7,343 research outputs found
A Miniaturized Laser Heterodyne Radiometer for Greenhouse Gas Measurements in the Atmospheric Column
Laser Heterodyne Radiometry is a technique adapted from radio receiver technology has been used to measure trace gases in the atmosphere since the 1960s.By leveraging advances in the telecommunications industry, it has been possible to miniaturize this technology.The mini-LHR (Miniaturized Laser Heterodyne Radiometer) has been under development at NASA Goddard Space flight Center since 2009. This sun-viewing instrument measures carbon dioxide and methane in the atmospheric column and operates in tandem with an AERONET sun photometer producing a simultaneous measure of aerosols. The mini-LHR has been extensively field tested in a range of locations ranging in the continental US as well as Alaska and Hawaii and now operates autonomously with sensitivities of approximately 0.2 ppmv and approximately10 ppbv, for carbon dioxide and methane respectively, for 10 averaged scans under clear sky conditions
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Identifying Opportunities for Collaboration Across the Social Sciences to Reach the 10-10-10: A Multilevel Approach.
BACKGROUND:The national and global strategy to combat HIV, often referred to as the "90-90-90," aims to diagnose 90% of people living with HIV, get 90% of those diagnosed onto antiretroviral treatment (ART), and achieve viral suppression in 90% of those on ART. The remaining 10-10-10 who will be undiagnosed, not on ART, or not virally suppressed, include vulnerable persons and populations most affected by social determinants of health. Given their foci on the social determinants of health at the individual, social, and structural levels, social scientists are in a prime position to help reach the 10-10-10. A potentially effective way for social scientists to achieve this goal is to examine the issues that affect the 10-10-10 using a multilevel framework, to understand at what levels their own approaches fit within such a multilevel framework, and to seek intentional collaborations with other social scientists who may work at different levels but whose approaches may complement their own within multilevel collaborations. APPROACH:The present article describes how a multilevel framework can guide collaboration across disciplines within the social sciences toward the common goal of reaching the 10-10-10. CONCLUSIONS:Within a multilevel framework, social scientists can work collaboratively to address the needs of individuals among the 10-10-10 within the social and structural contexts (eg, social norms, stigma, poverty, and barriers to care) that affect their health. Such an approach draws on the unique strengths and approaches of different social-science disciplines while also building capacity for individuals most affected by social determinants of health
“Happy Housewives”: Sisters in the Struggle for Women’s Rights
Kirmser Undergraduate Research Award - Individual Non-Freshman, honorable mentionCitation: Wilson, E. (2016). “Happy Housewives”: Sisters in the Struggle for Women’s Rights. Unpublished manuscript, Kansas State University, Manhattan, KS.Dr. Charles Sanders““Happy Housewives”: Sisters in the Struggle for Women’s Rights” discusses social advancement from the perspective of an often unacknowledged group of people, the domestic and motherly “happy housewives”, who played a unique and unexpectedly important role in the progress of the Women’s Rights Movement in the 19th century. This paper argues that the women who prescribed to the ideology of separate spheres—that man had his place in society and woman had hers in the home—though often belittled, were essential to the progress of the Women’s Rights Movement. While outspoken suffragettes paraded the streets and outwardly protested for women’s rights, the “happy housewives” expanded women’s influence and societal distinction in subtle but significant ways that changed women’s role in the United States forever. Primary sources that support this claim include personal accounts and letters from “happy housewives”, sermons on the subject of women’s role in society, articles published in ladies’ magazines by and for the “happy housewives”, speeches, newspaper publications, cookbooks, and teachers’ guides
Livermore's Cube Satellite Evolution: Space Program Innovation: One Small Satellite at a Time
Cube satellites, called CubeSats, are a common type of nanosatellite comprising a modular framework of cube-shaped building block units that measure 10 centimeters per side. Their lower cost and ease of construction compared to large, conventional satellites have made them a popular choice for modern space applications. Lawrence Livermores first involvement with CubeSats began nearly a decade ago when scientists developed optical imaging payloads for the Space-Based Telescopes for the Actionable Refinement of Ephemeris project to monitor space debris. More recently, as part of a collaboration with NASA Goddard Space Flight Center, the Laboratory has helped develop the MiniCarb CubeSat for measuring atmospheric greenhouse gases. MiniCarb will be the first to use the innovative, Laboratory-developed CubeSat Next Generation Bus platform, ushering in a new era for the institutions Space Science and Security Program
Intersectional Discrimination Is Associated with Housing Instability among Trans Women Living in the San Francisco Bay Area.
Trans women face numerous structural barriers to health due to discrimination. Housing instability is an important structural determinant of poor health outcomes among trans women. The purpose of this study was to determine if experiences of intersectional anti-trans and racial discrimination are associated with poor housing outcomes among trans women in the San Francisco Bay Area. A secondary analysis of baseline data from the Trans *National study (n = 629) at the San Francisco Department of Public Health (2016-2018) was conducted. Multivariable logistic regression was used to analyze the association between discrimination as an ordered categorical variable (zero, one to two, or three or more experiences) and housing status adjusting for age, years lived in the Bay Area, and gender identity. We found that the odds of housing instability increased by 1.25 for every categorical unit increase (1-2, or 3+) in reported experiences of intersectional (both anti-trans and racial) discrimination for trans women (95% CI = 1.01-1.54, p-value < 0.05). Intersectional anti-trans and racial discrimination is associated with increased housing instability among trans women, giving some insight that policies and programs are needed to identify and address racism and anti-trans stigma towards trans women. Efforts to address intersectional discrimination may positively impact housing stability, with potential for ancillary effects on increasing the health and wellness of trans women who face multiple disparities
Miniaturized Gas Correlation Radiometer for the Detection of Trace Gases in the Martian Atmosphere
We present a miniaturized and simplified version of a gas correlation radiometer (GCR) capable of simultaneously mapping multiple trace gases and identifying active regions on the Mars surface. Gas correlation radiometry (GCR) has been shown to be a sensitive and versatile method for detecting trace gases in Earth's atmosphere. Reduction of the size and mass of the GCR was achieved by implementing compact, light-weight 1 mm inner diameter hollow-core optical fibers (hollow waveguides) as the gas correlation cells. In a comparison with an Earth orbiting CO2 GCR instrument, exchanging the 10 m multipass cells with hollow waveguide gas correlation cells of equivalent path length reduces the mass from approximately 150 kg to approximately 0.5 kg, and reduces the volume from 1.9 m x 1.3 m x 0.86 m to a small bundle of fiber coils approximately 1 meter in diameter by 0.05 m in height (mass and volume reductions of greater than 99%). A unique feature of this instrument is its stackable module design, with a single module for each trace gas. Each of the modules is self-contained, and fundamentally identical; differing by the bandpass filter wavelength range and gas mixtures inside the hollow-waveguide absorption cells. The current configuration contains four stacked modules for simultaneous measurements of methane (CH4), formaldehyde (H2CO), water vapor (H2O), and deuterated water vapor (HDO) but could easily be expanded to include measurements of additional species of interest including nitrous oxide (N2O), hydrogen sulfide (H2S), methanol (CH3OH), and sulfur dioxide (SO2), as well as carbon dioxide (CO2) for a simultaneous measure of mass balance. Preliminary results indicate that a 1 ppb detection limit is possible for both formaldehyde and methane with one second of averaging. Using non-optimized components, we have demonstrated an instrument sensitivity equivalent to approximately 30 ppb for formaldehyde, and approximately 500 ppb for methane. We expect custom bandpass filters and 6 m long waveguides to significantly improve these promising results. Ongoing testing is being conducted on water vapor and deuterated water vapor
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