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Longitudinal data resource from the Wellbeing of Older People cohort of people aged >50 years in Uganda and South Africa from 2009 to 2019. S Afr Med J 2023; 113:36-41. [PMID: 37882122 DOI: 10.7196/samj.2023.v113i8.16706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND The population of people aged ≥60 years continues to increase globally, and has been projected by the United Nations Population Division to increase to 21% of the total population by 2050. In addition, the number of older people living with HIV has continued to increase owing to the introduction of antiretroviral therapy as a treatment for HIV-infected people. Most of the older people living with HIV are in sub-Saharan Africa, an area that faces the biggest burden of HIV globally. Despite the high burden, there are limited reliable data on how HIV directly and indirectly affects the health and wellbeing of older people within this region. OBJECTIVE To showcase the availability of data on how HIV directly and indirectly affects the health and wellbeing of older people in Uganda and South Africa (SA). METHODS The World Health Organization Study on global AGEing and adult health (SAGE), in collaboration with Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine (MRC/UVRI and LSHTM) Uganda Research Unit and the Africa Health Research Institute (AHRI) in SA, started the SAGE Wellbeing of Older People Study (WOPS) in Uganda and SA in 2009. Since initiation, respondents have been surveyed every 2 years, with four waves of surveys conducted in Uganda and three waves in South Africa. RESULTS The available datasets consist of two cohorts of people, aged >50 years, who were surveyed every 2 years between 2009 and 2018. The prevalence of HIV positivity over this period increased from 39% to 54% in Uganda and 48% to 62% in SA. The datasets provide comparisons of variables at a household level and at an individual level. At the individual level, the following measures can be compared longitudinally for a 10-year period for the following variables: sociodemographic characteristics; work history and benefits; health states and descriptions; anthropometrics performance tests and biomarkers; risk factors and preventive health behaviours; chronic conditions and health services coverage; healthcare utilisation; social cohesion; subjective wellbeing and quality of life; and impact of caregiving. CONCLUSION This article describes the WOPS in Uganda and SA, the population coverage of this study, and the survey frequency of WOPS, survey measures, data resources available, the data resource access and the strengths and weaknesses of the study. The article invites interested researchers to further analyse the data and answer research questions of interest to enhance the impact of these data.
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Epithelial Cell-Like Elasticity Modulates Actin-Dependent E-Cadherin Adhesion Organization. ACS Biomater Sci Eng 2022; 8:2455-2462. [PMID: 35549026 PMCID: PMC9199519 DOI: 10.1021/acsbiomaterials.2c00253] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
E-cadherin adhesions are essential for cell-to-cell cohesion and mechanical coupling between epithelial cells and reside in a microenvironment that comprises the adjoining epithelial cells. While E-cadherin has been shown to be a mechanosensor, it is unknown if E-cadherin adhesions can differentially sense stiffness within the range of that of epithelial cells. A survey of literature shows that epithelial cells' Young's moduli of elasticity lie predominantly in the sub-kPa to few-kPa range, with cancer cells often being softer than noncancerous ones. Here, we devised oriented E-cadherin-coated soft silicone substrates with sub-kPa or few-kPa elasticity but with similar viscous moduli and found that E-cadherin adhesions differentially organize depending on the magnitude of epithelial cell-like elasticity. Our results show that the actin cytoskeleton organizes E-cadherin adhesions in two ways─by supporting irregularly shaped adhesions at localized regions of high actin density and linear shaped adhesions at the end of linear actin bundles. Linearly shaped E-cadherin adhesions associated with radially oriented actin─but not irregularly shaped E-cadherin adhesions associated with circumferential actin foci─were much more numerous on 2.4 kPa E-cadherin substrates compared to 0.3 kPa E-cadherin substrates. However, the total amount of E-cadherin in both types of adhesions taken together was similar on the 0.3 and 2.4 kPa E-cadherin substrates across many cells. Our results show how the distribution of E-cadherin adhesions, supported by actin density and architecture, is modulated by epithelial cell-like elasticity and have significant implications for disease states like carcinomas characterized by altered epithelial cell elasticity.
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Abstract
Aims:We aimed to explore the expert perspective on relevant issues of individuals with bipolar disorder. The specific aims are to identify problems in functioning important to individuals with BD and to quantify these using the ICF.Method:An online survey on functioning in BD was conduced. For each ICF domain one question was presented. Recruited participants were psychiatrists, general physicians, psychologists, nurses and social workers worldwide. Answers were linked to the ICF according to predefined rules (Cieza, 2001). Data analyses include frequencies of ICF categories named by experts.Results:Health professionals from all WHO-world regions and from different professional backgrounds accepted our invitation to participate. The Americas was the highest represented region (36%) and a significant part of the professionals involved were psychiatrists. From all the concepts contained in the answers, body functions categories with highest frequency of appearance were emotional functions (3,5%), mentioned by 62% of the experts and sleep functions (2,4%) mentioned by 58%. The body structure brain corresponds to 2% of the total categories obtained and was included by 56% of the experts. Maintaining one's health was the most mentioned activity and participation (2,8%), referred by 36% of the participants and important environmental factors include health services (4,8%) and immediate family(3,8%), which appeared in 82% of the questionnaires.Conclusion:The present study is an important step in applying of the ICF to BD. It also shows an important level of agreement between experts around the world regarding central issues of the disorder.Funded by MURINET-MRTN-CT-2006-035794
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sEMG signal classification with novel feature extraction using different machine learning approaches. JOURNAL OF INTELLIGENT & FUZZY SYSTEMS 2018. [DOI: 10.3233/jifs-169794] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Stiffness Measurement of Soft Silicone Substrates for Mechanobiology Studies Using a Widefield Fluorescence Microscope. J Vis Exp 2018. [PMID: 30035766 DOI: 10.3791/57797] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Soft tissues in the human body typically have stiffness in the kilopascal (kPa) range. Accordingly, silicone and hydrogel flexible substrates have been proven to be useful substrates for culturing cells in a physical microenvironment that partially mimics in vivo conditions. Here, we present a simple protocol for characterizing the Young's moduli of isotropic linear elastic substrates typically used for mechanobiology studies. The protocol consists of preparing a soft silicone substrate on a Petri dish or stiff silicone, coating the top surface of the silicone substrate with fluorescent beads, using a millimeter-scale sphere to indent the top surface (by gravity), imaging the fluorescent beads on the indented silicone surface using a fluorescence microscope, and analyzing the resultant images to calculate the Young's modulus of the silicone substrate. Coupling the substrate's top surface with a moduli extracellular matrix protein (in addition to the fluorescent beads) allows the silicone substrate to be readily used for cell plating and subsequent studies using traction force microscopy experiments. The use of stiff silicone, instead of a Petri dish, as the base of the soft silicone, enables the use of mechanobiology studies involving external stretch. A specific advantage of this protocol is that a widefield fluorescence microscope, which is commonly available in many labs, is the major equipment necessary for this procedure. We demonstrate this protocol by measuring the Young's modulus of soft silicone substrates of different elastic moduli.
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Socio-economic variations in the mental health treatment gap for people with anxiety, mood, and substance use disorders: results from the WHO World Mental Health (WMH) surveys. Psychol Med 2018; 48:1560-1571. [PMID: 29173244 PMCID: PMC6878971 DOI: 10.1017/s0033291717003336] [Citation(s) in RCA: 228] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The treatment gap between the number of people with mental disorders and the number treated represents a major public health challenge. We examine this gap by socio-economic status (SES; indicated by family income and respondent education) and service sector in a cross-national analysis of community epidemiological survey data. METHODS Data come from 16 753 respondents with 12-month DSM-IV disorders from community surveys in 25 countries in the WHO World Mental Health Survey Initiative. DSM-IV anxiety, mood, or substance disorders and treatment of these disorders were assessed with the WHO Composite International Diagnostic Interview (CIDI). RESULTS Only 13.7% of 12-month DSM-IV/CIDI cases in lower-middle-income countries, 22.0% in upper-middle-income countries, and 36.8% in high-income countries received treatment. Highest-SES respondents were somewhat more likely to receive treatment, but this was true mostly for specialty mental health treatment, where the association was positive with education (highest treatment among respondents with the highest education and a weak association of education with treatment among other respondents) but non-monotonic with income (somewhat lower treatment rates among middle-income respondents and equivalent among those with high and low incomes). CONCLUSIONS The modest, but nonetheless stronger, an association of education than income with treatment raises questions about a financial barriers interpretation of the inverse association of SES with treatment, although future within-country analyses that consider contextual factors might document other important specifications. While beyond the scope of this report, such an expanded analysis could have important implications for designing interventions aimed at increasing mental disorder treatment among socio-economically disadvantaged people.
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An IL-10 dominant polarization of monocytes is a feature of Indian Visceral Leishmaniasis. Parasite Immunol 2018; 40:e12535. [DOI: 10.1111/pim.12535] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 05/02/2018] [Indexed: 01/01/2023]
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Human Osteoblast-Derived Extracellular Matrix with High Homology to Bone Proteome Is Osteopromotive. Tissue Eng Part A 2018; 24:1377-1389. [PMID: 29667532 DOI: 10.1089/ten.tea.2017.0448] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Efficient osteogenic differentiation of mesenchymal stromal cells (MSCs) is crucial to accelerate bone formation. In this context, the use of extracellular matrix (ECM) as natural 3D framework mimicking in vivo tissue architecture is of interest. The aim of this study was to generate a devitalized human osteogenic MSC-derived ECM and to investigate its impact on MSC osteogenic differentiation to improve MSC properties in bone regeneration. The devitalized ECM significantly enhanced MSC adhesion and proliferation. Osteogenic differentiation and mineralization of MSCs on the ECM were quicker than in standard conditions. The presence of ECM promoted in vivo bone formation by MSCs in a mouse model of ectopic calcification. We analyzed the ECM composition by mass spectrometry, detecting 846 proteins. Of these, 473 proteins were shared with the human bone proteome we previously described, demonstrating high homology to an in vivo microenvironment. Bioinformatic analysis of the 846 proteins showed involvement in adhesion and osteogenic differentiation, confirming the ECM composition as key modulator of MSC behavior. In addition to known ECM components, proteomic analysis revealed novel ECM functions, which could improve culture conditions. In summary, this study provides a simplified method to obtain an in vitro MSC-derived ECM that enhances osteogenic differentiation and could be applied as natural biomaterial to accelerate bone regeneration.
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Treatment of stable slipped capital femoral epiphysis: systematic review and exploratory patient level analysis. J Orthop Traumatol 2017; 18:379-394. [PMID: 28831651 PMCID: PMC5685987 DOI: 10.1007/s10195-017-0469-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 07/13/2017] [Indexed: 01/29/2023] Open
Abstract
Background Several aspects of slipped capital femoral epiphysis (SCFE) treatment remain controversial. Loder’s work has been instrumental in changing our understanding and approach to the management of the condition when he introduced the concept of “slip instability” and showed that avascular necrosis (AVN) developed in 47% of unstable slips but none of the stable slips. As the two types of SCFE behave differently in terms of presentation, progress and complications, we approached them as two different conditions to highlight these differences. This paper focuses on treatments of stable SCFE. Materials and methods An extensive literature search was carried out from multiple databases. One thousand six hundred and twenty-three citations were screened. Three hundred and sixteen full publications were obtained for further scrutiny. Fifty-eight studies (2262 hips) were included in the review. These studies evaluated 6 interventions. AVN was chosen as a surrogate for bad outcome. Secondary outcomes were chondrolysis (CL), femoro-acetabular impingement (FAI), osteoarthritis (OA) and patients’ reported outcomes. The latter were pooled when they met our predefined criteria. Results The type of surgical intervention was an important risk factor. Pinning in situ (PIS) was associated with the lowest AVN rate (1.4%). Moreover, the CL, FAI and OA rates were relatively low in patients who underwent PIS. These were not translated into high patient satisfaction rates among these patients, with only 47% reporting an “excellent” outcome. In contrast, 87% of patients who underwent Ganz surgical dislocation reported an “excellent” outcome. The Ganz surgical dislocation was associated with an AVN rate of 3.3%; double that observed in pinning in situ. Conclusion Pinning in situ is the best treatment for mild and moderate stable slip. Ganz surgical dislocation gives higher patient satisfaction for severe stable slip but the risk of AVN is doubled compared with pinning in situ. Devices that allow continued growth may be better than standard screws. Level of evidence Level III.
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OVERVIEW OF THE ATHLOS PROJECT. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.4816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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DEVELOPING A SINGLE METRIC OF HEALTH USING MODERN DATA ANALYTICAL METHODS. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.4819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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POLICY AND KNOWLEDGE TRANSLATION IN THE ATHLOS PROJECT. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.4820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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GENDER-RELATED DIFFERENCES IN THE EFFECT OF SOCIAL DETERMINANTS ON QUALITY OF LIFE IN OLDER AGE. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.2956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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ALCOHOL CONSUMPTION IN OLDER ADULTS: RESULTS FROM SAGE, ELSA, HRS AND SHARE. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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IMPACT OF EDUCATION AND INCOME ON COGNITIVE FUNCTIONING IN LOW- AND MIDDLE-INCOME COUNTRIES. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.1501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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AGING AND HIV: A SUMMARY OF SAGE-WOPS HIV WAVES 1 AND 2 IN SOUTH AFRICA AND UGANDA. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.2186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Characterization of transient noise in Advanced LIGO relevant to gravitational wave signal GW150914. CLASSICAL AND QUANTUM GRAVITY 2016; 33:134001. [PMID: 32908328 PMCID: PMC7477940 DOI: 10.1088/0264-9381/33/13/134001] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
On September 14, 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal.
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Prevalence of and factors associated with frailty and disability in older adults from China, Ghana, India, Mexico, Russia and South Africa. Maturitas 2016; 91:8-18. [PMID: 27451316 DOI: 10.1016/j.maturitas.2016.05.012] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/18/2016] [Accepted: 05/23/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND The severe burden imposed by frailty and disability in old age is a major challenge for healthcare systems in low- and middle-income countries alike. The current study aimed to provide estimates of the prevalence of frailty and disability in older adult populations and to examine their relationship with socioeconomic factors in six countries. METHODS Focusing on adults aged 50+ years, a frailty index was constructed as the proportion of deficits in 40 variables, and disability was assessed using the World Health Organization Disability Assessment Schedule (WHODAS 2.0), as part of the Study on global AGEing and adult health (SAGE) Wave 1 in China, Ghana, India, Mexico, Russia and South Africa. RESULTS This study included a total of 34,123 respondents. China had the lowest percentages of older adults with frailty (13.1%) and with disability (69.6%), whereas India had the highest percentages (55.5% and 93.3%, respectively). Both frailty and disability increased with age for all countries, and were more frequent in women, although the sex gap varied across countries. Lower levels of both frailty and disability were observed at higher levels of education and wealth. Both education and income were protective factors for frailty and disability in China, India and Russia, whereas only income was protective in Mexico, and only education in South Africa. CONCLUSIONS Age-related frailty and disability are increasing concerns for older adult populations in low- and middle-income countries. The results indicate that lower levels of frailty and disability can be achieved for older people, and the study highlights the need for targeted preventive approaches and support programs.
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A case of spontaneous pneumothorax, pneumomediastinum & subcutaneous emphysema in Pneumocystis jirovecii pneumonia complicating HIV. SRI LANKAN JOURNAL OF INFECTIOUS DISEASES 2015; 5:22. [DOI: 10.4038/sljid.v5i1.7569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2023] Open
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Development of multi-grain capacitive sensor for determination of moisture content in grains. QUALITY ASSURANCE AND SAFETY OF CROPS & FOODS 2015. [DOI: 10.3920/qas2013.0285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Abstract
BACKGROUND Later years of life are accompanied by many physical, emotional and environmental changes which may impact on the well-being of the individual. Many factors are known to influence the subjective well-being of older adults, but most, if not all of this information was the result of studies in the Western world. This study aimed at obtaining and documenting the predictors of subjective well-being (SWB) among older Ghanaians. METHODS Data for the study was obtained from the WHO SAGE study. The single item measure of life satisfaction was used to determine subjective well-being. Descriptive statistics as well as logistic regression analysis were carried out to determine the predictors of SWB. RESULTS A total of 4724 individuals aged 50 years and above responded to the questionnaires. Of these 50.4% were males. Following multivariate logistic regression analysis, age, sex, educational level, income and ethnic background were found to significantly affect the SWB of older Ghanaians. Being male was associated with higher level of SWB (OR=1.68; CI: 1.39 - 2.03). For those 50 years and above, being younger (50-59 years) was also associated with a high level of SWB (OR=17.72; CI: 10.13-30.98). Earning a low income and having low educational level were both associated with low levels of SWB (OR=0.304; CI: 0.22-0.42; and OR=0.47; CI: 0.37-0.60 respectively). Ewes (p=0.027), Grumas (p=0.002) and Mole-Dagbons (p=0.04) had significantly higher SWB compared to the other ethnic groups. CONCLUSION Among older Ghanaians, factors that positively influence SWB are younger age, male sex, high educational level and high income.
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The Health and Functioning ICF-60: development and psychometric properties. Clin Psychol Psychother 2014; 21:437-51. [PMID: 24931300 PMCID: PMC4232882 DOI: 10.1002/cpp.1909] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 05/08/2014] [Accepted: 05/09/2014] [Indexed: 11/07/2022]
Abstract
Background This paper describes the development and psychometric properties of the Health and Functioning ICF-60 (HF-ICF-60) measure, based on the World Health Organization (WHO) ‘International Classification of Functioning, Disability and Health: ICF’ (2001). The aims of the present study were to test psychometric properties of the HF-ICF-60, developed as a measure that would be responsive to change in functioning through changes in health and nutritional status, as a prospective measure to monitor health and nutritional status of populations and to explore the relationship of the HF-ICF-60 with quality of life measures such as the World Health Organization WHOQOL-BREF quality of life assessment in relation to non-communicable diseases. Methods The HF-ICF-60 measure consists of 60 items selected from the ICF by an expert panel, which included 18 items that cover Body Functions, 21 items that cover Activities and Participation, rated on five-point scales, and 21 items that cover Environmental Factors (seven items cover Individual Environmental Factors and 14 items cover Societal Environmental Factors), rated on nine-point scales. The HF-ICF-60 measure was administered to the Russian nationally representative sample within the Russian National Population Quality of Life, Health and Nutrition Survey, in 2004 (n = 9807) and 2005 (n = 9560), as part of the two waves of the Russian Longitudinal Monitoring Survey (RLMS). The statistical analyses were carried out with the use of both classical and modern psychometric methods, such as factor analysis, and based on Item Response Theory, respectively. Results The HF-ICF-60 questionnaire is a new measure derived directly from the ICF and covers the ICF components as follows: Body Functions, Activities and Participation, and Environmental Factors (Individual Environmental Factors and Societal Environmental Factors). The results from the factor analyses (both Exploratory Factor Analyses and Confirmatory Factor Analyses) show good support for the proposed structure together with an overall higher-order factor for each scale of the measure. The measure has good reliability and validity, and sensitivity to change in the health and nutritional status of respondents over time. Normative values were developed for the Russian adult population. Conclusions The HF-ICF-60 has shown good psychometric properties in the two waves of the nationally representative RLMS, which provided considerable support to using the HF-ICF-60 data as the normative health and functioning values for the Russian population. Similarly, the administration of the WHOQOL-BREF in the same two waves of the nationally representative RLMS has allowed the normative quality of life values for the Russian population to be obtained. Therefore, the objective assessment of health and functioning of the HF-ICF-60 could be mapped onto the subjective evaluation of quality of life of the WHOQOL-BREF to increase the potential usefulness of the surveys in relation to non-communicable diseases. © 2014 The Authors. Clinical Psychology & Psychotherapy. Published by John Wiley & Sons, Ltd. Key Practitioner Message
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127 Identifying characteristics of patients diagnosed with lung cancer during emergency admission to hospital. Lung Cancer 2014. [DOI: 10.1016/s0169-5002(14)70128-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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S83 The use of indwelling pleural catheters (IPC) with or without concurrent talc poudrage (TP) at medical thoracoscopy (MT) for cases of suspected trapped lung (TL): Abstract S83 Table 1. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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P5 Impact of national lung cancer awareness campaign on local referrals and outcomes in non-small cell lung cancer (NSCLC): Abstract P5. Table 1. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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P50 A local assessment of the escalating impact of pulmonary nodule surveillance and its relationship to patient outcomes in a DGH. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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S81 A randomised controlled study comparing the outcomes of pleural nurse practitioner versus doctors trained to perform pleural procedures for management of pleural effusions. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.88] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Evidence for the early clinical relevance of hallucinatory-delusional states in the general population. Acta Psychiatr Scand 2013; 127:482-93. [PMID: 22943634 DOI: 10.1111/acps.12010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To analyze, in a general population sample, clustering of delusional and hallucinatory experiences in relation to environmental exposures and clinical parameters. METHOD General population-based household surveys of randomly selected adults between 18 and 65 years of age were carried out. SETTING 52 countries participating in the World Health Organization's World Health Survey were included. PARTICIPANTS 225 842 subjects (55.6% women), from nationally representative samples, with an individual response rate of 98.5% within households participated. RESULTS Compared with isolated delusions and hallucinations, co-occurrence of the two phenomena was associated with poorer outcome including worse general health and functioning status (OR = 0.93; 95% CI: 0.92-0.93), greater severity of symptoms (OR = 2.5 95% CI: 2.0-3.0), higher probability of lifetime diagnosis of psychotic disorder (OR = 12.9; 95% CI: 11.5-14.4), lifetime treatment for psychotic disorder (OR = 19.7; 95% CI: 17.3-22.5), and depression during the last 12 months (OR = 11.6; 95% CI: 10.9-12.4). Co-occurrence was also associated with adversity and hearing problems (OR = 2.0; 95% CI: 1.8-2.3). CONCLUSION The results suggest that the co-occurrence of hallucinations and delusions in populations is not random but instead can be seen, compared with either phenomenon in isolation, as the result of more etiologic loading leading to a more severe clinical state.
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Cross-national differences in the prevalence and correlates of burden among older family caregivers in the World Health Organization World Mental Health (WMH) Surveys. Psychol Med 2013; 43:865-879. [PMID: 22877824 PMCID: PMC4045502 DOI: 10.1017/s0033291712001468] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Current trends in population aging affect both recipients and providers of informal family caregiving, as the pool of family caregivers is shrinking while demand is increasing. Epidemiological research has not yet examined the implications of these trends for burdens experienced by aging family caregivers. Method Cross-sectional community surveys in 20 countries asked 13 892 respondents aged 50+ years about the objective (time, financial) and subjective (distress, embarrassment) burdens they experience in providing care to first-degree relatives with 12 broadly defined serious physical and mental conditions. Differential burden was examined by country income category, kinship status and type of condition. RESULTS Among the 26.9-42.5% respondents in high-, upper-middle-, and low-/lower-middle-income countries reporting serious relative health conditions, 35.7-42.5% reported burden. Of those, 25.2-29.0% spent time and 13.5-19.4% money, while 24.4-30.6% felt distress and 6.4-21.7% embarrassment. Mean caregiving hours per week in those giving any time were 16.6-23.6 (169.9-205.8 h/week per 100 people aged 50+ years). Burden in low-/lower-middle-income countries was 2- to 3-fold higher than in higher-income countries, with any financial burden averaging 14.3% of median family income in high-, 17.7% in upper-middle-, and 39.8% in low-/lower-middle-income countries. Higher burden was reported by women than men and for conditions of spouses and children than parents or siblings. CONCLUSIONS Uncompensated family caregiving is an important societal asset that offsets rising formal healthcare costs. However, the substantial burdens experienced by aging caregivers across multiple family health conditions and geographic regions threaten the continued integrity of their caregiving capacity. Initiatives supporting older family caregivers are consequently needed, especially in low-/lower-middle-income countries.
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196 An observational study of the use of indwelling pleural catheters for malignant pleural effusions – The Cambridge Pleural Unit experience. Lung Cancer 2013. [DOI: 10.1016/s0169-5002(13)70196-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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P123 The Use of Indwelling Pleural Catheters For the Management of Non-Malignant Recurrent Pleural Effusions: Abstract P123 Table 1. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Publisher’s Note: Search for gravitational waves associated with the August 2006 timing glitch of the Vela pulsar [Phys. Rev. D83, 042001 (2011)]. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.089902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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34
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Computer aided diagnostic tool for osteoporosis estimation. INTERNATIONAL JOURNAL OF BIOMEDICAL ENGINEERING AND TECHNOLOGY 2012. [DOI: 10.1504/ijbet.2012.049216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Days out of role because of health problems are a major source of lost human capital. We examined the relative importance of commonly occurring physical and mental disorders in accounting for days out of role in 24 countries that participated in the World Health Organization (WHO) World Mental Health (WMH) surveys. Face-to-face interviews were carried out with 62 971 respondents (72.0% pooled response rate). Presence of ten chronic physical disorders and nine mental disorders was assessed for each respondent along with information about the number of days in the past month each respondent reported being totally unable to work or carry out their other normal daily activities because of problems with either physical or mental health. Multiple regression analysis was used to estimate associations of specific conditions and comorbidities with days out of role, controlling by basic socio-demographics (age, gender, employment status and country). Overall, 12.8% of respondents had some day totally out of role, with a median of 51.1 a year. The strongest individual-level effects (days out of role per year) were associated with neurological disorders (17.4), bipolar disorder (17.3) and post-traumatic stress disorder (15.2). The strongest population-level effect was associated with pain conditions, which accounted for 21.5% of all days out of role (population attributable risk proportion). The 19 conditions accounted for 62.2% of all days out of role. Common health conditions, including mental disorders, make up a large proportion of the number of days out of role across a wide range of countries and should be addressed to substantially increase overall productivity.
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62 Does GP clinical history influence radiologists' interpretation of chest radiographs or reliably predict eventual diagnosis of lung malignancy? Lung Cancer 2011. [DOI: 10.1016/s0169-5002(11)70062-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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89 Repeat local validation of the National Lung Cancer Database (LUCADA) in 2006 and 2009 - how do they compare? Lung Cancer 2011. [DOI: 10.1016/s0169-5002(11)70089-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009; 102:111102. [PMID: 19392186 DOI: 10.1103/physrevlett.102.111102] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.80.042003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.79.022001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.77.022001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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648: A Review of Malignancies Developing Post Lung Transplantation and the Effect on Survival. J Heart Lung Transplant 2009. [DOI: 10.1016/j.healun.2008.11.655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Search for gravitational-wave bursts from soft gamma repeaters. PHYSICAL REVIEW LETTERS 2008; 101:211102. [PMID: 19113401 DOI: 10.1103/physrevlett.101.211102] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Indexed: 05/11/2023]
Abstract
We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.
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In-vacuum optical isolation changes by heating in a Faraday isolator. APPLIED OPTICS 2008; 47:5853-5861. [PMID: 19122727 DOI: 10.1364/ao.47.005853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe a model evaluating changes in the optical isolation of a Faraday isolator when passing from air to vacuum in terms of different thermal effects in the crystal. The changes are particularly significant in the crystal thermal lensing (refraction index and thermal expansion) and in its Verdet constant and can be ascribed to the less efficient convection cooling of the magneto-optic crystal of the Faraday isolator. An isolation decrease by a factor of 10 is experimentally observed in a Faraday isolator that is used in a gravitational wave experiment (Virgo) with a 10 W input laser when going from air to vacuum. A finite element model simulation reproduces with a great accuracy the experimental data measured on Virgo and on a test bench. A first set of measurements of the thermal lensing has been used to characterize the losses of the crystal, which depend on the sample. The isolation factor measured on Virgo confirms the simulation model and the absorption losses of 0.0016 +/- 0.0002/cm for the TGG magneto-optic crystal used in the Faraday isolator.
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The ICF as a Conceptual Platform to Specify and Discuss Health and Health-Related Concepts. DAS GESUNDHEITSWESEN 2008; 70:e47-56. [DOI: 10.1055/s-2008-1080933] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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46
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Establishment of a lung cancer biopsy tissue bank. Lung Cancer 2008. [DOI: 10.1016/s0169-5002(08)70025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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47
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Developing core sets for persons with bipolar disorder based on the International Classification of Functioning, Disability and Health. Bipolar Disord 2007; 9:16-24. [PMID: 17391346 DOI: 10.1111/j.1399-5618.2007.00322.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION Functioning is increasingly being taken into account when assessing the impact of bipolar disorder (BD) on the individual, as well as the effectiveness of treatments. With the International Classification of Functioning, Disability and Health (ICF), we can now rely on a globally agreed-upon framework and system for classifying the typical spectrum of problems in functioning, given the environmental context in which subjects live. ICF Core Sets are subgroups of ICF items selected to capture those aspects of functioning that are most likely to be affected by specific disorders. Within a given disorder, both Brief and Comprehensive Core Sets can be established to serve specific purposes. OBJECTIVE The aim of this paper is to outline the development process of the ICF Core Sets for BD. METHODS The final definition of ICF Core Sets for BD will be determined at an ICF Core-Sets Consensus Conference, which will integrate evidence from preliminary studies, namely (a) semi-structured interviews with people with BD in different countries, (b) a Delphi exercise with international experts participating and (c) a cross-sectional study. CONCLUSION ICF Core Sets are being designed with the goal of providing useful standards for research, clinical practice and teaching. We believe that these ICF Core Sets for BD will stimulate research leading to improved understanding of functioning, disability and health in BD. Such research, we hope, will lead to interventions and accommodations to improve restoration and maintenance of functioning and minimise disability among people with BD throughout the world.
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Self-generation of concentration gradients of divalent cations in commercial bentonite membrane during ultrafiltration. J Colloid Interface Sci 2006; 304:530-4. [PMID: 17046781 DOI: 10.1016/j.jcis.2006.09.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 09/13/2006] [Accepted: 09/15/2006] [Indexed: 11/20/2022]
Abstract
Research workers, working with commercial bentonite-based membranes, reported different diffusivity for co- and counterions through those membranes. Many of these researchers called this difference in diffusivity ultrafiltration. Some of these workers also noted that commercial bentonite membranes often contain divalent metal carbonates as impurities. Recently it has been suggested that the ultrafiltration is associated with the co-diffusion of divalent metal ions. Previous workers did not recognize this co-diffusion, probably due to an absence of imposed concentration gradient for the divalent metal ions. The present investigation suggests that the required concentration gradient is self-generated by increased solubility of the divalent metal carbonates with increasing concentration of alkali halide in solution. The presence of dissolved divalent metal ions alters the interfacial potentials at the outside solution and bentonite membrane junctions and reduces the electrostatic potential gradient across the membrane. A reduction in the electrostatic potential gradient across the membrane reduces the coupling between the diffusing co- and counterions and alters their diffusivity.
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[Applicability of the ICF in measuring functioning and disability in unipolar depression in Primary Care settings]. ACTAS ESPANOLAS DE PSIQUIATRIA 2006; 34:393-6. [PMID: 17117336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
INTRODUCTION We use the biopsychosocial model of the International Classification of Functioning, Disability, and Health (ICF): a) to analyze functioning and disability patterns in unipolar depression cases attended in primary care settings; b) to study predictive and mediator variables related to disability in depression, and c) to determine the impact of traditional interventions in depression cases using functional remission as outcome measure. DESIGN Naturalistic, prospective, longitudinal. SETTING Multicenter study in primary care. Health Area 2. Region of Madrid. PARTICIPANTS Adult patients with a diagnosis of unipolar depression who initiate psychopharmacological treatment with selective serotonin reuptake inhibitor (SSRI) in primary care sites. Patients with history of bipolar disorders, psychotic disorders, dementias, and dependence of toxic substances will be excluded. MAIN MEASUREMENTS Level of functioning and disability in different domains of well-being assessed through ICF related instruments. Stressful life events, social support and cognitive schemes will be analyzed as mediator variables. Socio-demographic and clinical characteristics, psychopharmacological treatment and treatment compliance are considered independent factors. DISCUSSION AND PRACTICAL USE: Selection bias may affect the generalization of the results. The biopsychosocial model underlying the ICF and its methodology are applied to the study of depression in primary care settings for the first time in Spain. Improving our understanding of disability related factors in depressive patients is expected. This study is one of the main research priorities of the EU (MHADIE project).
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Aspects of ionic diffusion through thick matrices of charged particles. J Colloid Interface Sci 2006; 300:820-5. [PMID: 16709418 DOI: 10.1016/j.jcis.2006.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Revised: 04/03/2006] [Accepted: 04/04/2006] [Indexed: 11/28/2022]
Abstract
A review of the literature on ionic diffusion through matrices of charged particles shows that many workers have reported higher diffusivity of co-ions than of counterions. If these observations are correct then the requirement of electroneutrality of bulk solutions is violated. In those experiments other, not looked for, ions must have been taking part. It therefore appears that complete chemical analyses of solutions of both up- and downstream sides should be carried out, otherwise misleading inferences may be drawn, with practical consequences. Some researchers have studied transport of water under osmotic pressure differentials across clay membranes. However, a diffusing ion, during its transport from higher concentration to lower concentration, always carries its water of hydration. This second water transport process has not received attention. This suggests that at a critical concentration two transport processes will cancel each other. Attention has been drawn to this second type of water flow and its consequences. In ionic diffusion, each side of the membrane-outside solution interface is subject to the effects of the Nernst layer and Donnan zone. However, these layers and zones are seldom treated quantitatively. This has been carried out in this paper by two different methods. Both methods give identical thicknesses of the Nernst layer and Donnan zone. Finally, the effects of the presence of soluble bivalent salts on the diffusivity of different types of ions have been commented up on. In these cases some of the co-ions diffuse to the upstream side.
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