ABSTRACT
The efficiency of double-junction CIGS/Perovskite-based solar cells has significantly improved through recent research. This study presents a new plasmonic structure for these optical devices, utilizing cluster nanostructures to increase photon absorption between 650 and 1137 nm wavelength ranges. The proposed nanostructure includes two vertically coupled silver nanoparticles embedded at the center of the bottom active layer (CIGS) that absorb most of the incoming light to CIGS within the active layer. The electric field produced by the coupling of the nanoparticles has a superior performance. To analyze the effect of nanoparticle coupling on CIGS/Perovskite solar cell performance, evaluated the short-circuit current density and power conversion efficiency for single and cluster nanostructures with a single nanoparticle in the middle of CIGS. The structures with a single nanoparticle displayed Jsc = 16.89 mA cm-2 and PCE = 31.76%, while the cluster nanostructure represents Jsc = 19 mA cm-2 and PCE = 35.81%. Not only did the use of the cluster nanostructure significantly improve absorption and performance compared to the bare case, but it also exhibited a suitable improvement compared to the single nanoparticle.
ABSTRACT
Here, the influence of dimensional parameters of the trench metal grating on the absorption efficiency of organic solar cells (OSCs) was evaluated. The plasmonic modes were calculated. Due to the capacitance-like charge distribution in a plasmonic configuration, the platform width of grating has a significant influence on the intensity of wedge plasmon polaritons (WPPs) and Gap surface plasmon (GSPs). Stopped-trench gratings would lead to better absorption efficiency than thorough-trenched gratings. The stopped-trench gratings (STG) model with a coating layer showed 77.01% integrated absorption efficiency, which is 19.6% better than previously reported works with 19% less photoactive materials. This model offered 18% integrated absorption efficiency, better than an equivalent planar structure without a coating layer. Specifying the areas with maximum generation on the structure helps us to manage and reduce the thickness and volume of the active layer to control the recombination losses and the cost. We rounded the edges and corners with a curvature radius of 30 nm to investigate tolerance during fabrication. Results demonstrated that the integrated absorption efficiency profile of the blunt model is slightly different from the integrated absorption efficiency profile of the sharp model. Finally, we have studied the wave impedance (Zx) inside the structure. Between the spectrum of λ =â¼700 nm to λ=900 nm, an extremely high wave impedance layer was formed. It creates an impedance mismatch between layers and helps us to better trap the incident light ray. STG with a coating layer (STGC) is a promising way to produce OCSs with extremely thin active layers.
ABSTRACT
Background: Empathetic communication improves the physician-patient relationship and enhances patient and physician satisfaction. This study aims to evaluate the impact of empathic communication skills training on physicians' self-perceived performance and patient satisfaction regarding the empathetic quality of their relationship with their physicians. Methods: In this single-group before-after experimental study, we recruited 50 internal medicine residents at a large teaching hospital. We assessed the residents' empathy using the Jefferson Scale of Empathy before and 3 weeks after an 8-hour workshop on empathic communication skills. We also recruited 50 of their patients before and another 50 patients 3 weeks after the training to assess the patient's perceptions of their physician's empathy using the Consultation and Relational Empathy scale. Physicians' and patients' mean scores on empathetic care at the beginning of the study were then compared using paired t-tests with their scores after the workshop. Results: The residents' mean score on Jefferson Empathy Scale increased from 81.1(95%CI:78.8-83.3) at baseline to 96.8(95%CI:93.6-100) following the workshop (p < 0.001). Before the empathetic communication skills training, patients assessed their doctors' empathy at 68.3(95%CI:63.5-73.2). After the intervention, this improved to 84.9(95%CI:82.2-87.5) (p < 0.001). Conclusion: In this study, both the residents and their patients stated that the residents' empathy skills had significantly improved after an empathetic communication workshop for internal medicine residents.
ABSTRACT
OBJECTIVE: To compare medical students' perceptions regarding Objectively Structured Clinical Examination (OSCE) with Multiple Choice Questions (MCQ) and Oral exam in their semiology course. METHODS: We used a questionnaire with 10 questions regarding the quality of exam (Likert scale) and 3 questions regarding the difficulty, being educative and with descriptive scales. The study carried out in the Centre for Clinical skills located at Firozgar Teaching Hospital affiliated to Iran University of Medical Science. RESULTS: Seventy-three students (65% female) completed the questionnaire. The results of the study showed that exam was very stressful for 63% of participants. Seventy percent believed that OSCE was easier in comparison to MCQ and Oral. About fifty percent (50%) stated that the time was enough. Majority of students expressed that performing the skills at each station was interesting and educative. OSCE, MCQ and ORAL examination were perceived easy by 52.5, 57.9 and 21.1% students respectively. OSCE, MCQ and oral examination were considered educative by 73%, 20% and 56.9% respectively, and fair by 68.9%, 41.4% and 40.7% respectively. CONCLUSION: The findings of this study support OSCE as an acceptable method to assess essentials of practical clinical skills of medical students.
