1,362 research outputs found
River systems and their water and sediment fluxes towards the marine regions of the Mediterranean Sea and Black Sea earth system. An overview
A quantitative assessment of the riverine freshwater, suspended and dissolved sediment loads is provided for the watersheds of the four primary (Western Mediterranean-WMED, Central Mediterranean-CMED, Eastern Mediterranean-EMED and Black Sea-BLS) and eleven secondary marine regions of the Mediterranean and Black Sea Earth System (MBES). On the basis of measured values that cover spatially >65% and >84% of MED and BLS watersheds, respectively, water discharge of the MBES reaches annually almost the 1 million km3, with Mediterranean Sea (including the Marmara Sea) to provide 576 km3 and the Black Sea (included the Azov Sea) 418 km3. Among the watersheds of MED primary marine regions, the total water load is distributed as follows: WMED= 180 km3; CMED= 209 km3; and EMED= 187 km3. The MBES could potentially provide annually some 894 106 t of suspended sediment load (SSL), prior to river damming, most of which (i.e., 708 106 t is attributed to MED). Between MED primary marine regions, CMED receives the highest amount of suspended sediment (287 106 t), followed by WMED (239 106 t) and EMED 182 106 t, while 185 106 t are delivered to BLS. The dissolved load (DL) of MBES is about 376 106 t, from which 215 106 t (approximately 57%) is provided by the MED watershed. The large river systems (watershed>104 km2) provide >85% of the water load, >80% of SSL and >60% of DL of both MED and BLS
Prior residency improves the performance of a habitat specialist in a degrading environment
The effect of habitat loss on the decline of habitat specialists has been well documented in coral reef fishes, since they have a restricted habitat preference. However, the different competitive advantages of specialists and generalists can impact their performance within varying habitat conditions. The order in which species arrive into a community influences competitive outcomes; these ‘priority effects’ may modify communities within degrading resource scenarios as individuals migrate in search of higher quality resources. In this study, we investigated: how sequence and timing of arrival affects interactions between a habitat generalist and a specialist in healthy and degrading environments, and how prior residency interacts with habitat quality and species identity to affect propensity to migrate. We conducted manipulative field studies using the damselfishes Pomacentrus amboinensis, a habitat generalist, and Pomacentrus moluccensis, a live coral specialist, on live or dead coral habitats, with timing of arrival differing between early and late arrivers (residents and intruders, respectively) by 1, 3 or 24 h. Our results demonstrated that the strength of priority effects (i.e., aggression intensity) increased with increasing timing of arrival when the P. moluccensis arrived after P. amboinensis, suggesting that as the perceived value of the habitat patch increased (owing to increasing ownership duration and defence investment), the tendency to defend it increased. Propensity to migrate from dead to live coral was greater for P. moluccensis compared to P. amboinensis; however, arriving after P. amboinensis significantly reduced willingness to migrate to its preferred live coral habitat, indicating an inhibitory priority effect, directly affecting future persistence. The degree that ecological versatility and priority effects combine to modify competitive outcomes in coral reef fishes has important consequences for the persistence of specialist species in the face of environmental degradation, and has implications for predicting how our changing environment will affect fish communities
Changing the Frame: Civic Engagement Through a Racial Equity Lens
This report challenges past narratives suggesting Chicago's civic life is precarious and offers a broader analysis of civic life using a racial equity lens. According to the analysis, race and class differences in civic engagement disappear or reverse when including a wide range of less formal activities and forms of collective organizing practiced among Black, Latinx, and working-class people in Chicago.Since the 1960s, traditional measures of civic engagement have shown declining rates of civic health. These accounts of civic decline often focus exclusively on voting and donating one's time, talent, and income to traditional nonprofit organizations. This report provides new ways to assess civic life in Chicago, including participation in social movements like the immigrant rights movement, the growth in the number of nonprofits established, and social cohesion as captured through the hosting of block parties.Through interviews and analysis of nonprofits in Chicago, the report captures the perspective of organizers, academics, and funders who provide their unique perspectives on the state of civic engagement in Chicago. By framing civic engagement through a racial equity lens, the report provides a broader view of civic participation that can be used to catalyze and drive action
Honorable John D. Clifford, Jr. A Memoir by His Three Law Clerks
The domain over which United States District Judge John D. Clifford, Jr. presided from 1947 until his death in 1956 was very different from what it is today. Anyone could walk into the federal courthouse in Portland. Security guards were unknown, and lawyers, litigants, and passers-by were free to come and go. A leisurely air pervaded all the court offices. There was no hurry. This was an era when there were only two lawyers in the United States Attorney\u27s office: the United States Attorney and his one assistant
Practitioner compression force variation in mammography : a 6 year study
The application of breast compression in mammography may be more heavily influenced by the practitioner
rather than the client. This could affect image quality and will affect client experience. This study builds on
previous research to establish if mammography practitioners vary in the compression force they apply over a six year period.
This longitudinal study assessed 3 consecutive analogue screens of 500 clients within one screening centre in
the UK. Recorded data included: practitioner code, applied pressure (daN), breast thickness (mm), BI-RADS®
density category and breast dose. Exclusion criteria included: previous breast surgery, previous/ongoing
assessment, breast implants. 344 met inclusion criteria. Data analysis: assessed variation of compression force
(daN) and breast thickness (mm) over 3 sequential screens to determine whether compression force and breast
thickness were affected by practitioner variations.
Compression force over the 3 screens varied significantly; variation was highly dependent upon the practitioner
who performed the mammogram. Significant thickness and compression force differences over the 3 screens
were noted for the same client (<0.0001). The amount of compression force applied was highly dependent upon
the practitioner. Practitioners fell into one of three practitioner compression groups by their compression force
mean values; high (mean 12.6daN), intermediate (mean 8.9daN) and low (mean 6.7daN).
For the same client, when the same practitioner performed the 3 screens, maximum compression force variations
were low and not significantly different (p>0.31). When practitioners from different compression force groups
performed 3 screens, maximum compression force variations were higher and significantly different (p<0.0001).
The amount of compression force used is highly dependent upon practitioner rather than client. This has
implications for radiation dose, patient experience and image quality consistency
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Application of an advanced atmospheric mesoscale model to dispersion in the Rocky Flats, Colorado vicinity
Atmospheric Studies in Complex Terrain (ASCOT) program sponsored a field experiment in the winter of 1991 near Rocky Flats, Colorado. Both meteorological and tracer dispersion measurements were taken. These two data sets provided an opportunity to investigate the influence of terrain-generated, radiatively-driven flows on the dispersion of the tracer. We use the Regional Atmospheric Modeling System (RAMS), originally developed at Colorado State University, to simulate meteorological conditions and tracer dispersion on the case night of 4-5 February 1991. The simulations described herein reveal considerable information about the extent to which the Rocky Mountains influence the flow along the Front Range , the importance of diffusion when simulating drainage flows and the computing needs of simulations in complex terrain regions
Functional Mutations Form at CTCF-Cohesin Binding Sites in Melanoma Due to Uneven Nucleotide Excision Repair across the Motif
© 2016 The Author(s) CTCF binding sites are frequently mutated in cancer, but how these mutations accumulate and whether they broadly perturb CTCF binding are not well understood. Here, we report that skin cancers exhibit a highly specific asymmetric mutation pattern within CTCF motifs attributable to ultraviolet irradiation and differential nucleotide excision repair (NER). CTCF binding site mutations form independently of replication timing and are enriched at sites of CTCF/cohesin complex binding, suggesting a role for cohesin in stabilizing CTCF-DNA binding and impairing NER. Performing CTCF ChIP-seq in a melanoma cell line, we show CTCF binding site mutations to be functional by demonstrating allele-specific reduction of CTCF binding to mutant alleles. While topologically associating domains with mutated CTCF anchors in melanoma contain differentially expressed cancer-associated genes, CTCF motif mutations appear generally under neutral selection. However, the frequency and potential functional impact of such mutations in melanoma highlights the need to consider their impact on cellular phenotype in individual genomes.Link_to_subscribed_fulltex
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