Highlights • Most did not seek alcohol treatment to achieve long-term abstinence. • Instead, many participants reported on alternative pathways to recovery. • These included housing, harm reduction, ...social connection, meaningful activity.
HYPOTHESIS A novel approach to identify at-risk periods among orthopedic surgical residents may direct fatigue risk mitigation and facilitate targeted interventions. DESIGN A prospective cohort study ...with a minimum 2-week continuous assessment period. Data on sleep and awake periods were processed using the sleep, activity, fatigue, and task effectiveness model. SETTING Rotations at 2 academic tertiary care centers. PARTICIPANTS Twenty-seven of 33 volunteer orthopedic surgical residents (82%) completed the study, representing 65% (33 of 51) of the orthopedic residency program. INTERVENTION Residents' sleep and awake periods were continuously recorded via actigraphy, and a daily questionnaire was used to analyze mental fatigue. MAIN OUTCOME MEASURES Percentage of time at less than 80% mental effectiveness (correlating with an increased risk of error), percentage of time at less than 70% mental effectiveness (correlating with a blood alcohol level of 0.08%), the mean amount of daily sleep, and the relative risk of medical error compared with chance. RESULTS Residents were fatigued during 48% and impaired during 27% of their time awake. Among all residents, the mean amount of daily sleep was 5.3 hours. Overall, residents' fatigue levels were predicted to increase the risk of medical error by 22% compared with well-rested historical control subjects. Night-float residents were more impaired (P = .02), with an increased risk of medical error (P = .045). CONCLUSIONS Resident fatigue is prevalent, pervasive, and variable. To guide targeted interventions, fatigue modeling can be conducted in hospitals to identify periods, rotations, and individuals at risk of medical error.
Abstract Background Prognostic indices for patients with brain metastases (BM) are needed to individualize treatment and stratify clinical trials. Two frequently used tools to estimate survival in ...patients with BM are the Recursive Partitioning Analysis (RPA) and the diagnosis-specific Graded Prognostic Assessment (DS-GPA). Given recent advances in therapies and improved survival for patients with BM, this study aims to validate and analyze these two models in a modern cohort. Methods Patients diagnosed with BM were identified via our institution’s Tumor Board meetings. Data were retrospectively collected from the date of diagnosis with BM. Concordance of the RPA and GPA was calculated using Harrell’s C index. A Cox proportional hazards model with backwards elimination was used to generate a parsimonious model predictive of survival. Results Our study consisted of 206 patients diagnosed with BM between 2010 and 2019. The RPA had a prediction performance characterized by Harrell’s C index of 0.588. The DS-GPA demonstrated a Harrell’s C index of 0.630. A Cox proportional hazards model assessing the effect of age, presence of lung or liver metastases, and ECOG performance status score of 3/4 on survival yielded a Harrell’s C index of 0.616. Revising the analysis with an uncategorized ECOG demonstrated a C index of 0.648. Conclusion We found that performance of the RPA remains unchanged from previous validation studies a decade earlier. The DS-GPA outperformed the RPA in predicting overall survival in our modern cohort. Analyzing variables shared by the RPA and DS-GPA produced a model that performed analogously to the DS-GPA.
Summertime aerosol optical extinction (βext) was measured in the Colorado Front Range and Denver metropolitan area as part of the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) ...campaign during July–August 2014. An Aerodyne cavity attenuated phase shift particle light extinction monitor (CAPS-PMex) was deployed to measure βext (at average relative humidity of 20 ± 7 %) of submicron aerosols at λ = 632 nm at 1 Hz. Data from a suite of gas-phase instrumentation were used to interpret βext behavior in various categories of air masses and sources. Extinction enhancement ratios relative to CO (Δβext ∕ ΔCO) were higher in aged urban air masses compared to fresh air masses by ∼ 50 %. The resulting increase in Δβext ∕ ΔCO for highly aged air masses was accompanied by formation of secondary organic aerosols (SOAs). In addition, the impacts of aerosol composition on βext in air masses under the influence of urban, natural oil and gas operations (O&G), and agriculture and livestock operations were evaluated. Estimated non-refractory mass extinction efficiency (MEE) values for different air mass types ranged from 1.51 to 2.27 m2 g−1, with the minimum and maximum values observed in urban and agriculture-influenced air masses, respectively. The mass distribution for organic, nitrate, and sulfate aerosols presented distinct profiles in different air mass types. During 11–12 August, regional influence of a biomass burning event was observed, increasing the background βext and estimated MEE values in the Front Range.
Simulated primary organic aerosols (POA), as well as other particulates and trace gases, in the vicinity of Mexico City are evaluated using measurements collected during the 2006 Megacity Initiative: ...Local and Global Research Observations (MILAGRO) field campaigns. Since the emission inventories, transport, and turbulent mixing will directly affect predictions of total organic matter and consequently total particulate matter, our objective is to assess the uncertainties in predicted POA before testing and evaluating the performance of secondary organic aerosol (SOA) treatments. Carbon monoxide (CO) is well simulated on most days both over the city and downwind, indicating that transport and mixing processes were usually consistent with the meteorological conditions observed during MILAGRO. Predicted and observed elemental carbon (EC) in the city was similar, but larger errors occurred at remote locations since the overall CO/EC emission ratios in the national emission inventory were lower than in the metropolitan emission inventory. Components of organic aerosols derived from Positive Matrix Factorization of data from several Aerodyne Aerosol Mass Spectrometer instruments deployed both at ground sites and on research aircraft are used to evaluate the model. Modeled POA was consistently lower than the measured organic matter at the ground sites, which is consistent with the expectation that SOA should be a large fraction of the total organic matter mass. A much better agreement was found when modeled POA was compared with the sum of "primary anthropogenic" and "biomass burning" components derived from Positive Matrix Factorization (PMF) on most days, especially at the surface sites, suggesting that the overall magnitude of primary organic particulates released was reasonable. However, simulated POA from anthropogenic sources was often lower than "primary anthropogenic" components derived from PMF, consistent with two recent reports that these emissions are underestimated. The modeled POA was greater than the total observed organic matter when the aircraft flew directly downwind of large fires, suggesting that biomass burning emission estimates from some large fires may be too high.
To compare the functional stability of Cetaphil UVA/UVB Defense SPF 50 as measured by its ultraviolet B sun protection factor (UVB-SPF) and ultraviolet A protection factor (UVA-PF) values following ...exposure to natural sunlight versus the UVB-SPF and UVA-PF values of unexposed product.
These two randomized, controlled, evaluator-blinded, single-center trials were conducted according to the methods outlined in the 2007 Proposed Amendment to the Final Monograph, “Sunscreen Drug Products for Over-the-Counter Human Use.” Sunscreen samples were applied to glass plates and exposed to ultraviolet radiation in the form of natural sunlight in four minimal erythemal doses (MED) ranging from 2–6 MED (42–36 mJ/cm2). Three test sites were identified on the back of each study subject. Exposed sunscreen (one of four doses), unexposed sunscreen, and a UVB-SPF 15 control sunscreen were applied to the three test sites in a randomized fashion, followed by UV irradiation of incremental doses. Erythema and pigment darkening responses were assessed immediately following UV exposure and again 16–24 hours (erythema) or three to 24 hours (pigment darkening) after exposure. UVB-SPF and UVA-PF values were calculated for the exposed and unexposed samples.
The calculated UVB-SPF and UVA-PF values for all test samples (exposed and unexposed) were >50 and >9, respectively, which were greater than the stated UVB-SPF and UVA-PF values on the product label. No differences were observed between the exposed and unexposed samples in UVB-SPF or UVA-PF.
The UVA and UVB protection using standard evaluation techniques of Cetaphil UVA/UVB Defense SPF 50 remains stable despite exposure of the sunscreen to natural sunlight containing UVB ranging from 2–16 MED (41–336 mJ/cm2) and coexistent UVA.
Increased small bowel epithelial cell apoptosis and decreased cell proliferation lead to impairment of gut mucosal integrity and function after thermal injury. Impairment of gut integrity is ...associated with increased bacterial translocation and incidence of sepsis. The purpose of this study was to determine whether IGF-I/IGF binding protein (IGFBP)-3 can improve small bowel homeostasis after injury and by which cellular mechanisms these changes occur and to identify changes in apoptosis-related genes after burn and the effect of bile acid on small bowel epithelial cell apoptosis after burn. Rats sustained a thermal injury and received saline or the IGF-I/IGFBP-3 complex. Serum and small intestine were taken at 1, 2, 5, and 7 d after injury and serum inflammatory cytokines and mucosal apoptosis, proliferation, villous morphology, and apoptotic and proliferative mediators were measured. Apoptosis-related gene expression and the bile acid pool were determined in separate experiments up to 6 h after burn. Gut epithelial cell apoptosis as well as apoptosis-related genes were increased after the thermal injury, whereas bile acid secretion was significantly decreased (P < 0.05). IGF-I/IGFBP-3 significantly improved villous height and cells per villous by decreasing small bowel epithelial cell apoptosis and increasing proliferation (P < 0.05). Decreased apoptosis was associated with decreased Fas, Fas-ligand, and TNF when compared with saline (P < 0.05). A severe thermal injury caused an up-regulation of apoptosis and apoptosis-related genes and down-regulation of bile acid secretion. IGF-I/IGFBP-3 decreases small bowel epithelial cell apoptosis through down-regulation of the Fas pathway, which improves gut mucosal integrity after a severe thermal injury.
Inverse dynamic optimization is a popular method for predicting muscle and joint reaction forces within human musculoskeletal joints. However, the traditional formulation of the optimization method ...does not include the joint reaction moment in the moment equilibrium equation, potentially violating the equilibrium conditions of the joint. Consequently, the predicted muscle and joint reaction forces are coordinate system-dependent. This paper presents an improved optimization method for the prediction of muscle forces and joint reaction forces. In this method, the location of the rotation center of the joint is used as an optimization variable, and the moment equilibrium equation is formulated with respect to the joint rotation center to represent an accurate moment constraint condition. The predicted muscle and joint reaction forces are independent of the joint coordinate system. The new optimization method was used to predict muscle forces of an elbow joint. The results demonstrated that the joint rotation center location varied with applied loading conditions. The predicted muscle and joint reaction forces were different from those predicted by using the traditional optimization method. The results further demonstrated that the improved optimization method converged to a minimum for the objective function that is smaller than that reached by using the traditional optimization method. Therefore, the joint rotation center location should be involved as a variable in an inverse dynamic optimization method for predicting muscle and joint reaction forces within human musculoskeletal joints.
We determined the prognostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for patients with treated lung cancer.
We examined patients who underwent FDG PET after ...first-line treatment for non-small cell lung cancer. FDG PET results were correlated with survival rates to determine whether FDG PET findings were predictive of outcomes.
After initial therapy, 113 patients with non-small cell lung cancer underwent FDG PET. One hundred patients had positive FDG PET results and a median survival of 12 months (95% confidence interval, 9.2-15.4). Thirteen patients had negative FDG PET results, and 11 (85%) of these patients are still living at a median follow-up of 34 months. The difference in survival for patients with positive and negative FDG PET results was statistically significant (p = 0.002).
FDG PET has prognostic value and strongly correlates with survival rates of patients with treated lung cancer. Patients with positive FDG PET results have a significantly worse prognosis than patients with negative results. Additionally, FDG PET may be helpful in guiding therapeutic treatments.
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