A Novel Pythagorean Fuzzy Set–Based Risk-Ranking Method for Handling Human Cognitive Information in Risk-Assessment Problems

With the rapid evolution of the information age and the development of artificial intelligence, processing human cognitive information has become increasingly important. The risk-priority-number (RPN) approach is a natural language-processing method and is the most widely used risk-evaluation tool. However, the typical RPN approach cannot effectively process the various forms of human cognitive information or hesitant information provided by experts in risk assessments. In addition, it cannot process the relative-weight consideration of risk-assessment factors. In order to fully grasp the various forms of human cognitive information provided by experts during risk assessment, this paper proposes a novel Pythagorean fuzzy set–based (PFS) risk-ranking method. This method integrates the PFS and the combined compromise-solution (CoCoSo) method to handle human cognitive information in risk-assessment problems. In the numerical case study, this paper used a healthcare waste-hazards risk-assessment case to verify the validity and rationality of the proposed method for handling risk-assessment issues. The calculation results of the healthcare waste-hazards risk-assessment case are compared with the typical RPN approach, intuitionistic fuzzy set (IFS) method, PFS method, and the CoCoSo method. The numerical simulation verification results prove that the proposed method can comprehensively grasp various forms of cognitive information from experts and consider the relative weight of risk-assessment factors, providing more accurate and reasonable risk-assessment results

A NOVEL SUPPLIER SELECTION APPROACH BASED ON EXTENDED DATA ENVELOPMENT ANALYSIS UNDER A HESITANT FUZZY LINGUISTIC ENVIRONMENT

Supplier selection is a core supply chain issue. Choosing suitable suppliers will directly affect the success and sustainable development of the overall supply chain. Further, the assessment criteria of supplier selection include qualitative and quantitative assessment factors simultaneously. Thus, experts may give assessment criteria scores that include hesitant fuzzy information or incomplete information. These factors make the problem of choosing the right suppliers more complicated. The traditional average value approach and the traditional data envelopment analysis (DEA) method can only handle complete assessment criteria score information given by experts. They cannot simultaneously handle complete information, incomplete information, and hesitant information in the supplier selection process. In order to further handle this issue, this paper proposed a novel supplier selection approach based on extended DEA under a hesitant fuzzy linguistic (HFL) environment. The innovation of the proposed method lies in its capacity to simultaneously process complete information, incomplete information, and hesitant information in the supplier selection process. Furthermore, it can effectively solve a high number of duplicated DEA values of 1 for the DEA method. An illustrative example of consultant company selection was used to verify the rationality and correctness of the proposed approach. This study also compares the simulation results of the traditional average value method and the DEA method with those achieved using the proposed approach. The numerical test results show that the proposed approach can handle the above supplier selection issues under an HFL environment

Molecular pathways involved in the neurotoxicity of 6-OHDA, dopamine and MPTP: Contribution to the apoptotic theory in Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disorder characterized by a preferential loss of the dopaminergic neurons of the substantia nigra pars compacta. Although the etiology of PD is unknown, major biochemical processes such as oxidative stress and mitochondrial inhibition are largely described. However, despite these findings, the actual therapeutics are essentially symptomatical and are not able to block the degenerative process. Recent histological studies performed on brains from PD patients suggest that nigral cell death could be apoptotic. However, since post-mortem studies do not allow precise determination of the sequence of events leading to this apoptotic cell death, the molecular pathways involved in this process have been essentially studied on experimental models reproducing the human disease. These latter are created by using neurotoxic compounds such as 6-hydroxydopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or dopamine (DA). Extensive study of these models have shown that they mimick, in vitro and in vivo, the histological and/or the biochemical characteristics of PD and thus help to define important cellular actors of cell death presumably critical for the nigral degeneration. This review reports recent data concerning the biochemical and molecular apoptotic mechanisms underlying the experimental models of PD and correlates them to the phenomena occurring in human disease. © 2001 Elsevier Science Ltd.SCOPUS: re.jinfo:eu-repo/semantics/publishe