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We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Calling in staff and preparing the operating room for an urgent surgical procedure is a significant draw on hospital resources and disrupts care of other patients. It has been common practice to treat open fractures on an urgent basis. HTA methods can be applied to examine this prioritization of care, just like they can be applied to the acquisition of drugs and devices.
Our center completed a rapid systematic review of guidelines, systematic reviews, and primary clinical evidence, on urgent surgical debridement and stabilization of open fractures of long bones (“urgent” being defined as within six hours of the injury) compared to surgical debridement and reduction performed at a later time point. Meta-analyses were performed for infection and non-union outcomes and the GRADE system was used to assess the strength of evidence for each conclusion.
We found no published clinical guidelines for the urgency of treating open fractures. A good systematic review on the topic was published in 2012. We found six cohort studies published since completion of the earlier review. The summary odds ratio for any infection in patients with later treatment was 0.97 (95% confidence interval (CI) 0.78–1.22, sixteen studies, 3,615 patients) and for deep or “major” infections was 1.00 (95% CI 0.74–1.34, nine studies, 2,013 patients). The summary odds ratio of non-union with later treatment was 0.95 (95% CI 0.65–1.41, six studies, 1,308 patients). There was no significant heterogeneity in any of the results (I-squared = 0 percent) and no apparent trends in the results as a function of study size or publication date. We graded the strength of each of the conclusions as very low because they were based on cohort studies where the treating physician could elect immediate treatment for patients with severe soft-tissue injuries or patients at risk of complications. This raises the risk of spectrum bias.
Default urgent scheduling of patients with open fractures for surgical debridement and stabilization does not appear to reduce the risk of infection or fracture non-union. Based on this information, our surgery department managers no longer schedule patients with open fractures for immediate surgery unless there are specific circumstances necessitating it.
A majority of transplanted organs come from donors after brain death (BD). Renal grafts from these donors have higher delayed graft function and lower long-term survival rates compared to living donors. We designed a novel porcine BD model to better delineate the incompletely understood inflammatory response to BD, hypothesizing that adhesion molecule pathways would be upregulated in BD.
Animals were anesthetized and instrumented with monitors and a balloon catheter, then randomized to control and BD groups. BD was induced by inflating the balloon catheter and animals were maintained for 6 hours. RNA was extracted from kidneys, and gene expression pattern was determined.
In total, 902 gene pairs were differently expressed between groups. Eleven selected pathways were upregulated after BD, including cell adhesion molecules.
These results should be confirmed in human organ donors. Treatment strategies should target involved pathways and lessen the negative effects of BD on transplantable organs.
Misdiagnosis of asymptomatic bacteriuria as catheter-associated urinary tract infection (CAUTI) leads to unnecessary tests and other low-value care. We used this topic as the prototype to develop a clinical pathways program to promote evidence-based decision making in a multi-hospital system.
We convened a task force including hospital and critical care physicians, nurses, laboratory staff, and informatics specialists. Our Health Technology Asessment (HTA) center completed a rapid systematic review on guidelines and algorithms for diagnosing CAUTI. Additional rapid reviews were completed as necessary to address specific follow-up questions. A draft pathway based on the guidelines was developed, and then the task force edited it in an iterative process.
We used the Dorsata platform (Dorsata Inc., Washington, DC) to create, distribute and maintain the pathway. Dorsata has both desktop and mobile interfaces that guide clinicians through decision algorithms. Individual pathways include links to references and a portal for direct user feedback. Pathway owners have access to a real-time pathway utilization dashboard.
A standardized order set with the pathway was added to our electronic health record system. We also held educational meetings for residents and provided “huddle sheets” to nurse educators at each hospital. Posters and computer screen savers were also used to raise awareness of the new pathway.
We now have a total of 111 pathways on Dorsata, developed following the same model as the CAUTI evaluation pathway. Some topics, like breast cancer, have as many as sixteen pathways, addressing different clinical questions like first- and second-line therapy. Over 600 individuals have registered for the mobile app, including attending and resident physicians, nurses, and medical students. The pathway site had 1,619 views in December 2016, the most recent month for which complete records are available. The pathways are proving to have an effect on clinical decision making. For example, the annualized number of unnecessary urine cultures avoided as a result of the pathway is 4,474; resulting in estimated direct cost savings of USD67,110.
Using pathways to present HTA information at the point of care is feasible and can improve the value of care.
Health Technology Assessment (HTA) methods are usually applied to the evaluation of drugs, devices, and procedures. We have used HTA to promote evidence-based decision-making on topics relating to staffing and career development for healthcare professionals. Interventions to reduce the stress associated with caring for patients who need repeated hospitalization such as patients with sickle cell disease are thought to improve job satisfaction and nurse retention, but is there scientific evidence to support them?
We systematically searched Medline, CINAHL, PsycINFO, Cochrane, and Joanna Briggs Institute databases for published studies evaluating interventions targeting healthcare personnel. Searches combined tems for sickle cell disease with terms for job stress, turnover, and other career-related outcomes. We evaluated the quality of individual studies using standardized checklists and constructed evidence tables.
We found one randomized trial (RCT) of an education program for nurses and physicians, a pre-post analysis of a communication skills and cultural awareness program, and a case study of a nurse support group. The RCT found that an education program significantly improved participants attitude towards patients but did not measure any outcomes relating to caregiver stress or job satisfaction. The pre-post study found that a communication skills program significantly improved nurses confidence in their ability to communicate with patients. The case study reported that nurses found the support group useful and felt their attitudes were improved, but there was no control group to compare their responses to. The education program was graded as moderate-strength evidence and the other programs had low-strength evidence. There was no meta-analysis or other data synthesis of the results because of the differing interventions and outcome measures.
There have been few quantitative scientific evaluations of the effectiveness of interventions to reduce the stress nurses feel when caring for sickle cell disease patient. The studies that have been published have favorable conclusions towards these interventions, but the strength of evidence is not high.
Having frequent family dinners is associated with better diet quality in children; however, it is unknown whether the frequency of certain family meal types (i.e. dinner) is more strongly associated with better child weight and diet quality compared with other meal types (i.e. breakfast, lunch). Thus, the current study examined the frequency of eating breakfast, lunch or dinner family meals and associations with pre-school children’s overall diet quality (HEI-2010) and BMI percentile.
Cross-sectional baseline data (2012–2014) from two randomized controlled childhood obesity prevention trials, NET-Works and GROW, were analysed together.
Studies were carried out in community and in-home settings in urban areas of Minnesota and Tennessee, USA.
Parent–child (ages 2–5 years) pairs from Minnesota (n 222 non-Hispanics; n 312 Hispanics) and Tennessee (n 545 Hispanics; n 55 non-Hispanics) participated in the study.
Over 80 % of families ate breakfast or lunch family meals at least once per week. Over 65 % of families ate dinner family meals ≥5 times/week. Frequency of breakfast family meals and total weekly family meals were significantly associated with healthier diet quality for non-Hispanic pre-school children (P<0·05), but not for Hispanic children. Family meal frequency by meal type was not associated with BMI percentile for non-Hispanic or Hispanic pre-school children.
Breakfast family meal frequency and total weekly family meal frequency were associated with healthier diet quality in non-Hispanic pre-school children but not in Hispanic children. Longitudinal research is needed to clarify the association between family meal type and child diet quality and BMI percentile.
Since their inception, the Perspectives in Logic and Lecture Notes in Logic series have published seminal works by leading logicians. Many of the original books in the series have been unavailable for years, but they are now in print once again. In this volume, the third publication in the Lecture Notes in Logic series, Mitchell and Steel construct an inner model with a Woodin cardinal and develop its fine structure theory. This work builds upon the existing theory of a model of the form L[E], where E is a coherent sequence of extenders, and relies upon the fine structure theory of L[E] models with strong cardinals, and the theory of iteration trees and 'backgrounded' L[E] models with Woodin cardinals. This work is what results when fine structure meets iteration trees.