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Due to the environmental issues caused by petroleum lubricants used in lubrication, the concept of creating various bio-lubricants requires research globally. Thus, this study aims to develop, characterize and test the base ficus carica oil (fig oil) for its ethylene vinyl acetate copolymer (EVA) and sodium dodecylbenzene sulfonate (SDBS) content.

The sample characterization was done using the Fourier transmission infrared spectrum, whereas the morphologies of the EVA, SDBS particles and lubricated surfaces were carried out under scanning electron microscope equipment. To ensure the homogeneity of the solution (base oil and additives), the formulations were subjected to the sonication process. The anti-friction and anti-wear properties of EVA and SDBS particles as lubricant additives were investigated using a ball on a flat high-frequency reciprocating rig tribo-tester.

According to the findings, the base oil’s anti-friction and anti-wear capabilities can be greatly enhanced by the additions. revealed that the best results were obtained when 1.2% EVA + 2% SDBS was applied for the examination of wear (597.8 µm) and friction coefficient (0.106). Commercial references were used, nevertheless, and the results were excellent. This is because the particles in the contact area during lubrication have strong solubility and quickly penetrate the contact zone. The lubricating mechanisms were explained by a tribological model of the EVA + SDBS and SDBS particles.

The coefficient of friction and wear reduction caused by the use of the additives will certainly enhance system performance and protect the machine components from excessive wear that could cause damage or failure.

The originality and uniqueness of this work are officially affirmed by the authors. The authors’ autonomous and original contribution to the development of sustainable lubrication is represented in this work. To the best of the authors’ knowledge, no other study has been published or made publicly available that duplicates the precise scope and goals of our research, and this conclusion is based on a thorough literature assessment.

The effects of dust exposure in buildings and its health and comfort consequences continue to concern occupants, particularly those who spend most of their time indoors. This study examines the influence of building opening characteristics on surface dust loading in indoor environments to determine the dust particles' impact on different opening configurations.

Indoor Harmattan dust surface loading data were collected from Maiduguri, Northeastern Nigeria, using model rooms with six different window configurations. A simple mathematical relationship was employed to assess surface dust loading characteristics in the model rooms. The study measured dust thrice between December and February for three days (72 h). The results were analyzed using descriptive statistics.

The results determined the highest average surface dust loading of 12.03 g/m2 in the room with awning windows at an indoor-to-outdoor (I/O) ratio of 0.7. In contrast, the experiment in the room with a closed window recorded the lowest average surface dust loading of 5.24 g/m2 at an I/O ratio of 0.30, which is infiltration. The outcomes further indicate that the average surface dust loading varies with the building opening type and position, as higher surface dust loadings were recorded in locations closer to the openings (doors and windows), reaffirming that the dominant source of the dust particles is outdoors. According to the study, dust incursion due to infiltration accounts for 30% of the outdoor surface loading.

Thus, Harmattan dust is a serious challenge to the health, productivity and hygiene of building occupants in the study area. The built-environment professionals must use the study's outcome to optimize building openings' designs (shape, size and form) for effective indoor dust control.

The purpose of this study is to assess the effects of financial management practices of small-scale building contractors on the technical performance of the contractors in the northern part of Nigeria with international best practices. Previous studies argued that the technical performance of small-scale building contractors in developing countries is poor because of insufficient cash to acquire strategic resources at the outset of a project. This continues to pose a challenge to the sustainable development of the construction industry, particularly in developing countries like Nigeria. There is, therefore, a need to identify, assess and compare the effects of financial practices of the contractors with technical performance best practices.

The technical performance of each contractor was evaluated using a five-point Likert scale. This is used to obtain the mean technical performance levels of the contractors. A questionnaire survey was administered to the professionals in the industry who were selected by using a proportionate stratified random sampling technique. The contractors’ performance was compared using ANOVA with post hoc, and the effects of contractors’ financial management practices were determined using multiple regression analysis.

The results of this study indicated that the contractors in Nigeria were average technical performers and there were large effects of financial management practices on the technical performance of contractors in building projects.

This study is limited to small-scale building contractors in northeast Nigeria. One of the implications of this study is that it provides the criteria for an evaluation of small-scale building contractors’ technical performance in Nigeria and other developing countries that faced similar problems.

The practical implications of this study are that it establishes the current level of contractors' technical performance and serves as an awareness of contractors' current financial practices.

This study created bases for self-evaluation of contractors’ technical performance and competition among small-scale contractors in Nigeria for the enhancement of productivity particularly in rural areas for national development.

This study emanated from the government reports and past studies in the area of performance management based on the persistence of poor technical performance of small-scale contractors in the construction industry.

This paper examined the current status of municipal solid waste management across Nigeria. The core aspects covered are generation, characterization, collection, scavenging, open dumping, disposal and environmental implications of poor solid waste management. The purpose of this paper is to present a comprehensive overview of the current state of municipal solid waste management in Nigeria.

This study was executed by a combination of an extensive literature search and field study. Solid waste generation rates for 31 Nigerian cities were obtained from literature. In addition, characteristics of municipal solid waste from 26 Nigerian cities were also obtained from literature. Other aspects such as characterization of solid waste obtained from final dumpsite and heavy metals accumulation in solid waste dumpsites were undertaken first hand.

Solid waste generation rate was found to vary from 0.13 kg/capita/day in Ogbomosho to 0.71 kg/capita/day in Ado-Ekiti. Factors affecting solid waste generation rates were identified. Typically, food waste was found to constitute close to 50 percent of overall municipal solid waste in Nigerian cities. This study shows that the rate of generation of plastics, water proof materials and diapers has assumed an upward trend. Due to the dysfunctional state of many municipal waste management authorities, many cities have been overrun by open dumps. For instance, more than 50 percent of residents of Maiduguri in northern Nigeria and Ughelli in southern Nigeria dispose of their waste in open dumps. Indiscriminate disposal of waste has also resulted in the preponderance of toxic heavy metals in agricultural soils and consequent bioaccumulation in plants as well as groundwater contamination.

The main limitation of this research is municipal waste management authorities do not have relevant data. Hence, there was heavy reliance on published materials. The status of waste management in Nigeria is very deplorable and therefore poses serious threats to public and environmental health. There is urgent need for both government and individuals to adopt holistic and sustainable waste management strategies in order to safeguard public/environmental health.

Findings from this paper can form a veritable resource for the formulation and implementation of sustainable municipal solid waste management framework and strategies in Nigeria.

While most studies on municipal solid waste management in Nigeria are focussed on selected cities of interest, this particular study cuts across most cities of Nigeria in order to present a broader and holistic view of municipal solid waste management in Nigeria. The paper has also unraveled core municipal solid waste management challenges facing Nigerian cities.

The dual epidemic of non-communicable diseases (NCDs) and human immuno-deficiency virus (HIV) in Sub-Saharan Africa has increased substantially in recent years, with cardiovascular disease representing a significant contributor to the regional burden of disease. Very little is known about the cardiovascular health of people deprived of their liberty in the region. The purpose of this study was to collate extant literature on the topic.

A scoping review mapped and described what is known about cardiovascular disease in prison populations in Sub-Saharan Africa. A systematic search of empirical literature with no date limitation was conducted in English. Sixteen studies representing six Sub-Saharan African countries (Cameroon, Nigeria, Guinea, Burkina Faso, Ghana and Ethiopia) were charted, categorised and thematically analysed.

Seven key themes were identified: custodial deaths and autopsy; cardiorespiratory fitness and exercise; cardiovascular disease and elderly people in prison; cardiovascular disease and women in prison; dietary deficiencies; influence of sleep patterns on cardiovascular disease; and other associated risk factors. Most natural deaths at autopsy of custodial deaths were due to cardiovascular disease. Cardiorespiratory fitness was low in prisons, and poor sleep patterns and dietary deficiencies are likely contributors to the burden of cardiovascular disease in prisons. The needs of elderly and female prison populations are ill-considered.

To the best of the authors’ knowledge, this is the first known attempt to scope extant literature on cardiovascular disease in Sub-Saharan African prisons. A strategic focus on the cardiovascular health of people in prison is warranted. Routine monitoring and expansion of existing prison health-care services and integration of NCD services with infectious disease (HIV and tuberculosis) programmes in prisons are required.

Community centers play a socio-economic and urban role of combining different communal necessities, that serve inhabitants, at different neighborhoods in cities. Their role emerged in importance as being a hub for improving and customizing quality of life experiences of the public. This research presents a code-based risk assessment tool for evaluating fire safety measures that can be adapted in the context of community centers. It also provides an exemplary case study to demonstrate its application.

The study identified the factors that render community centers as a high-risk type of facilities in fire events. Various fire codes and standards were reviewed to describe the relevant fire safety measures. A code-based fire risk assessment tool was developed and implemented, through a case study. A set of recommendations were developed to improve the fire safety conditions of the case study facility.

Several violations to fire safety were identified in the case study building. The findings led to identifying a set of recommendations to improve its fire safety conditions.

This research introduced a systematic approach to raise awareness about fire incidences and consequences in community centers, and provides facilities managers with a tool, to assess compliance based on international fire code requirements.

In fire events, community centers are considered as high-risk facilities that may lead to significant losses of human lives and damages to assets. It is significant to study the causes of fire, for ensuring effective prevention and safe operations.

Establishing a more sustainable built environment is an increasing global concern for the construction industry. Despite the intrinsic and extrinsic obstacles the stakeholders face, huge efforts are required to transition to a smooth, sustainable construction (SC) practice. This study identifies and discusses cogent obstacles to SC in developing nations.

The Preferred Reporting Item for systematic reviews and Meta-Analysis (PRISMA) approach was employed to establish research work in SC for developing countries. The databases used were Scopus and Web of Science. Meta-analysis of keywords was analysed thematically. The initial broad search returned 8,420 publications which were filtered and reviewed in-depth to fit the aim of the study, produced only 21 relevant publications from the years 2000–2021.

The four identified themes of obstacles to SC in developing countries are as follows: construction professional training and education, clients' attitudes and awareness, construction industries' culture and capacity and governments' regulation, policies and economy. The key barriers identified from the meta-analysis include inadequate training and education amongst construction professionals, poor execution of sustainability ethics, poor populace attitude towards sustainability, poor awareness and understanding, dearth of precise data and integrated study and inappropriate priorities about sustainability.

The originality in this study are themes drawn from millennium development goals (MDGs) and sustainable development goals (SDGs) publications related to SC. Consequently, the final framework presented a holistic approach to surmounting the established limitations and aided recommendations for future studies. Thus, setting a background for developing strategies to overcome the limitations and further attain sustainable development (SD).

As good as existing measurements of entrepreneurial potential (EP) may appear in the literature, they are fragmented, suffer from the lack of theory integration and clarity, are inadequately specified and assessed and the dimensions are unordered by importance. These limitations of EP metrics have hindered entrepreneurial practice and theory advancement. There is a risk of atomistic evolution of the topic among “siloed” scholars and room for repetitions without real progress. The purpose of this paper was to take stock of existing measurements from which the authors developed a new instrument that is brief and inclusive.

The authors followed several steps to develop and validate the new instrument, including construct domain name specification, literature review, structured interviews with entrepreneurs, face validation by experts, semantic validation and statistical validation after two waves of data collected on employee and entrepreneur samples.

A clear operational definition of EP is proposed and serves as a starting point towards a unified EP theory. The new EP instrument is made up of 34 items classified into seven dimensions, which in order of importance are proactive innovativeness, management skill, calculated risk-taking, social skill, financial literacy, entrepreneurial competencies prone to cognitive and heuristic biases and bricolage. The authors provide evidence for reliability and validity of the new instrument.

Although a model is not the model, the authors discuss several ways in which the new measurement model can be used by different stakeholders to promote entrepreneurship.

The authors discuss the domain representativeness of the new scale and argue that the literature can meaningfully benefit from a non-fuzzy approach to what makes the EP of an individual. By developing a new EP instrument, the authors set an important pre-condition for advancing entrepreneurial theory and practice.

This study reviews post-2009 literature on public sector internal auditing (IA) and addresses three interrelated research questions (RQ): How is research on the public sector IA being developed? What are the focus and criticisms of the literature on public sector IA? What is the future of public sector IA research?

We adopt a systematic literature review approach and analyze 78 peer-reviewed journal articles published between 2010 and 2019. We evaluate five criteria to identify the development of public sector IA research (RQ1), namely level of government, academic discipline, number of countries, geographic areas and MSCI country classification. Similarly, we use four criteria to present the focus and criticisms of the literature (RQ2), namely, type of organizational respondent, research instrument, theories and research theme examined. Finally, we use two criteria to propose new directions for future research (RQ3), namely, the directions resulted from RQ1 and RQ2 and the directions highlighted by the 10 most cited studies in the IA literature (i.e. out of the 78 papers identified).

We find an increase of publications up to 2017, most of which are single country–focused, particularly on emerging markets. Moreover, we note that IA has been studied at all government levels, most often at the local government level. Although we identify multiple research themes examined in the literature, most studies emphasize “governance” and “operational effectiveness” using quantitative analysis, without reference to any theory. By analyzing these key features, we critically interpret the challenges as well as the skepticism that may surface by researchers. Finally, considering implications from this stream of research and analyzing the most influential studies, we recommend new avenues for investigation such as comparative studies among countries and different markets that provide further evidence on the international and regional levels and studies on the effect of cultural, institutional and demographical characteristics in IA.

Our results will help researchers, practitioners and consultants to identify the key issues related with IA.

This study is the first to provide a systematic literature review on public sector IA. Furthermore, it develops insights, critical reflections and avenues for future research in this field.