysm Identification in Cerebral Models with Multiview Convolutional Neural Network

    Get PDF
    Stroke is the third most common cause of death and a major contributor to long-term disability worldwide. Severe stroke is most often caused by the rupture of a cerebral aneurysm, a weakened area in a blood vessel. The detection and quantification of cerebral aneurysms are essential for the prevention and treatment of aneurysmal rupture and cerebral infarction. Here, we propose a novel aneurysm detection method in a three-dimensional (3D) cerebrovascular model based on convolutional neural networks (CNNs). The multiview method is used to obtain a sequence of 2D images on the cerebral vessel branch model. The pretrained CNN is used with transfer learning to overcome the small training sample problem. The data augmentation strategy with rotation, mirroring and flipping helps improve the performance dramatically, particularly on our small datasets. The hyperparameter of the view number is determined in the task. We have applied the labeling task on 56 3D mesh models with aneurysms (positive) and 65 models without aneurysms (negative). The average accuracy of individual projected images is 87.86%, while that of the model is 93.4% with the best view number. The framework is highly effective with quick training efficiency that can be widely extended to detect other organ anomalies
    corecore