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In the field of innovation, individual innovative performance also has an important impact on team and organizational innovative performance, thus it is necessary to identify factors that increase individual innovative performance. One key to unlock individual innovative performance is empowering leadership. Drawing on the Ability-Motivation-Opportunity (AMO) theoretical framework, this study investigates the cross-level influence of team-directed empowering leadership on subordinates' innovative performance and verifies the mediating role of creative self-efficacy (A), intrinsic motivation (M), team knowledge sharing (O) and the moderating effect of feedback seeking climate.

With a sample of 102 teams and 722 employees, this study uses Mplus7.4 software to carry out cross-level model analysis based on MSEM multilevel mediation test methodology.

The results from cross-level analysis indicate that: (1) Team-directed empowering leadership has a significant positive impact on subordinates' innovative performance. (2) Team-directed empowering leadership enhances subordinates' innovative performance through the improvement of creative self-efficacy, intrinsic motivation and team knowledge sharing. (3) Based on the feedback perspective, feedback seeking climate moderates the relationship between team-directed empowering leadership and creative self-efficacy, intrinsic motivation and team knowledge sharing.

This study introduced the AMO theory into the research on cross-level mediating mechanism between team-directed empowering leadership and subordinates' innovative performance, which broadens the theoretical research perspective. Considering the difference between empowering leadership and laissez-faire leadership and the guiding role of feedback, this study selects feedback seeking climate as a moderator in view of feedback, which riches the contingency factors on the cross-level effect of team-directed empowering leadership.

Increased ethanol accumulation during ethanol fermentation generates stress in yeast cells, which finally reduces the fermentation performance and efficiency. Trehalose, a potential stress protectant, has been reported to regulate the response of yeast to diverse environmental stresses. This study aimed to explore how exogenous trehalose application affects the survival, transcriptome and antioxidant enzymes of Wickerhamomyces anomalus grown under ethanol stress conditions.

Exogenous trehalose was applied to the growth condition of W. anomalus, and optical densitometric method was used to detect contents of intracellular trehalose and MDA and activities of CAT and SOD. The survival was evaluated using spot analysis. Differentially expressed genes (DEGs) were identified through transcriptomics analysis.

The results showed that ethanol stress induced the accumulation of intracellular trehalose, with further exogenous trehalose application improving the survival and alleviating oxidative stress in ethanol-stressed W. anomalus. Transcriptomic results showed that trehalose has pleiotropic regulating effects on ethanol-stressed W. anomalus since most DEGs annotated to energy metabolism, amino acid metabolism, translation, folding, sorting and transport were affected post trehalose addition. Therefore, it is found that trehalose protected W. anomalus against ethanol stress, and these findings provide interesting insights into the mechanistic role of trehalose in improving ethanol stress tolerance of W. anomalus.

(1) Protective effect of exogenous trehalose addition on the survival of ethanol-stressed W. anomalus was proved. (2) Exogenous trehalose addition could partly alleviate oxidative stress induced by ethanol stress and affect transcriptome in W. anomalus.

Recent studies have shown that hyperuricemia is a predictor of non-communicable disease and an increment of mortality rate. Also, elevated serum uric acid may be associated with obesity in the adult population. This study aims to evaluate the association between serum uric acid levels with metabolic parameters and risk of obesity in the Iranian population.

The cross-sectional study was done on 550 participants, who were referred to a hospital for elective angiography in Rasht, Iran; anthropometric indices (waist circumference (WC) and body mass index (BMI)) and hematological factors were measured using the standard approaches. Based to the angiography results, the severity of atherosclerosis was defined.

The mean (SD) concentration of serum uric acid for all participants was 5.15 (1.37) mg/dl. Individuals who were at the highest tertile had higher mean (SD) of weight (p = 0.004), creatinine and blood urea nitrogen (p < 0.001) lower fasting blood sugar (FBS) (p = 0.000) and HbA1c (p = 0.016), and they were mostly men compared with those in the lowest tertile. After adjusting for confounders, FBS (ß = –0.145, p = 0.001) and HbA1c (%) (ß = –0.130, p = 0.019) had inverse and weight (ß = 0.156, p = 0.001) had direct association with serum uric acid. After adjustment for additionally potential confounders subjects in the highest tertile of serum uric acid had 92 per cent higher chance of obesity compared with subjects in the lowest tertile (OR 1.92; 95 per cent CI 1.13, 3.23).

The present study has concluded that increase serum uric acid related to high risk of obesity and low mean of FBS and HbA1c.

It is argued that COVID-19 patients show various neuropsychiatric symptoms, including fatigue, depression and anxiety. On the other hand, epidemiological and experimental evidence indicated that green tea could potentially have antiviral effects and ameliorate psychiatric disorders. However, there is a lack of clinical evidence. The purpose of this study was to investigate whether drinking green tea can clinically improve psychiatric complications of COVID-19 infection.

This study included 40 patients with laboratory confirmed mild-to-moderate COVID-19 disorder in the current randomized open-label controlled trial. Patients were instructed to include three cups/day of green tea (intervention) or black tea (control) to their usual diet for four weeks immediately after diagnosis of the disease. At the study baseline and after the intervention, the enrolled patients’ fatigue, depression and anxiety were assessed by the Chalder Fatigue Scale, Beck Depression Inventory-Fast Screen and State-Trait Anxiety Inventory questionnaires.

A total of 19 COVID-19 cases in the intervention group (mean age = 52 years) and 14 cases (mean age = 50 years) in the control group completed the study. Analysis of covariance adjusted for baseline levels, and confounders revealed that those who consumed three cups/day of green tea compared to the patients who received black tea experienced significantly lower fatigue, depression and state and trait anxiety levels (adjusted means for fatigue = 12.3 vs 16.2 (P = 0.03), depression = 0.53 vs 1.8 (P = 0.01), 37.4 vs 45.5 (P < 0.01) and 37.9 vs 45.2 (P < 0.01)).

The open-label design may bias the evaluation of the self-reported status of fatigue, depression or anxiety as the main outcomes assessed. Moreover, as this study did not include patients with severe COVID-19, this might affect the generalizability of the present results. Thus, the recommendation of daily drinking green tea may be limited to the subjects diagnosed with mild-to-moderate type of infection or those with long-term neuropsychiatric complications owing to COVID-19. Besides, considering the ethical issues, this study could not exclude the drug therapy’s confounding effects; thereby, this point should be considered when interpreting the current results. Besides, it is worth noting that Guilan province in the north of Iran is recognized as a tea (and particularly green tea) producing region; thereby, it is an available and relatively inexpensive product. Considering this issue, the recommendation to consume this medicinal plant in adjunct to the routine treatment approach among patients with mild-to-moderate COVID-19 based on its beneficial effects may be widely accepted.

Green tea consumption could be considered an option to combat COVID-19 associated psychological complications, including fatigue, depression and anxiety among patients suffering from mild-to-moderate type of this viral infection.

To the best of the authors’ knowledge, in this study, for the first time, the effects of green tea compared to black tea on COVID-19 associated fatigue, depression and anxiety status within an open-label controlled trial have been investigated.

It has been revealed that application of the differential form of Eringen’s nonlocal elasticity theory to some cases (e.g. cantilevers) leads to paradoxical results, and recourse must be made to the integral version of Eringen’s nonlocal model. The purpose of this paper, within the framework of integral form of Eringen’s nonlocal theory, is to study the bending behavior of nanoscale plates with various boundary conditions using the isogeometric analysis (IGA).

The shear deformation effect is taken into account according to the Mindlin plate theory, and the minimum total potential energy principle is utilized in order to derive the governing equations. The relations are obtained in the matrix-vector form which can be easily employed in IGA or finite element analysis. For the comparison purpose, the governing equations are also derived based on the differential nonlocal model and are then solved via IGA. Comparisons are made between the predictions of integral nonlocal model, differential nonlocal model and local (classical) model.

The bending analysis of nanoplates under some kinds of edge supports indicates that using the differential model leads to paradoxical results (decreasing the maximum deflection with increasing the nonlocal parameter), whereas the results of integral model are consistent.

A new nonlocal formulation is developed for the IGA of Mindlin nanoplates. The nonlocal effects are captured based on the integral model of nonlocal elasticity. The formulation is developed in matrix-vector form which can be readily used in finite element method. Comparisons are made between the results of differential and integral models for the bending problem. The proposed integral model is capable of resolving the paradox appeared in the results of differential model.

This study aimed to Simultaneous matching of color and antimicrobial properties of silk fabric treated with silver nanoparticle. The antimicrobial finishing using silver nanoparticles (AgNPs) is one of the most important finishing processes in the textile industry. Color matching is widely applied in the textile industry, but there has been a need for the prediction of AgNPs concentration for the matching of dyed silver-treated samples.

In this research, the silk fabrics were dyed with various concentrations of C.I. Acid Red 359 dye at 0.5, 1, 1.5 and 2 per cent (w/w). The dyed fabrics were then coated with AgNPs in several concentrations at 0.015, 0.030, 0.050, 0.100 and 0.250 ml/l. The prediction of dye and AgNPs concentrations were evaluated using single constant color matching and artificial neural network techniques.

The obtained results indicate that the accuracy of dye concentration prediction, as well as AgNPs concentration prediction, was improved by using a neural network method. Also, the correlation between actual and predicted dye and AgNPs concentrations in the best neural networks is more than the single constant color matching method.

Simultaneous antibacterial and color matching of nanosilver-treated fabric is novel. This method achieved acceptable accuracy for antibacterial and color matching.

Based on the molecular mechanics approach, the purpose of this paper is to analytically investigate the torsional buckling behavior of single-walled silicon carbide nanotubes (SiCNTs) with different values of diameter and chiral angles.

To this end, the mechanical properties and atomic structure of a silicon carbide (SiC) sheet are evaluated based on the density functional theory (DFT) within the framework of the generalized gradient approximation. After that force constants of the total potential energy are theoretically obtained through establishing a linkage between the viewpoints of the quantum mechanics and molecular mechanics. Explicit expressions are presented to obtain the critical buckling shear strain corresponding to different types of chirality. The present model is capable to calculate the torsional buckling behavior of SiCNTs related to various chiral angles. The critical buckling shear strain is obtained for various types of chirality and compared with each other.

It is concluded that for all diameters, zigzag nanotubes are more stable than armchair ones. Besides it is found that the minimum critical buckling shear strain is for nanotubes with (n, n/2) chiral vector.

Investigating the torsional buckling behavior of single-walled SiCNTs with different values of diameter and chiral angle. Obtaining the mechanical properties and atomic structure of the SiC sheet based on the DFT calculations. Establishing a linkage between the molecular mechanics and quantum mechanics and obtaining the force constants of the molecular mechanics. Presenting the closed-form expression to calculate the critical buckling shear strain of single-walled SiCNTs corresponding to various types of chirality.

Artificial intelligence (AI) methods, such as genetic algorithm (GA) and adaptive neuro-fuzzy inference system (ANFIS), are capable of providing superior solutions for the simulation and the modeling of complex problems. The purpose of this study is to estimate the dye and the silver nanoparticle (AgNP) concentrations of silver nanoparticle-treated silk fabrics by the aforementioned methods.

In this study, the color and the antimicrobial properties of silver nanoparticle-treated silk fabrics were matched by using the GA technique based on spectrophotometric color matching. The ANFIS method was also used; this method is based on the grid partitioning algorithm across four different methods. The first and second methods are provided for dye concentration prediction, and the third and the fourth methods are given for AgNP concentration prediction.

The mean of absolute error and root mean square (RMS) of the best dye concentration prediction by the ANFIS method based on the second method are 0.087 and 0.103, respectively. In addition, the mean of the absolute error and the RMS of the best results for AgNP concentration prediction by the ANFIS method by using the third method is 0.002 and 0.003, respectively. The obtained results indicate that the performance of the ANFIS method is better than the GA method.

The simultaneous prediction of the color and the antimicrobial properties of silver nanoparticle-treated silk fabrics was performed by using the GA and the ANFIS. The suggested method led to acceptable accuracy for color and antibacterial matching.

The purpose of this paper is to present a stochastic p-robust data envelopment analysis (DEA) model for decision-making units (DMUs) efficiency estimation under uncertainty. The main contribution of this paper consists of the development of a more robust system for the estimation of efficiency in situations of inputs uncertainty. The proposed model is used for the efficiency measurement of a commercial Iranian bank.

This paper has been arranged to launch along the following steps: the classical Charnes, Cooper, and Rhodes (CCR) DEA model was briefly reviewed. After that, the p-robust DEA model is introduced and then calculated the priority weights of each scenario for CCR DEA output oriented method. To compute the priority weights of criteria in discrete scenarios, the analytical hierarchy analysis process (AHP) is used. To tackle the uncertainty of experts’ opinion, a synthetic technique is applied based on both robust and stochastic optimizations. In the sequel, stochastic p-robust models are proposed for the estimation of efficiency, with particular attention being paid to DEA models.

The proposed method provides a more encompassing measure of efficiency in the presence of synthetic uncertainty approach. According to the results, the expected score, relative regret score and stochastic P-robust score for DMUs are obtained. The applicability of the extended model is illustrated in the context of the analysis of an Iranian commercial bank performance. Also, it is shown that the stochastic p-robust DEA model is a proper generalization of traditional DEA and gained a desired robustness level. In fact, the maximum possible efficiency score of a DMU with overall permissible uncertainties is obtained, and the minimal amount of uncertainty level under the stochastic p-robustness measure that is required to achieve this efficiency score. Finally, by an example, it is shown that the objective values of the input and output models are not inverse of each other as in classical DEA models.

This research showed that the enormous decrease in maximum possible regret makes only a small addition in the expected efficiency. In other words, improvements in regret can somewhat affect the expected efficiency. The superior issue this kind of modeling is to permit a harmful effect to the objective to better hedge against the uncertain cases that are commonly ignored.

In uncertain and emerging conditions, businesses must adopt new strategies to compete and survive the changing and unstable environment. This research seeks to investigate the role of dynamic capabilities in the competitiveness of startups, emphasizing resilience and strategic alignment.

Isfahan Scientific and Research Town has always been a pioneer in the field of science and technology in Iran and is known as the most extensive technology and knowledge-based complex in Iran. The sample size of 300 companies active in the startup field was selected using a simple random sampling method. Questionnaires were collected from the managers of technological startup companies in Isfahan, and the SEM model was used to analyze the data.

This research shows that dynamic capabilities in terms of coordination, flexibility and integration significantly impact competitiveness. Resilience and strategic alignment also increase the organization’s performance and strengthen the organization in gaining a more competitive advantage in the industry.

Finally, dynamic capabilities indirectly affect competitiveness through resilience and strategic alignment. This shows a need for strategic alignment and resilience to change advantage shape in dynamic conditions.