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To describe the genomic analysis and epidemiologic response related to a slow and prolonged methicillin-resistant Staphylococcus aureus (MRSA) outbreak.
Prospective observational study.
Neonatal intensive care unit (NICU).
We conducted an epidemiologic investigation of a NICU MRSA outbreak involving serial baby and staff screening to identify opportunities for decolonization. Whole-genome sequencing was performed on MRSA isolates.
A NICU with excellent hand hygiene compliance and longstanding minimal healthcare-associated infections experienced an MRSA outbreak involving 15 babies and 6 healthcare personnel (HCP). In total, 12 cases occurred slowly over a 1-year period (mean, 30.7 days apart) followed by 3 additional cases 7 months later. Multiple progressive infection prevention interventions were implemented, including contact precautions and cohorting of MRSA-positive babies, hand hygiene observers, enhanced environmental cleaning, screening of babies and staff, and decolonization of carriers. Only decolonization of HCP found to be persistent carriers of MRSA was successful in stopping transmission and ending the outbreak. Genomic analyses identified bidirectional transmission between babies and HCP during the outbreak.
In comparison to fast outbreaks, outbreaks that are “slow and sustained” may be more common to units with strong existing infection prevention practices such that a series of breaches have to align to result in a case. We identified a slow outbreak that persisted among staff and babies and was only stopped by identifying and decolonizing persistent MRSA carriage among staff. A repeated decolonization regimen was successful in allowing previously persistent carriers to safely continue work duties.
Typical enteropathogenic Escherichia coli (tEPEC) infection is a major cause of diarrhoea and contributor to mortality in children <5 years old in developing countries. Data were analysed from the Global Enteric Multicenter Study examining children <5 years old seeking care for moderate-to-severe diarrhoea (MSD) in Kenya. Stool specimens were tested for enteric pathogens, including by multiplex polymerase chain reaction for gene targets of tEPEC. Demographic, clinical and anthropometric data were collected at enrolment and ~60-days later; multivariable logistic regressions were constructed. Of 1778 MSD cases enrolled from 2008 to 2012, 135 (7.6%) children tested positive for tEPEC. In a case-to-case comparison among MSD cases, tEPEC was independently associated with presentation at enrolment with a loss of skin turgor (adjusted odds ratio (aOR) 2.08, 95% confidence interval (CI) 1.37–3.17), and convulsions (aOR 2.83, 95% CI 1.12–7.14). At follow-up, infants with tEPEC compared to those without were associated with being underweight (OR 2.2, 95% CI 1.3–3.6) and wasted (OR 2.5, 95% CI 1.3–4.6). Among MSD cases, tEPEC was associated with mortality (aOR 2.85, 95% CI 1.47–5.55). This study suggests that tEPEC contributes to morbidity and mortality in children. Interventions aimed at defining and reducing the burden of tEPEC and its sequelae should be urgently investigated, prioritised and implemented.
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.
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.
Dense populations of glyphosate-resistant (GR) Italian ryegrass are problematic for spring burndown herbicide programs and crop establishment in the midsouthern United States. Two field studies were conducted to evaluate fall-applied residual herbicides for control of GR Italian ryegrass and to identify the most effective application timing for these herbicides. Fall applications of clomazone at 0.84 and 1.12 kg ai ha−1, pyroxasulfone at 0.16 kg ai ha−1, and S-metolachlor at 1.79 kg ai ha−1 controlled GR Italian ryegrass ≥ 93% 180 d after application. Control from incorporated applications of pendimethalin at 1.59 kg ai ha−1 and trifluralin at 1.68 kg ai ha−1 and surface applications of S-metolachlor at 1.42 kg ha−1 provided control similar to the best treatments. Glyphosate-resistant Italian ryegrass control following clomazone, pyroxasulfone, S-metolachlor, or trifluralin applied in mid September, October, or November exceeded that from fall tillage by 19 to 56% at 90 and 140 d after the last treatment. Pyroxasulfone and S-metolachlor controlled more GR Italian ryegrass following October or November applications compared with those in September at both 90 and 140 d after the last application timing. However, the benefit of delaying clomazone application from October to November was not realized until the last evaluation (140 d after the last treatment). Clomazone, pyroxasulfone, and S-metolachlor offer growers the best opportunity for residual control of GR Italian ryegrass, and control is optimized when these herbicides are applied in November.
Introduction, Mandeep K. Dhami, Anne Schlottmann, and Michael R. Waldmann
In conclusion, rather than present a summary of the preceding chapters, we invited nine eminent past presidents of the Society for Judgment and Decision Making (SJDM) to provide personal perspectives on the concept of JDM as a dynamic skill. These scholars were not asked to comment on the chapters in this book, but rather to highlight their personal points of contact with the notion of JDM as a dynamic skill. The following perspectives offer historical accounts, and also point to future lines of research.
Shanteau describes how over the years he has highlighted the importance of training and skill acquisition in JDM, but feels “blue” that this view has not been more popular. Wallsten remembers the benefits of learning for JDM performance found in a study that he conducted 30 years ago, and confesses that he has only recently begun to revisit this important finding. Fischhoff points out that a sound understanding of the normative implications of tasks has laid a better foundation for the study of dynamically changing skills, especially in development. Levin and colleagues provide useful examples of their research on the developmental and neurological bases of JDM skills. Reyna highlights how her fuzzy trace theory taps into JDM processes that develop over time and experience, has neurological correlates, and may be evolutionarily adaptive. Baron reveals how he now finds himself in search of the developmental origins of the types of moral heuristics and biases that he has studied during his career. Hogarth shares three steps he has developed during decades of teaching decision making that can help people make better decisions. Klayman reveals that despite decades of studying learning and development of JDM, he still seeks a greater understanding of how decision makers “get that way.” Finally, Birnbaum points to the methodological factors that have limited our understanding of JDM as a skill, and presents a challenge for future researchers: to explain how and why JDM skills change. Overall, the following perspectives provide a rare glimpse of the personalized views of those who have made significant contributions to the field of human JDM.
Plate tectonics is the kinematic theory that describes the large-scale motions and events of the outermost shell of the solid Earth in terms of the relative motions and interactions of large, rigid, interlocking fragments of lithosphere called tectonic plates. Plates form and disappear incrementally over time as a result of tectonic processes. There are currently about a dozen major plates on the surface of the Earth, and many minor ones. The present-day configuration of tectonic plates is illustrated inFigure 7.1. As the interlocking plates move relative to each other, they interact at plate boundaries, where adjacent plates collide, diverge, or slide past each other. The interactions of plates result in a variety of observable surface phenomena, including the occurrence of earthquakes and the formation of large-scale surface features such as mountains, sedimentary basins, volcanoes, island arcs, and deep ocean trenches. In turn, the appearance of these phenomena and surface features indicates the location of plate boundaries. For a detailed review of the theory of plate tectonics, consult Wessel and Müller (2007).
A plate-tectonic reconstruction is the calculation of positions and orientations of tectonic plates at an instant in the history of the Earth. The visualization of reconstructions is a valuable tool for understanding the evolution of the systems and processes of the Earth's surface and near subsurface. Geological and geophysical features may be “embedded” in the simulated plates, to be reconstructed along with the plates, enabling a researcher to trace the motions of these features through time.
With the recent advances made in monochromation of electron sources and Cs-correction, the point resolution of the transmission electron microscope (TEM) has been extended into the sub-Angstrom regime. This development has led to an important consequence—that specimen preparation has become a more critical issue for the materials scientist. Nanoscale artifacts that could be tolerated a few years ago when imaging in the 0.1–0.15 nm range can no longer be allowed. An example is hydrocarbon contamination, which although only a few monolayers thick, obscures the area of interest. Other examples include residual deformation and oxidation following traditional mechanical methods. Ion-based methods may induce amorphization and implantation defects, depending on the type of ion, its energy, and the particular protocol that is used.