Search

Climatic elements such as temperature and rainfall provide great and unquantifiable benefits to human health. However, rapid urban sprawl has the tendency to undermine these health consequences. The relationship between urban sprawl and microclimate in the Ga East Municipality has been assessed to present the extent of sprawl that inhibit temperature and rainfall in recent times. Methodologically, satellite imagery and meteorological data (minimum and maximum temperature and rainfall) from 1990 to 2020 were used. The results indicate that rapid urban sprawl in recent times has significantly undermined the local climate through land use and land cover changes. There was strong statistical relationships between temperature and built-up areas (p0.05), grass/shrub cover (p0.04) and all vegetation cover (p0.03). There was also strong statistical relationship between rainfall and built-up areas (p0.03), grass/shrub cover (p0.04) and all vegetation (p0.02). Thus, expansion in built up areas and reduced grass/shrub cover led to increases in temperature, rainfall and surface water run off while reduction in all vegetation led to increase in both temperature and rainfall. These changes in climate brought about by urban sprawl will affect crop production, increase cataclysmic floods as well as growth of some harmful insects. There is the need for the amalgamation of urban growth and climate change into spatial planning through an all-embracing approach.

Dimensions of risks and impacts of occupational heat stress due to climate change on workers' health and safety, productivity, and social well-being are significantly deleterious. Aside from empirical evidence, no systematic review exists for policy development and decision making in managing occupation heat stress impacts and adaptation strategies of workers. This study sought to synthesise evidence on the social impacts of occupational heat stress and adaptation strategies of workers. From a review of existing literature, eight categories were obtained from 25 studies and grouped into three syntheses: (1) awareness of occupational heat stress, (2) social impacts of occupational heat stress and (3) workers' adaptation to occupational heat stress due to changing climate. Awareness of occupational heat stress among workers varied and their social impacts were related to workers' health and safety, productivity and social well-being. Sustainable adaptation to occupation heat stress due to climate change hinges on financial resource availability. Adequate investment and research are required to develop and implement policies to combat the threat of rising temperature and climate change to enhance workers' adaptive capacity, boost resilience and foster sustainable development.

Current climate trends of extreme temperature and humidity during summer present a public health dilemma in Zimbabwe and other developing countries. National and local governments have defined roles to protect the health of populations under their jurisdictions as stipulated in relevant policies. The involvement of public health practitioners in policy development and management of heat-related illnesses is vital for the protection of the public, particularly vulnerable groups. The current role of health providers in developing countries regarding climate change impacts on health is considered suboptimal. Focus group interviews with public health practitioners and policy makers in the city of Bulawayo in Zimbabwe showed that officials lacked knowledge and awareness regarding heat-related impacts on health, particularly in relation to differences in individual susceptibility and currently employed heat adaptation and coping mechanisms.

Heat exposure studies over the last decade have shown little attention in assessing and reporting the psychometric properties of the various scales used to measure impacts of occupational heat stress on workers. A descriptive cross-sectional survey including 320 small- and large-scale mining workers was employed to assess the construct validity of the social impacts of occupational heat stress scale (SIOHSS) in the Western Region of Ghana in 2017. A confirmatory factor analysis (CFA) and invariance analysis were carried out using AMOS version 25 and statistical product and service solutions (SPSS) version 26 to examine the model fit and establish consistency correspondingly across multiple groups (gender, age, working hours, type of mining and workplace setting). Empirically, our results depicted that effects on health and safety, behavioural, productivity and social well-being were each found to be reliable, with Cronbach's α of 0.722, 0.807, 0.852 and 0.900 respectively. Though there were issues of insufficient discriminant validity as some average variance extract (AVE) were smaller than the corresponding maximum shared variance (MSV), the CFA showed good model fit indices (CFI = 0.856, GFI = 0.890, TLI = 0.863, SRMR = 0.08, RMSEA = 0.08). Also, the model was variant for all constrained aspects of the structural model indicating a requirement for an adaptation of the instrument across groups. The good to moderate internal consistency and construct validity of the SIOHSS is adequate evidence for the confidence required for its reliability and accuracy in measuring the social impacts of occupational heat stress on workers.

Lumber size control is an essential element in maximising yield and productivity because a small reduction in rough green target size could lead to substantial savings in wood fibre. One of the key components of rough green target size is sawing variation. In this study, the optimum side clearance of band saw teeth leading to a minimum saw teeth deflection and minimum lumber thickness variation of stellite-tipped and swage-set saws when processing Triplochiton scleroxylon a tropical hardwood were examined. It was observed that the accuracy of kerf width was best with stellite-tipped saws. However, Analysis of variance (ANOVA) at 5% level of significance indicates that there was no significant difference between the accuracy of kerf width of stellite-tipped saws and swage-set saws. It also was observed that at 5% level of significance, the mean kerf width of stellite-tipped saws, which was 4.2 mm, was significantly greater than the mean kerf width of 3.06 mm of the swage-set saws. Sawing variation as indicated by standard deviation of lumber thickness was best for the swage-set saws. A quadratic relationship between sawing variation and side clearance of stellite-tipped saws was established. As the side clearance of the saw increases, the sawing variation decreases until it reaches a minimum value and thereafter, further increase in side clearance of the saw teeth results in an increase in sawing variation. It was observed that an optimum side clearance of 0.69 mm under a saw blade thickness of 1.3 mm was required to produce on the average, a minimum value of 0.42 mm for within-board standard deviation, and 0.59 mm for the total standard deviation. An error margin of less than 1% was achieved when the experimental results for the optimum side clearance was compared with a theoretical assertion.