This prospective trial was designed to compare the performance characteristics of five different screening tests in parallel for the detection of advanced colonic neoplasia: CT colonography (CTC), ...colonoscopy (OC), flexible sigmoidoscopy (FS), faecal immunochemical stool testing (FIT) and faecal occult blood testing (FOBT).
Average risk adults provided stool specimens for FOBT and FIT, and underwent same-day low-dose 64-multidetector row CTC and OC using segmentally unblinded OC as the standard of reference. Sensitivities and specificities were calculated for each single test, and for combinations of FS and stool tests. CTC radiation exposure was measured, and patient comfort levels and preferences were assessed by questionnaire.
221 adenomas were detected in 307 subjects who completed CTC (mean radiation dose, 4.5 mSv) and OC; 269 patients provided stool samples for both FOBT and FIT. Sensitivities of OC, CTC, FS, FIT and FOBT for advanced colonic neoplasia were 100% (95% CI 88.4% to 100%), 96.7% (82.8% to 99.9%), 83.3% (95% CI 65.3% to 94.4%), 32% (95% CI 14.9% to 53.5) and 20% (95% CI 6.8% to 40.7%), respectively. Combination of FS with FOBT or FIT led to no relevant increase in sensitivity. 12 of 45 advanced adenomas were smaller than 10 mm. 46% of patients preferred CTC and 37% preferred OC (p<0.001).
High-resolution and low-dose CTC is feasible for colorectal cancer screening and reaches sensitivities comparable with OC for polyps >5 mm. For patients who refuse full bowel preparation and OC or CTC, FS should be preferred over stool tests. However, in cases where stool tests are performed, FIT should be recommended rather than FOBT.
During untreated ventricular fibrillation (VF), before CPR is applied, different bodily systems deteriorate at different rates. This paper describes the times when the EEG disappears, when ...respiratory arrest occurs, and when PD-PEA occurs. It also describes the frequency of VF waves over a 7-min period and how the frequency increases with good CPR.
Modeling and analysis of calcium bromide hydrolysis Lottes, Steven A.; Lyczkowski, Robert W.; Panchal, Chandrakant B. ...
International journal of hydrogen energy,
05/2009, Letnik:
34, Številka:
9
Journal Article, Conference Proceeding
Recenzirano
The main focus of this paper is the modeling, simulation, and analysis of the calcium bromide hydrolysis reactor stage in the calcium–bromine thermochemical water-splitting cycle for nuclear hydrogen ...production. One reactor concept is to use a spray of calcium bromide into steam, in which the heat of fusion supplies the heat of reaction. Droplet models were built up in a series of steps incorporating various physical phenomena, including droplet flow, heat transfer, phase change, and reaction, separately. Given the large heat reservoir contained in a pool of molten calcium bromide that allows bubbles to rise easily, using a bubble column reactor for the hydrolysis appears to be a feasible and promising alternative to the spray reactor concept. The two limiting cases of bubble geometry, spherical and spherical-cap, are considered in the modeling. Results for both droplet and bubble modeling with COMSOL MULTIPHYSICS™ are presented, with recommendations for the path forward.
Purpose
A prospective, multicenter post-market surveillance study in Japan evaluated the 2-year safety and effectiveness of the DES in real-world patients with complex femoropopliteal artery lesions.
...Methods
There were no exclusion criteria, and consecutive symptomatic patients with femoropopliteal lesions treated with the DES were enrolled in the study. Clinically driven target lesion revascularization (TLR) was defined as reintervention performed for > 50% diameter stenosis after recurrent clinical symptoms of peripheral arterial disease. Clinical benefit was defined as freedom from persistent or deteriorating ischemic symptoms. Patency was evaluated by duplex ultrasound where physicians considered this standard of care.
Results
In this study, 905 patients were enrolled at 95 institutions in Japan. There were numerous comorbidities including a high incidence of diabetes (58.8%) and chronic kidney disease (43.6%). Additionally, 21.4% of patients were classified with critical limb ischemia. Lesions were complex, with an average length of 14.6 ± 9.6 cm (range 0.5–40 cm), 41.5% total occlusions, and 18.7% in-stent restenosis. In total, 1861 DES were placed in 1080 lesions. Two-year follow-up was obtained for > 90% of eligible patients. Freedom from TLR was 83.7%, and clinical benefit was 80.0% through 2 years. The 2-year primary patency rate was 70.3%. Rutherford classification significantly improved (
p
< 0.01), with approximately 80% of patients classified as Rutherford class 0 or 1 at 2 years.
Conclusion
Despite more challenging lesion characteristics, 2-year results from the current study are similar to outcomes from the previous Zilver PTX studies, confirming the efficacy of the Zilver PTX DES in a complicated femoropopliteal lesion (Zilver PTX Post-Market Study in Japan; NCT02254837).
Level of Evidence
Post-market surveillance study, Level III.
Purpose Although gum chewing while walking has been reported to increase walking speed and heart rate, its effect on energy expenditure remains unclear. The purpose of the present study was to ...investigate the effects of gum chewing while walking on fat oxidation, energy expenditure, and different walking parameters. Participants and Methods This randomized crossover study included 10 males and 5 females who walked for 15 min at their own pace while chewing 2 pieces of gum in the gum trial or while eating 2 tablets in the control trial. A wearable metabolic system, heart rate monitor, and pedometer measured fat oxidation, energy expenditure, heart rate, step count, and walking distance. Walking speed and stride length were also calculated. Results The energy expenditure, fat oxidation and heart rate were significantly higher during the gum trial than during the control trial. Significant increases were observed in the step count, walking distance, and walking speed but not in the stride length. Conclusion Our results suggest that gum chewing affects sympathetic nervous system activity and walking rhythm with a consequent improvement in the health-related effects of walking, which in turn helps to maintain weight. These findings may play a role in preventing the gradual age-related weight gain that predisposes to obesity.
Seed particles are added to a high temperature reacting flow to achieve the desired electric conductivity for magnetohydrodynamic (MHD) power generation. The evaporation rate of the see particles and ...the uniformity of the seed vapor distribution in the reacting flow are major factors affecting the performance of the MHD system. An integral reacting flow (IRF) computer code was used to calculate the multi-phase flow characteristics in an MHD combustor and predict the optimum operating conditions of the combustor. The IRF code is a general hydrodynamics computer code for multi-phase, two dimensional, steady state, turbulent, and reacting flows, based on mass, momentum, and energy conservation laws. A unique integral reaction submodel in the IRF code enhances numerical convergence while preserving the major physical effects of the complex combustion processes. The combustor is a rectangular channel in which a mixture of fuel gas and seed particles enters from one end and exits at the other, while the oxidizer is injected from the sides. The major findings of a parametric study included: (1) the seed particle evaporation rate varies for different oxidizer injection angles; (2) the optimal evaporation rate was found at an injection angle around 130°; (3) the seed particle size had a major effect on particle dispersion and vapor mixing; (4) seed particles with a diameter of 34 μm or larger were only partially vaporized in the combustor, and the seed vapor distribution at the combustor exit was highly non-uniform; and (5) significant particle deposition was found on the side walls upstream of the oxidizer injection slots. Theoretical predictions were in general agreement with experimental trends.
Purpose This study examined the effects of gum chewing while walking on physical and physiological functions. Subjects and Methods This study enrolled 46 male and female participants aged 21–69 ...years. In the experimental trial, participants walked at natural paces for 15 minutes while chewing two gum pellets after a 1-hour rest period. In the control trial, participants walked at natural paces for 15 minutes after ingesting powder containing the same ingredient, except the gum base, as the chewing gum. Heart rates, walking distances, walking speeds, steps, and energy expenditure were measured. Results Heart rates during walking and heart rate changes (i.e., from at rest to during walking) significantly increased during the gum trial compared with the control trial. Walking distance, walking speed, walking heart rate, and heart rate changes in male participants and walking heart rate and heart rate changes in female participants were significantly higher during the gum trial than the control trial. In middle-aged and elderly male participants aged ≥40 years, walking distance, walking speed, steps, and energy expenditure significantly increased during the gum trial than the control trial. Conclusion Gum chewing while walking measurably affects physical and physiological functions.