Circulating acetylcholine serves as a potential biomarker role in pulmonary hypertension.

BACKGROUND: An increased acetylcholine (ACh) level in the right ventricle tissue of pulmonary hypertension (PH) was revealed, which indicated the important role of ACh in disease pathogenesis. However, the relationship between plasma ACh levels and disease conditions and patients' prognosis has not been investigated. We aimed to explore the association between plasma ACh levels and the prognosis of patients with PH. We also discussed the feasibility of plasma ACh as a biomarker, which may contribute to the management of PH patients in the future. METHODS: Patients with confirmed PH in Fuwai Hospital from April 2019 to August 2020 were enrolled. The primary clinical outcome in this study was defined as a composite outcome, including death/lung transplantation, heart failure, and worsening of symptoms. Fasting plasma was collected to detect the ACh levels. The association between ACh levels and patients' prognosis was explored. RESULTS: Finally, four hundred and eight patients with PH were enrolled and followed for a mean period of 2.5 years. Patients in the high ACh group had worse World Health Organization Functional Class (WHO-FC), lower 6-minute walk distance (6 MWD), and higher N-terminal pro-brain natriuretic peptide (NT-proBNP). Notably, echocardiographic and hemodynamic parameters in the high metabolite group also suggested a worse disease condition compared with the low ACh group. After adjusting for confounders, compared with low ACh patients, those with high metabolite levels still have worse prognoses characterized as elevated risk of mortality, heart failure, and symptoms worsening. CONCLUSION: High circulating ACh levels were associated with severe PH conditions and poor prognosis, which might serve as a potential biomarker in PH.

Public awareness of war on diabetes campaign and its association with behavioural outcomes.

The War on Diabetes campaign was launched in 2016, encouraging Singapore residents to engage in regular exercise, adopt healthy dietary habits and screen for early detection of diabetes. This study aims to examine campaign awareness and its associations with sedentary behaviour, dietary habits and identifying diabetes. Data were obtained from the nationwide Knowledge, Attitudes and Practices study on diabetes in Singapore. A total of 2895 participants responded to a single question assessing campaign awareness. The Dietary Approaches to Stop Hypertension (DASH) diet screener assessed dietary habits, and the Global Physical Activity Questionnaire (GPAQ) measured sedentary behaviour. Recognition of diabetes was established using a vignette depicting a person with diabetes mellitus. Logistic and linear regression models were used to measure the associations. Most participants were 18- to 34-years old (29.9%) and females (51.6%). About 57.4% identified the campaign. Campaign awareness exhibited positive associations with identifying diabetes based on the vignette [odds ratio (OR): 1.5; 95% confidence interval (CI): 1.1-2.2; P = 0.022], lower odds of sedentary behaviour ≥7 h/day (OR: 0.7; CI: 0.5-0.9; P = 0.018) and higher DASH scores (ß = 1.3; P < 0.001). The study recognized early significant associations between the behavioural outcomes and the campaign, emphasizing the need for ongoing campaign sustainability and evaluation of its long-term impact on population health.

Ab initio simulations of ultrashort laser pulse interaction with Cl-Si(100): implications for atomic layer etching.

Due to the remarkable resistance of SiCl against photo-induced desorption, achieving atomic layer etching (ALE) of Cl-Si(100) through a laser-based method has remained a formidable challenge. In this study, we investigate the interaction between ultrashort laser pulses and the Cl-Si(100) surface via ab initio simulations that combine real-time time-dependent density functional theory and molecular dynamics. Our results demonstrate the direct desorption of the stubborn SiCl layer through the application of appropriate femtosecond laser pulses. Notably, the desorption process is enhanced by pulses with higher laser intensity, shorter wavelength, and longer pulse duration. There is a threshold intensity beyond which the SiCl can be directly desorbed under laser pulses with a wavelength of 488 nm and a pulse duration of 40 ℏ eV-1 (26.3 fs). Analysis of electron localization function reveals a critical bond breaking length of 2.98 Šbetween Si-Si, connecting SiCl to the bulk material. The time evolution of bond lengths and forces reveals that the desorption of SiCl is primarily driven by repulsive forces generated within the Si-Si bond. Furthermore, electron density difference analysis and Keldysh factor calculations indicate that these repulsive forces arise from multiphoton ionization. This study provides crucial atomic-level insights into the interaction of ultrashort laser pulses with Cl-Si(100), thereby propelling the advancement of laser-induced atomic layer etching techniques.

HIV gp120/Tat protein-induced epithelial-mesenchymal transition promotes the progression of cervical lesions.

BACKGROUND: Human immunodeficiency virus (HIV) infection is associated with an elevated incidence of cervical cancer, and accelerated disease progression, but the underlying mechanisms are not well understood. This study aimed to investigate the relationship between HIV infection and epithelial-mesenchymal transition (EMT) in cervical cancer. METHODS: Tissue samples from HIV-positive and negative patients with cervical intraepithelial neoplasia (CIN) and cervical cancer were analyzed for EMT-related proteins. Human cervical cancer SiHa cells were treated with HIV Tat and gp120 proteins to test their effects on EMT, migration, and invasion. RESULTS: HIV-positive patients had lower E-cadherin and cytokeratin, and higher N-cadherin and vimentin levels than HIV-negative patients. HIV Tat and gp120 proteins induced EMT, migration, and invasion in SiHa cells. Transcriptome sequencing analysis revealed that, compared to the control group, the protein-treated group showed upregulation of 22 genes and downregulation of 77 genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed the involvement of the Wnt signaling pathway in EMT. Further analysis of gene expression related to this pathway revealed upregulation of DVL1, TCF7, KRT17, and VMAC, while GSK3ß, SFRP2, and CDH1 were downregulated. Immunofluorescence assay demonstrated that HIVgp120 and Tat proteins treatment induced elevated ß-catenin expression with nuclear accumulation in SiHa cells. CONCLUSIONS: The treatment of SiHa cells with HIV Tat and gp120 proteins induces EMT and activates the Wnt/ß-catenin pathway, suggesting that the Wnt/ß-catenin pathway may play a crucial role in promoting EMT progression in cervical lesion tissues of HIV-infected patients.

Measuring social desirability bias in a multi-ethnic cohort sample: its relationship with self-reported physical activity, dietary habits, and factor structure.

BACKGROUND: Social desirability bias is one of the oldest forms of response bias studied in social sciences. While individuals may feel the need to fake good or bad answers in response to sensitive or intrusive questions, it remains unclear how rampant such a bias is in epidemiological research pertaining to self-reported lifestyle indicators in a multicultural Asian context. The main purpose of the current study is, therefore, to examine the sociodemographic correlates and impact of social desirability responding on self-reported physical activity and dietary habits at an epidemiological scale in a non-western multi-cultural Asian setting. METHODS: Prior to the main analyses, confirmatory and exploratory factor analyses were conducted to determine the factorial validity of a western derived concept of social desirability. Multiple regression analyses were conducted on cross-sectional data (n = 2995) extracted from a nationwide survey conducted between 2019 and 2020. RESULTS: A unique factor structure of social desirability was found and was therefore used for subsequent analyses. Multiple regression analyses revealed older age groups, the Indian ethnic group, those with past or present marriages, and having no income, had a significantly greater tendency to act on the bias. CONCLUSION: The construct of social desirability bias was fundamentally different in a multicultural context than previously understood. Only a small proportion of variance of self-report lifestyle scores was explained by social desirability, thus providing support for data integrity.

High fibrinogen-to-albumin ratio with type 2 diabetes mellitus is associated with poor prognosis in patients undergoing percutaneous coronary intervention: 5-year findings from a large cohort.

BACKGROUND: Inflammation plays a crucial role in coronary atherosclerosis progression, and growing evidence has demonstrated that the fibrinogen-to-albumin ratio (FAR), as a novel inflammation biomarker, is associated with the severity of coronary artery disease (CAD). However, the long-term risk of cardiovascular events remains indistinct in patients with different level of FAR and different glycemic metabolism status. This study was to assess 5-year clinical outcomes of diabetic and non-diabetic patients who underwent percutaneous coronary intervention (PCI) with different level of FAR. METHODS: We consecutively enrolled 10,724 patients with CAD hospitalized for PCI and followed up for the major adverse cardiac and cerebrovascular events (MACCE) covering all-cause mortality, cardiac mortality, non-fatal myocardial infarction, non-fatal ischemic stroke, and unplanned coronary revascularization. FAR was computed using the following formula: Fibrinogen (g/L)/Albumin (g/L). According to the optimal cut-off value of FAR for MACCE prediction, patients were divided into higher level of FAR (FAR-H) and lower level of FAR (FAR-L) subgroups, and were further categorized into four groups as FAR-H with DM and non-DM, and FAR-L with DM and non-DM. RESULTS: 5298 patients (58.36 ± 10.36 years, 77.7% male) were ultimately enrolled in the present study. A total of 1099 (20.7%) MACCEs were documented during the 5-year follow-up. The optimal cut-off value of FAR was 0.0783 by the surv_cutpoint function. Compared to ones with FAR-H and DM, patients with FAR-L and non-DM, FAR-H and non-DM, FAR-L and DM had decreased risk of MACCEs [adjusted hazard ratio (HR): 0.75, 95% confidence interval (CI) 0.64-0.89, P = 0.001; HR: 0.78, 95% CI 0.66-0.93, P = 0.006; HR: 0.81, 95% CI 0.68-0.97, P = 0.019; respectively]. Notably, non-diabetic patients with lower level of FAR also had lower all-cause mortality and cardiac mortality risk than those in the FAR-H/DM group (HR: 0.41, 95% CI 0.27-0.63, P < 0.001; HR: 0.30, 95% CI 0.17-0.53, P < 0.001; respectively). Multivariate Cox proportional hazards regression analysis also indicated the highest risk of MACCEs in patients with FAR-H and DM than others (P for trend = 0.005). In addition, post-hoc analysis revealed consistent effects on 5-year MACCE across various subgroups. CONCLUSION: In this real-world cohort study, higher level of FAR combined with DM was associated with worse 5-year outcomes among patients with CAD undergoing PCI. The level of FAR may help to identify high-risk individuals in this specific population, where more precise risk assessment should be performed.

Modification Mechanism of Polyamide Reverse Osmosis Membrane by Persulfate: Roles of Hydroxyl and Sulfate Radicals.

Oxidative modification is a facile method to improve the desalination performance of thin-film composite membranes. In this study, we comparatively investigated the modification mechanisms induced by sulfate radical (SO4• -) and hydroxyl radical (HO•) for polyamide reverse osmosis (RO) membrane. The SO4• -- and HO•-based membrane modifications were manipulated by simply adjusting the pH of the thermal-activated persulfate solution. Although both of them improved the water permeability of the RO membrane under certain conditions, the SO4• --modified membrane notably prevailed over the HO•-modified one due to higher permeability, more consistent salt rejection rates over wide pH and salinity ranges, and better stability when exposed to high doses of chlorine. The differences of the membranes modified by the two radical species probably can be related to their distinct surface properties in terms of morphology, hydrophilicity, surface charge, and chemical composition. Further identification of the transformation products of a model polyamide monomer using high-resolution mass spectrometry demonstrated that SO4• - initiated polymerization reactions and produced hydroquinone/benzoquinone and polyaromatic structures; whereas the amide group of the monomer was degraded by HO•, generating hydroxyl, carboxyl, and nitro groups. The results will enlighten effective ways for practical modification of polyamide RO membranes to improve desalination performances and the development of sustainable oxidation-combined membrane processes.

Membrane Scaling and Wetting in Membrane Distillation: Mitigation Roles Played by Humic Substances.

Membrane scaling and wetting severely hinder practical applications of membrane distillation (MD) for hypersaline water/wastewater treatment. In this regard, the effects of feedwater constituents are still not well understood. Herein, we investigated how humic acid (HA) influenced gypsum-induced membrane scaling and wetting during MD desalination. At low concentrations (5-20 mg L-1), HA notably mitigated membrane scaling and wetting. The morphological characterization of scaled membranes revealed that the antiwetting behavior could be ascribed to the formation of a compact and protective gypsum/HA scale layer, which blocked the flow channel of scaling ions and suppressed the intrusion of scale particles into membrane pores. Based on the comprehensive analysis of the scaling process, the formation of the scale layer was related to the heterogeneous crystallization of gypsum on the membrane surface. Moreover, deprotonated HA interfered with the heterogeneous crystallization process by inhibiting the formation of gypsum nuclei and altering the orientation of crystal growth, thus delaying membrane scaling and altering the morphology of the scale layer. Thermodynamic and kinetic analyses further demonstrated the mitigation mechanism of HA. Furthermore, improved fouling reversibility and antiwetting ability in synthetic seawater treatment endowed by HA were observed. This study provides new insight into the roles played by the organic constituents of water/wastewater during membrane desalination, providing a valuable reference for developing novel strategies to improve the performance of MD.

Associations of lipid measures with total occlusion in patients with established coronary artery disease: a cross-sectional study.

BACKGROUND: Total occlusion is the most severe coronary lesion, indicating heavy ischemic burden and poor prognosis. The lipid profile is central to the development of atherosclerotic coronary lesions. Evidence on the optimal lipid measure to be monitored and managed in patients with established coronary artery disease (CAD) is inconclusive. METHODS: Total cholesterol (TC), total triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), nonhigh-density lipoprotein cholesterol (non-HDL-c), lipoprotein (a) [Lp(a)], apolipoprotein B (apoB), non-HDL-c/HDL-c, and apoB/apoA-1 were analyzed in quintiles and as continuous variables. The associations of lipid measures with total occlusion were tested using logistic regression models, visualized with restricted cubic splines, and compared by areas under the receiver operating characteristic curves (AUROC). Discordance analysis was performed when apoB/apoA-1 and non-HDL-c/HDL-c were not in concordance. RESULTS: The prospective cohort study included 10,003 patients (mean age: 58 years; women: 22.96%), with 1879 patients having total occlusion. The risks of total occlusion significantly increased with quintiles of Lp(a), non-HDL-c/HDL-c, and apoB/apoA-1 (all p for trend < 0.001). TG had no association with total occlusion. Restricted cubic splines indicate significant positive linear relations between the two ratios and total occlusion [odds ratio per 1-standard deviation increase (95% confidence interval): non-HDL-c/HDL-c: 1.135 (1.095-1.176), p < 0.001; apoB/apoA-1: 2.590 (2.049-3.274), p < 0.001]. The AUROCs of apoB/apoA-1 and non-HDL-c/HDL-c were significantly greater than those of single lipid measures. Elevation in the apoB/apoA-1 tertile significantly increased the risk of total occlusion at a given non-HDL-c/HDL-c tertile but not vice versa. CONCLUSION: ApoB/apoA-1 confers better predictive power for total occlusion than non-HDL-c/HDL-c and single lipid measures in established CAD patients.

The impact of having foreign domestic workers on informal caregivers of persons with dementia - findings from a multi-method research in Singapore.

BACKGROUND: Informal caregivers of persons with dementia (PWDs) sometimes engage foreign domestic workers (FDWs) to support their caregiving journey. However, there has not been much research to establish if this is really beneficial. The current study aims to investigate whether engaging FDWs specifically for caregiving of PWDs truly moderates caregiver stress and to explore caregivers' experiences of engaging FDWs. METHODS: A multi-method study design with a quantitative and qualitative sub-study was adopted. For the quantitative sub-study, 282 informal caregivers of PWDs were recruited. Propensity score matching analysis was used. For the qualitative sub-study, 15 informal caregivers with FDWs were interviewed. Inductive thematic analysis was conducted. RESULTS: The quantitative sub-study confirmed that engaging FDWs did moderate the depressive symptoms of informal dementia caregivers (marginal effect = -3.35, p = 0.0497). However, such support did not affect their caregiving burden, self-efficacy, and perceived positive aspects of caregiving. The qualitative sub-study suggested that engaging FDWs is an ambivalent experience, which entails both support and challenges. CONCLUSIONS: The current study confirmed previous research findings, that engaging FDWs moderated depressive symptoms among caregivers of PWDs, and it could be through their physical support such as in daily caregiving activities. Policy-makers may consider providing more subsidies to caregivers caring for PWDs with mobility issues to hire FDWs. They may also consider providing training to FDWs on dementia caregiving skills and improving the intake of such training as this might be helpful for both FDWs and caregivers during this journey.

Factors influencing uptake of diabetes health screening: a mixed methods study in Asian population.

BACKGROUND: Health screens are the cornerstones for health promotion and preventive interventions at a community level. This study investigated the barriers and facilitators to the uptake of diabetes health screening in the general population of Singapore. METHODS: In this mixed methods study, participants without diabetes were recruited from the general population. The quantitative phase (n = 2459) included face to face survey of participants selected through disproportionate stratified random sampling. Those who participated in the quantitative survey were then randomly chosen for a one-to-one semi-structured interview (n = 30). RESULTS: Among the survey respondents, 73.09% (n = 1777) had attended a diabetes health screening in their lifetime whilst 42.36% (n = 1090) and 57.64% (n = 1328, p < 0.0001) attended the health screens regularly (every 12 months) and irregularly, respectively. A significantly higher proportion of older adults (≥ 40 years) attended regular diabetes health screening compared to younger adults (less than 40 years; 55.59% vs 24.90%, p < 0.001). The top 3 reasons for attending regular health screens were to detect diabetes early, to make lifestyle changes in case of a diagnosis and being health conscious. Qualitative interviews identified similar issues and complex nuances that influenced the uptake of regular diabetes health screening. Several personal factors (laziness, self-reliance, psychological factors, etc.), competing priorities, fatalistic beliefs, affordability, misconceptions about the screens, and appointment related factors (inconvenient location, time, etc.) were identified as barriers, while affordable screens, sense of personal responsibility, perception of susceptibility /risk, role of healthcare team (e.g. reminders and prescheduled appointments) and personal factors (e.g. age, family, etc.) were facilitators. Age, household income, ethnicity and educational level were associated with the uptake of regular diabetes health screening. CONCLUSION: The uptake of regular diabetes health screening can be improved. Several barriers and enablers to the uptake of diabetes health screening were identified which should be addressed by the policy makers to alleviate misconceptions and create greater awareness of the importance of the programme that will improve participation.

A cross-sectional study on the perceived barriers to physical activity and their associations with domain-specific physical activity and sedentary behaviour.

BACKGROUND: Physical inactivity and sedentary behaviour have detrimental consequences to the individual and the economy. Our study examined the prevalence of perceived barriers to physical activity in Singapore's adult population and their associations with physical activity and sedentary behaviour. METHODS: This cross-sectional analysis utilised data from a nationwide survey in Singapore. Participants (n = 2867) were recruited from February 2019 to March 2020. The independent variables were internal (e.g. fatigue, age) and external (e.g. weather, cost) perceived barriers to physical activity. The outcomes were domain-specific physical activity (work, transport and leisure) and sedentary behaviour, all of which were assessed using the Global Physical Activity Questionnaire. The associations were examined using zero-inflated negative binomial regressions for physical activity and linear regression for sedentary behaviour. RESULTS: The median (Interquartile range) for work-related, transport-related and leisure-related physical activity were 0 (0 - 1440), 600 (160 - 1120) and 360 (0 - 1080) MET (metabolic equivalent)-minutes per week. The median sedentary behaviour (IQR) was 360 (240 - 540) minutes per day. The top three barriers were lack of time (65.3%), fatigue (64.7%) and pollution (56.1%). After adjustment, the level of transport-related physical activity was lower for respondents who cited lacking pavement or parks as a barrier, but higher for those who indicated cost and safety concerns. Respondents who reported pollution as a barrier were more likely to engage in transport-related physical activity. The level of leisure-related physical activity was lower for respondents indicating weather, lack of time and age as barriers, but higher for those reporting safety concerns. The odds of engaging in leisure-related physical activity was lower for those citing age, cost and fatigue as barriers, but higher for those indicating the weather. Sedentary behaviour was positively associated with work and limited accessibility to exercise facilities, but negatively with safety concerns. CONCLUSION: Individuals can be motivated to overcome internal barriers (fatigue, lack of time, cost and age) through social support and emphasis on exercise benefits. External barriers (weather and lack of pavements or parks) can be reduced by raising awareness of existing infrastructure. Sedentary behaviour can be improved by implementing workplace measures, such as reducing the time spent sitting.

Acceptance of healthy lifestyle nudges in the general population of Singapore.

BACKGROUND: In recent years, behaviourally driven policies such as nudges have been increasingly implemented to steer desired outcomes in public health. This study examines the different nudges and the socio-demographic characteristics and lifestyle behaviours that are associated with public acceptance of lifestyle nudges. METHODS: The study used data from the nationwide Knowledge, Attitudes and Practices study (KAP) on diabetes in Singapore. Three types of nudges arranged in increasing order of intrusiveness were examined: (1) information government campaigns, (2) government mandated information and (3) default rules and choice architecture. Acceptance was assessed based upon how much respondents 'agreed' with related statements describing heathy lifestyle nudges. Multivariable linear regressions were performed with socio-demographics and lifestyle behaviours using scores calculated for each nudge. RESULTS: The percentage of respondents who agreed to all statements related to each nudge were: 75.9% (information government campaigns), 73.0% (government mandated information), and 33.4% (default rules and choice architecture). Respondents of Malay/Others ethnicity (vs. Chinese) were more likely to accept information government campaigns. Respondents who were 18 - 34 years old (vs 65 years and above), female, of Malay/Indian ethnicity (vs Chinese), were sufficiently physically active, and with a healthier diet based on the DASH (Dietary Approach to Stop Hypertension) score were more likely to accept nudges related to government mandated information. Respondents of Malay/Indian ethnicity (vs Chinese), and who had a healthier diet were more likely to accept default rules and choice architecture. CONCLUSION: Individuals prefer less intrusive approaches for promoting healthy lifestyle. Ethnicity and lifestyle behaviours are associated with acceptance of nudges and should be taken into consideration during the formulation and implementation of behaviourally informed health policies.

Sources of information on diabetes and its demographic correlates: a nationwide survey among Singapore residents.

Diabetes is a major public health concern in Singapore, and the Singapore Government declared a 'War on Diabetes', which included a nationwide public health campaign. It is important to identify what sources of diabetes information reach the general population, whether this differs by socio-demographic characteristics and if the sources of information influence knowledge of diabetes to aid the successful dissemination of health information. Two thousand eight hundred ninety-five respondents were part of a population-based cross-sectional study conducted from February 2019 to September 2020. Respondents rated on a five-point scale whether they had obtained information on diabetes from eight different information sources, and responses were dichotomized into 'endorsed receiving information' or 'not endorsed receiving information'. Poisson regression models were conducted with the 'endorsement of receiving information' from each source as the outcome and socio-demographic variables as predictors. 95.9% of the study population had received information on diabetes from at least one source, and the mean number of sources was 4.2 ± 2.0. The leading source was media articles (82.1%), followed by health promotion videos/advertisements (77.9%), online websites (58.5%), books (56.5%), healthcare professionals (55.0%), radio (54.4%), public forums (27.7%) and support groups (15.5%). Endorsing a greater number of informational sources was associated with being younger, belonging to Malay or Indian instead of Chinese ethnicity, and having diabetes. An intensive nationwide diabetes awareness campaign successfully reached the public in Singapore with specific sources of information depending on socio-demographic characteristics. Findings suggest that diabetes information campaigns should utilize multiple channels for dissemination considering the different socio-demographic subgroups.

Physical activity, sedentary behaviour and smoking status among psychiatric patients in Singapore - a cross-sectional study.

BACKGROUND: Unhealthy behaviours such as physical inactivity, sedentary behaviour and smoking have been found to be more prevalent in people with psychiatric disorders than in the general population, leading to increased mortality risk. The present study seeks to identify correlates of physical activity and sedentary behaviour among psychiatric patients in Singapore, as well as investigate differences in their physical activity patterns by smoking status. METHODS: Participants (n = 380) were recruited from a tertiary psychiatric hospital in Singapore as part of a study on the prevalence and correlates of smoking among psychiatric patients. Physical activity levels and sedentary behaviour were measured using the Global Physical Activity Questionnaire (GPAQ) and analysed based on GPAQ guidelines. Chi-square analyses were conducted to examine differences in physical activity by smoking status, and logistic regression analyses to yield sociodemographic correlates of meeting physical activity guidelines (as recommended by the World Health Organization) and sedentary behaviour. RESULTS: Education was found to be significantly associated with meeting recommended physical activity levels, while age and marital status were significantly associated with excessive sedentary behaviour. Additionally, while no significant differences were found among current, former and non-smokers across all types of physical activity engagement levels, there was a high prevalence of inadequate physical activity (43.2%) and excessive sedentary behaviour (38.8%) among participants. CONCLUSION: Given the high prevalence of inadequate physical activity and excessive sedentary behaviour among current, former and non-smokers with psychiatric disorders, programmes aimed at increasing physical activity and lowering sedentary behaviour levels should be integrated into targeted treatment plans to improve clinical outcomes.

Factors associated with caregiving self-efficacy among primary informal caregivers of persons with dementia in Singapore.

BACKGROUND: Informal caregivers of persons with dementia (PWD) are often associated with negative health outcomes. Self-efficacy in dementia caregiving has been reported to have protective effects on caregiver's health. This study aims to examine the factors associated with the domains of caregiving self-efficacy among informal caregivers in Singapore, a country with a rapidly aging population and a 10% prevalence of dementia among older adults. METHODS: Two hundred eighty-two informal caregivers were recruited and data including participant's caregiving self-efficacy, sociodemographic information, perceived social support, positive aspects of caregiving, knowledge of dementia, as well as behavioral and memory problems of care recipients were collected. A confirmatory factor analysis (CFA) was performed for the 3-factor model of the Revised Scale for Caregiving Self-Efficacy (RSCSE), and multiple linear regressions were conducted using the RSCSE subscales as dependent variables. RESULTS: Our CFA found that the RSCSE 3-factor model proposed by the original scale developer was an acceptable fit among informal caregivers in Singapore. Having established that the 3-factor model of the RSCSE was compatible among our sample, a series of multiple regressions were conducted using each of the factors as a dependent variable. Regressions revealed several factors that were significantly associated with caregiving self-efficacy. Importantly, outlook on life was positively associated to all 3 domains of the RSCSE, while social support was positively associated with self-efficacy in obtaining respite and controlling upsetting thoughts. CONCLUSION: The 3-factor model of the RSCSE was found to be an appropriate fit for our sample. Findings from this study elucidated important novel insights into the factors that influences caregiving self-efficacy amongst informal caregivers in Singapore. Crucially, caregivers' outlook on life and social support should be improved in order to enhance their caregiving self-efficacy.

Combining a variable-centered and a person-centered analytical approach to caregiving burden - a holistic approach.

BACKGROUND: Informal caregivers of persons with dementia often experience elevated levels of caregiving burden. However, existing studies tend to use a variable-centered approach to explore it. This study aims to understand the caregiving burden of informal caregivers of persons with dementia in Singapore through a combination of variable-centered and person-centered analytical approaches, and explore the correlates of identified factors and latent classes of caregiving burden. METHODS: Zarit Burden Interview was used to gauge the caregiving burden of 282 primary informal caregivers of persons with dementia recruited through convenience sampling in Singapore. Factor analysis and latent class analysis were conducted to identify the latent factors and the latent classes of Zarit Burden Interview, followed by multiple linear regression and multinomial logistic regression to explore their significant correlates. RESULTS: The analyses suggested a 17-item 3-factor structure for Zarit burden interview and three mutually exclusive caregiving burden classes. Regression analyses found that caregiving related variables especially care recipients' memory and behaviour problems were correlated with both the factors and latent classes of caregiving burden. CONCLUSIONS: The combination of these two approaches suggests that caregivers experiencing higher burden on one domain are likely to experience higher burden on the other two domains. This further supports the point that more attention should be given to caregivers who experience an overall high burden. Future research could explore the generalizability of our findings among caregivers elsewhere and explore the type of support needed by caregivers, especially those experiencing high burden.

Prevalence and patterns of physical activity, sedentary behaviour, and their association with health-related quality of life within a multi-ethnic Asian population.

OBJECTIVE: The study aimed to examine the prevalence and sociodemographic correlates of physical activity and sedentary behaviour in the general population of the multi-ethnic nation of Singapore as part of the Knowledge, Practice and Attitudes towards Diabetes study, a cross-sectional and population-based survey. It also examined the relationship between physical activity, sedentary behaviour, and health-related quality of life (HRQoL). METHODS: Physical activity and sedentary behaviour were assessed via the Global Physical Activity Questionnaire (GPAQ), while physical and mental HRQoL was assessed via the Short Form Health Survey (SF-12v2). Survey weights were employed to account for complex survey design. Multivariable logistic regression models were utilized to examine sociodemographic correlates of physical activity (insufficient vs. sufficient physical activity) and sedentary behaviour (< 7 h/day vs ≥7 h/day). Descriptive statistics were calculated to examine the percentage of time spent in different domains of physical activity. Multivariable linear regressions were conducted to examine the association between physical activity and sedentary behaviour with physical and mental HRQoL. RESULTS: Two thousand eight hundred sixty seven participants recruited from February 2019 to March 2020 (prior to COVID-19 lockdown and related restrictions in Singapore) were included in the analyses. 83.3% of respondents had sufficient physical activity. Age (65 years and above) and income (SGD 2000 to 3999) were associated with a higher likelihood of insufficient physical activity. In contrast, those of Malay ethnicity and having one chronic physical condition were associated with a lower likelihood of insufficient physical activity. 47.7% reported that they had sedentary behaviour of ≥7 h/day. Older age and a primary school education were related to a lower likelihood of sedentary behaviour, while being single, having higher income, obesity, and multimorbidity were associated with higher sedentary behaviour. Insufficient physical activity was significantly associated with lower physical HRQoL but was not significantly associated with mental HRQoL. Sedentary behaviour was not significantly associated with mental or physical HRQoL. CONCLUSION: About 17% of the population did not meet the minimum requirements for physical activity, while around half of the population spent a considerable time being sedentary. As insufficient physical activity was associated with poorer physical HRQoL, policymakers should promote moderate physical activity and encouraging the breaking up of prolonged sedentary periods within the middle- and high-income groups, especially at the workplace. Increased leisure-time exercise should be encouraged for those in the lower- income group.

Dementia knowledge and its demographic correlates amongst informal dementia caregivers in Singapore.

Objectives: The Dementia Knowledge Assessment Scale (DKAS) is a validated assessment tool to measure dementia knowledge. However, the factor structure of the DKAS has yet to be validated in Singapore. This study aims to investigate the DKAS factor structure amongst a sample of informal dementia caregivers in Singapore, as well as their sociodemographic correlates.Methods: A total of 282 participants were evaluated on their knowledge of dementia by an interviewer administering the DKAS. Confirmatory factor analysis (CFA) of factor models proposed by previous study yielded poor fit for our sample. Thus, an exploratory factor analysis (EFA) was conducted. Multiple linear regression was then performed to examine the sociodemographic correlates of DKAS factors.Results: EFA revealed a 23-item 3-factor model - 'misconceptions about dementia' (MD), 'caregiving considerations towards dementia' (CD) and 'dementia symptoms' (DS). Being a male caregiver and having lower educational levels were associated with poorer scores on MD and CD.Conclusion: A 3-factor model of the DKAS was found to be more appropriate with the sample in this study. Findings from this study suggests the need for more dementia literacy intervention for caregivers of dementia patients in Singapore, especially for male caregivers and those of lower education levels.

Utilization of Bidirectional Cation Transport in a Thin Film Composite Membrane: Selective Removal and Reclamation of Ammonium from Synthetic Digested Sludge Centrate via an Osmosis-Distillation Hybrid Membrane Process.

Selective removal and resource recovery of ammonium nitrogen (NH4+-N) from high-strength ammonium waste streams is of practical importance for biological wastewater treatment and environmental protection. In this study, we demonstrate the simultaneous removal and reclamation of ammonium from synthetic digested sludge centrate via a novel osmosis-distillation hybrid membrane (ODHM) process. Using NaHCO3 as the draw solute, ammonium diffuses from the synthetic centrate to the draw solution by utilizing the bidirectional cation transport nature of the thin film composite (TFC) membrane. Then, NH4+ is converted to gaseous NH3 at 60 °C and recovered by a sweeping gas membrane distillation (SGMD) process. Herein, the bidirectional transport of monovalent cations in the osmotic process, selectivity of TFC membranes for different cations, and recovery of the draw solution following the extraction of ammonia through the SGMD process were systematically investigated. The removal of NH4+-N from the synthetic centrate achieved 21.34% during a 6-h continuous operation of the ODHM system, with ammonium fluxes through the TFC and SGMD membranes at 1.39 and 0.57 mol m-2 h-1, respectively. A secondary interfacial polymerization was proposed to further enhance ammonium transport through the TFC membrane. Results reported here highlight the potential of the ODHM process for the selective removal and reclamation of ammonium from ammonium-rich waste streams.