1,506 research outputs found
Cavitation erosion of WC-Co
Bibliography: pages 68-70.An investigation involving the vibratory cavitation erosion of WC-Co alloys was undertaken in order to determine the mechanisms of material removal. Nineteen grades of WC-Co alloys were studied. These alloys had been previously characterised according to microstructural and mechanical properties. Further characterisation by way of Young's modulus and density of the materials was undertaken. An investigation of the i nfluence of various parameters on cavitation erosion established a binder content dependence on erosion. For two grain sizes, erosion was found to increase to a maximum at 12 vo1-% binder content (1.8 Ī¼m grain size) and 23 vol-% binder (2.8 Ī¼m grain size). The main mode of material removal was found to be cobalt removal followed by WC grain pull-out. In high binder content alloys, cobalt removal was predominant with little loss of WC grains. X-ray diffraction showed that the allotropic phase transformation of the binder under cavitational attack was beneficial to the erosion resistance of these alloys. The erosion of low binder content alloys was controlled by the contiguity of the WC skeleton. Maximum erosion occurred at binder contents which corresponded to the combination of a fragile WC skeleton and a small volume of available cobalt for strain induced transformation
Designing the eatwell week: the application of eatwell plate advice to weekly food intake
<p>To develop a menu and resource to illustrate to consumers and health professionals what a healthy balanced diet looks like over the course of a week.</p>
<p>Development and analysis of an illustrative 7 d āeatwell weekā menu to meet current UK recommendations for nutrients with a Dietary Reference Value, with a daily energy base of 8368 kJ (2000 kcal). Foods were selected using market research data on meals and snacks commonly consumed by UK adults. Analysis used the food composition data set from year 1 (2008) of the UK National Diet and Nutrition Survey rolling programme. The eatwell week menu was developed using an iterative process of nutritional analysis with adjustments made to portion sizes and the inclusion/exclusion of foods in order to achieve the target macronutrient composition.</p>
<p>Three main meals and two snacks were presented as interchangeable within the weekdays and two weekend days to achieve adult food and nutrient recommendations. Main meals were based on potatoes, rice or pasta with fish (two meals; one oily), red meat (two meals), poultry or vegetarian accompaniments. The 5-a-day target for fruit and vegetables (range 5ā6Ā·7 portions) was achieved daily. Mean salt content was below recommended maximum levels (<6 g/d). All key macro- and micronutrient values were achieved.</p>
<p>Affordable foods, and those widely consumed by British adults, can be incorporated within a 7 d healthy balanced menu. Future research should investigate the effect of using the eatwell week on adultsā dietary habits and health-related outcomes.</p>
Weight management: a comparison of existing dietary approaches in a work-site setting
<b>OBJECTIVES:</b> (1) To compare the effectiveness a 2512 kJ (600 kcal) daily energy deficit diet (ED) with a 6279 kJ (1500 kcal) generalized low-calorie diet (GLC) over a 24 week period (12 weeks weight loss plus 12 weeks weight maintenance). (2) To determine if the inclusion of lean red meat at least five times per week as part of a slimming diet is compatible with weight loss in comparison with a diet that excludes lean red meat.
DESIGN: Randomized controlled trial.
<b>SETTING:</b> Large petrochemical work-site.
<b>PARTICIPANTS:</b> One-hundred and twenty-two men aged between 18 and 55 y.
<b>MAIN OUTCOME MEASURES:</b> Weight loss and maintenance of weight loss.
<b>INTERVENTION:</b> Eligible volunteers were randomized to one of the four diet=meat combinations (ED meat, ED no meat, GLC meat, GLC no meat). One-third of subjects in each diet/meat combination were randomized to an initial control period prior to receiving dietary advice. All subjects attended for review every 2 weeks during the weight loss period. For the 12 week structured weight maintenance phase, individualized energy prescriptions were re-calculated for the ED group as 1.4 (activity factor)x basal metabolic rate. Healthy eating advice was reviewed with subjects in the GLC group. All subjects were contacted by electronic mail at 2 week intervals and anthropometric and dietary information requested.
<b>RESULTS:</b> No difference was evident between diet groups in mean weight loss at 12 weeks (4.3 (s.d. 3.4) kg ED group vs 5.0 (s.d. 3.5) kg GLC group, P=0.34). Mean weight loss was closer to the intended weight loss in the 2512 kJ (600 kcal) ED group. The dropout rate was also lower than the GLC group. The inclusion of lean red meat in the diet on at least five occasions per week did not impair weight loss. Mean weight gain following 12 weeks weight maintenance was Ć¾1.1 (s.d. 1.8) kg, P<0.0001.
No differences were found between groups.
<b>CONCLUSIONS:</b> This study has shown that the individualized 2512 kJ (600 kcal) ED approach was no more effective in terms of weight loss than the 6279 kJ (1500 kcal) GLC approach. However the ED approach might be considered preferable as compliance was better with this less demanding prescription. In terms of weight loss the elimination of red meat from the diet is unnecessary. The weight maintenance intervention was designed as a low-input approach, however weight regain was significant and weight maintenance strategies require further development
Philosophy, Psychology, Physics and Practice of Ki
Ki (in Japanese) or Qi (in Chinese) is the key concept in Eastern medicine, Eastern philosophy, as well as in martial arts. We explain the philosophical and psychological background of Ki. We emphasize that the unique aspects of Eastern philosophy are ānon-linearityā and āholisticā approach. We then present physics aspect of Ki. Our experiments demonstrated that a āKi-beamā carries āentropyā (or information), which is different from āenergyā. We introduce our experience of having taught Ki to 37 beginners in the United States through the Nishino Breathing Method. If beginners had martial arts training or a strong background in music or dance, about half of them could sense Ki within 10 weeks (1 h class per week) of practice
Applicability of a noise-based model to estimate in-traffic exposure to black carbon and particle number concentrations in different cultures
Depinning transition and thermal fluctuations in the random-field Ising model
We analyze the depinning transition of a driven interface in the 3d
random-field Ising model (RFIM) with quenched disorder by means of Monte Carlo
simulations. The interface initially built into the system is perpendicular to
the [111]-direction of a simple cubic lattice. We introduce an algorithm which
is capable of simulating such an interface independent of the considered
dimension and time scale. This algorithm is applied to the 3d-RFIM to study
both the depinning transition and the influence of thermal fluctuations on this
transition. It turns out that in the RFIM characteristics of the depinning
transition depend crucially on the existence of overhangs. Our analysis yields
critical exponents of the interface velocity, the correlation length, and the
thermal rounding of the transition. We find numerical evidence for a scaling
relation for these exponents and the dimension d of the system.Comment: 6 pages, including 9 figures, submitted for publicatio
Street-view greenspace exposure and objective sleep characteristics among children
Greenspace may benefit sleep by enhancing physical activity, reducing stress or air pollution exposure. Studies on greenspace and children's sleep are limited, and most use satellite-derived measures that do not capture ground-level exposures that may be important for sleep. We examined associations of street view imagery (SVI)-based greenspace with sleep in Project Viva, a Massachusetts pre-birth cohort. We used deep learning algorithms to derive novel metrics of greenspace (e.g., %trees, %grass) from SVI within 250m of participant residential addresses during 2007ā2010 (mid-childhood, mean age 7.9 years) and 2012ā2016 (early adolescence, 13.2y) (N = 533). In early adolescence, participants completed >5 days of wrist actigraphy. Sleep duration, efficiency, and time awake after sleep onset (WASO) were derived from actigraph data. We used linear regression to examine cross-sectional and prospective associations of mid-childhood and early adolescence greenspace exposure with early adolescence sleep, adjusting for confounders. We compared associations with satellite-based greenspace (Normalized Difference Vegetation Index, NDVI). In unadjusted models, mid-childhood SVI-based total greenspace and %trees (per interquartile range) were associated with longer sleep duration at early adolescence (9.4 min/day; 95%CI:3.2,15.7; 8.1; 95%CI:1.7,14.6 respectively). However, in fully adjusted models, only the association between %grass at mid-childhood and WASO was observed (4.1; 95%CI:0.2,7.9). No associations were observed between greenspace and sleep efficiency, nor in cross-sectional early adolescence models. The association between greenspace and sleep differed by racial and socioeconomic subgroups. For example, among Black participants, higher NDVI was associated with better sleep, in neighborhoods with low socio-economic status (SES), higher %grass was associated with worse sleep, and in neighborhoods with high SES, higher total greenspace and %grass were associated with better sleep time. SVI metrics may have the potential to identify specific features of greenspace that affect sleep
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Patient-Reported Satisfaction and Study Drug Discontinuation: Post-Hoc Analysis of Findings from ROCKET AF.
IntroductionPatient-reported outcomes (PROs) and satisfaction endpoints are increasingly important in clinical trials and may be associated with treatment adherence. In this post hoc substudy from ROCKET AF, we examined whether patient-reported satisfaction was associated with study drug discontinuation.MethodsROCKET AF (nā=ā14,264) compared rivaroxaban with warfarin for prevention of stroke and systemic embolism in patients with atrial fibrillation. We analyzed treatment satisfaction scores: the Anti-Clot Treatment Scale (ACTS) and Treatment Satisfaction Questionnaire for Medication version II (TSQM II). We compared satisfaction with study drug between the two treatment arms, and examined the association between satisfaction and patient-driven study drug discontinuation (stopping study drug due to withdrawal of consent, noncompliance, or loss to follow-up).ResultsA total of 1577 (11%) patients participated in the Patient Satisfaction substudy; 1181 (8.3%) completed both the ACTS and TSQM II 4Ā weeks after starting study drug. Patients receiving rivaroxaban did not experience significant differences in satisfaction compared with those receiving warfarin. During a median follow-up of 1.6Ā years, 448 premature study drug discontinuations occurred (213 rivaroxaban group; 235 warfarin group), of which 116 (26%) were patient-driven (52 [24%] rivaroxaban group; 64 [27%] warfarin group). No significant differences were observed between satisfaction level and rates of patient-driven study drug discontinuation.ConclusionsStudy drug satisfaction did not predict rate of study drug discontinuation. No significant difference was observed between satisfaction with warfarin and rivaroxaban, as expected given the double-blind trial design. Although these results are negative, the importance of PRO data will only increase, and these analyses may inform future studies that explore the relationship between drug-satisfaction PROs, adherence, and clinical outcomes. CLINICALTRIALS.GOV: NCT00403767.FundingThe ROCKET AF trial was funded by Johnson & Johnson and Bayer
A comparison of aphasia therapy outcomes before and after a Very Early Rehabilitation programme following stroke
Background Very early aphasia rehabilitation studies have shown mixed results. Differences in therapy intensity and therapy type contribute significantly to the equivocal results. Aims To compare a standardized, prescribed very early aphasia therapy regimen with a historical usual care control group at therapy completion (4-5 weeks post-stroke) and again at follow-up (6 months). Methods & Procedures This study compared two cohorts from successive studies conducted in four Australian acute/sub-acute hospitals. The studies had near identical recruitment, blinded assessment and data-collection protocols. The Very Early Rehabilitation (VER) cohort (N = 20) had mild-severe aphasia and received up to 20 1-h sessions of impairment-based aphasia therapy, up to 5 weeks. The control cohort (n = 27) also had mild-severe aphasia and received usual care (UC) therapy for up to 4 weeks post-stroke. The primary outcome measure was the Aphasia Quotient (AQ) and a measure of communicative efficiency (DA) at therapy completion. Outcomes were measured at baseline, therapy completion and 6 months post-stroke and were compared using Generalised Estimating Equations (GEE) models. Outcomes & Results After controlling for initial aphasia and stroke disability, the GEE models demonstrated that at the primary end-point participants receiving VER achieved 18% greater recovery on the AQ and 1.5% higher DA scores than those in the control cohort. At 6 months, the VER participants maintained a 16% advantage in recovery on the AQ and 0.6% more on DA scores over the control cohort participants. Conclusions & Implications A prescribed, impairment-based aphasia therapy regimen, provided daily in very early post-stroke recovery, resulted in significantly greater communication gains in people with mild-severe aphasia at completion of therapy and at 6 months, when compared with a historical control cohort. Further research is required to demonstrate large-scale and long-term efficacy
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