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We propose here a method to experimentally quantify unsteady leading-edge flow separation on aerofoils with finite thickness. The methodology relies on the computation of a leading-edge suction parameter based on measured values of the partial circulation around the leading edge and the stagnation point location. We validate the computation of the leading-edge suction parameter for both numerical and experimental data under steady and unsteady flow conditions. The leading-order approximation of the definition of the leading-edge suction parameter is proven to be sufficiently accurate for the application to thin aerofoils such as the NACA0009 without a priori knowledge of the stagnation point location. The higher-order terms including the stagnation point location are required to reliably compute the leading-edge suction parameter on thicker aerofoils such as the NACA0015. The computation of the leading-edge suction parameter from inviscid flow theory does not assume the Kutta condition to be valid at the trailing edge which allows us to compute its value for separated flows. The relation between the leading-edge suction parameter and the evolution of the shear layer height is studied in two different unsteady flow conditions, a fixed aerofoil in a fluctuating free-stream velocity and a pitching aerofoil in a steady free stream. We demonstrate here that the instantaneous value of the leading-edge suction parameter based on the partial circulation around the leading edge is unambiguously defined for a given flow field and can serve as a directly quantitative measure of the degree of unsteady flow separation at the leading edge.
Evidence-based diagnostic methods have clinical and research applications in neuropsychology. A flexible Bayesian model was developed to yield diagnostic posttest probabilities from a single person’s neuropsychological score profile by utilizing sample descriptive statistics of the test battery across diagnostic populations of interest.
Three studies examined the model’s performance. One simulation examined estimation accuracy of true z-scores. A diagnostic accuracy simulation utilized descriptive statistics from two popular neuropsychological tests, the Wechsler Adult Intelligence Scale–IV (WAIS-IV) and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The final simulation examined posterior predictive accuracy of scores to those reported in the WAIS manual.
The model produced minimally biased z-score estimates (root mean square errors: .02–.18) with appropriate credible intervals (95% credible interval empirical coverage rates: .94–1.00). The model correctly classified 80.87% of simulated normal, mild cognitive impairment, and Alzheimer’s disease cases using a four subtest WAIS-IV and the RBANS compared to accuracies of 60.67–65.60% from alternative methods. The posterior predictions of raw scores closely aligned to percentile estimates published in the WAIS-IV manual.
This model permits estimation of posttest probabilities for various combinations of neuropsychological tests across any number of clinical populations with the principal limitation being the accessibility of applicable reference samples. The model produced minimally biased estimates of true z-scores, high diagnostic classification rates, and accurate predictions of multiple reported percentiles while using only simple descriptive statistics from reference samples. Future nonsimulation research on clinical data is needed to fully explore the utility of such diagnostic prediction models.
An accurate estimate of the average number of hand hygiene opportunities per patient hour (HHO rate) is required to implement group electronic hand hygiene monitoring systems (GEHHMSs). We sought to identify predictors of HHOs to validate and implement a GEHHMS across a network of critical care units.
Multicenter, observational study (10 hospitals) followed by quality improvement intervention involving 24 critical care units across 12 hospitals in Ontario, Canada.
Critical care patient beds were randomized to receive 1 hour of continuous direct observation to determine the HHO rate. A Poisson regression model determined unit-level predictors of HHOs. Estimates of average HHO rates across different types of critical care units were derived and used to implement and evaluate use of GEHHMS.
During 2,812 hours of observation, we identified 25,417 HHOs. There was significant variability in HHO rate across critical care units. Time of day, day of the week, unit acuity, patient acuity, patient population and use of transmission-based precautions were significantly associated with HHO rate. Using unit-specific estimates of average HHO rate, aggregate HH adherence was 30.0% (1,084,329 of 3,614,908) at baseline with GEHHMS and improved to 38.5% (740,660 of 1,921,656) within 2 months of continuous feedback to units (P < .0001).
Unit-specific estimates based on known predictors of HHO rate enabled broad implementation of GEHHMS. Further longitudinal quality improvement efforts using this system are required to assess the impact of GEHHMS on both HH adherence and clinical outcomes within critically ill patient populations.
The Repugnant Conclusion is an implication of some approaches to population ethics. It states, in Derek Parfit's original formulation,
For any possible population of at least ten billion people, all with a very high quality of life, there must be some much larger imaginable population whose existence, if other things are equal, would be better, even though its members have lives that are barely worth living. (Parfit 1984: 388)
Background: The current approach to measuring hand hygiene (HH) relies on human auditors who capture <1% of HH opportunities and rapidly become recognized by staff, resulting in inflation in performance. Our goal was to assess the impact of group electronic monitoring coupled with unit-led quality improvement on HH performance and prevention of healthcare-associated transmission and infection. Methods: A stepped-wedge cluster randomized quality improvement study was undertaken across 5 acute-care hospitals in Ontario, Canada. Overall, 746 inpatient beds were electronically monitored across 26 inpatient medical and surgical units. Daily HH performance as measured by group electronic monitoring was reported to inpatient units who discussed results to guide unit-led improvement strategies. The primary outcome was monthly HH adherence (%) between baseline and intervention. Secondary outcomes included transmission of antibiotic resistant organisms such as methicillin resistant Staphylococcus aureus (MRSA) and other healthcare-associated infections. Results: After adjusting for the correlation within inpatient units, there was a significant overall improvement in HH adherence associated with the intervention (IRR, 1.73; 95% CI, 1.47–1.99; P < .0001). Monthly HH adherence relative to the intervention increased from 29% (1,395,450 of 4,544,144) to 37% (598,035 of 1,536,643) within 1 month, followed by consecutive incremental increases up to 53% (804,108 of 1,515,537) by 10 months (P < .0001). We identified a trend toward reduced healthcare-associated transmission of MRSA (0.74; 95% CI, 0.53–1.04; P = .08). Conclusions: The introduction of a system for group electronic monitoring led to rapid, significant, and sustained improvements in HH performance within a 2-year period.
Five marsupial species are recognized from the Brule Formation at two localities in southwestern North Dakota: Fitterer Ranch and Obritsch Ranch (middle Oligocene; Whitneyan North American Land Mammal Age [NALMA]). The herpetotheriids Herpetotherium fugax Cope, 1873a, Copedelphys superstes new species, and the peradectid Nanodelphys hunti (Cope, 1873b) are represented at both localities. A fourth species is H. sp., cf. H. merriami (Stock and Furlong, 1922), represented by a single specimen from Fitterer Ranch, being limited elsewhere to the later Arikareean NALMA. A fifth species is represented by two isolated lower cheek teeth, interpreted as m1s, from Fitterer Ranch that are unique in lacking a trigonid (only two cusps present) while having a well-developed talonid. These specimens are referred to an indeterminate herpetotheriine species. The new species of Copedelphys is distinct from other species of the genus in that the anterior two lower molars are enlarged relative to the posterior molars. Overall, this new species is more similar in proportions to the latest Eocene (Chadronian) C. titanelix (Matthew, 1903) than the Oligocene (Orellan and Whitneyan) C. stevensoni (Cope, 1873b). This study adds a third and fourth Whitneyan marsupial fauna from the Great Plains region of North America, increases the known diversity of Whitneyan marsupials, and provides further evidence that marsupial diversity during the late Paleogene in North America was relatively stable until the late early Arikareean NALMA.
Global Cumulative Treatment Analysis (GCTA) is a novel clinical research model combining expert knowledge, and treatment coordination based upon global information-gain, to treat every patient optimally while efficiently searching the vast space that is the realm of cancer research.
We use deep Chandra and HST data to uniquely classify the X-ray binary (XRB) populations in M81 on the basis of their donor stars and local stellar populations (into early-type main sequence, yellow giant, supergiant, low-mass, and globular cluster). First, we find that more massive, redder, and denser globular clusters are more likely to be associated with XRBs. Second, we find that the high-mass XRBs (HMXBs) overall have a steeper X-ray luminosity function (XLF) than the canonical star-forming galaxy XLF, though there is some evidence of variations in the slopes of the sub-populations. On the other hand, the XLF of the prototypical starburst M82 is described by the canonical powerlaw (αcum ∼ 0.6) down to LX ∼ 1036 erg s−1. We attribute variations in XLF slopes to different mass transfer modes (Roche-lobe overflow versus wind-fed systems).
We analyse the vertical distribution of High Mass X-ray Binaries (HMXBs) in NGC 55, the nearest edge-on galaxy to the Milky Way. Our analysis reveals significant spatial offsets of HMXBs from the star forming regions, greater than those observed in the SMC and the LMC but similar with the Milky Way. The spatial offsets can be explained by a momentum kick the X-ray binaries receive during the formation of the compact object. The difference between the scale height of the vertical distribution of HMXBs and the vertical distribution of star-forming activity is 0.48±0.04 kpc. The centre-of-mass velocity of the distribution of HMXBs in NGC 55 is moving at a velocity of 52.4±11.4 km s−1, greater than the corresponding velocity of HMXBs in the SMC and LMC, but consistent with velocities of Milky Way HMXBs.
Terror management theory (TMT) posits that cultural worldviews function to allay concerns about human mortality. Preliminary research with older adults has indicated that seniors do not respond to death reminders in the same way as their younger counterparts. The purpose of the current study was to test a developmentally relevant construct that may buffer death anxiety in later life. It was hypothesized that Erikson’s concept of generativity may encompass death-denying properties for older adults. One hundred and seventy-nine seniors were recruited to determine if subtle mortality salience inductions would lead participants to rate their own generativity as higher than after a blatant induction, or no induction, after controlling for pre-induction generativity. As expected, participants exposed to subtle death primes rated themselves as having higher levels of generativity than the other two groups after co-varying pre-induction generativity. Explanations are discussed in light of the literatures on TMT and generativity.
Cover crop–based organic rotational no-till soybean production has attracted attention from farmers, researchers, and other agricultural professionals because of the ability of this new system to enhance soil conservation, reduce labor requirements, and decrease diesel fuel use compared to traditional organic production. This system is based on the use of cereal rye cover crops that are mechanically terminated with a roller-crimper to create in situ mulch that suppresses weeds and promotes soybean growth. In this paper, we report experiments that were conducted over the past decade in the eastern region of the United States on cover crop–based organic rotational no-till soybean production, and we outline current management strategies and future research needs. Our research has focused on maximizing cereal rye spring ground cover and biomass because of the crucial role this cover crop plays in weed suppression. Soil fertility and cereal rye sowing and termination timing affect biomass production, and these factors can be manipulated to achieve levels greater than 8,000 kg ha−1, a threshold identified for consistent suppression of annual weeds. Manipulating cereal rye seeding rate and seeding method also influences ground cover and weed suppression. In general, weed suppression is species-specific, with early emerging summer annual weeds (e.g., common ragweed), high weed seed bank densities (e.g. > 10,000 seeds m−2), and perennial weeds (e.g., yellow nutsedge) posing the greatest challenges. Due to the challenges with maximizing cereal rye weed suppression potential, we have also found high-residue cultivation to significantly improve weed control. In addition to cover crop and weed management, we have made progress with planting equipment and planting density for establishing soybean into a thick cover crop residue. Our current and future research will focus on integrated multitactic weed management, cultivar selection, insect pest suppression, and nitrogen management as part of a systems approach to advancing this new production system.
Whey protein intake reduces CVD risk, but little is known whether whey-derived bioactive peptides regulate vascular endothelial function (VEF). We determined the impact of a whey-derived extract (NOP-47) on VEF in individuals with an increased cardiovascular risk profile. Men and women with impaired brachial artery flow-mediated dilation (FMD) (n 21, age 55 (sem 1·3) years, BMI 27·8 (sem 0·6) kg/m2, FMD 3·7 (sem 0·4) %) completed a randomised, cross-over study to examine whether ingestion of NOP-47 (5 g) improves postprandial VEF. Brachial artery FMD, plasma amino acids, insulin, and endothelium-derived vasodilators and vasoconstrictors were measured for 2 h after ingestion of NOP-47 or placebo. Acute NOP-47 ingestion increased FMD at 30 min (4·6 (sem 0·5) %) and 120 min (5·1 (sem 0·5) %) post-ingestion (P< 0·05, time × trial interaction), and FMD responses at 120 min were significantly greater in the NOP-47 trial compared with placebo (4·3 (sem 0·5) %). Plasma amino acids increased at 30 min following NOP-47 ingestion (P< 0·05). Serum insulin increased at 15, 30 and 60 min (P< 0·001) following NOP-47 ingestion. No changes were observed between the trials for plasma NO∙ and prostacyclin metabolites or endothelin-1. Ingestion of a rapidly absorbed extract derived from whey protein improved endothelium-dependent dilation in older adults by a mechanism independent of changes in circulating vasoactive compounds. Future investigation is warranted in individuals at an increased CVD risk to further elucidate potential health benefits and the underlying mechanisms of extracts derived from whey.
Scientists overwhelmingly agree that the climate is changing and that the changes are largely due to increased levels of carbon emissions into the atmosphere that are caused by human activities. The recommended response from society to climate change involves two sets of activities: mitigation and adaptation. Adaptation includes activities that attempt to adjust or respond to changes to the environment caused by climate change. For wildlife, a consensus is forming around an approach to adaptation planning that would improve the ability of an ecosystem to resist dramatic changes to habitats; build resilience into the ecosystem to recover from extreme weather events and changes in temperature and precipitation that may cause increased floods, wildfires, insect outbreaks, etc.; and lastly build realignment into our ecosystems through wildlife corridors or other connections through matrix landscape types that allow species to shift their ranges and transition into new areas when the need becomes inevitable. This commentary outlines a climate change adaptation strategy for wildlife within an eight-state region (Minnesota, Iowa, Missouri, Wisconsin, Illinois, Michigan, Indiana, and Ohio) of the Midwest United States (US) focused on the design of an interconnected green infrastructure network of natural areas that helps refine future wildlife habitat conservation priorities while also providing other natural and human benefits to residents of the Midwest US. A landscape-scale green infrastructure network will be developed for this area within the next 18–24 months thanks to a grant from the US Fish and Wildlife Service to the eight Midwest states, and the strategy outlined here serves as the foundation for implementing effective wildlife habitat protection projects in response to climate change.