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Singapore is known for differentiating highly skilled and low-skilled migrants by regulating their social rights, employment, and pathways to permanent residency and citizenship. Since 2009, the city-state has made further differentiation between highly skilled migrants and natives, that is, native-born citizens. Existing studies on migrant differentiation mostly adopt a state-centric perspective. We argue that differentiation is also driven by forces from below. We introduce the concept of differential fairness to capture natives' justification for differentiation between themselves and migrants, particularly the highly skilled. Drawing on survey data and in-depth interviews with natives and Chinese and Indian migrants, we show that natives demand for preferential policies to protect their interests. We further reveal that the measures of differentiation have created an integration dilemma, in which natives and migrants hold divergent views on fairness and expectations of migrant integration. [ABSTRACT FROM AUTHOR]

• Interactions between non-migrants and migrants inflect their ageing experiences. • The spatial attributes of shared spaces can deter or foster intercultural relations. • Micro-publics reveal whether meaningful co-presence exists in shared space. • Ageing-in-place needs to be analysed alongside ageing-across-borders. • Qualitative GIS methods provide a fuller perspective of older adults' life-worlds. While there has been considerable academic interest in the topics of encounters and conviviality, including within the migration literature, little is known about how non-migrant and migrant older adults interact with one another in shared spaces, forming micro-publics that inflect the experiences of ageing for both groups. Using Qualitative Geographic Information Science (qualitative GIS), this paper identifies three types of spaces shared by non-migrant and migrant older adults from Singapore and the People's Republic of China respectively. The first type of shared space is characterised by asynchronicity in that, despite co-located activities, intercultural interactions are less likely to be fostered between non-migrants and migrants. The second type of shared space features informal, spontaneous encounters that develop into more regular forms of interaction with 'otherness', but active negotiation of social difference could be limited. The third type of shared space is marked by formal, organised activities where non-migrants and migrants work towards a common goal, prompting productive negotiations with difference. Through juxtaposing these three types of shared spaces, we argue for the importance of drawing out how spatial attributes can deter or foster varying degrees of negotiations with difference, while acknowledging that the fluidity of such processes depend on the users and social contexts too. We also suggest that notions of ageing-in-place need to be analysed alongside ageing-across-borders, giving attention to how migration impacts ageing in later life—both for migrants who are adapting to life abroad temporarily as well as non-migrants who may experience "transnationalism by proxy". (247 words; max 250 words) [ABSTRACT FROM AUTHOR]

• Application of cool surface on street canyon reduces up to 30% sensible heat. • Combined effect of cool roof, wall and cool road can reduce canyon air temperature. • Cool Canyon provides improved thermal comfort to pedestrians in UTCI. • View factor with the cool surface plays an important role on pedestrian comfort. The Urban Heat Island (UHI) effect has been a cause of concern on human-induced impacts to urban climate. Construction materials absorb incoming solar radiation, causing additional sensible heat release to the urban environment resulting in urban air temperature changes. It has been proposed that covering the built-up surfaces such as building roofs and walls as well as road pavements, with cool surfaces which reflect most of the incoming solar radiation, could reduce heat absorption by construction materials and the subsequent heat release to urban environment. This paper, reports an experimental study of cool coating in a full-scale site setting located in Singapore during the summer months of tropical climate. The experimental site consists of four parallel industrial buildings forming two similar side-by-side street canyons. One of the canyons ('Cool Canyon') was cool coated on the roofs, walls and the road pavement whereas the other canyons remained as it was ('Conventional Canyon') as control. Air temperature, surface temperature, sensible and latent heat fluxes in the two canyons were monitored for analysis of thermal exchanges between the build-up surfaces and the canyon micro-environment. The Cool Canyon had up to 30% reduction in sensible heat release from the built-up surfaces which resulted in the air temperature in Cool Canyon being cooler than that in the Conventional Canyon by up to 2°C around 16:00 h. An analysis of pedestrian thermal comfort in the two canyons was also conducted using Universal Thermal Climate Index (UTCI). When compared to the Conventional Canyon, the Cool Canyon provides improved thermal comfort to pedestrians with up to 1.5°C reduction in UTCI. The paper also presents a critical analysis on thermal comfort due to the cool road in the middle of the street canyon. [ABSTRACT FROM AUTHOR]

Pb is a trace metal that tracks anthropogenic pollution in natural environments. Despite recent leaded petrol phase out around Southeast Asia, the region's growth has resulted in continued exposure of Pb from a variety of sources. In this study, sources of Pb into Singapore, a highly urbanised city-state situated in the central axis of Southeast Asia, are investigated using isotopic ratios and concentrations. We compiled data from our previous analyses of aerosols, incineration fly ash and sediments, with new data from analyses of soil from gas stations, water from runoff and round-island coastal seawater to obtain a spatio-temporal overview of sources of Pb into the Singapore environment. Using 206 Pb/ 207 Pb ratio, we identified three main Pb source origins: natural Pb (1.215 ± 0.001), historic/remnant leaded petrol (1.123 ± 0.013), and present-day industrial and incinerated waste (1.148 ± 0.005). Deep reservoir sediments bore larger traces of Pb from leaded petrol, but present-day runoff waters and coastal seawater were a mix of industrial and natural sources with somewhat variable concentrations. We found temporal variability in Pb isotopic ratio in aerosols indicating alternating transboundary Pb sources to Singapore that correspond to seasonal changes in monsoon winds. By contrast, seasonal monsoon circulation did not significantly influence isotopic ratios of coastal seawater Pb. Instead, seawater Pb was driven more by location differences, suggesting stronger local-scale drivers of Pb such as point sources, water flushing, and isotope exchange. The combination of multiple historic and current sources of Pb shown in this study highlights the need for continued monitoring of Pb in Southeast Asia, especially in light of emerging industries and potential large sources of Pb such as coal combustion. [ABSTRACT FROM AUTHOR]

Particles released from biomass burning can contribute to severe air pollution. We monitored indoor and outdoor particles in a mechanically ventilated and air-conditioned building during and after the 2013 haze event in Singapore. Continuous monitoring of time-and size-resolved particles in the diameter range 0.01–10 μm was conducted for two weeks in each sampling campaign. During the haze event, the averaged size-resolved outdoor particle volume concentrations (d V /d(log D p )) for diameters larger than 0.3 μm were considerably higher than those during the post-haze days (9–185 μm 3 cm −3 versus 1–35 μm 3 cm −3 ). However, the average number concentration of particles with diameters in the range 10–200 nm was substantially lower on the hazy days than on the post-haze days (11,400 to 14,300 particles cm −3 for hazy days, versus an average of 23,700 particles cm −3 on post-haze days). The building mechanical ventilation system, equipped with MERV 7 filters, attenuated the penetration and persistence of outdoor particles into the monitored building. Indoor particle concentrations, in the diameter ranges 0.3–1.0 μm and 1.0–2.5 μm, closely tracked the corresponding patterns of outdoor particle concentrations. For particles in the size range 0.01–1.0 μm, the size-resolved mean indoor/outdoor (I/O) ratios were in the range 0.12–0.65 with the highest mean I/O ratio at 0.3 μm (0.59 in AC on mode and 0.64 in AC off mode). The air conditioning and mechanical ventilation system with MERV 7 filters provided low single-pass removal efficiency (less than ∼ 30%) for particles with diameters of 0.01–1.0 μm. During the haze, for particles larger than ∼0.2 μm, lower I/O ratios and higher removal efficiencies occurred with the air conditioning operating as compared to with mechanical ventilation only. This observation suggests the possibility of particle loss to air conditioning system surfaces, possibly enhanced by thermophoretic or diffusiophoretic effects. [ABSTRACT FROM AUTHOR]

Short term power load forecasting plays an important role in the management and development of power systems with a focus on the reduction in power wastes and economic losses. In this paper, we construct a novel, short-term power load forecasting method by improving the bidirectional long short-term memory (Bi-LSTM) model with Extreme Gradient Boosting (XGBoost) and Attention mechanism. Our model differs from existing methods in the following three aspects. First, we use the weighted grey relational projection algorithm to distinguish the holidays and non-holidays in the data preprocessing. Secondly, we add the Attention mechanism to the Bi-LSTM model to improve the validity and accuracy of prediction. Thirdly, XGBoost is a newly-developed, well-performing prediction model, which is used together with the Attention mechanism to optimize the Bi-LSTM model. Therefore, we develop a novel, combined power load prediction model "Attention-Bi-LSTM + XGBoost" with the weight determination theory-error reciprocal method. Using two power market datasets, we evaluate our prediction method by comparing it with two benchmark models and four other models. With our prediction method, the MAPE, MAE, and RMSE for the Singapore's power market are 0.387, 43.206, and 54.357, respectively; and those for the Norway's power market are 0.682, 96.278, and 125.343, respectively. The test results are smaller than the results for six other models. This indicates that our prediction method outperforms the LSTM, Bi-LSTM, Attention-RNN, Attention-LSTM, Attention-Bi-LSTM, and XGBoost in effectiveness, accuracy, and practicability. [ABSTRACT FROM AUTHOR]

The 2013 haze was the most serious air pollution event in Singapore's history. Individual exposures to particulate matter differ (a) according to time patterns of behaviour and (b) with the varying degrees of protection provided by buildings against penetration and persistence of outdoor particles. Utilizing real-time personal monitoring, we evaluated exposures to size-segregated fine particulate matter (PM) of five office workers for six days during the latter portion of the 2013 haze event. The outdoor volume concentrations of particulate matter (0.3–2.5 μm diameter) during moderate and light haze days were in the ranges 15–21 μm 3 /cm 3 and 7–10 μm 3 /cm 3 , respectively. More than 80% of total daily exposures occurred indoors in workplaces and residences. The daily-integrated personal exposures for the five subjects during the moderate and light haze days were 140–454 (μm 3 /cm 3 )-h and 66–239 (μm 3 /cm 3 )-h, respectively. Exposure factors for the five participants, quantifying the extent of exposure reduction associated with being indoors, had daily average values ranging from 0.32 to 0.75. The results of this study contribute toward deeper understanding the degree of protection provided by the buildings from pollution of outdoor origin. The work also contributes knowledge regarding personal exposure to particulate matter during air pollution episodes, especially for tropical climates. [ABSTRACT FROM AUTHOR]

Anthropogenic lead (Pb) has been the overwhelming Pb source to the global ocean, primarily contributed from Pb gasoline and industrial emissions. However, since Pb gasoline has been phased out globally, questions about whether there was a decrease in seawater Pb concentration, or if there are other sources taking over remains unclear in Southeast Asia. Here, combining Pb concentrations in seawater from Singapore Strait in 2010–2017; trap sediment in 2018–2019; and the previously published coral reconstruction covering 1975–2010; we found that the seawater Pb concentration in Singapore Strait over past decades followed the regional gasoline emissions, and no additional major source had contributed the Pb in the seawater since ~2010. The present-day Pb in Singapore Straits' water mainly follows the monsoonal current reversals, with variable degrees of scavenging that peak in inter-monsoon season. Minor Pb sources still contribute to some local-scale variabilities, despite a decadal-scale decreasing trend of Pb in seawater. • Seawater samples were collected from Singapore Straits between 2010 and 2017. • Monthly trap sediments were collected in 2018–2019 for seasonal scavenging dynamics. • Pb concentrations in seawater spliced with 30-year-long coral skeletal Pb/Ca records • Lowered Pb concentrations in seawater since regional phase out of leaded gasoline • Both hydrodynamics and scavenging influence the seasonal variability of Pb in seawater. [ABSTRACT FROM AUTHOR]

Maritime Knowledge Clusters are known to facilitate regional economic growth. Nevertheless, few studies have been conducted to examine their impact on maritime firms' performance. Drawing on organizational learning theory, this study investigates the effect of maritime knowledge clusters on the constituent maritime firms' performance. A conceptual model was proposed and examined using survey data collected from shipping professionals in Singapore. Confirmatory factor analysis and structural equation modelling were employed as the data analysis approach. The results show that the positive relationship between maritime knowledge clusters and maritime firms' performance is fully mediated by the firms' social capital and absorptive capacity in a sequential manner. This indicates that maritime firms should focus on strengthening not only their social capital but also absorptive capacity so as to fully enjoy the benefits brought about by maritime knowledge clusters. In addition, regulators should endeavor to develop global linkage, global systemic mechanisms and local knowledge clusters to facilitate organizational learning of the constituent maritime firms. • This study investigates the effect of maritime knowledge clusters on the constituent maritime firms' performance. • A conceptual model was proposed and examined using survey data collected from 203 shipping professionals in Singapore. • The positive relationship between maritime knowledge clusters and maritime firms' performance is fully mediated. • Maritime firms shall focus on strengthening not only their social capital but also absorptive capacity so as to fully enjoy the benefits brought about by maritime knowledge clusters. [ABSTRACT FROM AUTHOR]

Maritime Knowledge Clusters (MKCs) are the advanced stage in the evolution path of maritime clusters. Earlier literature however mostly focused on either the characteristics i.e. critical success factors or competitiveness of maritime clusters in general and not on the components of MKCs, their interrelationships, and impact on the performance of constituent firms. This study proposes and tests a conceptual model of Maritime Knowledge Clusters (MKC) and the relations between their components, making use of survey data from 203 shipping professionals located in Singapore. Three theoretical perspectives, namely, relational view, knowledge-based view and resource-based view, have been employed. The results demonstrate that MKCs are substantiated by three critical components, in which the local knowledge cluster can develop global systemic mechanisms, thus further strengthening global linkages. Policy makers must endeavor to create a conducive local cluster environment with maritime firms being located in geographical proximity, and having local networks, knowledge base, and knowledge flows. They form the fundamental foundation for the growth of MKCs. Besides, maritime firms shall optimize the MKC's local knowledge cluster to facilitate their global expansion, which will in turn boost the internationalization of the MKC. • This study conceptualizes the Maritime Knowledge Clusters (MKCs) and empirically examines the interrelationships between its components. • Structural equation modeling was employed to test the conceptual model. • MKCs are substantiated by three critical components: local knowledge cluster, global systemic mechanisms, and global linkages. • Policymakers should create a conducive local cluster environment with maritime firms being located in geographical proximity, having local networks, knowledge base, and knowledge flows. [ABSTRACT FROM AUTHOR]

Blockchain has the potential to improve the efficiency and transparency of maritime businesses and operations. Nevertheless, few studies have been conducted to identify the key challenges and critical success factors (CSFs) of blockchain implementation in the maritime industry. A case study approach based on Singapore's maritime industry is adopted. Four interviews are conducted to establish the face validity of the survey questionnaire before data are collected from 30 maritime professionals from Singapore's maritime industry. In addition to analytic hierarchical process (AHP), a fishbone diagram and PESTEL analysis are also adopted to organize and discuss the results. The results show that there are six key challenges and six CSFs for blockchain implementation. Using a fishbone diagram, the six identified challenges along with 13 personal concerns are categorized into five dimensions related to people, methods, organization, external environment, and technology. The CSFs are sufficient capital, staff training, ease of local legislation, support from the shipping community, support from the senior management, and professional consultation and assistance. This study implicates marine policy formulation in relation to subsidies and investments, blockchain talent and knowledge acquisition, and workforce training and education to accelerate blockchain implementation in the maritime industry. • Analyze challenges and critical success factors (CSFs) of blockchain implementation. • Challenges concern people, methods, organization, external environment, and technology. • CSFs are capital, training, legislation, shipping community, and senior management support. [ABSTRACT FROM AUTHOR]

Background: Epidemiologic studies suggest that declining estrogen levels in menopause may play an important role in the pathogenesis of dementia and contribute to increased risk of cognitive impairment in women. Most previous studies have been conducted in Western populations to investigate the relationship of the length of reproductive periods and use of hormone-replacement therapy with risk of cognitive function and dementia, but the findings are inconclusive. Relevant evidence among Asian populations is limited.Objectives: To evaluate the association between reproductive and hormonal factors and the risk of cognitive impairment in Chinese women with natural menopause.Study Design: The Singapore Chinese Health Study is a population-based study that recruited participants aged 45-74 years between 1993 and 1998, and the current study included 8222 women from this cohort who had natural menopause, complete data on reproductive factors and hormonal therapies at baseline (1993-1998), follow-up 1 (1999-2004) and follow-up 2 interviews (2006-2010), and cognitive function evaluated at ages 61-96 years using the Singapore Modified Mini-Mental State Examination during the follow-up 3 visits (2014-2016). Multivariable logistic regression models were used to estimate odds ratios and 95% confidence intervals for the risk of cognitive impairment.Results: Compared with women with menopause at 50-54 years of age, the odds ratios (95% confidence interval) were 1.67 (1.32-2.11), 1.24 (1.08-1.44), and 1.06 (0.87- 1.29) for women who experienced menopause before 45 years, at 45-49 years of age, and after 54 years, respectively. Compared with women with 35-39 reproductive years from menarche to menopause, the odds ratios (95% confidence interval) were 1.28 (1.11-1.48) for women with <35 reproductive years. Furthermore, compared with women who had 1-2 children, the odds ratios (95% confidence interval) were 1.27 (1.04-1.55) for women who had more than 5 children, and the risk increased significantly by 5% per child birth (odds ratio, 1.05; 95% confidence interval, 1.01-1.09). Compared with those who had never used oral contraceptives, women with short-term use (≤5 years) of oral contraceptives had 26% lower odds of having cognitive impairment (odds ratio, 0.74; 95% confidence interval, 0.63-0.87), whereas the association was not statistically significant for those used for more than 5 years (odds ratio, 0.87; 95% confidence interval, 0.68-1.13). Women who used hormone-replacement therapy had a 39% lower odd of getting cognitive impairment compared with nonusers (odds ratio, 0.61; 95% confidence interval, 0.46-0.80).Conclusion: Our data suggest that shorter reproductive years and greater parity were associated with a greater risk of cognitive impairment in late life, whereas the use of oral contraceptives and hormone-replacement therapy was associated with decreased risk. As the population ages, understanding how these factors affect late-life cognitive function in women may help health professionals develop preventive measures targeting lifetime estrogen exposure from endogenous or exogenous sources. [ABSTRACT FROM AUTHOR]

Bats are important reservoirs and vectors in the transmission of emerging infectious diseases. Many highly pathogenic viruses such as SARS-CoV and rabies-related lyssaviruses have crossed species barriers to infect humans and other animals. In this study we monitored the major roost sites of bats in Singapore, and performed surveillance for zoonotic pathogens in these bats. Screening of guano samples collected during the survey uncovered a bat coronavirus ( Betacoronavirus ) in Cynopterus brachyotis , commonly known as the lesser dog-faced fruit bat. Using a capture-enrichment sequencing platform, the full-length genome of the bat CoV was sequenced and found to be closely related to the bat coronavirus HKU9 species found in Leschenault's rousette discovered in the Guangdong and Yunnan provinces.

Age-related macular degeneration (AMD) is a leading cause of irreversible central blindness among the elderly worldwide. We use exome sequencing to analyse nonsynonymous single-nucleotide variants (SNVs) across the whole genome of 216 neovascular AMD cases and 1,553 controls. As a follow-up validation, we evaluate 3,772 neovascular AMD cases and 6,942 controls from five independent cohorts in the East Asian population. Here we show strong evidence of an association at a novel, missense SNV, rs7739323, which is located in the ubiquitin protein ligase E3D (UBE3D) gene (Pmeta=1.46 × 10(-9), odds ratio (OR)=0.74, 95% confidence interval (CI): 0.63-0.88). Furthermore, ablation of the UBE3D protein lead to an abnormal amount of pigment granules deposited in retinal pigment epithelium microvilli area and an abnormal response on electroretinography (ERG) in UBE3D(+/-) heterozygous mice. Our findings indicate that the ubiquitin-proteasome system may play a role in the pathogenesis of neovascular AMD.