The Influence of Silicon Nanoclusters on the Optical Properties of a-SiNx Samples: A Theoretical Study

By means of ab-initio calculations we investigate the optical properties of pure a-SiN$_x$ samples, with $x \in [0.4, 1.8]$, and samples embedding silicon nanoclusters (NCs) of diameter $0.5 \leq d \leq 1.0$ nm. In the pure samples the optical absorption gap and the radiative recombination rate vary according to the concentration of Si-N bonds. In the presence of NCs the radiative rate of the samples is barely affected, indicating that the intense photoluminescence of experimental samples is mostly due to the matrix itself rather than to the NCs. Besides, we evidence an important role of Si-N-Si bonds at the NC/matrix interface in the observed photoluminescence trend

Helping carers to care: the 10/66 dementia research group's randomized control trial of a caregiver intervention in Peru

OBJECTIVE There is a need, in the absence of formal services, to design interventions aimed at improving the lives of people with dementia and their families. This study tested the effectiveness of the 10/66 caregiver intervention among people with dementia and their caregivers in Lima, Peru. METHOD Design/participants: a randomized controlled trial was performed involving 58 caregivers of people with dementia that received the intervention in the beginning of the trial (n = 29) or six months later (n = 29). The intervention consisted of three modules: 1) assessment (one session); 2) basic education about dementia (two sessions); and 3) training regarding specific problem behaviors (two sessions). Main outcome measures: Caregivers and patients with dementia were assessed at baseline and after six months. For caregivers, the measures included strain (Zarit Burden Interview), psychological distress (SRQ-20), and quality of life (WHOQOL-BREF). Dementia patients completed scales assessing behavioral and psychological symptoms (NPI-Q) and quality of life (DEMQOL). RESULTS Caregivers in the intervention group reported significantly decreased strain measures six months after the intervention compared to controls. No group differences were found in respect to the caregivers' psychological distress and to quality of life in both caregivers and patients. CONCLUSION The 10/66 intervention seems to be as effective as similar interventions used in more developed countries

Psychometric properties of EURO-D, a geriatric depression scale: a cross-cultural validation study

Background: Many of the assessment tools used to study depression among older people are adaptations of instruments developed in other cultural setting. There is a need to validate those instruments in low and middle income countries (LMIC).Methods: A one-phase cross-sectional survey of people aged [greater than or equal to] 65 years from LMIC. EURO-D was checked for psychometric properties. Calibration with clinical diagnosis was made using ICD-10. Optimal cutpoint was determined. Concurrent validity was assessed measuring correlations with WHODAS 2.0.Results: 17,852 interviews were completed in 13 sites from nine countries. EURO-D constituted a hierarchical scale in most sites. the most commonly endorsed symptom in Latin American sites was depression; in China was sleep disturbance and tearfulness; in India, irritability and fatigue and in Nigeria loss of enjoyment. Two factor structure (affective and motivation) were demonstrated. Measurement invariance was demonstrated among Latin American and Indian sites being less evident in China and Nigeria. At the 4/5 cutpoint, sensitivity for ICD-10 depressive episode was 86% or higher in all sites and specificity exceeded 84% in all Latin America and Chinese sites. Concurrent validity was supported, at least for Latin American and Indian sites.Conclusions: There is evidence for the cross-cultural validity of the EURO-D scale at Latin American and Indian settings and its potential applicability in comparative epidemiological studies.Wellcome Trust (UK)WHOUS Alzheimer's AssociationFONACIT-VenezuelaPuerto Rico State LegislatureInst Memory Depress & Dis Risk, Lima 12, PeruKings Coll London, Ctr Global Mental Hlth, Hlth Serv & Populat Res Dept, Inst Psychiat Psychol & Neurosci, London WC2R 2LS, EnglandPeruvian Univ, Lima, PeruUniversidade Federal de São Paulo, UNIFESP, São Paulo, BrazilMed Univ Havana, Havana, CubaUniversidade Federal de São Paulo, UNIFESP, São Paulo, BrazilWellcome Trust (UK): GR066133US Alzheimer's Association: IIRG-04-1286Web of Scienc

The economic status of older people’s households in urban and rural settings in Peru, Mexico and China: a 10/66 INDEP study cross-sectional survey

Few data are available from middle income countries regarding economic circumstances of households in which older people live. Many such settings have experienced rapid demographic, social and economic change, alongside increasing pension coverage. Population-based household surveys in rural and urban catchment areas in Peru, Mexico and China. Participating households were selected from all households with older residents. Descriptive analyses were weighted back for sampling fractions and non-response. Household income and consumption were estimated from a household key informant interview. 877 Household interviews (3177 residents). Response rate 68 %. Household income and consumption correlated plausibly with other economic wellbeing indicators. Household Incomes varied considerably within and between sites. While multigenerational households were the norm, older resident’s incomes accounted for a high proportion of household income, and older people were particularly likely to pool income. Differences in the coverage and value of pensions were a major source of variation in household income among sites. There was a small, consistent inverse association between household pension income and labour force participation of younger adult co-residents. The effect of pension income on older adults’ labour force participation was less clear-cut. Historical linkage of social protection to formal employment may have contributed to profound late-life socioeconomic inequalities. Strategies to formalise the informal economy, alongside increases in the coverage and value of non-contributory pensions and transfers would help to address this problem

A cohort study of the effects of older adult care dependence upon household economic functioning, in Peru, Mexico and China

BACKGROUND: While links between disability and poverty are well established, there have been few longitudinal studies to clarify direction of causality, particularly among older adults in low and middle income countries. We aimed to study the effect of care dependence among older adult residents on the economic functioning of their households, in catchment area survey sites in Peru, Mexico and China. METHODS: Households were classified from the evolution of the needs for care of older residents, over two previous community surveys, as 'incident care', 'chronic care' or 'no care', and followed up three years later to ascertain economic outcomes (household income, consumption, economic strain, satisfaction with economic circumstances, healthcare expenditure and residents giving up work or education to care). RESULTS: Household income did not differ between household groups. However, income from paid work (Pooled Count Ratio pCR 0.88, 95% CI 0.78-1.00) and government transfers (pCR 0.80, 95% CI 0.69-0.93) were lower in care households. Consumption was 12% lower in chronic care households (pCR 0.88, 95% CI 0.77-0.99). Household healthcare expenditure was higher (pCR 1.55, 95% CI 1.26-1.90), and catastrophic healthcare spending more common (pRR 1.64, 95% CI 1.64-2.22) in care households. CONCLUSIONS: While endogeneity cannot be confidently excluded as an explanation for the findings, this study indicates that older people's needs for care have a discernable impact on household economics, controlling for baseline indicators of long-term economic status. Although living, typically, in multigenerational family units, older people have not featured prominently in global health and development agendas. Population ageing will rapidly increase the number of households where older people live, and their societal significance. Building sustainable long-term care systems for the future will require some combination of improved income security in old age; incentivisation of informal care through compensation for direct and opportunity costs; and development of community care services to support, and, where necessary, supplement or substitute the central role of informal caregivers

Socioeconomic Factors and All Cause and Cause-Specific Mortality among Older People in Latin America, India, and China: A Population-Based Cohort Study

Cleusa Ferri and colleagues studied mortality rates in over 12,000 people aged 65 years and over in Latin America, India, and China and showed that chronic diseases are the main causes of death and that education has an important effect on mortality

Prevalence of stroke and related burden among older people living in Latin America, India and China

Objectives Despite the growing importance of stroke in developing countries, little is known of stroke burden in survivors. the authors investigated the prevalence of self-reported stroke, stroke-related disability, dependence and care-giver strain in Latin America (LA), China and India.Methods Cross-sectional surveys were conducted on individuals aged 65+ (n=15 022) living in specified catchment areas. Self-reported stroke diagnosis, disability, care needs and care giver burden were assessed using a standardised protocol. for those reporting stroke, the correlates of disability, dependence and care-giver burden were estimated at each site using Poisson or linear regression, and combined meta-analytically.Results the prevalence of self-reported stroke ranged between 6% and 9% across most LA sites and urban China, but was much lower in urban India (1.9%), and in rural sites in India (1.1%), China (1.6%) and Peru (2.7%). the proportion of stroke survivors needing care varied between 20% and 39% in LA sites but was higher in rural China (44%), urban China (54%) and rural India (73%). Comorbid dementia and depression were the main correlates of disability and dependence.Conclusion the prevalence of stroke in urban LA and Chinese sites is nearly as high as in industrialised countries. High levels of disability and dependence in the other mainly rural and less-developed sites suggest underascertainment of less severe cases as one likely explanation for the lower prevalence in those settings. As the health transition proceeds, a further increase in numbers of older stroke survivors is to be anticipated. in addition to prevention, stroke rehabilitation and long-term care needs should be addressed.Wellcome TrustWorld Health Organization (India, Dominican Republic and China)US Alzheimer's AssociationFONACIT/ CDCH/ UCV (Venezuela)Kings Coll London, Inst Psychiat, Epidemiol Sect, Hlth Serv, London SE5 8AF, EnglandKings Coll London, Inst Psychiat, Clin Neurosci Div, London SE5 8AF, EnglandUniv Nacl Pedro Henriquez Urena, Geriatr Sect, Santo Domingo, Dominican RepUniv Peruana Cayetano Heredia, Lima, PeruPeking Univ, Inst Mental Hlth, Div Social Psychiat & Behav Med, Beijing 100871, Peoples R ChinaChristian Med Coll & Hosp, Vellore, Tamil Nadu, IndiaMed Univ Havana, Dept Clin Sci, Havana, CubaCaracas Univ Hosp, Dept Med, Caracas, VenezuelaNatl Inst Neurol & Neurosurg Mexico, Mexico City, DF, MexicoVHS, Dept Community Hlth, Chennai, Tamil Nadu, IndiaUniversidade Federal de São Paulo, Dept Psychiat, São Paulo, BrazilUniv Ciencias Med Matanzas, Dept Internal Med, Matanzas, CubaKings Coll London, Inst Psychiat, Epidemiol Sect, Populat Res Dept, London SE5 8AF, EnglandUniversidade Federal de São Paulo, Dept Psychiat, São Paulo, BrazilWellcome Trust: GR066133Wellcome Trust: GR08002US Alzheimer's Association: IIRG-04-1286Web of Scienc

Dietary fish and meat intake and dementia in Latin America, China, and India: a 10/66 Dementia Research Group population-based study123

Background: Evidence of an association between fish and meat consumption and risk of dementia is inconsistent and nonexistent in populations in developing countries

A journey without maps—Understanding the costs of caring for dependent older people in Nigeria, China, Mexico and Peru

Purpose of the study: Populations in Latin America, Asia and sub-Saharan Africa are rapidly ageing. The extent to which traditional systems of family support and security can manage the care of increased numbers of older people with chronic health problems is unclear. Our aim was to explore the social and economic effects of caring for an older dependent person, including insight into pathways to economic vulnerability. Design & methods: We carried out a series of household case studies across urban and rural sites in Peru, Mexico, China and Nigeria (n = 24), as part of a cross-sectional study, nested within the 10/66 Dementia Research Group cohort. Case studies consisted of in-depth narrative style interviews (n = 60) with multiple family members, including the older dependent person. Results: Governments were largely uninvolved in the care and support of older dependent people, leaving families to negotiate a ‘journey without maps’. Women were de facto caregivers but the traditional role of female relative as caregiver was beginning to be contested. Household composition was flexible and responsive to changing needs of multiple generations but family finances were stretched. Implications: Governments are lagging behind sociodemographic and social change. There is an urgent need for policy frameworks to support and supplement inputs from families. These should include community-based and residential care services, disability benefits and carers allowances. Further enhancement of health insurance schemes and scale-up of social pensions are an important component of bolstering the security of dependent older people and supporting their continued social and economic participation