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This study investigates households’ car ownership decisions in response to changes in vehicle quota control and transport infrastructure in Singapore. Unlike previous cross-sectional studies, we calibrate a dynamic car ownership model with a pseudo panel constructed from repeated cross-sectional travel surveys, controlling for the persistence of car ownership and unobserved heterogeneity. We find that the tightening of vehicle quota control and improved rail transit accessibility have reduced households’ desire to purchase cars. The long-run effect of these two policies is larger than their short-run effect due to the existence of true state dependence. The impact of expressway-network expansion is insignificant.

The increasing preference for ageing-in-place highlights the pivotal role of the neighbourhood environment in meeting the mobility needs of older adults. This paper examines the combined associations of objective and subjective measures of built environment features with older adults' travel pattern in Singapore. A multivariate ordered probit (OP) modelling framework is applied to examine older adults' daily trip frequency by four transport modes: walking, public bus, Mass Rapid Transit/Light Rapid Transit (MRT/LRT), and private motorized modes, while controlling for the correlations among the use of different modes. The results show that while perceived access to recreational facilities exert independent positive effects on older adults' daily walking trip frequency and enhance the effects of comparable objective measures, other subjective measures do not significantly moderate the effects of objective features on walking trip-making, including those of actual access to utilitarian destinations, the availability of sheltered walkways and unsafe pedestrian crossings near residence. The results also find independent positive effects of perceptions of transit proximity and comfortable and safe pedestrian connections on older adults’ daily transit trip-making.

Summary Background & aims Previous studies on the association between skipping breakfast and risk of cardiovascular disease and all cause mortality have drawn controversial conclusions. Therefore, we carried out a meta-analysis to illuminate this association. Methods Studies about the association between skipping breakfast and risk of cardiovascular disease and all cause mortality were identified by searching Pubmed, Embase, Cochrane, and Web of Science databases until June 2019. Then we screened articles for eligibility, extracted data, and pooled the results using a random-effects model. Results Seven cohort studies concerning a total of 221,732 participants were included in this meta-analysis. Skipping breakfast was associated with elevated risk of cardiovascular disease (relative risk 1.22 95% confidence interval 1.10–1.35) and all cause mortality (relative risk 1.25 95% confidence interval 1.11–1.40) compared with eating breakfast regularly. Conclusion Skipping breakfast increases the risk of cardiovascular disease and all cause mortality. Eating breakfast regularly may promote cardiovascular health and decrease all cause mortality.

Diabetic cardiac autonomic neuropathy (DCAN) is a common and serious complication of diabetes mellitus (DM), is manifested by nerve fiber injury in the sympathetic and parasympathetic nerve of the autonomic nervous system, and causes hypertension, cardiac arrhythmias, silent myocardial infarction, and sudden death. Our previous study observed that P2X3 receptor in superior cervical ganglia in rat was associated with sympathetic neuropathy caused by myocardial ischemia. However, whether the P2X3 receptor is involved in the diabetic cardiac autonomic neuropathy and the underlying mechanisms remain unclear. The aim of this research was explored the effect of P2X3 short hairpin RNA (shRNA) on information transmission of sympathetic nerve induced by DCAN. Sprague-Dawley (SD) male rats were randomly divided into four groups: Control, DM, DM treated with P2X3 shRNA and DM treated with scramble shRNA. Blood pressure, heart rate and heart rate variability were measured in each group. The expression of P2X3 in stellate ganglion (SG) was detected by immunohistochemistry, western blotting and QPCR. Results showed that P2X3 shRNA alleviated blood pressure and heart rate, improved heart rate variability, decreased the up-regulated expression levels of P2X3, interleukin-1beta and tumor necrosis factor alpha in stellate ganglion (SG) of diabetic rats. P2X3 shRNA also reduced the incremental concentration of serum epinephrine and the phosphorylation level of extracellular regulated protein kinases1/2 in diabetic rats. These results indicated that P2X3 shRNA could decrease sympathetic activity via inhibiting P2X3 receptor in the SG to alleviate DCAN.

Utilising time-stamped lifelogging images collected from a sample of 30 older adults in three neighbourhoods of Singapore, this study explores older adults’ daily walking travel patterns and their associations with neighbourhood-level built environment features. The visual lifelogging method uses a wearable camera to automatically record individual activities from a “first-person” perspective and capture novel information of environmental features encountered by individuals in real time. The findings reveal that older participants in the study areas, on average, take about 4 walking trips per day with an average trip length of about 15 minutes. Neighbourhood facilities including public open spaces, senior activity centres, and food courts are the most visited destinations while urban design features such as covered walkways, tree shades and street furniture are frequently encountered during walking trips.

Gentamicin mycelial residues (GMRs) are microbial fermentation residues of the pharmaceutical industry. In this study, anaerobic digestion of GMRs in combination with microwave-alkaline pretreatment (MAPT) was first employed to enhance methane production and the efficiency of gentamicin degradation. The anaerobic digestion batch tests were conducted to optimize the MAPT conditions, and semi-continuous tests of three-month duration were carried out to investigate the anaerobic digestion performance and fate of gentamicin. The results indicated that the GMRs flocs were substantially disintegrated after MAPT, and the average particle size was significantly related to methane production (p 12) suggested that the excessive alkali dosage in the pretreatment process adversely affected the anaerobic digestion performance due to the solubilization or generation of the refractory compounds (e.g. melanoidin). An increase of 58.05% in methane production (323.33 ± 11.88 mL gVS−1) was accomplished by MAPT in the sable running stage of the semi-continuous stirring tank reactor. The analysis of gentamicin mass balance in anaerobic digestion process demonstrated that the degradation was a preponderant mechanism for gentamicin removal. Simultaneously, MAPT facilitated the release of gentamicin trapped in flocs, thus, effectively improving the average degradation efficiency of gentamicin in anaerobic digestion process (degradation efficiency: 97.70 ± 0.63%).

Increasing CO2 emissions from the transport sector have raised substantial concerns among researchers and policy makers. This research examines the impact of the built environment on individual transport emissions through two mediate variables, vehicle usage and vehicle type choice, within a structural equation modelling (SEM) framework. We find that new-urbanism-type built environment characteristics, including high density, mixed land use, good connectivity, and easy access to public transport systems help reduce transport CO2 emissions. Such mitigating effect is achieved largely through the reduced vehicle miles travelled (VMT) and is enhanced slightly by the more efficient vehicles owned by individuals living in denser and more diverse neighborhoods, all else being equal. Our research findings provide some new evidence that supports land use policies as an effective strategy to reduce transport CO2 emissions.

Alkaline-thermal (AT) pretreatment is an economical and efficient pretreatment method to improve anaerobic biodegradability of biowaste. This study investigated the effect of AT pretreatment of spectinomycin mycelial residues (SMRs) for promoting anaerobic biodegradability along with the reduction of antibiotic resistance genes (ARGs), and thus obtained the optimal conditions of AT pretreatment. Biomethane potential (BMP) test was conducted to evaluate the anaerobic biodegradability of untreated and pretreated SMRs, and the fate of ARGs was tracked by quantitative polymerase chain reaction. Results showed that the modified Gompertz model fitted the results of BMP tests satisfactorily. Furthermore, AT pretreatment promoted BMP (B0) and reduced lag phase (λ) effectively. These were attributed to the solubilization of SMRs. The analyses of the changes in dissolved organic matter indicated that AT pretreatment could facilitate the solubilization of both biodegradable (e.g. protein) and recalcitrant matter (e.g. humic-like, analyzing by EEMs-PARAFAC), which had a significant corresponding positive (Person correlation, p

Introduction An increasing body of evidence suggests that regular physical activity can have important beneficial effects on individuals’ health into later years. This research investigated the inter-relationships between neighbourhood built environment, physical activity and three physical health outcomes among older adults in Singapore. Methods Drawing on 2018 data from 810 community-dwelling older adults in Singapore, a simultaneous equation approach was utilised to disentangle the complex interactions among built environment (both objective and self-reported measurements), physical activity and physical health (i.e., body mass index, functional capability and presence or absence of ‘three high’ chronic diseases) while controlling for other confounding factors, including socio-demographics and health behaviour. Results The accessibility to destinations (e.g., parks, open spaces, playgrounds) and other walkability features (e.g., neighbourhood safety, covered footpath) could promote transportation or recreational outdoor physical activity and therefore, health among older residents in Singapore. Interestingly, built environment characteristics related differently to physical activity undertaken for transportation and recreational purposes. There was a bi-directional relationship between an older adult's functional status and transport-related physical activity. There was also evidence that the connection between number of chronic diseases and recreational physical activity was reciprocal. Conclusion Insights into the built environment-physical activity-physical health relationships highlight the importance of supportive built environment in the process of health enhancement for older people.