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Finding the suitable solution to optimization problems is a fundamental challenge in various sciences. Optimization algorithms are one of the effective stochastic methods in solving optimization problems. In this paper, a new stochastic optimization algorithm called Search Step Adjustment Based Algorithm (SSABA) is presented to provide quasi-optimal solutions to various optimization problems. In the initial iterations of the algorithm, the step index is set to the highest value for a comprehensive search of the search space. Then, with increasing repetitions in order to focus the search of the algorithm in achieving the optimal solution closer to the global optimal, the step index is reduced to reach the minimum value at the end of the algorithm implementation. SSABA is mathematically modeled and its performance in optimization is evaluated on twenty-three different standard objective functions of unimodal and multimodal types. The results of optimization of unimodal functions show that the proposed algorithm SSABA has high exploitation power and the results of optimization of multimodal functions show the appropriate exploration power of the proposed algorithm. In addition, the performance of the proposed SSABA is compared with the performance of eight well-known algorithms, including Particle Swarm Optimization (PSO), Genetic Algorithm (GA), Teaching-Learning Based Optimization (TLBO), Gravitational Search Algorithm (GSA), Grey Wolf Optimization (GWO), Whale Optimization Algorithm (WOA), Marine Predators Algorithm (MPA), and Tunicate Swarm Algorithm (TSA). The simulation results show that the proposed SSABA is better and more competitive than the eight compared algorithms with better performance. [ABSTRACT FROM AUTHOR]

Background: One of the global problems is to control the coronavirus epidemic, and the role of different medicines is still unknown to policymakers. This study was conducted to evaluate the effects of losartan on the mortality rate of COVID-19 in hypertensive patients.Methods: The research sample of analytical study included 1458 patients presenting to COVID-19 diagnostic centers in Yazd that were examined in the first six months of 2020. Data were analyzed using descriptive statistics as well as chi-square, Fisher's exact test, t test, and logistic regression.Results: Of 1458 subjects that were studied, 280 were hypertensive of whom 179 tested positive for SARS-CoV-2 PCR. The results showed a lower chance of death by more than 5 times in hypertensive patients who used losartan (P = 0.003). Moreover, regarding the effect of losartan on the prevention of COVID-19 in hypertensive patients, it was found that this medicine played a protective role although this relationship was not statistically significant (P = 0.86).Conclusions: The results showed that losartan reduced the chance of mortality in hypertensive patients. It is recommended that the effect of losartan and other blood pressure medicines on COVID-19 patients be investigated in larger studies as well as laboratory investigations. [ABSTRACT FROM AUTHOR]

In this paper, a multi-objective mixed-integer programming model is developed to cope with the multi-mode resourceconstrained project selection and scheduling problem, aiming to minimize the makespan, maximize the net present value of project cash flows, and minimize the fluctuation of renewable resource consumption between consecutive time periods. Moreover, activities are considered to be subject to generalized finish-to-start precedence relations, and time-varying resource usage between consecutive time periods. To assess the performance of the proposed model, 30 different-sized numerical examples are solved using goal programming, epsilon constraint, and augmented epsilon constraint methods. Afterward, Tukey test is used to statistically compare the solution methods. Moreover, VIKOR method is used to make an overall assessment of the solution methods. Statistical comparisons show that there is a significant difference between the mean of the resource leveling objective functions for all the solution methods. In other words, goal programming statistically outperforms other solution methods in terms of the resource leveling objective function. This is not the case for the other objective functions and CPU times. In addition, results of the VIKOR method indicate that the goal programming method outperforms the other solution methods. Hence, goal programming method is used to perform some sensitivity analyses with respect to the main parameters of the problem. Results show that by improving any of the parameters at least one objective function improves. However, due to the conflicting nature and the impact of weights of objective functions, in most cases, the trend are not constant to describe a general pattern. [ABSTRACT FROM AUTHOR]

In this paper, a ranking procedure is proposed for the order-of-magnitude qualitative reasoning problem. To this end, a preference degree was suggested for comparing a set of k-dimensional vectors of qualitative labels to provide a criterion to interpret the concept of 'preference' between two k-dimensional vectors of qualitative labels. Some useful properties of the proposed preference degree were also examined and discussed. It was shown that the proposed preference degree can satisfy the common and desired properties expected in the space of k-dimensional vectors of qualitative labels. Numerical examples were also employed to illustrate the proposed ranking method. Three application examples were used to show the applicability of the proposed ranking method in a single criterion group decision-making (SAGDM) and multiple criteria group decision-making (MAGDM). Moreover, the proposed preference degree was compared with a conventional method in terms of ranking the k-dimensional vector of qualitative labels. Unlike the proposed method, the numerical evaluations revealed that the previous techniques are not applicable to some situations in decision-making. [ABSTRACT FROM AUTHOR]

[Display omitted] Silane (sol–gel)-based coatings have been introduced as an eco-friendly system for reducing the metals' corrosion in NaCl solutions. However, due to the lack of active protection property for this type of coatings, their modification is totally recommended for achieving durable protection properties. The present study introduces Beta-cyclodextrin (β -CD) as a novel/effective organic nano-container for Benzimidazole (BM) encapsulation to obtain reliable active protection property via a controlled-release property. The chemical structure of the β -CD-BM macromolecule was explored by Fourier-transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD), and Ultraviolet–visible spectroscopy (UV–Vis). Besides, the Electrochemical Impedance Spectroscopy (EIS) and polarization (potentiodynamic) tests were carried out for investigating the inhibition impacts of the constructed containers. The exposed and unexposed samples' surfaces were analyzed by Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive Spectroscopy (EDS)/mapping, and Grazing incidence X-ray diffraction (GIXRD) experiments. Also, the EIS test was conducted over the Silane-based composite film (SCF) for analyzing the anti-corrosion performance of the constructed composites. The EIS achievements demonstrated that by the addition of β -CD-BM complexes to the saline solution, the mild steel corrosion was mitigated by about 84%. The EIS results also displayed that the total resistance of the modified composite was enhanced from 5540 Ω.cm2 to 10967 Ω.cm2 and the intact coating provided a total resistance of 80254 Ω.cm2. The dispersion-corrected Density Functional Theory (DFT)-D explorations ascertained the inclusion capacity of benzimidazole inside the β -CD. The Monte Carlo/Molecular Dynamics (MC/MD) calculations strongly affirmed the adsorption of BM and β -CD-BM over the substrate. [ABSTRACT FROM AUTHOR]

The presence of iron sulfide minerals and the lack of dissolution of iron in these minerals in hydrochloric acid causes the titration results to be not accurate, and consequently, the obtained Fe grades to be less than the actual amount. In the proposed method, Fe–S bonds are broken in nitric acid and then iron is dissolved using hydrochloric acid. Increased safety and reduced analysis time are some of the advantages of this method. [ABSTRACT FROM AUTHOR]

Background: Patients with multiple sclerosis face numerous problems during their lifetime. A self-report measurement of disease - specific problems is required to be developed for patients with multiple sclerosis based on different cultural factors. Accordingly, this can advance our understanding on the disease-specific problems for care planning as well as improving coping ways and quality of life. This study aimed to develop and validate the scale of disease-specific problems of Multiple Sclerosis.Methods: This was an exploratory sequential mixed method study conducted in three phases. Correspondingly, in the first phase, the concept of disease-specific problems was defined using the content analysis approach in patients with MS. In the second phase, the item pool was generated from the findings of the first phase, and in the third phase, psychometric properties of the scale, including face, content, and construct validity and reliability, were evaluated.Results: After examining both validity and reliability, 28 items were developed in the final questionnaire. As well, by performing the factor analysis, five factors were revealed as follows: physical problems, psychological problems, emotional problems, family problems, and socio-economic problems. Internal consistency and stability of the questionnaire were calculated as 0.82 and 0.90, respectively, indicating an excellent reliability.Conclusion: The 28-item questionnaire is valid and reliable for measurement of level of disease - specific problems in Iranian people with MS. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of exposure to pesticides and the prevalence of type 2 diabetes (T2D). In a cross-sectional study with a population of 9088, the data were collected through Persian Adult Cohort Questionnaire in Shahedieh area of Yazd, Iran. Based on the results, variables such as age, gender, body mass index, physical activity, and education level in the studied population had a significant association with the prevalence of diabetes. Although the obtained data in this study did not show a relationship between exposure to pesticides and the risk of developing T2D, further prospective studies are needed to determine the association between exposure to pesticides and the development of T2D. [ABSTRACT FROM AUTHOR]