Strategists consider knowledge as a basic asset source through passing from source-oriented to knowledge-oriented approach in organizations, and the value of knowledge is evaluated based on how that ...knowledge is used in organization process, in order to produce goods and services. The purpose of this the study is to evaluate the impacts of aspects of knowledge-oriented leadership on innovative performance through considering mediating role of knowledge management practices in head quarter's domain of energy consultant engineering of Khorasan. The methodology of this research is descriptive study. Also, the purpose of the study is an applied research. The study population consisted of all employees in head quarter's domain of energy consultant engineering of Khorasan that includes 200 people. According to Morgan table, the sample size is 130 people that the questioners were randomly distributed among them. The questioner was used for data collection, and LISREL software was used for data analysis. The results of the study proved the impacts of aspects of knowledge-oriented leadership on innovative performance through considering mediating role of knowledge management practices in headquarters' domain of energy consultant. In this context, the present study hypothesis was confirmed.
Abstract
Generally, wind speed alters continuously during a day and leads to fluctuating output power of a wind farm (WF). Connecting such a WF to the transmission line of grid causes a malfunction ...in the performance of the backup zone of the distance relays due to the random nature of generation and the number of connected wind turbines (WF penetration). In this study, a new adaptive setting groups‐based method has been proposed to set the second zone of the distance relay in the grid with a WF equipped with a doubly fed induction generator. In this method, the authors have also taken into account the uncertainty of wind fluctuations and the availability of WT. A Markov model is developed to implement these features. To determine the impedance setting of each of the set groups of the second zone in the distance relays of the remote bus, the obtained impedances are clustered in four clusters by using the combination of K‐means and particle swarm optimization algorithms. Finally, the details of the analysis results of this issue have been compared with other methods available in the literature. The validity and accuracy of the proposed approach also have been assayed and confirmed.
In this study, the synchronization problem of the faulty chaotic gyrostat master–slave systems using a wavelet-based robust adaptive T-S fuzzy control is investigated. This control system is ...comprised of a wavelet T-S fuzzy network (TSFN) controller, a feedback controller and a robust controller. Within this scheme, the wavelet TSFN is used in two separate approaches. At the first approach, it is utilized to approximate the nonlinear functions of the gyrostat systems, and at the second approach, it is used to approximate the lumped fault function of the control system. The feedback controller is developed to initially control the underlying system, and a robust controller is an adaptive controller which is used to dispel the effects of the approximation errors on the tracking performance. The parameters of wavelet TSFN and the bound parameter of the robust controller are tuned on-line by the derived adaptive laws based on Lyapunov stability analysis. The wavelet block acts as a feature extractor, reduces the number of fuzzy rules and also acts as a normalization block. The Lyapunov stability of the closed-loop system, robustness against the parameters uncertainties, the external disturbances and the approximation errors, as well as the convergence of the tracking errors and boundedness of all signals in the closed-loop system, are guaranteed. Finally, the synchronization problem of the unknown chaotic gyrostat systems in the presence of parameter uncertainties, external disturbances and actuator faults is simulated to illustrate the effectiveness of the proposed control scheme.
Coronavirus disease 2019 (COVID-19) is a pandemic caused by the novel virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Knowing the virus's behavior and its persistence in ...different environments are crucial and will lead to the proper management of the disease. In this study, air, surface, and sewage samples were taken from different parts of referral hospitals for COVID-19.
Air samples were taken with impinger, surface samples with swabs, and sewage samples were taken from the hospital wastewater treatment plant. After viral genome extraction, a real-time RT-PCR test was applied to confirm the presence of SARS-CoV-2 RNA in the collected samples.
The virus genome could be traced in the wards and wastewater related to hospitalized COVID-19 patients. Overally, 29%, 16%, and 37.5% of air, surface, and sewage samples were positive for the SARS-CoV-2 genome, respectively.
Findings of such studies provide valuable results regarding the degree of contamination of hospital environments and the risk of virus transmission in different environments and among hospital staff and patients.
Purpose: To measure the choroidal thickness by enhanced depth imaging optical coherence tomography (EDI-OCT) in normal eyes.
Methods: In a prospective case series, 208 eyes of 104 normal Iranian ...subjects were enrolled. Complete ophthalmic examination was performed. Inclusion criteria were best corrected visual acuity (BCVA) ≥20/20, ≤ ±1 diopter of refractive error in either spherical or cylindrical components, normal intraocular pressure (IOP) and no systemic or ocular diseases. The choroidal thickness was measured by EDI-OCT subfoveally, and 1500 μm and 3000 μm nasal and temporal to the fovea.
Results: Mean age was 34.6 ± 9.8 years (range, 18-57 years). Mean subfoveal choroidal thickness was 363 ± 84 μm. Choroidal thickness was 292 ± 76 and 194 ± 58 μm at 1500 and 3000 μm nasal to the fovea, respectively, and 314 ± 77 and 268 ± 66 μm at 1500 and 3000 μm temporal to the fovea, respectively. There was no statistically significant difference in the choroidal thickness between sexes and laterality of the eyes. Choroidal thickness at fovea (P < 0.001) and at all extrafoveal locations decreased significantly for every 10 years increase in age.
Conclusion: In normal Iranian subjects participating in this study, mean choroidal thickness was comparable with other reports.
Neural cells are the most important components of the nervous system and have the duty of electrical signal transmission. Damage to these cells can lead to neurological disorders. Scientists have ...discovered different methods, such as stem cell therapy, to heal or regenerate damaged neural cells. Dental stem cells are among the different cells used in this method. This review attempts to evaluate the effect of biomaterials mentioned in the cited papers on differentiation of human dental pulp stem cells (hDPSCs) into neural cells for use in stem cell therapy of neurological disorders. We searched international databases for articles about the effect of biomaterials on neuronal differentiation of hDPSCs. The relevant articles were screened by title, abstract, and full text, followed by selection and data extraction. Totally, we identified 731 articles and chose 18 for inclusion in the study. A total of four studies employed polymeric scaffolds, four assessed chitosan scaffolds (CS), two utilised hydrogel scaffolds, one investigation utilised decellularised extracellular matrix (ECM), and six studies applied the floating sphere technique. hDPSCs could heal nerve damage in regenerative medicine. In the third iteration of nerve conduits, scaffolds, stem cells, regulated growth factor release, and ECM proteins restore major nerve damage. hDPSCs must differentiate into neural cells or neuron-like cells to regenerate nerves. Plastic-adherent cultures, floating dentosphere cultures, CS, polymeric scaffolds, hydrogels, and ECM mimics have been used to differentiate hDPSCs. According to our findings, the floating dentosphere technique and 3D-PLAS are currently the two best techniques since they result in neuroprogenitor cells, which are the starting point of differentiation and they can turn into any desired neural cell.
Organ-on-a-chip (OOC) systems are engineered nanobiosystems to mimic the physiochemical environment of a specific organ in the body. Among various components of OOC systems, biomimetic membranes have ...been regarded as one of the most important key components to develop controllable biomimetic bioanalysis systems. Here, we review the preparation and characterization of biomimetic membranes in comparison with the features of the extracellular matrix. After that, we review and discuss the latest applications of engineered biomimetic membranes to fabricate various organs on a chip, such as liver, kidney, intestine, lung, skin, heart, vasculature and blood vessels, brain, and multiorgans with perspectives for further biomedical applications.
One of the most important priorities in the medicinal mushrooms cultivation is the selection and preparation of the substrate, which depends on factors such as price and easy access to different ...lignocellulosic compounds. In order to investigate the effect of mixed and non-mixed agro-waste substrates on some vegetative, reproductive, nutritional and medicinal properties of two Iranian and Chinese strains of Ganoderma lucidum, the factorial experiment was conducted as a completely randomized design with three replications. The experimental substrates of different poplar wood chip (PWC), wheat bran (WB), soybean meal (SM), date palm leaf (DPL) and olive oil extraction waste (OOEW) were used. They were enriched with chemical supplements (ammonium nitrate, manganese sulfate and Nano manganese oxide) using two cultivation techniques (open bag door and Polika-Cotton) for fruiting body production.
The results showed that various substrates significantly affect dry weight, moisture content quantity, vegetative and fruit yield, total ganoderic acids content, total polysaccharide value and mineral elements amount (nitrogen, potassium and calcium) in fruiting body. The highest amount of N content in the fruiting body of both Iranian and Chinese strains (5.88 and 6.25 mg/100 g dry matter) was dedicated to the combined PWC + SM (70:30) substrate enriched with Nano manganese oxide supplement and Polika-Cotton method. The highest total fresh of Iranian and Chinese strains weight (109.60 and 127.66 g, respectively) obtained in the combined PWC + WB (70:30) substrate enriched with manganese sulfate. The highest amount of total ganoderic acids in fruiting organs in both strains (0.52 and 0.42 μg/mg dry matter) is achieved using a combined PWC + SM (70:30) enriched with manganese sulfate.
Introduction: To realize the global goals of eliminating hepatitis B virus (HBV) and hepatitis C virus (HCV) by 2030, it is necessary to monitor the status of disease among target populations and ...undertake the required interventions. This study is the third round of surveys to determine the prevalence of hepatitis B and C infections among incarcerated individuals in different provinces of Iran. Methods: This study was conducted in five provinces of Iran (including Kurdistan, Ardabil, West Azerbaijan, Markazi, and Semnan) in 2019. The subjects of the study were selected from incarcerated people in prisons of all provinces that had not been studied in the previous two rounds of the surveys (in 2015 and 2016) in Iran. In this study, 15 prisons were selected and 2475 incarcerated individuals were enrolled into the study based on the multistage sampling method; the selected subjects were surveyed and their dried blood spot (DBS) samples were collected to test HBsAg and HCV-Ab. In cases with a reactive result for HCV-Ab, an HCV-RNA test was also performed on their serum samples. The relationships between independent variables and outcomes were evaluated via logistic regression. Results: Of all participants (2475 subjects) enrolled in the study, 54.18% were selected from northern provinces and 45.82% from the central provinces. The prevalence of HCV-Ab and HBsAg among incarcerated individuals was 5.66% (95% CI: 4.81% to 6.64%) and 2.42% (95% CI: 1.89% to 3.11%), respectively. Among HCV-seropositive individuals, 73.68% (95% CI: 64.70% to 81.01%) had current HCV infection (detectable HCV-RNA). The results showed that histories of imprisonment, drug use, unprotected sexual contact, drug injection, tattooing, and younger age in the first-time drug use in incarcerated individuals significantly increased the risk of HCV transmission. Among these behaviors, drug injection was more likely than other behaviors to result in contracting HCV in incarcerated individuals (OR: 22.91; 95% CI: 14.92–35.18; p < 0.001). Conclusion: To achieve international and national strategies targeted to eliminate HCV and HBV by 2030, it is necessary to pay special attention to prisons in Iran. It is recommended to continue HBV vaccination of eligible people in prisons. Developing screening and treatment protocols for individuals with HCV infection in prisons can help the country to achieve HCV elimination goals.
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