114 research outputs found
Changing Patterns of Income Inequality in U.S. Counties, 1970–2000
The upswing in economic inequality that has affected a number of advanced industrial societies in the late 20th century has been particularly conspicuous in the United States. The authors explore its causes using data on the distribution of family income in 3,098 U.S. counties in 1970, 1980, 1990, and 2000. The authors build a model of within-county income inequality that assumes that distribution processes involving labor market and sociodemographic variables operate primarily at the county level and those involving the political and institutional context operate primarily at the state level. Multilevel methods are used to distinguish county cross-sectional, state cross-sectional, and longitudinal effects on inequality. The authors find that, when features of the state-level institutional and political context are associated with inequality, these effects are larger longitudinally than cross-sectionally. A range of other factors, including economic development, labor force changes, shifts in the racial/ethnic and gender composition of the labor force, educational expansion, and urbanization are found to have comparatively large effects, both longitudinally and cross-sectionally
How (and Why) NCLB Failed to Close the Achievement Gap:Evidence from North Carolina, 1998-2004
Recent state and national policy changes for public education are premised upon the idea that high-stakes tests can improve student outcomes and close achievement gaps. Opponents maintain that such policies fail on both counts. Using a unique longitudinal dataset from North Carolina, we find that high-stakes tests have failed to close achievement gaps associated with social class and race, and that the persistence of these gaps is related, at least in part, to academic tracking. Such findings add to the questions being raised about such policies as No Child Left Behind
Sulfation degree of glycosaminoglycans triggers distinct cytoskeleton organisation in mesenchymal stem cells
Glycosaminoglycans (GAGs) comprise the closest cellular environment: they are building
elements of the ECM and can be also found on cells surface. Their biological activity depends
on several parameters among which the negative charge is of prime importance[1]. This
charge is generally associated with the presence of sulfate groups (-OSO3H). Sulfation is
a dynamic modification: it can occur at various positions within the glycan and different
sulfation patterns have been identified for the same organs and cells during their
development. However, the mechanisms of coding and transferring information by
these functionalities are not yet complete understood, mainly because of (i)the complex
physiological microenvironment in which GAGs interactions occur and (ii)the inability to access
homogeneous GAGs[2].
In this work, we propose model surfaces bearing GAGs with different sulfation degree as
platform to investigate the pathways by which mesenchymal stem cells (MSCs) sense and
respond to this peculiar functionality: the -OSO3H. We have selected two natural GAGs for this
study: hyaluronic acid (HA) because it is the only non-sulfated glycan and heparin (HEP) as it is
the GAG with the highest degree of sulfation. To obtain a larger range of sulfation degrees, we
have also prepared a synthetic analogue of HA with a sulfation degree of 1.4 (sHA). All these
GAGs were covalently bonded to aminothiols deposited on gold surfaces. MSCs, both from
bone marrow and adipose tissue, adhered well to all surfaces. Formation of focal adhesions
was observed after only 1h of culture for bone marrow derived MSCs regardless the used
substrate. The presence of –OSO3H groups induced different morphology and cytoskeleton
organisation: formation of longer filopodia and well pronounced actin fibers were visible for
the MSCs from both sources. Moreover, cells were more spread after 24h in contact with –
OSO3H containing surfaces. Cells behaved similarly on both sulfated surfaces (sHA and HEP)
and differences in cell morphology were less obvious: higher sulfation degree induced less
lamellipodia formation while filopodia number and length increased.
In summary, the present study provides evidence that sulfation degree of GAGs triggers
distinct cytoskeleton organisation in mesenchymal stem cells that may be related with the
differentiation of those cells. However, further studies at the molecular level about the exact
mechanism of these processes need to be carried out
Centro Educativo Modelo para la Inclusión de las Personas Invidentes y Débiles Visuales en Ciudad De Dios
Ciudad de Dios, la Periferia de la ciudad de Arequipa sigue expandiéndose mas no se está desarrollando o dando una calidad de vida adecuada para las personas y más aun teniendo un Ãndice alto de personas Invidentes y Débiles Visuales, las que se sienten marginadas por la misma sociedad.
Este proyecto del Centro Educativo Modelo para la Inclusión de las Personas Invidentes y Débiles Visuales busca mejorara su calidad de vida en una sociedad donde ve su discapacidad como una limitación cuando son personas que desarrollan los demás sentidos haciendo que perciban el mundo desde otra perspectiva, con ayuda de una educación e inclusión podrán formar parte de la sociedad
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Undergraduates’ awareness of White and male privilege in STEM
Background: It is well-documented that experiences in STEM courses for women and students of color are different from the experiences of White men. As part of a larger interview study, 183 college seniors from diverse gender and race backgrounds were asked their thoughts on whether the experience of being a STEM major was different for people of different races and genders. We use a framework of “science as White property”, derived from critical race theory, to frame this study and results.
Results: White men were largely unaware of any impact of race or gender. In contrast, women of color overwhelmingly report, consistent with results from a large body of prior research, that both race and gender impact their experiences as STEM majors. Students who acknowledged race and gender impacts did not always attribute these impacts to cultural or systemic factors (i.e., some reported women are underrepresented because they are less interested in STEM rather than a structural reason). Impacts identified that were attributable to systemic factors included impacts related to being a demographic minority (i.e., intimidation, feeling out of place, feeling pressure to work harder) and/or discrimination (i.e., job discrimination, bias against women or people of color and cultural assumptions implying the superiority of White people and men). A small number of students (mostly White women) stated that women or people of color benefit from their underrepresented status, often attributing this benefit to a perception of extra encouragement and opportunities. A common theme across categorizations was that women and students of color work harder than men and White people either because they are perceived to be harder workers or as a response to the sexism and racism they encounter.
Conclusions: We found that White men are largely unaware of the impacts of race or gender on the pursuit of a STEM degree. Additionally, with the exception of women of color, students are less likely to perceive race as having an impact on the experiences of students than gender. We conclude with a discussion of implications for future work related to gender and race representation in STEM.</p
Make Better Choices (MBC): Study design of a randomized controlled trial testing optimal technology-supported change in multiple diet and physical activity risk behaviors
<p>Abstract</p> <p>Background</p> <p>Suboptimal diet and physical inactivity are prevalent, co-occurring chronic disease risk factors, yet little is known about how to maximize multiple risk behavior change. Make Better Choices, a randomized controlled trial, tests competing hypotheses about the optimal way to promote healthy change in four bundled risk behaviors: high saturated fat intake, low fruit and vegetable intake, low physical activity, and high sedentary leisure screen time. The study aim is to determine which combination of two behavior change goals - one dietary, one activity - yields greatest overall healthy lifestyle change.</p> <p>Methods/Design</p> <p>Adults (n = 200) with poor quality diet and sedentary lifestyle will be recruited and screened for study eligibility. Participants will be trained to record their diet and activities onto a personal data assistant, and use it to complete two weeks of baseline. Those who continue to show all four risk behaviors after baseline recording will be randomized to one of four behavior change prescriptions: 1) increase fruits and vegetables and increase physical activity, 2) decrease saturated fat and increase physical activity, 3) increase fruits and vegetable and decrease saturated fat, or 4) decrease saturated fat and decrease sedentary activity. They will use decision support feedback on the personal digital assistant and receive counseling from a coach to alter their diet and activity during a 3-week prescription period when payment is contingent upon meeting behavior change goals. They will continue recording on an intermittent schedule during a 4.5-month maintenance period when payment is not contingent upon goal attainment. The primary outcome is overall healthy lifestyle change, aggregated across all four risk behaviors.</p> <p>Discussion</p> <p>The Make Better Choices trial tests a disseminable lifestyle intervention supported by handheld technology. Findings will fill a gap in knowledge about optimal goal prescription to facilitate simultaneous diet and activity change. Results will shed light on which goal prescription maximizes healthful lifestyle change.</p> <p>Trial Registration</p> <p>Clinical Trials Gov. Identifier NCT00113672</p
Lost in spatial translation - A novel tool to objectively assess spatial disorientation in Alzheimer's disease and frontotemporal dementia
Spatial disorientation is a prominent feature of early Alzheimer's disease (AD) attributed to degeneration of medial temporal and parietal brain regions, including the retrosplenial cortex (RSC). By contrast, frontotemporal dementia (FTD) syndromes show generally intact spatial orientation at presentation. However, currently no clinical tasks are routinely administered to objectively assess spatial orientation in these neurodegenerative conditions. In this study we investigated spatial orientation in 58 dementia patients and 23 healthy controls using a novel virtual supermarket task as well as voxel-based morphometry (VBM). We compared performance on this task with visual and verbal memory function, which has traditionally been used to discriminate between AD and FTD. Participants viewed a series of videos from a first person perspective travelling through a virtual supermarket and were required to maintain orientation to a starting location. Analyses revealed significantly impaired spatial orientation in AD, compared to FTD patient groups. Spatial orientation performance was found to discriminate AD and FTD patient groups to a very high degree at presentation. More importantly, integrity of the RSC was identified as a key neural correlate of orientation performance. These findings confirm the notion that i) it is feasible to assess spatial orientation objectively via our novel Supermarket task; ii) impaired orientation is a prominent feature that can be applied clinically to discriminate between AD and FTD and iii) the RSC emerges as a critical biomarker to assess spatial orientation deficits in these neurodegenerative conditions
De Novo Mutations in Synaptic Transmission Genes Including DNM1 Cause Epileptic Encephalopathies
Correction to The American Journal of Human Genetics, Volume 95, Issue 4, 2 October 2014, Pages 360-370. Volume 100, Issue 1, 5 January 2017, Page 179.Peer reviewe
Response to Therapeutic Sleep Deprivation: A Naturalistic Study of Clinical and Genetic Factors and Post-treatment Depressive Symptom Trajectory
Research has shown that therapeutic sleep deprivation (SD) has rapid antidepressant effects in the majority of depressed patients. Investigation of factors preceding and accompanying these effects may facilitate the identification of the underlying biological
mechanisms. This exploratory study aimed to examine clinical and genetic factors predicting response to SD and determine the impact of SD on illness course. Mood during SD was also assessed via visual analogue scale. Depressed inpatients (n = 78) and healthy controls (n = 15) underwent ~36 h of SD. Response to SD was defined as a score of ≤ 2 on the Clinical Global Impression
Scale for Global Improvement. Depressive symptom trajectories were evaluated for up to a month using self/expert ratings. Impact of genetic burden was calculated using polygenic risk scores for major depressive disorder. In total, 72% of patients responded to SD. Responders and non-responders did not differ in baseline self/expert depression symptom ratings, but mood differed. Response was associated with lower age (p = 0.007) and later age at life-time disease onset (p = 0.003). Higher genetic burden of depression
was observed in non-responders than healthy controls. Up to a month post SD, depressive symptoms decreased in both patients groups, but more in responders, in whom effects were sustained. The present findings suggest that re-examining SD with a greater focus on biological mechanisms will lead to better understanding of mechanisms of depression
The Science Performance of JWST as Characterized in Commissioning
This paper characterizes the actual science performance of the James Webb
Space Telescope (JWST), as determined from the six month commissioning period.
We summarize the performance of the spacecraft, telescope, science instruments,
and ground system, with an emphasis on differences from pre-launch
expectations. Commissioning has made clear that JWST is fully capable of
achieving the discoveries for which it was built. Moreover, almost across the
board, the science performance of JWST is better than expected; in most cases,
JWST will go deeper faster than expected. The telescope and instrument suite
have demonstrated the sensitivity, stability, image quality, and spectral range
that are necessary to transform our understanding of the cosmos through
observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures;
https://iopscience.iop.org/article/10.1088/1538-3873/acb29
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