OSCE Performance Research Articles

Highly efficient organic solar cells enabled by suppressing triplet exciton formation and non-radiative recombination

The high non-radiative energy loss is a bottleneck issue that impedes the improvement of organic solar cells. The formation of triplet exciton is thought to be the main source of the large non-radiative energy loss. Decreasing the rate of back charge transfer is considered as an effective approach to alleviate the relaxation of the charge-transfer state and the triplet exciton generation. Herein, we develops an efficient ternary system based on D18:N3-BO:F-BTA3 by regulating the charge-transfer state disorder and the rate of back charge transfer of the blend. With the addition of F-BTA3, a well-defined morphology with a more condensed molecular packing is obtained. Moreover, a reduced charge-transfer state disorder is demonstrated in the ternary blend, which decreases the rate of back charge transfer as well as the triplet exciton formation, and therefore hinders the non-radiative recombination pathways. Consequently, D18:N3-BO:F-BTA3-based device produces a low non-radiative energy loss of 0.183 eV and a record-high efficiency of 20.25%. This work not only points towards the significant role of the charge-transfer state disorder on the suppression of triplet exciton formation and the non-radiative energy loss, but also provides a valuable insight for enhancing the performance of OSCs.

Does learning style influence performance in objective structured clinical examinations?

BackgroundObjective Structured Clinical Examinations (OSCEs) aim to assess medical students’ clinical skills rather than just their theoretical knowledge. We propose a study between the learning style of second-cycle medical students and their performance in OSCEs.MethodsDuring their internship at our hospital, students were invited to complete the LSQ-Fa, a questionnaire designed to identify their preferences among 4 learning styles: active, reflective, theoretical, and pragmatic. In parallel, an evaluation of their clinical skills was conducted through OSCEs. We then performed an analysis to establish a correlation between learning styles and OSCE performance, to better understand how learning preferences influence academic outcomes.ResultsBetween April 2021 and January 2023, 55 students were evaluated by OSCEs and had completed the LSQ-Fa. The average OSCE score was 14.8/20. The theoretical learning style was predominant in 47.3% of students, followed by active (27.3%), reflective (14.6%), and pragmatic (5.4%), with 3 cases of mixed active and theoretical styles (5.4%). No significant correlation was observed between learning style and OSCE performance (p = 0.28), although students with a pragmatic style recorded a slightly higher average.ConclusionThis study highlights the importance of considering diverse learning styles in the design of medical education programs.

Recent Progress and Applications of NanoIR‐AFM in Morphological Characterization of Organic Solar Cells

AbstractOrganic solar cells (OSCs) are gaining attention in building‐integrated and agricultural photovoltaics due to their light weight, mechanical flexibility, and low‐cost solution processability. To achieve commercial viability, understanding the relationships between active layer material structure, film morphology, and photovoltaic performance is crucial. Nanoscale infrared spectroscopy coupled with atomic force microscopy (nanoIR‐AFM) offers an advanced characterization of active layer morphology at high resolution to help understand OSC performance. This review outlines recent developments and applications of nanoIR‐AFM in OSC research, detailing its principles, instruments, and functions. Strategies to enhance OSC performance and their morphological characterization by nanoIR‐AFM are discussed, offering insights into active layer evolution and device performance. The review highlights challenges faced by nanoIR‐AFM in OSC applications and highlights its potential role in advancing OSC technology. As nanoIR‐AFM continues to evolve, it will play a critical role in OSC development, providing essential technical means for further progress.

A case-controlled trial evaluating the summative performance of the 3-D skills Model

BackgroundNear-peer teaching is a popular pedagogical teaching tool however many existing models fail to demonstrate benefits in summative OSCE performance. The 3-step deconstructed (3-D)skills near-peer model was recently piloted in undergraduate medicine showing short term improvement in formative OSCE performance utilising social constructivist educational principles. This study aims to assess if 3-D skills model teaching affects summative OSCE grades.MethodsSeventy-nine third year medical students attended a formative OSCE event at the University of Glasgow receiving an additional 3-minutes per station of either 3-D skills teaching or time-equivalent unguided practice. Students’ summative OSCE results were compared against the year cohort to establish whether there was any difference in time delayed summative OSCE performance.Results3-D skills and unguided practice cohorts had comparable demographical data and baseline formative OSCE performance. Both the 3-D skill cohort and unguided practice cohort achieved significantly higher median station pass rates at summative OSCEs than the rest of the year. This correlated to one additional station pass in the 3-D skills cohort, which would increase median grade banding from B to A. The improvement in the unguided practice cohort did not achieve educational significance.ConclusionIncorporating the 3-D skills model into a formative OSCE is associated with significantly improved performance at summative OSCEs. This expands on the conflicting literature for formative OSCE sessions which have shown mixed translation to summative performance and suggests merit in institutional investment to improve clinical examination skills.

Tailoring support following summative assessments: a latent profile analysis of student outcomes across five medical specialities.

Summative assessments are often underused for feedback, despite them being rich with data of students' applied knowledge and clinical and professional skills. To better inform teaching and student support, this study aims to gain insights from summative assessments through profiling students' performance patterns and identify those students missing the basic knowledge and skills in medical specialities essential for their future career. We use Latent Profile Analysis to classify a senior undergraduate year group (n = 295) based on their performance in applied knowledge test (AKT) and OSCE, in which items and stations are pre-classified across five specialities (e.g. Acute and Critical Care, Paediatrics,…). Four distinct groups of students with increasing average performance levels in the AKT, and three such groups in the OSCE are identified. Overall, these two classifications are positively correlated. However, some students do well in one assessment format but not in the other. Importantly, in both the AKT and the OSCE there is a mixed group containing students who have met the required standard to pass, and those who have not. This suggests that a conception of a borderline group at the exam-level can be overly simplistic. There is little literature relating AKT and OSCE performance in this way, and the paper discusses how our analysis gives placement tutors key insights into providing tailored support for distinct student groups needing remediation. It also gives additional information to assessment writers about the performance and difficulty of their assessment items/stations, and to wider faculty about student overall performance and across specialities.

Synergistic charge-transfer dynamics of rigid fused and unfused backbone with donors lead to promising photovoltaic properties of diazaborinine-based chromophores

Herein, a series of diazaborinin based derivatives (FABD1–FABD8) having D-π-D configuration was designed by inserting different types of rigid fused and unfused π-bridges into reference molecule (FABR) to explore their photovoltaic characteristics. To determine the optoelectronic and charge transport characteristics of these analogues, DFT/TD-DFT based calculations were conducted at the MPW1PW91/6-31G (d,p) level. For this, various analyses were performed such as transition density matrix (TDM), global reactivity parameters (GRP), open-circuit voltage (Voc), optical properties (UV–Vis), binding energy (Eb), hole-electron and frontier molecular orbital (FMO) energies. Their insights indicate that a rigid fused π-bridge greatly lowers the band gap as compared to an unfused π-spacers. Particularly, FABD7 showed the lowest energy gap of 2.20 eV owing to the presence of a rigid fused central core as compared to FABR with a band gap of 2.65 eV. Similarly, the entitled designed derivatives demonstrated a redshift absorption in the range of 585.7–704.6 nm while FABR is reported with 558.7 nm in the solvent phase. Furthermore, these derivatives displayed significant Voc with blending of PC61BM acceptor. This observation was also supported by DOS and TDM based insights. Interestingly, FABD7 seemed as a viable photovoltaic material due to its strong optical properties and small band gaps. These results uncover that the designed chromophores may be considered as efficient to enhance the performance of OSCs.

Increasing terminal alkyl chain length for a better small molecule organic solar cell donor

Optimizing the alkyl chains within a terminal group is considered to be a highly effective approach for boosting the power conversion efficiency (PCE) of all small-molecule organic solar cells (ASM-OSCs). In this study, we focus on designing and synthesizing small molecular (SM) donor compounds with different end-group alkyl chain lengths to study their impact on OSC performance. Under optimized conditions, OSC devices based on BTR-Cl-C8:Y6 demonstrate higher PCE of 14.43 % compared to those based on BTR-Cl:Y6. Moreover, BTR-Cl-C8 exhibits reduced levels of bimolecular recombination and trap-assisted recombination, enhanced capability for exciton dissociation and charge collection, and extended carrier lifetimes. These results highlight the significance of molecular design strategies in optimizing OSC performance and offer valuable insights for the development of efficient and stable ASM-OSCs.

Ethylenedioxythiophene‐Based Small Molecular Donor with Multiple Conformation Locks for Organic Solar Cells with Efficiency of 19.3 %

AbstractTernary organic solar cells (T‐OSCs) represent an efficient strategy for enhancing the performance of OSCs. Presently, the majority of high‐performance T‐OSCs incorporates well‐established Y‐acceptors or donor polymers as the third component. In this study, a novel class of conjugated small molecules has been introduced as the third component, demonstrating exceptional photovoltaic performance in T‐OSCs. This innovative molecule comprises ethylenedioxythiophene (EDOT) bridge and 3‐ethylrhodanine as the end group, with the EDOT unit facilitating the creation of multiple conformation locks. Consequently, the EDOT‐based molecule exhibits two‐dimensional charge transport, distinguishing it from the thiophene‐bridged small molecule, which displays fewer conformation locks and provides one‐dimensional charge transport. Furthermore, the robust electron‐donating nature of EDOT imparts the small molecule with cascade energy levels relative to the electron donor and acceptor. As a result, OSCs incorporating the EDOT‐based small molecule as the third component demonstrate enhanced mobilities, yielding a remarkable efficiency of 19.3 %, surpassing the efficiency of 18.7 % observed for OSCs incorporating thiophene‐based small molecule as the third component. The investigations in this study underscore the excellence of EDOT as a building block for constructing conjugated materials with multiple conformation locks and high charge carrier mobilities, thereby contributing to elevated photovoltaic performance in OSCs.

Ethylenedioxythiophene-Based Small Molecular Donor with Multiple Conformation Locks for Organic Solar Cells with Efficiency of 19.3 .

Ternary organic solar cells (T-OSCs) represent an efficient strategy for enhancing the performance of OSCs. Presently, the majority of high-performance T-OSCs incorporates well-established Y-acceptors or donor polymers as the third component. In this study, a novel class of conjugated small molecules has been introduced as the third component, demonstrating exceptional photovoltaic performance in T-OSCs. This innovative molecule comprises ethylenedioxythiophene (EDOT) bridge and 3-ethylrhodanine as the end group, with the EDOT unit facilitating the creation of multiple conformation locks. Consequently, the EDOT-based molecule exhibits two-dimensional charge transport, distinguishing it from the thiophene-bridged small molecule, which displays fewer conformation locks and provides one-dimensional charge transport. Furthermore, the robust electron-donating nature of EDOT imparts the small molecule with cascade energy levels relative to the electron donor and acceptor. As a result, OSCs incorporating the EDOT-based small molecule as the third component demonstrate enhanced mobilities, yielding a remarkable efficiency of 19.3 %, surpassing the efficiency of 18.7 % observed for OSCs incorporating thiophene-based small molecule as the third component. The investigations in this study underscore the excellence of EDOT as a building block for constructing conjugated materials with multiple conformation locks and high charge carrier mobilities, thereby contributing to elevated photovoltaic performance in OSCs.

Advances in anode interfacial materials for organic solar cells

AbstractOrganic solar cells (OSCs) have attracted much interest in the past few decades because of their advantages, such as being lightweight, low cost, simple preparation process, and environmental friendliness. While researchers have made significant progress on the active layer materials of OSCs, the interface engineering is another entry point for upgrading the photovoltaic performance of OSCs. Significantly, the interface modification materials, including anode interfacial materials and cathode interfacial materials, are two essential parts of interfacial layers for OSCs, in which the excellent interfacial materials can realize the very high‐performance photovoltaic cells. Among these interfacial materials, the anode interfacial layers (AILs) play a crucial role in improving photovoltaic performance. This review expresses a detailed conclusion of the development of anode interfacial materials and an outlook on future trends for OSCs.

Guidelines for Material Design in Semitransparent Organic Solar Cells

AbstractOrganic solar cells (OSCs) are uniquely suited for semitransparent applications due to their adjustable absorption spectrum. However, most high‐performance semitransparent cells reported to date are based on materials that have shown high power conversion efficiency for opaque devices. A model is therefore presented to assess the optimum efficiency and transparency for a specific donor and acceptor bandgap. The absorption characteristics of both donor and acceptor are modeled with spectral data of typical absorber materials from the literature which are adjusted to achieve the desired bandgap value. The results show three distinct regions of high light utilization efficiency (LUE) if the photopic curve is employed as a weighting function (corresponding to window applications), and a broad maximum for the plant action spectrum as a weighting function (corresponding to greenhouse applications). When comparing these findings to reported experimental values, it is evident that the bandgaps of the materials used for the experimental studies do not correspond to the maxima identified by the simulation model. The analysis of the energy levels of molecules recorded in the literature confirms that all bandgaps and therefore all LUE maxima are chemically feasible so that the performance of semitransparent OSCs can be further improved by designing materials with optimized absorption spectra.

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The incorporation of DBrB solid additive leads to the formation of a 3D interpenetrating network and an orderly arrangement of photoactive materials processed from halogen‐free solvent. The DBrB‐processed OSC based on PM6:Y6‐HU achieves the highest PCE of 18.6% and FF of 79.0% among the currently reported non‐halogenated‐processed binary devices. This strategy provides a valuable information for enhancing the photovoltaic performance of OSCs. image

Recent advances in effect of crystallization dynamics process on the morphology of active layer in organic solar cells

AbstractOrganic solar cells (OSCs) have received widespread attention due to their light weight, low cost, semitransparency, and ease‐of‐solution processing. By continuously improving materials design, active layer morphology, and device fabrication techniques, the power conversion efficiency (PCE) of OSCs have exceeded 20%. The morphology of the active layer, which includes the phase separation structure, the degree of crystallinity of molecules, and the domain sizes, plays a critically important role in the performance, which is significantly influenced by the crystallization dynamics of the donor and acceptor. Therefore, it is crucial to comprehensively understand how the dynamics impact the film structure and how to effectively employ the kinetic procedure to enhance the structure of the active layer in OSCs. In this review, the methods and principles of kinetics characterization were introduced. Afterward, the latest advancements in the control of film‐forming and the post annealing process are outlined, unveiling the underlying mechanism. In conclusion, the potential and future of OSCs were anticipated and projected. Researchers may gain a comprehensive understanding of how dynamic process affects the morphology through this review, potentially enhancing the performance of OSCs.

Impact of familiarity with the format of the exam on performance in the OSCE of undergraduate medical students – an interventional study

BackgroundAssessments, such as summative structured examinations, aim to verify whether students have acquired the necessary competencies. It is important to familiarize students with the examination format prior to the assessment to ensure that true competency is measured. However, it is unclear whether students can demonstrate their true potential or possibly perform less effectively due to the unfamiliar examination format. Hence, we questioned whether a 10-min active familiarization in the form of simulation improved medical students´ OSCE performance. Next, we wanted to elucidate whether the effect depends on whether the familiarization procedure is active or passive.MethodsWe implemented an intervention consisting of a 10-min active simulation to prepare the students for the OSCE setting. We compared the impact of this intervention on performance to no intervention in 5th-year medical students (n = 1284) from 2018 until 2022. Recently, a passive lecture, in which the OSCE setting is explained without active participation of the students, was introduced as a comparator group. Students who participated in neither the intervention nor the passive lecture group formed the control group. The OSCE performance between the groups and the impact of gender was assessed using X2, nonparametric tests and regression analysis (total n = 362).ResultsWe found that active familiarization of students (n = 188) yields significantly better performance compared to the passive comparator (Cohen´s d = 0.857, p < 0.001, n = 52) and control group (Cohen´s d = 0.473, p < 0.001, n = 122). In multivariate regression analysis, active intervention remained the only significant variable with a 2.945-fold increase in the probability of passing the exam (p = 0.018).ConclusionsA short 10-min active intervention to familiarize students with the OSCE setting significantly improved student performance. We suggest that curricula should include simulations on the exam setting in addition to courses that increase knowledge or skills to mitigate the negative effect of nonfamiliarity with the OSCE exam setting on the students.

Constructing efficient organic solar cells by highly volatile solid additives with controlled phase morphology.

We synthesized two highly volatile and low-cost solid additives, PT and TFT. The inclusion of PT and TFT effectively influences the aggregation behavior of D18: L8-BO during the film-forming process. Consequently, PT and TFT-treated D18: L8-BO-based OSCs achieved power conversion efficiencies of 18.28% and 19.19%, respectively. This study provides a straightforward approach for achieving efficient photovoltaic performance of OSCs.

Powering the Future: A Critical Review of Research Progress in Enhancing Stability of High‐Efficiency Organic Solar Cells

AbstractOrganic solar cells (OSCs) are a promising photovoltaic technology that employs organic semiconductor material as the photoactive layer, which has the unique advantages of light weight, large‐area flexible fabrication, low‐cost, and semitransparent. In recent years, the performance of OSCs has been significantly improved, and the highest power conversion efficiency has exceeded 19%. Despite the tremendous progress in OSCs, the major bottleneck in realizing the commercialization of OSCs is the device stability. Therefore, reviewing the recent research progress on the stability of high‐performance OSCs is urgent and necessary. This review discusses the factors limiting device lifetime, such as metastable morphology, air, irradiation, heat, and mechanical stresses. Additionally, this review presents the research progress over the last 5 years, focusing on enhancing device stability from the perspective of photoactive layers and other functional layers, which includes material design and device engineering, such as solid additives, device fabrication, optimizing buffer layers, using stable electrodes, and encapsulation. Lastly, this review explores current commercialization challenges and prospects, including using advanced machine learning techniques to assist experimental research.

Corrélation entre les notes obtenues aux ECOS et aux épreuves de connaissances et analyse des facteurs associés à une meilleure réussite aux ECOS chez les étudiants de DFASM1 et 2 au CHU de Dijon

RationaleObjective structured clinical examinations (OSCEs) were introduced to evaluate students not only on their knowledge, but also on their clinical skills and attitudes. The objectives were to study the correlation between OSCE scores and scores obtained to traditional knowledge examinations and to analyse factors associated with better OSCE performance in DFASM1 and 2 students at Dijon university hospital. MethodsThis was a prospective observational study conducted among all fourth and fifth year medical students in Dijon. The scores on the OSCE elective tests (2022) and the average score on the knowledge tests (2021–2022) were collected and their correlation measured. A questionnaire asked students about their demographic characteristics, their investment in formative and practicum OSCEs, their level of empathy (Jefferson questionnaire) and their personality traits (NEO-Pi-R). ResultsOf 549 students, 513 completed all tests. Scores on OSCE and faculty knowledge tests were correlated (r=0.39, P<0.001). Of these, 111 (20%) students responded to the questionnaire, and 97 were analized. We did not observe any significant difference between students who performed better on OSCEs than on knowledge tests and those who did not, regarding their age, their investment in formative tests, their personality traits or their level of empathy. ConclusionOur results underline the need to optimize the evaluation of empathy and clinical skills in OSCE tests, using new tools, in order to better discriminate between students on these skills.

Evaluating the Effectiveness of the SPIKES Model to Break Bad News - A Systematic Review.

Introduction: Breaking bad news to patients and families can be challenging for healthcare providers. The present study conducted a systematic review of the literature to determine if formal communication training using the SPIKES protocol improves learner satisfaction, knowledge, performance, or system outcomes. Method: MEDLINE, Embase, CINAHL Plus (Nursing & Allied Health Sciences), and PsycINFO Databases were searched with keywords BAD NEWS and SPIKES. Studies were required to have an intervention using the SPIKES model and an outcome that addressed at least one of the four domains of the Kirkpatrick model for evaluating training effectiveness. The Cochrane Risk of Bias Tool was used to conduct a risk of bias assessment. Due to heterogeneity in the interventions and outcomes, meta-analysis was not undertaken and instead, a narrative synthesis was used with the information provided in the tables to summarise the main findings of the included studies. Results: Of 622 studies screened, 37 publications met the inclusion criteria. Interventions ranged from the use of didactic lecture, role play with standardised patients (SPs), video use, debriefing sessions, and computer simulations. Evaluation tools ranged from pre and post intervention questionnaires, OSCE performance with rating by independent raters and SPs, and reflective essay writing. Conclusions: Our systematic review demonstrated that the SPIKES protocol is associated with improved learner satisfaction, knowledge and performance. None of the studies in our review examined system outcomes. As such, further educational development and research is needed to evaluate the impact of patient outcomes, including the optimal components and length of intervention.

High-Performance Ternary Organic Solar Cells Enabled by Introducing a New A-DA'D-A Guest Acceptor with Higher-Lying LUMO Level.

A ternary strategy is viable to minimize the trade-off between short-circuit current density (Jsc) and open-circuit voltage (Voc) in organic solar cells. Generally, the ternary OSCs can achieve a higher PCE than the binary counterparts by subtly utilizing the particular photoelectric properties of the third material. In this regard, we choose BTP-CC with a higher-lying LUMO level based on a fused TPBT (dithienothiophen[3.2-b]-pyrrolobenzothiadiazole) central framework and CC (2-(6-oxo-5,6-dihydro-4H-cyclopenta [b]thiophen-4-ylidene) malononitrile) flanking groups as the third component to broaden the light-absorption spectrum, regulate the bulk heterojunction (BHJ) morphology, improve the Voc, and reduce the charge recombination in OSCs. In addition, BTP-CC demonstrates intense intermolecular energy transfer to Y6 by fluorescence resonance energy transfer (FRET) pathway, which is due to the photoluminescence (PL) spectrum of BTP-CC covering the absorption region of Y6. The PM6:Y6:BTP-CC based ternary OSC achieves a champion PCE of 17.55%. Further investigation indicates that introduction of BTP-CC could reduce the trap states in OSCs, leading to an increased charge carrier density. Moreover, the incorporation of BTP-CC could improve the device stability. These results demonstrated that BTP-CC is important in improving the photovoltaic performance of ternary OSCs, and this work also provides a guideline for constructing ideal ternary OSCs in the future.

Novel Third Components with (Thio)barbituric Acid as the End Groups Improving the Efficiency of Ternary Solar Cells.

Developing novel third component is critical for the ternary organic solar cells (TOSCs). Herein, we design and synthesize two novel third components, MAZ-1 and MAZ-2, with 1,3-diethyl-2-thiobarbituric acid and 1,3-dimethylbarbituric acid as the weak electron withdrawing end groups, respectively. Both MAZ-1 and MAZ-2 could improve the photovoltaic performance of the binary OSCs based on D18:Y6 which exhibit the power conversion efficiency (PCE) of 17%, because the third components can optimize the phase separation, suppress the bimolecular recombination, and decrease the nonradiative energy loss in ternary blends. The PCE of the optimized TOSCs approaches 18% along with the simultaneous increase in open circuit voltage, short circuit current density, and fill factor by incorporating 10 wt % MAZ-1 and MAZ-2 in acceptors. This work enriches the building blocks for novel third components for achieving highly efficient TOSCs.