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Semi-Flexible Asphalt (SFA) mixture is a wearing course in which Open-Graded Asphalt (OGA) mixes having air voids of 20–35% are grouted with cement mortar. The grout consists of cement, sand, superplasticizer, and water. In the present work, an effort was made to assess the effect of the Sand-Cement (S/C) ratio in determining the optimal grout proportions. Taguchi technique combined with Grey Relational Analysis was used to obtain the optimal grout proportion. The optimum grout was found to be the mixture prepared with an S/C ratio of 0.6, a water-to-cement (W/C) ratio of 0.40, and a polycarboxylic ether-based superplasticizer (SP) content of 0.75% by weight of cement. The SP content was the most influencing factor, while the S/C ratio was the second most influencing factor. To investigate the effect of aggregate gradation and bitumen type on the mechanical properties of SFA mixtures, a new aggregate gradation with neat and modified bitumen was used to prepare OGA mixtures and later grouted with optimal grout proportion. The Marshall Stability, compressive strength, Indirect Tensile Strength, Cantabro loss, fatigue resistance, moisture and Oil spillage resistance tests were conducted. The results showed that the SFA mixtures prepared with polymer-modified bitumen and the new aggregate gradation have better mechanical properties, implying the significance of bitumen type and aggregate gradation.

Abstract Wind tunnel experiments were performed to evaluate the power coefficients of three vertical axis wind turbines (VAWTs), namely, (a) conventional VAWT (two‐bladed troposkien shape), (b) novel 50% shifted troposkien shape‐vertical axis wind turbine (50% STS‐VAWT), and (c) novel 100% STS‐VAWT. All turbines had the same height, swept area, and NACA0015 airfoil with the same chord length. During the power coefficient measurements for each one of the turbines, the wind tunnel velocity was varied while the turbine rotation was kept constant through rheostatic load adjustment. Two different turbine rotations were used (600 rpm and 700 rpm). The resulting tip speed ratios (TSRs) ranged from approximately 2 to 6 in the current investigation. Both the power coefficients and the tip speed ratios were corrected against wind tunnel blockage effects. The 50% STS‐VAWT model showed an overall better aerodynamic performance (both corrected and uncorrected power coefficients) when compared against the other two configurations, likely due to a combination of (a) power generation increased due to blade‐wake interaction (BWI) reductions and (b) power generation capacity related to the blade length of each turbine.

Abstract The aerodynamic performance of three different configurations of vertical axis wind turbines (VAWT), namely: (a) conventional Darrieus troposkein VAWT (based on turbines designed by Sandia National Laboratories), (b) novel 50% STS‐VAWT (50% shifted‐troposkein‐shaped STS‐VAWT), and (c) novel 100% STS‐VAWT were investigated numerically. An in‐house code, which combined the blade element theory (BET) and the vortex filament method (VFM), was used. The main purpose of this work was to develop an aerodynamic code to predict the performance of conventional VAWT as well as assess the novel 50% and 100% STS‐VAWT configurations. Simulation results (power coefficients) were verified and then validated against experimental data available from the literature (2‐, 5‐, and 17‐m conventional troposkein VAWT measured by Sandia National Laboratories). Additional numerical results showed that the 50% STS‐VAWT outperformed both the conventional VAWT and the 100% STS‐VAWT by up to 14% (peak power), within the range of rotation and turbine sizes that were investigated in the present work.

Introduction: Natural hazards are damaging environmental events, such as fires, droughts and floods, which have negative impacts on human lives, livelihoods and health. Natural hazards are increasing in intensity and severity, and may potentially have harmful effects on the health and development of children who experience them. There are few syntheses of the evidence about the effects of natural hazards on the early development of children aged from birth to 5 years old. The aim of this systematic review and meta-analysis is to determine the impact of natural hazards on the cognitive, motor, language, social and emotional development of children from birth to 5 years old., Methods and Analysis: Comprehensive searches will be conducted in five bibliographic databases: Ovid MEDLINE, Ovid PsycInfo, CINAHL Plus, Scopus and Ovid EMBASE, using predefined search terms to identify the relevant studies. The review will follow the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Eligible studies will be included if they report on the association between exposure to natural hazards and at least one indicator of early childhood development (ECD). Extracted data will include: main study findings, characteristics of the study design, measures of natural hazards and ECD indicators. Observational studies with cross-sectional, case-control, prospective or retrospective cohort designs will be included in this review. Case descriptions and qualitative studies will be excluded. Study quality will be assessed using the Joanna Brigg's Institute critical appraisal tools. We will conduct a meta-analysis if the reviewed studies are sufficiently homogeneous according to research design, exposure, participants and outcome measures. The meta-analysis will include subgroup analyses (eg, length of exposure to natural hazard, type of natural hazard, ECD indicator)., Ethics and Dissemination: The findings will be disseminated through a peer-review publication, policy brief, technical report and report published on institutional stakeholder websites., Prospero Registration Number: CRD42022331621., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Forced migration can lead to loss of social support and increased vulnerability to psychological distress of displaced individuals. The aims were to ascertain the associations of sociodemographic characteristics and social support received by resettled adult humanitarian migrants in Australia; determine the relationship between social support and mental health at different intervals following humanitarian migration; and examine the modification effects of gender, age and migration pathway on that relationship., Methods: A secondary analysis was conducted of data generated in Waves One (three to six months after resettlement), Three (three years after resettlement) and Five (five years after resettlement) of the Building a New Life in Australia prospective cohort study. The association between sociodemographic characteristics and mental health were examined at each timepoint using a multivariate regression model. Exploratory factor analysis was used to develop a two-factor social support scale (emotional/instrumental and informational support) from a larger set of items collected in the BNLA. Psychological distress was measured by the Kessler-6 scale. Path analysis was used to analyse the relationships between social support and psychological distress among the three time points considering socio-demographic characteristics simultaneously., Results: A total of 2264 participants were included in the analyses. Age, gender, birth region, migration pathway, education level and English proficiency were significantly associated with both social support types. Main source of income was only significantly associated with informational support. Remoteness area was only significantly associated with emotional/instrumental support. As emotional/instrumental support increased by one standard deviation (SD) at Wave One, psychological distress at Wave Three decreased by 0.34 score [95% CI (- 0.61; - 0.08)]. As informational support at Wave Three increased by one SD, psychological distress at Wave Five decreased by 0.35 score [95% CI (- 0.69; - 0.01)]. The relationships between social support and psychological distress varied between genders, age groups and migration pathways., Conclusion: Findings demonstrate the importance of emotional/instrumental support and informational support for the medium and long-term mental health of humanitarian migrants. This study also highlights the important of extending current social support provisions and tailoring programs to enhance support received by humanitarian migrant subgroups years after resettlement to improve mental health., (© 2022. The Author(s).)

Background: The World Health Organization recommends breastfeeding for at least two years (24 months or more) after birth. In Vietnam, 22% of women continue breastfeeding for at least two years. The aim of this study was to determine the sociodemographic and psychosocial characteristics of mother-baby dyads associated with breastfeeding for 24 months or more in a rural setting in Vietnam., Methods: A secondary analysis was conducted on existing data obtained from a prospective study in Ha Nam, Vietnam. Women were recruited when they were pregnant and were followed up until 36 months after giving birth. The data were collected between 2009 and 2011. The associations between sociodemographic and psychosocial characteristics and continued breastfeeding for 24 months or more were examined using a multivariable logistic regression model., Results: Overall, 363 women provided complete data which were included in the analyses. Among those, 20.9% breastfed for 24 months or more. Women who were 31 years old or older were more likely to breastfeed for 24 months or more than women who were 20 years old or younger (adjusted odds ratio, AOR, 9.54 [95% CI 2.25, 40.47]). Women who gave birth to girls were less likely to breastfeed for 24 or more months than women who had boys (AOR 0.44; 95% CI 0.25, 0.80)., Conclusions: This study provides evidence that may be useful for policy-makers to help improve breastfeeding practices for all children in Vietnam by targeting policy towards younger women and women with girls to promote continued breastfeeding for at least 24 months., (© 2021. The Author(s).)

Aims: The microbiome-derived metabolite trimethylamine-N-oxide (TMAO) has attracted major interest and controversy both as a diagnostic biomarker and therapeutic target in atherothrombosis., Methods and Results: Plasma TMAO increased in mice on 'unhealthy' high-choline diets and notably also on 'healthy' high-fibre diets. Interestingly, TMAO was found to be generated by direct oxidation in the gut in addition to oxidation by hepatic flavin-monooxygenases. Unexpectedly, two well-accepted mouse models of atherosclerosis, ApoE-/- and Ldlr-/- mice, which reflect the development of stable atherosclerosis, showed no association of TMAO with the extent of atherosclerosis. This finding was validated in the Framingham Heart Study showing no correlation between plasma TMAO and coronary artery calcium score or carotid intima-media thickness (IMT), as measures of atherosclerosis in human subjects. However, in the tandem-stenosis mouse model, which reflects plaque instability as typically seen in patients, TMAO levels correlated with several characteristics of plaque instability, such as markers of inflammation, platelet activation, and intraplaque haemorrhage., Conclusions: Dietary-induced changes in the microbiome, of both 'healthy' and 'unhealthy' diets, can cause an increase in the plasma level of TMAO. The gut itself is a site of significant oxidative production of TMAO. Most importantly, our findings reconcile contradictory data on TMAO. There was no direct association of plasma TMAO and the extent of atherosclerosis, both in mice and humans. However, using a mouse model of plaque instability we demonstrated an association of TMAO plasma levels with atherosclerotic plaque instability. The latter confirms TMAO as being a marker of cardiovascular risk., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)