Theory of twisted nonuniformly heated bars

Nonlineary distributed stresses in twisted nonuniformly heated bars of arbitrary cross section are calculated taking into account various elasticity parameters. The approximate theory is shown to be sufficiently general and accurate by comparison with experimental data

Bleeding Risk, Physical Functioning, and Non-use of Anticoagulation Among Patients with Stroke and Atrial Fibrillation

Background: Atrial fibrillation (AF) is common among people with stroke. Anticoagulation medications can be used to manage the deleterious impact of AF after stroke, however may not be prescribed due to concerns about post-stroke falls and decreased functioning. Thus, the purpose of this study was to identify, among people with stroke and AF, predictors of anticoagulation prescription at hospital discharge. Methods: This is a secondary analysis of a retrospective cohort study of data retrieved via medical records, including: National Institutes of Health Stroke Scale score; Functional Independence Measure (FIM) motor score (motor or physical function); ambulation on 2nd day of hospitalization; Morse Falls Scale (fall risk); and HAS-BLED score (Hypertension; Abnormal renal and liver function; Stroke; Bleeding; Labile INRs; Elderly > 65; and Drugs or alcohol). Data analyses included bivariate comparisons between people with and without anticoagulation at discharge. Logistic-regression modeling was used to assess predictors of discharge anti-coagulation. Results: There were 334 subjects included in the analyses, average age was 75 years old. Anticoagulation was prescribed at discharge for 235 (70%) of patients. In the adjusted regression analyses, only the FIM motor score (adjusted OR = 1.015, 95%CI 1.001-1.028) and the HAS-BLED score (adjusted OR = 0.36, 95%CI 0.22-0.58) were significantly associated with anticoagulation prescription at discharge. Conclusion: It appears that in this sample, post-stroke anti-coagulation decisions appear to be made based on clinical factors associated with bleed risk and motor deficits or physical functioning. However, opportunities may exist for improving clinician documentation of specific reasoning for non-anticoagulation prescription

Outcomes associated with bacteremia in the setting of methicillin-resistant Staphylococcus aureus pneumonia: A retrospective cohort study

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) remains an important pathogen in pneumonia. Bacteremia may secondarily complicate MRSA pneumonia. The epidemiology and outcomes associated with bacteremia in the setting of MRSA pneumonia are unknown. We sought to describe the prevalence of bacteremia in MRSA pneumonia and its impact on hospital mortality and length of stay (LOS). METHODS: We conducted a single-center retrospective cohort study (2008–2013) including adult patients hospitalized with pneumonia caused by MRSA. We defined pneumonia based on clinical criteria and all cases were culture confirmed. MRSA bacteremia was identified based on positive blood cultures. Pneumonia was categorized as either community-onset (CO, occurring at presentation or within 2 days of admission) or hospital-onset (HO, occurring > 2 days after admission). We compared bacteremic and non-bacteremic groups with respect to their demographic and clinical characteristics and outcomes. A logistic regression and a generalized linear model (GLM) were constructed to examine the impact of bacteremia on hospital mortality and post-pneumonia onset LOS, respectively. RESULTS: Among the 765 patients with MRSA pneumonia (33.1 % CO), 93 (12.2 %) had concurrent bacteremia (37.6 % CO). Patients with bacteremia were similar to non-bacteremic subjects based on demographic and clinical characteristics with the exception of frequency of a hospitalization within prior 180 days (48.4 % bacteremic and 37.7 % non-bacteremic, p = 0.047), prevalence of chronic liver disease (17.2 % vs. 9.5 %, p = 0.030), and the mean APACHE II score at the onset of pneumonia (17.5 ± 6.0 vs. 16.1 ± 6.0, p = 0.045). Both unadjusted mortality (33.7 % vs. 23.8 %, p = 0.067) and median post-pneumonia LOS (18.2 vs. 12.2 days, p < 0.001) were greater in the bacteremic than the non-bacteremic group. In a logistic regression, bacteremia showed a trend toward an association with increased mortality (odds ratio 1.56, 95 % confidence interval 0.93 to 2.61). Concomitant bacteremia was independently associated with a 10.3-day increase in the post-pneumonia hospital LOS (95 % confidence interval 6.7 to 13.9 days). CONCLUSIONS: Concurrent bacteremia occurred with moderate frequency in the setting of hospitalization with MRSA pneumonia. Although bacteremia did not appear to independently impact mortality, this was likely due to our study’s limited sample size. However, bacteremia complicating MRSA pneumonia added between 1 and 2 weeks to the hospital LOS

Effect of tangential swirl air inlet angle on the combustion efficiency of a hybrid powder-solid ramjet

A new ramjet configuration using powder and solid fuel as propellant is investigated, namely, hybrid powder-solid ramjet (HPSR). Boron particles were used as the powder in this study. In order to improve combustion efficiency of boron and simplify the engine structure, a tangential swirl air inlet is adopted on the HPSR. Ignition model based on the multi-layer oxide structure and Global reaction combustion model of boron particles, the Lagrangian particle trajectory model and the realizable k-ε turbulence model were implemented to calculate three-dimensional two-phase flow and combustion in the HPSR with the different tangential air inlet angles (0°,5°, 10°, 15°, 20°, 25°). The effects of tangential air inlet angles on the ignition and combustion of boron were analyzed. The results show that when the tangential swirl air inlet angle is 10°, the combustion efficiency of boron particles and the total combustion efficiency of engine are the highest; the temperature distribution in the second combustion chamber is uniform, and the ignition distance of particles is small, for the HPSR configuration tested

Telavancin for hospital-acquired pneumonia: Clinical response and 28-day survival

U.S. Food and Drug Administration draft guidance for future antibiotic clinical trials of bacterial nosocomial pneumonia recommends the use of diagnostic criteria according to American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines and the use of a primary endpoint of 28-day all-cause mortality. The effect of applying these guidelines on outcomes of phase III nosocomial pneumonia studies of telavancin was evaluated in a post hoc analysis. ATS/IDSA criteria were applied in a blind fashion to the original all-treated (AT) group. Clinical cure rates at final follow-up were determined in the refined AT and clinically evaluable (CE) groups (ATS/IDSA-AT and ATS/IDSA-CE, respectively). The exploratory endpoint of 28-day survival was evaluated for the ATS/IDSA-AT group. Noninferiority of telavancin versus vancomycin was demonstrated, with similar cure rates in the ATS/IDSA-AT (59% versus 59%) and ATS/IDSA-CE (83% versus 80%) groups. Cure rates favored telavancin in ATS/IDSA-CE patients where Staphylococcus aureus was the sole pathogen (86% versus 75%). Overall, 28-day survival rates were similar in the telavancin (76%) and vancomycin (77%) groups but lower in telavancin-treated patients with preexisting moderate-to-severe renal impairment (creatinine clearance [CL(CR)] of <50 ml/min). Telavancin should be administered to patients with moderate-to-severe renal impairment only if treatment benefit outweighs the risk or if no suitable alternatives are available