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We conducted a quality improvement project at a large public tertiary-care academic hospital to reduce reported hospital-acquired Clostridium difficile infection (CDI) rates. We introduced diagnostic stewardship and provider education, resulting in a 2-fold reduction in C. difficile nucleic acid amplification test (NAAT) orders and markedly lower hospital CDI rate.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
OBJECTIVES/SPECIFIC AIMS: Clinical guidelines recommend using predicted atherosclerotic cardiovascular disease (ASCVD) risk to inform treatment decisions. The objective was to compare the contribution of changes in modifiable risk factors Versus aging to the development of high 10-year predicted ASCVD risk. METHODS/STUDY POPULATION: Prospective follow-up of the Jackson Heart Study, an exclusively African-American cohort, at visit 1 (2000–2004) and visit 3 (2009–2012). Analyses included 1115 African-American participants without a high 10-year predicted ASCVD risk (<7.5%), hypertension, diabetes, or ASCVD at visit 1. We used the Pooled Cohort equations to calculate the incidence of high (≥7.5%) 10-year predicted ASCVD risk at visit 3. We recalculated the percentage with a high 10-year predicted ASCVD risk at visit 3 assuming each risk factor [age, systolic blood pressure (SBP), antihypertensive medication use, diabetes, smoking, total and high-density lipoprotein cholesterol], one at a time, did not change from visit 1. RESULTS/ANTICIPATED RESULTS: The mean age at visit 1 was 45.2±9.5 years. Overall, 30.9% (95% CI 28.3%–33.4%) of participants developed high 10-year predicted ASCVD risk. Aging accounted for 59.7% (95% CI 54.2%–65.1%) of the development of high 10-year predicted ASCVD risk compared with 32.8% (95% CI 27.0%–38.2%) for increases in SBP or antihypertensive medication initiation and 12.8% (95% CI 9.6%–16.5%) for incident diabetes. Among participants <50 years, the contribution of increases in SBP or antihypertensive medication initiation was similar to aging. DISCUSSION/SIGNIFICANCE OF IMPACT: Increases in SBP and antihypertensive medication initiation are major contributors to the development of high 10-year predicted ASCVD risk in African Americans, particularly among younger adults.
The collective response of electrons in an ultrathin foil target irradiated by an ultraintense (
) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture’, inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
“Black male exceptionalism” is the premise that African American men fare more poorly than any other group in the United States. The discourse of Black male exceptionalism presents African American men as an “endangered species.” Some government agencies, foundations, and activists have responded by creating “Black male achievement” programs. There are almost no corresponding “Black female achievement” programs. Yet empirical data does not support the claim that Black males are burdened more than Black females. Without attention to intersectionality, Black male achievement programs risk obscuring Black females and advancing patriarchal values. Black male achievement programs also risk reinforcing stereotypes that African American males are violent and dangerous. An intersectional approach would create space for Black male focused interventions, but require parity for Black female programs.
Despite providing significant benefits for human health, energy systems also negatively affect global health in major ways today, causing directly perhaps as many as five million premature deaths annually and more than 5% of all illhealth (measured as lost healthy life years). Air pollution from incomplete combustion of fossil fuels and biomass fuels is by far the single major reason that energy systems negatively affect global health, although ash, sulfur, mercury, and other contaminants in fossil fuels also play a role. Effects on workers in energy industries are the second biggest health impact globally.
The largest exposures to energy-related air pollution occur in and around households, particularly in developing countries where unprocessed biomass (wood and agricultural wastes) and coal are used for cooking and heating in simple appliances.
This chapter does not focus on differences in impacts among alternative energy systems that have minor impacts on global health; rather, the focus is on the most significant impacts of energy systems on health. The important positive impacts of energy systems on health are mostly addressed in Chapter 2.
Given the importance of avoiding climate change, there is secondary focus on the ways that mitigating climate change through changes in energy systems might achieve important health improvements: co-benefits.
Unless major policy interventions are introduced, energy systems are expected to continue contributing significantly to the global burden of disease for years to come.
Computed tomography (CT) and magnetic resonance imaging (MRI) are the mainstays of cerebral imaging. Skull radiography now plays very little part in diagnosis, being largely replaced by multislice CT.
Non- or minimally invasive angiography performed using CT (CT angiography) or MRI (magnetic resonance angiography) has resulted in invasive catheter angiography being reserved for a few special diagnostic indications or as part of an interventional, (therapeutic), procedure.
Anatomical detail is far better displayed by MRI than by CT, although both are valuable in clinical practice.
With T1-weighted (T1W) MR images, grey matter is of lower signal intensity (darker) than white matter (Fig. 1.1 ). On T2-weighted (T2W) images, including T2-FLAIR sequences, the reverse is true (Fig. 1.2).
With CT, somewhat paradoxically, white matter is depicted as darker grey than grey matter (Fig. 1.3 ). The explanation is that CT is an X-ray investigation. White matter contains lipid as part of myelin, which is relatively radiolucent.
The appearance of myelinated tracts on MRI is rather more variable and will be inl uenced by the pulse sequence
used. In perhaps its simplest form, the lipid in subcutaneous fat is typically high signal (white) on both T1 and T2 MR sequences.