69 research outputs found
Pore Narrowing and Formation of Ultrathin Yttria-Stabilized Zirconia Layers in Ceramic Membranes by Chemical Vapor Deposition/Electrochemical Vapor Deposition
Chemical vapor deposition (CVD) and electrochemical vapor deposition (EVD) have been applied to deposit yttria-stabilized-zirconia (YSZ) on porous ceramic media. The experimental results indicate that the location of YSZ deposition can be varied from the surface of the substrates to the inside of the substrates by changing the CVD/EVD experimental conditions, i.e., the concentration ratio of the reactant vapors. The deposition width is strongly dependent on the deposition temperature used. The deposition of YSZ inside the pores resulted in pore narrowing and eventually pore closure, which was measured by using permpor-ometry. However, deposition of YSZ on top of porous ceramic substrates (outside the pores) did not result in a reduction of the average pore size. Ultrathin, dense YSZ layers on porous ceramic substrates can be obtained by suppressing the EVD layer growth process after pore closure
Randomized controlled trials of antibiotic prophylaxis in severe acute pancreatitis:Relationship between methodological quality and outcome
AIM: To evaluate the methodological quality of randomized controlled trials (RCTs) of systemic antibiotic prophylaxis in severe acute pancreatitis in relation to outcome. METHODS: The MEDLINE, EMBASE and Cochrane databases were searched for RCTs that studied the effectiveness of systemic antibiotic prophylaxis in severe acute pancreatitis. A meta-analysis was performed with a random effects model. Methodological quality was quantified by a previously published scoring system (range 0-17 points). RESULTS: Six studies, with a total of 397 participants, obtained a methodological score of at least 5 points and were included. Systemic antibiotic prophylaxis had no significant effect on infection of pancreatic necrosis (absolute risk reduction (ARR) 0.055; 95% CI -0.084 to 0.194) and mortality (ARR 0.058, 95% CI -0.017 to 0.134). Spearman correlation showed an inverse association between methodological quality and ARR for mortality (correlation coefficient -0.841, p = 0.036). CONCLUSIONS: The inverse relationship between methodological quality and impact of antibiotic prophylaxis on mortality emphasizes the importance of high-quality RCTs. At present, adequate evidence for the routine use of antibiotic prophylaxis in severe acute pancreatitis is lackin
Nature knows better? Nature as exemplar and/or inspiration?
The arising of the industrial society and the growth of human population have been main causes of resource depletion, climate change and the decline of ecosystems. Industrial systems and technologies have brought economic and public health progress, leading to an unprecedented population in relatively good conditions. But often, the new technologies that enabled this development turned out not to be the miracle solutions that they had been claimed to be: plastics contained toxics and caused world-wide litter, industrially processed food turned out to be a threat to public health, information and communication technologies provided a wealth of information but also threatened democratic society, and military technologies to secure freedom threatened humanity’s very existence. In reaction, there was a tendency to return to natural products and production processes. ‘Industry’ and ‘Modern Technology’ became suspect. Slogans emerged that emphasized the value of nature: ‘Nature knows better’ emphasizing healthier products without synthetic chemicals and “Nature does not produce any waste” criticizing the whole industrial society. Many of these slogans are in fact not verifiable empirical statements, and some of them are erroneous. Hence, ‘natural’ and ‘nature derived’ products and production processes are not a priori to be preferred above man-made products as the sustainable solution. Why are man-made products and processes not considered to be natural like the ones made by other animals? The first question that this paper addresses is how to assess ‘natural’-, ‘nature derived’- and ‘classic’ solutions to design challenges. In the first part of the paper, it is shown by various short case studies that design solutions from nature have survived long periods of selection pressure, which implies that they are in balance with their natural environment. The vast number of specific niches that ecosystems provide has created an abundance of natural design solutions. Hence, in the second part, the question will be addressed if the study of ‘natural principles’ can help industrial designers to think outside the box. Understanding biological analogies remains difficult for design students. Preliminary empirical research showed students using these, intentionally or unintentionally, copied aspects which are often misinterpreted into their design, i.e. blindly copying form while leaving out process or system. Biomimicry education offers new and compelling insights to measure and evaluate products, aiming to improve the sustainability score. This study reviews basic steps on how biomimicry could improve design education
Non-alcoholic fatty liver disease: identical etiologic factors in patients with type 1 and type 2 diabetes
Aims: To compare NAFLD prevalence, distribution and its etiologic determinants in patients with type 1 diabetes (T1D) and type 2 diabetes (T2D). Methods: In this cross-sectional study, NAFLD was evaluated by transient elastography in adult outpatients with T1D and T2D. NAFLD was defined as hepatic steatosis with or without fibrosis. Associations between insulin resistance related factors and NAFLD and advanced fibrosis (≥ F3) were explored in T1D and T2D separately, using multivariate logistic regression models. Interaction analysis was performed to compare the associations in patients with T1D and T2D. Results: One hundred and fifty patients with T1D (mean age 47 years, male 55%, mean diabetes duration 25 years, median BMI 25 kg/m2) and 100 patients with T2D (median age 67 years, male 56%, median diabetes duration 17 years, mean BMI 30 kg/m2) were included. NAFLD prevalence was 20% in patients with T1D and 76% in patients with T2D. Advanced fibrosis prevalence was 2.0% in patients with T1D and 22% in patients with T2D. In both patients with T1D and T2D, waist circumference, BMI and metabolic syndrome were positively associated, and estimated insulin sensitivity was negatively associated with the presence of NAFLD, adjusted for age, sex and diabetes duration. There was no effect modification by diabetes type for any of these associations. Conclusions: Despite differences in population characteristics and pathophysiology between T1D and T2D, insulin resistance related factors are similarly associated with NAFLD in both groups
Disease burden in primary sclerosing cholangitis in the Netherlands: A long-term follow-up study
Background & Aims: Primary sclerosing cholangitis (PSC) is a progressive, cholestatic liver disease which greatly impacts the lives of individuals. Burden of disease due to shortened life expectancy and impaired quality of life is ill-described. The aim of this study was to assess long-term disease burden in a large population-based registry with regard to survival, clinical course, quality adjusted life years (QALYs), medical consumption and work productivity loss. Methods: All PSC patients living in a geographically defined area covering ~50% of the Netherlands were included, together with patients from the three liver transplant centres. Survival was estimated by competing risk analysis. Proportional shortfall of QALYs during disease course was measured relative to a matched reference cohort using validated questionnaires. Work productivity loss and medical consumption were evaluated over time. Results: A total of 1208 patients were included with a median follow-up of 11.2 year. Median liver transplant-free survival was 21.0 years. Proportional shortfall of QALYs increased to 48% >25 years after diagnosis. Patients had on average 12.4 hospital contact days among which 3.17 admission days per year, annual medical costs were €12 169 and mean work productivity loss was 25%. Conclusions: Our data quantify for the first time disease burden in terms of QALYs lost, clinical events, medical consumption, costs as well as work productivity loss, and show that all these are substantial and increase over time
Secular trends: a ten-year comparison of the amount and type of physical activity and inactivity of random samples of adolescents in the Czech Republic
BACKGROUND:
An optimal level of physical activity (PA) in adolescence influences the level of PA in adulthood. Although PA declines with age have been demonstrated repeatedly, few studies have been carried out on secular trends. The present study assessed levels, types and secular trends of PA and sedentary behaviour of a sample of adolescents in the Czech Republic.
METHODS:
The study comprised two cross-sectional cohorts of adolescents ten years apart. The analysis compared data collected through a week-long monitoring of adolescents' PA in 1998-2000 and 2008-2010. Adolescents wore either Yamax SW-701 or Omron HJ-105 pedometer continuously for 7 days (at least 10 hours per day) excluding sleeping, hygiene and bathing. They also recorded their number of steps per day, the type and duration of PA and sedentary behaviour (in minutes) on record sheets. In total, 902 adolescents (410 boys; 492 girls) aged 14-18 were eligible for analysis.
RESULTS:
Overweight and obesity in Czech adolescents participating in this study increased from 5.5% (older cohort, 1998-2000) to 10.4% (younger cohort, 2008-2010). There were no inter-cohort significant changes in the total amount of sedentary behaviour in boys. However in girls, on weekdays, there was a significant increase in the total duration of sedentary behaviour of the younger cohort (2008-2010) compared with the older one (1998-2000). Studying and screen time (television and computer) were among the main sedentary behaviours in Czech adolescents. The types of sedentary behaviour also changed: watching TV (1998-2000) was replaced by time spent on computers (2008-2010).The Czech health-related criterion (achieving 11,000 steps per day) decreased only in boys from 68% (1998-2000) to 55% (2008-2010). Across both genders, 55%-75% of Czech adolescents met the health-related criterion of recommended steps per day, however less participants in the younger cohort (2008-2010) met this criterion than in the older cohort (1998-2000) ten years ago. Adolescents' PA levels for the monitored periods of 1998-2000 and 2008-2010 suggest a secular decrease in the weekly number of steps achieved by adolescent boys and girls.
CONCLUSION:
In the younger cohort (2008-2010), every tenth adolescent was either overweight or obese; roughly twice the rate when compared to the older cohort (1998-2000). Sedentary behaviour seems relatively stable across the two cohorts as the increased time that the younger cohort (2008-2010) spent on computers is compensated with an equally decreased time spent watching TV or studying. Across both cohorts about half to three quarters of the adolescents met the health-related criterion for achieved number of steps. The findings show a secular decrease in PA amongst adolescents. The significant interaction effects (cohort × age; and cohort × gender) that this study found suggested that secular trends in PA differ by age and gender
A many-analysts approach to the relation between religiosity and well-being
The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported β=0.120). For the second research question, this was the case for 65% of the teams (median reported β=0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates
A Many-analysts Approach to the Relation Between Religiosity and Well-being
The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N = 10, 535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported β = 0.120). For the second research question, this was the case for 65% of the teams (median reported β = 0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates
- …