Development of a dynamic model for ice-on-coil external melt storage systems

Ice storage systems are commonly used to balance the intermittency of renewable energy and decrease the peak load by switching to off-peak hours. An adequate model is necessary to predict the behaviour of these systems. However, there is a scarce in detailed models available used to describe the performance of an ice storage evaporator and its use in a refrigeration cycle. Most existing models approximate the working principles with a steady analysis, not considering the sub cooling of ice and thickness distribution along the length. The developed model in this article uses a discretisation in length and radial direction together with an adapted thermal resistance matrix method to limit the calculation time. It has a great variability of boundary conditions and the ability to implement different types of refrigerants. The simulation results are in good agreement with the data of the manufacturer. The model shows that switching from R404A to R449A reduces the total electricity consumption

Die krugerfees van 1954 end die betekenis daarvan

Graag voldoen ek aan die versoek van die Redaksie om ’n paar indrukke van die Krugerfees weer te gee en om iets te sê oor die betekenis daarvan. Toe die Krugergenootskap aan die begin van 1953 verlof gekry het om die Krugerstandbeeld na Kerkplein te verskuiwe het ons dadelik besef dat ons aan die begin van die verwesenliking van ’n groot ideaal van dieAfrikanerdom s ta an en dat d a a r ’n groot volksfees in die verskiet lê

Hybrid distance water learning in Ethiopia

Ethiopia is among the countries with lowest water and sanitation coverage in Africa. To meet with the countries ambitious Millennium Development Goals there is an urgent need for capacity building in the water sector. This paper describes an innovative project that developed a new approach for practice based self-learning for local staff working at Woreda level. This approach combines conventional paper based Distance Learning with CD-rom and E-based learning, supported by a network of trainers and resource persons. The paper describes the approach and presents a way forward to support large numbers of sector staff learning to apply improved intervention strategies in their job environment

Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019 : a systematic analysis for the Global Burden of Disease Study 2019

In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and development investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding Bill & Melinda Gates Foundation

Facing homelessness

In facing homelessness we face the other, and in facing the other, we face ourselves. This book contributes to an emerging body of knowledge on street homelessness in the South African context. It is meant for researchers and scholars who are committed to finding solutions for street homelessness. It offers conceptual frameworks and practical guidelines for a liberative and transformative response to homelessness. It brings together authors from a wide range of disciplines, fusing the rigour of researchers, the vision of activists and the lived experience of practitioners. In this volume, the causes of street homelessness in South Africa today, and its different faces, are traced. It critiques singular solutions, and interrogates the political, institutional and moral failures that contribute to the systemic exclusion of homeless persons and other vulnerable populations from society. It proposes rights-based interventions as part of a radical re-imagination of how street homelessness can be ended, one person and one neighbourhood at a time. The analysis by the authors steer in the direction of new ways of doing and being that could demonstrate concrete, viable and sustainable alternatives to the exclusionary realities faced by homeless persons. It argues for solution-based approaches, aimed at radical forms of social inclusion and achieved through broad-based and creative collaborations by all spheres of society. In the face and presence of street homelessness – as one expression of urban vulnerability and deep socio-economic inequality – society is confronted with a clear political, institutional, moral and personal obligation. This volume calls for a reclamation of community in its most inclusionary, life-affirming and interdependent sense, asserting that we truly are well because of others, and we are unwell if others are. It is a call to reclaim our common humanity in the context of inclusive communities where all are equally welcome and bestowed with dignity and honour

Facing homelessness

In facing homelessness we face the other, and in facing the other, we face ourselves. This book contributes to an emerging body of knowledge on street homelessness in the South African context. It is meant for researchers and scholars who are committed to finding solutions for street homelessness. It offers conceptual frameworks and practical guidelines for a liberative and transformative response to homelessness. It brings together authors from a wide range of disciplines, fusing the rigour of researchers, the vision of activists and the lived experience of practitioners. In this volume, the causes of street homelessness in South Africa today, and its different faces, are traced. It critiques singular solutions, and interrogates the political, institutional and moral failures that contribute to the systemic exclusion of homeless persons and other vulnerable populations from society. It proposes rights-based interventions as part of a radical re-imagination of how street homelessness can be ended, one person and one neighbourhood at a time. The analysis by the authors steer in the direction of new ways of doing and being that could demonstrate concrete, viable and sustainable alternatives to the exclusionary realities faced by homeless persons. It argues for solution-based approaches, aimed at radical forms of social inclusion and achieved through broad-based and creative collaborations by all spheres of society. In the face and presence of street homelessness – as one expression of urban vulnerability and deep socio-economic inequality – society is confronted with a clear political, institutional, moral and personal obligation. This volume calls for a reclamation of community in its most inclusionary, life-affirming and interdependent sense, asserting that we truly are well because of others, and we are unwell if others are. It is a call to reclaim our common humanity in the context of inclusive communities where all are equally welcome and bestowed with dignity and honour

Construction and psychometric testing of the EMPATHIC questionnaire measuring parent satisfaction in the pediatric intensive care unit

Abstract PURPOSE: To construct and test the reliability and validity of the EMpowerment of PArents in THe Intensive Care (EMPATHIC) questionnaire measuring parent satisfaction in the pediatric intensive care unit (PICU). METHODS: Structured development and psychometric testing of a parent satisfaction-with-care instrument with the results of two cohorts of parents (n = 2,046) from eight PICUs in the Netherlands. RESULTS: In the first cohort, 667/1,055 (63%) parents participated followed by 551/991 (56%) parents in the second cohort. The empirical structure of the instrument was established by confirmatory factor analysis with the first sample of parents confirming 65 statements within five theoretically conceptualized domains: information, care and cure, organization, parental participation, and professional attitude. The standardized factor loadings were greater than 0.40 in 63 statements. Cronbach's α, a measure of reliability, per domain ranged from 0.73 to 0.93 in both cohorts with no significant difference documenting the reliability over time. Beside rigorous content and face validity, the congruent validity of the instrument showed adequate correlation with four gold standard questions measuring overall satisfaction. The non-differential validity was confirmed with no significant differences between the population characteristics and the domains, except that parents with a child for a surgical admission were more satisfied on information issues. CONCLUSIONS: The final EMPATHIC questionnaire incorporates 65 statements. The empirical structure of the satisfaction statements and domains was satisfactory. The reliability and validity proved to be adequate. The EMPATHIC questionnaire is a valid quality performance indicator to measure quality of care as perceived by parents