429 research outputs found
Health Disparities in Colorectal Cancer Screening in United States: Race/ethnicity or Shifting Paradigms?
Background: Colorectal cancer (CRC) remains the third leading cause of cancer death in the United States. The incidence, mortality, and screening vary by race/ethnicity, with African Americans and Hispanics being disproportionately represented. Early detection through screening prolongs survival and decreases mortality. CRC screening (CRCS) varies by race/ethnicity, with lower prevalence rates observed among minorities, but the factors associated with such disparities remain to be fully understood. The current study aimed to examine the ethnic/racial disparities in the prevalence of CRCS, and the explanatory factors therein in a large sample of U.S. residents, using the National Health Interview Survey, 2003.
Materials and Methods: A cross-sectional, epidemiologic design was used with a chi squareto assess the prevalence of CRCS, while a survey logistic regression model was used to assess the odds of being screened.
Results: There was a significant variability in CRCS, with minorities demonstrating lower prevalence relative to Caucasians Ï2 (3) = 264.4, p\u3c 0.0001. After controlling for the covariates, racial/ethnic disparities in CRCS persisted. Compared to Caucasians, African Americans/Blacks were 28% (adjusted prevalence odds ratio [APOR] = 0.72, 99% CI, 0.60-0.80), while Hispanics 33% (APOR, 0.67, 99% CI, 0.53-0.84) and Asians 37% (APOR, 0.63, 99% CI, 0.43-0.95) were less likely to be screened for CRC.
Conclusion: Among older Americans, racial/ethnic disparities in CRCS exist, which was unexplained by racial/ethnic variance in the covariates associated with CRCS. These findings recommend further studies in enhancing the understanding of confounders and mediators of disparities in CRCS and the application of these factors including the health belief model in improving CRCS among ethnic/racial minorities
In search of a home : an historical analysis of the major factors concerning the location of Virginia Commonwealth University
This dissertation was written to examine the hypothesis that, although there were numerous factors affecting the selection of a site, it was primarily a financial decision to maintain the urban environment of the former Richmond Professional Institute campus as the basis of the new Academic Campus of Virginia Commonwealth University. Other factors involved in the decision include political, historical, social and academic ones.;The political factor involved a division between the City of Richmond and the County of Henrico as to the location of the Academic Campus of Virginia Commonwealth University. Senator William F. Parkerson, Jr., of Henrico County fought hard to win the political plum of a new university in his district located on the Elko Tract. The City of Richmond succeeded in its attempts to have the Academic Campus of Virginia Commonwealth University remain on the existing site of the Richmond Professional Institute.;Historically, the Richmond Professional Institute had always been closely bound to the City of Richmond, was named after the city, had drawn heavily upon the resources of the city for its adjunct faculty and related resources, and its student population was generally associated with the City of Richmond. The Elko Tract had no such historical ties to demand a change from urban to rural.;Social benefits associated with the Richmond Professional Institute site include the ready accessibility to business centers for student employment. No indication is given that a change in location would have preserved these social benefits which were possible by maintaining the status quo.;The major academic factor was that of an urban university which would use the city as an academic laboratory. From its inception as a school of social work, the Richmond Professional Institute had been closely tied to the urban setting.;The need to combine two distinct institutions into one new university was another significant academic factor. The proximity of the two campuses was important for students and faculty to cross campus lines and take or teach classes on both campuses.;Financial factors were the ultimate determinants of site selection. The value of the existing physical plant, regardless of condition, of the Richmond Professional Institute could not be ignored. The cost of creating a new and expensive campus was far outweighed by the benefit to be derived from using the existing one as a base for beginning a new university
Jasmonate and auxin perception : how plants keep F-boxes in check
Phytohormones regulate the plasticity of plant growth and development, and responses to biotic and abiotic stresses. Many hormone signal transduction cascades involve ubiquitination and subsequent degradation of proteins by the 26S proteasome. The conjugation of ubiquitin to a substrate is facilitated by the E1 activating, E2 conjugating, and the substrate-specifying E3 ligating enzymes. The most prevalent type of E3 ligase in plants is the Cullin-RING ligase (CRL)-type, with F-box proteins (FBPs) as the substrate recognition component. The activity of these SKP-Cullin-F-box (SCF) complexes needs to be tightly regulated in time and place. Here, we review the regulation of SCF function in plants on multiple levels, with a focus on the auxin and jasmonate SCF-type receptor complexes. We discuss in particular the relevance of protein-protein interactions and post-translational modifications as mechanisms to keep SCF functioning under control. Additionally, we highlight the unique property of SCFTIR1/AFB and SCFCOI1 to recognize substrates by forming co-receptor complexes. Finally, we explore how engineered selective agonists can be used to study and uncouple the outcomes of the complex auxin and jasmonate signaling networks that are governed by these FBPs
A dual sgRNA approach for functional genomics in Arabidopsis thaliana
Reverse genetics uses loss-of-function alleles to interrogate gene function. The advent of CRISPR/Cas9-based gene editing now allows the generation of knock-out alleles for any gene and entire gene families. Even in the model plant Arabidopsis thaliana, gene editing is welcomed as T-DNA insertion lines do not always generate null alleles. Here, we show efficient generation of heritable mutations in Arabidopsis using CRISPR/Cas9 with a workload similar to generating overexpression lines. We obtain for several different genes Cas9 null-segregants with bi-allelic mutations in the T2 generation. While somatic mutations were predominantly generated by the canonical non-homologous end joining (cNHEJ) pathway, we observed inherited mutations that were the result of synthesis-dependent microhomology-mediated end joining (SD-MMEJ), a repair pathway linked to polymerase theta (PolQ). We also demonstrate that our workflow is compatible with a dual sgRNA approach in which a gene is targeted by two sgRNAs simultaneously. This paired nuclease method results in more reliable loss-of-function alleles that lack a large essential part of the gene. The ease of the CRISPR/Cas9 workflow should help in the eventual generation of true null alleles of every gene in the Arabidopsis genome, which will advance both basic and applied plant research
Formation of hot tear under controlled solidification conditions
Aluminum alloy 7050 is known for its superior mechanical properties, and thus finds its application in aerospace industry. Vertical direct-chill (DC) casting process is typically employed for producing such an alloy. Despite its advantages, AA7050 is considered as a "hard-to-cast" alloy because of its propensity to cold cracking. This type of cracks occurs catastrophically and is difficult to predict. Previous research suggested that such a crack could be initiated by undeveloped hot tears (microscopic hot tear) formed during the DC casting process if they reach a certain critical size. However, validation of such a hypothesis has not been done yet. Therefore, a method to produce a hot tear with a controlled size is needed as part of the verification studies. In the current study, we demonstrate a method that has a potential to control the size of the created hot tear in a small-scale solidification process. We found that by changing two variables, cooling rate and displacement compensation rate, the size of the hot tear during solidification can be modified in a controlled way. An X-ray microtomography characterization technique is utilized to quantify the created hot tear. We suggest that feeding and strain rate during DC casting are more important compared with the exerted force on the sample for the formation of a hot tear. In addition, we show that there are four different domains of hot-tear development in the explored experimental window-compression, microscopic hot tear, macroscopic hot tear, and failure. The samples produced in the current study will be used for subsequent experiments that simulate cold-cracking conditions to confirm the earlier proposed model.This research was carried out within the Materials innovation institute (www.m2i.nl) research framework, project no. M42.5.09340
Surface and Boundary Layer Exchanges of Volatile Organic Compounds, Nitrogen Oxides and Ozone During the GABRIEL Campaign
Abstract. We present an evaluation of sources, sinks and turbulent transport of nitrogen oxides, ozone and volatile organic compounds (VOC) in the boundary layer over French Guyana and Suriname during the October 2005 GABRIEL campaign by simulating observations with a single-column chemistry and climate model (SCM) along a zonal transect. Simulated concentrations of O3 and NO as well as NO2 photolysis rates over the forest agree well with observations when a small soil-biogenic NO emission flux was applied. This suggests that the photochemical conditions observed during GABRIEL reflect a pristine tropical low-NOx regime. The SCM uses a compensation point approach to simulate nocturnal deposition and daytime emissions of acetone and methanol and produces daytime boundary layer mixing ratios in reasonable agreement with observations. The area average isoprene emission flux, inferred from the observed isoprene mixing ratios and boundary layer height, is about half the flux simulated with commonly applied emission algorithms. The SCM nevertheless simulates too high isoprene mixing ratios, whereas hydroxyl concentrations are strongly underestimated compared to observations, which can at least partly explain the discrepancy. Furthermore, the model substantially overestimates the isoprene oxidation products methlyl vinyl ketone (MVK) and methacrolein (MACR) partly due to a simulated nocturnal increase due to isoprene oxidation. This increase is most prominent in the residual layer whereas in the nocturnal inversion layer we simulate a decrease in MVK and MACR mixing ratios, assuming efficient removal of MVK and MACR. Entrainment of residual layer air masses, which are enhanced in MVK and MACR and other isoprene oxidation products, into the growing boundary layer poses an additional sink for OH which is thus not available for isoprene oxidation. Based on these findings, we suggest pursuing measurements of the tropical residual layer chemistry with a focus on the nocturnal depletion of isoprene and its oxidation products.JRC.H.2-Climate chang
Care Transitions From Patient and Caregiver Perspectives
PURPOSE: Despite concerted actions to streamline care transitions, the journey from hospital to home remains hazardous for patients and caregivers. Remarkably little is known about the patient and caregiver experience during care transitions, the services they need, or the outcomes they value. The aims of this study were to (1) describe patient and caregiver experiences during care transitions and (2) characterize patient and caregiver desired outcomes of care transitions and the health services associated with them.
METHODS: We interviewed 138 patients and 110 family caregivers recruited from 6 health networks across the United States. We conducted 34 homogenous focus groups (103 patients, 65 caregivers) and 80 key informant interviews (35 patients, 45 caregivers). Audio recordings were transcribed and analyzed using principles of grounded theory to identify themes and the relationship between them.
RESULTS: Patients and caregivers identified 3 desired outcomes of care transition services: (1) to feel cared for and cared about by medical providers, (2) to have unambiguous accountability from the health care system, and (3) to feel prepared and capable of implementing care plans. Five care transition services or provider behaviors were linked to achieving these outcomes: (1) using empathic language and gestures, (2) anticipating the patient\u27s needs to support self-care at home, (3) collaborative discharge planning, (4) providing actionable information, and (5) providing uninterrupted care with minimal handoffs.
CONCLUSIONS: Clear accountability, care continuity, and caring attitudes across the care continuum are important outcomes for patients and caregivers. When these outcomes are achieved, care is perceived as excellent and trustworthy. Otherwise, the care transition is experienced as transactional and unsafe, and leaves patients and caregivers feeling abandoned by the health care system
Black-White Risk Differentials in COVID-19 (SARS-COV2) Transmission, Mortality and Case Fatality in the United States: Translational Epidemiologic Perspective and Challenges
Background: Social and health inequities predispose vulnerable populations to adverse morbidity and mortality outcomes of epidemics and pandemics. While racial disparities in cumulative incidence (CmI) and mortality from the influenza pandemics of 1918 and 2009 implicated Blacks with survival disadvantage relative to Whites in the United States, COVID-19 currently indicates comparable disparities. We aimed to: (a) assess COVID-19 CmI by race, (b) determine the Black-White case fatality (CF) and risk differentials, and (c) apply explanatory model for mortality risk differentials. Methods: COVID-19 data on confirmed cases and deaths by selective states health departments were assessed using a cross-sectional ecologic design. Chi-square was used for CF independence, while binomial regression model for the Black-White risk differentials. Results: The COVID-19 mortality CmI indicated Blacks/AA with 34% of the total mortality in the United States, albeit their 13% population size. The COVID-19 CF was higher among Blacks/AA relative to Whites; Maryland, (2.7% vs. 2.5%), Wisconsin (7.4% vs. 4.8%), Illinois (4.8% vs. 4.2%), Chicago (5.9% vs. 3.2%), Detroit (Michigan), 7.2% and St. John the Baptist Parish (Louisiana), 7.9%. Blacks/AA compared to Whites in Michigan were 15% more likely to die, CmI risk ratio (CmIRR) = 1.15, 95% CI, 1.01-1.32. Blacks/AA relative to Whites in Illinois were 13% more likely to die, CmIRR = 1.13, 95% CI, 0.93-1.39, while Blacks/AA compared to Whites in Wisconsin were 51% more likely to die, CmIRR = 1.51, 95% CI, 1.10-2.10. In Chicago, Blacks/AA were more than twice as likely to die, CmIRR = 2.24, 95% CI, 1.36-3.88. Conclusion: Substantial racial/ethnic disparities are observed in COVID-19 CF and mortality with Blacks/AA disproportionately affected across the United States
Can a âstate of the artâ chemistry transport model simulate Amazonian tropospheric chemistry?
We present an evaluation of a nested high-resolution Goddard Earth Observing System (GEOS)-Chem chemistry transport model simulation of tropospheric chemistry over tropical South America. The model has been constrained with two isoprene emission inventories: (1) the canopy-scale Model of Emissions of Gases and Aerosols from Nature (MEGAN) and (2) a leaf-scale algorithm coupled to the Lund-Potsdam-Jena General Ecosystem Simulator (LPJ-GUESS) dynamic vegetation model, and the model has been run using two different chemical mechanisms that contain alternative treatments of isoprene photo-oxidation. Large differences of up to 100 Tg C yr^(â1) exist between the isoprene emissions predicted by each inventory, with MEGAN emissions generally higher. Based on our simulations we estimate that tropical South America (30â85°W, 14°Nâ25°S) contributes about 15â35% of total global isoprene emissions. We have quantified the model sensitivity to changes in isoprene emissions, chemistry, boundary layer mixing, and soil NO_x emissions using ground-based and airborne observations. We find GEOS-Chem has difficulty reproducing several observed chemical species; typically hydroxyl concentrations are underestimated, whilst mixing ratios of isoprene and its oxidation products are overestimated. The magnitude of model formaldehyde (HCHO) columns are most sensitive to the choice of chemical mechanism and isoprene emission inventory. We find GEOS-Chem exhibits a significant positive bias (10â100%) when compared with HCHO columns from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI) for the study year 2006. Simulations that use the more detailed chemical mechanism and/or lowest isoprene emissions provide the best agreement to the satellite data, since they result in lower-HCHO columns
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