Quality of life and near vision impairment due to functional presbyopia among rural Chinese adults.

PURPOSE: To evaluate the impact of near-vision impairment on visual functioning and quality of life in a rural adult population in Shenyang, northern China. METHODS: A population-based, cross-sectional study was conducted among persons aged 40+ years, during which functional presbyopia (correctable presenting near vision < 20/50 [N8] at 40 cm) was assessed. Near-vision-related quality of life and spectacle usage questionnaires were administered by trained interviewers to determine the degree of self-rated difficulty with near tasks. RESULTS: A total of 1008 respondents (91.5% of 1102 eligible persons) were examined, and 776 (78%) of completed the questionnaires (mean age, 57.0 ± 10.2 years; 63.3% women). Near-vision spectacle wearers obtained their spectacles primarily from markets (74.5%) and optical shops (21.7%), and only 1.14% from eye clinics. Among 538 (69.3%) persons with functional presbyopia, self-rated overall (distance and near) vision was worse (P < 0.001) and difficulty with activities of daily living greater (P < 0.001) than among nonpresbyopes. Odds of reporting any difficulty with daily tasks remained higher (OR = 2.32; P < 0.001) for presbyopes after adjustment for age, sex, education and distance vision. Compared to persons without presbyopia, presbyopic persons were more likely to report diminished accomplishment due to vision (P = 0.01, adjusted for age, sex, education, and distance vision.) CONCLUSIONS: Difficulties with activities of daily living and resulting social impediments are common due to presbyopia in this setting. Most spectacle wearers with presbyopia in rural China obtain near correction from sources that do not provide comprehensive vision care.

Healthcare Staff Experience of Providing End-of-Life Care to Children: A Mixed Method Review

Background: Staff who provide end-of-life care to children not only have to deal with their own sense of loss, but also that of bereaved families. There is a dearth of knowledge on how they cope with these challenges.
Aim: The aim of this review is to explore the experiences of health care professionals who provide end-of-life care to children in order to inform the development of interventions to support them, thereby improving the quality of paediatric care for both children and their families.
Data sources: Searches included CINAHL, MEDLINE, Web of Science, EMBASE, PsychINFO, and The Cochrane Library in June 2015, with no date restrictions. Additional literature was uncovered from searching reference lists of relevant studies, along with contacting experts in the field of paediatric palliative care.
Design: This was a systematic mixed studies review. Study selection, appraisal and data extraction were conducted by two independent researchers. Integrative thematic analysis was used to synthesise the data.
Results: The 16 qualitative, six quantitative, and eight mixed-method studies identified included healthcare professionals in a range of settings. Key themes identified rewards and challenges of providing end-of-life care to children, the impact on staff’s personal and professional lives, coping strategies, and key approaches to help support staff in their role.
Conclusions: Education focusing on the unique challenges of providing end-of-life care to children and the importance of self-care, along with timely multidisciplinary debriefing are key strategies for improving healthcare staffs’ experiences, and as such the quality of care they provide.

Eliciting Security Requirements and Tracing them to Design: An Integration of Common Criteria, Heuristics, and UMLsec

Building secure systems is difficult for many reasons. This paper deals with two of the main challenges: (i) the lack of security expertise in development teams, and (ii) the inadequacy of existing methodologies to support developers who are not security experts. The security standard ISO 14508 (Common Criteria) together with secure design techniques such as UMLsec can provide the security expertise, knowledge, and guidelines that are needed. However, security expertise and guidelines are not stated explicitly in the Common Criteria. They are rather phrased in security domain terminology and difficult to understand for developers. This means that some general security and secure design expertise are required to fully take advantage of the Common Criteria and UMLsec. In addition, there is the problem of tracing security requirements and objectives into solution design,which is needed for proof of requirements fulfilment. This paper describes a security requirements engineering methodology called SecReq. SecReq combines three techniques: the Common Criteria, the heuristic requirements editorHeRA, andUMLsec. SecReqmakes systematic use of the security engineering knowledge contained in the Common Criteria and UMLsec, as well as security-related heuristics in the HeRA tool. The integrated SecReq method supports early detection of security-related issues (HeRA), their systematic refinement guided by the Common Criteria, and the ability to trace security requirements into UML design models. A feedback loop helps reusing experiencewithin SecReq and turns the approach into an iterative process for the secure system life-cycle, also in the presence of system evolution.

Curriculum and beyond: Mathematics support for first year life science students

The move into higher education is a real challenge for students from all educational backgrounds, with the adaptation to a new curriculum and style of learning and teaching posing a daunting task. A series of exercises were planned to boost the impact of the mathematics support for level four students and was focussed around a core module for all students. The intention was to develop greater confidence in tackling mathematical problems in all levels of ability and to provide more structured transition period in the first semester of level 4. Over a two-year period the teaching team for Biochemistry and Molecular Biology provided a series of structured formative tutorials and “interactive” online problems. Video solutions to all formative problems were made available, in order that students were able to engage with the problems at any time and were not disadvantaged if they could not attend. The formative problems were specifically set to dovetail into a practical report in which the mathematical skills developed were specifically assessed. Students overwhelmingly agreed that the structured formative activities had broadened their understanding of the subject and that more such activities would help. Furthermore, it is interesting to note that the package of changes undertaken resulted in a significant increase in the overall module mark over the two years of development.

Impact of a price-maker pumped storage hydro unit on the integration of wind energy in power systems

The increasing integration of larger amounts of wind energy into power systems raises important operational issues, such as the balance between power generation and demand. The pumped storage hydro (PSH) units are one possible solution to mitigate this problem, once they can store the excess of energy in the periods of higher generation and lower demand. However, the behaviour of a PSH unit may differ considerably from the expected in terms of wind power integration when it operates in a liberalized electricity market under a price-maker context. In this regard, this paper models and computes the optimal PSH weekly scheduling in a price-taker and price-maker scenarios, either when the PSH unit operates in standalone and integrated in a portfolio of other generation assets. Results show that the price-maker standalone PSH will integrate less wind power in comparison with the price-taker situation. Moreover, when the PSH unit is integrated in a portfolio with a base load power plant, the role of the price elasticity of demand may completely change the operational profile of the PSH unit. (C) 2014 Elsevier Ltd. All rights reserved.

Theory and numerical integration of subsurface light transport

En synthèse d’images, reproduire les effets complexes de la lumière sur des matériaux transluminescents, tels que la cire, le marbre ou la peau, contribue grandement au réalisme d’une image. Malheureusement, ce réalisme supplémentaire est couteux en temps de calcul. Les modèles basés sur la théorie de la diffusion visent à réduire ce coût en simulant le comportement physique du transport de la lumière sous surfacique tout en imposant des contraintes de variation sur la lumière incidente et sortante. Une composante importante de ces modèles est leur application à évaluer hiérarchiquement l’intégrale numérique de l’illumination sur la surface d’un objet. Cette thèse révise en premier lieu la littérature actuelle sur la simulation réaliste de la transluminescence, avant d’investiguer plus en profondeur leur application et les extensions des modèles de diffusion en synthèse d’images. Ainsi, nous proposons et évaluons une nouvelle technique d’intégration numérique hiérarchique utilisant une nouvelle analyse fréquentielle de la lumière sortante et incidente pour adapter efficacement le taux d’échantillonnage pendant l’intégration. Nous appliquons cette théorie à plusieurs modèles qui correspondent à l’état de l’art en diffusion, octroyant une amélioration possible à leur efficacité et précision.

Characterizations of Life Distributions Using Conditional Expectations of Doubly (Interval) Truncated Random Variables

In this article, we study reliability measures such as geometric vitality function and conditional Shannon’s measures of uncertainty proposed by Ebrahimi (1996) and Sankaran and Gupta (1999), respectively, for the doubly (interval) truncated random variables. In survival analysis and reliability engineering, these measures play a significant role in studying the various characteristics of a system/component when it fails between two time points. The interrelationships among these uncertainty measures for various distributions are derived and proved characterization theorems arising out of them

Compositions in life science data

The aim of this talk is to convince the reader that there are a lot of interesting statistical problems in presentday life science data analysis which seem ultimately connected with compositional statistics. Key words: SAGE, cDNA microarrays, (1D-)NMR, virus quasispecies

Integration of chaos theory and mathematical models in building simulation: Part I: Literature review

Current mathematical models in building research have been limited in most studies to linear dynamics systems. A literature review of past studies investigating chaos theory approaches in building simulation models suggests that as a basis chaos model is valid and can handle the increasingly complexity of building systems that have dynamic interactions among all the distributed and hierarchical systems on the one hand, and the environment and occupants on the other. The review also identifies the paucity of literature and the need for a suitable methodology of linking chaos theory to mathematical models in building design and management studies. This study is broadly divided into two parts and presented in two companion papers. Part (I) reviews the current state of the chaos theory models as a starting point for establishing theories that can be effectively applied to building simulation models. Part (II) develops conceptual frameworks that approach current model methodologies from the theoretical perspective provided by chaos theory, with a focus on the key concepts and their potential to help to better understand the nonlinear dynamic nature of built environment systems. Case studies are also presented which demonstrate the potential usefulness of chaos theory driven models in a wide variety of leading areas of building research. This study distills the fundamental properties and the most relevant characteristics of chaos theory essential to building simulation scientists, initiates a dialogue and builds bridges between scientists and engineers, and stimulates future research about a wide range of issues on building environmental systems.

Attribution of extreme weather events in Africa: A preliminary exploration of the science and policy implications

At the most recent session of the Conference of the Parties (COP19) in Warsaw (November 2013) the Warsaw international mechanism for loss and damage associated with climate change impacts was established under the United Nations Framework Convention on Climate Change (UNFCCC). The mechanism aims at promoting the implementation of approaches to address loss and damage associated with the adverse effects of climate change. Specifically, it aims to enhance understanding of risk management approaches to address loss and damage. Understanding risks associated with impacts due to highly predictable (slow onset) events like sea-level rise is relatively straightforward whereas assessing the effects of climate change on extreme weather events and their impacts is much more difficult. However, extreme weather events are a significant cause of loss of life and livelihoods, particularly in vulnerable countries and communities in Africa. The emerging science of probabilistic event attribution is relevant as it provides scientific evidence on the contribution of anthropogenic climate change to changes in risk of extreme events. It thus provides the opportunity to explore scientifically-backed assessments of the human influence on such events. However, different ways of framing attribution questions can lead to very different assessments of change in risk. Here we explain the methods of, and implications of different approaches to attributing extreme weather events with a focus on Africa. Crucially, it demonstrates that defining the most appropriate attribution question to ask is not a science decision but needs to be made in dialogue with those stakeholders who will use the answers.

A longitudinal study of coping strategies and quality of life among people with multiple sclerosis

The current study was designed to examine the role of coping strategies on quality of life (QOL) of people with multiple sclerosis (MS) over a period of 12 months. Respondents were 321 people with MS and 239 people from the general population who completed measures of QOL on two occasions, 12 months apart. People with MS also completed measures of how they coped with their illness. The results demonstrated that people with MS experienced lower levels of QOL at both points in time. For people with MS, QOL domains strongly predicted other QOL domains at both time 1 and time 2. The coping strategies of social support, focusing on the positive and wishful thinking were consistent predictors of physical QOL, psychological QOL, social QOL and environmental QOL. These findings indicate that coping strategies play an important role in predicting the QOL of people with MS.
Keywords Coping - Multiple sclerosis - Quality

Parent-proxy and child self-reported health-related quality of life: using qualitative methods to explain the discordance

Background: Although parent-proxy reports of health-related quality of life (HRQOL) are only moderately correlated with child reported HRQOL, it remains unknown why these scores differ. The aim of this study was to use a qualitative methodology to examine why parents and children report different levels of HRQOL.

Method: The sample consisted of 15 parent–child pairs. A think-aloud technique was used where parents and children were given a generic HRQOL instrument (KIDSCREEN) and instructed to share their thoughts with the interviewer. Qualitative analyses were conducted to assess whether parents and children base their answer on different experiences or reasoning, have different response styles, or interpret the items differently.

Results: There was discordance between parents and children, in terms of rating scale and in terms of the reasoning for their answer. Children tended to have different response styles to parents, where for example, children tended to provide extreme scores (highest or lowest score) and base their response on one single example, more than parents. Parents and children interpreted the meaning of the items very similarly.

Discussion: This study provides evidence to suggest that discordance among parent-child pairs on KIDSCREEN scores may be as a result of different reasoning and different response styles, rather than interpretation of items. These findings have important implications when parent-proxy reported HRQOL is used to guide clinical/treatment decisions.