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This paper aims to depict the mechanistic role of vitamin D on dementia prevention, relief of the severity and the complication of the disease. All papers indexed in scientific databases, including Scopus, Elsevier, PubMed, Embase and Google Scholar between 2000 and 2021 were extracted and discussed. To present the mechanistic role of vitamin D in declining the severity of dementia, keywords including dementia, vitamin D, oxidative stress, inflammation, amyloid beta-Peptides were used.

Dementia is a prevalent cognitive disorder worldwide, especially in elderly people, which is accompanied by serious disabilities. Besides genetic, biological and lifestyle factors are involved in the incidence of dementia. An unhealthy diet along with micronutrient deficiencies are among modifiable factors. Vitamin D is one of the important micronutrients in brain health. Besides the involvement in gene expression, bone mineralization, apoptosis, inflammation, skeletal maturation, neurotropic action and hemostasis of phosphate and calcium, vitamin D also exerts neuroprotective effects via genomic and non-genomic pathways.

Vitamin D up-regulates the expression of various genes involved in dementia incidence via various mechanisms. Decreasing oxidative stress and the neuro-inflammatory cytokines levels, regulation of the expression of alternated Proteins including Tau and Amyloid-ß, calcium homeostasis in the central nervous system and also vascular are considered main mechanisms.

Considering the importance of diet in preventing dementia, adherence to a healthy diet that provides essential nutrients to brain function seems to be urgent. Controlling serum levels of vitamin D periodically and providing vitamin D by related sources or supplements, if there is a deficiency, is recommended. Future studies are needed to clarify other related mechanisms.

The purpose of this study is to present a new failure mode and effects analysis (FMEA) approach based on fuzzy multi-criteria decision-making (MCDM) methods and multi-objective programming model for risk assessment in the planning phase of the oil and gas construction projects (OGCP) in Iran.

This research contains multiple steps. First, 19 major potential health and safety executive (HSE) risks in OGCP were classified into six categories with the Delphi method. These factors were distinguished by the review of project documentation, checklist analysis and consulting with experts. Then, using the fuzzy SWARA method, the authors calculated the weights of major HSE risks. Subsequently, FMEA and PROMETHEE approaches were used to identify the priority of main risk factors. Eventually, a binary multi-objective linear programming approach was developed to select the risk response strategies, and an augmented e-constraint method (AECM) was used.

Regarding the project triple well-known constraints of time, cost and quality, which organizations usually confront, the HSE risks of OGCP were identified and prioritized. Also, the appropriate risk response strategies were also suggested to the managers to be adopted regarding the situations.

The present research points at the HSE risks’ assessment integrating the fuzzy FMEA, step-wise weight assessment ratio analysis and PROMETHEE techniques with the AECM. Further to the authors’ knowledge, the quantitative assessment of the HSE risks of OGCP has not been done using the combination of the fuzzy FMEA, MCDM and AECMs.

This study aims to develop a framework for the optimal selection of construction project portfolios for a construction holding company. The objective is to minimize risks, align the portfolio with the organization’s strategic objectives and maximize portfolio returns and net present value (NPV).

The study develops a multi-objective genetic algorithm approach to optimize the portfolio selection process. The construction company’s portfolio is categorized into four main classes: water projects, building projects, road projects and healthcare projects. A mathematical model is developed, and a genetic algorithm is implemented using MATLAB software. Data from a construction holding company in Iraq, including budget and candidate projects, are used as a case study.

The case study results show that out of the 34 candidate projects, 13 have been recommended for execution. These selected projects span different portfolio classes, such as water, building, road and healthcare projects. The total budget required for executing the selected projects is $64.55m, within the organization’s budget limit. The convergence diagram of the genetic algorithm indicates that the best solutions were achieved around generation 20 and further improved from generation 60 onwards.

The study introduces a specialized framework for project portfolio management in the construction industry, focusing on risk management and strategic alignment. It uses a multi-objective genetic algorithm and risk analysis to minimize risks, increase returns and improve portfolio performance. The case study validates its practical applicability.

This study contributes to project portfolio management by developing a framework specifically tailored for construction holding companies. Integrating a multi-objective genetic algorithm allows for a comprehensive optimization process, taking into account various objectives, including portfolio returns, NPV, risk reduction and strategic alignment. The case study application provides practical insights and validates the effectiveness of the proposed framework in a real-world setting.

Production of waste has been increased exponentially due to world industrialization and urban and machine life expansion. On the other hand, the outbreak of the COVID-19 coronavirus quickly became a global crisis. This crisis has added a large amount of waste to urban waste. The purpose of this study is to create cooperation between municipal waste collector contractors.

Thus, a mathematical model is proposed under uncertain conditions, which includes the volume of municipal waste and infectious waste including personal protective equipment and used equipment for patients. To reduce total costs, the results are evaluated with four cooperative game theory methods such as Shapley value, t value, core center and least core. Ultimately, the saved cost by cooperation in each coalition is allocated fairly among the contractors. Finally, a comparison was made between the solution methods based on the value of the objective function and the solution time.

The results indicate that the proposed cooperative method increases cost savings and reduces the fine of residual waste. Therefore, it can be mentioned that this kind of cooperation would finally result in more incentives for contractors to form larger coalitions. Genetic algorithms were used to solve the large-scale model.

The proposed model boosts the current understanding of waste management in the COVID-19 pandemic. The paper adds additional value by unveiling some key future research directions. This guidance may demonstrate possible existing and unexplored gaps so that researchers can direct future research to develop new processes.

This study aims to explore the synthesis, characteristics and utilization of polymer composites integrated with cutting-edge pigments.

The incorporation of advanced pigments introduces functionalities such as enhanced mechanical strength, thermal stability, ultraviolet resistance and color stability, thus extending the range of applications in diverse fields including automotive, aerospace, electronics and construction.

This review discusses the mechanisms underlying the property enhancements achieved through the incorporation of advanced pigments and highlights recent developments in the field.

Polymer composites incorporating advanced pigments have garnered significant attention in recent years because of their potential to enhance various material properties and broaden their applications. This paper explores the fabrication methods of polymer composites reinforced with organic/inorganic advanced pigments in brief along with their characteristics and applications.

Researchers and practitioners have recently been interested in corporate sustainability performance (CSP). However, knowledge on measuring CSP is limited. Many CSP-measurements are eclectic, without guidance for contextual applications. This paper aims to develop a conceptual framework that categorizes, explains and evaluates measurements based on their accuracy and precision and provides a guideline for their context-specific application.

The authors conducted a systematic literature review of an initial sample of 1,415 papers.

The final sample of 74 papers suggested four measurement categories: isolated indicators, indicator frameworks, Sustainability Balanced Scorecards (SBSC) and Sustainability Performance Measurement Systems (SPMS). The analysis reveals that isolated indicators are inaccurate and imprecise, limiting their application to organizations with delimited, specific measurements of parts of CSP due to the risk of a GIGO-effect (i.e. low-quality input will always produce low-quality output). CSP-indicator frameworks are imprecise but accurate, making them applicable to organizations that handle a more significant amount of CSP data. They have a risk of greensplashing, i.e. many indicators not connected to the industry, organization or strategy. In contrast, SBSCs are precise but inaccurate and valuable for organizations desiring a comprehensive strategic management tool with limited capacity to handle sustainability issues. They pose a risk of the streetlight effect, where organisations do not measure relevant indicators but what is easy to measure.

The ideal CSP-measurement was identified as SPMSs, which are both precise and accurate. SPMSs are useful for organizations with complex, comprehensive, connected and tailored indicators but are methodologically challenging.