3,322 research outputs found
Comprehensive analysis of the chromatin landscape in Drosophila melanogaster.
Chromatin is composed of DNA and a variety of modified histones and non-histone proteins, which have an impact on cell differentiation, gene regulation and other key cellular processes. Here we present a genome-wide chromatin landscape for Drosophila melanogaster based on eighteen histone modifications, summarized by nine prevalent combinatorial patterns. Integrative analysis with other data (non-histone chromatin proteins, DNase I hypersensitivity, GRO-Seq reads produced by engaged polymerase, short/long RNA products) reveals discrete characteristics of chromosomes, genes, regulatory elements and other functional domains. We find that active genes display distinct chromatin signatures that are correlated with disparate gene lengths, exon patterns, regulatory functions and genomic contexts. We also demonstrate a diversity of signatures among Polycomb targets that include a subset with paused polymerase. This systematic profiling and integrative analysis of chromatin signatures provides insights into how genomic elements are regulated, and will serve as a resource for future experimental investigations of genome structure and function
Critical Spaces for Critical Times: Global Conversations in Literacy Research as an Open Professional Development and Practices Resource
This paper reflects an OER (Open Educational Resources) critical literacy project, Global Conversations in Literacy Research (GCLR), (www.globalconversationsinliteracy.wordpress.com), now in its fourth year. GCLR annually hosts seven web seminars presented by internationally recognized literacy and education scholars. We outline key dimensions of GCLR not only as an OER but as an open educational practice (OEP) (Andrade et al., 2011) that through its design, not only provides open access to scholarship, but also understands the critical nexus among resources, practices and theory. Informed by data from a longitudinal study, this paper situates these dimensions within professional development literature, and outlines GCLR as a critical space designed for critical times, and the importance of intentionality when accessing OER. Like scholars before us, we argue that that availability is not the only consideration when using OER (Andrade et al., 2011); OER must be considered in relation to pedagogical considerations and how OER are used as a critical component to online professional development
ACE-ASIA - Regional climatic and atmospheric chemical effects of Asian dust and pollution
Although continental-scale plumes of Asian dust and pollution reduce the amount of solar radiation reaching the earth's surface and perturb the chemistry of the atmosphere, our ability to quantify these effects has been limited by a lack of critical observations, particularly of layers above the surface. Comprehensive surface, airborne, shipboard, and satellite measurements of Asian aerosol chemical composition, size, optical properties, and radiative impacts were performed during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) study. Measurements within a massive Chinese dust storm at numerous widely spaced sampling locations revealed the highly complex structure of the atmosphere, in which layers of dust, urban pollution, and biomass-burning smoke may be transported long distances as distinct entities or mixed together. The data allow a first-time assessment of the regional climatic and atmospheric chemical effects of a continental-scale mixture of dust and pollution. Our results show that radiative flux reductions during such episodes are sufficient to cause regional climate change
Percent body fat estimations in college women using field and laboratory methods: a three-compartment model approach
This is the publisher's version, also available electronically from http://www.jissn.com/content/4/1/16.Background
Methods used to estimate percent body fat can be classified as a laboratory or field technique. However, the validity of these methods compared to multiple-compartment models has not been fully established. This investigation sought to determine the validity of field and laboratory methods for estimating percent fat (%fat) in healthy college-age women compared to the Siri three-compartment model (3C).
Methods
Thirty Caucasian women (21.1 ± 1.5 yrs; 164.8 ± 4.7 cm; 61.2 ± 6.8 kg) had their %fat estimated by BIA using the BodyGram™ computer program (BIA-AK) and population-specific equation (BIA-Lohman), NIR (Futrex® 6100/XL), a quadratic (SF3JPW) and linear (SF3WB) skinfold equation, air-displacement plethysmography (BP), and hydrostatic weighing (HW).
Results
All methods produced acceptable total error (TE) values compared to the 3C model. Both laboratory methods produced similar TE values (HW, TE = 2.4%fat; BP, TE = 2.3%fat) when compared to the 3C model, though a significant constant error (CE) was detected for HW (1.5%fat, p ≤ 0.006). The field methods produced acceptable TE values ranging from 1.8 – 3.8 %fat. BIA-AK (TE = 1.8%fat) yielded the lowest TE among the field methods, while BIA-Lohman (TE = 2.1%fat) and NIR (TE = 2.7%fat) produced lower TE values than both skinfold equations (TE > 2.7%fat) compared to the 3C model. Additionally, the SF3JPW %fat estimation equation resulted in a significant CE (2.6%fat, p ≤ 0.007).
Conclusion
Data suggest that the BP and HW are valid laboratory methods when compared to the 3C model to estimate %fat in college-age Caucasian women. When the use of a laboratory method is not feasible, NIR, BIA-AK, BIA-Lohman, SF3JPW, and SF3WB are acceptable field methods to estimate %fat in this population
Statistics of Two-point Correlation and Network Topology for Lyman Alpha Emitters at
We investigate the spatial distribution of Lyman alpha emitting galaxies
(LAEs) at , selected from the NOAO Deep Wide-Field Survey
(NDWFS), using two-point statistics and topological diagnostics adopted from
network science. We measure the clustering length, Mpc,
and the bias, . Fitting the clustering with halo
occupation distribution (HOD) models results in two disparate possibilities:
(1) where the fraction of central galaxies is 1% in halos of mass
; and (2) where the fraction is 20%. We refer to
these two scenarios as the `Dusty Core Scenario' for Model#1 since most of
central galaxies in massive halos are dead in Ly emission, and the
`Pristine Core Scenario' for Model#2 since the central galaxies are bright in
Ly emission. Traditional two-point statistics cannot distinguish
between these disparate models given the current data sets. To overcome this
degeneracy, we generate mock catalogs for each HOD model using a high
resolution -body simulation and adopt a network statistics approach, which
provides excellent topological diagnostics for galaxy point distributions. We
find three topological anomalies from the spatial distribution of observed
LAEs, which are not reproduced by the HOD mocks. We find that Model#2 matches
better all network statistics than Model#1, suggesting that the central
galaxies in halos at need to be
less dusty to be bright as LAEs, potentially implying some replenishing
channels of pristine gas such as the cold mode accretion.Comment: 23 pages, 18 figures, accepted by MNRA
Kommunikationsempfehlungen zur Verbesserung des Verhaltens bei der Verwendung von PoC Antigen-Schnelltests und Selbsttests
Die breitere Anwendung von Antigentests zum Auffinden einer akuten Infektion mit SARS-CoV-2 beinhaltet Chancen, aber auch Risiken und Limitationen. Die Tests können als einer von mehreren Bausteinen zur Pandemiekontrolle beitragen, indem sie die Erkennung von Infektionen und somit die Unterbrechung von Infektionsketten ermöglichen - insbesondere durch wiederholte, engmaschige Testungen derselben Personen. Der Beitrag fasst die wichtigsten Aspekte zusammen und gibt evidenzbasierte Tipps zur Kommunikation rund um die PoC Antigen-Schnelltests und Selbsttests
Macronutrient Intake, Diagnosis Status, and Glycemic Control Among US Hispanics/Latinos With Diabetes
CONTEXT: Diet modification is a mainstay of diabetes management. US Hispanics/Latinos are disproportionately affected by diabetes, but few studies have examined dietary intake among US Hispanics/Latinos with diabetes, and little is known regarding the influence of diabetes awareness on dietary intake.
OBJECTIVE: We evaluated macronutrient intake and its associations with diabetes awareness and glycemic control among US Hispanics/Latinos with diabetes.
PARTICIPANTS: This analysis included 3310 diabetic adults aged 18–74 years from the Hispanic Community Health Study/Study of Latinos (2008–2011).
MAIN OUTCOME MEASURES: Diabetes was defined as diagnosed (based on medical history or antihyperglycemic medication use) or undiagnosed diabetes (based on fasting glucose ≥ 126 mg/dL, glycated hemoglobin [HbA1c] ≥ 6.5%, or 2 h glucose ≥ 200 mg/dL in the absence of a physician diagnosis). Dietary intake was assessed using two 24-hour recalls.
RESULTS: Among Hispanic/Latino adults with diabetes, 21.2%, 55.7%, and 71.2% met the American Diabetes Association recommendations for fiber (≥14 g per 1000 kcal), saturated fat (<10% of total energy), and cholesterol intake (<300 mg), respectively. Compared with those with undiagnosed diabetes, people with diagnosed diabetes consumed less carbohydrate (50.3 vs 52.4% of total energy; P = .017), total sugar (19.1 vs 21.5% of total energy; P = .002), added sugar (9.8 vs 12.1% of total energy; P < .001), and more total fat (30.7 vs 29.3% of total energy; P = .048) and monounsaturated fat (11.5 vs 10.7% of total energy; P = .021). Association between diabetes awareness and low total and added sugar intake was observed in individuals of Mexican and Puerto Rican background but not in other groups (P for interaction < .05). Among people with diagnosed diabetes, those with HbA1c of 7% or greater consumed more total fat, saturated fat, and cholesterol than those with HbA1c less than 7% (all P < .05).
CONCLUSIONS: Among US Hispanics/Latinos with diabetes, fiber intake is low, and diabetes awareness is associated with reduced carbohydrate and sugar intake and increased monounsaturated fat intake. Sugar intake may require special attention in certain Hispanic/Latino background groups
Seismic evidence for thermal runaway during intermediate-depth earthquake rupture
Intermediate-depth earthquakes occur at depths where temperatures and pressures exceed those at which brittle failure is expected. There are two leading candidates for the physical mechanism behind these earthquakes: dehydration embrittlement and self-localizing thermal shear runaway. A complete energy budget for a range of earthquake sizes can help constrain whether either of these mechanisms might play a role in intermediate-depth earthquake rupture. The combination of high stress drop and low radiation efficiency that we observe for M[subscript w] 4–5 earthquakes in the Bucaramanga Nest implies a temperature increase of 600–1000°C for a centimeter-scale layer during earthquake failure. This suggests that substantial shear heating, and possibly partial melting, occurs during intermediate-depth earthquake failure. Our observations support thermal shear runaway as the mechanism for intermediate-depth earthquakes, which would help explain differences in their behavior compared to shallow earthquakes.National Science Foundation (U.S.) (Grant EAR-1045684
Percent body fat estimations in college women using field and laboratory methods: a three-compartment model approach
This is the publisher's version, also available electronically from http://www.jissn.com/content/4/1/16.Background
Methods used to estimate percent body fat can be classified as a laboratory or field technique. However, the validity of these methods compared to multiple-compartment models has not been fully established. This investigation sought to determine the validity of field and laboratory methods for estimating percent fat (%fat) in healthy college-age women compared to the Siri three-compartment model (3C).
Methods
Thirty Caucasian women (21.1 ± 1.5 yrs; 164.8 ± 4.7 cm; 61.2 ± 6.8 kg) had their %fat estimated by BIA using the BodyGram™ computer program (BIA-AK) and population-specific equation (BIA-Lohman), NIR (Futrex® 6100/XL), a quadratic (SF3JPW) and linear (SF3WB) skinfold equation, air-displacement plethysmography (BP), and hydrostatic weighing (HW).
Results
All methods produced acceptable total error (TE) values compared to the 3C model. Both laboratory methods produced similar TE values (HW, TE = 2.4%fat; BP, TE = 2.3%fat) when compared to the 3C model, though a significant constant error (CE) was detected for HW (1.5%fat, p ≤ 0.006). The field methods produced acceptable TE values ranging from 1.8 – 3.8 %fat. BIA-AK (TE = 1.8%fat) yielded the lowest TE among the field methods, while BIA-Lohman (TE = 2.1%fat) and NIR (TE = 2.7%fat) produced lower TE values than both skinfold equations (TE > 2.7%fat) compared to the 3C model. Additionally, the SF3JPW %fat estimation equation resulted in a significant CE (2.6%fat, p ≤ 0.007).
Conclusion
Data suggest that the BP and HW are valid laboratory methods when compared to the 3C model to estimate %fat in college-age Caucasian women. When the use of a laboratory method is not feasible, NIR, BIA-AK, BIA-Lohman, SF3JPW, and SF3WB are acceptable field methods to estimate %fat in this population
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