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With the aim towards lighter and more efficient electrical systems in future aircraft, design of DC/DC converters with high efficiency, power density and improved thermal management becomes necessary. This paper investigates the detailed design of isolated bidirectional DC/DC converters for more electric aircraft (MEA). Use of wide bandgap (WBG) devices to enhance system efficiency is considered. A transformer optimization technique based on switching frequency for different converter topologies is investigated. The control strategy of the discussed configurations are verified in the PLECS simulation environment. Dual active bridge (DAB), input-series output-parallel (ISOP), neutral point clamped (NPC) and active neutral point clamped (ANPC) converters are considered to exploit benefits offered by WBG devices for MEA. A comparison is performed in terms of efficiency, thermal management, power density and electromagnetic interference (EMI). The results indicate that the ANPC converter is better for efficiency, thermal management and power density. The DAB converter showed similar results to the ISOP with the DAB yielding higher efficiency. The NPC and ANPC configurations resulted in the best EMI performance. The NPC converter proved to be the least effective solution with regard to efficiency, thermal management and power density.

Isolated DC-DC converters are considered the building blocks of modern aircraft electrical power networks. The high-frequency transformer utilized in such converters is the major contributor to the size and weight besides the thermal management system. In this paper, an optimization design methodology aims to minimize the transformer core size and improve the converter performance through optimized winding configurations. The transformer core selection is based on optimizing the maximum flux density while considering different magnetic materials and number of cores in parallel. The transformer core is selected for an interleaved winding configuration and to keep the windings current density below a certain limit. The trade-offs between the converter efficiency and core weight in selecting an optimum switching frequency are presented. Multi-layer minimum gradient (MLMG) winding configurations are proposed to eliminate the high-frequency oscillations (HFO) caused by the transformer parasitics. The proposed configurations resulted in a reduction of the intra-winding capacitance by 15 times with 20$\%$ improvement in the transformer volume as compared to a similar conventional double-layers spiral configurations. Numerical simulations are performed in ANSYS Maxwell to validate the proposed design and the developed analytical models. The effect of the different configurations on the converter performance is verified in the PLECS simulation environment. PLECS simulation results are validated experimentally for the conventional and proposed configurations highlighting the improvements on the performance of the converter.

Background: The pandemic situation created an overwhelmed needs for ICU facilities, according to this problem, the need of accurate the management of facilities represents bold. In this study, prognostic risk factors for ICU admission among COVID-19 hospitalized patients were evaluated. Methods: From 22 February to April 20, 2020. Totally,214 COVID-19 patients participated in this study. The included patients were between 18- 80 years old, and the patients who previously admitted for COVID-19 were excluded. The comorbid medical conditions, admission laboratory, demographic data, and first manifestations were analyzed between two groups, including ICU and non-ICU admitted patients. The statistical analysis, univariate and multivariate analysis were afforded. The value of the predictors in risk assessment of ICU admission were estimated. Results: 55 patients (25.7%) were admitted in ICU. The ICU admitted patient’s mortality rate was about 68%. The age was significantly higher among ICU admission group (P=0.03). Admission O2 saturation was significantly lower among ICU admitted patients (P=0.00). The kidney disease and malignancy history were more frequent in ICU-admitted patients (P=0.04, P=0.00). Myalgia was the clinical manifestation that significantly presented more frequent in ICU-admitted patients. INR, CRP, ESR, HB, and Lymphocyte were significantly different between two groups. After multivariable analysis, admission O2 saturation, hematocrit, CRP and myalgia could significantly predict the risk of ICU admission. Furthermore, the value of predictors was estimated in our study. Conclusion: Based on our results, the admission O2 saturation, HCT, CRP levels at first admission and myalgia presentation could be considered as the valuable predictors of ICU admission.

Recently, emerging technologies have assisted the healthcare system in the treatment of a wide range of diseases so considerably that the development of such methods has been regarded as a practical solution to cure many diseases. Accordingly, underestimating the importance of such cyber environments in the medical and healthcare system is not logical, as a combination of such systems with the Metaverse can lead to tremendous applications, particularly after this pandemic, in which the significance of such technologies has been proven. This is why the digital twin of a medical microrobot, which is controlled via a stochastic model predictive controller (MPC) empowered by a system identification based on machine learning (ML), has been rendered in this research. This robot benefits from the technology of magnetic levitation, and the identification approach helps the controller to identify the dynamic of this robot. Considering the size, control system, and specifications of such micro-magnetic mechanisms, it can play an important role in monitoring, drug-delivery, or even some sensitive internal surgeries. Thus, accuracy, robustness, and reliability have been taken into consideration for the design and simulation of this magnetic mechanism. Finally, a second-order statistic noise is added to the plant while the controller is updated by a Kalman filter to deal with this environment. The results prove that the proposed controller will work effectively.

Background and Objective: Therefore, having the knowledge of using medical equipment for nursing is necessary, which requires learning by using the appropriate teaching method during the student period. The aim of this study was to determine the effect of flipped classroom in comparison with the traditional method on the knowledge of using medical equipment in nursing students. Methods: This study is a quasi-experimental study. The sample consisted of 60 nursing students. The data collection tool was a questionnaire to assess students' knowledge in the field of medical equipment. Equipment-related educational content for one group was delivered in the form of lectures and the other group was performed upside down according to the flipped classroom. Data were analyzed using SPSS software version 16. Findings: : Findings showed that the mean score of knowledge of using selected medical equipment in the lecture classroom (18/33±10/39) and the flipped classroom (18/45±7/76) before the class was not significantly different. (p>0.0) The mean score of knowledge of using selected medical equipment was in the lecture classroom (33/75 ±9/51) and the flipped classroom (42/79 ± 6/91) after the class, which was a significant difference. (P

Introduction: Despite the fact that virtual education has been launched for a short time in medical sciences universities, especially Shahid Sadoughi University of Yazd, it is on initial steps. There is still no information available on the possible effects of this course so that we cannot identify the potential obstacles or problems or use its benefits in efficient way. In the present study, the researchers sought to explain the experiences and perspectives of teachers and students by using qualitative approach. Methods: This study was conducted using a qualitative approach and semi-structured interview. The target population for the interview was teachers and students who had experienced such courses at Shahid Sadoughi University of Medical Sciences in 2019. Result: In examining weaknesses in virtual education, four main categories include facilities, equipment, classroom control, inadequate teacher preparation, and student and emotional and cultural issues and eleven subcategories were extracted. Conclusion: With respect to some obstacles in current education and due to the ever-increasing advances in technology, the use of virtual education methods is needed. If the weaknesses in the implementation of this approach, including upgrading of training and skills levels, technical infrastructure and equipment and cultural context, are fulfilled, it would be more successful.

Background and Objectives: Satisfaction with the environment is one of the human aspirations, in the other words, satisfaction is an ideal concept that provides an appropriate context for empowering individuals and socializing them in order to participate and interfere in their affairs and ultimately in the field of social development. In this regard, one of the roles of designers and architects has been to create a suitable relationship between humans and their environment. Therefore, considering the importance of life satisfaction, educational spaces should provide this feeling of satisfaction for their users. One of the main goals of educational spaces is to achieve success and academic achievement, which in order to improve their goals, should create a suitable and quality space in all dimensions to improve the comprehensive skills for students. In order to stimulate students to learn, learning environment must be effective, safe, capable, positive, personalized, and responsive to the needs of students. Therefore, it has been very important to attention to the environment and environmental factors in providing students' satisfaction and ultimately their academic success. For this reason, one of the subsets of behavioral sciences, has been called environmental psychology that addressed on various human behaviors. In this study, the relationship between satisfactions of effective environmental factors with academic success has been considered among students. The purpose of this study was to identify the effective environmental factors of the university on students' academic achievement and then to evaluate the effectiveness of these factors. Methods: The base method in this research is qualitative but for considering to investigate the results the quantitative and qualitative research method has been used. Therefore, library studies and Observational research have been used to discover the relationship between variables. In the quantitative section, two standard questionnaires were prepared among PhD students of architecture in Azad University of Shiraz, both of which had acceptable validity and reliability. A questionnaire was used to measure the students' satisfaction with the environmental factors of the university, and another questionnaire was used to measure the academic achievement of the same students. The statistical population of the study was calculated using Cochran's formula, which included 54 PhD students, and the results of the questionnaires were extracted by performing statistical calculations in SPSS software. Findings:According to the research findings, with increasing level of satisfaction with environmental factors of university, academic achievement also increased and this correlation was about 0.308‌ By calculating the Pearson coefficient, which indicates a significant relationship and indicates individual adjustment with university. Students with a high level of satisfaction with the environmental factors of the university had very good grades and academic performance and students who were dissatisfied with their studies were not very successful. Conclusion: According to the research findings, environmental factors such as light, thermal comfort, spatial proportions, furniture, green space, entrance, accessibility, noise, materials and colors have been studied. Among these factors, the highest level of satisfaction in environmental factors is furniture, spatial proportions and light, and other environmental factors have had a positive effect on the quality and educational efficiency of the university environment. ===================================================================================== COPYRIGHTS ©2020 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers. =====================================================================================

This paper provides an update and overview of the Center for Remote Sensing of Ice Sheets (CReSIS) radars and platforms, including representative results from these systems. CReSIS radar systems operate over a frequency range of 14–38 GHz. Each radar system's specific frequency band is driven by the required depth of signal penetration, measurement resolution, allocated frequency spectra, and antenna operating frequencies (often influenced by aircraft integration). We also highlight recent system advancements and future work, including (1) increasing system bandwidth; (2) miniaturizing radar hardware; and (3) increasing sensitivity. For platform development, we are developing smaller, easier to operate and less expensive unmanned aerial systems. Next-generation platforms will further expand accessibility to scientists with vertical takeoff and landing capabilities.

Introduction: Nurses often work in stressful environments and it is widely accepted that emotions can exert profound effects on the quality of care in hospital settings. Therefore, the impact of emotional intelligence on the performance of nurses has been the focus of numerous studies. The present study aimed to assess the relationship between emotional intelligence and quality of nursing care from the perspectives of patients in hospitals affiliated to Tehran University of medical sciences. Materials and Methods: The current descriptive-analytic cross-sectional study was conducted on nurses and patients in four selected hospitals affiliated to Tehran University of medical sciences in 2016. Sample size was based on sample size formula in nurses with limited population and patients with unlimited population with 95% confidence level. Finally, a total number of 300 nurses and 270 patients were selected. Data collection tools included standardized Emotional Intelligence Questionnaire and Parasuraman Questionnaire (hospital quality assessment). Results: The best score of nurses’ emotional intelligence was reported in the social self- awareness domain (3.9), while the lowest score was detected in self- motivation domain (3.02). In general, it can be concluded that emotional intelligence in nurses was higher than average with 3.2. The results of the present study indicated that there was no significant relationship between emotional intelligence and the quality of nursing care in selected hospitals. Conclusion: As evidenced by the obtained results, there is a significant relationship between some aspects of the quality of hospital services (e.g., sympathy, assurance, and tangible) and emotional intelligence. Nonetheless, a significant relationship was not confirmed between nurses’ emotional intelligence and the quality of hospital services.

Introduction: This study aimed to explore the challenges ofprofessional identity formation at clinical education environmentsfrom the faculty members’ viewpoints.Methods: This is a qualitative study. The population consistedof clinical faculty members of Tehran University of MedicalSciences. In this study, 39 faculty members participated inan in-depth semi-structured interview. To analyze the data,conventional content analysis approach was used. Open codingwas extracted from the participants’ statements that representedtheir experiences. Then, based on their similarities, the codeswere classified. Subcategories were emerged and after arranging,they were classified into categories based on their relationships.Results: Instability of professional commitment, patientcenterednessas the missing loop care and treatment, andinappropriate conductive context were explored as the challengesof professional identity in clinical educational environment.Conclusion: According to the results of the study, the formationof professional identity among the providers is not an easy taskbecause many factors affect the formation of professional identity.Therefore, a comprehensive shift towards forming the professionalidentity at individual and organizational level should be planned.

Introduction. This study aimed to investigate dental students’ clinical reasoning and diagnostic thinking ability by key feature test and “diagnostic thinking inventory” questionnaire. Methods. The present study was a descriptive cross-sectional study. The participants consisted of 61 senior dental students. Clinical reasoning and diagnostic thinking were assessed by key feature tests and the “diagnostic thinking inventory” “DTI” questionnaire, respectively. The “diagnostic thinking inventory” was developed by Bordage et al. in France and consisted of 41 questions on a 6-point Likert scale. The satisfaction of students was assessed through a 10-item questionnaire. Data were analyzed using SPSS 19 with descriptive tests (mean, SD, and percentage), student independent T-test, and Pearson correlation. The significance level was determined at p

BACKGROUND: The teacher must conduct educational responsibilities in the best way by observing the ethical principles to meet students' educational needs. The aim of the study was to investigate the main factors of professionalism among faculty members from the viewpoints of various stakeholders including learners, peers, and educational officials, as well as the components were assessed from the viewpoints of the stakeholders. MATERIALS AND METHODS: This was a descriptive analytical study conducted in two phases. In the first phase, a questionnaire was developed and validated to assess the professional behavior of faculty members. In the second phase, the evaluation of the teachers' professional behavior was done from the viewpoint of various stakeholders, including learners, middle and senior education managers and peers. The participants were faculty members from 10 schools enrolled in the study by census (n = 427). To extract the factors that constitute professional behavior in faculty members, exploratory factor analysis was used. Data were summarized using descriptive indices (mean, standard deviation, and percent). Exploratory factor analysis (EFA) was used to extract the factors that constitute professional behavior in faculty members. Data was analyzed by using SPSS software (version 23.0). RESULTS: In the first phase, the questionnaire with 11 items was developed. The validity and reliability of the tool was confirmed. The mean (SD) of the faculty members' scores was 4.54(±0.34), with a minimum score of 2.33 and a maximum score of 5.00. The highest scores of faculty members were reported in the items of “altruism to colleagues and students” and the lowest scores were related to “feedback seeking and feedback acceptance”. Professional behavior was categorized under two domains: accountability to professional duties and adherence to professional values. Fifty percent of the participants followed the adherence to professional values (P = 0.22), but less than 50% of the individuals followed the adherence to professional duties significantly (P = 0.002). CONCLUSION: The results of the present study showed that adherence to professional duties was low in faculty members. Assessment of individuals' adherence in these two domains showed that faculty members' compliance in the domain of accountability to professional duties was significantly lower.

Background: Reflection has been extensively used in different areas for better thinking about previous experiences and reaching to new behaviors, which leads to an improvement in personal skills and knowledge. Reflection ability is one of the most essential competencies for healthcare professionals and medical students, which is emphasized in several medical courses and references. This ability is improved with practice and repetition. Therefore, reflection in medical education is very important. Thus the aim of the present study was evaluation of reliability and validity of the tool for assessing this skill and determination of reflection ability level of health care management students. Methods: The present descriptive and cross-sectional research, performed in two phases. The study population were 30 students of health care management. In the first phase, after the translation of the questionnaire, the reliability and validity of the questionnaire was determined. In the second phase and for evaluation of reflection ability level in health care management students, the Groningen Reflection Ability Scale questionnaire was completed by students and data analyzed with independent t-test and Pearson correlation statistical tests. Results: The reliability and validity of the questionnaire were confirmed (Cronbach's alpha = 0.73). The reflection ability score of students was 82.13 ± 4.24. After a statistical analysis of data among genders, although the reflection scores of males (83.58 ± 4.37) were higher than females (81.17 ± 3.97), but this difference was not statistically significant (P-value ≥ 0.05). Also, the difference between demographic variables and reflection ability scores was not statistically significant (P-value ≥ 0.05). Conclusion: This study showed that the GRAS questionnaire is a useful tool for assessing the reflection ability and students have medium scores of reflection ability so educational managers should pay serious attention in planning related fields.

Though designing digital circuits using organic electrochemical transistors (OECTs) is promising due to their high performance, inherent large footprint limits adoption. Here, the authors report staggered top-gate OECTs for all-printed integrated circuits with fast switching and small footprint.

Abstract Slippage occurrence has an important roll in stable and robust object grasping and manipulation. However, in majority of prior research on soft finger manipulation, presence of the slippage between fingers and objects has been ignored. In this paper which is a continuation of our prior work, a revised and more general method for dynamic modeling of planar slippage is presented using the concept of friction limit surface. Friction limit surface is utilized to relate contact sliding motions to contact frictional force and moment in a planar contact. In this method, different states of planar contact are replaced with a second-order differential equation. As an example of the proposed method application, dynamic modeling and slippage analysis of object manipulation on a horizontal plane using a three-link soft finger is studied. Then, a controller is designed to reduce and remove the undesired slippage which occurs between the soft finger and object and simultaneously move the object on a predefined desired path. Numerical simulations reveal the acceptable performance of the proposed method and the designed controller.

Royal jelly, propolis, and bee pollen are used for different purposes all around the world according to their anti-inflammatory, antioxidant, and antimicrobial activities. Given that Coronavirus 2019 (COVID-19) is a viral condition accompanied by a dysregulated inflammatory response in the body, we intend to evaluate the effects of natural supplementations on the disease course. A randomized, open-label, controlled trial was conducted among 50 definitive cases of COVID-19. These patients were randomly assigned into control and intervention groups. Royal Jelly, propolis, and bee pollen were prescribed to patients in the intervention group (n = 24) in addition to conventional treatment; while the control group only received the standard treatment (n = 26). At the end of the study, functional class improved in both groups, but this change was more pronounced in the intervention group (p < 0.05). Moreover, total symptoms duration and the time to return to work were significantly reduced in the intervention group (p < 0.05). Although royal jelly, propolis, and bee pollen are not definitive treatments in COVID-19 patients, they can be used as an adjuvant treatment to limit disease symptoms and virus propagation.

The rapid increase in urbanisation and population growth living in urban areas leads to major problems including increased rates of air pollution and global warming. Assessing the impact of buildings on wind flow, air temperature and pollution dispersion on people at the pedestrian level is, therefore, of crucial importance for urban design. In this study, the effect of different forms of urban vegetation including green roofs, green walls and trees on velocity, air temperature and air quality is assessed using computational fluid dynamics (CFD) for a selected area of the East Village. This study indicates that adding a building increases air temperature, pollution concentration and velocity at the pedestrian level. A parametric analysis is conducted to assess the impact of various key parameters on air temperature, pollution and velocity at the pedestrian level. The variables under consideration include wind speed, ranging from 4–8 m/s at a reference height of 10 m, and vegetation cooling intensity, ranging from 250–500 W·m−3. Three scenarios are tested in which the streets have no bottom heating, 2 °C bottom heating and 10 °C bottom heating. Pollution is simulated as a form of passive scalar with an emission rate of 100 ppb s−1, considering NO2 as the pollutant. In all cases, vegetation is found to reduce air velocity, pollutant concentration and temperature. However, the presence of vegetation in various forms alters the pattern of pollution dispersion differently. More specifically, the results indicate that planting trees (e.g., birch trees) close to the edge of buildings can decrease the air temperature by up to 2–3 °C at the pedestrian level. Increasing the cooling intensity of the vegetation from 250 to 500 W·m−3 results in significantly lower air temperature, whereas lower wind speeds result in a higher concentration of pollutants at the pedestrian level. A combination of green walls and trees is found to be the most effective strategy to improve the thermal environment and air quality.

Background: Kinematic patterns of knees after total knee arthroplasty (TKA) are different from those of healthy knees. We hypothesised that these changes cause a relevant shift in the medial and lateral epicondyles and, consequently, the insertion sites of the collateral ligaments. Any alterations, however, violate the law of Burmester, which states a close relation between the course of the collateral and cruciate ligaments, and the articular surfaces. Methods: Ten healthy knees of whole body cadavers were investigated. The positions of the medial and lateral epicondyles in relation to the tibia were compared before and after cruciate retaining fixed bearing TKA between 0 and 90° of flexion using a navigational device. Results: After TKA, the medial and lateral epicondyles significantly shifted laterally (~3–5mm) between 0° and 40° of flexion. Additionally, the lateral epicondyle was located significantly more dorsal (~3–5mm) during 0° and 20° of flexion and significantly shifted proximally (~2.5–3mm) between 0° and 30° of flexion. Conclusions: By changing the epicondylar positions relative to the articular surfaces, the law of Burmester is violated in the present study setting. This might explain the impairment in motion, instability, or mid-flexion instability and the persistent pain in the knees after TKA.