417 research outputs found
High and low threshold P-channel metal oxide semiconductor process and description of microelectronics facility
The fabrication techniques and detail procedures for creating P-channel Metal-Oxide-Semiconductor (P-MOS) integrated circuits at George C. Marshall Space Flight Center (MSFC) are described. Examples of P-MOS integrated circuits fabricated at MSFC together with functional descriptions of each are given. Typical electrical characteristics of high and low threshold P-MOS discrete devices under given conditions are provided. A general description of MSFC design, mask making, packaging, and testing procedures is included. The capabilities described in this report are being utilized in: (1) research and development of new technology, (2) education of individuals in the various disciplines and technologies of the field of microelectronics, and (3) fabrication of many types of specially designed integrated circuits which are not commercially feasible in small quantities for in-house research and development programs
Multilevel metallization method for fabricating a metal oxide semiconductor device
An improved method is described of constructing a metal oxide semiconductor device having multiple layers of metal deposited by dc magnetron sputtering at low dc voltages and low substrate temperatures. The method provides multilevel interconnections and cross over between individual circuit elements in integrated circuits without significantly reducing the reliability or seriously affecting the yield
The MSFC complementary metal oxide semiconductor (including multilevel interconnect metallization) process handbook
The fabrication techniques for creation of complementary metal oxide semiconductor integrated circuits at George C. Marshall Space Flight Center are described. Examples of C-MOS integrated circuits manufactured at MSFC are presented with functional descriptions of each. Typical electrical characteristics of both p-channel metal oxide semiconductor and n-channel metal oxide semiconductor discrete devices under given conditions are provided. Procedures design, mask making, packaging, and testing are included
Winter and Spring Water Quality of the Big Creek Watershed, Craighead County, Arkansas: Nutrients, Habitat, and Macroinvertebrates
The objective of this study was to assess the water quality of the Big Creek watershed during the winter and spring of 2002 by analyzing water physical, chemical variables, aquatic macro-invertebrates, and habitat. The Big Creek watershed, arising on Crowley\u27s Ridge in northeast Arkansas, is a small deltaic watershed and is an area of intense cultivation. Four stations, Big Creek Upper (BCU), Mud Creek (MC),Lost Creek (LC), and Big Creek Lower (BCL) were established for this study from Big Creek, Mud Creek and Lost Creek. Water samples were collected on a weekly basis for 10 weeks from January 2002 through March 2002. We analyzed these streams for temperature, pH, D.O., conductivity, TSS, chlorophyll- a, DOC, total N and P, total dissolved N and P, nitrate, ammonium, and soluble reactive phosphorus. During this time period, we also sampled aquatic macroinvertebrates and assessed stream habitat according to USEPA rapid bioassessment protocols. Overall, nutrients and TSS were high, pH fluctuated from 5.8 to 7.8, and D.O. was moderate to high, ranging from 6.75 to 13.24 mg/L. Generally, physical and chemical water variables were correlated with changes in stream discharge. For a 20-jab dip-net sample, macroinvertebrate species richness ranged from 9 to 23 taxa, while abundance ranged from 38 to 209 individuals per station. Physical habitat index scores ranged from 75 to 104 (maximum of 200) indicating marginal physical habitat. We report that this watershed has high concentrations of nutrients and suspended solids during the winter and spring wet season and that the macroinvertebrate communities are influenced by stream conditions, including marginal physical habitat
Ferromagnetism of He Films in the Low Field Limit
We provide evidence for a finite temperature ferromagnetic transition in
2-dimensions as in thin films of He on graphite, a model system
for the study of two-dimensional magnetism. We perform pulsed and CW NMR
experiments at fields of 0.03 - 0.48 mT on He at areal densities of 20.5 -
24.2 atoms/nm. At these densities, the second layer of He has a
strongly ferromagnetic tendency. With decreasing temperature, we find a rapid
onset of magnetization that becomes independent of the applied field at
temperatures in the vicinity of 1 mK. Both the dipolar field and the NMR
linewidth grow rapidly as well, which is consistent with a large (order unity)
polarization of the He spins.Comment: 4 figure
Association between low health literacy and adverse health behaviors in North Carolina, 2016
Introduction: Health literacy (HL) is an urgent public health challenge facing the U.S. HL is a critical factor in health inequities and exacerbates underlying social determinants of health.
Purpose: This study assesses the association between low HL (LHL) and adverse health behaviors, which contribute to poor health.
Methods: Researchers used North Carolina’s 2016 Behavioral Risk Factor Surveillance System data, namely, the Health Literacy optional module which asks respondents to rate how difficult it is for them to get health-related advice or to understand medical information (verbal or written). Health behaviors analyzed were excessive alcohol consumption, lack of adequate exercise and sleep, and irregular medical and dental check-ups. The sample was divided into four age categories (18–49, 50–64, and 65–75, and 76 and older) for statistical comparisons. Stata 15 and a user-written Stata command, -psacalc-, were used to examine the relationships by addressing omitted variable bias in OLS regressions.
Results: Findings indicate that LHL has a direct robust relationship with not exercising, inadequate sleep, irregular health and dental checkup, and health screenings across different age groups. Among women, LHL is associated with getting a Pap test in 3 years as opposed to more than 3 years.
Implications: The adverse behaviors can explain the mechanisms underlying the link between LHL and adverse health outcomes. Further research on the causal relationship between LHL and adverse health behaviors using longitudinal data on a broader geographic region is warranted
Speech-Language Pathology Graduate Student Clinicians’ Self-Perceived Competency in Dysphagia Management
Speech-language pathologists (SLPs) are the preferred healthcare providers for managing the direct clinical care of patients with dysphagia. By assessing self-perceived competency during academic training, SLP graduate student clinicians may increase their understanding of their skills in dysphagia management. We modified the Dysphagia Competency Verification Tool (DCVT) to use a 5-point ordinal scale to explore how SLP graduate student clinicians’ self-perception of competency in dysphagia management changes over time and to determine the impact of clinical practicum experiences. Seventy-two SLP graduate student clinicians rated their self-perceived competency for four DCVT domains. We used Generalized Estimating Equations (GEE) models to analyze the statistical significance of self-perception of competency ratings for each of the DCVT domains across semesters while accounting for clinical practicum experiences. Overall, the SLP graduate student clinicians indicated an increase in DCVT scores from the beginning of their graduate training program to the time of graduation, but did not perceive themselves as Adequate on most items of the DCVT until their last semester. These results suggest that both SLP graduate student clinicians and SLP graduate training programs would benefit from using a standardized metric to assess self-perceived competence in dysphagia management. DCVT self-perceived competency ratings could inform SLP graduate student clinicians about areas of dysphagia management practice and skills that need further development, allowing them to target these specific areas and gain actual competence
Physical Activity among Veterans and Nonveterans with Diabetes
Engaging in regular physical activity (PA), with or without a corresponding decrease in weight, is associated with improved health outcomes. The purpose of this study was to quantify the extent to which PA differed between veterans and nonveterans and to determine how diabetes and age influenced this association. Data from the 2009 Behavioral Risk Factor Surveillance System were used in this study. Respondents were classified as having diabetes if they reported ever being diagnosed with diabetes except during pregnancy. Respondents who reported ever serving on active military duty were classified as veterans. Based on self-report, we calculated the average minutes per week of moderate, vigorous, and total activity. After adjusting for sex, race and ethnicity, household income, education level, body mass index (BMI), and recent health checkup, veteran status was associated with a small but significantly larger amount of average weekly moderate PA (2.2 minutes, P = 0.0058) but not average weekly vigorous PA (−0.02 minutes, P = 0.98). Diabetes and prediabetes were associated with significantly lower mean levels of both moderate and vigorous intensity PA, as was increasing age. Consistent with prior research, veterans engaged in more PA than nonveterans. The association between diabetes, age, and physical activity did not differ by veteran status
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