The importance of the modular structure 'fluor-spacer-amine' is pointed out for the design of fluorescent molecular sensors for p H according to the principle of photoinduced electron transfer (PET). Anthracen-9-yl methylamines (24) and some azacrown ether analogues (1 5 and 23) are examined in this context. They show p H -dependent fluorescence quantum yields describable by eqn. ( 5) while all other electronic spectral parameters remain essentially pH-invariant. The range of pK, values of these sensors are understandable in terms of macrocyclic effects and the transmission of electric fields across the anthracene short axis. Phase-shift fluorometric determination of the fluorescence lifetimes of these sensors allows the calculation of the rate constant of PET in their proton-free form t o be 1 Ole-1 0" s-', with the diamines 23 and 24b exhibiting the faster rates.

BackgroundSchool health promotion has been shown to improve the lifestyle of students, but it remains unclear whether school-based programs can influence family health. We developed an innovative program that enables school children to act as change agents in promoting healthy lifestyles of their mothers. The objective of this study was to examine the effect of the child-initiated intervention on weight, physical activity and dietary habit of their mothers.MethodsA 12-month cluster randomized trial was conducted, with school as a cluster. Participants were mothers with grade 8 students, aged around 13 years, of 20 schools in Homagama, Sri Lanka. Students of the intervention group were trained by facilitators to acquire the ability to assess noncommunicable disease risk factors in their homes and take action to address them, whereas those of the comparison group received no intervention. Body weight, step count and lifestyle of their mothers were assessed at baseline and post-intervention. Multi-level multivariable linear regression and logistic regression were used to assess the effects of intervention on continuous and binary outcomes, respectively.ResultsOf 308 study participants, 261 completed the final assessment at 12 month. There was a significantly greater decrease of weight and increase of physical activity in the intervention group. The mean (95 % confidence interval) difference comparing the intervention group with the control group was −2.49 (−3.38 to −1.60) kg for weight and −0.99 (−1.40 to −0.58) kg/m2 for body mass index. The intervention group had a 3.25 (95 % confidence interval 1.87–5.62) times higher odds of engaging in adequate physical activity than the control group, and the former showed a greater number of steps than the latter after intervention. The intervention group showed a greater reduction of household purchase of biscuits and ice cream.ConclusionsA program to motivate students to act as change agents of family’s lifestyle was effective in decreasing weight and increasing physical activity of their mothers.Trial registrationSri Lanka Clinical Trials Registry SLCTR/2013/011.Electronic supplementary materialThe online version of this article (doi:10.1186/s12966-016-0369-7) contains supplementary material, which is available to authorized users.

Objectives To investigate the prevalence and consumption of tobacco and alcohol among males in the Colombo and Polonnaruwa districts. Design A cross-sectional study based on multistage cluster sampling was carried out in four Medical Officer of Health (MOH) areas in the Colombo (urban) and Polonnaruwa (rural) districts to assess the prevalence of tobacco and alcohol use. The Public Health Midwife areas were considered as primary clusters. The sample consisted of males over 18 years. There were 1318 from the Colombo District and 1366 from the Polonnaruwa

The poor spent less than those with higher income on alcohol and tobacco, but the expenditure constituted a much larger slice of their income thus compromising their ability to meet basic needs. In low-income countries, damaging economic consequences start at lower levels of alcohol and tobacco consumption and affect a significant proportion of the population. Defining risk levels and guidelines on safe limits based purely on individual health harm has, at best, little meaning in such settings.

Background Mobilising non-professional health workers has been successful in improving community health, but the effectiveness of an education program targeting youths in a community-based approach remains unclear. The objective of this study was to investigate the effect of an intervention with youth on cardiovascular disease risk factors of community adults. Methods A 12-month cluster randomised trial was conducted in a semi-urban area of Colombo in Sri Lanka. Facilitators trained youth club members aged 15–29 years to assess cardiovascular disease risk factors and take actions in the community to address relevant issues. The control group received no intervention. Body weight and blood pressure as primary outcomes and lifestyle of adults as secondary outcomes were measured pre- and post-intervention. Multilevel linear and logistic regressions were used to assess the effects of the intervention on changes in continuous and binary outcomes, respectively, from baseline to endpoint. Results Of 512 participants at baseline, 483 completed the final assessment after the intervention. Regarding primary outcomes, the intervention group showed a significantly greater decrease in body weight after intervention than the control group. The mean (95% confidence interval) difference of body weight change for intervention versus control group was − 2.83 kg (− 3.31, − 2.35). There was no statistically significant difference in blood pressure between the two groups. Turning to the secondary outcomes, in diet, the intervention group had a higher probability of consuming at least one serving/day of fruits ( p = 0.02) and a lower probability of consuming snacks twice/day or more ( p < 0.001) than the control group. Conclusions An intervention employing youths as change agents was effective in lowering body weight among community adults in Sri Lanka. Trial registration Trial registration number: SLCTR/2017/002 , Name of registry: Sri Lanka Clinical Trials Registry, Date of registration: 19th January 2017, Date of enrolment of the first participant to the trial: 1st February 2017. Electronic supplementary material The online version of this article (10.1186/s12889-019-7142-1) contains supplementary material, which is available to authorized users.