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Schools adopt student voice as a means of identifying educational problems and weaknesses for improvement. In recent decades, student voice work has gained momentum, and, more importantly, dwelling on hearing students has been noticed as a way of facilitating educational decisions for school reforms. To this end, the study, drawing upon a qualitative research method, investigated the student voice in schools within the context of Iran in an effort to determine what obstacles they face in education. Data was collected through an open‐ended questionnaire. Employing thematic content analysis, the major themes and patterns were extracted for codifications. The findings illustrated that students specified four major problems, including resources (books), processes (rules), relationships (teachers, parents, staff) and environment (school). To conclude, student voice needs to be embedded in the educational system of Iran if stakeholders seek improvement and reform in schools in the near future. [ABSTRACT FROM AUTHOR]

Kojic acid (KA) is a hydroxypyranone natural metabolite mainly known as tyrosinase inhibitor. Currently, this compound is used as a whitening agent in cosmetics and as an anti‐browning agent in food industry. Given the easy‐manipulation in different positions of the KA molecule, many investigations have been carried out to find new tyrosinase inhibitors derived from KA. Beside anti‐tyrosinase activity, many KA‐based compounds have been designed for targeting other enzymes including human neutrophil elastase, catechol‐O‐methyltransferase, matrix metalloproteinases, monoamine oxidase, human lactate dehydrogenase, endonucleases, D‐amino acid oxidase, and receptors such as histamine H3 and apelin (APJ) receptors. This review could help biochemists and medicinal chemists in designing diverse KA‐derived enzyme inhibitors. [ABSTRACT FROM AUTHOR]

Background: Curcumin, a natural polyphenolic compound, is proposed as a potential treatment option for patients with coronavirus disease by inhibiting the entry of virus to the cell, encapsulation of the virus and viral protease, as well as modulating various cellular signaling pathways. In this study, the efficacy and safety of nanocurcumin oral formulation has been evaluated in patients with mild‐moderate Coronavirus disease 2019 (COVID‐19) in outpatient setting. Methods: In this triple‐blind randomized placebo‐controlled clinical trial, sixty mild to moderate COVID‐19 patients in outpatient setting who fulfilled the inclusion criteria were randomly allocated to treatment (n = 30) group to receive oral nanocurcumin formulation (Sinacurcumin soft gel which contains 40 mg curcuminoids as nanomicelles), two soft gels twice a day after food for 2 weeks or placebo (n = 30) group. Patients' symptoms and laboratory data were assessed at baseline and during follow‐up period and compared between two groups. Results: All symptoms except sore throat resolved faster in the treatment group and the difference was significant for chills, cough and smell and taste disturbances. The CRP serum level was lower in the treatment group at the end of two weeks and the lymphocyte count was significantly higher in treatment group. No significant adverse reaction reported in the treatment group. Conclusion: Oral nanoformulation of curcumin can significantly improve recovery time in patients with mild to moderate COVID‐19 in outpatient setting. Further studies with larger sample size are recommended. [ABSTRACT FROM AUTHOR]

During normal operation of a conventional Modular Multilevel Converter (MMC), half of its capacitors remain bypassed at any time instant, increasing the total required capacitance for converter operation, and in turn leading to a larger size and volume MMC for a target capacitor voltage ripple limit. This paper presents a novel MMC topology that utilizes all converter capacitors at all times during the operation. Therefore, the total required capacitance for generating a voltage waveform with the same number of levels and the same target capacitor voltage ripple limit is greatly reduced compared to conventional MMCs. The new topology inherits all the desirable features of conventional MMCs such as modularity, reliability, and scalability, and is compatible with many of the previously proposed control techniques for conventional MMCs. The process of synthesizing the proposed MMC topology and a new voltage balancing scheme as well as the dynamic model and capacitor sizing procedure for the proposed MMC are reported in the paper. Furthermore, experimental results are presented to evaluate the performance of the proposed converter. [ABSTRACT FROM AUTHOR]

Cardiovascular disease is the leading cause of death globally. Coronary artery disease (CAD) is a chronic inflammatory disease usually caused by atherosclerosis, in which the coronary arteries become narrowed by atheromatous plaque. Plaques in atherosclerosis are formed through the accumulation of lipids and various immune cells. Both adaptive and innate immune systems are involved in the pathogenesis of atherosclerosis and facilitate plaque formation and disease progression. Almost all immune system cells, including neutrophils, B cells, T cells monocytes, macrophages, foam cells, and dendritic cells (DCs), play a vital role in atherosclerotic plaque. Atherogenesis, the normal function of the endothelium, is initially disrupted and, then, cells of the immune system are recruited to the endothelium following increased expression of cell adhesion molecules. Accumulation of immune cells and lipids leads to the formation of a necrotic nucleus. As the disease progresses, smooth muscle cells form fibrous layers, whose rupture results in exposing the necrotic nucleus and thrombosis. Accordingly, the present review was conducted to determine the role of different cells in innate and adaptive immune systems in inhibition and progression of atherosclerosis. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a chronic inflammatory disease with high mortality worldwide. The reverse cholesterol transport pathway in macrophage plays an important role in the pathogenesis of coronary artery disease (CAD) and is strongly controlled by regulatory factors. The microRNAs can promote or prevent the formation of atherosclerotic lesions by post‐transcriptional regulation of vital genes in this pathway. Therefore, this study was conducted to investigate the relationship between the expression levels of miR‐27a, miR‐329, ABCA1, and ABCG1 genes and serum levels of hs‐CRP, ox‐LDL, and indices of oxidative stress in the patients with established CAD and controls. A total of 84 subjects (42 patients with CAD and 42 controls) were included in this study. Expression levels of miR‐27a‐3p, miR‐329‐3p, ABCA1, and ABCG1 genes in the peripheral blood mononuclear cells (PBMCs) and serum concentration of hs‐CRP and ox‐LDL were measured by real time‐PCR and ELISA, respectively. Also, oxidative stress parameters in the serum were evaluated by ferric‐reducing antioxidant power (FRAP) and malondialdehyde (MDA) assays. ABCA1 and ABCG1 gene expression in PBMC and serum concentration of FRAP were significantly lower in the CAD group compared to the control group. Expression levels of miR‐27a and miR‐329 and serum levels of hs‐CRP, ox‐LDL, and MDA were significantly higher in the CAD group compared to the control group. Serum levels of hs‐CRP, ox‐LDL, and expression level of miR‐27a have inversely related to ABCA1 and ABCG1 gene expression in all the subjects. An increase in the expression levels of miR‐27a and miR‐329 may lead to the progression of atherosclerosis plaque by downregulating the expression of ABCA1 and ABCG1 genes. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) and Crohn's disease (CD) are two major forms of inflammatory bowel disease (IBD), which is an inflammatory disease. Studies have shown that adipose tissue and inflammation play important roles in the pathogenesis of IBD. C1q/TNF‐related protein‐3 (CTRP3) is a newly discovered adipokine playing a substantial role during inflammatory process, and for the first time in the present study, serum levels of this adipokine were measured in the UC and CD patients. This case–control study included 70 control, 50 UC, and 50 CD patients who were diagnosed by standard criteria. Serum levels of adiponectin, IL‐6, TNF‐α, TGF‐β, and CTRP3 were evaluated using ELISA kits. Serum levels of IL‐6, TNF‐α, and TGF‐β elevated in the UC and CD patients compared with the controls while adiponectin and CTRP3 diminished in the patient's groups compared with the control. Furthermore, decrease in CTRP3 serum levels was associated with the risk of UC and CD diseases. Moreover, CTRP3 indicated negative correlation with BMI, FBS, insulin, homeostasis model assessment of insulin resistance, IL‐6, TNF‐α, and TGF‐β and also a positive correlation with adiponectin in both the UC and CD patients. For the first time, the present study demonstrated lower levels of CTRP3 in the UC and CD patients. Decreased serum levels of CTRP3 and its inverse relationship with inflammatory cytokines and TGF‐β levels suggested a possible role for CTRP3 in the pathogenesis of UC and CD diseases. [ABSTRACT FROM AUTHOR]

Interleukin (IL)‐22 is a member of IL‐10 family cytokines with various immunologic functions. As its name implies, IL‐22 is known to be secreted mainly by Th22 cells, a recently discovered lineage of CD4+ T cells. Also, Th17, Th1, natural killer cells, γδT cells, and innate immune cells along with some nonlymphoid cells have been confirmed as secondary cellular sources of IL‐22. Different cell types such as bronchial and intestinal epithelial cells, keratinocytes, hepatocytes, dermal fibroblasts, and tubular epithelial cells are affected by IL‐22. Both pathologic and protective roles have been attributed to IL‐22 in maintaining gut homeostasis and inflammation. According to the latest fast‐growing investigations, IL‐22 is significantly involved in various pathologies including allergic diseases, infection, autoimmunity, and cancer development. Regulating gut immune responses, barrier integrity, and inflammation is dependent on a diverse complex of cytokines and mediators which are secreted by mucosal immune cells. Several investigations have been designed to recognize the role of IL‐22 in gastrointestinal immunity. This article tries to discuss the latest knowledge on this issue and clarify the potential of IL‐22 to be used in the future therapeutic approaches of intestinal disorders including inflammatory bowel diseases and colon cancer. [ABSTRACT FROM AUTHOR]

This work offers a fault-tolerant strategy that uses a combination of a hardware-based and a control-based faulttolerant methods for multilevel (ML) cascaded H-bridge (CHB) converters. The possibility of a switch failure in an ML converter is higher than a conventional inverter due to the increased number of power electronics switches. Although the event of a single switch failure is more likely, nonetheless, the fault tolerant operation of a ML converter with two or more faulty switches needs to be addressed as well. This article first offers a hardware topology that can bypass the faulty H-bridge cell and replace it with an auxiliary cell, in the event of a single switch failure. Then, it enhances the hardware topology with a modulation-based faulttolerant method for the event of more than one defective switch. Using this strategy, the CHB converter will be able to operate with maximum achievable output voltage in the post-fault condition. Experimental results are presented for a seven-level CHB converter for the validation of the theoretical outcomes. [ABSTRACT FROM AUTHOR]

Hearing loss (HL) is the most common birth defect and the most prevalent sensorineural condition worldwide. It is associated with more than 1,000 mutations in at least 90 genes. Mutations of the gap junction beta‐2 protein (GJB2) gene located in the nonsyndromic hearing loss and deafness (DFNB1) locus (chromosome 13q11‐12) are the main causes of autosomal recessive nonsyndromic hearing loss worldwide, but important differences exist between various populations. In the present article, two common mutations of the GJB2 gene are compared for ethnic‐specific allele frequency, their function, and their contribution to genetic HL in different populations. The results indicated that mutations of the GJB2 gene could have arisen during human migration. Updates on the spectrum of mutations clearly show that frequent mutations in the GJB2 gene are consistent with the founder mutation hypothesis. [ABSTRACT FROM AUTHOR]

This study proposes a power electronics interface (PEI) for photovoltaic (PV) applications with a wide range of ancillary services. As the penetration of distributed generation systems is booming, the PEI for renewable energy sources should be capable of providing ancillary services such as reactive power compensation and low‐voltage ride through (LVRT). This study proposes a robust model predictive‐based control strategy for grid‐tied Z‐source inverters (ZSIs) for PV applications with LVRT capability. The proposed system has two operation modes: normal grid condition and grid fault condition modes. In normal grid condition mode, the maximum available power from the PV panels is injected into the grid. In this mode, the system can provide reactive power compensation as a power conditioning unit for ancillary services from DG systems to main ac grid. In case of grid faults, the proposed system changes the behaviour of reactive power injection into the grid for LVRT operation according to the grid requirements. Thus, the proposed controller for ZSI is taking into account both the power quality issues and reactive power injection under abnormal grid conditions. The proposed system operation is verified experimentally, the results demonstrate fast dynamic response, small tracking error in steady‐state, and simple control scheme. [ABSTRACT FROM AUTHOR]

This study presents a power electronics rapid prototyping platform that can be used to implement a wide range of power conversion circuits and systems quickly and inexpensively. The proposed platform features a modular structure, which is consisted of a control board and a power board. The control board includes adjustable signal conditioning circuitry, adjustable gate driving circuits, networking interfaces, and a fast processing unit that can be programmed easily using MATLAB Simulink code generation tools. The power board houses current and voltage sensors and electric sockets that could be used for implementing various power stage circuits. A case study involving the use of the proposed platform for constructing a buck converter is discussed. A cost evaluation of the proposed platform has also been provided. [ABSTRACT FROM AUTHOR]

This study proposes a fault-tolerant scheme for an impedance-sourced cascaded H-bridge (CHB) converter that can fully restore the converter operation to the pre-fault conditions without any hardware intervention. The proposed faulttolerant scheme has three key elements: a new quasi-z-source CHB converter, a modified modulation method for the introduced z-source CHB, and a modified implementation of the fundamental phase shift compensation (FPSC) method. In case of a fault on one of the inverter switches, the proposed fault-tolerant scheme enables the z-source CHB to generate balanced line-to-line voltages with the same amplitude as the pre-fault voltages, while evenly distributing an inevitable voltage stress increase over all converter switches. In this study, first a brief review of CHB converters and the FPSC method is provided. Then the proposed fault-tolerant scheme is introduced. Finally, several experimental results from a prototype converter are provided to validate the operation of the proposed strategy. [ABSTRACT FROM AUTHOR]

Student ratings of instructors and courses are the most common form of ratings in higher education. There are two main uses of this information: to assess teacher performance for use in personnel and program decisions, and to provide faculty members with feedback to improve their teaching. Theoretically, the best criterion for effective teaching is student learning. Other things being equal, students who rated their teachers as effective should have learned more than students who rated their teachers as ineffective. Despite widespread faculty concern, studies have shown that the research productivity, personality, age, teaching experience, race, and gender of the instructor tend to show little or no relationship to students' ratings.

This study of simulation games suggests a process that can be used in selecting simulation games. The steps in this process include identifying the specific skill or combination of skills to be learned or practiced. Searching potential sources to identify candidates, reviewing instructions and support material for SCANS applicability, and testing the best candidates for actual usefulness. Games should also be evaluated for potential modification to the specific needs. One should realize that if the skill to be taught is not program-specific, the simulation game does not need to be program-specific. The instructor should take care to target the true goal of the activity. In searching for a game, educators should be prepared to utilize all available resources.