1,385 research outputs found
Magnetically levitated mesenchymal stem cell spheroids cultured with a collagen gel maintain phenotype and quiescence
Multicellular spheroids are an established system for three-dimensional cell culture. Spheroids are typically generated
using hanging drop or non-adherent culture; however, an emerging technique is to use magnetic levitation. Herein,
mesenchymal stem cell spheroids were generated using magnetic nanoparticles and subsequently cultured within a type
I collagen gel, with a view towards developing a bone marrow niche environment. Cells were loaded with magnetic
nanoparticles, and suspended beneath an external magnet, inducing self-assembly of multicellular spheroids. Cells in
spheroids were viable and compared to corresponding monolayer controls, maintained stem cell phenotype and were
quiescent. Interestingly, core spheroid necrosis was not observed, even with increasing spheroid size, in contrast to
other commonly used spheroid systems. This mesenchymal stem cell spheroid culture presents a potential platform for
modelling in vitro bone marrow stem cell niches, elucidating interactions between cells, as well as a useful model for
drug delivery studies
Manager's Role in Electromagnetic Interference (EMI) Control
This presentation captures the essence of electromagnetic compatibility (EMC) engineering from a project manager's perspective. It explains the basics of EMC and the benefits to the project of early incorporation of EMC best practices. The EMC requirement products during a project life cycle are identified, along with the requirement verification methods that should be utilized. The goal of the presentation is to raise awareness and simplify the mystique surrounding electromagnetic compatibility for managers that have little or no electromagnetics backgroun
Space Power Facility Reverberation Chamber Calibration Report
This document describes the process and results of calibrating the Space Environmental Test EMI Test facility at NASA Plum Brook Space Power Facility according to the specifications of IEC61000-4-21 for susceptibility testing from 100 MHz to 40 GHz. The chamber passed the field uniformity test, in both the empty and loaded conditions, making it the world's largest Reverberation Chamber
NASA Applications for Computational Electromagnetic Analysis
Computational Electromagnetic Software is used by NASA to analyze the compatibility of systems too large or too complex for testing. Recent advances in software packages and computer capabilities have made it possible to determine the effects of a transmitter inside a launch vehicle fairing, better analyze the environment threats, and perform on-orbit replacements with assured electromagnetic compatibility
Anxious/depressed symptoms are related to microstructural maturation of white matter in typically developing youths
AbstractThere are multiple recent reports of an association between anxious/depressed (A/D) symptomatology and the rate of cerebral cortical thickness maturation in typically developing youths. We investigated the degree to which anxious/depressed symptoms are tied to age-related microstructural changes in cerebral fiber pathways. The participants were part of the NIH MRI Study of Normal Brain Development. Child Behavior Checklist A/D scores and diffusion imaging were available for 175 youths (84 males, 91 females; 241 magnetic resonance imagings) at up to three visits. The participants ranged from 5.7 to 18.4 years of age at the time of the scan. Alignment of fractional anisotropy data was implemented using FSL/Tract-Based Spatial Statistics, and linear mixed model regression was carried out using SPSS. Child Behavior Checklist A/D was associated with the rate of microstructural development in several white matter pathways, including the bilateral anterior thalamic radiation, bilateral inferior longitudinal fasciculus, left superior longitudinal fasciculus, and right cingulum. Across these pathways, greater age-related fractional anisotropy increases were observed at lower levels of A/D. The results suggest that subclinical A/D symptoms are associated with the rate of microstructural development within several white matter pathways that have been implicated in affect regulation, as well as mood and anxiety psychopathology.</jats:p
Accumulation of metabolic cardiovascular risk factors in black and white young adults over 20 years
BACKGROUND: Cross-sectional clustering of metabolic risk factors for cardiovascular disease in middle-aged adults is well described, but less is known regarding the order in which risk factors develop through young adulthood and their relation to subclinical atherosclerosis.
METHOD AND RESULTS: A total of 3178 black and white women and men in the Coronary Artery Risk Development in Young Adults study were assessed to identify the order in which cardiovascular disease risk factors including diabetes, hypertension, dyslipidemia (low high-density lipoprotein cholesterol or high triglyceride levels), hypercholesterolemia (high total or low-density lipoprotein cholesterol), and obesity develop. Observed patterns of risk factor development were compared with those expected if risk factors accumulated randomly, given their overall distribution in the population. Over the 20 years of follow-up, 80% of participants developed at least 1 risk factor. The first factor to occur was dyslipidemia in 39% of participants, obesity in 20%, hypercholesterolemia in 11%, hypertension in 7%, and diabetes in 1%. Dyslipidemia was the only risk factor both to occur first and to be followed by additional risk factors more often than expected (P \u3c 0.001 for both). Order of risk factor accrual did not affect subclinical atherosclerosis at year 20. Results were similar by sex, race, and smoking status.
CONCLUSIONS: Multiple patterns of cardiovascular risk factor development were observed from young adulthood to middle age. Dyslipidemia, a potentially modifiable condition, often preceded the development of other risk factors and may be a useful target for intervention and monitoring
A Colorimetric Chemosensor Based on a Nozoe Azulene That Detects Fluoride in Aqueous/Alcoholic Media
Colorimetry is an advantageous method for detecting fluoride in drinking water in a resource-limited context, e. g., in parts of the developing world where excess fluoride intake leads to harmful health effects. Here we report a selective colorimetric chemosensor for fluoride that employs an azulene as the reporter motif and a pinacolborane as the receptor motif. The chemosensor, NAz-6-Bpin, is prepared using the Nozoe azulene synthesis, which allows for its rapid and low-cost synthesis. The chemosensor gives a visually observable response to fluoride both in pure organic solvent and also in water/alcohol binary solvent mixtures
Vegetable diversity, injurious falls, and fracture risk in older women: A prospective cohort study
The importance of vegetable diversity for the risk of falling and fractures is unclear. Our objective was to examine the relationship between vegetable diversity with injurious falling and fractures leading to hospitalization in a prospective cohort of older Australian women (n = 1429, â„70 years). Vegetable diversity was quantified by assessing the number of different vegetables consumed daily. Vegetable intake (75 g servings/day) was estimated using a validated food frequency questionnaire at baseline (1998). Over 14.5 years, injurious falls (events = 568, 39.7%), and fractures (events = 404, 28.3%) were captured using linked health records. In multivariable-adjusted Cox regression models, women with greater vegetable diversity (per increase in one different vegetable/day) had lower relative hazards for falls (8%; p = 0.02) and fractures (9%; p = 0.03). A significant interaction between daily vegetable diversity (number/day) and total vegetable intake (75 g servings/day) was observed for falls (pinteraction = 0.03) and fractures (pinteraction \u3c 0.001). The largest benefit of higher vegetable diversity were observed in the one third of women with the lowest vegetable intake (\u3c2.2 servings/day; falls HR 0.83 95% CI (0.71â0.98); fractures HR 0.74 95% CI (0.62â0.89)). Increasing vegetable diversity especially in older women with low vegetable intake may be an effective way to reduce injurious fall and fracture risk
Dietary nitrate intake is associated with muscle function in older women
Background
In younger individuals, dietary nitrate supplementation has been shown to improve shortâterm vascular and muscle function. The role of higher habitual nitrate intake as part of a typical diet on muscle function in ageing has not been investigated. A crossâsectional study of relationships between dietary nitrate and measures of muscle function in older communityâdwelling Australian women (n = 1420, â„70 years) was undertaken. Methods
Participants completed a semiâquantitative food frequency questionnaire assessing dietary intake over the previous year. Total nitrate from vegetables and nonâvegetable sources was calculated from a validated instrument that quantified the nitrate content of food recorded within the food frequency questionnaire. Handgrip strength and timedâupâandâgo (TUG) were assessed, representing muscle strength and physical function, respectively. Cutâpoints for weak grip strength (kg) and slow TUG (\u3e10.2 s) were selected due to their association with adverse outcomes. Linear and logistic regressions were used to examine the relationship between total nitrate intake and muscle function measures. Results
Mean ± standard deviation (SD) total nitrate intake was 79.5 ± 31.2 mg/day, of which 84.5% came from vegetables. Across the unadjusted tertiles of nitrate intake (P= 0.027) and faster TUG (per second, ÎČ â0.27, P = 0.001). The proportion of women with weak grip strength (kg) or slow TUG (\u3e10.2 s) was 61.0% and 36.9%, respectively. Each SD higher nitrate intake (31.2 mg/day) was associated with lower odds for weak grip strength (OR 0.84, 95% CI 0.74â0.95, P = 0.005) and slow TUG (OR 0.86, 95% CI 0.76â0.98, P = 0.021). Compared with women in the lowest tertile of nitrate intake, women in the highest nitrate intake tertile had lower odds for weak grip strength (OR 0.65, 95% CI 0.49â0.87, Ptrend=0.004) and slow TUG (OR 0.72, 95% CI 0.53â0.97, Ptrend = 0.044). Conclusions
This investigation highlights potential benefits of nitrateârich diets on muscle strength and physical function in a large cohort of older women. Considering poor muscle strength and physical function is associated with a range of adverse health outcomes such as falling, fractures, cardiovascular disease, and mortality, increasing dietary nitrate, especially though vegetable consumption may be an effective way to limit ageârelated declines in muscle function
Program Notes: The Newsletter of Literary Managers and Dramaturgs of America, volume 2, number 3
Convention Issue: Report from the President, They Showed Us in Missouri: A Personal View, Membership News,Regional News and Views: Celtic Writers, New Plays Down South, Bay Area New Play Development, LMDA Responds to McNally, Profiles in Dramaturgy: Richard Pettengill, American Developmental Theater, On the Western Front, New Play Venues in New York City, and Poses and Postures in the Southeast.
Issue editors: Richard E. Kramer, Jeffery Lawson, and Laurence Maslonhttps://soundideas.pugetsound.edu/lmdareview/1004/thumbnail.jp
- âŠ