4,181 research outputs found
Noncontact GMR measurements of synthetic spin valves using IR reflection spectroscopy
The magnetorefractive effect has been used in infrared reflection spectroscopy to study the magnetotransport properties of synthetic spin valves. This optical noncontact technique shows excellent correlation with the electrical giant magnetoresistance data
Resonance Production in STAR
The recent results from resonance production in central Au+Au and p+p
collisions at 200 GeV from the STAR experiment at RHIC
are presented and discussed.Comment: 7 pages, proceedings 19th Winter Workshop on Nuclear Dynamics,
Breckenridge, Colorado, USA, February 8-15, 200
Citizen science and crowdsourced data collection, not government statistics, provide the most reliable count of citizen fatalities by police
In 2016 one thousand ninety-two civilians were killed by the police in the United States. When civilians die during police encounters they lose not only their right to due process, but also their chance to be counted. Matthew J. Thompson and Chris M. Smith argue that since the fatal police shooting of Michael Brown in August 2014, more is known about fatal police violence than ever before due to an increase not in official government statistics but in citizen crowdsourced data collection
African American Adults’ Experiences with the Health Care System: In Their Own Words
African Americans suffer a disproportionate burden of death and illness from a number of different chronic diseases. Inequalities in health care practices and poor patient and provider communication between African American patients and health care professionals contribute to these disparities. We describe findings from focus groups with 79 urban African Americans in which the participants discussed their interactions with the healthcare system as well as beliefs and opinions of the healthcare system and professionals. Analysis revealed five major themes: (1) historical and contextual foundations; (2) interpersonal experiences with physicians and other health care workers; (3) discrimination; (4) trust, opinions and attitudes, and (5) improving health care experiences. These findings indicate that perceptions of discrimination and racism were prevalent among African Americans in this study, and that the expectation of a negative interaction is a barrier to seeking care. Authors discuss prevention and public health implications of these findings and make recommendations for health care practitioners
Semi-automated image analysis for the identification of bivalve larvae from a Cape Cod estuary
Author Posting. © Association for the Sciences of Limnology and Oceanography, 2012. This article is posted here by permission of Association for the Sciences of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography: Methods 10 (2012): 538-554, doi:10.4319/lom.2012.10.538.Machine-learning methods for identifying planktonic organisms are becoming well-established. Although similar morphologies among species make traditional image identification methods difficult for larval bivalves, species-specific shell birefringence patterns under polarized light permit identification by color and texture-based features. This approach uses cross-polarized images of bivalve larvae, extracts Gabor and color angle features from each image, and classifies images using a Support Vector Machine. We adapted this method, which was established on hatchery-reared larvae, to identify bivalve larvae from a series of field samples from a Cape Cod estuary in 2009. This method had 98% identification accuracy for four hatchery-reared species. We used a multiplex polymerase chain reaction (PCR) method to confirm field identifications and to compare accuracies to the software classifications. Image classification of larvae collected in the field had lower accuracies than both the classification of hatchery species and PCR-based identification due to error in visually classifying unknown larvae and variability in larval images from the field. A six-species field training set had the best correspondence to our visual classifications with 75% overall agreement and individual species agreements from 63% to 88%. Larval abundance estimates for a time-series of field samples showed good correspondence with visual methods after correction. Overall, this approach represents a cost- and time-saving alternative to molecular-based identifications and can produce sufficient results to address long-term abundance and transport-based questions on a species-specific level, a rarity in studies of bivalve larvae.This project was supported by an award to S. Gallager
and C. Mingione Thompson from the Estuarine Reserves Division, Office
of Ocean and Coastal Resource Management, National Ocean Service,
National Oceanic and Atmospheric Administration and a grant from
Woods Hole Oceanographic Institution’s Coastal Ocean Institute
Atlantic Ocean Heat Transport Enabled by Indo-Pacific Heat Uptake and Mixing
The ocean transports vast amounts of heat around the planet, helping to regulate regional climate. One important component of this heat transport is the movement of warm water from equatorial regions toward the poles, with colder water flowing in return. Here, we introduce a framework relating meridional heat transport to the diabatic processes of surface forcing and turbulent mixing that move heat across temperature classes. Applied to a (1/4)° global ocean model the framework highlights the role of the tropical Indo‐Pacific in the global ocean heat transport. A large fraction of the northward heat transport in the Atlantic is ultimately sourced from heat uptake in the eastern tropical Pacific. Turbulent mixing moves heat from the warm, shallow Indo‐Pacific circulation to the cold deeper‐reaching Atlantic circulation. Our results underscore a renewed focus on the tropical oceans and their role in global circulation pathways
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State Quality-Adjusted Life Expectancy for U.S. adults from 1993 to 2008
Purpose:
Quality-Adjusted Life Expectancy (QALE) is a summary measure of mortality and health-related quality of life (HRQOL) across different stages of life. This study developed a method to calculate state-level QALE for U.S. adults.
Methods:
Population HRQOL data came from the Behavioral Risk Factor Surveillance System (BRFSS). Using age-specific deaths from the Mortality Summary File, this study constructed life tables to estimate life expectancy and QALE for all 50 States and the District of Columbia by sex and race from 1993 through 2008.
Results:
From 1993 to 2008, the QALE of an U.S. adult at 18 years old had increased from 51.2 to 52.3 years. In 2006, states with the highest QALE were Hawaii (56.2), Minnesota (55.2), North Dakota (54.9), Iowa (54.7), and Nebraska (54.4), while the states with the lowest QALE were West Virginia (47.1), Mississippi (48.2), Alabama (48.5), Kentucky (48.5), and Oklahoma (49.0).
Conclusions:
Because population HRQOL values and mortality statistics are available from existing and publicly accessible data and because formulas for the calculation of QALE and its standard error are easy to incorporate in a spreadsheet, State and local Health Departments can calculate QALE as a routine surveillance measurement for tracking their population’s health over time
Mitigating source water risks with improved wildfire containment
Includes bibliographical references (pages 20-25).In many fire-prone watersheds, wildfire threatens surface drinking water sources with eroded contaminants. We evaluated the potential to mitigate the risk of degraded water quality by limiting fire sizes and contaminant loads with a containment network of manager-developed Potential fire Operational Delineations (PODs) using wildfire risk transmission methods to partition the effects of stochastically simulated wildfires to within and out of POD burning. We assessed water impacts with two metrics—total sediment load and frequency of exceeding turbidity limits for treatment—using a linked fire-erosion-sediment transport model. We found that improved fire containment could reduce wildfire risk to the water source by 13.0 to 55.3% depending on impact measure and post-fire rainfall. Containment based on PODs had greater potential in our study system to reduce total sediment load than it did to avoid degraded water quality. After containment, most turbidity exceedances originated from less than 20% of the PODs, suggesting strategic investments to further compartmentalize these areas could improve the effectiveness of the containment network. Similarly, risk transmission varied across the POD boundaries, indicating that efforts to increase containment probability with fuels reduction would have a disproportionate effect if prioritized along high transmission boundaries
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