The Dental School Interview As a Predictor of Dental Students' OSCE Performance.

PubMed

Park, Sang E; Price, Mirissa D; Karimbux, Nadeem Y

2018-03-01

The aim of this study was to evaluate the use of the dental school admissions interview score as a noncognitive indicator of performance in predoctoral dental education, with specific attention to whether a correlation existed between the admissions interview scores and performance on the objective structured clinical examination (OSCE). The study population consisted of all 175 students in the Harvard School of Dental Medicine (HSDM) DMD Classes of 2012 through 2016. Data on students' gender and age on entering dental school were self-reported using their applications for admission to the HSDM DMD program. Data on students' OSCE scores for three examination sessions were collected from the Office of Dental Education. The results showed that the students' interview scores did not significantly correlate with OSCE performance on any of the three exams. Performance on the first and second OSCEs did, however, correlate with performance on the third OSCE (p<0.05). Age on entering dental school was not significantly associated with performance on any of the three OSCEs; however, among male students, there was a significant negative correlation (p<0.05) between entering age and performance on the second and third OSCEs. There was no significant association between gender and OSCE or interview score. These results suggest that although the admissions interview scores can serve as an important resource in student selection, with the lack of association between interview and OSCE scores, it is possible that the communication skills required for the interview do not directly overlap with those required for OSCE success.

Evaluating an Objective Structured Clinical Examination (OSCE) Adapted for Social Work

ERIC Educational Resources Information Center

Bogo, Marion; Regehr, Cheryl; Katz, Ellen; Logie, Carmen; Tufford, Lea; Litvack, Andrea

2012-01-01

Objectives: To evaluate an objective structured clinical examination (OSCE) adapted for social work in a lab course and examine the degree to which it predicts competence in the practicum. Method: 125 Masters students participated in a one-scenario OSCE and wrote responses to standardized reflection questions. OSCE performance and reflections were…

Influences of OSCE design on students' diagnostic reasoning.

PubMed

Lafleur, Alexandre; Côté, Luc; Leppink, Jimmie

2015-02-01

Some characteristics of assessments exert a strong influence on how students study. Understanding these pre-assessment learning effects is of key importance to the designing of medical assessments that foster students' reasoning abilities. Perceptions of the task demands of an assessment significantly influence students' cognitive processes. However, why and how certain tasks positively 'drive' learning remain unknown. Medical tasks can be assessed as coherent meaningful whole tasks (e.g. examining a patient based on his complaint to find the diagnosis) or can be divided into simpler part tasks (e.g. demonstrating the physical examination of a pre-specified disease). Comparing the benefits of whole-task and part-task assessments in a randomised controlled experiment could guide the design of 'assessments for learning'. The purpose of this study was to determine whether the knowledge that an objective structured clinical examination (OSCE) will contain whole tasks, as opposed to part tasks, increases the use of diagnostic reasoning by medical students when they study for this assessment. In this randomised, controlled, mixed-methods experiment, 40 medical students were randomly paired and filmed while studying together for two imminent physical examination OSCE stations. Each 25-minute study period began with video cues and ended with a questionnaire on cognitive loads. Cues disclosed either a part-task OSCE station (examination of a healthy patient) or a whole-task OSCE station (hypothesis-driven physical examination [HDPE]). In a crossover design, sequences were randomised for both task and content (shoulder or spine). Two blinded and independent authors scored all 40 videos in distinct randomised orders, listening to participants studying freely. Mentioning a diagnosis in association with a sign was scored as a backward association, and the opposite was scored as a forward association; both revealed the use of diagnostic reasoning. Qualitative data were obtained

Enhancing OSCE preparedness with video exemplars in undergraduate nursing students. A mixed method study.

PubMed

Massey, D; Byrne, J; Higgins, N; Weeks, B; Shuker, M-A; Coyne, E; Mitchell, M; Johnston, A N B

2017-07-01

Objective structured clinical examinations (OSCEs) are designed to assess clinical skill performance and competency of students in preparation for 'real world' clinical responsibilities. OSCEs are commonly used in health professional education and are typically associated with high levels of student anxiety, which may present a significant barrier to performance. Students, including nursing students, have identified that flexible access to exemplar OSCEs might reduce their anxiety and enable them to better prepare for such examinations. To implement and evaluate an innovative approach to preparing students for OSCEs in an undergraduate (registration) acute care nursing course. A set of digitized OSCE exemplars were prepared and embedded in the University-based course website as part of usual course learning activities. Use of the exemplars was monitored, pre and post OSCE surveys were conducted, and qualitative data were collected to evaluate the approach. OSCE grades were also examined. The online OSCE exemplars increased self-rated student confidence, knowledge, and capacity to prepare and provided clarity around assessment expectations. OSCE exemplars were accessed frequently and positively received; but did not impact on performance. Video exemplars aid student preparation for OSCEs, providing a flexible, innovative and clear example of the assessment process. Video exemplars improved self-rated student confidence and understanding of performance expectations, leading to increased engagement and reduced anxiety when preparing for the OSCE, but not overall OSCE performance. Such OSCE exemplars could be used to increase staff capacity and improve the quality of the student learning experience. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Generalized Optimal-State-Constraint Extended Kalman Filter (OSC-EKF)

DTIC Science & Technology

2017-02-01

ARL-TR-7948• FEB 2017 US Army Research Laboratory GeneralizedOptimal-State-Constraint ExtendedKalman Filter (OSC-EKF) by James M Maley, Kevin...originator. ARL-TR-7948• FEB 2017 US Army Research Laboratory GeneralizedOptimal-State-Constraint ExtendedKalman Filter (OSC-EKF) by James M Maley Weapons and...

In the Minds of OSCE Examiners: Uncovering Hidden Assumptions

ERIC Educational Resources Information Center

Chahine, Saad; Holmes, Bruce; Kowalewski, Zbigniew

2016-01-01

The Objective Structured Clinical Exam (OSCE) is a widely used method of assessment in medical education. Rater cognition has become an important area of inquiry in the medical education assessment literature generally, and in the OSCE literature specifically, because of concerns about potential compromises of validity. In this study, a novel…

Application of best practice guidelines for OSCEs-An Australian evaluation of their feasibility and value.

PubMed

Mitchell, Marion L; Henderson, Amanda; Jeffrey, Carol; Nulty, Duncan; Groves, Michele; Kelly, Michelle; Knight, Sabina; Glover, Pauline

2015-05-01

Objective Structured Clinical Examinations (OSCEs) are widely used in health professional education and should be based on sound pedagogical foundations. The aim of this study is to evaluate the feasibility and utility of using Best Practice Guidelines (BPGs) within an OSCE format in a broad range of tertiary education settings with under-graduate and post-graduate nursing and midwifery students. We evaluated how feasible it was to apply the BPGs to modify OSCEs in a course; students' perspective of the OSCE; and finally, if the BPG-revised OSCEs better prepared students for clinical practice when compared with the original OSCEs. A mixed method with surveys, focus groups and semi-structured interviews evaluated the BPGs within an OSCE. Four maximally different contexts across four sites in Australia were used. Participants included lecturers and undergraduate nursing students in high and low fidelity simulation settings; under-graduate midwifery students; and post-graduate rural and remote area nursing students. 691 students participated in revised OSCEs. Surveys were completed by 557 students; 91 students gave further feedback through focus groups and 14 lecturers participated in interviews. At all sites the BPGs were successfully used to modify and implement OSCEs. Students valued the realistic nature of the modified OSCEs which contributed to students' confidence and preparation for clinical practice. The lecturers considered the revised OSCEs enhanced student preparedness for their clinical placements. The BPGs have a broad applicability to OSCEs in a wide range of educational contexts with improved student outcomes. Students and lecturers identified the revised OSCEs enhanced student preparation for clinical practice. Subsequent examination of the BPGs saw further refinement to a set of eight BPGs that provide a sequential guide to their application in a way that is consistent with best practice curriculum design principles. Copyright © 2015 Elsevier Ltd

Student reflections on learning cross-cultural skills through a 'cultural competence' OSCE.

PubMed

Miller, Elizabeth; Green, Alexander R

2007-05-01

Medical schools use OSCEs (objective structured clinical examinations) to assess students' clinical knowledge and skills, but the use of OSCEs in the teaching and assessment of cross-cultural care has not been well described. To examine medical students' reflections on a cultural competence OSCE station as an educational experience. Students at Harvard Medical School in Boston completed a 'cultural competence' OSCE station (about a patient with uncontrolled hypertension and medication non-adherence). Individual semi-structured interviews were conducted with a convenience sample of twenty-two second year medical students, which were recorded, transcribed, and analysed. Students' reflections on what they learned as the essence of the case encompassed three categories: (1) eliciting the patient's perspective on their illness; (2) examining how and why patients take their medications and inquiring about alternative therapies; and (3) exploring the range of social and cultural factors associated with medication non-adherence. A cultural competence OSCE station that focuses on eliciting patients' perspectives and exploring medication non-adherence can serve as a unique and valuable teaching tool. The cultural competence OSCE station may be one pedagogic method for incorporating cross-cultural care into medical school curricula.

OSCE as a Summative Assessment Tool for Undergraduate Students of Surgery-Our Experience.

PubMed

Joshi, M K; Srivastava, A K; Ranjan, P; Singhal, M; Dhar, A; Chumber, S; Parshad, R; Seenu, V

2017-12-01

Traditional examination has inherent deficiencies. Objective Structured Clinical Examination (OSCE) is considered as a method of assessment that may overcome many such deficits. OSCE is being increasingly used worldwide in various medical specialities for formative and summative assessment. Although it is being used in various disciplines in our country as well, its use in the stream of general surgery is scarce. We report our experience of assessment of undergraduate students appearing in their pre-professional examination in the subject of general surgery by conducting OSCE. In our experience, OSCE was considered a better assessment tool as compared to the traditional method of examination by both faculty and students and is acceptable to students and faculty alike. Conducting OSCE is feasible for assessment of students of general surgery.

The Associations Between Clerkship Objective Structured Clinical Examination (OSCE) Grades and Subsequent Performance.

PubMed

Dong, Ting; Zahn, Christopher; Saguil, Aaron; Swygert, Kimberly A; Yoon, Michelle; Servey, Jessica; Durning, Steven

2017-01-01

Construct: We investigated the extent of the associations between medical students' clinical competency measured by performance in Objective Structured Clinical Examinations (OSCE) during Obstetrics/Gynecology and Family Medicine clerkships and later performance in both undergraduate and graduate medical education. There is a relative dearth of studies on the correlations between undergraduate OSCE scores and future exam performance within either undergraduate or graduate medical education and almost none on linking these simulated encounters to eventual patient care. Of the research studies that do correlate clerkship OSCE scores with future performance, these often have a small sample size and/or include only 1 clerkship. Students in USU graduating classes of 2007 through 2011 participated in the study. We investigated correlations between clerkship OSCE grades with United States Medical Licensing Examination Step 2 Clinical Knowledge, Clinical Skills, and Step 3 Exams scores as well as Postgraduate Year 1 program director's evaluation scores on Medical Expertise and Professionalism. We also conducted contingency table analysis to examine the associations between poor performance on clerkship OSCEs with failing Step 3 and receiving poor program director ratings. The correlation coefficients were weak between the clerkship OSCE grades and the outcomes. The strongest correlations existed between the clerkship OSCE grades and the Step 2 CS Integrated Clinical Encounter component score, Step 2 Clinical Skills, and Step 3 scores. Contingency table associations between poor performances on both clerkships OSCEs and poor Postgraduate Year 1 Program Director ratings were significant. The results of this study provide additional but limited validity evidence for the use of OSCEs during clinical clerkships given their associations with subsequent performance measures.

Increased Authenticity in Practical Assessment Using Emergency Case OSCE Stations

ERIC Educational Resources Information Center

Ruesseler, Miriam; Weinlich, Michael; Byhahn, Christian; Muller, Michael P.; Junger, Jana; Marzi, Ingo; Walcher, Felix

2010-01-01

In case of an emergency, a fast and structured patient management is crucial for patient's outcome. The competencies needed should be acquired and assessed during medical education. The objective structured clinical examination (OSCE) is a valid and reliable assessment format to evaluate practical skills. However, traditional OSCE stations examine…

Detection Learning Style Vark For Out Of School Children (OSC)

NASA Astrophysics Data System (ADS)

Amran, Ali; Desiani, Anita; Hasibuan, MS

2017-04-01

Learning style is different for every learner especially for out of school children or OSC. They are not like formal students, they are learners but they don’t have a teacher as a guide for learning. E-learning is one of the solutions to help OSC to get education. E-learning should have preferred learning styles of learners. Data for identifying the learning style in this study were collected with a VARK questionnaire from 25 OSC in junior high school level from 5 municipalities in Palembang. The validity of the questionnaire was considered on basis of experts’ views and its reliability was calculated by using Cronbach’s alpha coefficients (α=0.68). Overall, 55% preferred to use a single learning style (Uni-modal). Of these, 27,76% preferred Aural, 20,57% preferred Reading Writing, 33,33% preferred Kinaesthetic and 23,13% preferred Visual. 45% of OSC preferred more than one style, 30% chose two-modes (bimodal), and 15% chose three-modes (tri-modal). The Most preferred Learning style of OSC is kinaesthetic learning. Kinaesthetic learning requires body movements, interactivities, and direct contacts with learning materials, these things can be difficult to implement in eLearning, but E-learning should be able to adopt any learning styles which are flexible in terms of time, period, curriculum, pedagogy, location, and language.

OSCE-based Clinical Skill Education for Physical and Occupational Therapists

PubMed Central

Sakurai, Hiroaki; Kanada, Yoshikiyo; Sugiura, Yoshito; Motoya, Ikuo; Wada, Yosuke; Yamada, Masayuki; Tomita, Masao; Tanabe, Shigeo; Teranishi, Toshio; Tsujimura, Toru; Sawa, Syunji; Okanishi, Tetsuo

2014-01-01

[Purpose] The aim of this study was to examine the applicability of the Objective Structured Clinical Examination (OSCE) to postgraduate education systems for novice and mid-career therapists in workplaces. [Subjects] Physical and occupational therapists with 1 to 5 years of clinical experience took the OSCE to assess their learning, with a physical or occupational therapy faculty member and a clinical supervisor as examiners. Another clinical supervisor acted as a simulated patient. [Methods] A Wilcoxon signed-rank test was performed to compare skills between before and after OSCE-based learning, and a Mann-Whitney U test was used to compare them between therapists with 1 to 2 years (novice) and 3 to 5 years (mid-career) of clinical experience. [Results] While no experience-related differences were observed in behavioral aspects, mid-career therapists exhibited markedly higher scores compared with novices in technical aspects, such as skills to guide patients for standing up, transfer, and dressing. [Conclusion] The OSCE may be sufficiently applicable to postgraduate education systems in workplaces. PMID:25276021

How we give personalised audio feedback after summative OSCEs.

PubMed

Harrison, Christopher J; Molyneux, Adrian J; Blackwell, Sara; Wass, Valerie J

2015-04-01

Students often receive little feedback after summative objective structured clinical examinations (OSCEs) to enable them to improve their performance. Electronic audio feedback has shown promise in other educational areas. We investigated the feasibility of electronic audio feedback in OSCEs. An electronic OSCE system was designed, comprising (1) an application for iPads allowing examiners to mark in the key consultation skill domains, provide "tick-box" feedback identifying strengths and difficulties, and record voice feedback; (2) a feedback website giving students the opportunity to view/listen in multiple ways to the feedback. Acceptability of the audio feedback was investigated, using focus groups with students and questionnaires with both examiners and students. 87 (95%) students accessed the examiners' audio comments; 83 (90%) found the comments useful and 63 (68%) reported changing the way they perform a skill as a result of the audio feedback. They valued its highly personalised, relevant nature and found it much more useful than written feedback. Eighty-nine per cent of examiners gave audio feedback to all students on their stations. Although many found the method easy, lack of time was a factor. Electronic audio feedback provides timely, personalised feedback to students after a summative OSCE provided enough time is allocated to the process.

Brief Analysis of Application of Objective Structured Clinical Examination (OSCE) in Graduation Exams of Clinical Medical Students

ERIC Educational Resources Information Center

Du, Yihua; Yu, Ke; Li, Xiaohong; Wang, Feng; Wang, Tingting

2011-01-01

This article gives a brief introduction to the Objective Structured Clinical Examination (OSCE) and analyzes developmental progress of OSCE at both home and abroad and standardized patients' application in OSCE. Also, this article expounds application of OSCE in graduation exam of clinical medical students. Finally, this article summarizes…

Reliability of the OSCE for Physical and Occupational Therapists

PubMed Central

Sakurai, Hiroaki; Kanada, Yoshikiyo; Sugiura, Yoshito; Motoya, Ikuo; Wada, Yosuke; Yamada, Masayuki; Tomita, Masao; Tanabe, Shigeo; Teranishi, Toshio; Tsujimura, Toru; Sawa, Syunji; Okanishi, Tetsuo

2014-01-01

[Purpose] To examine agreement rates between faculty members and clinical supervisors as OSCE examiners. [Subjects] The study subjects were involved physical and occupational therapists working in clinical environments for 1 to 5 years after graduating from training schools as OSCE examinees, and a physical or occupational therapy faculty member and a clinical supervisor as examiners. Another clinical supervisor acted as a simulated patient. [Methods] The agreement rate between the examiners for each OSCE item was calculated based on Cohen’s kappa coefficient to confirm inter-rater reliability. [Results] The agreement rates for the behavioral aspects of the items were higher in the second than in the first examination. Similar increases were also observed in the agreement rates for the technical aspects until the initiation of each activity; however, the rates decreased during the middle to terminal stages of continuous movements. [Conclusion] The results may reflect the recent implementation of measures for the integration of therapist education in training schools and clinical training facilities. PMID:25202170

A Comparative Analysis of the Costs of Administration of an OSCE.

ERIC Educational Resources Information Center

Cusimano, Michael D.; And Others

1994-01-01

A study compared the costs of a six-station structured oral examination and an objective structured clinical examination (OSCE) for a surgery clerkship, assessing both faculty and materials costs. The OSCE was found to be more time consuming and expensive. Cost-cutting measures and guidelines to assist medical schools in selecting test type are…

A procedural skills OSCE: assessing technical and non-technical skills of internal medicine residents.

PubMed

Pugh, Debra; Hamstra, Stanley J; Wood, Timothy J; Humphrey-Murto, Susan; Touchie, Claire; Yudkowsky, Rachel; Bordage, Georges

2015-03-01

Internists are required to perform a number of procedures that require mastery of technical and non-technical skills, however, formal assessment of these skills is often lacking. The purpose of this study was to develop, implement, and gather validity evidence for a procedural skills objective structured clinical examination (PS-OSCE) for internal medicine (IM) residents to assess their technical and non-technical skills when performing procedures. Thirty-five first to third-year IM residents participated in a 5-station PS-OSCE, which combined partial task models, standardized patients, and allied health professionals. Formal blueprinting was performed and content experts were used to develop the cases and rating instruments. Examiners underwent a frame-of-reference training session to prepare them for their rater role. Scores were compared by levels of training, experience, and to evaluation data from a non-procedural OSCE (IM-OSCE). Reliability was calculated using Generalizability analyses. Reliabilities for the technical and non-technical scores were 0.68 and 0.76, respectively. Third-year residents scored significantly higher than first-year residents on the technical (73.5 vs. 62.2%) and non-technical (83.2 vs. 75.1%) components of the PS-OSCE (p < 0.05). Residents who had performed the procedures more frequently scored higher on three of the five stations (p < 0.05). There was a moderate disattenuated correlation (r = 0.77) between the IM-OSCE and the technical component of the PS-OSCE scores. The PS-OSCE is a feasible method for assessing multiple competencies related to performing procedures and this study provides validity evidence to support its use as an in-training examination.

Medical students review of formative OSCE scores, checklists, and videos improves with student-faculty debriefing meetings.

PubMed

Bernard, Aaron W; Ceccolini, Gabbriel; Feinn, Richard; Rockfeld, Jennifer; Rosenberg, Ilene; Thomas, Listy; Cassese, Todd

2017-01-01

Performance feedback is considered essential to clinical skills development. Formative objective structured clinical exams (F-OSCEs) often include immediate feedback by standardized patients. Students can also be provided access to performance metrics including scores, checklists, and video recordings after the F-OSCE to supplement this feedback. How often students choose to review this data and how review impacts future performance has not been documented. We suspect student review of F-OSCE performance data is variable. We hypothesize that students who review this data have better performance on subsequent F-OSCEs compared to those who do not. We also suspect that frequency of data review can be improved with faculty involvement in the form of student-faculty debriefing meetings. Simulation recording software tracks and time stamps student review of performance data. We investigated a cohort of first- and second-year medical students from the 2015-16 academic year. Basic descriptive statistics were used to characterize frequency of data review and a linear mixed-model analysis was used to determine relationships between data review and future F-OSCE performance. Students reviewed scores (64%), checklists (42%), and videos (28%) in decreasing frequency. Frequency of review of all metric and modalities improved when student-faculty debriefing meetings were conducted (p<.001). Among 92 first-year students, checklist review was associated with an improved performance on subsequent F-OSCEs (p = 0.038) by 1.07 percentage points on a scale of 0-100. Among 86 second year students, no review modality was associated with improved performance on subsequent F-OSCEs. Medical students review F-OSCE checklists and video recordings less than 50% of the time when not prompted. Student-faculty debriefing meetings increased student data reviews. First-year student's review of checklists on F-OSCEs was associated with increases in performance on subsequent F-OSCEs, however this

[Clinical competence evaluation using the Objective Structured Clinical Examination (OSCE) in medical internship at UNAM].

PubMed

Trejo Mejía, Juan Andrés; Martínez González, Adrián; Méndez Ramírez, Ignacio; Morales López, Sara; Ruiz Pérez, Leobardo C; Sánchez Mendiola, Melchor

2014-01-01

The Objective Structured Clinical Examination (OSCE) is a widely used measurement tool to assess clinical competence in the health sciences. There is little published evidence of its use in Mexican medical schools. To assess clinical competence in medical students with an OSCE, before and after the Medical Internship. Prospective cohort study, pre- post-test research design. The assessed population was medical students at UNAM Faculty of Medicine in Mexico in their Internship year. The instrument was an 18-stations OSCE, three stations per academic area of the Internship curriculum. We assessed the clinical competence of 278 students in a pretest OSCE when starting the Internship year, and tested them 10 months later with an equivalent post-test OSCE. The sample of students was 30.4% of the total Internship population. Test reliability with Cronbach's alpha was 0.62 in the pre-test and 0.64 in the post-test. The global mean score in the pretest OSCE was 55.6 ± 6.6 and in the post-test 63.2 ± 5.7 (p < 0.001), with a Cohen's d of 1.2. The clinical competence of medical students measured with an OSCE is higher after the medical internship year. This difference suggests that the internship can influence the development of clinical competence in medical students.

Medical students review of formative OSCE scores, checklists, and videos improves with student-faculty debriefing meetings

PubMed Central

Bernard, Aaron W.; Ceccolini, Gabbriel; Feinn, Richard; Rockfeld, Jennifer; Rosenberg, Ilene; Thomas, Listy; Cassese, Todd

2017-01-01

ABSTRACT Background: Performance feedback is considered essential to clinical skills development. Formative objective structured clinical exams (F-OSCEs) often include immediate feedback by standardized patients. Students can also be provided access to performance metrics including scores, checklists, and video recordings after the F-OSCE to supplement this feedback. How often students choose to review this data and how review impacts future performance has not been documented. Objective: We suspect student review of F-OSCE performance data is variable. We hypothesize that students who review this data have better performance on subsequent F-OSCEs compared to those who do not. We also suspect that frequency of data review can be improved with faculty involvement in the form of student-faculty debriefing meetings. Design: Simulation recording software tracks and time stamps student review of performance data. We investigated a cohort of first- and second-year medical students from the 2015-16 academic year. Basic descriptive statistics were used to characterize frequency of data review and a linear mixed-model analysis was used to determine relationships between data review and future F-OSCE performance. Results: Students reviewed scores (64%), checklists (42%), and videos (28%) in decreasing frequency. Frequency of review of all metric and modalities improved when student-faculty debriefing meetings were conducted (p<.001). Among 92 first-year students, checklist review was associated with an improved performance on subsequent F-OSCEs (p = 0.038) by 1.07 percentage points on a scale of 0-100. Among 86 second year students, no review modality was associated with improved performance on subsequent F-OSCEs. Conclusion: Medical students review F-OSCE checklists and video recordings less than 50% of the time when not prompted. Student-faculty debriefing meetings increased student data reviews. First-year student’s review of checklists on F-OSCEs was associated with

Evaluating verbal and non-verbal communication skills, in an ethnogeriatric OSCE.

PubMed

Collins, Lauren G; Schrimmer, Anne; Diamond, James; Burke, Janice

2011-05-01

Communication during medical interviews plays a large role in patient adherence, satisfaction with care, and health outcomes. Both verbal and non-verbal communication (NVC) skills are central to the development of rapport between patients and healthcare professionals. The purpose of this study was to assess the role of non-verbal and verbal communication skills on evaluations by standardized patients during an ethnogeriatric Objective Structured Clinical Examination (OSCE). Interviews from 19 medical students, residents, and fellows in an ethnogeriatric OSCE were analyzed. Each interview was videotaped and evaluated on a 14 item verbal and an 8 item non-verbal communication checklist. The relationship between verbal and non-verbal communication skills on interview evaluations by standardized patients were examined using correlational analyses. Maintaining adequate facial expression (FE), using affirmative gestures (AG), and limiting both unpurposive movements (UM) and hand gestures (HG) had a significant positive effect on perception of interview quality during this OSCE. Non-verbal communication skills played a role in perception of overall interview quality as well as perception of culturally competent communication. Incorporating formative and summative evaluation of both verbal and non-verbal communication skills may be a critical component of curricular innovations in ethnogeriatrics, such as the OSCE. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Quality Control of an OSCE Using Generalizability Theory and Many-Faceted Rasch Measurement

ERIC Educational Resources Information Center

Iramaneerat, Cherdsak; Yudkowsky, Rachel; Myford, Carol M.; Downing, Steven M.

2008-01-01

An Objective Structured Clinical Examination (OSCE) is an effective method for evaluating competencies. However, scores obtained from an OSCE are vulnerable to many potential measurement errors that cases, items, or standardized patients (SPs) can introduce. Monitoring these sources of errors is an important quality control mechanism to ensure…

Evaluation of the OSC-TV iterative reconstruction algorithm for cone-beam optical CT.

PubMed

Matenine, Dmitri; Mascolo-Fortin, Julia; Goussard, Yves; Després, Philippe

2015-11-01

The present work evaluates an iterative reconstruction approach, namely, the ordered subsets convex (OSC) algorithm with regularization via total variation (TV) minimization in the field of cone-beam optical computed tomography (optical CT). One of the uses of optical CT is gel-based 3D dosimetry for radiation therapy, where it is employed to map dose distributions in radiosensitive gels. Model-based iterative reconstruction may improve optical CT image quality and contribute to a wider use of optical CT in clinical gel dosimetry. This algorithm was evaluated using experimental data acquired by a cone-beam optical CT system, as well as complementary numerical simulations. A fast GPU implementation of OSC-TV was used to achieve reconstruction times comparable to those of conventional filtered backprojection. Images obtained via OSC-TV were compared with the corresponding filtered backprojections. Spatial resolution and uniformity phantoms were scanned and respective reconstructions were subject to evaluation of the modulation transfer function, image uniformity, and accuracy. The artifacts due to refraction and total signal loss from opaque objects were also studied. The cone-beam optical CT data reconstructions showed that OSC-TV outperforms filtered backprojection in terms of image quality, thanks to a model-based simulation of the photon attenuation process. It was shown to significantly improve the image spatial resolution and reduce image noise. The accuracy of the estimation of linear attenuation coefficients remained similar to that obtained via filtered backprojection. Certain image artifacts due to opaque objects were reduced. Nevertheless, the common artifact due to the gel container walls could not be eliminated. The use of iterative reconstruction improves cone-beam optical CT image quality in many ways. The comparisons between OSC-TV and filtered backprojection presented in this paper demonstrate that OSC-TV can potentially improve the rendering of

Psychiatric OSCE Performance of Students with and without a Previous Core Psychiatry Clerkship

ERIC Educational Resources Information Center

Goisman, Robert M.; Levin, Robert M.; Krupat, Edward; Pelletier, Stephen R.; Alpert, Jonathan E.

2010-01-01

Objective: The OSCE has been demonstrated to be a reliable and valid method by which to assess students' clinical skills. An OSCE station was used to determine whether or not students who had completed a core psychiatry clerkship demonstrated skills that were superior to those who had not taken the clerkship and which areas discriminated between…

Standard setting for OSCEs: trial of borderline approach.

PubMed

Kilminster, Sue; Roberts, Trudie

2004-01-01

OSCE examinations were held in May and June 2002 for all third and fourth year and some fifth year medical students at the University of Leeds. There has been an arbitrary pass mark of 65% for these examinations. However, we recognise that it is important to adopt a systematic approach towards standard setting in all examinations so held a trial of the borderline approach to standard setting for third and fifth year examinations. This paper reports our findings. The results for the year 3 OSCE demonstrated that the borderline approach to standard setting is feasible and offers a method to ensure that the pass standard is both justifiable and credible. It is efficient, requiring much less time than other methods and has the advantage of using the judgements of expert clinicians about actual practice. In addition it offers a way of empowering clinicians because it uses their expertise.

Integration of an Objective Structured Clinical Examination (OSCE) into the dental preliminary exams.

PubMed

Ratzmann, Anja; Wiesmann, Ulrich; Kordaß, Bernd

2012-01-01

In the pre-clinical phase of the study of dentistry at the University of Greifswald, the course "Early Patient Contact (EPC)" is conducted within the framework of Community Medicine/Dentistry. The course is based on three pillars: the patient visiting program, special problem-oriented seminars, and communication training for doctors. The essential goal consists of providing students with real patient contact right at the beginning of their study of dentistry, thus making the study of dentistry patient-based very early on. Students are trained in taking comprehensive anamneses and recording clinical findings. Within the framework of the dental preliminary exams, the course is evaluated using an OSCE on a standardized patient. Furthermore, the added value of an additional training unit (conducting anamnesis and clinical examination) in preparation for the OSCE was evaluated. The exam results of a group without training (control group) were compared with those of a group with training (intervention group). The intervention group performed significantly better than the control on the following items: the total number of points achieved on the OSCE early patient contact, and in the most important points of the anamnesis and clinical examination. In addition, the intervention group tended to score higher in terms of the item "oral health status". The present study showed a positive effect of an additional training unit on students' performance in the OSCE. Taking the limitations of the study and the results of a literature review into account, we recommend conducting such training as preparation for the OSCE.

Evaluation of the OSC-TV iterative reconstruction algorithm for cone-beam optical CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matenine, Dmitri, E-mail: dmitri.matenine.1@ulaval.ca; Mascolo-Fortin, Julia, E-mail: julia.mascolo-fortin.1@ulaval.ca; Goussard, Yves, E-mail: yves.goussard@polymtl.ca

Purpose: The present work evaluates an iterative reconstruction approach, namely, the ordered subsets convex (OSC) algorithm with regularization via total variation (TV) minimization in the field of cone-beam optical computed tomography (optical CT). One of the uses of optical CT is gel-based 3D dosimetry for radiation therapy, where it is employed to map dose distributions in radiosensitive gels. Model-based iterative reconstruction may improve optical CT image quality and contribute to a wider use of optical CT in clinical gel dosimetry. Methods: This algorithm was evaluated using experimental data acquired by a cone-beam optical CT system, as well as complementary numericalmore » simulations. A fast GPU implementation of OSC-TV was used to achieve reconstruction times comparable to those of conventional filtered backprojection. Images obtained via OSC-TV were compared with the corresponding filtered backprojections. Spatial resolution and uniformity phantoms were scanned and respective reconstructions were subject to evaluation of the modulation transfer function, image uniformity, and accuracy. The artifacts due to refraction and total signal loss from opaque objects were also studied. Results: The cone-beam optical CT data reconstructions showed that OSC-TV outperforms filtered backprojection in terms of image quality, thanks to a model-based simulation of the photon attenuation process. It was shown to significantly improve the image spatial resolution and reduce image noise. The accuracy of the estimation of linear attenuation coefficients remained similar to that obtained via filtered backprojection. Certain image artifacts due to opaque objects were reduced. Nevertheless, the common artifact due to the gel container walls could not be eliminated. Conclusions: The use of iterative reconstruction improves cone-beam optical CT image quality in many ways. The comparisons between OSC-TV and filtered backprojection presented in this paper demonstrate that OSC

The Reliability, Validity, and Usefulness of the Objective Structured Clinical Examination (OSCE) in Dental Education

ERIC Educational Resources Information Center

Graham, Roseanna

2010-01-01

This study evaluated the reliability, validity, and educational usefulness of a comprehensive, multidisciplinary Objective Structured Clinical Examination (OSCE) in dental education. The OSCE was administered to dental students at the Columbia University College of Dental Medicine (CDM) before they entered clinical training. Participants in this…

Interactions of oversulfated chondroitin sulfate (OSCS) from different sources with unfractionated heparin.

PubMed

Gray, Angel; Litinas, Evangelos; Jeske, Walter; Fareed, Jawed; Hoppensteadt, Debra

2012-01-01

In 2008, oversulfated chondroitin sulfate (OSCS) was identified as the main contaminant in recalled heparin. Oversulfated chondroitin sulfate can be prepared from bovine (B), porcine (P), shark (Sh), or skate (S) origin and may produce changes in the antithrombotic, bleeding, and hemodynamic profile of heparins. This study examines the interactions of various OSCSs on heparin in animal models of thrombosis and bleeding, as well as on the anticoagulant and antiprotease effects in in vitro assays. Mixtures of 70% unfractionated heparin (UFH) with 30% OSCS from different sources were tested. In the in vitro activated partial thromboplastin time (aPTT) assay, all contaminant mixtures showed a decrease in clotting times. In addition, a significant increase in bleeding time compared to the control (UFH/saline) was observed. In the thrombosis model, no significant differences were observed. The OSCSs significantly increased anti-Xa activity in ex vivo blood samples. These results indicate that various sources of OSCS affect the hemostatic properties of heparin.

A core competency-based objective structured clinical examination (OSCE) can predict future resident performance.

PubMed

Wallenstein, Joshua; Heron, Sheryl; Santen, Sally; Shayne, Philip; Ander, Douglas

2010-10-01

This study evaluated the ability of an objective structured clinical examination (OSCE) administered in the first month of residency to predict future resident performance in the Accreditation Council for Graduate Medical Education (ACGME) core competencies. Eighteen Postgraduate Year 1 (PGY-1) residents completed a five-station OSCE in the first month of postgraduate training. Performance was graded in each of the ACGME core competencies. At the end of 18 months of training, faculty evaluations of resident performance in the emergency department (ED) were used to calculate a cumulative clinical evaluation score for each core competency. The correlations between OSCE scores and clinical evaluation scores at 18 months were assessed on an overall level and in each core competency. There was a statistically significant correlation between overall OSCE scores and overall clinical evaluation scores (R = 0.48, p < 0.05) and in the individual competencies of patient care (R = 0.49, p < 0.05), medical knowledge (R = 0.59, p < 0.05), and practice-based learning (R = 0.49, p < 0.05). No correlation was noted in the systems-based practice, interpersonal and communication skills, or professionalism competencies. An early-residency OSCE has the ability to predict future postgraduate performance on a global level and in specific core competencies. Used appropriately, such information can be a valuable tool for program directors in monitoring residents' progress and providing more tailored guidance. © 2010 by the Society for Academic Emergency Medicine.

Design and performance of radioisotope space power systems based on OSC multitube AMTEC converter designs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Noravian, H.; Or, C.

1997-12-31

This paper extends the analytical procedure described in another paper in these proceedings to analyze a variety of compact and light-weight OSC-designed radioisotope-heated generators. Those generators employed General Purpose Heat Source (GPHS) modules and a converter containing sixteen AMTEC cells of OSC`s revised five-tube design with enhanced cell wall reflectivity described in a companion paper in these proceedings. OSC found that the performance of the generator is primarily a function of the thermal insulation between the outside of the generator`s 16 cells and the inside of its wall. After examining a variety of insulation options, it was found that themore » generator`s performance is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered (i.e., graded-length) multifoil insulation. The OSC design results in a very compact generator, with eight AMTEC cells on each end of the heat source stack. The choice of the five-tube cells makes it possible to expand the BASE tube diameter without increasing the cell diameter. This is important because the eight cells mate well with the stacked GPHS modules. The OSC generator design includes a compliant heat source support and preload arrangement, to hold the heat source modules together during launch, and to maintain thermal contact conductance at the generator`s interfaces despite creep relaxation of its housing. The BOM and EOM (up to 15 years) performances of the revised generators were analyzed for two and three GPHS modules, both for fresh fuel and for aged fuel left over from a spare RTG (Radioisotope Thermoelectric Generator) fueled in 1982. The resulting power outputs were compared with JPL`s latest EOM power demand goals for the Pluto Express and Europa Orbiter missions, and with the generic goals of DOE`s Advanced Radioisotope Power System (ARPS) study. The OSC AMTEC designs yielded

Assessing the Organizational Social Context (OSC) of Child Welfare Systems: Implications for Research and Practice

ERIC Educational Resources Information Center

Glisson, Charles; Green, Philip; Williams, Nathaniel J.

2012-01-01

Objective: The study: (1) provides the first assessment of the a "priori" measurement model and psychometric properties of the Organizational Social Context (OSC) measurement system in a US nationwide probability sample of child welfare systems; (2) illustrates the use of the OSC in constructing norm-based organizational culture and climate…

The value of best-practice guidelines for OSCEs in a postgraduate program in an Australian remote area setting.

PubMed

Jeffrey, Carol A; Mitchell, Marion L; Henderson, Amanda; Lenthall, Sue; Knight, Sabina; Glover, Pauline; Kelly, Michelle; Nulty, Duncan; Groves, Michele

2014-01-01

Nurses in remote areas of Australia are the primary healthcare professionals, who need to be able to deliver comprehensive and culturally sensitive care to clients, many of whom are Indigenous Australians. Adequate and specific preparation for practice is crucial to the quality of care delivered by remote area nurses (RANs). Objective structured clinical examinations (OSCE) provide an excellent opportunity for student practice in a simulated environment that is safe, authentic, fair and valid when well constructed. Seven integrated best practice guidelines (BPGs), previously developed by project team members to inform OSCEs within educational programs, provided guidance in restructuring the OSCE. This paper provides a detailed analysis of the value of BPGs used in the development, teaching and learning, and evaluation of OSCEs in a rural and remote postgraduate course for RANs. A pre-site visit to the Centre for Remote Health, Alice Springs, Northern Territory, was conducted with modification of the course and previous OSCE according to BPGs. Following delivery of the course and OSCE, evaluations occurred via a mixed method approach. Student surveys (n=15) and focus groups (n=13) and staff interviews (n=5) provided an in-depth analysis of their perceptions of the revised OSCE. Descriptive statistics were used to describe the student sample. The narrative data were transcribed verbatim and analysed using content analysis. Triangulation was achieved with the convergence of the separate data sources focusing on themes and patterns within and between students and tutors. All 15 students and five tutors provided feedback. The majority of student participants had limited experience in working in remote area nursing prior to participation and therefore the opportunities that availed themselves were critical in adequately equipping them with the requisite knowledge, skills and abilities. Three themes emerged from the data: (1) value of common and significant events in OSCE

Use of an objective structured clinical exam (OSCE) for early identification of communication skills deficits in interns.

PubMed

Goldhamer, Mary Ellen J; Cohen, Amy; Brooks, Michelle; Macklin, Eric A; Co, John Patrick T; Weinstein, Debra

2018-01-01

There is limited information about whether OSCE during GME orientation can identify trainee communication deficits before these become evident via clinical performance evaluations. Ninety-seven interns matriculating to eight residency programs in six specialties at four hospitals participated in a nine-station communication skills OSCE. Ratings were based on the "Kalamazoo, adapted" communication skills checklist. Possible association with intern performance evaluations was assessed by repeated-measures logistic regression and ROC curves were generated. The mean OSCE score was 4.08 ± 0.27 with a range of 3.3-4.6. Baseline OSCE scores were associated with subsequent communication concerns recorded by faculty, based on 1591 evaluations. A 0.1-unit decrease in the OSCE communication score was associated with an 18% higher odds of being identified with a communication concern by faculty evaluation (odds ratio 1.18, 95% CI 1.01-1.36, p = 0.034). ROC curves did not demonstrate a "cut-off" score (AUC= 0.558). Non-faculty evaluators were 3-5 times more likely than faculty evaluators to identify communication deficits, based on 1900 evaluations. Lower OSCE performance was associated with faculty communication concerns on performance evaluations; however, a "cut-off" score was not demonstrated that could identify trainees for potential early intervention. Multi-source evaluation also identified trainees with communication skills deficits.

Recommended OSC design and analysis of AMTEC power system for outer-planet missions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Noravian, H.; Or, C.

1999-01-01

The paper describes OSC designs and analyses of AMTEC cells and radioisotope power systems for possible application to NASA{close_quote}s Europa Orbiter and Pluto Kuiper Express missions, and compares their predicted performance with JPL{close_quote}s preliminary mission goals. The latest cell and generator designs presented here were the culmination of studies covering a wide variety of generator configurations and operating parameters. The many steps and rationale leading to OSC{close_quote}s design evolution and materials selection were discussed in earlier publications and will not be repeated here except for a description of OSC{close_quote}s latest design, including a recent heat source support scheme and cellmore » configuration that have not been described in previous publications. As shown, that heat source support scheme eliminates all contact between the heat source and the AMTEC (Alkali Metal Thermal-to-Electrical Conversion) cells, which simplifies the generator{close_quote}s structural design as well as its fabrication and assembly procedure. An additional purpose of the paper is to describe a revised cell design and fabrication procedure which represent a major departure from previous OSC designs. Previous cells had a uniform diameter, but in the revised design the cell wall beyond the BASE tubes has a greatly reduced diameter. The paper presents analytical performance predictions which show that the revised ({open_quotes}chimney{close_quotes}) cell design yields substantially higher efficiencies than the previous (cylindrical) design. This makes it possible to meet and substantially exceed the JPL-stipulated EOM power goal with four instead of six General Purpose Heat Source (GPHS) modules, resulting in a one-third reduction in the heat source mass, cost, and fuel requirements. OSC{close_quote}s performance predictions were based on its techniques for the coupled thermal, electrical, and fluid flow analyses of AMTEC generators. Those analytical

Construct Validity of an Objective Structured Clinical Examination (OSCE) in Psychiatry: Associations with the Clinical Skills Examination and Other Indicators

ERIC Educational Resources Information Center

Park, Robin S.; Chibnall, John T.; Blaskiewicz, Robert J.; Furman, Gail E.; Powell, Jill K.; Mohr, Clinton J.

2004-01-01

Objective: The construct validity of checklist and global process scores for an objective structured clinical examination (OSCE) in psychiatry was assessed. Multiple regression analysis was used to predict psychiatry OSCE scores from the clinical skills examination, an obstetrics/gynecology (OB/GYN) OSCE, and the National Board of Medical…

Assessment of photoselective vaporization of prostate skills during Urology Objective Structured Clinical Examinations (OSCE)

PubMed Central

Noureldin, Yasser A.; Elkoushy, Mohamed A.; Fahmy, Nader; Carrier, Serge; Elhilali, Mostafa M.; Andonian, Sero

2015-01-01

Introduction: We evaluated the use of the GreenLight Simulator (GL-SIM) (American Medical Systems, Guelph, ON) in the skill assessment of postgraduate trainees (PGTs) in photoselective vaporization of the prostate (PVP). We also sought to determine whether previous PVP experience or GL-SIM practice improved performance. Methods: PGTs in postgraduate years (PGY-3 to PGY-5) from all 4 Quebec urology training programs were recruited during 2 annual Objective Structured Clinical Examinations (OSCEs). During a 20-minute OSCE station, PGTs were asked to perform 2 exercises: (1) identification of endoscopic landmarks and (2) a PVP of a 30-g normal prostate. Grams vaporized, global scores, and number of correct anatomical landmarks were recorded and correlated with PGY level, practice on the GL-SIM, and previous PVP experience. Results: In total, 25 PGTs were recruited at each OSCE, with 13 PGTs participating in both OSCEs. When comparing scores from the first and second OSCEs, there was a significant improvement in the number of grams vaporized (2.9 vs. 4.3 g; p = 0.003) and global score (100 vs. 165; p = 0.03). There was good correlation between the number of previously performed PVPs and the global score (r = 0.4, p = 0.04). Similarly, PGTs with previous practice on the GL-SIM had significantly higher global score (100.6 vs. 162.6; p = 0.04) and grams vaporized (3.1 vs. 4.1 g; p = 0.04) when compared with those who did not practice on GL-SIM. Furthermore, there were significantly more competent PGTs among those who had previously practiced on the GL-SIM (32.7% vs. 10.2%; p = 0.009). PGY level did not significantly affect grams vaporized or global score (p > 0.05). Conclusion: Performance on the GL-SIM at OSCEs significantly correlated with previous practice on the GL-SIM and previous PVP experience rather than PGY level. Furthermore, there were significantly more competent PGTs among those who had previously practiced on the GL-SIM. PMID:25737763

Assessing the Organizational Social Context (OSC) of child welfare systems: implications for research and practice.

PubMed

Glisson, Charles; Green, Philip; Williams, Nathaniel J

2012-09-01

The study: (1) provides the first assessment of the a priori measurement model and psychometric properties of the Organizational Social Context (OSC) measurement system in a US nationwide probability sample of child welfare systems; (2) illustrates the use of the OSC in constructing norm-based organizational culture and climate profiles for child welfare systems; and (3) estimates the association of child welfare system-level organizational culture and climate profiles with individual caseworker-level job satisfaction and organizational commitment. The study applies confirmatory factor analysis (CFA) and hierarchical linear models (HLM) analysis to a US nationwide sample of 1,740 caseworkers from 81 child welfare systems participating in the second National Survey of Child and Adolescent Wellbeing (NSCAW II). The participating child welfare systems were selected using a national probability procedure reflecting the number of children served by child welfare systems nationwide. The a priori OSC measurement model is confirmed in this nationwide sample of child welfare systems. In addition, caseworker responses to the OSC scales generate acceptable to high scale reliabilities, moderate to high within-system agreement, and significant between-system differences. Caseworkers in the child welfare systems with the best organizational culture and climate profiles report higher levels of job satisfaction and organizational commitment. Organizational climates characterized by high engagement and functionality, and organizational cultures characterized by low rigidity are associated with the most positive work attitudes. The OSC is the first valid and reliable measure of organizational culture and climate with US national norms for child welfare systems. The OSC provides a useful measure of Organizational Social Context for child welfare service improvement and implementation research efforts which include a focus on child welfare system culture and climate. Copyright © 2012

Introducing the Objective Structured Clinical Examination (OSCE) in the Undergraduate Psychiatric Curriculum: Evaluation after One Year

ERIC Educational Resources Information Center

Zahid, Muhammad Ajmal; Al-Zayed, Adel; Ohaeri, Jude; Varghese, Ramani

2011-01-01

Objective: The Objective Structured Clinical Examination (OSCE) was introduced in undergraduate psychiatry clerkship in 2008. The authors studied the effect of OSCE on the students' performance. Methods: The "short case" (SC) and "oral examination" (OE), two of the five components of the previous assessment format, were…

OSC in the 1970s: a springboard for a career in optical engineering

NASA Astrophysics Data System (ADS)

Harvey, James E.

2014-09-01

Anecdotes and recollections from a graduate student at the Optical Sciences Center (OSC) in the late 1960s and early 1970s. The early faculty of the OCS fostered an exciting environment where even graduate students served significant roles on major government research contracts. Teamwork and collaboration between research groups was often required to meet the contract goals. This unique learning experience at the OSC almost 50 years ago served as a springboard for a satisfying and rewarding career in Optical Engineering.

Use of the OSCE to Evaluate Brief Communication Skills Training for Dental Students

PubMed Central

Cannick, Gabrielle F.; Horowitz, Alice M.; Garr, David R.; Reed, Susan G.; Neville, Brad W.; Day, Terry A.; Woolson, Robert F.; Lackland, Daniel T.

2009-01-01

Although communications competency is recommended by the American Dental Education Association, only a few (n=5) dental schools report evaluating students’ skills using a competency examination for communication. This study used an objective structured clinical examination (OSCE) to evaluate dental students’ competency in interpersonal and tobacco cessation communication skills. All students were evaluated on their interpersonal communication skills at baseline and at six months post-OSCE by standardized patients and on their tobacco cessation communication skills by two independent raters. First- and second-year dental students (n=104) were randomized to a control or intervention group. One month after the baseline OSCE, students in the intervention group participated in a two-hour training session in which faculty members communicated with a standardized patient during a head and neck examination and counseled the patient about tobacco cessation. There were no statistically significant differences from baseline to post-test between the intervention and control group students as measured by the OSCE. However, among first-year students, both the intervention (n=23) and control (n=21) groups significantly increased in tobacco cessation communication scores. Second-year students in both intervention (n=24) and control (n=28) groups declined in interpersonal communication skills from baseline to post-test. Overall, this one-shot intervention was not successful, and results suggest that a comprehensive communication skills training course may be more beneficial than a single, brief training session for improving dental students’ communication skills. PMID:17761627

Standard Setting for OSCEs: Trial of Borderline Approach

ERIC Educational Resources Information Center

Kilminster, Sue; Roberts, Trudie

2004-01-01

OSCE examinations were held in May and June 2002 for all third and fourth year and some fifth year medical students at the University of Leeds. There has been an arbitrary pass mark of 65% for these examinations. However, we recognise that it is important to adopt a systematic approach towards standard setting in all examinations so held a trial…

Assessing Communication Skills of Medical Students in Objective Structured Clinical Examinations (OSCE)--A Systematic Review of Rating Scales.

PubMed

Cömert, Musa; Zill, Jördis Maria; Christalle, Eva; Dirmaier, Jörg; Härter, Martin; Scholl, Isabelle

2016-01-01

Teaching and assessment of communication skills have become essential in medical education. The Objective Structured Clinical Examination (OSCE) has been found as an appropriate means to assess communication skills within medical education. Studies have demonstrated the importance of a valid assessment of medical students' communication skills. Yet, the validity of the performance scores depends fundamentally on the quality of the rating scales used in an OSCE. Thus, this systematic review aimed at providing an overview of existing rating scales, describing their underlying definition of communication skills, determining the methodological quality of psychometric studies and the quality of psychometric properties of the identified rating scales. We conducted a systematic review to identify psychometrically tested rating scales, which have been applied in OSCE settings to assess communication skills of medical students. Our search strategy comprised three databases (EMBASE, PsycINFO, and PubMed), reference tracking and consultation of experts. We included studies that reported psychometric properties of communication skills assessment rating scales used in OSCEs by examiners only. The methodological quality of included studies was assessed using the COnsensus based Standards for the selection of health status Measurement INstruments (COSMIN) checklist. The quality of psychometric properties was evaluated using the quality criteria of Terwee and colleagues. Data of twelve studies reporting on eight rating scales on communication skills assessment in OSCEs were included. Five of eight rating scales were explicitly developed based on a specific definition of communication skills. The methodological quality of studies was mainly poor. The psychometric quality of the eight rating scales was mainly intermediate. Our results reveal that future psychometric evaluation studies focusing on improving the methodological quality are needed in order to yield psychometrically

Development, implementation, and evaluation of an integrated multidisciplinary Objective Structured Clinical Examination (OSCE) in primary health care settings within limited resources.

PubMed

Abdelaziz, Adel; Hany, Mohamed; Atwa, Hani; Talaat, Wagdy; Hosny, Somaya

2016-01-01

In ordinary circumstances, objective structured clinical examination (OSCE) is a resource-intensive assessment method. In case of developing and implementing multidisciplinary OSCE, there is no doubt that the cost will be greater. Through this study a research project was conducted to develop, implement and evaluate a multidisciplinary OSCE model within limited resources. This research project went through the steps of blueprinting, station writing, resources reallocation, implementation and finally evaluation. The developed model was implemented in the Primary Health Care (PHC) program which is one of the pillars of the Community-Based undergraduate curriculum of the Faculty of Medicine, Suez Canal University (FOM-SCU). Data for evaluation of the implemented OSCE model were derived from two resources. First, feedback of the students and assessors through self-administered questionnaires was obtained. Second, evaluation of the OSCE psychometrics was done. The deliverables of this research project included a set of validated integrated multi-disciplinary and low cost OSCE stations with an estimated reliability index of 0.6. After having this experience, we have a critical mass of faculty members trained on blueprinting and station writing and a group of trained assessors, facilitators and role players. Also there is a state of awareness among students on how to proceed in this type of OSCE which renders future implementation more feasible.

M-OSCE as a method to measure dental hygiene students' critical thinking: a pilot study.

PubMed

McComas, Martha J; Wright, Rebecca A; Mann, Nancy K; Cooper, Mary D; Jacks, Mary E

2013-04-01

Educators in all academic disciplines have been encouraged to utilize assessment strategies to evaluate students' critical thinking. The purpose of this study was to assess the viability of the modified objective structured clinical examination (m-OSCE) to evaluate critical thinking in dental hygiene education. This evaluation utilized a convenience sample of senior dental hygiene students. Students participated in the m-OSCE in which portions of a patient case were revealed at four stations. The exam consisted of multiple-choice questions intended to measure students' ability to utilize critical thinking skills. Additionally, there was one fill-in-the-blank question and a treatment plan that was completed at the fifth station. The results of this study revealed that the m-OSCE did not reliably measure dental hygiene students' critical thinking. Statistical analysis found no satisfactory reliability within the multiple-choice questions and moderately reliable results within the treatment planning portion of the examination. In addition, the item analysis found gaps in students' abilities to transfer clinical evidence/data to basic biomedical knowledge as demonstrated through the multiple-choice questioning results. This outcome warrants further investigation of the utility of the m-OSCE, with a focus on modifications to the evaluation questions, grading rubric, and patient case.

A fast 4D cone beam CT reconstruction method based on the OSC-TV algorithm.

PubMed

Mascolo-Fortin, Julia; Matenine, Dmitri; Archambault, Louis; Després, Philippe

2018-01-01

Four-dimensional cone beam computed tomography allows for temporally resolved imaging with useful applications in radiotherapy, but raises particular challenges in terms of image quality and computation time. The purpose of this work is to develop a fast and accurate 4D algorithm by adapting a GPU-accelerated ordered subsets convex algorithm (OSC), combined with the total variation minimization regularization technique (TV). Different initialization schemes were studied to adapt the OSC-TV algorithm to 4D reconstruction: each respiratory phase was initialized either with a 3D reconstruction or a blank image. Reconstruction algorithms were tested on a dynamic numerical phantom and on a clinical dataset. 4D iterations were implemented for a cluster of 8 GPUs. All developed methods allowed for an adequate visualization of the respiratory movement and compared favorably to the McKinnon-Bates and adaptive steepest descent projection onto convex sets algorithms, while the 4D reconstructions initialized from a prior 3D reconstruction led to better overall image quality. The most suitable adaptation of OSC-TV to 4D CBCT was found to be a combination of a prior FDK reconstruction and a 4D OSC-TV reconstruction with a reconstruction time of 4.5 minutes. This relatively short reconstruction time could facilitate a clinical use.

Peer-assisted teaching student tutors as examiners in an orthopedic surgery OSCE station – pros and cons

PubMed Central

Melcher, Peter; Zajonz, Dirk; Roth, Andreas; Heyde, Christoph-E.; Ghanem, Mohamed

2016-01-01

Background: The OSCE (objective structured clinical examination) is composed of oral and practical examination in order to examine students’ abilities to imply clinical examination techniques and to interact with patients. The examiners for this procedure can be either lecturers or peers. The aim of this work is to evaluate the peer-assisted teaching student tutors as examiners in an orthopedic surgery OSCE station. Methods: We analyzed the OSCE data from 2013 to 2015. During this period over 300 medical students were examined each year. An evaluation was conducted at an orthopedic station and examined by peer students to assess the advantages and disadvantages of peer-assisted teaching student tutors as examiners. Results: We have noticed that student peers are more flexible regarding their schedule and they have been well trained for OSCE. Concerning the economic aspects, student peers are clearly of major economic advantage. Disadvantages were not reported in our study probably because peers were well trained and the checklists are monitored regularly. Conclusion: Student peers in OSCE are of major advantage due to their flexible time schedule and relatively low costs. They must be well trained and the checklists are to be monitored regularly. Our study shows that peer tutor examiners conducted the examination as competent as lecture examiners. However, legal restrictions on the employment of students should be considered. PMID:27500078

How well do second-year students learn physical diagnosis? Observational study of an Objective Structured Clinical Examination (OSCE).

PubMed

Hamann, Claus; Volkan, Kevin; Fishman, Mary B; Silvestri, Ronald C; Simon, Steven R; Fletcher, Suzanne W

2002-01-01

Little is known about using the Objective Structured Clinical Examination (OSCE) in physical diagnosis courses. The purpose of this study was to describe student performance on an OSCE in a physical diagnosis course. Cross-sectional study at Harvard Medical School, 1997-1999, for 489 second-year students. Average total OSCE score was 57% (range 39-75%). Among clinical skills, students scored highest on patient interaction (72%), followed by examination technique (65%), abnormality identification (62%), history-taking (60%), patient presentation (60%), physical examination knowledge (47%), and differential diagnosis (40%) (p <.0001). Among 16 OSCE stations, scores ranged from 70% for arthritis to 29% for calf pain (p <.0001). Teaching sites accounted for larger adjusted differences in station scores, up to 28%, than in skill scores (9%) (p <.0001). Students scored higher on interpersonal and technical skills than on interpretive or integrative skills. Station scores identified specific content that needs improved teaching.

A collaborative comparison of objective structured clinical examination (OSCE) standard setting methods at Australian medical schools.

PubMed

Malau-Aduli, Bunmi Sherifat; Teague, Peta-Ann; D'Souza, Karen; Heal, Clare; Turner, Richard; Garne, David L; van der Vleuten, Cees

2017-12-01

A key issue underpinning the usefulness of the OSCE assessment to medical education is standard setting, but the majority of standard-setting methods remain challenging for performance assessment because they produce varying passing marks. Several studies have compared standard-setting methods; however, most of these studies are limited by their experimental scope, or use data on examinee performance at a single OSCE station or from a single medical school. This collaborative study between 10 Australian medical schools investigated the effect of standard-setting methods on OSCE cut scores and failure rates. This research used 5256 examinee scores from seven shared OSCE stations to calculate cut scores and failure rates using two different compromise standard-setting methods, namely the Borderline Regression and Cohen's methods. The results of this study indicate that Cohen's method yields similar outcomes to the Borderline Regression method, particularly for large examinee cohort sizes. However, with lower examinee numbers on a station, the Borderline Regression method resulted in higher cut scores and larger difference margins in the failure rates. Cohen's method yields similar outcomes as the Borderline Regression method and its application for benchmarking purposes and in resource-limited settings is justifiable, particularly with large examinee numbers.

How well do second-year students learn physical diagnosis? Observational study of an objective structured clinical examination (OSCE)

PubMed Central

Hamann, Claus; Volkan, Kevin; Fishman, Mary B; Silvestri, Ronald C; Simon, Steven R; Fletcher, Suzanne W

2002-01-01

Background Little is known about using the Objective Structured Clinical Examination (OSCE) in physical diagnosis courses. The purpose of this study was to describe student performance on an OSCE in a physical diagnosis course. Methods Cross-sectional study at Harvard Medical School, 1997–1999, for 489 second-year students. Results Average total OSCE score was 57% (range 39–75%). Among clinical skills, students scored highest on patient interaction (72%), followed by examination technique (65%), abnormality identification (62%), history-taking (60%), patient presentation (60%), physical examination knowledge (47%), and differential diagnosis (40%) (p < .0001). Among 16 OSCE stations, scores ranged from 70% for arthritis to 29% for calf pain (p < .0001). Teaching sites accounted for larger adjusted differences in station scores, up to 28%, than in skill scores (9%) (p < .0001). Conclusions Students scored higher on interpersonal and technical skills than on interpretive or integrative skills. Station scores identified specific content that needs improved teaching. PMID:11888484

Assessing Communication Skills of Medical Students in Objective Structured Clinical Examinations (OSCE) - A Systematic Review of Rating Scales

PubMed Central

Cömert, Musa; Zill, Jördis Maria; Christalle, Eva; Dirmaier, Jörg; Härter, Martin; Scholl, Isabelle

2016-01-01

Background Teaching and assessment of communication skills have become essential in medical education. The Objective Structured Clinical Examination (OSCE) has been found as an appropriate means to assess communication skills within medical education. Studies have demonstrated the importance of a valid assessment of medical students’ communication skills. Yet, the validity of the performance scores depends fundamentally on the quality of the rating scales used in an OSCE. Thus, this systematic review aimed at providing an overview of existing rating scales, describing their underlying definition of communication skills, determining the methodological quality of psychometric studies and the quality of psychometric properties of the identified rating scales. Methods We conducted a systematic review to identify psychometrically tested rating scales, which have been applied in OSCE settings to assess communication skills of medical students. Our search strategy comprised three databases (EMBASE, PsycINFO, and PubMed), reference tracking and consultation of experts. We included studies that reported psychometric properties of communication skills assessment rating scales used in OSCEs by examiners only. The methodological quality of included studies was assessed using the COnsensus based Standards for the selection of health status Measurement INstruments (COSMIN) checklist. The quality of psychometric properties was evaluated using the quality criteria of Terwee and colleagues. Results Data of twelve studies reporting on eight rating scales on communication skills assessment in OSCEs were included. Five of eight rating scales were explicitly developed based on a specific definition of communication skills. The methodological quality of studies was mainly poor. The psychometric quality of the eight rating scales was mainly intermediate. Discussion Our results reveal that future psychometric evaluation studies focusing on improving the methodological quality are needed

The first OSCE; does students' experience of performing in public affect their results?

PubMed

Chan, Michael; Bax, Nigel; Woodley, Caroline; Jennings, Michael; Nicolson, Rod; Chan, Philip

2015-03-26

Personal qualities have been shown to affect students' exam results. We studied the effect of experience, and level, of public performance in music, drama, dance, sport, and debate at the time of admission to medical school as a predictor of student achievement in their first objective structured clinical examination (OSCE). A single medical school cohort (n = 265) sitting their first clinical exam in 2011 as third year students were studied. Pre-admission statements made at the time of application were coded for their stated achievements in the level of public performance; participation in each activity was scored 0-3, where 0 was no record, 1 = leisure time activity, 2 = activity at school or local level, 3 = activity at district, regional or national level. These scores were correlated to OSCE results by linear regression and t-test. Comparison was made between the highest scoring students in each area, and students scoring zero by t-test. There was a bell shaped distribution in public performance score in this cohort. There was no significant linear regression relationship between OSCE results and overall performance score, or between any subgroups. There was a significant difference between students with high scores in theatre, debate and vocal music areas, grouped together as verbal performance, and students scoring zero in these areas. (p < 0.05, t-test) with an effect size of 0.4. We found modest effects from pre-admission experience of verbal performance on students' scores in the OSCE examination. As these data are taken from students' admission statements, we call into question the received wisdom that such statements are unreliable.

Validity evidence for an OSCE to assess competency in systems-based practice and practice-based learning and improvement: a preliminary investigation.

PubMed

Varkey, Prathibha; Natt, Neena; Lesnick, Timothy; Downing, Steven; Yudkowsky, Rachel

2008-08-01

To determine the psychometric properties and validity of an OSCE to assess the competencies of Practice-Based Learning and Improvement (PBLI) and Systems-Based Practice (SBP) in graduate medical education. An eight-station OSCE was piloted at the end of a three-week Quality Improvement elective for nine preventive medicine and endocrinology fellows at Mayo Clinic. The stations assessed performance in quality measurement, root cause analysis, evidence-based medicine, insurance systems, team collaboration, prescription errors, Nolan's model, and negotiation. Fellows' performance in each of the stations was assessed by three faculty experts using checklists and a five-point global competency scale. A modified Angoff procedure was used to set standards. Evidence for the OSCE's validity, feasibility, and acceptability was gathered. Evidence for content and response process validity was judged as excellent by institutional content experts. Interrater reliability of scores ranged from 0.85 to 1 for most stations. Interstation correlation coefficients ranged from -0.62 to 0.99, reflecting case specificity. Implementation cost was approximately $255 per fellow. All faculty members agreed that the OSCE was realistic and capable of providing accurate assessments. The OSCE provides an opportunity to systematically sample the different subdomains of Quality Improvement. Furthermore, the OSCE provides an opportunity for the demonstration of skills rather than the testing of knowledge alone, thus making it a potentially powerful assessment tool for SBP and PBLI. The study OSCE was well suited to assess SBP and PBLI. The evidence gathered through this study lays the foundation for future validation work.

Effect of Clinically Discriminating, Evidence-Based Checklist Items on the Reliability of Scores from an Internal Medicine Residency OSCE

ERIC Educational Resources Information Center

Daniels, Vijay J.; Bordage, Georges; Gierl, Mark J.; Yudkowsky, Rachel

2014-01-01

Objective structured clinical examinations (OSCEs) are used worldwide for summative examinations but often lack acceptable reliability. Research has shown that reliability of scores increases if OSCE checklists for medical students include only clinically relevant items. Also, checklists are often missing evidence-based items that high-achieving…

Qualitative differences between traditional and rural-longitudinal medical student OSCE performance.

PubMed

Zink, Therese; Power, David V; Olson, Kenneth; Harris, Ilene B; Brooks, Kathleen D

2010-01-01

To ensure adequate observation, supervision, and mentoring of trainees, long-term preceptorships or apprenticeships are being reestablished in medical education. Equivalence in academic performance has been demonstrated between longitudinal students in the Rural Physician Associate Program (RPAP), who spend 9 months in a rural community during their third year of medical school, and their peers who complete their clerkships at different hospitals and clinics (traditional). We qualitatively reviewed the end of session Objective Structured Clinical Examination (OSCE) for both groups and compared their performances. The high and low performers on four OSCE scenarios (cough, dysuria in a teen, preventive care in an older male, medication reconciliation) for two cohorts of students: longitudinal (n=47) and traditional primary care clerkship students (n=60) were selected for review. These 16 videotapes were reviewed independently by three researchers. The themes and subthemes were discussed over four meetings. Both high and low scoring longitudinal students demonstrated more consistent use of rapport building skills. Longitudinal students appeared to have an effective pattern in their patient interactions and were more rehearsed at explaining preventive care recommendations such as the pros and cons of the prostate-specific antigen (PSA) test. Traditional students displayed a more complete mastery of the adolescent interview and followed a mnemonic taught during lecture. Qualitative assessment of OSCE data reveals information not captured in the quantitative scores. In this study, longitudinal students demonstrated better mastery of rapport building and content knowledge and had an effective routine to their patient encounters not evident in the traditional students' scenarios.

Effect of clinically discriminating, evidence-based checklist items on the reliability of scores from an Internal Medicine residency OSCE.

PubMed

Daniels, Vijay J; Bordage, Georges; Gierl, Mark J; Yudkowsky, Rachel

2014-10-01

Objective structured clinical examinations (OSCEs) are used worldwide for summative examinations but often lack acceptable reliability. Research has shown that reliability of scores increases if OSCE checklists for medical students include only clinically relevant items. Also, checklists are often missing evidence-based items that high-achieving learners are more likely to use. The purpose of this study was to determine if limiting checklist items to clinically discriminating items and/or adding missing evidence-based items improved score reliability in an Internal Medicine residency OSCE. Six internists reviewed the traditional checklists of four OSCE stations classifying items as clinically discriminating or non-discriminating. Two independent reviewers augmented checklists with missing evidence-based items. We used generalizability theory to calculate overall reliability of faculty observer checklist scores from 45 first and second-year residents and predict how many 10-item stations would be required to reach a Phi coefficient of 0.8. Removing clinically non-discriminating items from the traditional checklist did not affect the number of stations (15) required to reach a Phi of 0.8 with 10 items. Focusing the checklist on only evidence-based clinically discriminating items increased test score reliability, needing 11 stations instead of 15 to reach 0.8; adding missing evidence-based clinically discriminating items to the traditional checklist modestly improved reliability (needing 14 instead of 15 stations). Checklists composed of evidence-based clinically discriminating items improved the reliability of checklist scores and reduced the number of stations needed for acceptable reliability. Educators should give preference to evidence-based items over non-evidence-based items when developing OSCE checklists.

77 FR 28638 - OSC Forms And Survey Renewal for FY 2012-Request for Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-15

... employees; and (2) the interpretation and enforcement of Hatch Act provisions on political activity in... Possible Prohibited Political Activity (Violation of the Hatch Act)); (4) Office of Special Counsel (OSC...

77 FR 22614 - OSC Forms and Survey Renewal for FY 2012-Request for Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-16

... employees; and (2) the interpretation and enforcement of Hatch Act provisions on political activity in... Possible Prohibited Political Activity (Violation of the Hatch Act)); (4) Office of Special Counsel (OSC...

Geriatric Medicine Fellows' Experiences and Attitudes toward an Objective Structured Clinical Examination (OSCE)

ERIC Educational Resources Information Center

Bagri, Anita S.; Zaw, Khin M.; Milanez, Marcos N.; Palacios, Juan J.; Qadri, Syeda S.; Bliss, Linda A.; Roos, Bernard A.; Ruiz, Jorge G.

2009-01-01

A total of 8 geriatric medicine fellows participated in an objective structured clinical examination (OSCE) assessing communication skills and clinical reasoning in common geriatric syndromes. To determine their perceptions about the experience, we conducted surveys and semistructured interviews. We analyzed the survey data using descriptive…

Standardised clients as assessors in a veterinary communication OSCE: a reliability and validity study.

PubMed

Artemiou, E; Adams, C L; Hecker, K G; Vallevand, A; Violato, C; Coe, J B

2014-11-22

In human medicine, standardised patients (SP) have been shown to reliably and accurately assess learners' communication performance in high-stakes certification Objective Structured Clinical Examinations (OSCE), offering a feasible way to reduce the need for recruitment, time commitment and coordination of faculty assessors. In this study, we evaluated the use of standardised clients (SC) as a viable option for assessing veterinary students' communication performance. We designed a four-station, two-track communication skills OSCE. SC assessors used an adapted nine-item Liverpool Undergraduate Communication Assessment Scale (LUCAS). Faculty used a 21-item checklist derived from the Calgary-Cambridge Guide (CCG) and a five-point global rating scale. Participants were second year veterinary students (n=96). For the four stations, intrastation reliability (α) ranged from 0.63 to 0.82 for the LUCAS, and 0.73 to 0.87 for the CCG. The interstation reliability coefficients were 0.85 for the LUCAS and 0.89 for the CGG. The calculated Generalisability (G) coefficients were 0.62 for the LUCAS and 0.60 for the CGG. Supporting construct validity, SC and faculty assessors showed a significant correlation between the LUCAS and CCG total percent scores (r=0.45, P<0.001), and likewise between the LUCAS and global rating scores (r=0.49, P<0.001).Study results support that SC assessors offer a reliable and valid approach for assessing veterinary communication OSCE. British Veterinary Association.

Assessing nursing clinical skills competence through objective structured clinical examination (OSCE) for open distance learning students in Open University Malaysia.

PubMed

Oranye, Nelson Ositadimma; Ahmad, Che'an; Ahmad, Nora; Bakar, Rosnida Abu

2012-06-01

The objective structured clinical skills examination (OSCE) has over the years emerged as a method of evaluating clinical skills in most medical and allied professions. Although its validity and objectivity has evoked so much debate in the literature, little has been written about its application in non-traditional education systems such as in distance learning. This study examined clinical skills competence among practising nursing students who were enrolled in a distance learning programme. The study examined the effect of work and years of nursing practice on nurses' clinical skills competence. This study used observational design whereby nursing students' clinical skills were observed and scored in five OSCE stations. Two instruments were used for the data collection - A self-administered questionnaire on the students' bio-demographic data, and a check list on the clinical skills which the examiners rated on a four point scale. The findings revealed that 14% of the nurses had level four competence, which indicated that they could perform the tasks correctly and complete. However, 12% failed the OSCE, even though they had more than 10 years experience in nursing and post basic qualifications. Inter-rater reliability was 0.92 for the five examiners. Factor analysis indicated that five participant factors accounted for 74.1% of the variations in clinical skills performance. An OSCE is a necessary assessment tool that should be continuously applied in nursing education, regardless of the mode of the education program, the student's years of experience or his/her clinical placement. This study validates the need for OSCE in both the design of tertiary nursing degree programs and the assessment of nurses' clinical competency level.

Training Family Medicine Residents in Effective Communication Skills While Utilizing Promotoras as Standardized Patients in OSCEs: A Health Literacy Curriculum.

PubMed

Pagels, Patti; Kindratt, Tiffany; Arnold, Danielle; Brandt, Jeffrey; Woodfin, Grant; Gimpel, Nora

2015-01-01

Introduction. Future health care providers need to be trained in the knowledge and skills to effectively communicate with their patients with limited health literacy. The purpose of this study is to develop and evaluate a curriculum designed to increase residents' health literacy knowledge, improve communication skills, and work with an interpreter. Materials and Methods. Family Medicine residents (N = 25) participated in a health literacy training which included didactic lectures and an objective structured clinical examination (OSCE). Community promotoras acted as standardized patients and evaluated the residents' ability to measure their patients' health literacy, communicate effectively using the teach-back and Ask Me 3 methods, and appropriately use an interpreter. Pre- and postknowledge, attitudes, and postdidactic feedback were obtained. We compared OSCE scores from the group that received training (didactic group) and previous graduates. Residents reported the skills they used in practice three months later. Results. Family Medicine residents showed an increase in health literacy knowledge (p = 0.001) and scored in the adequately to expertly performed range in the OSCE. Residents reported using the teach-back method (77.8%) and a translator more effectively (77.8%) three months later. Conclusions. Our innovative health literacy OSCE can be replicated for medical learners at all levels of training.

Training Family Medicine Residents in Effective Communication Skills While Utilizing Promotoras as Standardized Patients in OSCEs: A Health Literacy Curriculum

PubMed Central

Pagels, Patti; Kindratt, Tiffany; Arnold, Danielle; Brandt, Jeffrey; Woodfin, Grant; Gimpel, Nora

2015-01-01

Introduction. Future health care providers need to be trained in the knowledge and skills to effectively communicate with their patients with limited health literacy. The purpose of this study is to develop and evaluate a curriculum designed to increase residents' health literacy knowledge, improve communication skills, and work with an interpreter. Materials and Methods. Family Medicine residents (N = 25) participated in a health literacy training which included didactic lectures and an objective structured clinical examination (OSCE). Community promotoras acted as standardized patients and evaluated the residents' ability to measure their patients' health literacy, communicate effectively using the teach-back and Ask Me 3 methods, and appropriately use an interpreter. Pre- and postknowledge, attitudes, and postdidactic feedback were obtained. We compared OSCE scores from the group that received training (didactic group) and previous graduates. Residents reported the skills they used in practice three months later. Results. Family Medicine residents showed an increase in health literacy knowledge (p = 0.001) and scored in the adequately to expertly performed range in the OSCE. Residents reported using the teach-back method (77.8%) and a translator more effectively (77.8%) three months later. Conclusions. Our innovative health literacy OSCE can be replicated for medical learners at all levels of training. PMID:26491565

Summative assessment of undergraduates' communication competence in challenging doctor-patient encounters. Evaluation of the Düsseldorf CoMeD-OSCE.

PubMed

Mortsiefer, Achim; Immecke, Janine; Rotthoff, Thomas; Karger, André; Schmelzer, Regine; Raski, Bianca; Schmitten, Jürgen In der; Altiner, Attila; Pentzek, Michael

2014-06-01

To evaluate the summative assessment (OSCE) of a communication training programme for dealing with challenging doctor-patient encounters in the 4th study year. Our OSCE consists of 4 stations (breaking bad news, guilt and shame, aggressive patients, shared decision making), using a 4-item global rating (GR) instrument. We calculated reliability coefficients for different levels, discriminability of single items and interrater reliability. Validity was estimated by gender differences and accordance between GR and a checklist. In a pooled sample of 456 students in 3 OSCEs over 3 terms, total reliability was α=0.64, reliability coefficients for single stations were >0.80, and discriminability in 3 of 4 stations was within the range of 0.4-0.7. Except for one station, interrater reliability was moderate to strong. Reliability on item level was poor and pointed to some problems with the use of the GR. The application of the GR on regular undergraduate medical education shows moderate reliability in need of improvement and some traits of validity. Ongoing development and evaluation is needed with particular regard to the training of the examiners. Our CoMeD-OSCE proved suitable for the summative assessment of communication skills in challenging doctor-patient encounters. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

How to assess communication, professionalism, collaboration and the other intrinsic CanMEDS roles in orthopedic residents: use of an objective structured clinical examination (OSCE)

PubMed Central

Dwyer, Tim; Takahashi, Susan Glover; Hynes, Melissa Kennedy; Herold, Jodi; Wasserstein, David; Nousiainen, Markku; Ferguson, Peter; Wadey, Veronica; Murnaghan, M. Lucas; Leroux, Tim; Semple, John; Hodges, Brian; Ogilvie-Harris, Darrell

2014-01-01

Background Assessing residents’ understanding and application of the 6 intrinsic CanMEDS roles (communicator, professional, manager, collaborator, health advocate, scholar) is challenging for postgraduate medical educators. We hypothesized that an objective structured clinical examination (OSCE) designed to assess multiple intrinsic CanMEDS roles would be sufficiently reliable and valid. Methods The OSCE comprised 6 10-minute stations, each testing 2 intrinsic roles using case-based scenarios (with or without the use of standardized patients). Residents were evaluated using 5-point scales and an overall performance rating at each station. Concurrent validity was sought by correlation with in-training evaluation reports (ITERs) from the last 12 months and an ordinal ranking created by program directors (PDs). Results Twenty-five residents from postgraduate years (PGY) 0, 3 and 5 participated. The interstation reliability for total test scores (percent) was 0.87, while reliability for each of the communicator, collaborator, manager and professional roles was greater than 0.8. Total test scores, individual station scores and individual CanMEDS role scores all showed a significant effect by PGY level. Analysis of the PD rankings of intrinsic roles demonstrated a high correlation with the OSCE role scores. A correlation was seen between ITER and OSCE for the communicator role, while the ITER medical expert and total scores highly correlated with the communicator, manager and professional OSCE scores. Conclusion An OSCE designed to assess the intrinsic CanMEDS roles was sufficiently valid and reliable for regular use in an orthopedic residency program. PMID:25078926

A Comparison of Standard-Setting Procedures for an OSCE in Undergraduate Medical Education.

ERIC Educational Resources Information Center

Kaufman, David M.; Mann, Karen V.; Muijtjens, Arno M. M.; van der Vleuten, Cees P. M.

2000-01-01

Compared four standard-setting procedures for an objective structure clinical examination (OSCE) in medical education. Applied Angoff, borderline, relative, and holistic procedures to the data used to establish a cutoff score for a pass/fail decision. The Angoff and borderline procedures gave similar results; however, the relative and holistic…

40 CFR 300.145 - Special teams and other assistance available to OSCs/RPMs.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 28 2014-07-01 2014-07-01 false Special teams and other assistance... SUBSTANCES POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.145 Special teams and other assistance available to OSCs/RPMs. (a) The NSF is a special team established by the USCG...

40 CFR 300.145 - Special teams and other assistance available to OSCs/RPMs.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 28 2011-07-01 2011-07-01 false Special teams and other assistance... SUBSTANCES POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.145 Special teams and other assistance available to OSCs/RPMs. (a) The NSF is a special team established by the USCG...

40 CFR 300.145 - Special teams and other assistance available to OSCs/RPMs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Special teams and other assistance... SUBSTANCES POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.145 Special teams and other assistance available to OSCs/RPMs. (a) The NSF is a special team established by the USCG...

40 CFR 300.145 - Special teams and other assistance available to OSCs/RPMs.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 29 2013-07-01 2013-07-01 false Special teams and other assistance... SUBSTANCES POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.145 Special teams and other assistance available to OSCs/RPMs. (a) The NSF is a special team established by the USCG...

40 CFR 300.145 - Special teams and other assistance available to OSCs/RPMs.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 29 2012-07-01 2012-07-01 false Special teams and other assistance... SUBSTANCES POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.145 Special teams and other assistance available to OSCs/RPMs. (a) The NSF is a special team established by the USCG...

Competency-Based Training: Objective Structured Clinical Exercises (OSCE) in Marriage and Family Therapy

ERIC Educational Resources Information Center

Miller, John K.

2010-01-01

The field of marriage and family therapy (MFT) has recently engaged in the process of defining core competencies for the profession. Many MFT training programs are adapting their curriculum to develop more competency-based training strategies. The Objective Structured Clinical "Examination" (OSCE) is widely used in the medical profession to assess…

Using a teaching OSCE to prompt learners to engage with patients who talk about religion and/or spirituality.

PubMed

Ledford, Christy J W; Seehusen, Dean A; Canzona, Mollie Rose; Cafferty, Lauren A

2014-01-01

The objective structured clinical examination (OSCE) has only occasionally been used as a teaching tool. The authors describe the initial use of an educational innovation consisting of a teaching OSCE used as "sensitizing practice," followed by personal, guided, and group reflection. Staff and resident physicians and one medical student (N = 28) at a community hospital's family medicine residency participated in the innovation during August 2012. The initial use of the educational innovation allowed learners to engage in a potentially challenging conversation with a standardized patient about religion and/or spirituality (R/S). The aim of the innovation was not to equip learners with a particular tactic to introduce or discuss R/S but, rather, to prompt learners to engage in mindful practice with patients who identify R/S as part of their biopsychosocial contexts. Written, dyadic, and group reflection added value to the OSCE by allowing participants to reflect on a difficult learning objective over time. Participants moved along the stages-of-change continuum when engaging in guided reflection compared with personal reflection. Additionally, all participants provided evidence of at least the preparation stage at the time of guided reflection. By following the OSCE's sensitizing practice with three periods of reflection, learners were enabled first, to recognize the need for readiness to address challenging communication topics (in this case, R/S) and, second, to reflect on practiced strategies for those conversations. The educational innovation can help learners become more aware of and skillful in dealing with difficult physician-patient communication topics.

The dialysis orders objective structured clinical examination (OSCE): a formative assessment for nephrology fellows.

PubMed

Prince, Lisa K; Campbell, Ruth C; Gao, Sam W; Kendrick, Jessica; Lebrun, Christopher J; Little, Dustin J; Mahoney, David L; Maursetter, Laura A; Nee, Robert; Saddler, Mark; Watson, Maura A; Yuan, Christina M

2018-04-01

Few quantitative nephrology-specific simulations assess fellow competency. We describe the development and initial validation of a formative objective structured clinical examination (OSCE) assessing fellow competence in ordering acute dialysis. The three test scenarios were acute continuous renal replacement therapy, chronic dialysis initiation in moderate uremia and acute dialysis in end-stage renal disease-associated hyperkalemia. The test committee included five academic nephrologists and four clinically practicing nephrologists outside of academia. There were 49 test items (58 points). A passing score was 46/58 points. No item had median relevance less than 'important'. The content validity index was 0.91. Ninety-five percent of positive-point items were easy-medium difficulty. Preliminary validation was by 10 board-certified volunteers, not test committee members, a median of 3.5 years from graduation. The mean score was 49 [95% confidence interval (CI) 46-51], κ = 0.68 (95% CI 0.59-0.77), Cronbach's α = 0.84. We subsequently administered the test to 25 fellows. The mean score was 44 (95% CI 43-45); 36% passed the test. Fellows scored significantly less than validators (P < 0.001). Of evidence-based questions, 72% were answered correctly by validators and 54% by fellows (P = 0.018). Fellows and validators scored least well on the acute hyperkalemia question. In self-assessing proficiency, 71% of fellows surveyed agreed or strongly agreed that the OSCE was useful. The OSCE may be used to formatively assess fellow proficiency in three common areas of acute dialysis practice. Further validation studies are in progress.

True communication skills assessment in interdepartmental OSCE stations: Standard setting using the MAAS-Global and EduG.

PubMed

Setyonugroho, Winny; Kropmans, Thomas; Murphy, Ruth; Hayes, Peter; van Dalen, Jan; Kennedy, Kieran M

2018-01-01

Comparing outcome of clinical skills assessment is challenging. This study proposes reliable and valid comparison of communication skills (1) assessment as practiced in Objective Structured Clinical Examinations (2). The aim of the present study is to compare CS assessment, as standardized according to the MAAS Global, between stations in a single undergraduate medical year. An OSCE delivered in an Irish undergraduate curriculum was studied. We chose the MAAS-Global as an internationally recognized and validated instrument to calibrate the OSCE station items. The MAAS-Global proportion is the percentage of station checklist items that can be considered as 'true' CS. The reliability of the OSCE was calculated with G-Theory analysis and nested ANOVA was used to compare mean scores of all years. MAAS-Global scores in psychiatry stations were significantly higher than those in other disciplines (p<0.03) and above the initial pass mark of 50%. The higher students' scores in psychiatry stations were related to higher MAAS-Global proportions when compared to the general practice stations. Comparison of outcome measurements, using the MAAS Global as a standardization instrument, between interdisciplinary station checklists was valid and reliable. The MAAS-Global was used as a single validated instrument and is suggested as gold standard. Copyright © 2017. Published by Elsevier B.V.

The dialysis orders objective structured clinical examination (OSCE): a formative assessment for nephrology fellows

PubMed Central

Prince, Lisa K; Campbell, Ruth C; Gao, Sam W; Kendrick, Jessica; Lebrun, Christopher J; Little, Dustin J; Mahoney, David L; Maursetter, Laura A; Nee, Robert; Saddler, Mark; Watson, Maura A

2018-01-01

Abstract Background Few quantitative nephrology-specific simulations assess fellow competency. We describe the development and initial validation of a formative objective structured clinical examination (OSCE) assessing fellow competence in ordering acute dialysis. Methods The three test scenarios were acute continuous renal replacement therapy, chronic dialysis initiation in moderate uremia and acute dialysis in end-stage renal disease-associated hyperkalemia. The test committee included five academic nephrologists and four clinically practicing nephrologists outside of academia. There were 49 test items (58 points). A passing score was 46/58 points. No item had median relevance less than ‘important’. The content validity index was 0.91. Ninety-five percent of positive-point items were easy–medium difficulty. Preliminary validation was by 10 board-certified volunteers, not test committee members, a median of 3.5 years from graduation. The mean score was 49 [95% confidence interval (CI) 46–51], κ = 0.68 (95% CI 0.59–0.77), Cronbach’s α = 0.84. Results We subsequently administered the test to 25 fellows. The mean score was 44 (95% CI 43–45); 36% passed the test. Fellows scored significantly less than validators (P < 0.001). Of evidence-based questions, 72% were answered correctly by validators and 54% by fellows (P = 0.018). Fellows and validators scored least well on the acute hyperkalemia question. In self-assessing proficiency, 71% of fellows surveyed agreed or strongly agreed that the OSCE was useful. Conclusions The OSCE may be used to formatively assess fellow proficiency in three common areas of acute dialysis practice. Further validation studies are in progress. PMID:29644053

Influence of Marital Status on Attitude of Midwives towards OSCE and Their Performance in the Examination in Akwa Ibom and Cross River States, Nigeria

ERIC Educational Resources Information Center

Duke, Emon Umoe; Mgbekem, Mary Achi; Nsemo, Alberta David; Ojong-Alacia, Mary Manyo; Nkwonta, Chigozie A.; Mobolaji-Olajide, O. M.

2015-01-01

This quantitative study investigated the influence of marital status on the midwives' attitude towards OSCE and how this affects their performance in the examination. Two hypotheses guided the study. HO 1 sort to find out if there exist a significant influence of marital status of midwives on their attitude towards OSCE as well as performance in…

Long-term prospective teaching effectivity of practical skills training and a first OSCE in cranio maxillofacial surgery for dental students.

PubMed

Landes, Constantin A; Hoefer, Sebastian; Schuebel, Florian; Ballon, Alexander; Teiler, Anna; Tran, Andreas; Weber, Roxane; Walcher, Felix; Sader, Robert

2014-07-01

Basic skills in oral/CMF surgery should be taught effectively to dental students as surgical skills training is traditionally under-represented in the dental curriculum compared to its later need in daily clinical practice. Rigid curricular time frames and prospectively condensed professional education foster new effective teaching and examination formats. Transmitting and assessing clinical competence objectively (independent of subjective bias), reliably (repeatable, inter-rater consistency) and valid (representative, structured task selection) was intended and evaluated in oral/CMF surgery skills acquisition starting in summer 2009. A small-group practical skills training (PST) day initiated a one-week practical training course, covering previously formulated learning objectives. An objective structured clinical evaluation (OSCE) was held at the end of each semester. Theoretical background knowledge and clinical skills should have to be memorized within a representative number of practical tasks (test stations). A first semester (26 students) used classical practical training alone as controls, the following semesters (171 students) had PST, considered as a study group. All 197 students were assessed with OSCE's over a 3-year period. An instructor held PST based on presentations, videos and practical training, including mannequins, with pairs of students. This included history taking, communication and interpretation of laboratory/image diagnostics, structured clinical facial examination, fracture diagnosis, venipuncture, suturing, biopsy and wire loops on pig jaws for manual and clinical skills, which were later incorporated in OSCE stations. OSCE average results increased from 63.3 ± 9.7% before and to 75.5 ± 10% after the inclusion of PST (p < 0.05). Knowledge diffusion between sittings on the same test date and between consecutive semesters was insignificant. Students and faculty rated their learning/teaching experience "very good" to "good". PST was

A Procedural Skills OSCE: Assessing Technical and Non-Technical Skills of Internal Medicine Residents

ERIC Educational Resources Information Center

Pugh, Debra; Hamstra, Stanley J.; Wood, Timothy J.; Humphrey-Murto, Susan; Touchie, Claire; Yudkowsky, Rachel; Bordage, Georges

2015-01-01

Internists are required to perform a number of procedures that require mastery of technical and non-technical skills, however, formal assessment of these skills is often lacking. The purpose of this study was to develop, implement, and gather validity evidence for a procedural skills objective structured clinical examination (PS-OSCE) for internal…

Enhanced Web-Based Otitis Study Case vs Simple Paper-Case: Impact on Medical Student Objective Structured Clinical Exam (OSCE) Performance.

PubMed

Malloy, Michael H

2002-12-01

Distance education methods have taken on greater importance as medical student education has moved off campus into the community. What the best methods are for conveying information to students at distant sites has not been determined. To determine if students at distant community sites who received an otitis media study case by e-mail that was enhanced with a referral to a web-based otitis study case, performed better on otitis OSCE stations than students who received the same case not enhanced with visuals or referrals to a web-based otitis case. Students were randomized by community site to receive either the enhanced (E) or simple otitis study case (S). Students were e-mailed an otitis media study case during the 5th week of the rotation. Those randomized to the E-case received a case that started with a case scenario followed by a "Task" that instructed them to go to this web address: http://www.aap.org/otitismedia/www/vc/ear/index.cfm (American Academy of Pediatrics Otitis Web Site). They were then to select "Case 1" which was a continuation of the case scenario present on their e-mail. A list of learning objectives was also printed on the e-mail. Students receiving the S-case viewed the same case scenario and objectives, but were not instructed to go to the web-page. All students rotated through two OSCE otitis stations. In the first station they interviewed a simulated patient(OSCE-SP) and counseled her on the management of her 12 month old with otitis. Within that station they viewed a video of a pneumoscopic exam of two ears, one ear with otitis and the other ear normal. At the 2 nd otitis station the student presented the case to a faculty and was asked a series of questions about otitis media(OSCE-PR). Scores on the two stations were compared by group. There were 198 students who took the OSCE. 178 (90%) responded to a survey that indicated they had opened and read the e-mailed case. There were 87 students in the E-group and 91 in the S-group. The mean

Assessment of percutaneous renal access skills during Urology Objective Structured Clinical Examinations (OSCE)

PubMed Central

Noureldin, Yasser A.; Elkoushy, Mohamed A.; Andonian, Sero

2015-01-01

Introduction: The first objective was to assess percutaneous renal access (PCA) skills of urology postgraduate trainees (PGTs) during the Objective Structured Clinical Examinations (OSCEs). The second objective was to determine whether previous experience with percutaneous nephrolithotomy (PCNL) improved performance. Methods: After obtaining ethics approval, we recruited PGTs from two urology programs in Quebec between postgraduate years (PGY-3 to PGY-5). Each trainee was asked to answer a short questionnaire regarding previous experience in endourologic procedures. After a 3-minute orientation on the PERC Mentor simulator (Simbionix, Cleveland, OH), each trainee was asked to perform task 4, where they had to correctly access all of the renal calyces and pop the balloons in a normal left kidney model. We collected and analyzed data from the questionnaire and the performance report generated by the simulator. Results: In total, 13 PGTs participated in this study. PGTs had performed a median of 200 (range: 50–1000) cystoscopies, 50 (range: 10–125) TURBTs, 30 (range: 0–100) TURPs, 5 (range: 0–50) laser prostatectomies, and 50 (range: 2–125) ureteroscopies prior to this OSCE. PGTs with previous PCNL experience (8/13) had performed a mean of 18.6 ± 6.3 PCNLs. PGTs with previous PCNL experience performed significantly better in terms of shorter fluoroscopy time (10 ± 1.5 vs. 5.1 ± 0.7 min; p = 0.04), fewer attempts required for successful puncture of the pelvi-calyceal system (PCS) (21 ± 2.3 vs. 13 ± 1.8; p = 0.02), and had significantly lower complications in terms of fewer infundibular injury (7.4 ± 1.5 vs. 2 ± 0.4; p = 0.004) and fewer PCS perforations (11 ± 1.7 vs. 4.5 ± 1.2; p = 0.01). Conclusion: It is feasible to use the PERC Mentor simulator during OSCEs to assess PCA skills of urology PGTs. PGTs who had previous PCNL experience performed significantly better with fewer complications. PMID:25844094

Undesired variance due to examiner stringency/leniency effect in communication skill scores assessed in OSCEs.

PubMed

Harasym, Peter H; Woloschuk, Wayne; Cunning, Leslie

2008-12-01

Physician-patient communication is a clinical skill that can be learned and has a positive impact on patient satisfaction and health outcomes. A concerted effort at all medical schools is now directed at teaching and evaluating this core skill. Student communication skills are often assessed by an Objective Structure Clinical Examination (OSCE). However, it is unknown what sources of error variance are introduced into examinee communication scores by various OSCE components. This study primarily examined the effect different examiners had on the evaluation of students' communication skills assessed at the end of a family medicine clerkship rotation. The communication performance of clinical clerks from Classes 2005 and 2006 were assessed using six OSCE stations. Performance was rated at each station using the 28-item Calgary-Cambridge guide. Item Response Theory analysis using a Multifaceted Rasch model was used to partition the various sources of error variance and generate a "true" communication score where the effects of examiner, case, and items are removed. Variance and reliability of scores were as follows: communication scores (.20 and .87), examiner stringency/leniency (.86 and .91), case (.03 and .96), and item (.86 and .99), respectively. All facet scores were reliable (.87-.99). Examiner variance (.86) was more than four times the examinee variance (.20). About 11% of the clerks' outcome status shifted using "true" rather than observed/raw scores. There was large variability in examinee scores due to variation in examiner stringency/leniency behaviors that may impact pass-fail decisions. Exploring the benefits of examiner training and employing "true" scores generated using Item Response Theory analyses prior to making pass/fail decisions are recommended.

Undesired Variance Due to Examiner Stringency/Leniency Effect in Communication Skill Scores Assessed in OSCEs

ERIC Educational Resources Information Center

Harasym, Peter H.; Woloschuk, Wayne; Cunning, Leslie

2008-01-01

Physician-patient communication is a clinical skill that can be learned and has a positive impact on patient satisfaction and health outcomes. A concerted effort at all medical schools is now directed at teaching and evaluating this core skill. Student communication skills are often assessed by an Objective Structure Clinical Examination (OSCE).…

Testing clinical competencies in undergraduate nursing education using Objective Structured Clinical Examination (OSCE) – a literature review of international practice

PubMed

Beyer, Angelika; Dreier, Adina; Kirschner, Stefanie; Hoffmann, Wolfgang

2016-07-01

Background: In response to demographic trends in Germany nursing competencies are currently reevaluated. Since these have to be taught and trained in nursing education programs, efficient verification of the success is necessary. OSCEs are internationally well-recognized as a comprehensive tool for that. Aim: In this analysis we identified competencies worldwide, which are tested by OSCEs in undergraduate nursing education programs. Method: An international literature research was conducted. The selection criterion for an article was the specification of at least one verifiable competency. Afterwards the competencies were categorized into knowledge, skills and attitudes according to the German “Fachqualifikationsrahmen Pflege für die hochschulische Bildung”. Results: A total of 36 publications fulfilled all inclusion criteria. Relevant studies were predominantly initiated in the UK, Canada and Australia. Within all categories a total of n = 166 different competencies are mentioned. OSCEs are developed and performed in a broad range of methods. Most frequently skills were verified. The most common topic was sure handling of medication. Other important themes were communicative competencies in relation to patients and the ability of self-evaluation. Discussion/Conclusions: A variation in examination methods is appropriate as different competencies are acquired in preparation of the test. Evaluation took place on an individual or institutional level. Further research is needed.

Exploration of Nursing Faculty Members' Lived Experiences of Objective Structured Clinical Examination (OSCE) in Undergraduate Nursing Education

ERIC Educational Resources Information Center

Obizoba, Cordelia O.

2014-01-01

The purpose of this phenomenological study was to gain an understanding of nursing faculty members' lived experiences of Objective Structured Clinical Examination (OSCE) in undergraduate nursing education. As owners of their programs' curriculum, nursing faculties are charged with the responsibility of providing needed knowledge, skills, and…

Using modified information delivery to enhance the traditional pharmacy OSCE program at TMU - a pilot study.

PubMed

Lin, Che-Wei; Chang, Elizabeth H; Clinciu, Daniel L; Peng, Yun-Ting; Huang, Wen-Chen; Wu, Chien-Chih; Wu, Jen-Chieh; Li, Yu-Chuan

2018-05-01

Objective Structured Clinical Examination (OSCE) has been used in many areas of healthcare training over the years. However, it constantly needs to be upgraded and enhanced due to technological and teaching changes. We aim at implementing an integrative OSCE method which employs informatics via the virtual patient within the pharmacy education curriculum at Taipei Medical University to enhance the pharmacy students' competence for using and disseminating information and to also improve critical thinking and clinical reasoning. We propose an integrated pharmacy OSCE which uses standardized patients and virtual patients (DxR Clinician). To evaluate this method, we designed four simulated stations and pilot tested with 19 students in the first year of the Master in Clinical Pharmacy program. Three stations were simulated as the inpatient pharmacy: 1) History and lab data collection; 2) Prescription review; 3) Calling physician to discuss potential prescription problems. The fourth was simulated as the patient ward station to provide patient education. A satisfaction questionnaire was administered at the end of the study. Students rated their ability of 2.84, 2.37, 2.37, and 3.63 of 5 for each of the four stations, with the second and third being the most difficult stations. The method obtained an average rating of 4.32 of 5 for relevance, 4.16 for improving clinical ability, 4.32 for practicality in future healthcare work, and 4.28 for willing to have another similar learning experience. The integration of Virtual Patient in this study reveals that this assessment method is efficient and practical in many aspects. Most importantly, it provides the test taker with a much closer real-life clinical encounter. Although it is in many ways more difficult, it also provides for better "learning from mistakes" opportunities for test-takers. Copyright © 2017. Published by Elsevier B.V.

Patterns of nucleotide diversity and phenotypes of two domestication related genes (OsC1 and Wx) in indigenous rice varieties in Northeast India

PubMed Central

2014-01-01

Background During the domestication of crops, individual plants with traits desirable for human needs have been selected from their wild progenitors. Consequently, genetic and nucleotide diversity of genes associated with these selected traits in crop plants are expected to be lower than their wild progenitors. In the present study, we surveyed the pattern of nucleotide diversity of two selected trait specific genes, Wx and OsC1, which regulate amylose content and apiculus coloration respectively in cultivated rice varieties. The analyzed samples were collected from a wide geographic area in Northeast (NE) India, and included contrasting phenotypes considered to be associated with selected genes, namely glutinous and nonglutinous grains and colored and colorless apiculus. Results No statistically significant selection signatures were detected in both Wx and OsC1gene sequences. However, low level of selection that varied across the length of each gene was evident. The glutinous type varieties showed higher levels of nucleotide diversity at the Wx locus (πtot = 0.0053) than nonglutinous type varieties (πtot = 0.0043). The OsC1 gene revealed low levels of selection among the colorless apiculus varieties with lower nucleotide diversity (πtot = 0.0010) than in the colored apiculus varieties (πtot = 0.0023). Conclusions The results revealed that functional mutations at Wx and OsC1genes considered to be associated with specific phenotypes do not necessarily correspond to the phenotypes in indigenous rice varieties in NE India. This suggests that other than previously reported genomic regions may also be involved in determination of these phenotypes. PMID:24935343

'Hello, my name is Gabriel, I am the house officer, may I examine you?' or the Objective Santa Christmas Examination (OSCE).

PubMed

Wood, D; Roberts, T; Bradley, P; Lloyd, D; O'Neill, P

1999-12-01

To design a clinical examination of high content validity suitable for use as a formative assessment tool with pre-registration house officers (PRHO'S) towards the end of their first house officer post. A multicentre collaboration between four UK medical schools who offer undergraduate curricula which are problem-based, systems-based, patient-orientated, student-centred, jargon-laden and utterly staff-bewildering. An objective structured clinical examination (OSCE) which is suitable for use with graduates of UK medical schools. It assesses the knowledge, skills and attitudes essential for future careers in a hierarchical system where protecting the senior staff from all forms of irritation is paramount. PRHO'S who excel in this examination get better references. The OSCE format can be used to provide 'real-life' scenarios appropriate to the season.

Improved OSC Amtec generator design to meet goals of JPL's candidate Europa Orbiter mission

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Noravian, H.; Or, C.

1998-07-01

The preceding paper (Paper IECEC.98.244) described OSC's initial designs of AMTEC (Alkali Metal Thermal-to-Electrical Conversion) power systems, consisting of one or two generators, each with 2, 3, or 4 General Purpose Heat Source (GPHS) modules and with 16 refractory AMTEC cells containing 5 Beta Alumina Solid Electrolyte (BASE) tubes; and presented the effect of heat input and voltage output on the generator's BOM evaporator and clad temperatures and on its EOM system efficiency and power output. Comparison of the computed results with JPL's goals for the Europa Orbiter mission showed that all of the initial 16-cell design options yielded eithermore » excessive evaporator and clad temperatures or insufficient EOM power to satisfy the JPL-specified mission goals. The present paper describes modified OSC generator designs with different numbers of AMTEC cells, cell diameters, cell lengths, cell materials, BASE tube lengths, and number of tubes per cell. These efforts succeeded in identifying generator designs with only half the number of AMTEC cells which -- for the same assumptions -- can produce EOM power outputs substantially in excess of JPL's goals for NASA's Europa Orbiter mission while operating well below the prescribed BOM limits on evaporator and clad temperature; and revealed that lowering the emissivity of the generator's housing to raise the cells' condenser temperatures can achieve substantial additional performance improvement. Finally, the paper culminates in programmatic recommendations.« less

Evaluation of a multi-methods approach to the collection and dissemination of feedback on OSCE performance in dental education.

PubMed

Wardman, M J; Yorke, V C; Hallam, J L

2018-05-01

Feedback is an essential part of the learning process, and students expect their feedback to be personalised, meaningful and timely. Objective Structured Clinical Examination (OSCE) assessments allow examiners to observe students carefully over the course of a number of varied station types, across a number of clinical knowledge and skill domains. They therefore present an ideal opportunity to record detailed feedback which allows students to reflect on and improve their performance. This article outlines two methods by which OSCE feedback was collected and then disseminated to undergraduate dental students across 2-year groups in a UK dental school: (i) Individual written feedback comments made by examiners during the examination, (ii) General audio feedback recorded by groups of examiners immediately following the examination. Evaluation of the feedback was sought from students and staff examiners. A multi-methods approach utilising Likert questionnaire items (quantitative) and open-ended feedback questions (qualitative) was used. Data analysis explored student and staff perceptions of the audio and written feedback. A total of 131 students (response rate 68%) and 52 staff examiners (response rate 83%) completed questionnaires. Quantitative data analysis showed that the written and audio formats were reported as a meaningful source of feedback for learning by both students (93% written, 89% audio) and staff (96% written, 92% audio). Qualitative data revealed the complementary nature of both types of feedback. Written feedback gives specific, individual information whilst audio shares general observations and allows students to learn from others. The advantages, limitations and challenges of the feedback methods are discussed, leading to the development of an informed set of implementation guidelines. Written and audio feedback methods are valued by students and staff. It is proposed that these may be very easily applied to OSCEs running in other dental schools. �

Standard Setting in a Small Scale OSCE: A Comparison of the Modified Borderline-Group Method and the Borderline Regression Method

ERIC Educational Resources Information Center

Wood, Timothy J.; Humphrey-Murto, Susan M.; Norman, Geoffrey R.

2006-01-01

When setting standards, administrators of small-scale OSCEs often face several challenges, including a lack of resources, a lack of available expertise in statistics, and difficulty in recruiting judges. The Modified Borderline-Group Method is a standard setting procedure that compensates for these challenges by using physician examiners and is…

Performance of OSC's initial Amtec generator design, and comparison with JPL's Europa Orbiter goals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Noravian, H.; Or, C.

1998-07-01

The procedure for the analysis (with overpotential correction) of multitube AMTEC (Alkali Metal Thermal-to-Electrical Conversion) cells described in Paper IECEC 98-243 was applied to a wide range of multicell radioisotope space power systems. System design options consisting of one or two generators, each with 2, 3, or 4 stacked GPHS (General Purpose Heat Source) modules, identical to those used on previous NASA missions, were analyzed and performance-mapped. The initial generators analyzed by OSC had 8 AMTEC cells on each end of the heat source stack, with five beta-alumina solid electrolyte (BASE) tubes per cell. The heat source and converters inmore » the Orbital generator designs are embedded in a thermal insulation system consisting of Min-K fibrous insulation surrounded by graded-length molybdenum multifoils. Detailed analyses in previous Orbital studies found that such an insulation system could reduce extraneous heat losses to about 10%. For the above design options, the present paper presents the system mass and performance (i.e., the EOM system efficiency and power output and the BOM evaporator and clad temperatures) for a wide range of heat inputs and load voltages, and compares the results with JPL's preliminary goals for the Europa Orbiter mission to be launched in November 2003. The analytical results showed that the initial 16-cell generator designs resulted in either excessive evaporator and clad temperatures and/or insufficient power outputs to meet the JPL-specified mission goals. The computed performance of modified OSC generators with different numbers of AMTEC cells, cell diameters, cell lengths, cell materials, BASE tube lengths, and number of tubes per cell are described in Paper IECEC.98.245 in these proceedings.« less

The influence of first impressions on subsequent ratings within an OSCE station.

PubMed

Wood, Timothy J; Chan, James; Humphrey-Murto, Susan; Pugh, Debra; Touchie, Claire

2017-10-01

Competency-based assessment is placing increasing emphasis on the direct observation of learners. For this process to produce valid results, it is important that raters provide quality judgments that are accurate. Unfortunately, the quality of these judgments is variable and the roles of factors that influence the accuracy of those judgments are not clearly understood. One such factor is first impressions: that is, judgments about people we do not know, made quickly and based on very little information. This study explores the influence of first impressions in an OSCE. Specifically, the purpose is to begin to examine the accuracy of a first impression and its influence on subsequent ratings. We created six videotapes of history-taking performance. Each video was scripted from a real performance by six examinee residents within a single OSCE station. Each performance was re-enacted with six different actors playing the role of the examinees and one actor playing the role of the patient and videotaped. A total of 23 raters (i.e., physician examiners) reviewed each video and were asked to make a global judgment of the examinee's clinical abilities after 60 s (First Impression GR) by providing a rating on a six-point global rating scale and then to rate their confidence in the accuracy of that judgment by providing a rating on a five-point rating scale (Confidence GR). After making these ratings, raters then watched the remainder of the examinee's performance and made another global rating of performance (Final GR) before moving on to the next video. First impression ratings of ability varied across examinees and were moderately correlated to expert ratings (r = .59, 95% CI [-.13, .90]). There were significant differences in mean ratings for three examinees. Correlations ranged from .05 to .56 but were only significant for three examinees. Rater confidence in their first impression was not related to the likelihood of a rater changing their rating between the first

An exploration of student nurses' thoughts and experiences of using a video-recording to assess their performance of cardiopulmonary resuscitation (CPR) during a mock objective structured clinical examination (OSCE).

PubMed

Paul, Fiona

2010-09-01

Cardiopulmonary resuscitation (CPR) is an essential skill taught within undergraduate nursing programmes. At the author's institution, students must pass the CPR objective structured clinical examination (OSCE) before progressing to second year. However, some students have difficulties developing competence in CPR and evidence suggests that resuscitation skills may only be retained for several months. This has implications for practice as nurses are required to be competent in CPR. Therefore, further opportunities for students to develop these skills are necessary. An action research project was conducted with six students who were assessed by an examiner at a video-recorded mock OSCE. Students self-assessed their skills using the video and a checklist. Semi-structured interviews were conducted to compare checklist scores, and explore students' thoughts and experiences of the OSCE. The findings indicate that students may need to repeat this exercise by comparing their previous and current performances to develop both their self-assessment and CPR skills. Although there were some differences between the examiner's and student's checklist scores, all students reported the benefits of participating in this project, e.g. discussion and identification of knowledge and skills deficits, thus emphasising the benefits of formative assessments to prepare students for summative assessments and ultimately clinical practice. (c) 2010 Elsevier Ltd. All rights reserved.

Do primary health centres and hospitals contribute equally towards achievement of the transversal clinical competencies of medical students? Performance on the Objective Structured Clinical Examination (OSCE) in competency acquisition.

PubMed

Soler-González, Jorge; Buti, Miquel; Boada, Jordi; Ayala, Victoria; Peñascal, Eduard; Rodriguez, Toni

2016-01-01

The adaptation of the educational programmes of European faculties of medicine to the European Higher Education Area guidelines has focused curricula design on competence acquisition. Competencies are defined as the achievements of a predetermined level of efficacy in real-world scenarios. Our objective was to assess whether performance on a common competence evaluation test, the Objective Structured Clinical Examination (OSCE), resulted in different scores for second-year students after a practical medical training course took place in a primary health centre (PHC) or in a hospital. A descriptive study was conducted during the 2010-2014 academic year of the OSCE test scores obtained by all second-year students. Faculty of Medicine at the University of Lleida (Catalonia, Spain). We performed a correlation analysis between students who completed their practical medical training at the PHC and hospitals utilising Student's t-test for comparison of means. 423 students who completed internships at the PHC and at hospitals obtained OSCE mean scores of 7.32 (SD; IC) (0.82; 7.18-7.47) points and 7.17 (0.83; 6.07-7.26) points, respectively (p=0.07). Second-year medical students acquired similar competency levels in the two analysed training scenarios. The two areas both serve their teaching purpose. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Team OSCE: A Teaching Modality for Promotion of Multidisciplinary Work in Mental Health Settings.

PubMed

Sharma, Manoj Kumar; Chandra, Prabha S; Chaturvedi, Santosh K

2015-01-01

The objective structured clinical examination has been in use both as an assessment and a teaching modality within the mental health profession. It focuses on individual skill enhancement, the inter-professional understanding of role obligation is helpful in promoting competence as a team as well as role of other team members. The Team OSCE (TOSCE) is an effective way in promoting inter-professional learning. The present work assesses the trainee experience with TOSCE and its utility in clinical care. Twenty-two mental health trainees (17 male and 5 female from psychiatry, clinical psychology and psychiatric social work) got exposure to weekly OSCAF training as well as 2-3 Team OSCAFS on various aspects of clinical work as a part of their clinical training for 3 months. Rating from the trainees were taken on TOSCE feedback checklist. TOSCE was helpful in promoting the understanding role of other team members; shared decision-making, problem-solving, handling unexpected events, giving feedback and closure. The TOSCE may be introduced as a way to work on clinical performance, shared decision-making and inter-professional understanding.

The effect on reliability and sensitivity to level of training of combining analytic and holistic rating scales for assessing communication skills in an internal medicine resident OSCE.

PubMed

Daniels, Vijay John; Harley, Dwight

2017-07-01

Although previous research has compared checklists to rating scales for assessing communication, the purpose of this study was to compare the effect on reliability and sensitivity to level of training of an analytic, a holistic, and a combined analytic-holistic rating scale in assessing communication skills. The University of Alberta Internal Medicine Residency runs OSCEs for postgraduate year (PGY) 1 and 2 residents and another for PGY-4 residents. Communication stations were scored with an analytic scale (empathy, non-verbal skills, verbal skills, and coherence subscales) and a holistic scale. Authors analyzed reliability of individual and combined scales using generalizability theory and evaluated each scale's sensitivity to level of training. For analytic, holistic, and combined scales, 12, 12, and 11 stations respectively yielded a Phi of 0.8 for the PGY-1,2 cohort, and 16, 16, and 14 stations yielded a Phi of 0.8 for the PGY-4 cohort. PGY-4 residents scored higher on the combined scale, the analytic rating scale, and the non-verbal and coherence subscales. A combined analytic-holistic rating scale increased score reliability and was sensitive to level of training. Given increased validity evidence, OSCE developers should consider combining analytic and holistic scales when assessing communication skills. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and analysis of O-S-C triple band wavelength division demultiplexer using cascaded MMI couplers

NASA Astrophysics Data System (ADS)

Chack, Devendra; Kumar, V.; Raghuwanshi, Sanjeev Kumar; Singh, Dev Prakash

2017-01-01

Compact triple O-S-C band wavelength demultiplexer, which consists of series cascaded multimode interference (MMI) couplers has been carried out in this paper. The MMI coupler has been used to drop the wavelengths of 1510 nm and 1550 nm at bar port while the wavelength 1300 nm into the cross port. Then another MMI coupler has been designed to separate the wavelength 1510 nminto one port and wavelength 1550 nm into another port. The triple wavelength demultiplexer function has been performed by choosing a suitable refractive index of the guiding region and geometrical parameters such as the width and length of MMI coupler. Numerical simulation with finite difference beam propagation method (BPM) has been utilized to design and optimize the operation of the proposed triple wavelength demultiplexer. The simulation results show that insertion losses of wavelength O, S and C, bands are 1.884 dB, 1.452 dB and 2.568 dB, respectively, with isolations for each output waveguide ranging from 10 dB to 28.72 dB. The 3-dB bandwidth of insertion loss for 1300 nm, 1510 nm and 1550 nm are 80 nm, 20 nm and 10 nm, respectively.

Communication skills of medical students during the OSCE: Gender-specific differences in a longitudinal trend study.

PubMed

Graf, Joachim; Smolka, Robert; Simoes, Elisabeth; Zipfel, Stephan; Junne, Florian; Holderried, Friederike; Wosnik, Annette; Doherty, Anne M; Menzel, Karina; Herrmann-Werner, Anne

2017-05-02

Communication skills are essential in a patient-centred health service and therefore in medical teaching. Although significant differences in communication behaviour of male and female students are known, gender differences in the performance of students are still under-reported. The aim of this study was to analyse gender differences in communication skills of medical students in the context of an OSCE exam (OSCE = Objective Structured Clinical Examination). In a longitudinal trend study based on seven semester-cohorts, it was analysed if there are gender differences in medical students' communication skills. The students (self-perception) and standardized patients (SP) (external perception) were asked to rate the communication skills using uniform questionnaires. Statistical analysis was performed by using frequency analyses and t-tests in SPSS 21. Across all ratings in the self- and the external perception, there was a significant gender difference in favour of female students performing better in the dimensions of empathy, structure, verbal expression and non-verbal expression. The results of male students deteriorated across all dimensions in the external perception between 2011 and 2014. It is important to consider if gender-specific teaching should be developed, considering the reported differences between female and male students.

The use of a virtual patient case in an OSCE-based exam--a pilot study.

PubMed

Courteille, O; Bergin, R; Stockeld, D; Ponzer, S; Fors, U

2008-01-01

This study focuses on a skills test based clinical assessment where 118 fourth-year medical students at the four teaching hospitals of Karolinska Institutet participated in the same 12-module OSCE. The goal of one of the twelve examination modules was to assess the students' skills and ability to solve a virtual patient (VP) case (the ISP system), which included medical history taking, lab tests, physical examinations and suggestion of a preliminary diagnosis. The primary aim of this study was to evaluate the potential of a VP as a possible tool for assessment of clinical reasoning and problem solving ability among medical students. The feeling of realism of the VP and its possible affective impact on the student's confidence were also investigated. We observed and analysed students' reactions, engagement and performance (activity log files) during their interactive sessions with the simulation. An individual human assistant was provided along with the computer simulation and the videotaped interaction student/assistant was then analysed in detail and related to the students' outcomes. The results indicate possible advantages of using ISP-like systems for assessment. The VP was for instance able to reliably differentiate between students' performances but some weaknesses were also identified, like a confounding influence on students' outcomes by the assistants used. Significant differences, affecting the results, were found between the students in their degree of affective response towards the system as well as the perceived usefulness of assistance. Students need to be trained beforehand in mastering the assessment tool. Rating compliance needs to be targeted before VP-based systems like ISP can be used in exams and if such systems would be used in high-stake exams, the use of human assistants should be limited and scoring rubrics validated (and preferably automated).

[Implementation of bedside training and advanced objective structured clinical examination (OSCE) trial to learn and confirm about pharmacy clinical skills].

PubMed

Tokunaga, Jin; Takamura, Norito; Ogata, Kenji; Setoguchi, Nao; Sato, Keizo

2013-01-01

Bedside training for fourth-year students, as well as seminars in hospital pharmacy (vital sign seminars) for fifth-year students at the Department of Pharmacy of Kyushu University of Health and Welfare have been implemented using patient training models and various patient simulators. The introduction of simulation-based pharmaceutical education, where no patients are present, promotes visually, aurally, and tactilely simulated learning regarding the evaluation of vital signs and implementation of physical assessment when disease symptoms are present or adverse effects occur. A patient simulator also promotes the creation of training programs for emergency and critical care, with which basic as well as advanced life support can be practiced. In addition, an advanced objective structured clinical examination (OSCE) trial has been implemented to evaluate skills regarding vital signs and physical assessments. Pharmacists are required to examine vital signs and conduct physical assessment from a pharmaceutical point of view. The introduction of these pharmacy clinical skills will improve the efficacy of drugs, work for the prevention or early detection of adverse effects, and promote the appropriate use of drugs. It is considered that simulation-based pharmaceutical education is essential to understand physical assessment, and such education will ideally be applied and developed according to on-site practices.

Distribution and expression characteristics of triterpenoids and OSC genes in white birch (Betula platyphylla suk.).

PubMed

Yin, Jing; Ren, Chun-Lin; Zhan, Ya-Guang; Li, Chun-Xiao; Xiao, Jia-Lei; Qiu, Wei; Li, Xin-Yu; Peng, Hong-Mei

2012-03-01

Betulin and oleanolic acids (pentacyclic triterpenoid secondary metabolites) have broad pharmacological activities and can be potentially used for the development of anti-cancer and anti-AIDS drugs. In this study, we detected the accumulation and the distribution characteristics of betulin and oleanolic acid in various organs of white birch at different ages. We also determined the expression of 4 OSC genes (LUS, β-AS, CAS1 and CAS2) involved in the triterpenoid synthesis pathways by real time RT-PCR. The result showed that the 1-year old birch can synthesize betulin and oleanolic acid. In addition, betulin and oleanolic acids were mainly distributed in the bark, while the content in the root skin and leaf was very low. The content of betulin and oleanolic acid in birch varied in different seasons. The content of betulin and oleanolic acid and their corresponding LUS and β-AS gene expression were very low in 1-year old birch. With increasing age of birch, betulin content was increased, while oleanolic acid was decreased. Similar changes were also observed for their corresponding synthesis genes LUS and β-AS. In the leaf of 1-year old plant, the highest expression of CAS1 and CAS2 occurred at end of September, while expression of LUS and the β-AS was low from June to October. In the stem skin,high expression of β-AS and the LUS genes occurred from the end of July to September. In the root, high expression of the β-AS gene was observed at the end of October. These results indicated that triterpenoid gene expression was similar to the triterpene accumulation. Expression of LUS gene and β-AS gene in birch with different ages were corresponding to the betulinic and oleanolic acid accumulation. Expression of CAS1 and CAS2 genes were elevated with increasing age of birch. This study provides molecular mechanisms of triterpenes synthesis in birch plants.

Cloning and Functional Characterization of Three Branch Point Oxidosqualene Cyclases from Withania somnifera (L.) Dunal*

PubMed Central

Dhar, Niha; Rana, Satiander; Razdan, Sumeer; Bhat, Wajid Waheed; Hussain, Aashiq; Dhar, Rekha S.; Vaishnavi, Samantha; Hamid, Abid; Vishwakarma, Ram; Lattoo, Surrinder K.

2014-01-01

Oxidosqualene cyclases (OSCs) positioned at a key metabolic subdividing junction execute indispensable enzymatic cyclization of 2,3-oxidosqualene for varied triterpenoid biosynthesis. Such branch points present favorable gene targets for redirecting metabolic flux toward specific secondary metabolites. However, detailed information regarding the candidate OSCs covering different branches and their regulation is necessary for the desired genetic manipulation. The aim of the present study, therefore, was to characterize members of OSC superfamily from Withania somnifera (Ws), a medicinal plant of immense repute known to synthesize a large array of biologically active steroidal lactone triterpenoids called withanolides. Three full-length OSC cDNAs, β-amyrin synthase (WsOSC/BS), lupeol synthase (WsOSC/LS), and cycloartenol synthase (WsOSC/CS), having open reading frames of 2289, 2268, and 2277 bp, were isolated. Heterologous expression in Schizosaccharomyces pombe, LC-MS analyses, and kinetic studies confirmed their monofunctionality. The three WsOSCs were found to be spatially regulated at transcriptional level with WsOSC/CS being maximally expressed in leaf tissue. Promoter analysis of three WsOSCs genes resulted in identification of distinct cis-regulatory elements. Further, transcript profiling under methyl jasmonate, gibberellic acid, and yeast extract elicitations displayed differential transcriptional regulation of each of the OSCs. Changes were also observed in mRNA levels under elicitations and further substantiated with protein expression levels by Western blotting. Negative regulation by yeast extract resulted in significant increase in withanolide content. Empirical evidence suggests that repression of competitive branch OSCs like WsOSC/BS and WsOSC/LS possibly leads to diversion of substrate pool toward WsOSC/CS for increased withanolide production. PMID:24770414

Standardization of Clinical Skill Evaluation in Physical/Occupational Therapist Education –Effects of Introduction of an Education System Using OSCE–

PubMed Central

Sakurai, Hiroaki; Kanada, Yoshikiyo; Sugiura, Yoshito; Motoya, Ikuo; Yamada, Masayuki; Tomita, Masao; Naka, Toru; Teranishi, Toshio; Tanabe, Shigeo; Tsujimura, Toru; Okanishi, Tetsuo

2013-01-01

[Purpose] A major issue in physical/occupational therapist education is the improvement of students' clinical techniques. In this study, we introduced an education system using an Objective Structured Clinical Examination (OSCE), and made an attempt at standardization of its evaluation. [Subjects] The subjects were 227 students in the classes of 2008 to 2010 who enrolled at our university between 2004 and 2006, before the introduction of the education system using OSCE, and 221 students in the classes of 2011 to 2013 who enrolled between 2007 and 2009, after the introduction. [Methods] Performances in attitude and skills (performance in clinical training and OSCE) were compared between before and after the introduction of OSCE. OSCE results were compared between before and after clinical trainings at each OSCE Level; and the correlation of between performances in clinical training and OSCE was examined. [Results] Performances in OSCE and clinical training (attitude, skills) were improved by the introduction of the education system using OSCE, but no significant correlation was observed in the relationship between performances in OSCE and clinical training. [Conclusion] Further studies should be conducted aiming at the standardization of clinical skill evaluation in postgraduate education to establish an education system using OSCE. PMID:24259918

Long-term effectiveness of patient-centered training in cultural competence: what is retained? What is lost?

PubMed

Ho, Ming-Jung; Yao, Grace; Lee, Keng-Lin; Hwang, Tzung-Jeng; Beach, Mary Catherine

2010-04-01

To determine whether the effects of a patient-centered cultural competence curriculum could be sustained for one year. In 2006, 57 fifth-year medical students at National Taiwan University were randomly assigned either to a group that received training in patient-centered cross-cultural communication skills or one that received no training. Students' scores on objective structured clinical exams (OSCEs) were compared in the realms of exploring (1) patient perspectives and (2) social factors related to illness, immediately after training (OSCE1) and one year after training (OSCE2). Regarding students' exploration of patient perspectives, the intervention group scored significantly higher than the control group at OSCE1, but there was a significant decrease from OSCE1 to OSCE2 in the intervention group and no significant difference between the intervention and control group at OSCE2. Regarding students' exploration of social factors related to illness, the intervention group scored significantly higher than the control group at OSCE1, with a nonsignificant decrease from OSCE1 to OSCE2 in the two groups, such that the intervention group again scored higher than the control group in OSCE2. The effect of a patient-centered cultural competence training curriculum on students' exploration of social factors related to illness was sustained to a significant degree after one year, whereas the effects on students' exploration of patient perspectives were not. Further research is needed to determine the extent to which additional training can prevent the loss of student skills.

32 CFR 516.72 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... requested by OSC for an interview will be made available in accordance with arrangements the Labor Counselor... witnesses are aware of their obligation to answer OSC questions, their potential to be considered “suspects” in OSC investigations, and their right to the assistance of counsel during interviews with OSC...

32 CFR 516.72 - Procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... requested by OSC for an interview will be made available in accordance with arrangements the Labor Counselor... witnesses are aware of their obligation to answer OSC questions, their potential to be considered “suspects” in OSC investigations, and their right to the assistance of counsel during interviews with OSC...

Sequential Objective Structured Clinical Examination based on item response theory in Iran.

PubMed

Hejri, Sara Mortaz; Jalili, Mohammad

2017-01-01

In a sequential objective structured clinical examination (OSCE), all students initially take a short screening OSCE. Examinees who pass are excused from further testing, but an additional OSCE is administered to the remaining examinees. Previous investigations of sequential OSCE were based on classical test theory. We aimed to design and evaluate screening OSCEs based on item response theory (IRT). We carried out a retrospective observational study. At each station of a 10-station OSCE, the students' performance was graded on a Likert-type scale. Since the data were polytomous, the difficulty parameters, discrimination parameters, and students' ability were calculated using a graded response model. To design several screening OSCEs, we identified the 5 most difficult stations and the 5 most discriminative ones. For each test, 5, 4, or 3 stations were selected. Normal and stringent cut-scores were defined for each test. We compared the results of each of the 12 screening OSCEs to the main OSCE and calculated the positive and negative predictive values (PPV and NPV), as well as the exam cost. A total of 253 students (95.1%) passed the main OSCE, while 72.6% to 94.4% of examinees passed the screening tests. The PPV values ranged from 0.98 to 1.00, and the NPV values ranged from 0.18 to 0.59. Two tests effectively predicted the results of the main exam, resulting in financial savings of 34% to 40%. If stations with the highest IRT-based discrimination values and stringent cut-scores are utilized in the screening test, sequential OSCE can be an efficient and convenient way to conduct an OSCE.

Mental health and learning disability nursing students' perceptions of the usefulness of the objective structured clinical examination to assess their competence in medicine administration.

PubMed

Hemingway, Steve; Stephenson, John; Roberts, Bronwyn; McCann, Terence

2014-08-01

The aim of this study was to evaluate mental health and learning disability nursing students' perceptions of the usefulness of the objective structured clinical examination (OSCE) in assessing their administration of medicine competence. Learning disability (n = 24) and mental health (n = 46) students from a single cohort were invited to evaluate their experience of the OSCE. A 10-item survey questionnaire was used, comprising open- and closed-response questions. Twelve (50%) learning disability and 32 (69.6%) mental health nursing students participated. The OSCE was rated highly compared to other theoretical assessments; it was also reported as clinically real and as a motivational learning strategy. However, it did not rate as well as clinical practice. Content analysis of written responses identified four themes: (i) benefits of the OSCE; (ii) suggestions to improve the OSCE; (iii) concern about the lack of clinical reality of the OSCE; and (iv) OSCE-induced stress. The themes, although repeating some of the positive statistical findings, showed that participants were critical of the university setting as a place to conduct clinical assessment, highlighted OSCE-related stress, and questioned the validity of the OSCE as a real-world assessment. The OSCE has an important role in the development of student nurses' administration of medicine skills. However, it might hinder their performance as a result of the stress of being assessed in a simulated environment.

Does studying for an objective structured clinical examination make a difference?

PubMed

Mavis, B E

2000-10-01

This study examines the extent to which second-year medical students studied for an objective structured clinical examination (OSCE), how they studied, and the impact of self-reported studying on OSCE performance. One class of 113 medical students completed an end-of-second-year OSCE, held on two consecutive evenings. The OSCE was comprised of eight stations, each of which was of 20 minutes' duration. The OSCE was formative: students received performance feedback but were not graded. Prior to the OSCE, students completed a brief survey regarding their preparation for the OSCE and their perceptions of confidence, anxiety and preparedness. Only 78 students returned surveys with names, comprising the data for these analyses. Mean studying time was 3.3 h, ranging from 0 to 19 h. Studying time was positively associated with age and negatively associated with basic science examination scores. The most study time was dedicated to reviewing the physical examination textbook, class notes and supplemental course readings. The breadth of study strategies increased as more time was spent in OSCE preparation. OSCE performance was related to study time and to achievement on pre-clinical basic science examinations. The students whose performance was above average seemed to be the talented students whose records indicated a history of academic success. The amount of time they reported for OSCE preparation was comparable to that reported by students with below average performance. It appears that prior academic performance rather than preparatory studying time is a better predictor of OSCE outcomes.

One-Stop Clinic Utilization in Plastic Surgery: Our Local Experience and the Results of a UK-Wide National Survey.

PubMed

Gorman, Mark; Coelho, James; Gujral, Sameer; McKay, Alastair

2015-01-01

Introduction. "See and treat" one-stop clinics (OSCs) are an advocated NHS initiative to modernise care, reducing cancer treatment waiting times. Little studied in plastic surgery, the existing evidence suggests that though they improve care, they are rarely implemented. We present our experience setting up a plastic surgery OSC for minor skin surgery and survey their use across the UK. Methods. The OSC was evaluated by 18-week wait target compliance, measures of departmental capacity, and patient satisfaction. Data was obtained from 32 of the 47 UK plastic surgery departments to investigate the prevalence of OSCs for minor skin cancer surgery. Results. The OSC improved 18-week waiting times, from a noncompliant mean of 80% to a compliant 95% average. Department capacity increased 15%. 95% of patients were highly satisfied with and preferred the OSC to a conventional service. Only 25% of UK plastic surgery units run OSCs, offering varying reasons for not doing so, 42% having not considered their use. Conclusions. OSCs are underutilised within UK plastic surgery, where a significant proportion of units have not even considered their benefit. This is despite associated improvements in waiting times, department capacity, and levels of high patient satisfaction. We offer our considerations and local experience instituting an OSC service.

One-Stop Clinic Utilization in Plastic Surgery: Our Local Experience and the Results of a UK-Wide National Survey

PubMed Central

Gorman, Mark; Coelho, James; Gujral, Sameer; McKay, Alastair

2015-01-01

Introduction. “See and treat” one-stop clinics (OSCs) are an advocated NHS initiative to modernise care, reducing cancer treatment waiting times. Little studied in plastic surgery, the existing evidence suggests that though they improve care, they are rarely implemented. We present our experience setting up a plastic surgery OSC for minor skin surgery and survey their use across the UK. Methods. The OSC was evaluated by 18-week wait target compliance, measures of departmental capacity, and patient satisfaction. Data was obtained from 32 of the 47 UK plastic surgery departments to investigate the prevalence of OSCs for minor skin cancer surgery. Results. The OSC improved 18-week waiting times, from a noncompliant mean of 80% to a compliant 95% average. Department capacity increased 15%. 95% of patients were highly satisfied with and preferred the OSC to a conventional service. Only 25% of UK plastic surgery units run OSCs, offering varying reasons for not doing so, 42% having not considered their use. Conclusions. OSCs are underutilised within UK plastic surgery, where a significant proportion of units have not even considered their benefit. This is despite associated improvements in waiting times, department capacity, and levels of high patient satisfaction. We offer our considerations and local experience instituting an OSC service. PMID:26236502

Assessment of first-year post-graduate residents: usefulness of multiple tools.

PubMed

Yang, Ying-Ying; Lee, Fa-Yauh; Hsu, Hui-Chi; Huang, Chin-Chou; Chen, Jaw-Wen; Cheng, Hao-Min; Lee, Wen-Shin; Chuang, Chiao-Lin; Chang, Ching-Chih; Huang, Chia-Chang

2011-12-01

Objective Structural Clinical Examination (OSCE) usually needs a large number of stations with long test time, which usually exceeds the resources available in a medical center. We aimed to determine the reliability of a combination of Direct Observation of Procedural Skills (DOPS), Internal Medicine in-Training Examination (IM-ITE(®)) and OSCE, and to verify the correlation between the small-scale OSCE+DOPS+IM-ITE(®)-composited scores and 360-degree evaluation scores of first year post-graduate (PGY(1)) residents. Between 2007 January to 2010 January, two hundred and nine internal medicine PGY1 residents completed DOPS, IM-ITE(®) and small-scale OSCE at our hospital. Faculty members completed 12-item 360-degree evaluation for each of the PGY(1) residents regularly. The small-scale OSCE scores correlated well with the 360-degree evaluation scores (r = 0.37, p < 0.021). Interestingly, the addition of DOPS scores to small-scale OSCE scores [small-scale OSCE+DOPS-composited scores] increased it's correlation with 360-degree evaluation scores of PGY(1) residents (r = 0.72, p < 0.036). Further, combination of IM-ITE(®) score with small-scale OSCE+DOPS scores [small-scale OSCE+DOPS+IM-ITE(®)-composited scores] markedly enhanced their correlation with 360-degree evaluation scores (r = 0.85, p < 0.016). The strong correlations between 360-degree evaluation and small-scale OSCE+DOPS+IM-ITE(®)-composited scores suggested that both methods were measuring the same quality. Our results showed that the small-scale OSCE, when associated with both the DOPS and IM-ITE(®), could be an important assessment method for PGY(1) residents. Copyright © 2011. Published by Elsevier B.V.

Fill factor in organic solar cells can exceed the Shockley-Queisser limit

NASA Astrophysics Data System (ADS)

Trukhanov, Vasily A.; Bruevich, Vladimir V.; Paraschuk, Dmitry Yu.

2015-06-01

The ultimate efficiency of organic solar cells (OSC) is under active debate. The solar cell efficiency is calculated from the current-voltage characteristic as a product of the open-circuit voltage (VOC), short-circuit current (JSC), and the fill factor (FF). While the factors limiting VOC and JSC for OSC were extensively studied, the ultimate FF for OSC is scarcely explored. Using numerical drift-diffusion modeling, we have found that the FF in OSC can exceed the Shockley-Queisser limit (SQL) established for inorganic p-n junction solar cells. Comparing charge generation and recombination in organic donor-acceptor bilayer heterojunction and inorganic p-n junction, we show that such distinctive properties of OSC as interface charge generation and heterojunction facilitate high FF, but the necessary condition for FF exceeding the SQL in OSC is field-dependence of charge recombination at the donor-acceptor interface. These findings can serve as a guideline for further improvement of OSC.

Measuring Professional Behaviour in Canadian Physical Therapy Students' Objective Structured Clinical Examinations: An Environmental Scan

PubMed Central

Ellerton, Cindy; Evans, Cathy

2015-01-01

ABSTRACT Purpose: To identify professional behaviours measured in objective structured clinical examinations (OSCEs) by Canadian university physical therapy (PT) programs. Method: A cross-sectional telephone survey was conducted to review current practice and determine which OSCE items Canadian PT programs are using to measure PT students' professional behaviours. Telephone interviews using semi-structured questions were conducted with individual instructors responsible for courses that included an OSCE as part of the assessment component. Results: Nine PT programmes agreed to take part in the study, and all reported conducting at least one OSCE. The number and characteristics of OSCEs varied both within and across programs. Participants identified 31 professional behaviour items for use in an OSCE; these items clustered into four categories: communication (n=14), respect (n=10), patient safety (n=4), and physical therapists' characteristics (n=3). Conclusions: All Canadian entry-level PT programmes surveyed assess professional behaviours in OSCE-type examinations; however, the content and style of assessment is variable. The local environment should be considered when determining what professional behaviours are appropriate to assess in the OSCE context in individual programmes. PMID:25931656

76 FR 68432 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

... the Organization for Security and Cooperation in Europe (OSCE) and in early 1995 assumed the co-chairmanship of the OSCE's Minsk Group on the Nagorno-Karabakh conflict. Finland chaired the OSCE in 2008 and...

5 CFR 1820.1 - General provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... records is available on the FOIA page of OSC's Web site (http://www.osc.gov/foia.htm). Information... by the public affairs officer, records published on the agency's Web site (http://www.osc.gov), or...

5 CFR 1820.1 - General provisions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... records is available on the FOIA page of OSC's Web site (http://www.osc.gov/foia.htm). Information... by the public affairs officer, records published on the agency's Web site (http://www.osc.gov), or...

5 CFR 1820.1 - General provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... records is available on the FOIA page of OSC's Web site (http://www.osc.gov/foia.htm). Information... by the public affairs officer, records published on the agency's Web site (http://www.osc.gov), or...

Computer assisted Objective structured clinical examination versus Objective structured clinical examination in assessment of Dermatology undergraduate students.

PubMed

Chaudhary, Richa; Grover, Chander; Bhattacharya, S N; Sharma, Arun

2017-01-01

The assessment of dermatology undergraduates is being done through computer assisted objective structured clinical examination at our institution for the last 4 years. We attempted to compare objective structured clinical examination (OSCE) and computer assisted objective structured clinical examination (CA-OSCE) as assessment tools. To assess the relative effectiveness of CA-OSCE and OSCE as assessment tools for undergraduate dermatology trainees. Students underwent CA-OSCE as well as OSCE-based evaluation of equal weightage as an end of posting assessment. The attendance as well as the marks in both the examination formats were meticulously recorded and statistically analyzed using SPSS version 20.0. Intercooled Stata V9.0 was used to assess the reliability and internal consistency of the examinations conducted. Feedback from both students and examiners was also recorded. The mean attendance for the study group was 77% ± 12.0%. The average score on CA- OSCE and OSCE was 47.4% ± 19.8% and 53.5% ± 18%, respectively. These scores showed a mutually positive correlation, with Spearman's coefficient being 0.593. Spearman's rank correlation coefficient between attendance scores and assessment score was 0.485 for OSCE and 0.451 for CA-OSCE. The Cronbach's alpha coefficient for all the tests ranged from 0.76 to 0.87 indicating high reliability. The comparison was based on a single batch of 139 students. Such an evaluation on more students in larger number of batches over successive years could help throw more light on the subject. Computer assisted objective structured clinical examination was found to be a valid, reliable and effective format for dermatology assessment, being rated as the preferred format by examiners.

A focus group study of the use of video-recorded simulated objective structured clinical examinations in nurse practitioner education.

PubMed

Barratt, Julian

2010-05-01

The objective structured clinical examination (OSCE) is a common method of clinical skills assessment used for advanced nurse practitioner students across the United Kingdom. The purpose of an advanced nursing OSCE is to assess a nurse practitioner student's competence and safety in the performance of commonly used advanced clinical practice skills. Students often feel nervous when preparing for and participating in an OSCE. Consideration of these identified anxieties led to the development of an alternative method of meeting students' OSCE learning and preparation needs; namely video-recorded simulated OSCEs. Video-recording was appealing for the following reasons: it provides a flexible usage of staff resources and time; OSCE performance mistakes can be rectified; it is possible to use the same video-recordings with multiple cohorts of students, and the recordings can be made conveniently available for students with video streaming on internet-based video-sharing sites or virtual learning environments. The aim of the study was to explore the value of using such recordings amongst nurse practitioner students, via online and face-to-face focus groups, to see if they are a suitable OSCE educational preparation technique. The study findings indicate that simulated OSCE video-recordings are an effective method for supporting nurse practitioner educational development. Copyright 2009 Elsevier Ltd. All rights reserved.

Evaluation of Clinical and Communication Skills of Pharmacy Students and Pharmacists with an Objective Structured Clinical Examination.

PubMed

Urteaga, Elizabeth M; Attridge, Rebecca L; Tovar, John M; Witte, Amy P

2015-10-25

Objective. To evaluate how effectively pharmacy students and practicing pharmacists communicate and apply knowledge to simulations of commonly encountered patient scenarios using an objective structured clinical examination (OSCE). Design. Second-, third-, and fourth-year pharmacy students completed an OSCE as part of their required courses in 2012 and 2013. All students in both years completed identical OSCE cases. Licensed pharmacists were recruited to complete the OSCE and serve as controls in 2012. A survey assessed student perception and acceptance of the OSCE as well as student confidence in performance. Assessment. Licensed pharmacists had significantly higher clinical and communication skills scores than did pharmacy students. Student progression in communication and clinical skills improved significantly over time. Survey results indicated that students felt the OSCE was well-structured and assessed clinical skills taught in pharmacy school; 86% of students felt confident they could provide these skills. Conclusion. Objective structured clinical examinations can evaluate clinical competence and communication skills among professional students. Implementation of OSCEs may be an effective tool for assessment of the Center for the Advancement of Pharmacy Education domains.

An unusual plant triterpene synthase with predominant α-amyrin-producing activity identified by characterizing oxidosqualene cyclases from Malus × domestica.

PubMed

Brendolise, Cyril; Yauk, Yar-Khing; Eberhard, Ellen D; Wang, Mindy; Chagne, David; Andre, Christelle; Greenwood, David R; Beuning, Lesley L

2011-07-01

The pentacyclic triterpenes, in particular ursolic acid and oleanolic acid and their derivatives, exist abundantly in the plant kingdom, where they are well known for their anti-inflammatory, antitumour and antimicrobial properties. α-Amyrin and β-amyrin are the precursors of ursolic and oleanolic acids, respectively, formed by concerted cyclization of squalene epoxide by a complex synthase reaction. We identified three full-length expressed sequence tag sequences in cDNA libraries constructed from apple (Malus × domestica 'Royal Gala') that were likely to encode triterpene synthases. Two of these expressed sequence tag sequences were essentially identical (> 99% amino acid similarity; MdOSC1 and MdOSC3). MdOSC1 and MdOSC2 were expressed by transient expression in Nicotiana benthamiana leaves and by expression in the yeast Pichia methanolica. The resulting products were analysed by GC and GC-MS. MdOSC1 was shown to be a mixed amyrin synthase (a 5 : 1 ratio of α-amyrin to β-amyrin). MdOSC1 is the only triterpene synthase so far identified in which the level of α-amyrin produced is > 80% of the total product and is, therefore, primarily an α-amyrin synthase. No product was evident for MdOSC2 when expressed either transiently or in yeast, suggesting that this putative triterpene synthase is either encoded by a pseudogene or does not express well in these systems. Transcript expression analysis in Royal Gala indicated that the genes are mostly expressed in apple peel, and that the MdOSC2 expression level was much lower than that of MdOSC1 and MdOSC3 in all the tissues tested. Amyrin content analysis was undertaken by LC-MS, and demonstrated that levels and ratios differ between tissues, but that the true consequence of synthase activity is reflected in the ursolic/oleanolic acid content and in further triterpenoids derived from them. Phylogenetic analysis placed the three triterpene synthase sequences with other triterpene synthases that encoded either �

The method used to set the pass mark in an objective structured clinical examination defines the performance of candidates for certification as rheumatologists.

PubMed

Pascual-Ramos, Virginia; Guilaisne Bernard-Medina, Ana; Flores-Alvarado, Diana Elsa; Portela-Hernández, Margarita; Maldonado-Velázquez, María Del Rocío; Jara-Quezada, Luis Javier; Amezcua-Guerra, Luis Manuel; Rubio-Judith López-Zepeda, Nadina E; Álvarez-Hernandez, Everardo; Saavedra, Miguel Ángel; Arce-Salinas, César Alejandro

The Mexican Accreditation Council for Rheumatology certifies trainees (TR) on an annual basis using both a multiple-choice question (MCQ) test and an objective structured clinical examination (OSCE). For 2013 and 2014, the OSCE pass mark (PM) was set by criterion referencing as ≥6 (CPM), whereas overall rating of borderline performance method (BPM) was added for 2015 and 2016 accreditations. We compared OSCE TR performance according to CPM and BPM, and examined whether correlations between MCQ and OSCE were affected by PM. Forty-three (2015) and 37 (2016) candidates underwent both tests. Altogether, OSCE were integrated by 15 validated stations; one evaluator per station scored TR performance according to a station-tailored check-list and a Likert scale (fail, borderline, above range) of overall performance. A composite OSCE score was derived for each candidate. Appropriate statistics were used. Mean (±standard derivation [SD]) MCQ test scores were 6.6±0.6 (2015) and 6.4±0.6 (2016) with 5 candidates receiving a failing score each year. Mean (±SD) OSCE scores were 7.4±0.6 (2015) and 7.3±0.6 (2016); no candidate received a failing CPM score in either 2015 or 2016 OSCE, although 21 (49%) and 19 (51%) TR, respectively, received a failing BPM score (calculated as 7.3 and 7.4, respectively). Stations for BPM ranged from 4.5 to 9.5; overall, candidates showed better performance in CPM. In all, MCQ correlated with composite OSCE, r=0.67 (2015) and r=0.53 (2016); P≤.001. Trainees with a passing BPM score in OSCE had higher MCQ scores than those with a failing score. Overall, OSCE-PM selection impacted candidates' performance but had a limited affect on correlation between clinical and practical examinations. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Use of online clinical videos for clinical skills training for medical students: benefits and challenges.

PubMed

Jang, Hye Won; Kim, Kyong-Jee

2014-03-21

Multimedia learning has been shown effective in clinical skills training. Yet, use of technology presents both opportunities and challenges to learners. The present study investigated student use and perceptions of online clinical videos for learning clinical skills and in preparing for OSCE (Objective Structured Clinical Examination). This study aims to inform us how to make more effective us of these resources. A mixed-methods study was conducted for this study. A 30-items questionnaire was administered to investigate student use and perceptions of OSCE videos. Year 3 and 4 students from 34 Korean medical schools who had access to OSCE videos participated in the online survey. Additionally, a semi-structured interview of a group of Year 3 medical students was conducted for an in-depth understanding of student experience with OSCE videos. 411 students from 31 medical schools returned the questionnaires; a majority of them found OSCE videos effective for their learning of clinical skills and in preparing for OSCE. The number of OSCE videos that the students viewed was moderately associated with their self-efficacy and preparedness for OSCE (p < 0.05). One-thirds of those surveyed accessed the video clips using mobile devices; they agreed more with the statement that it was convenient to access the video clips than their peers who accessed the videos using computers (p < 0.05). Still, students reported lack of integration into the curriculum and lack of interaction as barriers to more effective use of OSCE videos. The present study confirms the overall positive impact of OSCE videos on student learning of clinical skills. Having faculty integrate these learning resources into their teaching, integrating interactive tools into this e-learning environment to foster interactions, and using mobile devices for convenient access are recommended to help students make more effective use of these resources.

Association of the pre-internship objective structured clinical examination in final year medical students with comprehensive written examinations.

PubMed

Eftekhar, Hasan; Labaf, Ali; Anvari, Pasha; Jamali, Arsia; Sheybaee-Moghaddam, Farshad

2012-01-01

The purpose of this study is to evaluate the association of the pre-internship Objective Structured Clinical Examination (OSCE) in final year medical students with comprehensive written examinations. SUBJECTS AND MATERIAL: All medical students of October 2004 admission who took part in the October 2010 National Comprehensive Pre-internship Examination (NCPE) and pre-internship OSCE were included in the study (n = 130). OSCE and NCPE scores and medical grade point average (GPA) were collected. GPA was highly correlated with NCPE (r = 0.76 and P<0.001) and moderately with OSCE (r = 0.68 and P < 0.001). Similarly a moderate correlation was observed between NCPE and OSCE scores(r = 0.6 and P < 0.001).Linear stepwise regression shows r(2) of a model applying GPA as predictor of OSCE score is 0.46 (β = 0.68 and P < 0.001), while addition of gender to the model increases r(2) to 0.59 (β = 0.61 and 0.36, for GPA and male gender, respectively and P < 0.001). Logistic forward regression models shows male gender and GPA are the only dependent predictors of high score in OSCE. OR of GPA and male gender for high OSCE score are 4.89 (95% CI = 2.37-10.06) and 6.95 (95% CI = 2.00-24.21), respectively (P < 0.001). Our findings indicate OSCE and examination which mainly evaluate knowledge, judged by GPA and NCPE are moderately to highly correlated. Our results illustrate the interwoven nature of knowledge and clinical skills. In other words, certain level of knowledge is crucial for appropriate clinical performance. Our findings suggest neither OSCE nor written forms of assessments can replace each other. They are complimentary and should also be combined by other evaluations to cover all attributes of clinical competence efficiently.

Association of the pre-internship objective structured clinical examination in final year medical students with comprehensive written examinations

PubMed Central

Eftekhar, Hasan; Labaf, Ali; Anvari, Pasha; Jamali, Arsia; Sheybaee-Moghaddam, Farshad

2012-01-01

Aim The purpose of this study is to evaluate the association of the pre-internship Objective Structured Clinical Examination (OSCE) in final year medical students with comprehensive written examinations. Subjects and material All medical students of October 2004 admission who took part in the October 2010 National Comprehensive Pre-internship Examination (NCPE) and pre-internship OSCE were included in the study (n=130). OSCE and NCPE scores and medical grade point average (GPA) were collected. Results GPA was highly correlated with NCPE (r=0.76 and P<0.001) and moderately with OSCE (r=0.68 and P<0.001). Similarly a moderate correlation was observed between NCPE and OSCE scores(r=0.6 and P<0.001).Linear stepwise regression shows r 2 of a model applying GPA as predictor of OSCE score is 0.46 (β=0.68 and P<0.001), while addition of gender to the model increases r 2 to 0.59 (β=0.61 and 0.36, for GPA and male gender, respectively and P<0.001). Logistic forward regression models shows male gender and GPA are the only dependent predictors of high score in OSCE. OR of GPA and male gender for high OSCE score are 4.89 (95% CI=2.37–10.06) and 6.95 (95% CI=2.00–24.21), respectively (P<0.001). Discussion Our findings indicate OSCE and examination which mainly evaluate knowledge, judged by GPA and NCPE are moderately to highly correlated. Our results illustrate the interwoven nature of knowledge and clinical skills. In other words, certain level of knowledge is crucial for appropriate clinical performance. Our findings suggest neither OSCE nor written forms of assessments can replace each other. They are complimentary and should also be combined by other evaluations to cover all attributes of clinical competence efficiently. PMID:22547924

Influences of semiconductor morphology on the mechanical fatigue behavior of flexible organic electronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Young-Joo; Yeon, Han-Wool; Shin, Hae-A-Seul

2013-12-09

The influence of crystalline morphology on the mechanical fatigue of organic semiconductors (OSCs) was investigated using 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) as a crystalline OSC and poly(triarylamine) (PTAA) as an amorphous OSC. During cyclic bending, resistances of the OSCs were monitored using the transmission-line method on a metal-semiconductor-metal structure. The resistance of the TIPS-pentacene increased under fatigue damage in tensile-stress mode, but no such degradation was observed in the PTAA. Both OSCs were stable under compressive bending fatigue. The formation of intergranular cracks at the domain boundaries of the TIPS-pentacene was responsible for the degradation of its electrical properties under tensile bending fatigue.

Sensitive detection of oversulfated chondroitin sulfate in heparin sodium or crude heparin with a colorimetric microplate based assay.

PubMed

Sommers, Cynthia D; Mans, Daniel J; Mecker, Laura C; Keire, David A

2011-05-01

In this work we describe a 96-well microplate assay for oversulfated chondroitin sulfate A (OSCS) in heparin, based on a water-soluble cationic polythiophene polymer (3-(2-(N-(N'-methylimidazole))ethoxy)-4-methylthiophene (LPTP)) and heparinase digestion of heparin. The assay takes advantage of several unique properties of heparin, OSCS, and LPTP, including OSCS inhibition of heparinase I and II activity, the molecular weight dependence of heparin-LPTP spectral shifts, and the distinct association of heparin fragments and OSCS to LPTP. These factors combine to enable detection of the presence of 0.003% w/w spiked OSCS in 10 μg of heparin sodium active pharmaceutical ingredient (API) using a plate reader and with visual detection to 0.1% levels. The same detection limit for OSCS was observed in the presence of 10% levels of dermatan sulfate (DS) or chondroitin sulfate A (CSA) impurities. In addition, we surveyed a selection of crude heparin samples received by the agency in 2008 and 2009 to determine average and extreme DS, CSA, and galactosamine weight percent levels. In the presence of these impurities and the variable heparin content in the crude heparin samples, spiked OSCS was reliably detected to the 0.1% w/w level using a plate reader. Finally, authentically OSCS contaminated heparin sodium API and crude samples were distinguished visually by color from control samples using the LPTP/heparinase test.

Hot kinetic model as a guide to improve organic photovoltaic materials.

PubMed

Sosorev, Andrey Yu; Godovsky, Dmitry Yu; Paraschuk, Dmitry Yu

2018-01-31

The modeling of organic solar cells (OSCs) can provide a roadmap for their further improvement. Many OSC models have been proposed in recent years; however, the impact of the key intermediates from photons to electricity-hot charge-transfer (CT) states-on the OSC efficiency is highly ambiguous. In this study, we suggest an analytical kinetic model for OSC that considers a two-step charge generation via hot CT states. This hot kinetic model allowed us to evaluate the impact of different material parameters on the OSC performance: the driving force for charge separation, optical bandgap, charge mobility, geminate recombination rate, thermalization rate, average electron-hole separation distance in the CT state, dielectric permittivity, reorganization energy and charge delocalization. In contrast to a widespread trend of lowering the material bandgap, the model predicts that this approach is only efficient along with improvement of the other material properties. The most promising ways to increase the OSC performance are decreasing the reorganization energy, i.e., an energy change accompanying CT from the donor molecule to the acceptor, increasing the dielectric permittivity and charge delocalization. The model suggests that there are no fundamental limitations that can prevent achieving the OSC efficiency above 20%.

32 CFR Appendix to Part 145 - Legal Representation

Code of Federal Regulations, 2011 CFR

2011-07-01

... obligations. This includes assistance at any interviews with OSC investigators. However, the attorney-client... accuracy in responding to an OSC interviewer's questions. b. Requests for clarification of both questions... interview by OSC investigators are appropriate, whether the employee is or is not accompanied by a legal...

32 CFR Appendix to Part 145 - Legal Representation

Code of Federal Regulations, 2010 CFR

2010-07-01

... obligations. This includes assistance at any interviews with OSC investigators. However, the attorney-client... accuracy in responding to an OSC interviewer's questions. b. Requests for clarification of both questions... interview by OSC investigators are appropriate, whether the employee is or is not accompanied by a legal...

Fast charge separation in a non-fullerene organic solar cell with a small driving force

NASA Astrophysics Data System (ADS)

Liu, Jing; Chen, Shangshang; Qian, Deping; Gautam, Bhoj; Yang, Guofang; Zhao, Jingbo; Bergqvist, Jonas; Zhang, Fengling; Ma, Wei; Ade, Harald; Inganäs, Olle; Gundogdu, Kenan; Gao, Feng; Yan, He

2016-07-01

Fast and efficient charge separation is essential to achieve high power conversion efficiency in organic solar cells (OSCs). In state-of-the-art OSCs, this is usually achieved by a significant driving force, defined as the offset between the bandgap (Egap) of the donor/acceptor materials and the energy of the charge transfer (CT) state (ECT), which is typically greater than 0.3 eV. The large driving force causes a relatively large voltage loss that hinders performance. Here, we report non-fullerene OSCs that exhibit ultrafast and efficient charge separation despite a negligible driving force, as ECT is nearly identical to Egap. Moreover, the small driving force is found to have minimal detrimental effects on charge transfer dynamics of the OSCs. We demonstrate a non-fullerene OSC with 9.5% efficiency and nearly 90% internal quantum efficiency despite a low voltage loss of 0.61 V. This creates a path towards highly efficient OSCs with a low voltage loss.

Extracting the Density of States of Copper Phthalocyanine at the SiO2 Interface with Electronic Sum Frequency Generation.

PubMed

Pandey, Ravindra; Moon, Aaron P; Bender, Jon A; Roberts, Sean T

2016-03-17

Organic semiconductors (OSCs) constitute an attractive platform for optoelectronics design due to the ease of their processability and chemically tunable properties. Incorporating OSCs into electrical circuits requires forming junctions between them and other materials, yet the change in dielectric properties about these junctions can strongly perturb the electronic structure of the OSC. Here we adapt an interface-selective optical technique, electronic sum frequency generation (ESFG), to the study of a model OSC thin-film system, copper phthalocyanine (CuPc) deposited on SiO2. We find that by modeling the thickness dependence of our measured spectra, we can identify changes in CuPc's electronic density of states at both its buried interface with SiO2 and air-exposed surface. Our work demonstrates that ESFG can be used to noninvasively probe the interfacial electronic structure of optically thick OSC films, indicating that it can be used for the study of OSC-based optoelectronics in situ.

Organic solar cells based on non-fullerene acceptors

NASA Astrophysics Data System (ADS)

Hou, Jianhui; Inganäs, Olle; Friend, Richard H.; Gao, Feng

2018-02-01

Organic solar cells (OSCs) have been dominated by donor:acceptor blends based on fullerene acceptors for over two decades. This situation has changed recently, with non-fullerene (NF) OSCs developing very quickly. The power conversion efficiencies of NF OSCs have now reached a value of over 13%, which is higher than the best fullerene-based OSCs. NF acceptors show great tunability in absorption spectra and electron energy levels, providing a wide range of new opportunities. The coexistence of low voltage losses and high current generation indicates that new regimes of device physics and photophysics are reached in these systems. This Review highlights these opportunities made possible by NF acceptors, and also discuss the challenges facing the development of NF OSCs for practical applications.

Interfacial Materials for Organic Solar Cells: Recent Advances and Perspectives

PubMed Central

Yin, Zhigang; Wei, Jiajun

2016-01-01

Organic solar cells (OSCs) have shown great promise as low‐cost photovoltaic devices for solar energy conversion over the past decade. Interfacial engineering provides a powerful strategy to enhance efficiency and stability of OSCs. With the rapid advances of interface layer materials and active layer materials, power conversion efficiencies (PCEs) of both single‐junction and tandem OSCs have exceeded a landmark value of 10%. This review summarizes the latest advances in interfacial layers for single‐junction and tandem OSCs. Electron or hole transporting materials, including metal oxides, polymers/small‐molecules, metals and metal salts/complexes, carbon‐based materials, organic‐inorganic hybrids/composites, and other emerging materials, are systemically presented as cathode and anode interface layers for high performance OSCs. Meanwhile, incorporating these electron‐transporting and hole‐transporting layer materials as building blocks, a variety of interconnecting layers for conventional or inverted tandem OSCs are comprehensively discussed, along with their functions to bridge the difference between adjacent subcells. By analyzing the structure–property relationships of various interfacial materials, the important design rules for such materials towards high efficiency and stable OSCs are highlighted. Finally, we present a brief summary as well as some perspectives to help researchers understand the current challenges and opportunities in this emerging area of research. PMID:27812480

Conductive pathway on cotton fabric created using solution with silver organometallic compound

NASA Astrophysics Data System (ADS)

Campbell, Eric E.; He, Ruijian; Mayer, Michael

2017-10-01

A knitted cotton fabric is made conductive by thermal deposition of an organometallic silver compound (OSC). For the thermal process, the fabric was soaked with the OSC liquid and heated to 225 °C for 4 min. The cured state of the OSC is determined by the stabilization in the electrical resistance. The resulting silver metallization is shaped as nanoparticles and a continuous film. A typical resistance of a 10 cm  ×  1.5 cm metallized strip made with 1.9 ml OSC is 1.70 Ω. Various other resistance levels were achieved. A higher volume of OSC provided a lower electrical resistance for the metallized conductive path but increased its stiffness. Lower resistance was achieved by increasing the number of repeat coatings while keeping the OSC volume constant. The resistance decreased when the OSC coated fabric was elongated, an effect similar to negative piezoresistivity. A resistance of initially 0.34 Ω decreased to a minimum of 0.29 Ω at 10% elongation under repeated stretching and relaxation cycling. The metallization method reported here can be suitable for applications in the field know as technical textiles, electronic textiles (e-textiles), wearable electronics, functional garments, or smart fabrics.

Health Literacy in Transitions of Care: An Innovative Objective Structured Clinical Examination for Fourth-Year Medical Students in an Internship Preparation Course.

PubMed

Bloom-Feshbach, Kimberly; Casey, Dana; Schulson, Lucy; Gliatto, Peter; Giftos, Jonathan; Karani, Reena

2016-02-01

Low health literacy is associated with adverse health outcomes, especially during transitions of care. Competency-based assessments may improve communication during this time. To develop an Objective Structured Clinical Examination (OSCE) for medical students to demonstrate communication skills to be used during the hospital discharge process with patients of low health literacy. The OSCE was integrated into the curriculum of an internship preparatory clerkship. One hundred and one fourth-year medical students participated. Students received a skills-based health literacy workshop. In the OSCE, learners counseled standardized patients regarding initiation of anticoagulation at discharge and wrote discharge instructions. Fifty-seven students completed the workshop prior to the OSCE, and 44 participated in the workshop after the completing the OSCE. Participants who completed the workshop first outperformed their peers on the checklist (15.1 vs. 13.4, p < 0.0001) and on the reading level of their written instructions (9.9 vs. 10.6, p = 0.01); 82% felt confident communicating with patients of low health literacy after the workshop and OSCE. This OSCE is a tool to train and evaluate future interns' ability to communicate with patients of limited health literacy levels at hospital discharge. Such innovations may make this period of time safer for patients, improving health outcomes.

Simultaneous determination of penicillin G salts by infrared spectroscopy: Evaluation of combining orthogonal signal correction with radial basis function-partial least squares regression

NASA Astrophysics Data System (ADS)

Talebpour, Zahra; Tavallaie, Roya; Ahmadi, Seyyed Hamid; Abdollahpour, Assem

2010-09-01

In this study, a new method for the simultaneous determination of penicillin G salts in pharmaceutical mixture via FT-IR spectroscopy combined with chemometrics was investigated. The mixture of penicillin G salts is a complex system due to similar analytical characteristics of components. Partial least squares (PLS) and radial basis function-partial least squares (RBF-PLS) were used to develop the linear and nonlinear relation between spectra and components, respectively. The orthogonal signal correction (OSC) preprocessing method was used to correct unexpected information, such as spectral overlapping and scattering effects. In order to compare the influence of OSC on PLS and RBF-PLS models, the optimal linear (PLS) and nonlinear (RBF-PLS) models based on conventional and OSC preprocessed spectra were established and compared. The obtained results demonstrated that OSC clearly enhanced the performance of both RBF-PLS and PLS calibration models. Also in the case of some nonlinear relation between spectra and component, OSC-RBF-PLS gave satisfactory results than OSC-PLS model which indicated that the OSC was helpful to remove extrinsic deviations from linearity without elimination of nonlinear information related to component. The chemometric models were tested on an external dataset and finally applied to the analysis commercialized injection product of penicillin G salts.

Bioinformatics analysis of the oxidosqualene cyclase gene and the amino acid sequence in mangrove plants

NASA Astrophysics Data System (ADS)

Basyuni, M.; Wati, R.

2017-01-01

This study described the bioinformatics methods to analyze seven oxidosqualene cyclase (OSC) genes from mangrove plants on DDBJ/EMBL/GenBank as well as predicted the structure, composition, similarity, subcellular localization and phylogenetic. The physical and chemical properties of seven mangrove OSC showed variation among the genes. The percentage of the secondary structure of seven mangrove OSC genes followed the order of a helix > random coil > extended chain structure. The values of chloroplast or signal peptide were too low, indicated that no chloroplast transit peptide or signal peptide of secretion pathway in mangrove OSC genes. The target peptide value of mitochondria varied from 0.163 to 0.430, indicated it was possible to exist. These results suggested the importance of understanding the diversity and functional of properties of the different amino acids in mangrove OSC genes. To clarify the relationship among the mangrove OSC gene, a phylogenetic tree was constructed. The phylogenetic tree shows that there are three clusters, Kandelia KcMS join with Bruguiera BgLUS, Rhizophora RsM1 was close to Bruguiera BgbAS, and Rhizophora RcCAS join with Kandelia KcCAS. The present study, therefore, supported the previous results that plant OSC genes form distinct clusters in the tree.

Triplet Tellurophene-Based Acceptors for Organic Solar Cells.

PubMed

Yang, Lei; Gu, Wenxing; Lv, Lei; Chen, Yusheng; Yang, Yufei; Ye, Pan; Wu, Jianfei; Hong, Ling; Peng, Aidong; Huang, Hui

2018-01-22

Triplet materials have been employed to achieve high-performing organic solar cells (OSCs) by extending the exciton lifetime and diffusion distances, while the triplet non-fullerene acceptor materials have never been reported for bulk heterojunction OSCs. Herein, for the first time, three triplet molecular acceptors based on tellurophene with different degrees of ring fusing were designed and synthesized for OSCs. Significantly, these molecules have long exciton lifetime and diffusion lengths, leading to efficient power conversion efficiency (7.52 %), which is the highest value for tellurophene-based OSCs. The influence of the extent of ring fusing on molecular geometry and OSCs performance was investigated to show the power conversion efficiencies (PCEs) continuously increased along with increasing the extent of ring fusing. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Used protocols for isolation and propagation of ovarian stem cells, different cells with different traits.

PubMed

Yazdekhasti, Hossein; Rajabi, Zahra; Parvari, Soraya; Abbasi, Mehdi

2016-10-20

Although existence of ovarian stem cells (OSCs) in mammalian postnatal ovary is still under controversy, however, it has been almost accepted that OSCs are contributing actively to folliculogenesis and neo-oogenesis. Recently, various methods with different efficacies have been employed for OSCs isolation from ovarian tissue, which these methods could be chosen depends on aim of isolation and accessible equipments and materials in lab. Although isolated OSCs from different methods have various traits and characterizations, which might become from their different nature and origin, however these stem cells are promising source for woman infertility treatment or source of energy for women with a history of repeat IVF failure in near future. This review has brought together and summarized currently used protocols for isolation and propagation of OSCs in vitro.

Evaluation of perceived and actual competency in a family medicine objective structured clinical examination

PubMed Central

Graves, Lisa; Lalla, Leonora; Young, Meredith

2017-01-01

Abstract Objective To examine the relationship between objective assessment of performance and self-rated competence immediately before and after participation in a required summative family medicine clerkship objective structured clinical examination (OSCE). Design Learners rated their competence (on a 7-point Likert scale) before and after an OSCE along 3 dimensions: general, specific, and professional competencies relevant to family medicine. Setting McGill University in Montreal, Que. Participants All 168 third-year clinical clerks completing their mandatory family medicine rotation in 2010 to 2011 were invited to participate. Main outcome measures Self-ratings of competence and objective performance scores were compared, and were examined to determine if OSCEs could be a “corrective” tool for self-rating perceived competence (ie, if the experience of undergoing an assessment might assist learners in recalibrating their understanding of their own performance). Results A total of 140 (83%) of the third-year clinical clerks participated. Participating in an OSCE decreased learners’ ratings of perceived competence (pre-OSCE score = 4.9, post-OSCE score = 4.7; F1,3192 = 4.2; P < .05). Learners’ mean self-rated competence for all categories of behaviour (before and after) showed no relationship to OSCE performance (r < 0.12 and P > .08 for all), nor did ratings of station-relevant competence (before and after) (r < 0.19 and P > .09 for all). Ratings of competence before and after the OSCE were correlated for individual students (r > 0.40 and P < .001 for all). Conclusion After the OSCE, students’ self-ratings of perceived competence had decreased, and these ratings had little relationship to actual performance, regardless of the specificity of the rated competency. Discordance between perceived and actual competence is neither novel nor unique to family medicine. However, this discordance is an important consideration for the development of competency

Neuroprotective effects of oxysophocarpine on neonatal rat primary cultured hippocampal neurons injured by oxygen-glucose deprivation and reperfusion.

PubMed

Zhu, Qing-Luan; Li, Yu-Xiang; Zhou, Ru; Ma, Ning-Tian; Chang, Ren-Yuan; Wang, Teng-Fei; Zhang, Yi; Chen, Xiao-Ping; Hao, Yin-Ju; Jin, Shao-Ju; Ma, Lin; Du, Juan; Sun, Tao; Yu, Jian-Qiang

2014-08-01

Oxysophocarpine (OSC), a quinolizidine alkaloid extracted from leguminous plants of the genus Robinia, is traditionally used for various diseases including neuronal disorders. This study investigated the protective effects of OSC on neonatal rat primary-cultured hippocampal neurons were injured by oxygen-glucose deprivation and reperfusion (OGD/RP). Cultured hippocampal neurons were exposed to OGD for 2 h followed by a 24 h RP. OSC (1, 2, and 5 μmol/L) and nimodipine (Nim) (12 μmol/L) were added to the culture after OGD but before RP. The cultures of the control group were not exposed to OGD/RP. MTT and LDH assay were used to evaluate the protective effects of OSC. The concentration of intracellular-free calcium [Ca(2+)]i and mitochondrial membrane potential (MMP) were determined to evaluate the degree of neuronal damage. Morphologic changes of neurons following OGD/RP were observed with a microscope. The expression of caspase-3 and caspase-12 mRNA was examined by real-time quantitative PCR. The IC50 of OSC was found to be 100 μmol/L. Treatment with OSC (1, 2, and 5 μmol/L) attenuated neuronal damage (p < 0.001), with evidence of increased cell viability (p < 0.001) and decreased cell morphologic impairment. Furthermore, OSC increased MMP (p < 0.001), but it inhibited [Ca(2+)]i (p < 0.001) elevation in a dose-dependent manner at OGD/RP. OSC (5 μmol/L) also decreased the expression of caspase-3 (p < 0.05) and caspase-12 (p < 0.05). The results suggested that OSC has significant neuroprotective effects that can be attributed to inhibiting endoplasmic reticulum (ER) stress-induced apoptosis.

Evaluation of perceived and actual competency in a family medicine objective structured clinical examination.

PubMed

Graves, Lisa; Lalla, Leonora; Young, Meredith

2017-04-01

To examine the relationship between objective assessment of performance and self-rated competence immediately before and after participation in a required summative family medicine clerkship objective structured clinical examination (OSCE). Learners rated their competence (on a 7-point Likert scale) before and after an OSCE along 3 dimensions: general, specific, and professional competencies relevant to family medicine. McGill University in Montreal, Que. All 168 third-year clinical clerks completing their mandatory family medicine rotation in 2010 to 2011 were invited to participate. Self-ratings of competence and objective performance scores were compared, and were examined to determine if OSCEs could be a "corrective" tool for self-rating perceived competence (ie, if the experience of undergoing an assessment might assist learners in recalibrating their understanding of their own performance). A total of 140 (83%) of the third-year clinical clerks participated. Participating in an OSCE decreased learners' ratings of perceived competence (pre-OSCE score = 4.9, post-OSCE score = 4.7; F 1,3192 = 4.2; P  < .05). Learners' mean self-rated competence for all categories of behaviour (before and after) showed no relationship to OSCE performance ( r < 0.12 and P > .08 for all), nor did ratings of station-relevant competence (before and after) ( r < 0.19 and P > .09 for all). Ratings of competence before and after the OSCE were correlated for individual students ( r > 0.40 and P < .001 for all). After the OSCE, students' self-ratings of perceived competence had decreased, and these ratings had little relationship to actual performance, regardless of the specificity of the rated competency. Discordance between perceived and actual competence is neither novel nor unique to family medicine. However, this discordance is an important consideration for the development of competency-based curricula. Copyright© the College of Family Physicians of Canada.

Does Smoking Hamper Oral Self-Care Among Dental Professionals?

PubMed

Ghasemi, Hadi; Khami, Mohammad Reza; Virtanen, Jorma I; Vehkalahti, Miira M

2015-05-01

Smoking may impact oral self-care (OSC). This study aimed to analyze the role of smoking in OSC among Iranian dental health professionals. The cross-sectional data were collected at two annual dental meetings and seven randomly selected dental schools in Iran. A total of 1,459 respondents composed of 967 general dental practitioners (GDPs), 229 dental educators (DE), and 263 senior dental students (DS) anonymously completed a self-administered questionnaire inquiring about smoking status and OSC. Thirty percent of the male and 12% of the female dental health professionals reported smoking tobacco. There was no difference between their professional status. Women reported better OSC than did men, but only 26% of the women and 17% of the men followed the three most important recommendations for OSC. Smoking was associated with infrequent tooth brushing and flossing, irregular use of fluoride containing toothpaste, consumption of sugary snacks and weak adherence to the recommended OSC guidelines. Dental health education should place more emphasis on smoking counseling and cessation among dental health professionals.

Introducing a Model for Optimal Design of Sequential Objective Structured Clinical Examinations

ERIC Educational Resources Information Center

Mortaz Hejri, Sara; Yazdani, Kamran; Labaf, Ali; Norcini, John J.; Jalili, Mohammad

2016-01-01

In a sequential OSCE which has been suggested to reduce testing costs, candidates take a short screening test and who fail the test, are asked to take the full OSCE. In order to introduce an effective and accurate sequential design, we developed a model for designing and evaluating screening OSCEs. Based on two datasets from a 10-station…

Significantly greater expression of ER, PR, and ECAD in advanced-stage low-grade ovarian serous carcinoma as revealed by immunohistochemical analysis.

PubMed

Wong, Kwong-Kwok; Lu, Karen H; Malpica, Anais; Bodurka, Diane C; Shvartsman, Hyun S; Schmandt, Rosemarie E; Thornton, Angela D; Deavers, Michael T; Silva, Elvio G; Gershenson, David M

2007-10-01

A 2-tier system that classifies ovarian serous carcinoma (OSC) as low grade or high grade is gaining acceptance. Women with low-grade OSC generally have higher 5-year survival rates than do women with high-grade OSC. We examined the expression of various markers to further understand the molecular differences between low-grade and high-grade OSCs: the potential therapeutic targets or prognostic markers Her-2/neu, estrogen receptor, and progesterone receptor (PR); the metastasis-associated markers cyclin D1 (BCL1), E-cadherin, matrix metalloproteinase (MMP) 2, and MMP-9; and the cell proliferation-associated markers BCL1, Ki-67 antigen (Ki-67), and p53. For this immunohistochemical analysis, we used paraffin-embedded specimens from 47 patients with advanced-stage low-grade OSC and from 49 patients with advanced-stage high-grade OSC. Our results showed that low-grade tumors expressed significantly higher levels of estrogen receptor, PR, and E-cadherin than did high-grade tumors, suggesting the involvement of gonadal steroid hormones, especially in the pathogenesis of low-grade OSC; the PR positivity was also observed in the stromal component of these low-grade tumors. On the other hand, high-grade tumors trended toward increased expression of MMP-9, BCL1, p53, and Ki-67, and robust MMP-9 positivity was observed in the stromal component of these high-grade tumors. These differences may lead to the development of different therapeutic strategies for women with either the low-grade or the high-grade form of OSC.

Relationships of organizational social capital with the presence of "gossip and slander," "quarrels and conflicts," sick leave, and poor work ability in nursing homes.

PubMed

Kiss, Philippe; De Meester, Marc; Kristensen, Tage S; Braeckman, Lutgart

2014-11-01

This study aimed to explore the associations of organizational social capital (OSC) with the presence of "gossip and slander," the presence of "conflicts and quarrels," sick leave prevalence, and prevalence of poor work ability in frontline working personnel of nursing homes. A total of 239 subjects (81 % participation), working in 11 different nursing homes, took part in a cross-sectional questionnaire study. Following end points were considered, they are as follows: prevalence of "gossip and slander," "conflicts and quarrels," sick leave, and poor work ability. Associations with OSC were explored at individual level (binomial log-linear regression analysis) and on group level (Kendall's tau correlation coefficients). Significant associations were found between OSC and "gossip and slander," sick leave, and poor work ability, both in the individual- and group-level analyses. The associations showed a higher significance level in the group-level analyses, with the strongest association found between mean OSC of the workplace and the prevalence of poor work ability at the workplace (τ = -0.722; p = 0.002). This study demonstrated significant associations of OSC with three end points that are relevant within the framework of well-being at work in nursing homes. The results are suggestive that OSC should be treated as a characteristic of the entire workplace, rather than as an individually experienced characteristic. The strikingly strong association between OSC and prevalence of poor work ability is suggestive for an important role of OSC within the context of maintaining work ability.

Multifunctional oxidosqualene cyclases and cytochrome P450 involved in the biosynthesis of apple fruit triterpenic acids.

PubMed

Andre, Christelle M; Legay, Sylvain; Deleruelle, Amélie; Nieuwenhuizen, Niels; Punter, Matthew; Brendolise, Cyril; Cooney, Janine M; Lateur, Marc; Hausman, Jean-François; Larondelle, Yvan; Laing, William A

2016-09-01

Apple (Malus × domestica) accumulates bioactive ursane-, oleanane-, and lupane-type triterpenes in its fruit cuticle, but their biosynthetic pathway is still poorly understood. We used a homology-based approach to identify and functionally characterize two new oxidosqualene cyclases (MdOSC4 and MdOSC5) and one cytochrome P450 (CYP716A175). The gene expression patterns of these enzymes and of previously described oxidosqualene cyclases were further studied in 20 apple cultivars with contrasting triterpene profiles. MdOSC4 encodes a multifunctional oxidosqualene cyclase producing an oleanane-type triterpene, putatively identified as germanicol, as well as β-amyrin and lupeol, in the proportion 82 : 14 : 4. MdOSC5 cyclizes 2,3-oxidosqualene into lupeol and β-amyrin at a ratio of 95 : 5. CYP716A175 catalyses the C-28 oxidation of α-amyrin, β-amyrin, lupeol and germanicol, producing ursolic acid, oleanolic acid, betulinic acid, and putatively morolic acid. The gene expression of MdOSC1 was linked to the concentrations of ursolic and oleanolic acid, whereas the expression of MdOSC5 was correlated with the concentrations of betulinic acid and its caffeate derivatives. Two new multifuntional triterpene synthases as well as a multifunctional triterpene C-28 oxidase were identified in Malus × domestica. This study also suggests that MdOSC1 and MdOSC5 are key genes in apple fruit triterpene biosynthesis. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

New phases of osmium carbide from evolutionary algorithm and ab initio computations

NASA Astrophysics Data System (ADS)

Fadda, Alessandro; Fadda, Giuseppe

2017-09-01

New crystal phases of osmium carbide are presented in this work. These results were found with the CA code, an evolutionary algorithm (EA) presented in a previous paper which takes full advantage of crystal symmetry by using an ad hoc search space and genetic operators. The new OsC2 and Os2C structures have a lower enthalpy than any known so far. Moreover, the layered pattern of OsC2 serves as a blueprint for building new crystals by adding or removing layers of carbon and/or osmium and generating many other Os  +  C structures like Os2C, OsC, OsC2 and OsC4. These again have a lower enthalpy than all the investigated structures, including those of the present work. The mechanical, vibrational and electronic properties are discussed as well.

Student assessment by objective structured examination in a neurology clerkship

PubMed Central

Adesoye, Taiwo; Smith, Sandy; Blood, Angela; Brorson, James R.

2012-01-01

Objectives: We evaluated the reliability and predictive ability of an objective structured clinical examination (OSCE) in the assessment of medical students at the completion of a neurology clerkship. Methods: We analyzed data from 195 third-year medical students who took the OSCE. For each student, the OSCE consisted of 2 standardized patient encounters. The scores obtained from each encounter were compared. Faculty clinical evaluations of each student for 2 clinical inpatient rotations were also compared. Hierarchical regression analysis was applied to test the ability of the averaged OSCE scores to predict standardized written examination scores and composite clinical scores. Results: Students' OSCE scores from the 2 standardized patient encounters were significantly correlated with each other (r = 0.347, p < 0.001), and the scores for all students were normally distributed. In contrast, students' faculty clinical evaluation scores from 2 different clinical inpatient rotations were uncorrelated, and scores were skewed toward the highest ratings. After accounting for clerkship order, better OSCE scores were predictive of better National Board of Medical Examiners standardized examination scores (R2Δ = 0.131, p < 0.001) and of better faculty clinical scores (R2Δ = 0.078, p < 0.001). Conclusions: Student assessment by an OSCE provides a reliable and predictive objective assessment of clinical performance in a neurology clerkship. PMID:22855865

Efficient Semitransparent Organic Solar Cells with Tunable Color enabled by an Ultralow-Bandgap Nonfullerene Acceptor.

PubMed

Cui, Yong; Yang, Chenyi; Yao, Huifeng; Zhu, Jie; Wang, Yuming; Jia, Guoxiao; Gao, Feng; Hou, Jianhui

2017-11-01

Semitransparent organic solar cells (OSCs) show attractive potential in power-generating windows. However, the development of semitransparent OSCs is lagging behind opaque OSCs. Here, an ultralow-bandgap nonfullerene acceptor, "IEICO-4Cl", is designed and synthesized, whose absorption spectrum is mainly located in the near-infrared region. When IEICO-4Cl is blended with different polymer donors (J52, PBDB-T, and PTB7-Th), the colors of the blend films can be tuned from purple to blue to cyan, respectively. Traditional OSCs with a nontransparent Al electrode fabricated by J52:IEICO-4Cl, PBDB-T:IEICO-4Cl, and PTB7-Th:IEICO-4Cl yield power conversion efficiencies (PCE) of 9.65 ± 0.33%, 9.43 ± 0.13%, and 10.0 ± 0.2%, respectively. By using 15 nm Au as the electrode, semitransparent OSCs based on these three blends also show PCEs of 6.37%, 6.24%, and 6.97% with high average visible transmittance (AVT) of 35.1%, 35.7%, and 33.5%, respectively. Furthermore, via changing the thickness of Au in the OSCs, the relationship between the transmittance and efficiency is studied in detail, and an impressive PCE of 8.38% with an AVT of 25.7% is obtained, which is an outstanding value in the semitransparent OSCs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Prevalence and Incidence of Traumatic Experiences Among Orphans in Institutional and Family-Based Settings in 5 Low- and Middle-Income Countries: A Longitudinal Study.

PubMed

Gray, Christine L; Pence, Brian W; Ostermann, Jan; Whetten, Rachel A; O'Donnell, Karen; Thielman, Nathan M; Whetten, Kathryn

2015-08-25

Policy makers struggling to protect the 153 million orphaned and separated children (OSC) worldwide need evidence-based research on the burden of potentially traumatic events (PTEs) and the relative risk of PTEs across different types of care settings. The Positive Outcomes for Orphans study used a 2-stage, cluster-randomized sampling design to identify 1,357 institution-dwelling and 1,480 family-dwelling orphaned and separated children in 5 low- and middle-income countries (LMICs) in sub-Saharan Africa and Asia. We used the Life Events Checklist developed by the National Center for Posttraumatic Stress Disorder to examine self-reported PTEs among 2,235 OSC ages 10-13 at baseline. We estimated prevalence and incidence during 36-months of follow-up and compared the risk of PTEs across care settings. Data collection began between May 2006 and February 2008, depending on the site. Lifetime prevalence by age 13 of any PTE, excluding loss of a parent, was 91.0% (95% confidence interval (CI) = 85.6, 94.5) in institution-dwelling OSC and 92.4% (95% CI = 90.3, 94.0) in family-dwelling OSC; annual incidence of any PTE was lower in institution-dwelling (23.6% [95% CI = 19.4, 28.7]) than family-dwelling OSC (30.0% [95% CI = 28.1, 32.2]). More than half of children in institutions (50.3% [95% CI = 42.5, 58.0]) and in family-based care (54.0% [95% CI = 50.2, 57.7]) had experienced physical or sexual abuse by age 13. Annual incidence of physical or sexual abuse was lower in institution-dwelling (12.9% [95% CI = 9.6, 17.3]) than family-dwelling OSC (19.4% [95% CI = 17.7, 21.3]), indicating statistically lower risk in institution-dwelling OSC (risk difference = 6.5% [95% CI = 1.4, 11.7]). Prevalence and incidence of PTEs were high among OSC, but contrary to common assumptions, OSC living in institutions did not report more PTEs or more abuse than OSC living with families. Current efforts to reduce the number of institution-dwelling OSC may

Prevalence and Incidence of Traumatic Experiences Among Orphans in Institutional and Family-Based Settings in 5 Low- and Middle-Income Countries: A Longitudinal Study

PubMed Central

Pence, Brian W; Ostermann, Jan; Whetten, Rachel A; O’Donnell, Karen; Thielman, Nathan M; Whetten, Kathryn

2015-01-01

Background: Policy makers struggling to protect the 153 million orphaned and separated children (OSC) worldwide need evidence-based research on the burden of potentially traumatic events (PTEs) and the relative risk of PTEs across different types of care settings. Methods: The Positive Outcomes for Orphans study used a 2-stage, cluster-randomized sampling design to identify 1,357 institution-dwelling and 1,480 family-dwelling orphaned and separated children in 5 low- and middle-income countries (LMICs) in sub-Saharan Africa and Asia. We used the Life Events Checklist developed by the National Center for Posttraumatic Stress Disorder to examine self-reported PTEs among 2,235 OSC ages 10–13 at baseline. We estimated prevalence and incidence during 36-months of follow-up and compared the risk of PTEs across care settings. Data collection began between May 2006 and February 2008, depending on the site. Results: Lifetime prevalence by age 13 of any PTE, excluding loss of a parent, was 91.0% (95% confidence interval (CI) = 85.6, 94.5) in institution-dwelling OSC and 92.4% (95% CI = 90.3, 94.0) in family-dwelling OSC; annual incidence of any PTE was lower in institution-dwelling (23.6% [95% CI = 19.4, 28.7]) than family-dwelling OSC (30.0% [95% CI = 28.1, 32.2]). More than half of children in institutions (50.3% [95% CI = 42.5, 58.0]) and in family-based care (54.0% [95% CI = 50.2, 57.7]) had experienced physical or sexual abuse by age 13. Annual incidence of physical or sexual abuse was lower in institution-dwelling (12.9% [95% CI = 9.6, 17.3]) than family-dwelling OSC (19.4% [95% CI = 17.7, 21.3]), indicating statistically lower risk in institution-dwelling OSC (risk difference = 6.5% [95% CI = 1.4, 11.7]). Conclusion: Prevalence and incidence of PTEs were high among OSC, but contrary to common assumptions, OSC living in institutions did not report more PTEs or more abuse than OSC living with families. Current efforts to reduce

Introduction of craniomaxillofacial surgery as a component of medical student training in general surgery.

PubMed

Schuebel, Florian; Höfer, Sebastian H; Rüsseler, Miriam; Walcher, Felix; Sader, Robert; Landes, Constantin

2014-11-01

This study provides an overview of the objective structured clinical examination (OSCE) in concept, determination of task difficulty, execution, and evaluation by students and examiners. During a 4-semester study period, 507 medical students completed a practical skills training (PST) course and subsequently participated in a 16-station OSCE, which contained 2 craniomaxillofacial surgical (CMS) stations covering the following key tasks: craniofacial examination and facial trauma fracture management. The students were rated using dedicated checklists. The students subjectively evaluated the PST and the OSCE using anonymous evaluation forms. Students rated the PST and OSCE as "very positive." The CMS OSCE stations were rated as having good task difficulty (74.05 ± 1.78% average task fulfilment for the examination and 74.45 ± 3.40% for the management station). With no changes to the examination station, no significant improvement of performance occurred over the entire investigation period (P = .787). In contrast, students improved slightly at the management station (P = .308). The CMS stations showed high selectivity and were representative in the overall context of the OSCE; improvement of selectivity increased from 0.259 ± 0.088 to 0.465 ± 0.109. CMS was successfully implemented in the general surgical training for medical students, with an initial PST and a final OSCE concordant with the literature. The CMS implementation effectively trained and fairly evaluated clinical skills. Although an OSCE consumes time and resources, this addition proved feasible and valuable, even with large numbers of students, and students expressed a high level of satisfaction with the training. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Regulation of Injury-Induced Ovarian Regeneration by Activation of Oogonial Stem Cells.

PubMed

Erler, Piril; Sweeney, Alexandra; Monaghan, James R

2017-01-01

Some animals have the ability to generate large numbers of oocytes throughout life. This raises the question whether persistent adult germline stem cell populations drive continuous oogenesis and whether they are capable of mounting a regenerative response after injury. Here we demonstrate the presence of adult oogonial stem cells (OSCs) in the adult axolotl salamander ovary and show that ovarian injury induces OSC activation and functional regeneration of the ovaries to reproductive capability. Cells that have morphological similarities to germ cells were identified in the developing and adult ovaries via histological analysis. Genes involved in germ cell maintenance including Vasa, Oct4, Sox2, Nanog, Bmp15, Piwil1, Piwil2, Dazl, and Lhx8 were expressed in the presumptive OSCs. Colocalization of Vasa protein with H3 mitotic marker showed that both oogonial and spermatogonial adult stem cells were mitotically active. Providing evidence of stemness and viability of adult OSCs, enhanced green fluorescent protein (EGFP) adult OSCs grafted into white juvenile host gonads gave rise to EGFP OSCs, and oocytes. Last, the axolotl ovaries completely regenerated after partial ovariectomy injury. During regeneration, OSC activation resulted in rapid differentiation into new oocytes, which was demonstrated by Vasa + /BrdU + coexpression. Furthermore, follicle cell proliferation promoted follicle maturation during ovarian regeneration. Overall, these results show that adult oogenesis occurs via proliferation of endogenous OSCs in a tetrapod and mediates ovarian regeneration. This study lays the foundations to elucidate mechanisms of ovarian regeneration that will assist regenerative medicine in treating premature ovarian failure and reduced fertility. Stem Cells 2017;35:236-247. © 2016 AlphaMed Press.

Non-fullerene acceptors for organic solar cells

NASA Astrophysics Data System (ADS)

Yan, Cenqi; Barlow, Stephen; Wang, Zhaohui; Yan, He; Jen, Alex K.-Y.; Marder, Seth R.; Zhan, Xiaowei

2018-03-01

Non-fullerene acceptors (NFAs) are currently a major focus of research in the development of bulk-heterojunction organic solar cells (OSCs). In contrast to the widely used fullerene acceptors (FAs), the optical properties and electronic energy levels of NFAs can be readily tuned. NFA-based OSCs can also achieve greater thermal stability and photochemical stability, as well as longer device lifetimes, than their FA-based counterparts. Historically, the performance of NFA OSCs has lagged behind that of fullerene devices. However, recent developments have led to a rapid increase in power conversion efficiencies for NFA OSCs, with values now exceeding 13%, demonstrating the viability of using NFAs to replace FAs in next-generation high-performance OSCs. This Review discusses the important work that has led to this remarkable progress, focusing on the two most promising NFA classes to date: rylene diimide-based materials and materials based on fused aromatic cores with strong electron-accepting end groups. The key structure-property relationships, donor-acceptor matching criteria and aspects of device physics are discussed. Finally, we consider the remaining challenges and promising future directions for the NFA OSCs field.

Electric Field Tuning Molecular Packing and Electrical Properties of Solution-Shearing Coated Organic Semiconducting Thin Films

DOE PAGES

Molina-Lopez, Francisco; Yan, Hongping; Gu, Xiaodan; ...

2017-01-17

Recent improvements in solution-coated organic semiconductors (OSCs) evidence their high potential for cost-efficient organic electronics and sensors. Molecular packing structure determines the charge transport property of molecular solids. However, it remains challenging to control the molecular packing structure for a given OSC. Here, the application of alternating electric fields is reported to fine-tune the crystal packing of OSC solution-shearing coated at ambient conditions. First, a theoretical model based on dielectrophoresis is developed to guide the selection of the optimal conditions (frequency and amplitude) of the electric field applied through the solution-shearing blade during coating of OSC thin films. Next, electricmore » field-induced polymorphism is demonstrated for OSCs with both herringbone and 2D brick-wall packing motifs in 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene and 6,13-bis(triisopropylsilylethynyl) pentacene, respectively. Favorable molecular packing can be accessible in some cases, resulting in higher charge carrier mobilities. In conclusion, this work provides a new approach to tune the properties of solution-coated OSCs in functional devices for high-performance printed electronics.« less

Qualitative analysis of student beliefs and attitudes after an objective structured clinical evaluation: implications for affective domain learning in undergraduate nursing education.

PubMed

Cazzell, Mary; Rodriguez, Amber

2011-12-01

This qualitative study explored the feelings, beliefs, and attitudes of senior-level undergraduate pediatric nursing students upon completion of a medication administration Objective Structured Clinical Evaluation (OSCE). The affective domain is the most neglected domain in higher education, although it is deemed the "gateway to learning." Quantitative assessments of clinical skills performed during OSCEs usually address two of the three domains of learning: cognitive (knowledge) and psychomotor skills. Twenty students volunteered to participate in focus groups (10 per group) and were asked three questions relevant to their feelings, beliefs, and attitudes about their OSCE experiences. Students integrated the attitude of safety first into future practice but felt that anxiety, loss of control, reaction under pressure, and no feedback affected their ability to connect the OSCE performance with future clinical practice. The findings affect future affective domain considerations in the development, modification, and assessment of OSCEs across the undergraduate nursing curriculum.

Fully Printable Organic and Perovskite Solar Cells with Transfer-Printed Flexible Electrodes.

PubMed

Li, Xianqiang; Tang, Xiaohong; Ye, Tao; Wu, Dan; Wang, Hong; Wang, Xizu

2017-06-07

The perovskite solar cells (PSCs) and organic solar cells (OSCs) with high performance were fabricated with transfer-printed top metal electrodes. We have demonstrated that PSCs and OSCs with the top Au electrodes fabricated by using the transfer printing method have comparable or better performance than the devices with the top Au electrodes fabricated by using the conventional thermal evaporation method. The highest PCE of the PSCs and OSCs with the top electrodes fabricated using the transfer printing method achieved 13.72% and 2.35%, respectively. It has been investigated that fewer defects between the organic thin films and Au electrodes exist by using the transfer printing method which improved the device stability. After storing the PSCs and OSCs with the transfer-printed electrodes in a nitrogen environment for 97 and 103 days without encapsulation, the PSCs and OSCs still retained 71% and 91% of their original PCEs, respectively.

Situational awareness within objective structured clinical examination stations in undergraduate medical training - a literature search.

PubMed

Fischer, Markus A; Kennedy, Kieran M; Durning, Steven; Schijven, Marlies P; Ker, Jean; O'Connor, Paul; Doherty, Eva; Kropmans, Thomas J B

2017-12-21

Medical students may not be able to identify the essential elements of situational awareness (SA) necessary for clinical reasoning. Recent studies suggest that students have little insight into cognitive processing and SA in clinical scenarios. Objective Structured Clinical Examinations (OSCEs) could be used to assess certain elements of situational awareness. The purpose of this paper is to review the literature with a view to identifying whether levels of SA based on Endsley's model can be assessed utilising OSCEs during undergraduate medical training. A systematic search was performed pertaining to SA and OSCEs, to identify studies published between January 1975 (first paper describing an OSCE) and February 2017, in peer reviewed international journals published in English. PUBMED, EMBASE, PsycINFO Ovid and SCOPUS were searched for papers that described the assessment of SA using OSCEs among undergraduate medical students. Key search terms included "objective structured clinical examination", "objective structured clinical assessment" or "OSCE" and "non-technical skills", "sense-making", "clinical reasoning", "perception", "comprehension", "projection", "situation awareness", "situational awareness" and "situation assessment". Boolean operators (AND, OR) were used as conjunctions to narrow the search strategy, resulting in the limitation of papers relevant to the research interest. Areas of interest were elements of SA that can be assessed by these examinations. The initial search of the literature retrieved 1127 publications. Upon removal of duplicates and papers relating to nursing, paramedical disciplines, pharmacy and veterinary education by title, abstract or full text, 11 articles were eligible for inclusion as related to the assessment of elements of SA in undergraduate medical students. Review of the literature suggests that whole-task OSCEs enable the evaluation of SA associated with clinical reasoning skills. If they address the levels of SA, these

Bulk-Heterojunction Organic Solar Cells: Five Core Technologies for Their Commercialization.

PubMed

Kang, Hongkyu; Kim, Geunjin; Kim, Junghwan; Kwon, Sooncheol; Kim, Heejoo; Lee, Kwanghee

2016-09-01

The past two decades of vigorous interdisciplinary approaches has seen tremendous breakthroughs in both scientific and technological developments of bulk-heterojunction organic solar cells (OSCs) based on nanocomposites of π-conjugated organic semiconductors. Because of their unique functionalities, the OSC field is expected to enable innovative photovoltaic applications that can be difficult to achieve using traditional inorganic solar cells: OSCs are printable, portable, wearable, disposable, biocompatible, and attachable to curved surfaces. The ultimate objective of this field is to develop cost-effective, stable, and high-performance photovoltaic modules fabricated on large-area flexible plastic substrates via high-volume/throughput roll-to-roll printing processing and thus achieve the practical implementation of OSCs. Recently, intensive research efforts into the development of organic materials, processing techniques, interface engineering, and device architectures have led to a remarkable improvement in power conversion efficiencies, exceeding 11%, which has finally brought OSCs close to commercialization. Current research interests are expanding from academic to industrial viewpoints to improve device stability and compatibility with large-scale printing processes, which must be addressed to realize viable applications. Here, both academic and industrial issues are reviewed by highlighting historically monumental research results and recent state-of-the-art progress in OSCs. Moreover, perspectives on five core technologies that affect the realization of the practical use of OSCs are presented, including device efficiency, device stability, flexible and transparent electrodes, module designs, and printing techniques. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of current undergraduate anesthesia course in a Saudi University.

PubMed

Shams, Tarek; El-Masry, Ragaa; Al Wadani, Hamed; Amr, Mostafa

2013-04-01

The assessment of the anesthesia course in our university comprises Objective Structured Clinical Examinations (OSCEs), in conjunction with portfolio and multiple-choice questions (MCQ). The objective of this study was to evaluate the outcome of different forms of anesthesia course assessment among 5(th) year medical students in our university, as well as study the influence of gender on student performance in anesthesia. We examined the performance of 154, 5(th) year medical students through OSCE, portfolios, and MCQ. The score ranges in the portfolio, OSCE, and MCQs were 16-24, 4.2-28.9, and 15.5-44.5, respectively. There was highly significant difference in scores in relation to gender in all assessments other than the written one (P=0.000 for Portfolio, OSCE, and Total exam, whereas P=0.164 for written exam). In the generated linear regression model, OSCE alone could predict 86.4% of the total mark if used alone. In addition, if the score of the written examination is added, OSCE will drop to 57.2% and the written exam will be 56.8% of the total mark. This study demonstrates that different clinical methods used to assess medical students during their anesthesia course were consistent and integrated. The performance of female was superior to male in OSCE and portfolio. This information is the basis for improving educational and assessment standards in anesthesiology and for introducing a platform for developing modern learning media in countries with dearth of anesthesia personnel.

Low-Temperature Preparation of Tungsten Oxide Anode Buffer Layer via Ultrasonic Spray Pyrolysis Method for Large-Area Organic Solar Cells.

PubMed

Ji, Ran; Zheng, Ding; Zhou, Chang; Cheng, Jiang; Yu, Junsheng; Li, Lu

2017-07-18

Tungsten oxide (WO₃) is prepared by a low-temperature ultrasonic spray pyrolysis method in air atmosphere, and it is used as an anode buffer layer (ABL) for organic solar cells (OSCs). The properties of the WO₃ transition metal oxide material as well as the mechanism of ultrasonic spray pyrolysis processes are investigated. The results show that the ultrasonic spray pyrolysized WO₃ ABL exhibits low roughness, matched energy level, and high conductivity, which results in high charge transport efficiency and suppressive recombination in OSCs. As a result, compared to the OSCs based on vacuum thermal evaporated WO₃, a higher power conversion efficiency of 3.63% is reached with low-temperature ultrasonic spray pyrolysized WO₃ ABL. Furthermore, the mostly spray-coated OSCs with large area was fabricated, which has a power conversion efficiency of ~1%. This work significantly enhances our understanding of the preparation and application of low temperature-processed WO₃, and highlights the potential of large area, all spray coated OSCs for sustainable commercial fabrication.

Evaluation of the Veterans Health Administration's Specialty Care Transformational Initiatives to Promote Patient-Centered Delivery of Specialty Care: A Mixed-Methods Approach.

PubMed

Williams, Katherine M; Kirsh, Susan; Aron, David; Au, David; Helfrich, Christian; Lambert-Kerzner, Anne; Lowery, Julie; Battaglia, Catherine; Graham, Glenn D; Doukas, Michael; Jain, Rajiv; Ho, P Michael

2017-07-01

Veteran's Affairs Office of Specialty Care (OSC) launched four national initiatives (Electronic-Consults [e-Consults], Specialty Care Access Networks-Extension for Community Healthcare Outcomes [SCAN-ECHO], Mini-Residencies, and Specialty Care Neighborhood) to improve specialty care delivery and funded a center to evaluate the initiatives. The evaluation, guided by two implementation frameworks, provides formative (administrator/provider interviews and surveys) and summative data (quantitative data on patterns of use) about the initiatives to OSC. Evaluation of initiative implementation is assessed through CFIR (Consolidated Framework for Implementation Research)-grounded qualitative interviews to identify barriers/facilitators. Depending on high or low implementation, factors such as receiving workload credit, protected time, existing workflow/systems compatibility, leadership engagement, and access to information/resources were considered implementation barriers or facilitators. Findings were shared with OSC and used to further refine implementation at additional sites. Evaluation of other initiatives is ongoing. The mixed-methods approach has provided timely information to OSC about initiative effect and impacted OSC policies on implementation at additional sites.

Interplay between efficiency and device architecture for small molecule organic solar cells.

PubMed

Williams, Graeme; Sutty, Sibi; Aziz, Hany

2014-06-21

Small molecule organic solar cells (OSCs) have experienced a resurgence of interest over their polymer solar cell counterparts, owing to their improved batch-to-batch (thus, cell-to-cell) reliability. In this systematic study on OSC device architecture, we investigate five different small molecule OSC structures, including the simple planar heterojunction (PHJ) and bulk heterojunction (BHJ), as well as several planar-mixed structures. The different OSC structures are studied over a wide range of donor:acceptor mixing concentrations to gain a comprehensive understanding of their charge transport behavior. Transient photocurrent decay measurements provide crucial information regarding the interplay between charge sweep-out and charge recombination, and ultimately hint toward space charge effects in planar-mixed structures. Results show that the BHJ/acceptor architecture, comprising a BHJ layer with high C60 acceptor content, generates OSCs with the highest performance by balancing charge generation with charge collection. The performance of other device architectures is largely limited by hole transport, with associated hole accumulation and space charge effects.

Flipping the Objective Structured Clinical Examination: A Teaching Innovation in Graduate Nursing Education.

PubMed

Day, Cristi; Barker, Connie; Bell, Eva; Sefcik, Elizabeth; Flournoy, Deborah

Objective evaluation of distance-based family nurse practitioner (FNP) students can be challenging. One FNP program piloted a teaching innovation, the video-enhanced objective structured clinical examination (VE-OSCE) or "flip" of the traditional face-to-face OSCE, to assess student clinical performance in a controlled online environment using a teleconferencing platform. This project sought to assess the VE-OSCE design, implementation, and ability to identify FNP student learning needs.

Implementing the objective structured clinical examination in a geriatrics fellowship program-a 3-year experience.

PubMed

Avelino-Silva, Thiago J; Gil, Luiz A; Suemoto, Claudia K; Kikuchi, Elina L; Lin, Sumika M; Farias, Luciana L; Jacob-Filho, Wilson

2012-07-01

The Objective Structured Clinical Examination (OSCE) appears to be an effective alternative for assessing not only medical knowledge, but also clinical skills, including effective communication and physical examination skills. The purpose of the current study was to implement an OSCE model in a geriatrics fellowship program and to compare the instrument with traditional essay examination. Seventy first- and second-year geriatric fellows were initially submitted to a traditional essay examination and scored from 0 to 10 by a faculty member. The same fellows subsequently underwent an OSCE with eight 10-minute stations covering a wide range of essential aspects of geriatric knowledge. Each OSCE station had an examiner responsible for its evaluation according to a predefined checklist. Checklist items were classified for analysis purposes as clinical knowledge items (CKI) and communication skills items (CSI); fellow responses were scored from 0 to 10.Although essay examinations took from 30 to 45 minutes to complete, 180-200 minutes were required to evaluate fellows using the proposed OSCE method. Fellows scored an average of 6.2 ± 1.2 on the traditional essay examination and 6.6 ± 1.0 on the OSCE (P < .001). Subanalyses of OSCE scores indicated that average performance on CKI was lower than the average on CSI (6.4 ± 1.1 vs. 8.4 ± 1.1; P < .001). Fellow performance on the essay examination was similar to their performance on CKI (P = .13). Second-year fellows performed better than first-year fellows on the essay examination (P < .001) and CKI (P = .05), but not on CSI (P = .25).The OSCE was successfully implemented as an educational strategy during a geriatrics fellowship program. Combining different testing modalities may provide the best assessment of competence for various domains of knowledge, skills, and behavior. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

A nanoscale study of charge extraction in organic solar cells: the impact of interfacial molecular configurations.

PubMed

Tang, Fu-Ching; Wu, Fu-Chiao; Yen, Chia-Te; Chang, Jay; Chou, Wei-Yang; Gilbert Chang, Shih-Hui; Cheng, Horng-Long

2015-01-07

In the optimization of organic solar cells (OSCs), a key problem lies in the maximization of charge carriers from the active layer to the electrodes. Hence, this study focused on the interfacial molecular configurations in efficient OSC charge extraction by theoretical investigations and experiments, including small molecule-based bilayer-heterojunction (sm-BLHJ) and polymer-based bulk-heterojunction (p-BHJ) OSCs. We first examined a well-defined sm-BLHJ model system of OSC composed of p-type pentacene, an n-type perylene derivative, and a nanogroove-structured poly(3,4-ethylenedioxythiophene) (NS-PEDOT) hole extraction layer. The OSC with NS-PEDOT shows a 230% increment in the short circuit current density compared with that of the conventional planar PEDOT layer. Our theoretical calculations indicated that small variations in the microscopic intermolecular interaction among these interfacial configurations could induce significant differences in charge extraction efficiency. Experimentally, different interfacial configurations were generated between the photo-active layer and the nanostructured charge extraction layer with periodic nanogroove structures. In addition to pentacene, poly(3-hexylthiophene), the most commonly used electron-donor material system in p-BHJ OSCs was also explored in terms of its possible use as a photo-active layer. Local conductive atomic force microscopy was used to measure the nanoscale charge extraction efficiency at different locations within the nanogroove, thus highlighting the importance of interfacial molecular configurations in efficient charge extraction. This study enriches understanding regarding the optimization of the photovoltaic properties of several types of OSCs by conducting appropriate interfacial engineering based on organic/polymer molecular orientations. The ultimate power conversion efficiency beyond at least 15% is highly expected when the best state-of-the-art p-BHJ OSCs are combined with present arguments.

A Descriptive Survey of Anesthesiology Residency Simulation Programs: How Are Programs Preparing Residents for the New American Board of Anesthesiology APPLIED Certification Examination?

PubMed

Isaak, Robert S; Chen, Fei; Arora, Harendra; Martinelli, Susan M; Zvara, David A; Stiegler, Marjorie P

2017-09-01

Anesthesiology residency programs may need new simulation-based programs to prepare residents for the new Objective Structured Clinical Examination (OSCE) component of the American Board of Anesthesiology (ABA) Primary Certification process. The design of such programs may require significant resources, including faculty time, expertise, and funding, as are currently needed for structured oral examination (SOE) preparation. This survey analyzed the current state of US-based anesthesiology residency programs regarding simulation-based educational programming for SOE and OSCE preparation. An online survey was distributed to every anesthesiology residency program director in the United States. The survey included 15 to 46 questions, depending on each respondent's answers. The survey queried current practices and future plans regarding resident preparation specifically for the ABA APPLIED examination, with emphasis on the OSCE. Descriptive statistics were summarized. χ and Fisher exact tests were used to test the differences in proportions across groups. Spearman rank correlation was used to examine the association between ordinal variables. The responding 66 programs (49%) were a representative sample of all anesthesiology residencies (N = 136) in terms of geographical location (χ P = .58). There was a low response rate from small programs that have 12 or fewer clinical anesthesia residents. Ninety-one percent (95% confidence interval [CI], 84%-95%) of responders agreed that it is the responsibility of the program to specifically prepare residents for primary certification, and most agreed that it is important to practice SOEs (94%; 95% CI, 88%-97%) and OSCEs (89%; 95% CI, 83%-94%). While 100% of respondents reported providing mock SOEs, only 31% (95% CI, 24%-40%) of respondents provided mock OSCE experiences. Of those without an OSCE program, 75% (95% CI, 64%-83%) reported plans to start one. The most common reasons for not having an OSCE program already in place

Factores que Influencian la Adquisición de Infecciones de Transmisión Sexual y VIH en Mujeres Jóvenes Chilenas que Participaron en la Intervención Online I-STIPI

PubMed Central

Villegas, Natalia; Cianelli, Rosina; Santisteban, Daniel; Lara, Loreto; Vargas, Jessica

2017-01-01

Resumen El objetivo de este estudio descriptivo de corte transversal fue investigar los siguientes factores asociados a la prevención de las infecciones de transmisión sexual (ITS) y el virus de la inmunodeficiencia humana (VIH): (a) conocimientos, (b) actitudes, (c) autoeficacia, (d) vulnerabilidad, (e) conductas de riesgo, (f) conductas de prevención, y (g) uso de internet en mujeres chilenas entre 18 y 24 años. Se utilizó un cuestionario estructurado disponible en un sitio web seguro para la recolección de datos que incluyó preguntas relacionadas con la prevención de ITS/VIH. Los resultados del estudio indicaron que las mujeres jóvenes están en riesgo de adquirir ITS/VIH y tienen necesidades especiales para la prevención. La familiaridad y frecuencia del uso de internet en esta población puede ser utilizado para la prevención de ITS/VIH. PMID:27257190

Associations of medical student empathy with clinical competence.

PubMed

Casas, Rachel S; Xuan, Ziming; Jackson, Angela H; Stanfield, Lorraine E; Harvey, Nanette C; Chen, Daniel C

2017-04-01

Empathy is a crucial skill for medical students that can be difficult to evaluate. We examined if self-reported empathy in medical students was associated with clinical competence. This study combined cross-sectional data from four consecutive years of medical students (N=590) from the Boston University School of Medicine. We used regression analysis to evaluate if self-reported empathy (Jefferson Scale of Physician Empathy (JSPE)) predicted scores in clinical clerkships, United States Medical Licensing Examinations, and OBJECTIVE: Structured Clinical Examinations (OSCEs). We separately analyzed overall and OSCE communication scores based on interpersonal skills reported by standardized patients. We controlled for age, gender, debt, and specialty affinity. JSPE scores of medical students were positively associated with OSCE communication scores, and remained significant when controlling for demographics. We found that JSPE score was also predictive of overall OSCE scores, but this relationship was confounded by gender and age. JSPE scores were associated with performance in the Pediatrics clerkship, but not other clerkships or standardized tests. JSPE scores were positively associated with OSCE communication scores in medical students. This study supports that self-reported empathy may predict OSCE performance, but further research is needed to examine differences by gender and age. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Neurology objective structured clinical examination reliability using generalizability theory

PubMed Central

Park, Yoon Soo; Lukas, Rimas V.; Brorson, James R.

2015-01-01

Objectives: This study examines factors affecting reliability, or consistency of assessment scores, from an objective structured clinical examination (OSCE) in neurology through generalizability theory (G theory). Methods: Data include assessments from a multistation OSCE taken by 194 medical students at the completion of a neurology clerkship. Facets evaluated in this study include cases, domains, and items. Domains refer to areas of skill (or constructs) that the OSCE measures. G theory is used to estimate variance components associated with each facet, derive reliability, and project the number of cases required to obtain a reliable (consistent, precise) score. Results: Reliability using G theory is moderate (Φ coefficient = 0.61, G coefficient = 0.64). Performance is similar across cases but differs by the particular domain, such that the majority of variance is attributed to the domain. Projections in reliability estimates reveal that students need to participate in 3 OSCE cases in order to increase reliability beyond the 0.70 threshold. Conclusions: This novel use of G theory in evaluating an OSCE in neurology provides meaningful measurement characteristics of the assessment. Differing from prior work in other medical specialties, the cases students were randomly assigned did not influence their OSCE score; rather, scores varied in expected fashion by domain assessed. PMID:26432851

The Oxidosqualene Cyclase from the Oomycete Saprolegnia parasitica Synthesizes Lanosterol as a Single Product

PubMed Central

Dahlin, Paul; Srivastava, Vaibhav; Bulone, Vincent; McKee, Lauren S.

2016-01-01

The first committed step of sterol biosynthesis is the cyclisation of 2,3-oxidosqualene to form either lanosterol (LA) or cycloartenol (CA). This is catalyzed by an oxidosqualene cyclase (OSC). LA and CA are subsequently converted into various sterols by a series of enzyme reactions. The specificity of the OSC therefore determines the final composition of the end sterols of an organism. Despite the functional importance of OSCs, the determinants of their specificity are not well understood. In sterol-synthesizing oomycetes, recent bioinformatics, and metabolite analysis suggest that LA is produced. However, this catalytic activity has never been experimentally demonstrated. Here, we show that the OSC of the oomycete Saprolegnia parasitica, a severe pathogen of salmonid fish, has an uncommon sequence in a conserved motif important for specificity. We present phylogenetic analysis revealing that this sequence is common to sterol-synthesizing oomycetes, as well as some plants, and hypothesize as to the evolutionary origin of some microbial sequences. We also demonstrate for the first time that a recombinant form of the OSC from S. parasitica produces LA exclusively. Our data pave the way for a detailed structural characterization of the protein and the possible development of specific inhibitors of oomycete OSCs for disease control in aquaculture. PMID:27881978

Neurology objective structured clinical examination reliability using generalizability theory.

PubMed

Blood, Angela D; Park, Yoon Soo; Lukas, Rimas V; Brorson, James R

2015-11-03

This study examines factors affecting reliability, or consistency of assessment scores, from an objective structured clinical examination (OSCE) in neurology through generalizability theory (G theory). Data include assessments from a multistation OSCE taken by 194 medical students at the completion of a neurology clerkship. Facets evaluated in this study include cases, domains, and items. Domains refer to areas of skill (or constructs) that the OSCE measures. G theory is used to estimate variance components associated with each facet, derive reliability, and project the number of cases required to obtain a reliable (consistent, precise) score. Reliability using G theory is moderate (Φ coefficient = 0.61, G coefficient = 0.64). Performance is similar across cases but differs by the particular domain, such that the majority of variance is attributed to the domain. Projections in reliability estimates reveal that students need to participate in 3 OSCE cases in order to increase reliability beyond the 0.70 threshold. This novel use of G theory in evaluating an OSCE in neurology provides meaningful measurement characteristics of the assessment. Differing from prior work in other medical specialties, the cases students were randomly assigned did not influence their OSCE score; rather, scores varied in expected fashion by domain assessed. © 2015 American Academy of Neurology.

Improved interface control for high-performance graphene-based organic solar cells

NASA Astrophysics Data System (ADS)

Jung, Seungon; Lee, Junghyun; Choi, Yunseong; Myeon Lee, Sang; Yang, Changduk; Park, Hyesung

2017-12-01

The demand for high-efficiency flexible optoelectronic devices is ever-increasing because next-generation electronic devices that comprise portable or wearable electronic systems are set to play an important role. Graphene has received extensive attention as it is considered to be a promising candidate material for transparent flexible electrode platforms owing to its outstanding electrical, optical, and physical properties. Despite these properties, the inert and hydrophobic nature of graphene surfaces renders it difficult to use in optoelectronic devices. In particular, commonly used charge transporting layer (CTL) materials for organic solar cells (OSCs) cannot uniformly coat a graphene surface, which leads to such devices failing. Herein, this paper proposes an approach that will enable CTL materials to completely cover a graphene electrode; this is done with the assistance of commonly accessible polar solvents. These are successfully applied to various configurations of OSCs, with power conversion efficiencies of 8.17% for graphene electrode-based c-OSCs (OSCs with conventional structures), 8.38% for i-OSCs (OSCs with inverted structures), and 7.53% for flexible solar cells. The proposed approach is expected to bring about significant advances for efficiency enhancements in graphene-based optoelectronic devices, and it is expected that it will open up new possibilities for flexible optoelectronic systems.

The Oxidosqualene Cyclase from the Oomycete Saprolegnia parasitica Synthesizes Lanosterol as a Single Product.

PubMed

Dahlin, Paul; Srivastava, Vaibhav; Bulone, Vincent; McKee, Lauren S

2016-01-01

The first committed step of sterol biosynthesis is the cyclisation of 2,3-oxidosqualene to form either lanosterol (LA) or cycloartenol (CA). This is catalyzed by an oxidosqualene cyclase (OSC). LA and CA are subsequently converted into various sterols by a series of enzyme reactions. The specificity of the OSC therefore determines the final composition of the end sterols of an organism. Despite the functional importance of OSCs, the determinants of their specificity are not well understood. In sterol-synthesizing oomycetes, recent bioinformatics, and metabolite analysis suggest that LA is produced. However, this catalytic activity has never been experimentally demonstrated. Here, we show that the OSC of the oomycete Saprolegnia parasitica , a severe pathogen of salmonid fish, has an uncommon sequence in a conserved motif important for specificity. We present phylogenetic analysis revealing that this sequence is common to sterol-synthesizing oomycetes, as well as some plants, and hypothesize as to the evolutionary origin of some microbial sequences. We also demonstrate for the first time that a recombinant form of the OSC from S. parasitica produces LA exclusively. Our data pave the way for a detailed structural characterization of the protein and the possible development of specific inhibitors of oomycete OSCs for disease control in aquaculture.

Recent progress in degradation and stabilization of organic solar cells

NASA Astrophysics Data System (ADS)

Cao, Huanqi; He, Weidong; Mao, Yiwu; Lin, Xiao; Ishikawa, Ken; Dickerson, James H.; Hess, Wayne P.

2014-10-01

Stability is of paramount importance in organic semiconductor devices, especially in organic solar cells (OSCs). Serious degradation in air limits wide applications of these flexible, light-weight and low-cost power-generation devices. Studying the stability of organic solar cells will help us understand degradation mechanisms and further improve the stability of these devices. There are many investigations into the efficiency and stability of OSCs. The efficiency and stability of devices even of the same photoactive materials are scattered in different papers. In particular, the extrinsic degradation that mainly occurs near the interface between the organic layer and the cathode is a major stability concern. In the past few years, researchers have developed many new cathodes and cathode buffer layers, some of which have astonishingly improved the stability of OSCs. In this review article, we discuss the recent developments of these materials and summarize recent progresses in the study of the degradation/stability of OSCs, with emphasis on the extrinsic degradation/stability that is related to the intrusion of oxygen and water. The review provides detailed insight into the current status of research on the stability of OSCs and seeks to facilitate the development of highly-efficient OSCs with enhanced stability.

A Comparison of Assessment Tools: Is Direct Observation an Improvement Over Objective Structured Clinical Examinations for Communications Skills Evaluation?

PubMed

Goch, Abraham M; Karia, Raj; Taormina, David; Kalet, Adina; Zuckerman, Joseph; Egol, Kenneth A; Phillips, Donna

2018-04-01

Evaluation of resident physicians' communications skills is a challenging task and is increasingly accomplished with standardized examinations. There exists a need to identify the effective, efficient methods for assessment of communications skills. We compared objective structured clinical examination (OSCE) and direct observation as approaches for assessing resident communications skills. We conducted a retrospective cohort analysis of orthopaedic surgery resident physicians at a single tertiary care academic institution, using the Institute for Healthcare Communication "4 Es" model for effective communication. Data were collected between 2011 and 2015. A total of 28 residents, each with OSCE and complete direct observation assessment checklists, were included in the analysis. Residents were included if they had 1 OSCE assessment and 2 or more complete direct observation assessments. There were 28 of a possible 59 residents (47%) included. A total of 89% (25 of 28) of residents passed the communications skills OSCE; only 54% (15 of 28) of residents passed the direct observation communications assessment. There was a positive, moderate correlation between OSCE and direct observation scores overall ( r  = 0.415, P  = .028). There was no agreement between OSCE and direct observation in categorizing residents into passing and failing scores (κ = 0.205, P  = .16), after adjusting for chance agreement. Our results suggest that OSCE and direct observation tools provide different insights into resident communications skills (simulation of rare and challenging situations versus real-life daily encounters), and may provide useful perspectives on resident communications skills in different contexts.

Assessment of current undergraduate anesthesia course in a Saudi University

PubMed Central

Shams, Tarek; El-Masry, Ragaa; al Wadani, Hamed; Amr, Mostafa

2013-01-01

Background: The assessment of the anesthesia course in our university comprises Objective Structured Clinical Examinations (OSCEs), in conjunction with portfolio and multiple-choice questions (MCQ). The objective of this study was to evaluate the outcome of different forms of anesthesia course assessment among 5th year medical students in our university, as well as study the influence of gender on student performance in anesthesia. Methods: We examined the performance of 154, 5th year medical students through OSCE, portfolios, and MCQ. Results: The score ranges in the portfolio, OSCE, and MCQs were 16-24, 4.2-28.9, and 15.5-44.5, respectively. There was highly significant difference in scores in relation to gender in all assessments other than the written one (P=0.000 for Portfolio, OSCE, and Total exam, whereas P=0.164 for written exam). In the generated linear regression model, OSCE alone could predict 86.4% of the total mark if used alone. In addition, if the score of the written examination is added, OSCE will drop to 57.2% and the written exam will be 56.8% of the total mark. Conclusions: This study demonstrates that different clinical methods used to assess medical students during their anesthesia course were consistent and integrated. The performance of female was superior to male in OSCE and portfolio. This information is the basis for improving educational and assessment standards in anesthesiology and for introducing a platform for developing modern learning media in countries with dearth of anesthesia personnel. PMID:23956708

Significance of Objective Structured Clinical Examinations to Plastic Surgery Residency Training.

PubMed

Simmons, Brian J; Zoghbi, Yasmina; Askari, Morad; Birnbach, David J; Shekhter, Ilya; Thaller, Seth R

2017-09-01

Objective structured clinical examinations (OSCEs) have proven to be a powerful tool. They possess more than a 30-year track record in assessing the competency of medical students, residents, and fellows. Objective structured clinical examinations have been used successfully in a variety of medical specialties, including surgery. They have recently found their way into the subspecialty of plastic surgery. This article uses a systematic review of the available literature on OSCEs and their recent use in plastic surgery. It incorporates survey results assessing program directors' views on the use of OSCEs. Approximately 40% of programs surveyed use OSCEs to assess the Accreditation Council for Graduate Medical Education core competencies. We found that 40% use OSCEs to evaluate specific plastic surgery milestones. Objective structured clinical examinations are usually performed annually. They cost anywhere between $100 and more than $1000 per resident. Four milestones giving residents the most difficulties on OSCEs were congenital anomalies, noncancer breast surgery, breast reconstruction, and practice-based learning and improvement. It was determined that challenges with milestones were due to lack of adequate general knowledge and surgical ward patient care, as well as deficits in professionalism and system-based problems. Programs were able to remediate weakness found by OSCEs using a variety of methods. Objective structured clinical examinations offer a unique tool to objectively assess the proficiency of residents in key areas of the Accreditation Council for Graduate Medical Education core competencies. In addition, they can be used to assess the specific milestones that plastic surgery residents must meet. This allows programs to identify and improve identified areas of weakness.

Recommended design and fabrication sequence of AMTEC test assembly

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Kumar, V.; Noravian, H.

1998-01-01

A series of previous OSC papers described: 1) a novel methodology for the coupled thermal, fluid flow, and electrical analysis of multitube AMTEC (Alkali Metal Thermal-to-Electric Conversion) cells; 2) the application of that methodology to determine the effect of numerous design variations on the cell{close_quote}s performance, leading to selection and performance characterization of an OSC-recommended cell design; and 3) the design, analysis, and characterization of an OSC-generated power system design combining sixteen of the above AMTEC cells with two or three GPHS (General Purpose Heat Source) radioisotope heat source modules, and the applicability of those power systems to future spacemore » missions ({ital e.g.} Pluto Express and Europa Orbiter) under consideration by NASA. The OSC system design studies demonstrated the critical importance of the thermal insulation subsystem, and culminated in a design in which the eight AMTEC cells on each end of the heat source stack are embedded in Min-K fibrous insulation, and the Min-K and the GPHS modules are surrounded by graded-length Mo multifoil insulation. The present paper depicts the OSC-recommended AMTEC cell and generator designs, and identifies the need for an electrically heated (scaled-down but otherwise prototypic) test assembly for the experimental validation of the generator{close_quote}s system performance predictions. It then describes the design of an OSC-recommended test assembly consisting of an electrical heater enclosed in a graphite box to simulate the radioisotope heat source, four series-connected prototypic AMTEC cells of the OSC-recommended configuration, and a prototypic hybrid insulation package consisting of Min-K and graded-length Mo multifoils. Finally, the paper describes and illustrates an OSC-recommended detailed fabrication sequence and procedure for the above cell and test assembly. That fabrication procedure is being implemented by AMPS, Inc. with the support of DOE

Understanding the Halogenation Effects in Diketopyrrolopyrrole-Based Small Molecule Photovoltaics.

PubMed

Sun, Shi-Xin; Huo, Yong; Li, Miao-Miao; Hu, Xiaowen; Zhang, Hai-Jun; Zhang, You-Wen; Zhang, You-Dan; Chen, Xiao-Long; Shi, Zi-Fa; Gong, Xiong; Chen, Yongsheng; Zhang, Hao-Li

2015-09-16

Two molecules containing a central diketopyrrolopyrrole and two oligothiophene units have been designed and synthesized. Comparisons between the molecules containing terminal F (FDPP) and Cl (CDPP) atoms allowed us to evaluate the effects of halogenation on the photovoltaic properties of the small molecule organic solar cells (OSCs). The OSCs devices employing FDPP:PC71BM films showed power conversion efficiencies up to 4.32%, suggesting that fluorination is an efficient method for constructing small molecules for OSCs.

Low-Temperature Preparation of Tungsten Oxide Anode Buffer Layer via Ultrasonic Spray Pyrolysis Method for Large-Area Organic Solar Cells

PubMed Central

Ji, Ran; Zheng, Ding; Zhou, Chang; Cheng, Jiang; Yu, Junsheng; Li, Lu

2017-01-01

Tungsten oxide (WO3) is prepared by a low-temperature ultrasonic spray pyrolysis method in air atmosphere, and it is used as an anode buffer layer (ABL) for organic solar cells (OSCs). The properties of the WO3 transition metal oxide material as well as the mechanism of ultrasonic spray pyrolysis processes are investigated. The results show that the ultrasonic spray pyrolysized WO3 ABL exhibits low roughness, matched energy level, and high conductivity, which results in high charge transport efficiency and suppressive recombination in OSCs. As a result, compared to the OSCs based on vacuum thermal evaporated WO3, a higher power conversion efficiency of 3.63% is reached with low-temperature ultrasonic spray pyrolysized WO3 ABL. Furthermore, the mostly spray-coated OSCs with large area was fabricated, which has a power conversion efficiency of ~1%. This work significantly enhances our understanding of the preparation and application of low temperature-processed WO3, and highlights the potential of large area, all spray coated OSCs for sustainable commercial fabrication. PMID:28773177

76 FR 5482 - Belarus Sanctions Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-01

... Organization for Security and Co-operation in Europe's (OSCE) Office for Democratic Institutions and Human... the Government of Belarus to close the Minsk office of the OSCE, OFAC is amending the Belarus...

75 FR 75615 - Helsinki Human Rights Day, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-03

... Organization for Security and Cooperation in Europe (OSCE), still serve as a beacon to all who strive for... their compliance with their OSCE commitments. The Helsinki Final Act, with its affirmation of...

A new electrode design for ambipolar injection in organic semiconductors.

PubMed

Kanagasekaran, Thangavel; Shimotani, Hidekazu; Shimizu, Ryota; Hitosugi, Taro; Tanigaki, Katsumi

2017-10-17

Organic semiconductors have attracted much attention for low-cost, flexible and human-friendly optoelectronics. However, achieving high electron-injection efficiency is difficult from air-stable electrodes and cannot be equivalent to that of holes. Here, we present a novel concept of electrode composed of a bilayer of tetratetracontane (TTC) and polycrystalline organic semiconductors (pc-OSC) covered by a metal layer. Field-effect transistors of single-crystal organic semiconductors with the new electrodes of M/pc-OSC/TTC (M: Ca or Au) show both highly efficient electron and hole injection. Contact resistance for electron injection from Au/pc-OSC/TTC and hole injection from Ca/pc-OSC/TTC are comparable to those for electron injection from Ca and hole injection from Au, respectively. Furthermore, the highest field-effect mobilities of holes (22 cm 2  V -1  s -1 ) and electrons (5.0 cm 2  V -1  s -1 ) are observed in rubrene among field-effect transistors with electrodes so far proposed by employing Ca/pc-OSC/TTC and Au/pc-OSC/TTC electrodes for electron and hole injection, respectively.One of technological challenges building organic electronics is efficient injection of electrons at metal-semiconductor interfaces compared to that of holes. The authors show an air-stable electrode design with induced gap states, which support Fermi level pinning and thus ambipolar carrier injection.

Impact of Electrodes on Recombination in Bulk Heterojunction Organic Solar Cells

PubMed Central

2018-01-01

In recent years, the efficiency of organic solar cells (OSCs) has increased to more than 13%, although different barriers are on the way for reaching higher efficiencies. One crucial barrier is the recombination of charge carriers, which can either occur as the bulk recombination of photogenerated charges or the recombination of photogenerated charges and electrodic induced charges (EICs). This work studies the impact of EICs on the recombination lifetime in OSCs. To this end, the net recombination lifetime of photogenerated charge carriers in the presence of EICs is measured by means of conventional and newly developed transient photovoltage techniques. Moreover, a new approach has been introduced to exclusively measure the bulk recombination lifetime, i.e., in the absence of EICs; this approach was conducted by depositing transparent insulating layers on both sides of the OSC active layer. An examination of these approaches on OSCs with different active layer materials, thicknesses, and varying light intensities determined that the EICs can only reduce the recombination lifetime of the photogenerated charges in OSCs with very weak recombination strength. This work supports that for OSCs with highly reduced recombination strength, eliminating the recombination of photogenerated charges and EICs is critical for achieving better performance. Therefore, the use of a proper blocking layer suppresses EIC recombination in systems with very weak recombination. PMID:29546982

Optical absorption enhancement by inserting ZnO optical spacer in plasmonic organic solar cells

NASA Astrophysics Data System (ADS)

N'Konou, Kekeli; Torchio, Philippe

2018-01-01

Optical absorption enhancement (AE) using coupled optical spacer and plasmonic effects in standard and inverted organic solar cells (OSCs) are demonstrated using the finite-difference time-domain numerical method. The influence of an added zinc oxide (ZnO) optical spacer layer inserted below the active layer in standard architecture is first theoretically investigated while the influence of varying the ZnO cathodic buffer layer thickness in inverted design is studied on AE. Then, the embedding of a square periodic array of core-shell silver-silica nanospheres (Ag@SiO2 NSs) at different positions in standard and inverted OSCs is performed while AE and short-circuit current density (Jsc) are calculated. As a result of previous combined effects, the optimized standard plasmonic OSCs present 15% and 79.45% enhancement in J over the reference with and without ZnO optical spacer layer, respectively, and a 16% increase of AE when Ag@SiO2 NSs are placed on top of the PEDOT:PSS layer. Compared to the inverted OSC reference, the plasmonic OSCs present 26% and 27% enhancement in J and AE, respectively, when the Ag@SiO2 NSs are located on top of the ZnO layer. Furthermore, the spatial position of these NSs in such OSCs is a key parameter for increasing light absorption via enhanced electromagnetic field distribution.

3 CFR 8608 - Proclamation 8608 of November 30, 2010. Helsinki Human Rights Day, 2010

Code of Federal Regulations, 2011 CFR

2011-01-01

... institutionalized in the Organization for Security and Cooperation in Europe (OSCE), still serve as a beacon to all... states to reexamine their compliance with their OSCE commitments. The Helsinki Final Act, with its...

Surgery Clerkship Evaluations Are Insufficient for Clinical Skills Appraisal: The Value of a Medical Student Surgical Objective Structured Clinical Examination.

PubMed

Butler, Kathryn L; Hirsh, David A; Petrusa, Emil R; Yeh, D Dante; Stearns, Dana; Sloane, David E; Linder, Jeffrey A; Basu, Gaurab; Thompson, Lisa A; de Moya, Marc A

Optimal methods for medical student assessment in surgery remain elusive. Faculty- and housestaff-written evaluations constitute the chief means of student assessment in medical education. However, numerous studies show that this approach has poor specificity and a high degree of subjectivity. We hypothesized that an objective structured clinical examination (OSCE) in the surgery clerkship would provide additional data on student performance that would confirm or augment other measures of assessment. We retrospectively reviewed data from OSCEs, National Board of Medical Examiners shelf examinations, oral presentations, and written evaluations for 51 third-year Harvard Medical School students rotating in surgery at Massachusetts General Hospital from 2014 to 2015. We expressed correlations between numeric variables in Pearson coefficients, stratified differences between rater groups by one-way analysis of variance, and compared percentages with 2-sample t-tests. We examined commentary from both OSCE and clinical written evaluations through textual analysis and summarized these results in percentages. OSCE scores and clinical evaluation scores correlated poorly with each other, as well as with shelf examination scores and oral presentation grades. Textual analysis of clinical evaluation comments revealed a heavy emphasis on motivational factors and praise, whereas OSCE written comments focused on cognitive processes, patient management, and methods to improve performance. In this single-center study, an OSCE provided clinical skills data that were not captured elsewhere in the surgery clerkship. Textual analysis of faculty evaluations reflected an emphasis on interpersonal skills, rather than appraisal of clinical acumen. These findings suggest complementary roles of faculty evaluations and OSCEs in medical student assessment. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Communication Skills in Candidates for Accreditation in Rheumatology Are Correlated With Candidate's Performance in the Objective Structured Clinical Examination.

PubMed

Pascual-Ramos, Virginia; Flores-Alvarado, Diana Elsa; Portela-Hernández, Margarita; Maldonado-Velázquez, María Del Rocío; Amezcua-Guerra, Luis Manuel; López-Zepeda, Judith; Álvarez, Everardo; Rubio, Nadina; Lastra, Olga Vera; Saavedra, Miguel Ángel; Arce-Salinas, César Alejandro

2017-07-26

The Mexican Accreditation Council for Rheumatology annually certifies trainees in Rheumatology using a multiple-choice test and an objective structured clinical examination (OSCE). Since 2015, candidate's communication skills (CS) have been rated by both patients and by physician examiners and correlated with results on the OSCE. This study compared the CS from candidates to annual accreditation in Rheumatology as rated by patients and by physician examiners, and assessed whether these correlated with candidate's performance in the OSCE. From 2015 to 2017, 8areas of CS were evaluated using a Likert scale, in each OSCE station that involved a patient. Both patient and physician evaluators were trained annually and their evaluations were performed blindly. The associations were calculated using the Pearson correlation coefficient. In general, candidates were given high CS scores; the scores from patients of the candidate's CS were better than those of physician examiners; within the majority of the stations, both scores were found to correlate moderately. In addition, the scoring of CS correlated with trainee performance at the corresponding OSCE station. Interestingly, better correlations were found when the skills were rated by the patients compared to physician scores. The average CS score was correlated with the overall OSCE performance for each trainee, but not with the multiple-choice test, except in the 2017 accreditation process, when a weak correlation was found. CS assessed during a national accreditation process correlated with the candidate's performance at the station level and with the overall OSCE. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Human microsomal cyttrochrome P450-mediated reduction of oxysophocarpine, an active and highly toxic constituent derived from Sophora flavescens species, and its intestinal absorption and metabolism in rat.

PubMed

Wu, Lili; Zhong, Wanping; Liu, Junjin; Han, Weichao; Zhong, Shilong; Wei, Qiang; Liu, Shuwen; Tang, Lan

2015-09-01

Oxysophocarpine (OSC), an active and toxic quinolizidine alkaloid, is highly valued in Sophora flavescens Ait. and Subprostrate sophora Root. OSC is used to treat inflammation and hepatitis for thousands of years in China. This study aims to investigate the CYP450-mediated reduction responsible for metabolizing OSC and to evaluate the absorption and metabolism of OSC in rat in situ. Four metabolites were identified, with sophocarpine (SC) as the major metabolite. SC formation was rapid in human and rat liver microsomes (HLMs and RLMs, respectively). The reduction rates in the liver are two fold higher than in the intestine, both in humans and rats. In HLMs, inhibitors of CYP2C9, 3A4/5, 2D6, and 2B6 had strong inhibitory effects on SC formation. Meanwhile, inhibitors of CYP3A and CYP2D6 had significant inhibition on SC formation in RLMs. Human recombinant CYP3A4/5, 2B6, 2D6, and 2C9 contributed significantly to SC production. The permeability in rat intestine and the excretion rates of metabolites were highest in the duodenum (p<0.05), and the absorbed amount of OSC in duodenum and jejunum was concentration-dependent. The metabolism could be significantly decreased by CYP3A inhibitor ketoconazole. In conclusion, the liver was the main organ responsible for OSC metabolism. First-pass metabolism via CYP3A4/5, 2B6, 2D6, and 2C9 may be the main reason for the poor OSC bioavailability. Copyright © 2015 Elsevier B.V. All rights reserved.

Order effects in high stakes undergraduate examinations: an analysis of 5 years of administrative data in one UK medical school.

PubMed

Burt, Jenni; Abel, Gary; Barclay, Matt; Evans, Robert; Benson, John; Gurnell, Mark

2016-10-11

To investigate the association between student performance in undergraduate objective structured clinical examinations (OSCEs) and the examination schedule to which they were assigned to undertake these examinations. Analysis of routinely collected data. One UK medical school. 2331 OSCEs of 3 different types (obstetrics OSCE, paediatrics OSCE and simulated clinical encounter examination OSCE) between 2009 and 2013. Students were not quarantined between examinations. (1) Pass rates by day examination started, (2) pass rates by day station undertaken and (3) mean scores by day examination started. We found no evidence that pass rates differed according to the day on which the examination was started by a candidate in any of the examinations considered (p>0.1 for all). There was evidence (p=0.013) that students were more likely to pass individual stations on the second day of the paediatrics OSCE (OR 1.27, 95% CI 1.05 to 1.54). In the cases of the simulated clinical encounter examination and the obstetrics and gynaecology OSCEs, there was no (p=0.42) or very weak evidence (p=0.099), respectively, of any such variation in the probability of passing individual stations according to the day they were attempted. There was no evidence that mean scores varied by day apart from the paediatric OSCE, where slightly higher scores were achieved on the second day of the examination. There is little evidence that different examination schedules have a consistent effect on pass rates or mean scores: students starting the examinations later were not consistently more or less likely to pass or score more highly than those starting earlier. The practice of quarantining students to prevent communication with (and subsequent unfair advantage for) subsequent examination cohorts is unlikely to be required. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

How does preclinical laboratory training impact physical examination skills during the first clinical year? A retrospective analysis of routinely collected objective structured clinical examination scores among the first two matriculating classes of a reformed curriculum in one Polish medical school

PubMed Central

Świerszcz, Jolanta; Stalmach-Przygoda, Agata; Kuźma, Marcin; Jabłoński, Konrad; Cegielny, Tomasz; Skrzypek, Agnieszka; Wieczorek-Surdacka, Ewa; Kruszelnicka, Olga; Chmura, Kaja; Chyrchel, Bernadeta; Surdacki, Andrzej; Nowakowski, Michał

2017-01-01

Objective As a result of a curriculum reform launched in 2012 at our institution, preclinical training was shortened to 2 years instead of the traditional 3 years, creating additional incentives to optimise teaching methods. In accordance with the new curriculum, a semester-long preclinical module of clinical skills (CS) laboratory training takes place in the second year of study, while an introductory clinical course (ie, brief introductory clerkships) is scheduled for the Fall semester of the third year. Objective structured clinical examinations (OSCEs) are carried out at the conclusion of both the preclinical module and the introductory clinical course. Our aim was to compare the scores at physical examination stations between the first and second matriculating classes of a newly reformed curriculum on preclinical second-year OSCEs and early clinical third-year OSCEs. Design Analysis of routinely collected data. Setting One Polish medical school. Participants Complete OSCE records for 462 second-year students and 445 third-year students. Outcome measures OSCE scores by matriculation year. Results In comparison to the first class of the newly reformed curriculum, significantly higher (ie, better) OSCE scores were observed for those students who matriculated in 2013, a year after implementing the reformed curriculum. This finding was consistent for both second-year and third-year cohorts. Additionally, the magnitude of the improvement in median third-year OSCE scores was proportional to the corresponding advancement in preceding second-year preclinical OSCE scores for each of two different sets of physical examination tasks. In contrast, no significant difference was noted between the academic years in the ability to interpret laboratory data or ECG — tasks which had not been included in the second-year preclinical training. Conclusion Our results suggest the importance of preclinical training in a CS laboratory to improve students’ competence in

How does preclinical laboratory training impact physical examination skills during the first clinical year? A retrospective analysis of routinely collected objective structured clinical examination scores among the first two matriculating classes of a reformed curriculum in one Polish medical school.

PubMed

Świerszcz, Jolanta; Stalmach-Przygoda, Agata; Kuźma, Marcin; Jabłoński, Konrad; Cegielny, Tomasz; Skrzypek, Agnieszka; Wieczorek-Surdacka, Ewa; Kruszelnicka, Olga; Chmura, Kaja; Chyrchel, Bernadeta; Surdacki, Andrzej; Nowakowski, Michał

2017-09-01

As a result of a curriculum reform launched in 2012 at our institution, preclinical training was shortened to 2 years instead of the traditional 3 years, creating additional incentives to optimise teaching methods. In accordance with the new curriculum, a semester-long preclinical module of clinical skills (CS) laboratory training takes place in the second year of study, while an introductory clinical course (ie, brief introductory clerkships) is scheduled for the Fall semester of the third year. Objective structured clinical examinations (OSCEs) are carried out at the conclusion of both the preclinical module and the introductory clinical course. Our aim was to compare the scores at physical examination stations between the first and second matriculating classes of a newly reformed curriculum on preclinical second-year OSCEs and early clinical third-year OSCEs. Analysis of routinely collected data. One Polish medical school. Complete OSCE records for 462 second-year students and 445 third-year students. OSCE scores by matriculation year. In comparison to the first class of the newly reformed curriculum, significantly higher (ie, better) OSCE scores were observed for those students who matriculated in 2013, a year after implementing the reformed curriculum. This finding was consistent for both second-year and third-year cohorts. Additionally, the magnitude of the improvement in median third-year OSCE scores was proportional to the corresponding advancement in preceding second-year preclinical OSCE scores for each of two different sets of physical examination tasks. In contrast, no significant difference was noted between the academic years in the ability to interpret laboratory data or ECG - tasks which had not been included in the second-year preclinical training. Our results suggest the importance of preclinical training in a CS laboratory to improve students' competence in physical examination at the completion of introductory clinical clerkships during

Objectivity in subjectivity: do students' self and peer assessments correlate with examiners' subjective and objective assessment in clinical skills? A prospective study.

PubMed

Inayah, A'man Talal; Anwer, Lucman A; Shareef, Mohammad Abrar; Nurhussen, Akram; Alkabbani, Haifa Mazen; Alzahrani, Alhanouf A; Obad, Adam Subait; Zafar, Muhammad; Afsar, Nasir Ali

2017-05-09

The qualitative subjective assessment has been exercised either by self-reflection (self-assessment (SA)) or by an observer (peer assessment (PA)) and is considered to play an important role in students' development. The objectivity of PA and SA by students as well as those by faculty examiners has remained debated. This matters most when it comes to a high-stakes examination. We explored the degree of objectivity in PA, SA, as well as the global rating by examiners being Examiners' Subjective Assessment (ESA) compared with Objective Structured Clinical Examinations (OSCE). Prospective cohort study. Undergraduate medical students at Alfaisal University, Riyadh. All second-year medical students (n=164) of genders, taking a course to learn clinical history taking and general physical examination. A Likert scale questionnaire was distributed among the participants during selected clinical skills sessions. Each student was evaluated randomly by peers (PA) as well as by himself/herself (SA). Two OSCEs were conducted where students were assessed by an examiner objectively as well as subjectively (ESA) for a global rating of confidence and well-preparedness. OSCE-1 had fewer topics and stations, whereas OSCE-2 was terminal and full scale. OSCE-1 (B=0.10) and ESA (B=8.16) predicted OSCE-2 scores. 'No nervousness' in PA (r=0.185, p=0.018) and 'confidence' in SA (r=0.207, p=0.008) correlated with 'confidence' in ESA. In 'well-preparedness', SA correlated with ESA (r=0.234, p=0.003). OSCE-1 and ESA predicted students' performance in the OSCE-2, a high-stakes evaluation, indicating practical 'objectivity' in ESA, whereas SA and PA had minimal predictive role. Certain components of SA and PA correlated with ESA, suggesting partial objectivity given the limited objectiveness of ESA. Such difference in 'qualitative' objectivity probably reflects experience. Thus, subjective assessment can be used with some degree of objectivity for continuous assessment. © Article author(s) (or

G-CLEAN OSC-1809

EPA Pesticide Factsheets

Technical product bulletin: aka OIL SPILL CLEANUP, this surface washing agent may be applied liberally to heavily weathered oil on rocks or beaches/sand, vegetation, or at full strength on tar balls. Best results if allowed to soak, agitated, or reapplied.

Voluntary attendance of small-group brainstorming tutoring courses intensify new clerk's "excellence in clinical care": a pilot study.

PubMed

Yang, Ling-Yu; Huang, Chia-Chang; Hsu, Hui-Chi; Yang, Ying-Ying; Chang, Ching-Chi; Chuang, Chiao-Lin; Lee, Wei-Shin; Liang, Jen-Feng; Cheng, Hao Min; Huang, Chin-Chou; Lee, Fa-Yauh; Ho, Shung-Tai; Kirby, Ralph

2017-01-06

Clerkship provides a unique way of transferring the knowledge and skills gathered during medical school's curriculum into real-ward clinical care environment. The annual program evaluation has indicated that the training of clerks in diagnostic and clinical reasoning skills needed to be enhanced. Recently, "clinical excellence" program have been promoted in our institution to augment the excellence in clinical care of new clerks. Current study aims to evaluate whether this pilot program improve the "clinical excellence" of new clerks. In a pilot study, groups of new clerks in years 2013 and 2014 voluntarily attended either a small-group brainstorming course or a didactic classroom tutoring courses as part of their 3-month internal medicine clinical rotation block. A third group of new clerks did not join either of the above courses and this group served as the control group. Pre-block/post-block self-assessment and post-block 5-station mini-Objective Subjective Clinical Examinations (OSCEs) were used to evaluate the effectiveness of these two additional courses that trained diagnostic and clinical reasoning skills. Overtime, the percentages of new clerks that attended voluntarily either the small-group brainstorming or classroom tutoring courses were increased. Higher post-block self-assessed diagnostic and clinical reasoning skill scores were found among individuals who attended the small-group brainstorming courses compared to either the didactic group or the control group. In a corresponding manner, the small-group brainstorming group obtained higher summary OSCE diag and OSCE reason scores than either the didactic group or control group. For all basic images/laboratory OSCE stations, the individual diagnostic skill (OSCE diag ) scores of the small-group brainstorming group were higher than those of the didactic group. By way of contrast, only the clinical reasoning skill (OSCE reason ) scores of the basic electrocardiogram and complete blood count�

Assessing patient-centered care: one approach to health disparities education.

PubMed

Wilkerson, LuAnn; Fung, Cha-Chi; May, Win; Elliott, Donna

2010-05-01

Patient-centered care has been described as one approach to cultural competency education that could reduce racial and ethnic health disparities by preparing providers to deliver care that is respectful and responsive to the preferences of each patient. In order to evaluate the effectiveness of a curriculum in teaching patient-centered care (PCC) behaviors to medical students, we drew on the work of Kleinman, Eisenberg, and Good to develop a scale that could be embedded across cases in an objective structured clinical examination (OSCE). To compare the reliability, validity, and feasibility of an embedded patient-centered care scale with the use of a single culturally challenging case in measuring students' use of PCC behaviors as part of a comprehensive OSCE. A total of 322 students from two California medical schools participated in the OSCE as beginning seniors. Cronbach's alpha was used to assess the internal consistency of each approach. Construct validity was addressed by establishing convergent and divergent validity using the cultural challenge case total score and OSCE component scores. Feasibility assessment considered cost and training needs for the standardized patients (SPs). Medical students demonstrated a moderate level of patient-centered skill (mean = 63%, SD = 11%). The PCC Scale demonstrated an acceptable level of internal consistency (alpha = 0.68) over the single case scale (alpha = 0.60). Both convergent and divergent validities were established through low to moderate correlation coefficients. The insertion of PCC items across multiple cases in a comprehensive OSCE can provide a reliable estimate of students' use of PCC behaviors without incurring extra costs associated with implementing a special cross-cultural OSCE. This approach is particularly feasible when an OSCE is already part of the standard assessment of clinical skills. Reliability may be increased with an additional investment in SP training.

Short communication: Persistent socio-economic inequality in frequent headache among Danish adolescents from 1991 to 2014.

PubMed

Holstein, B E; Andersen, A; Denbaek, A M; Johansen, A; Michelsen, S I; Due, P

2018-05-01

The association between socio-economic status (SES) and headache among adolescents is an understudied issue, and no study has examined whether such an association changes over time. The aim was to examine trends in socio-economic inequality in frequent headache among 11- to 15-year-olds in Denmark from 1991 to 2014, using occupational social class (OSC) as indicator of SES. The study applies data from the Danish part of the international Health Behaviour in School-aged Children (HBSC) study. HBSC includes nationally representative samples of 11-, 13- and 15-year-olds. This study combines data from seven data survey years from 1991 to 2014, participation rate 88.6%, n = 31,102. We report absolute inequality as per cent difference in frequent headache between high and low OSC and relative inequality as odds ratio for frequent headache by OSC. In the entire study population, 10.4% reported frequent headache. There was a significant increase in frequent headache from 8.0% in 1991 to 12.9% in 2014, test for trend, p < 0.0001. This increasing trend was significant in all OSCs. The prevalence of frequent headache was significantly higher in low than high OSC, OR = 1.50 (95% CI: 1.34-1.67). This socio-economic inequality in frequent headache was persistent from 1991 to 2014. There was a significant and persistent socio-economic inequality, i.e. increasing prevalence of frequent headache with decreasing OSC. The association between socio-economic position and headache did not significantly change over time, i.e. the statistical interaction between OSC and survey year was insignificant. The prevalence of frequent headache among adolescents increases with decreasing SES. This socio-economic inequality has been persistent among adolescents in Denmark from 1991 to 2014. Clinicians should be aware of this social inequality. © 2018 European Pain Federation - EFIC®.

Anti-inflammatory and anti-endotoxin properties of peptides derived from the carboxy-terminal region of a defensin from the tick Ornithodoros savignyi.

PubMed

Malan, Melissa; Serem, June C; Bester, Megan J; Neitz, Albert W H; Gaspar, Anabella R M

2016-01-01

Antimicrobial peptides are small cationic peptides that possess a large spectrum of bioactivities, including antimicrobial, anti-inflammatory and antioxidant activities. Several antimicrobial peptides are known to inhibit lipopolysaccharide (LPS)-induced inflammation in vitro and to protect animals from sepsis. In this study, the cellular anti-inflammatory and anti-endotoxin activities of Os and Os-C, peptides derived from the carboxy-terminal of a tick defensin, were investigated. Both Os and Os-C were found to bind LPS in vitro, albeit to a lesser extent than polymyxin B and melittin, known endotoxin-binding peptides. Binding to LPS was found to reduce the bactericidal activity of Os and Os-C against Escherichia coli confirming the affinity of both peptides for LPS. At a concentration of 25 µM, the nitric oxide (NO) scavenging activity of Os was higher than glutathione, a known NO scavenger. In contrast, Os-C showed no scavenging activity. Os and Os-C inhibited LPS/IFN-γ induced NO and TNF-α production in RAW 264.7 cells in a concentration-dependent manner, with no cellular toxicity even at a concentration of 100 µM. Although inhibition of NO and TNF-α secretion was more pronounced for melittin and polymyxin B, significant cytotoxicity was observed at concentrations of 1.56 µM and 25 µM for melittin and polymyxin B, respectively. In addition, Os, Os-C and glutathione protected RAW 264.7 cells from oxidative damage at concentrations as low as 25 µM. This study identified that besides previously reported antibacterial activity of Os and Os-C, both peptides have in addition anti-inflammatory and anti-endotoxin properties. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

Clinical examiners, simulated patients, and student self-assessed empathy in medical students during a psychiatry objective structured clinical examination.

PubMed

O'Connor, Karen; King, Romaine; Malone, Kevin M; Guerandel, Allys

2014-08-01

This study aims to assess and compare objective and subjective scores of empathy in final-year medical students by using firstly a validated student self-assessment just prior to the psychiatry objective structured clinical examination (OSCE), and then comparing this to clinical examiner's and simulated patient's (SP's) assessments of empathy of students using a Global Rating of Empathy scale (GRE) during a psychiatry OSCE. In 2011, all final-year medical students in the University College Dublin were invited to complete a subjective, self-assessed empathy questionnaire (The Jefferson scale of physician empathy-student version (JSPE-S)). They were also assessed for empathy in four OSCEs by the clinical examiner and the SP acting in that OSCE scenario. Included in the analysis were 163 of 184 final-year students JSPE-S (88.6%) questionnaires. The female students scores on the JSPE-S were significantly higher than those of their male peers (t=3.34, p=0.001). Concurrent validity was greater between the SPs' assessments of empathy in the OSCE and the JSPE-S score than between the clinical examiners assessments of empathy and the JSPE-S score (r=0.23, p<0.005; r=0.14, p<0.08). Inter-rater reliability of SP's and clinical examiner's using the GRE was found to be high (F=0.868 (df=171, 171), p value<0.001). SPs may be valid assessors of empathy in medical students during an OSCE.

Mapping Direct Observations From Objective Structured Clinical Examinations to the Milestones Across Specialties.

PubMed

Baker-Genaw, Kimberly; Kokas, Maria S; Ahsan, Syed F; Darnley-Fisch, Deborah; Drake, Sean; Goyal, Nikhil; Inamdar, Kedar; Moutzouros, Vasilios; Prabhakar, Deepak; Rolland, Laurie; Sangha, Roopina; Shreve, Maria; Woodward, Ann

2016-07-01

Little is known about residents' performance on the milestones at the institutional level. Our institution formed a work group to explore this using an institutional-level curriculum and residents' evaluation of the milestones. We assessed whether beginner-level milestones for interpersonal and communication skills (ICS) related to observable behaviors in ICS-focused objective structured clinical examinations (OSCEs) for postgraduate year (PGY) 1 residents across specialties. The work group compared ICS subcompetencies across 12 programs to identify common beginner-level physician-patient communication milestones. The selected ICS milestone sets were compared for common language with the ICS-OSCE assessment tool-the Kalamazoo Essential Elements of Communication Checklist-Adapted (KEECC-A). To assess whether OSCE scores related to ICS milestone scores, all PGY-1 residents from programs that were part of Next Accreditation System Phase 1 were identified; their OSCE scores from July 2013 to June 2014 and ICS subcompetency scores from December 2014 were compared. The milestones for 10 specialties and the transitional year had at least 1 ICS subcompetency that related to physician-patient communication. The language of the ICS beginner-level milestones appears similar to behaviors outlined in the KEECC-A. All 60 residents with complete data received at least a beginner-level ICS subcompetency score and at least a satisfactory score on all 3 OSCEs. The ICS-OSCE scores for PGY-1 residents appear to relate to beginner-level milestones for physician-patient communication across multiple specialties.

Multiple mini-interview as a predictor of performance in the objective structured clinical examination among Physician Associates in the United Kingdom: a cohort study.

PubMed

Kumar, Narendra; Bhardwaj, Shailaja; Rahman, Eqram

2018-01-01

Patient satisfaction and health care outcomes are directly linked to useful communication skills. Therefore, excellent interpersonal skills are imperative for health care professionals. Multiple mini-interview (MMI) is designed as a selection tool to assess the communication skills of applicants in medical schools during the admission process. However, objective structured clinical examination (OSCE) assesses students' communication and clinical skills at the end of their academic terms. Recently, Anglia Ruskin University, Chelmsford, UK, adopted MMI in the selection process for the first cohort of MSc Physician Associate trainees for the academic year 2015-2016. This study aimed to determine the likelihood of MMI as a predictor of future performance of communication skills in the OSCE. The anonymous data of the average scores of communication skills attained in MMI and OSCE at the end of year 1 were collected for 30 students from the Physician Associate program team. Subsequently, Pearson's correlation was computed to determine the relationship between the average scores of communication skills attained in MMI, and OSCE during trimester 2 and trimester 3 by the Physician Associate trainees. The study showed positive correlation between the scores of communication skills attained in MMI and OSCE during trimester 2 ( r =0.956, n=30, p <0.001) and trimester 3 ( r =0.966, n=30, p <0.001). The study provides empirical evidence for the validity of MMI as a predictor of future performance of Physician Associate trainees' communication skills during subsequent OSCEs.

Education research: case logs in the assessment of medical students in the neurology outpatient clinic.

PubMed

Albert, Dara V; Brorson, James R; Amidei, Christina; Lukas, Rimas V

2014-04-22

Using outpatient neurology clinic case logs completed by medical students on neurology clerkships, we examined the impact of outpatient clinical encounter volume per student on outcomes of knowledge assessed by the National Board of Medical Examiners (NBME) Clinical Neurology Subject Examination and clinical skills assessed by the Objective Structured Clinical Examination (OSCE). Data from 394 medical students from July 2008 to June 2012, representing 9,791 patient encounters, were analyzed retrospectively. Pearson correlations were calculated examining the relationship between numbers of cases logged per student and performance on the NBME examination. Similarly, correlations between cases logged and performance on the OSCE, as well as on components of the OSCE (history, physical examination, clinical formulation), were evaluated. There was a correlation between the total number of cases logged per student and NBME examination scores (r = 0.142; p = 0.005) and OSCE scores (r = 0.136; p = 0.007). Total number of cases correlated with the clinical formulation component of the OSCE (r = 0.172; p = 0.001) but not the performance on history or physical examination components. The volume of cases logged by individual students in the outpatient clinic correlates with performance on measures of knowledge and clinical skill. In measurement of clinical skill, seeing a greater volume of patients in the outpatient clinic is related to improved clinical formulation on the OSCE. These findings may affect methods employed in assessment of medical students, residents, and fellows.

PERCEPTION OF FINAL YEAR MEDICAL STUDENTS ABOUT OBJECTIVE STRUCTURED CLINICAL EXAMINATION IN THE DEPARTMENT OF GENERAL SURGERY.

PubMed

Gelan, Engida Abebe; Essayas, Reiye; Gebressilase, Kibrom

2015-10-01

Background -Assessment of clinical skills of medical students has a central role in medical education yet the suit- able evaluation methods have persistently debated by educators and students. To assess perceptions of final year medical students about the Organized Structured Clinical Exam (OSCE) METHODS AND MATERIALS: A cross sectional study was performed to assess views of final year medical students who had taken the OSCE in the Department of Surgery of Mekelle University College of Health Sciences, as well as other traditional exam formats in other departments in the medical school. Of the 154 students who took the final qualifying exam, 127 (82.5%) responded to the survey. Eighty-four (66%) of the respondents were males. The OSCE was considered as the best assessment method of practical exams by 70 (55.1%) of the respondents, with the conventional long exam next in preference, by 47 (37%) students. For questions addressing the advantages of the OSCE, the average favorability score was between 4.2 - 4.6 out of Likert's type 5-point scale rating. Coverage of common and relevant topics, uniform student assessment, and communication skill assessment were items receiving high favorability scores by a particularly high percentage of students, (96.9%, 95.3% and 70.9% of all students, respectively). Most of the students favored the OSCE compared to conventional exam styles. Though the study should be confirmed. and extended in other settings, we recommend OSCE to be the main exam type for clinical year surgery examinations.

Undergraduate psychiatry students' attitudes towards teaching methods at an Irish university.

PubMed

Jabbar, F; Casey, P; Kelly, B D

2016-11-01

At University College Dublin, teaching in psychiatry includes clinical electives, lectures, small-group and problem-based teaching, consistent with international trends. To determine final-year psychiatry students' attitudes towards teaching methods. We distributed questionnaires to all final-year medical students in two classes (2008 and 2009), after final psychiatry examination (before results) and all of them participated (n = 111). Students' interest in psychiatry as a career increased during psychiatry teaching. Students rated objective structured clinical examination (OSCE) as the most useful element of teaching and examination. The most common learning style was "reflector"; the least common was "pragmatist". Two thirds believed teaching could be improved (increased patient contact) and 89 % reported that experience of psychiatry changed attitudes towards mental illness (increased understanding). Students' preference for OSCEs may reflect the closeness of OSCE as a form of learning to OSCE as a form of assessment: OSCEs both focus on specific clinical skills and help prepare for examinations. Future research could usefully examine the extent to which these findings are university-specific or instructor-dependent. Information on the consistency of various teaching, examination and modularisation methods would also be useful.

Socioeconomic position and occupational social class and their association with risky alcohol consumption among adolescents.

PubMed

Obradors-Rial, Núria; Ariza, Carles; Rajmil, Luis; Muntaner, Carles

2018-05-01

To compare different measures of socioeconomic position (SEP) and occupational social class (OSC) and to evaluate their association with risky alcohol consumption among adolescents attending the last mandatory secondary school (ages 15-17 years). This was a cross-sectional study. 1268 adolescents in Catalonia (Spain) participated in the study. Family affluence scale (FAS), parents' OSC, parents' level of education and monthly familiar income were used to compare socioeconomic indicators. Logistic regression analyses were conducted to evaluate socioeconomic variables and missing associated factors, and to observe the relation between each SEP variable and OSC adjusting by sociodemographic variables. Familiar income had more than 30% of missing values. OSC had the fewest missing values associated factors. Being immigrant was associated with all SEP missing values. All SEP measures were positively associated with risky alcohol consumption, yet the strength of these associations diminished after adjustment for sociodemographic variables. Weekly available money was the variable with the strongest association with risky alcohol consumption. OSC seems to be as good as the other indicators to assess adolescents' SEP. Adolescents with high SEP and those belonging to upper social classes reported higher levels of risky alcohol consumption.

Development of a Single-Pass Amplifier for an Optical Stochastic Cooling Proof-of-Principle Experiment at Fermilab's IOTA Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andorf, M. B.; Lebedev, V. A.; Piot, P.

2015-06-01

Optical stochastic cooling (OSC) is a method of beam cooling which is expected to provide cooling rates orders of magnitude larger than ordinary stochastic cooling. Light from an undulator (the pickup) is amplified and fed back onto the particle beam via another undulator (the kicker). Fermilab is currently exploring a possible proof-of-principle experiment of the OSC at the integrable-optics test accelerator (IOTA) ring. To implement effective OSC a good correction of phase distortions in the entire band of the optical amplifier is required. In this contribution we present progress in experimental characterization of phase distortions associated to a Titanium Sapphiremore » crystal laser-gain medium (a possible candidate gain medium for the OSC experiment to be performed at IOTA). We also discuss a possible option for a mid-IR amplifier« less

Stability of organic solar cells: challenges and strategies.

PubMed

Cheng, Pei; Zhan, Xiaowei

2016-05-03

Organic solar cells (OSCs) present some advantages, such as simple preparation, light weight, low cost and large-area flexible fabrication, and have attracted much attention in recent years. Although the power conversion efficiencies have exceeded 10%, the inferior device stability still remains a great challenge. In this review, we summarize the factors limiting the stability of OSCs, such as metastable morphology, diffusion of electrodes and buffer layers, oxygen and water, irradiation, heating and mechanical stress, and survey recent progress in strategies to increase the stability of OSCs, such as material design, device engineering of active layers, employing inverted geometry, optimizing buffer layers, using stable electrodes and encapsulation. Some research areas of device stability that may deserve further attention are also discussed to help readers understand the challenges and opportunities in achieving high efficiency and high stability of OSCs towards future industrial manufacture.

Determination of Oversulphated Chondroitin Sulphate and Dermatan Sulphate in unfractionated heparin by (1)H-NMR - Collaborative study for quantification and analytical determination of LoD.

PubMed

McEwen, I; Mulloy, B; Hellwig, E; Kozerski, L; Beyer, T; Holzgrabe, U; Wanko, R; Spieser, J-M; Rodomonte, A

2008-12-01

Oversulphated Chondroitin Sulphate (OSCS) and Dermatan Sulphate (DS) in unfractionated heparins can be identified by nuclear magnetic resonance spectrometry (NMR). The limit of detection (LoD) of OSCS is 0.1% relative to the heparin content. This LoD is obtained at a signal-to-noise ratio (S/N) of 2000:1 of the heparin methyl signal. Quantification is best obtained by comparing peak heights of the OSCS and heparin methyl signals. Reproducibility of less than 10% relative standard deviation (RSD) has been obtained. The accuracy of quantification was good.

Highly efficient and bendable organic solar cells using a three-dimensional transparent conducting electrode

NASA Astrophysics Data System (ADS)

Wang, Wei; Bae, Tae-Sung; Park, Yeon Hyun; Kim, Dong Ho; Lee, Sunghun; Min, Guanghui; Lee, Gun-Hwan; Song, Myungkwan; Yun, Jungheum

2014-05-01

A three-dimensional (3D) transparent conducting electrode, consisting of a quasi-periodic array of discrete indium-tin-oxide (ITO) nanoparticles superimposed on a highly conducting oxide-metal-oxide multilayer using ITO and silver oxide (AgOx) as oxide and metal layers, respectively, is synthesized on a polymer substrate and used as an anode in highly flexible organic solar cells (OSCs). The 3D electrode is fabricated using vacuum sputtering sequences to achieve self-assembly of distinct ITO nanoparticles on a continuous ITO-AgOx-ITO multilayer at room-temperature without applying conventional high-temperature vapour-liquid-solid growth, solution-based nanoparticle coating, or complicated nanopatterning techniques. Since the 3D electrode enhances the hole-extraction rate in OSCs owing to its high surface area and low effective series resistance for hole transport, OSCs based on this 3D electrode exhibit a power conversion efficiency that is 11-22% higher than that achievable in OSCs by means of conventional planar ITO film-type electrodes. A record high efficiency of 6.74% can be achieved in a bendable OSC fabricated on a poly(ethylene terephthalate) substrate.A three-dimensional (3D) transparent conducting electrode, consisting of a quasi-periodic array of discrete indium-tin-oxide (ITO) nanoparticles superimposed on a highly conducting oxide-metal-oxide multilayer using ITO and silver oxide (AgOx) as oxide and metal layers, respectively, is synthesized on a polymer substrate and used as an anode in highly flexible organic solar cells (OSCs). The 3D electrode is fabricated using vacuum sputtering sequences to achieve self-assembly of distinct ITO nanoparticles on a continuous ITO-AgOx-ITO multilayer at room-temperature without applying conventional high-temperature vapour-liquid-solid growth, solution-based nanoparticle coating, or complicated nanopatterning techniques. Since the 3D electrode enhances the hole-extraction rate in OSCs owing to its high surface area

Oligomer Molecules for Efficient Organic Photovoltaics.

PubMed

Lin, Yuze; Zhan, Xiaowei

2016-02-16

Solar cells, a renewable, clean energy technology that efficiently converts sunlight into electricity, are a promising long-term solution for energy and environmental problems caused by a mass of production and the use of fossil fuels. Solution-processed organic solar cells (OSCs) have attracted much attention in the past few years because of several advantages, including easy fabrication, low cost, lightweight, and flexibility. Now, OSCs exhibit power conversion efficiencies (PCEs) of over 10%. In the early stage of OSCs, vapor-deposited organic dye materials were first used in bilayer heterojunction devices in the 1980s, and then, solution-processed polymers were introduced in bulk heterojunction (BHJ) devices. Relative to polymers, vapor-deposited small molecules offer potential advantages, such as a defined molecular structure, definite molecular weight, easy purification, mass-scale production, and good batch-to-batch reproducibility. However, the limited solubility and high crystallinity of vapor-deposited small molecules are unfavorable for use in solution-processed BHJ OSCs. Conversely, polymers have good solution-processing and film-forming properties and are easily processed into flexible devices, whereas their polydispersity of molecular weights and difficulty in purification results in batch to batch variation, which may hamper performance reproducibility and commercialization. Oligomer molecules (OMs) are monodisperse big molecules with intermediate molecular weights (generally in the thousands), and their sizes are between those of small molecules (generally with molecular weights <1000) and polymers (generally with molecular weights >10000). OMs not only overcome shortcomings of both vapor-deposited small molecules and solution-processed polymers, but also combine their advantages, such as defined molecular structure, definite molecular weight, easy purification, mass-scale production, good batch-to-batch reproducibility, good solution processability

To what extent does the Health Professions Admission Test-Ireland predict performance in early undergraduate tests of communication and clinical skills? An observational cohort study.

PubMed

Kelly, Maureen E; Regan, Daniel; Dunne, Fidelma; Henn, Patrick; Newell, John; O'Flynn, Siun

2013-05-10

Internationally, tests of general mental ability are used in the selection of medical students. Examples include the Medical College Admission Test, Undergraduate Medicine and Health Sciences Admission Test and the UK Clinical Aptitude Test. The most widely used measure of their efficacy is predictive validity.A new tool, the Health Professions Admission Test- Ireland (HPAT-Ireland), was introduced in 2009. Traditionally, selection to Irish undergraduate medical schools relied on academic achievement. Since 2009, Irish and EU applicants are selected on a combination of their secondary school academic record (measured predominately by the Leaving Certificate Examination) and HPAT-Ireland score. This is the first study to report on the predictive validity of the HPAT-Ireland for early undergraduate assessments of communication and clinical skills. Students enrolled at two Irish medical schools in 2009 were followed up for two years. Data collected were gender, HPAT-Ireland total and subsection scores; Leaving Certificate Examination plus HPAT-Ireland combined score, Year 1 Objective Structured Clinical Examination (OSCE) scores (Total score, communication and clinical subtest scores), Year 1 Multiple Choice Questions and Year 2 OSCE and subset scores. We report descriptive statistics, Pearson correlation coefficients and Multiple linear regression models. Data were available for 312 students. In Year 1 none of the selection criteria were significantly related to student OSCE performance. The Leaving Certificate Examination and Leaving Certificate plus HPAT-Ireland combined scores correlated with MCQ marks.In Year 2 a series of significant correlations emerged between the HPAT-Ireland and subsections thereof with OSCE Communication Z-scores; OSCE Clinical Z-scores; and Total OSCE Z-scores. However on multiple regression only the relationship between Total OSCE Score and the Total HPAT-Ireland score remained significant; albeit the predictive power was modest. We found

To what extent does the Health Professions Admission Test-Ireland predict performance in early undergraduate tests of communication and clinical skills? – An observational cohort study

PubMed Central

2013-01-01

Background Internationally, tests of general mental ability are used in the selection of medical students. Examples include the Medical College Admission Test, Undergraduate Medicine and Health Sciences Admission Test and the UK Clinical Aptitude Test. The most widely used measure of their efficacy is predictive validity. A new tool, the Health Professions Admission Test- Ireland (HPAT-Ireland), was introduced in 2009. Traditionally, selection to Irish undergraduate medical schools relied on academic achievement. Since 2009, Irish and EU applicants are selected on a combination of their secondary school academic record (measured predominately by the Leaving Certificate Examination) and HPAT-Ireland score. This is the first study to report on the predictive validity of the HPAT-Ireland for early undergraduate assessments of communication and clinical skills. Method Students enrolled at two Irish medical schools in 2009 were followed up for two years. Data collected were gender, HPAT-Ireland total and subsection scores; Leaving Certificate Examination plus HPAT-Ireland combined score, Year 1 Objective Structured Clinical Examination (OSCE) scores (Total score, communication and clinical subtest scores), Year 1 Multiple Choice Questions and Year 2 OSCE and subset scores. We report descriptive statistics, Pearson correlation coefficients and Multiple linear regression models. Results Data were available for 312 students. In Year 1 none of the selection criteria were significantly related to student OSCE performance. The Leaving Certificate Examination and Leaving Certificate plus HPAT-Ireland combined scores correlated with MCQ marks. In Year 2 a series of significant correlations emerged between the HPAT-Ireland and subsections thereof with OSCE Communication Z-scores; OSCE Clinical Z-scores; and Total OSCE Z-scores. However on multiple regression only the relationship between Total OSCE Score and the Total HPAT-Ireland score remained significant; albeit the

Individual employee's perceptions of " Group-level Safety Climate" (supervisor referenced) versus " Organization-level Safety Climate" (top management referenced): Associations with safety outcomes for lone workers.

PubMed

Huang, Yueng-Hsiang; Lee, Jin; McFadden, Anna C; Rineer, Jennifer; Robertson, Michelle M

2017-01-01

Research has shown that safety climate is among the strongest predictors of safety behavior and safety outcomes in a variety of settings. Previous studies have established that safety climate is a multi-faceted construct referencing multiple levels of management within a company, most generally: the organization level (employee perceptions of top management's commitment to and prioritization of safety) and group level (employee perceptions of direct supervisor's commitment to and prioritization of safety). Yet, no research to date has examined the potential interaction between employees' organization-level safety climate (OSC) and group-level safety climate (GSC) perceptions. Furthermore, prior research has mainly focused on traditional work environments in which supervisors and workers interact in the same location throughout the day. Little research has been done to examine safety climate with regard to lone workers. The present study aims to address these gaps by examining the relationships between truck drivers' (as an example of lone workers) perceptions of OSC and GSC, both potential linear and non-linear relationships, and how these predict important safety outcomes. Participants were 8095 truck drivers from eight trucking companies in the United States with an average response rate of 44.8%. Results showed that employees' OSC and GSC perceptions are highly correlated (r= 0.78), but notable gaps between the two were observed for some truck drivers. Uniquely, both OSC and GSC scores were found to have curvilinear relationships with safe driving behavior, and both scores were equally predictive of safe driving behavior. Results also showed the two levels of climate significantly interacted with one another to predict safety behavior such that if either the OSC or GSC scores were low, the other's contribution to safety behavior became stronger. These findings suggest that OSC and GSC may function in a compensatory manner and promote safe driving behavior even

The validity and reliability of the sixth-year internal medical examination administered at the King Abdulaziz University Medical College.

PubMed

Fallatah, Hind I; Tekian, Ara; Park, Yoon Soo; Al Shawa, Lana

2015-02-01

Exams are essential components of medical students' knowledge and skill assessment during their clinical years of study. The paper provides a retrospective analysis of validity evidence for the internal medicine component of the written and clinical exams administered in 2012 and 2013 at King Abdulaziz University's Faculty of Medicine. Students' scores for the clinical and written exams were obtained. Four faculty members (two senior members and two junior members) were asked to rate the exam questions, including MCQs and OSCEs, for evidence of content validity using a rating scale of 1-5 for each item. Cronbach's alpha was used to measure the internal consistency reliability. Correlations were used to examine the associations between different forms of assessment and groups of students. A total of 824 students completed the internal medicine course and took the exam. The numbers of rated questions were 320 and 46 for the MCQ and OSCE, respectively. Significant correlations were found between the MCQ section, the OSCE section, and the continuous assessment marks, which include 20 long-case presentations during the course; participation in daily rounds, clinical sessions and tutorials; the performance of simple procedures, such as IV cannulation and ABG extraction; and the student log book. Although the OSCE exam was reliable for the two groups that had taken the final clinical OSCE, the clinical long- and short-case exams were not reliable across the two groups that had taken the oral clinical exams. The correlation analysis showed a significant linear association between the raters with respect to evidence of content validity for both the MCQ and OSCE, r = .219 P < .001 and r = .678 P < .001, respectively, and r = .241 P < .001 and r = .368 P = .023 for the internal structure validity, respectively. Reliability measured using Cronbach's alpha was greater for assessments administered in 2013. The pattern of relationships between the

Salvage plan & information sheet

DOT National Transportation Integrated Search

1997-11-05

This document allows the On Scene Coordinator (OSC) or Captain of the Port (COTP) to formulate and evaluate the impact of a Salvage Plan. Specifically, this document allows the OSC or COTP to: 1. Quickly gather all information needed during the respo...

High-Performance Long-Term-Stable Dopant-Free Perovskite Solar Cells and Additive-Free Organic Solar Cells by Employing Newly Designed Multirole π-Conjugated Polymers.

PubMed

Kranthiraja, Kakaraparthi; Gunasekar, Kumarasamy; Kim, Hyunji; Cho, An-Na; Park, Nam-Gyu; Kim, Seonha; Kim, Bumjoon J; Nishikubo, Ryosuke; Saeki, Akinori; Song, Myungkwan; Jin, Sung-Ho

2017-06-01

Perovskite solar cells (PSCs) and organic solar cells (OSCs) are promising renewable light-harvesting technologies with high performance, but the utilization of hazardous dopants and high boiling additives is harmful to all forms of life and the environment. Herein, new multirole π-conjugated polymers (P1-P3) are developed via a rational design approach through theoretical hindsight, further successfully subjecting them into dopant-free PSCs as hole-transporting materials and additive-free OSCs as photoactive donors, respectively. Especially, P3-based PSCs and OSCs not only show high power conversion efficiencies of 17.28% and 8.26%, but also display an excellent ambient stability up to 30 d (for PSCs only), owing to their inherent superior optoelectronic properties in their pristine form. Overall, the rational approach promises to support the development of environmentally and economically sustainable PSCs and OSCs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of the problem based learning-driven with the traditional didactic-lecture-based curricula.

PubMed

Zahid, Muhammad A; Varghese, Ramani; Mohammed, Ahmed M; Ayed, Adel K

2016-06-12

To compare the Problem-based learning (PBL) with the traditional lecture-based curricula. The single best answer Multiple Choice Questions (MCQ) and the Objective Structured Clinical Examination (OSCE) were used to compare performance of the lecture-based curriculum with the PBL medical student groups. The reliability for the MCQs and OSCE was calculated with Kuder-Richardson formula and Cronbach's alpha, respectively. The content validity of the MCQs and OSCE were tested by the Independent Subject Experts (ISE). The Student's t-test for independent samples was used to compare the item difficulty of the MCQs and OSCE's, and the Chi-square test was used to compare the grades between the two student groups. The PBL students outperformed the old curriculum students in overall grades, theoretical knowledge base (tested with K2 type MCQs) and OSCE. The number of the PBL students with scores between 80-90% (grade B) was significantly (p=0.035) higher while their number with scores between 60 to 69% (grade C) was significantly p=0.001) lower than the old curriculum students. Similarly, the mean MCQ and the OSCE scores of the new curriculum students were significantly higher (p = 0.001 and p = 0.025, respectively) than the old curriculum students. Lastly, the old curriculum students found the K2-MCQs to be more (p = 0.001) difficult than the single correct answer (K1 type) MCQs while no such difference was found by the new curriculum students. Suitably designed MCQs can be used to tap the higher cognitive knowledge base acquired in the PBL setting.

Multiple mini-interview as a predictor of performance in the objective structured clinical examination among Physician Associates in the United Kingdom: a cohort study

PubMed Central

Kumar, Narendra; Bhardwaj, Shailaja; Rahman, Eqram

2018-01-01

Introduction Patient satisfaction and health care outcomes are directly linked to useful communication skills. Therefore, excellent interpersonal skills are imperative for health care professionals. Multiple mini-interview (MMI) is designed as a selection tool to assess the communication skills of applicants in medical schools during the admission process. However, objective structured clinical examination (OSCE) assesses students’ communication and clinical skills at the end of their academic terms. Recently, Anglia Ruskin University, Chelmsford, UK, adopted MMI in the selection process for the first cohort of MSc Physician Associate trainees for the academic year 2015–2016. This study aimed to determine the likelihood of MMI as a predictor of future performance of communication skills in the OSCE. Materials and methods The anonymous data of the average scores of communication skills attained in MMI and OSCE at the end of year 1 were collected for 30 students from the Physician Associate program team. Subsequently, Pearson’s correlation was computed to determine the relationship between the average scores of communication skills attained in MMI, and OSCE during trimester 2 and trimester 3 by the Physician Associate trainees. Results The study showed positive correlation between the scores of communication skills attained in MMI and OSCE during trimester 2 (r=0.956, n=30, p<0.001) and trimester 3 (r=0.966, n=30, p<0.001). Conclusion The study provides empirical evidence for the validity of MMI as a predictor of future performance of Physician Associate trainees’ communication skills during subsequent OSCEs. PMID:29695944

HANDBOOK FOR OIL SPILL PROTECTION AND CLEANUP PRIORITIES

EPA Science Inventory

This handbook was developed in an easily accessible yet extensive field format for use by federally designated on-scene coordinators (OSC) to guide them in assessing priorities during all phases of an oil spill response. The guidelines presented will enable the OSC to (1) determi...

Implementation of an Electronic Objective Structured Clinical Exam for Assessing Practical Skills in Pre-Professional Physiotherapy and Occupational Therapy Programs: Examiner and Course Coordinator Perspectives

ERIC Educational Resources Information Center

Snodgrass, Suzanne J.; Ashby, Samantha E.; Rivett, Darren A.; Russell, Trevor

2014-01-01

Assessment of practical clinical skills is essential in the health fields. Objective Structured Clinical Exams (OSCEs), where examiners assess students performing clinical procedures on simulated patients (actors), are central to the evaluation of practical skills. However, traditional OSCEs require considerable time-investment to administer, and…

Summative Objective Structured Clinical Examination Assessment at the End of Anesthesia Residency for Perioperative Ultrasound.

PubMed

Mitchell, John D; Amir, Rabia; Montealegre-Gallegos, Mario; Mahmood, Feroze; Shnider, Marc; Mashari, Azad; Yeh, Lu; Bose, Ruma; Wong, Vanessa; Hess, Philip; Amador, Yannis; Jeganathan, Jelliffe; Jones, Stephanie B; Matyal, Robina

2018-06-01

While standardized examinations and data from simulators and phantom models can assess knowledge and manual skills for ultrasound, an Objective Structured Clinical Examination (OSCE) could assess workflow understanding. We recruited 8 experts to develop an OSCE to assess workflow understanding in perioperative ultrasound. The experts used a binary grading system to score 19 graduating anesthesia residents at 6 stations. Overall average performance was 86.2%, and 3 stations had an acceptable internal reliability (Kuder-Richardson formula 20 coefficient >0.5). After refinement, this OSCE can be combined with standardized examinations and data from simulators and phantom models to assess proficiency in ultrasound.

Purification of Oogonial Stem Cells From Adult Mouse and Human Ovaries: An Assessment of the Literature and a View Toward the Future

PubMed Central

Woods, Dori C.; White, Yvonne A. R.; Tilly, Jonathan L.

2013-01-01

Contemporary claims that mitotically active female germ line or oogonial stem cells (OSCs) exist and support oogenesis during postnatal life in mammals have been debated in the field of reproductive biology since March 2004, when a mouse study posed the first serious challenge to the dogma of a fixed pool of oocytes being endowed at birth in more than 50 years. Other studies have since been put forth that further question the validity of this dogma, including the isolation of OSCs from neonatal and adult mouse ovaries by 4 independent groups using multiple strategies. Two of these groups also reported that isolated mouse OSCs, once transplanted back into ovaries of adult female mice, differentiate into fully functional eggs that ovulate, fertilize, and produce healthy embryos and offspring. Arguably, one of the most significant advances in this emerging field was provided by a new research study published this year, which reported the successful isolation and functional characterization of OSCs from ovaries of reproductive age women. Two commentaries on this latest work, one cautiously supportive and one highly skeptical, were published soon afterward. This article evaluates the current literature regarding postnatal oogenesis in mammals and discusses important next steps for future work on OSC biology and function. PMID:23024060

Purification of oogonial stem cells from adult mouse and human ovaries: an assessment of the literature and a view toward the future.

PubMed

Woods, Dori C; White, Yvonne A R; Tilly, Jonathan L

2013-01-01

Contemporary claims that mitotically active female germ line or oogonial stem cells (OSCs) exist and support oogenesis during postnatal life in mammals have been debated in the field of reproductive biology since March 2004, when a mouse study posed the first serious challenge to the dogma of a fixed pool of oocytes being endowed at birth in more than 50 years. Other studies have since been put forth that further question the validity of this dogma, including the isolation of OSCs from neonatal and adult mouse ovaries by 4 independent groups using multiple strategies. Two of these groups also reported that isolated mouse OSCs, once transplanted back into ovaries of adult female mice, differentiate into fully functional eggs that ovulate, fertilize, and produce healthy embryos and offspring. Arguably, one of the most significant advances in this emerging field was provided by a new research study published this year, which reported the successful isolation and functional characterization of OSCs from ovaries of reproductive age women. Two commentaries on this latest work, one cautiously supportive and one highly skeptical, were published soon afterward. This article evaluates the current literature regarding postnatal oogenesis in mammals and discusses important next steps for future work on OSC biology and function.

Differentiation of Mouse Ovarian Stem Cells Toward Oocyte-Like Structure by Coculture with Granulosa Cells.

PubMed

Parvari, Soraya; Yazdekhasti, Hossein; Rajabi, Zahra; Gerayeli Malek, Valliollah; Rastegar, Tayebeh; Abbasi, Mehdi

2016-11-01

An increasing body of evidence has confirmed existence and function of ovarian stem cells (OSCs). In this study, a novel approach on differentiation of OSCs into oocyte-like cells (OLCs) has been addressed. Recently, different methods have been recruited to isolate and describe aspects of OSCs, but newer and more convenient strategies in isolation are still growing. Herein, a morphology-based method was used to isolate OSCs. Cell suspension of mouse neonatal ovaries was cultured and formed colonies were harvested mechanically and cultivated on mouse embryonic fibroblasts. For differentiation induction, colonies transferred on inactive granulosa cells. Results showed that cells in colonies were positive for alkaline phosphatase activity and reverse transcription-polymerase chain reaction (RT-PCR) confirmed the pluripotency characteristics of cells. Immunofluorescence revealed a positive signal for OCT4, DAZL, MVH, and SSEA1 in colonies as well. Results of RT-PCR and immunofluorescence confirmed that some OLCs were generated within the germ stem cell (GSCs) colonies. The applicability of morphological selection for isolation of GSCs was verified. This method is easier and more economic than other techniques. Our results demonstrate that granulosa cells were effective in inducing the differentiation of OSCs into OLCs through direct cell-to-cell contacts.

Semantic transparency in free stems: The effect of Orthography-Semantics Consistency on word recognition.

PubMed

Marelli, Marco; Amenta, Simona; Crepaldi, Davide

2015-01-01

A largely overlooked side effect in most studies of morphological priming is a consistent main effect of semantic transparency across priming conditions. That is, participants are faster at recognizing stems from transparent sets (e.g., farm) in comparison to stems from opaque sets (e.g., fruit), regardless of the preceding primes. This suggests that semantic transparency may also be consistently associated with some property of the stem word. We propose that this property might be traced back to the consistency, throughout the lexicon, between the orthographic form of a word and its meaning, here named Orthography-Semantics Consistency (OSC), and that an imbalance in OSC scores might explain the "stem transparency" effect. We exploited distributional semantic models to quantitatively characterize OSC, and tested its effect on visual word identification relying on large-scale data taken from the British Lexicon Project (BLP). Results indicated that (a) the "stem transparency" effect is solid and reliable, insofar as it holds in BLP lexical decision times (Experiment 1); (b) an imbalance in terms of OSC can account for it (Experiment 2); and (c) more generally, OSC explains variance in a large item sample from the BLP, proving to be an effective predictor in visual word access (Experiment 3).

Length of internship influences performance on medical residency exam.

PubMed

Santos, Itamar de Souza; Vieira, Joaquim Edson; Nunes, Maria do Patrocínio Tenório

2009-01-01

Medical education encompasses globally diverse context and conditions. The Brazilian scenario seemed a natural environment to study the influence of medical education programs and internship duration on the entrance exam for medical residency. This investigation evaluates some methods used during the entrance exam for medical residency as a means to make a distinction between candidates with longer clerkships. Candidates selected for a residency program performed a multiple-choice (MC), an open question (OQ) and OSCE-like tests, an interview and a curriculum analysis for participation in scientific meetings, papers published and voluntary activities. Groups were compared for gender, year of graduation, tests and OSCE scores. Participants were distributed into two groups based on clerkship duration: 2 years or less than 2 years. There was no difference for the MCT score among groups or any of the activities from interview and curriculum analysis. The 2 years clerkship group showed significantly higher OQ (p=0.009) and OSCE-like affective (p=0.025) and knowledge (p=0.002) scores. The OSCE test identified some aspects related to competence acquisition and assessed basic skills and attitudes essential to the supervised practice of medicine during residency. OSCE discriminated aspects not perceived by the sole use of knowledge tests.

Design of Donor Polymers with Strong Temperature-Dependent Aggregation Property for Efficient Organic Photovoltaics.

PubMed

Hu, Huawei; Chow, Philip C Y; Zhang, Guangye; Ma, Tingxuan; Liu, Jing; Yang, Guofang; Yan, He

2017-10-17

Bulk heterojunction (BHJ) organic solar cells (OSCs) have attracted intensive research attention over the past two decades owing to their unique advantages including mechanical flexibility, light weight, large area, and low-cost fabrications. To date, OSC devices have achieved power conversion efficiencies (PCEs) exceeding 12%. Much of the progress was enabled by the development of high-performance donor polymers with favorable morphological, electronic, and optical properties. A key problem in morphology control of OSCs is the trade-off between achieving small domain size and high polymer crystallinity, which is especially important for the realization of efficient thick-film devices with high fill factors. For example, the thickness of OSC blends containing state-of-the-art PTB7 family donor polymers are restricted to ∼100 nm due to their relatively low hole mobility and impure polymer domains. To further improve the device performance and promote commercialization of OSCs, there is a strong demand for the design of new donor polymers that can achieve an optimal blend morphology containing highly crystalline yet reasonably small domains. In this Account, we highlight recent progress on a new family of conjugated polymers with strong temperature-dependent aggregation (TDA) property. These polymers are mostly disaggregated and can be easily dissolved in solution at high temperatures, yet they can strongly aggregate when the solution is cooled to room temperature. This unique aggregation property allows us to control the disorder-order transition of the polymer during solution processing. By preheating the solution to high temperature (∼100 °C), the polymer chains are mostly disaggregated before spin coating; as the temperature of the solution drops during the spin coating process, the polymer can strongly aggregate and form crystalline domains yet that are not excessivelylarge. The overall blend morphology can be optimized by various processing conditions (e

Psychometric Structure of a Comprehensive Objective Structured Clinical Examination: A Factor Analytic Approach

ERIC Educational Resources Information Center

Volkan, Kevin; Simon, Steven R.; Baker, Harley; Todres, I. David

2004-01-01

Problem Statement and Background: While the psychometric properties of Objective Structured Clinical Examinations (OSCEs) have been studied, their latent structures have not been well characterized. This study examines a factor analytic model of a comprehensive OSCE and addresses implications for measurement of clinical performance. Methods: An…

75 FR 176 - Agency Information Collection Activities; Request for Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-04

... previously approved information collection consisting of a customer survey form. OSC is required by law to... the proper performance of OSC functions, including whether the information will have practical utility... to enhance the quality, utility, and clarity of the information to be collected; and (d) ways to...

Ternary solution-processed organic solar cells incorporating 2D materials

NASA Astrophysics Data System (ADS)

Stylianakis, Minas M.; Konios, Dimitrios; Petridis, Constantinos; Kakavelakis, George; Stratakis, Emmanuel; Kymakis, Emmanuel

2017-12-01

Recently, the study of ternary organic solar cells (OSCs) has attracted the efforts of the scientific community, leading to significantly higher performance due to the enhanced harvesting of incoming irradiation. Here, for the first time, and in order to promote this OSC architecture, we review the progress implemented by the application of two-dimensional (2D) materials in the field of blend bulk heterojunction ternary OSCs. Power conversion efficiency (PCE) improvements of the order of 40% compared to the reference binary devices, and PCEs in excess of 8% have been reported by incorporating graphene-based or other 2D materials as a third element inside the active layer. These OSCs combine the synergetic advantages of ternary devices and the superb properties of the 2D material family. In conclusion, the incorporation of the unique properties of graphene and other 2D materials inside the active layer opens up a very promising pathway in the design and construction of high-performance, simply fabricated and low- cost photovoltaic devices.

A Global Assessment of Dissolved Organic Carbon in Precipitation

NASA Astrophysics Data System (ADS)

Safieddine, Sarah A.; Heald, Colette L.

2017-11-01

Precipitation is the largest physical removal pathway of atmospheric reactive organic carbon in the form of dissolved organic carbon (DOC). We present the first global DOC distribution simulated with a global model. A total of 85 and 188 Tg C yr-1 are deposited to the ocean and the land, respectively, with DOC ranging between 0.1 and 10 mg C L-1 in this GEOS-Chem simulation. We compare the 2010 simulated DOC to a 30 year synthesis of measurements. Despite limited measurements and imperfect temporal matching, the model is able to reproduce much of the spatial variability of DOC (r = 0.63), with a low bias of 35%. We present the global average carbon oxidation state (OSc>¯) as a simple metric for describing the chemical composition. In the atmosphere, -1.8≤OSc>¯≤-0.6, and the increase in solubility upon oxidation leads to a global increase in OSc>¯ in precipitation with -0.6≤OSc>¯DOC≤0.

Cooptimization of Adhesion and Power Conversion Efficiency of Organic Solar Cells by Controlling Surface Energy of Buffer Layers.

PubMed

Lee, Inhwa; Noh, Jonghyeon; Lee, Jung-Yong; Kim, Taek-Soo

2017-10-25

Here, we demonstrate the cooptimization of the interfacial fracture energy and power conversion efficiency (PCE) of poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT)-based organic solar cells (OSCs) by surface treatments of the buffer layer. The investigated surface treatments of the buffer layer simultaneously changed the crack path and interfacial fracture energy of OSCs under mechanical stress and the work function of the buffer layer. To investigate the effects of surface treatments, the work of adhesion values were calculated and matched with the experimental results based on the Owens-Wendt model. Subsequently, we fabricated OSCs on surface-treated buffer layers. In particular, ZnO layers treated with poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) simultaneously satisfied the high mechanical reliability and PCE of OSCs by achieving high work of adhesion and optimized work function.

Nonlinear Phase Distortion in a Ti:Sapphire Optical Amplifier for Optical Stochastic Cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andorf, Matthew; Lebedev, Valeri; Piot, Philippe

2016-06-01

Optical Stochastic Cooling (OSC) has been considered for future high-luminosity colliders as it offers much faster cooling time in comparison to the micro-wave stochastic cooling. The OSC technique relies on collecting and amplifying a broadband optical signal from a pickup undulator and feeding the amplified signal back to the beam. It creates a corrective kick in a kicker undulator. Owing to its superb gain qualities and broadband amplification features, Titanium:Sapphire medium has been considered as a gain medium for the optical amplifier (OA) needed in the OSC*. A limiting factor for any OA used in OSC is the possibility ofmore » nonlinear phase distortions. In this paper we experimentally measure phase distortions by inserting a single-pass OA into one leg of a Mach-Zehnder interferometer. The measurement results are used to estimate the reduction of the corrective kick a particle would receive due to these phase distortions in the kicker undulator.« less

HATCN-based charge recombination layers as effective interconnectors for tandem organic solar cells.

PubMed

Wang, Rong-Bin; Wang, Qian-Kun; Xie, Hao-Jun; Xu, Lu-Hai; Duhm, Steffen; Li, Yan-Qing; Tang, Jian-Xin

2014-09-10

A comprehensive understanding of the energy-level alignment at the organic heterojunction interfaces is of paramount importance to optimize the performance of organic solar cells (OSCs). Here, the detailed electronic structures of organic interconnectors, consisting of cesium fluoride-doped 4,7-diphenyl-1,10-phenanthroline and hexaazatriphenylene-hexacarbonitrile (HATCN), have been investigated via in situ photoemission spectroscopy, and their impact on the charge recombination process in tandem OSCs has been identified. The experimental determination shows that the HATCN interlayer plays a significant role in the interface energetics with a dramatic decrease in the reverse built-in potential for electrons and holes from stacked subcells, which is beneficial to the charge recombination between HATCN and the adjacent layer. In accordance with the energy-level alignments, the open-circuit voltage of tandem OSC incorporating a HATCN-based interconnector is almost 2 times that of a single-cell OSC, revealing the effectiveness of the HATCN-based interconnectors in tandem organic devices.

Teaching core competencies of reconstructive microsurgery with the use of standardized patients.

PubMed

Son, Ji; Zeidler, Kamakshi R; Echo, Anthony; Otake, Leo; Ahdoot, Michael; Lee, Gordon K

2013-04-01

The Accreditation Council of Graduate Medical Education has defined 6 core competencies that residents must master before completing their training. Objective structured clinical examinations (OSCEs) using standardized patients are effective educational tools to assess and teach core competencies. We developed an OSCE specific for microsurgical head and neck reconstruction. Fifteen plastic surgery residents participated in the OSCE simulating a typical new patient consultation, which involved a patient with oral cancer. Residents were scored in all 6 core competencies by the standardized patients and faculty experts. Analysis of participant performance showed that although residents performed well overall, many lacked proficiency in systems-based practice. Junior residents were also more likely to omit critical elements of the physical examination compared to senior residents. We have modified our educational curriculum to specifically address these deficiencies. Our study demonstrates that the OSCE is an effective assessment tool for teaching and assessing all core competencies in microsurgery.

Large-area formation of self-aligned crystalline domains of organic semiconductors on transistor channels using CONNECT

PubMed Central

Park, Steve; Giri, Gaurav; Shaw, Leo; Pitner, Gregory; Ha, Jewook; Koo, Ja Hoon; Gu, Xiaodan; Park, Joonsuk; Lee, Tae Hoon; Nam, Ji Hyun; Hong, Yongtaek; Bao, Zhenan

2015-01-01

The electronic properties of solution-processable small-molecule organic semiconductors (OSCs) have rapidly improved in recent years, rendering them highly promising for various low-cost large-area electronic applications. However, practical applications of organic electronics require patterned and precisely registered OSC films within the transistor channel region with uniform electrical properties over a large area, a task that remains a significant challenge. Here, we present a technique termed “controlled OSC nucleation and extension for circuits” (CONNECT), which uses differential surface energy and solution shearing to simultaneously generate patterned and precisely registered OSC thin films within the channel region and with aligned crystalline domains, resulting in low device-to-device variability. We have fabricated transistor density as high as 840 dpi, with a yield of 99%. We have successfully built various logic gates and a 2-bit half-adder circuit, demonstrating the practical applicability of our technique for large-scale circuit fabrication. PMID:25902502

Evaluation of an Obstetric Ultrasound Curriculum for Midwives in Liberia.

PubMed

Bentley, Suzanne; Hexom, Braden; Nelson, Bret P

2015-09-01

Point-of-care ultrasound is an effective tool for clinical decision making in low- and middle-income countries, but lack of trained providers is a barrier to its utility in these settings. In Liberia, given that midwives provide most prenatal care, it is hypothesized that training them in prenatal ultrasound through an intensive condensed training course is both feasible and practical. This quantitative prospective study of preobservational and postobservational assessment evaluated a 1-week ultrasound curriculum consisting of 4 modules, each comprising a didactic component, a practical session, and supervised patient encounters. A knowledge-based pretest and presurvey addressing prior use and comfort were administered. At the intervention conclusion, identical posttests and postsurveys were administered with an objective structured clinical examination (OSCE). The test, survey, and OSCE were repeated after 1 year. All scores and responses were tabulated, and qualitative analysis with paired t tests was performed. Thirty-one midwives underwent intervention and written evaluation, with 14 followed up at 1 year. Seventeen underwent the OSCE, with 8 retained at 1 year. There was a significant increase between pretest and immediate and 1-year posttest scores (36.6% versus 90% and 66%; P < .001) but no difference between immediate and 1-year posttest scores (90% versus 66%; P > .05). Average overall comfort using ultrasound increased from presurvey to immediate postsurvey scores (from 1.8 to 3.8; P< .001) and remained higher at the 1-year postsurvey (1.8 to 3.4; P< .05). Overall OSCE scores remained high from immediately after the OSCE to 1 year after the OSCE (78% to 55%; P > .05). Midwives in Liberia had very low baseline knowledge and comfort using ultrasound. A 1-week curriculum increased both short- and long-term knowledge and comfort and led to adequate overall OSCE scores that were retained at 1 year. © 2015 by the American Institute of Ultrasound in Medicine.

Technical skills acquisition in surgery-bound senior medical students: an evaluation of student assertiveness.

PubMed

Talbott, Vanessa A; Marks, Joshua A; Bodzin, Adam S; Comeau, Jason A; Maxwell, Pinckney J; Isenberg, Gerald A; Martin, Niels D

2012-01-01

To prepare students pursuing surgical careers, we devised a senior subinternship curriculum supplement that focused on the acquisition of technical skills required of surgical residents. We hypothesized that more assertive students, those that accomplished more of the curriculum, would perform better on a technical skills Objective Structured Clinical Examination (OSCE). Senior medical students rotating on their first general surgery subinternship were administered a 6-station OSCE on the first day of their subinternship and again during the final week of the month-long rotation. A self-directed, 38-task "scavenger hunt" representing common intern level clinical skills, procedures, and patient care activities was provided to each student. The study was performed at Jefferson Medical College, a large, private medical school in Philadelphia, PA. Forty-nine senior students completed surgical subinternships between July 2009 and September 2010, and participated both in the pre-/post-OSCEs and the scavenger hunt. Students performed significantly better on the post-rotation OSCE than on the pre-rotation OSCE; 70.2% ± 8.1% vs. 60.4% ± 12.0%, p < 0.0001. Assertiveness scores from the "scavenger hunt" did not correlate with final OSCE scores (r = -0.328, p = 0.25), and were negatively correlated with the change between pre- and post-OSCE scores (r = -0.573, p < 0.04). Individual student assertiveness scores were determined by the number of tasks completed over the course of the rotation. As surgical education becomes more streamlined with evolving work hour restrictions, medical school education is playing an increasingly pivotal role in preparing students for internship. In our study, individual assertiveness in completing structured self-directed learning tasks did not directly predict the acquisition of proficiency in technical skills. We feel assertiveness is overshadowed by other factors that may carry more weight in terms of technical skills acquisition. Further

Communication Skills in Standardized-Patient Assessment of Final-Year Medical Students: A Psychometric Study

ERIC Educational Resources Information Center

Guiton, Gretchen; Hodgson, Carol S.; Delandshere, Ginett; Wilkerson, Luann

2004-01-01

The purpose of this study is to investigate the content-specificity of communication skills. It investigates the reliability and dimensionality of standardized patient (SP) ratings of communication skills in an Objective Structured Clinical Examination(OSCE) for final year medical students. An OSCE consisting of seven standardized patient(SP)…

75 FR 9003 - Agency Information Collection Activities; Request for Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-26

... a previously approved information collection consisting of a customer survey form. OSC is required... practical utility; (b) the accuracy of OSC's estimate of the burden of the proposed collections of information; (c) ways to enhance the quality, utility, and clarity of the information to be collected; and (d...

Increasing prevalence of emotional symptoms in higher socioeconomic strata: Trend study among Danish schoolchildren 1991-2014.

PubMed

Due, Pernille; Damsgaard, Mogens T; Madsen, Katrine R; Nielsen, Line; Rayce, Signe B; Holstein, Bjørn E

2018-01-01

The aims of this study were: (a) to examine trends in daily emotional symptoms among 11- to 15-year-olds from 1991 to 2014 in Denmark, and (b) to examine trends in social inequality in daily emotional symptoms, that is, whether the differences in prevalence between adolescents with parents of varying occupational social class changed over time. We combined seven comparable cross-sectional Health Behaviour in School-aged Children surveys ( N=31,169). Daily emotional symptoms were measured by the HBSC Symptom Check List and occupational social class (OSC) by students' reports about parents' occupation. We calculated absolute (per cent) differences in emotional symptoms between high and low OSC and relative differences by odds ratio for emotional symptoms by parents' OSC. Eight per cent reported at least one daily emotional symptoms, with an increasing trend from 1991 to 2014 ( p<0.001). The prevalence in high, middle and low OSC was 6.2%, 7.4% and 10.6% ( p<0.0001). From 1991 to 2014, there was an increase in the prevalence of daily emotional symptoms in high ( p<0.0001) and middle ( p<0.0001) but not low OSC ( p=0.4404). This resulted in a diminishing absolute social inequality in emotional symptoms. The statistical interaction between OSC and survey year was significant ( p=0.0023) and suggests a diminishing relative social inequality in emotional symptoms from 1991 to 2014. There was an increasing prevalence of daily emotional symptoms from 1991 to 2014 and a diminishing social inequality in prevalence of daily emotional symptoms in terms of both absolute and relative social inequality.

Self-regulated learning strategies used in surgical clerkship and the relationship with clinical achievement.

PubMed

Turan, Sevgi; Konan, Ali

2012-01-01

Self-regulated learning indicates students' skills in controlling their own learning. Self-regulated learning, which a context-specific process, emphasizes autonomy and control. Students gain more autonomy with respect to learning in the clinical years. Examining the self-regulated learning skills of students in this period will provide important clues about the level at which students are ready to use these skills in real-life conditions. The self-regulated learning strategies used by medical students in surgical clerkship were investigated in this study and their relation with clinical achievement was analyzed. The study was conducted during the surgery clerkship of medical students. The participation rate was 94% (309 students). Motivated Strategies for Learning Questionnaire (MSLQ), a case-based examination, Objective Structured Clinical Examination (OSCE), and tutor evaluations for assessing achievement were used. The relationship between the Motivated Strategies for Learning Questionnaire scores of the students and clinical achievement was analyzed with multilinear regression analysis. The findings showed that students use self-regulated learning skills at medium levels during their surgery clerkship. A relationship between these skills and OSCE scores and tutor evaluations was determined. OSCE scores of the students were observed to increase in conjunction with increased self-efficacy levels. However, as students' beliefs regarding control over learning increased, OSCE scores decreased. No significant relationship was defined between self-regulated learning skills and case-based examination scores. We observed that a greater self-efficacy for learning resulted in higher OSCE scores. Conversely, students who believe that learning is a result of their own effort had lower OSCE scores. Copyright © 2012 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Exploring personality dimensions that influence practice and performance of a simulated laparoscopic task in the objective structured clinical examination.

PubMed

Malhotra, Neha; Poolton, Jamie M; Wilson, Mark R; Leung, Gilberto; Zhu, Frank; Fan, Joe K M; Masters, Rich S W

2015-01-01

Surgical educators have encouraged the investigation of individual differences in aptitude and personality in surgical performance. An individual personality difference that has been shown to influence laparoscopic performance under time pressure is movement specific reinvestment. Movement specific reinvestment has 2 dimensions, movement self-consciousness (MS-C) (i.e., the propensity to consciously monitor movements) and conscious motor processing (CMP) (i.e., the propensity to consciously control movements), which have been shown to differentially influence laparoscopic performance in practice but have yet to be investigated in the context of psychological stress (e.g., the objective structured clinical examination [OSCE]). This study investigated the role of individual differences in propensity for MS-C and CMP in practice of a fundamental laparoscopic skill and in laparoscopic performance during the OSCE. Furthermore, this study examined whether individual differences during practice of a fundamental laparoscopic skill were predictive of laparoscopic performance during the OSCE. Overall, 77 final-year undergraduate medical students completed the movement specific reinvestment scale, an assessment tool that quantifies the propensity for MS-C and CMP. Participants were trained to proficiency on a fundamental laparoscopic skill. The number of trials to reach proficiency was measured, and completion times were recorded during early practice, later practice, and the OSCE. There was a trend for CMP to be negatively associated with the number of trials to reach proficiency (p = 0.064). A higher propensity for CMP was associated with fewer trials to reach proficiency (β = -0.70, p = 0.023). CMP and MS-C did not significantly predict completion times in the OSCE (p > 0.05). Completion times in early practice (β = 0.05, p = 0.016) and later practice (β = 0.47, p < 0.001) and number of trials to reach proficiency (β = 0.23, p = 0.003) significantly predicted

The GP tests of competence assessment: which part best predicts fitness to practise decisions?

PubMed

Jayaweera, Hirosha Keshani; Potts, Henry W W; Keshwani, Karim; Valerio, Chris; Baker, Magdalen; Mehdizadeh, Leila; Sturrock, Alison

2018-01-02

The General Medical Council (GMC) conducts Tests of Competence (ToC) for doctors referred for Fitness to Practise (FtP) issues. GPs take a single best answer knowledge test, an Objective Structured Clinical Examination (OSCE), and a Simulated Surgery (SimSurg) assessment which is a simulated GP consultation. The aim of this study was to examine the similarities between OSCEs and SimSurg to determine whether each assessment contributed something unique to GP ToCs. A mixed methods approach was used. Data were collated on 153 GPs who were required to undertake a ToC as a part of being investigated for FtP issues between February 2010 and October 2016. Using correlation analysis, we examined to what degree performance on the knowledge test, OSCE, and SimSurg related to case examiner recommendations and FtP outcomes, including the unique predictive power of these three assessments. The outcome measures were case examiner recommendations (i) not fit to practise; ii) fit to practise on a limited basis; or iii) fit to practise) as well as FtP outcomes (i) erased/removed from the register; ii) having restrictions/conditions; or iii) be in good standing). For the qualitative component, 45 GP assessors were asked to rate whether they assess the same competencies and which assessment provides better feedback about candidates. There was significant overlap between OSCEs and SimSurg, p < 0.001. SimSurg had additional predictive power in the presence of OSCEs and the knowledge test (p = 0.030) in distinguishing doctors from different FtP categories, while OSCEs did not (p = 0.080). Both the OSCEs (p = 0.004) and SimSurg (p < 0.001) had significant negative correlations with case examiner recommendations when accounting for the effects of the other two assessments. Inductive thematic analysis of the responses to the questionnaire showed that assessors perceived OSCEs to be better suited to target specific knowledge and skills. SimSurg was thought to produce a

32 CFR 516.71 - Duties.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-record, the Chief, DAJA-LE, will file necessary pleadings and make necessary appearances before the MSPB... appropriate DA personnel are fully apprised of their rights, duties and the nature and basis for an OSC... military members. (7) Ensure that personnel involved are advised of the nature and basis for an OSC...

Item Dependency in an Objective Structured Clinical Examination

ERIC Educational Resources Information Center

Iramaneerat, Cherdsak; Myford, Carol M.; Yudkowsky, Rachel

2006-01-01

An Objective Structured Clinical Examination (OSCE) is an assessment approach employed in medical education, in which residents rotate through multiple stations of standardized clinical tasks to evaluate their clinical competence. Because items used to evaluate residents' performance in each OSCE station are linked to the same task and are rated…

Adding Debriefing to Objective Structured Clinical Examinations to Enhance Disability Cultural Sensitivity in Pharmacy Students

ERIC Educational Resources Information Center

Smith, Mark Joseph

2016-01-01

Debriefing was added to the design of an objective structured clinical examination (OSCE) after second-year pharmacy students performed poorly at considering patient disability in planning for patient care. This mixed-methods study examines secondary data to explore whether and how the addition of a debriefing to an OSCE impacted pharmacy…

Randomized trial of teaching brief motivational interviewing to pediatric trainees to promote healthy behaviors in families.

PubMed

Lozano, Paula; McPhillips, Heather A; Hartzler, Bryan; Robertson, Andrea S; Runkle, Cecilia; Scholz, Kelley A; Stout, James W; Kieckhefer, Gail M

2010-06-01

That pediatric resident trainees would demonstrate increased counseling skill following training in brief motivational interviewing (MI). Randomized controlled trial. University of Washington Pediatric Residency. Pediatric residents (N = 18), including residents in postgraduate years 1, 2, 3, and 4. Collaborative Management in Pediatrics, a 9-hour behavior change curriculum based on brief MI plus written feedback on communication skills (based on a 3-month Objective Standardized Clinical Evaluation [OSCE]). The percentage of MI-consistent behavior (%MICO), a summary score for MI skill, was assessed via OSCEs in which standardized patients portray parents of children with asthma in 3 clinical scenarios (stations). The OSCEs were conducted at baseline and 3 and 7 months. Blinded coders rated videotaped OSCEs using a validated tool to tally communication behaviors. Training effects were assessed using linear regression controlling for baseline %MICO. Global ratings of counseling style served as secondary outcome measures. Trained residents demonstrated a trend toward increased skill (%MICO score) at 3 months compared with control residents. At 7 months, %MICO scores increased 16% to 20% (P < .02) across all OSCE stations after the combined intervention of Collaborative Management in Pediatrics training plus written feedback. The effect of training on global ratings supported the main findings. Pediatric trainees' skills in behavior change counseling improved following the combination of training in brief MI plus personalized feedback.

The objective structured clinical examination revisited for postgraduate trainees in general practice.

PubMed

Schoenmakers, Birgitte; Wens, Johan

2014-03-04

To investigate if the psychometric qualities of an OSCE consisting of more complex simulated patient encounters remain valid and reliable in the assessment of postgraduate trainees in general practice. In this intervention study without control group, the traditional OSCE was formally replaced by the new, complex version. The study population was composed by all postgraduate trainees (second and third phase) in general practice during the ongoing academic year. Data were handled and collected as part of the formal assessment program. Univariate analyses, the variance of scores and multivariate analyses were performed to assess the test qualities. A total of 340 students participated. Average final scores were slightly higher for third-phase students (t-test, p =0.05). Overall test scores were equally distributed on station level, circuit level and phase level. A multiple regression analysis revealed that test scores were dependent on the stations and circuits, but not on the master phase. In a changing learning environment, assessment and evaluation strategies require reorientation. The reliability and validity of the OSCE remain subject to discussion. In particular, when it comes to content and design, the traditional OSCE might underestimate the performance level of postgraduate trainees in general practice. A reshaping of this OSCE to a more sophisticated design with more complex patient encounters appears to restore the validity of the test results.

Evaluating the impact of a pre-rotation workshop on student preparation for clinical advanced pharmacy practice experiences.

PubMed

Medina, Melissa S; Stark, Jennifer E; Vesta, Kimi S; Lockhart, Staci M

2008-10-01

This pilot study was designed to evaluate the impact of a pre-rotation workshop (PRW) on pharmacy students' clinical skills and preparation for clinical Advanced Pharmacy Practice Experiences (APPE) involving direct patient care. Randomized controlled trial of an educational intervention with Institutional Review Board approval. PRW activities designed to simulate rotation activities around five competencies, patient charts, medication histories, SOAP notes, patient presentations, and professionalism. Endpoints were evaluated using clinical rotation preceptors' evaluation of performance and students' performance on objective structured clinical exams (OSCE). Eight fourth-year students and eight GPA matched controls (20% of the total class) were selected to voluntarily participate. The PRW demonstrated a positive impact on students' clinical skills and preparation for rotations by improving OSCE performance. However, no significant differences were found between groups when comparing preceptor evaluations of skills on rotations. These results are limited by the small sample size, potential OSCE "test-wiseness" effects, lack of OSCE evaluator blinding to study groups, potential case specificity effects due to the limited number of cases used on the OSCE and possible lack of sensitivity of the rotation evaluation tool to capture true differences among the experimental and control group participants. The PRW was successful at advancing students' clinical skills and preparation for rotations and may be considered as a tool to help bridge didactic to clinical experiences in the Pharm.D. curriculum.

Near-peer education: a novel teaching program.

PubMed

de Menezes, Sara; Premnath, Daphne

2016-05-30

This study aims to: 1) Evaluate whether a near-peer program improves perceived OSCE performance; 2) Identify factors motivating students to teach; 3) Evaluate role of near-peer teaching in medical education. A near-peer OSCE teaching program was implemented at Monash University's Peninsula Clinical School over the 2013 academic year. Forty 3rd-year and thirty final-year medical students were recruited as near-peer learners and educators, respectively. A post-program questionnaire was completed by learners prior to summative OSCEs (n=31), followed by post-OSCE focus groups (n=10). Near-peer teachers were interviewed at the program's conclusion (n=10). Qualitative data was analysed for emerging themes to assess the perceived value of the program. Learners felt peer-led teaching was more relevant to assessment, at an appropriate level of difficulty and delivered in a less threatening environment than other methods of teaching. They valued consistent practice and felt confident approaching their summative OSCEs. Educators enjoyed the opportunity to develop their teaching skills, citing mutual benefit and gratitude to past peer-educators as strong motivators to teach others. Near-peer education, valued by near-peer learners and teachers alike, was a useful method to improve preparation and perceived performance in summative examinations. In particular, a novel year-long, student-run initiative was regarded as a valuable and feasible adjunct to faculty teaching.

Agarose-gel electrophoresis for the quality assurance and purity of heparin formulations.

PubMed

Volpi, Nicola; Buzzega, Dania

2012-01-01

The adulteration of raw heparin (Hep) with a synthetic oversulfated chondroitin sulfate (OSCS) not found in nature produced in 2007-2008 a global crisis giving rise to the development of additional, new and specific methods for its quality assurance and purity. In this study, a simple and sensitive agarose-gel electrophoresis method has been developed for the visualization of OSCS in Hep samples along with other natural glycosaminoglycans possibly present as "process-related impurities", in particular dermatan sulfate (DS) and chondroitin sulfate (CS). Agarose-gel electrophoresis under non-conventional conditions is able to separate OSCS from Hep with its two components, the slow-moving and fast-moving species, DS and CS by performing separation for 15 h (overnight) and under high voltage (100 mA, ∼200 V). Densitometric scanning enabled us to calculate a limit of detection of ∼0.5 μg OSCS with a linear behaviour from 0.1 to 5 μg, comparable to CS/DS. Contaminated samples from Hep manufacturers were analyzed and quantitative data were found comparable to previous studies. Due to its capacity to process many samples in a single run and to the equipment commonly available in laboratories, this analytical method would be suitable for the identification and quantification of contamination by other polysaccharides, in particular OSCS and DS, within Hep preparations and formulations. Copyright © 2012 Elsevier B.V. All rights reserved.

Surpassing 10% Efficiency Benchmark for Nonfullerene Organic Solar Cells by Scalable Coating in Air from Single Nonhalogenated Solvent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Long; Xiong, Yuan; Zhang, Qianqian

The commercialization of nonfullerene organic solar cells (OSCs) relies critically on the response under typical operating conditions (for instance, temperature, humidity) and the ability of scale-up. Despite the rapid increase in power conversion efficiency (PCE) of spin-coated devices fabricated in a protective atmosphere, the device efficiencies of printed nonfullerene OSC devices by blade-coating are still lower than 6%. This slow progress significantly limits the practical printing of high-performance nonfullerene OSCs. Here, a new and stable nonfullerene combination was introduced by pairing a commercially available nonfluorinated acceptor IT-M with the polymeric donor FTAZ. Over 12%-efficiency can be achieved in spincoated FTAZ:IT-Mmore » devices using a single halogen-free solvent. More importantly, chlorinefree, in air blade-coating of FTAZ:IT-M is able to yield a PCE of nearly 11%, despite a humidity of ~50%. X-ray scattering results reveal that large π-π coherence lengths, high degree of faceon orientation with respect to the substrate, and small domain spacings of ~20 nm are closely correlated with such high device performance. Our material system and approach yields the highest reported performance for nonfullerene OSC devices by a coating technique approximating scalable fabrication methods and holds great promise for the development of low-cost, low-toxicity, and high-efficiency OSCs by high-throughput production.« less

Effects of Various Calcium Powders as Replacers for Synthetic Phosphate on the Quality Properties of Ground Pork Meat Products

PubMed Central

2017-01-01

The aim of this study was to identify the optimal and superior type of natural calcium for replacing phosphate in cooked ground pork products. To achieve this, 0.5% eggshell calcium (ESC), oyster shell calcium (OSC), marine algae calcium (MAC), or milk calcium (MC) was added to ground pork meat products. The effect of this substitution was studied by comparing the substituted products with products containing 0.3% phosphate blend (control). ESC was considered an ideal phosphate replacer for minimizing the cooking loss, which likely resulted from the increase in the pH of the product. Among the other natural calcium types, OSC treatment did not cause a significant increase in pH, but it lowered the cooking loss. CIE L* values were higher (p<0.05) in products treated with OSC or MC than the control, and lowest (p<0.05) in the products with ESC. However, products with ESC had higher (p<0.05) CIE a* and CIE b* values than the control and products treated with other powders. Compared to the control, products treated with ESC and OSC had similar substitution effects on the textural properties of the products. Therefore, the results of this study suggested that the combined use of ESC and OSC could be a potentially effective method for replacing synthetic phosphate in ground pork products. PMID:28747832

Coupled thermal, electrical, and fluid flow analyses of AMTEC multitube cell with adiabatic side wall

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schock, A.; Or, C.; Noravian, H.

1997-01-01

The paper describes a novel OSC-generated methodology for analyzing the performance of multitube AMTEC (Alkali Metal Thermal-to-Electrical Conversion) cells, which are under development by AMPS (Advanced Modular Power Systems, Inc.) for the Air Force Phillips Laboratory (AFPL) and NASA{close_quote}s Jet Propulsion Laboratory (JPL), for possible application to the Pluto Express and other space missions. The OSC study was supported by the Department of Energy (DOE), and was strongly encouraged by JPL, AFPL, and AMPS. It resulted in an iterative procedure for the coupled solution of the interdependent thermal, electrical, and fluid flow differential and integral equations governing the performance ofmore » AMTEC cells and generators. The paper clarifies the OSC procedure by presenting detailed results of its application to an illustrative example of a converter cell with an adiabatic side wall, including the non-linear axial variation of temperature, pressure, open-circuit voltage, interelectrode voltage, current density, axial current, sodium mass flow, and power density. The next paper in these proceedings describes parametric results obtained by applying the same procedure to variations of the baseline adiabatic converter design, culminating in an OSC-recommended revised cell design. A subsequent paper in these proceedings extends the procedure to analyze a variety of OSC-designed radioisotope-heated generators employing non-adiabatic multitube AMTEC cells. {copyright} {ital 1997 American Institute of Physics.}« less

Assessment of Benefits and Costs of Out of School Care: Insight.

ERIC Educational Resources Information Center

Scottish Executive Education Dept., Edinburgh.

A pivotal part of Scotland's Childcare Strategy is the provision of out-of-school care (OSC). The Scottish Executive Education Department commissioned an assessment of the costs and benefits of OSC in Scotland. Despite methodological issues such as lack of longitudinal studies, the review of existing literature evidenced a range of economic…

Does an Advanced Pelvic Simulation Curriculum Improve Resident Performance on a Pediatric and Adolescent Gynecology Focused Objective Structured Clinical Examination? A Cohort Study.

PubMed

Dumont, Tania; Hakim, Julie; Black, Amanda; Fleming, Nathalie

2016-06-01

To determine the effect of an advanced pelvic simulation curriculum on resident performance on a pediatric and adolescent gynecology (PAG) focused objective structured clinical examination (OSCE). Obstetrics and gynecology residents in a single academic Canadian center participated in a PAG simulation curriculum. An OSCE on prepubertal vaginal bleeding was administered at the biannual OSCE examination 2 months before the simulation curriculum and again 3 months after the simulation curriculum. Academic half-day at the University of Ottawa Skills and Simulation Centre. Obstetrics and gynecology residents from the University of Ottawa. Participants completed 4 stations teaching PAG-appropriate history-taking, genital examination, Tanner staging, vaginal sampling and flushing, hymenectomy, vaginoscopy, laparoscopic adnexal detorsion, and approach to the child and/or adolescent. Advanced pelvic models were used for procedure-specific stations. The primary outcome measure was change in mean score on a prepubertal vaginal bleeding OSCE station. Secondary outcome measures were changes in individual component scores. Fourteen residents completed the simulation curriculum and the PAG OSCE at the 2 separate time points (before and after simulation curriculum). The mean OSCE score before the simulation curriculum was 54.6% (20.5 of 37) and mean score after the curriculum was 78.1% (28.9 of 37; P < .001). Significant score increases were found in history-taking, examination, differential diagnosis, identification of organism, surgical procedures, and identification of foreign body (P < .01 for all). This innovative PAG simulation curriculum significantly increased residents' knowledge in PAG history-taking, examination skills, operative procedures, and approach to the child and/or adolescent. Obstetrics and Gynecology Program Directors should consider incorporating PAG simulation training into their curriculum to ensure that residents meet their learning objectives and

Outbreak of Adverse Reactions Associated with Contaminated Heparin

PubMed Central

Blossom, David B.; Kallen, Alexander J.; Patel, Priti R.; Elward, Alexis; Robinson, Luke; Gao, Ganpan; Langer, Robert; Perkins, Kiran M.; Jaeger, Jennifer L.; Kurkjian, Katie M.; Jones, Marilyn; Schillie, Sarah F.; Shehab, Nadine; Ketterer, Daniel; Venkataraman, Ganesh; Kishimoto, Takashi Kei; Shriver, Zachary; McMahon, Ann W.; Austen, K. Frank; Kozlowski, Steven; Srinivasan, Arjun; Turabelidze, George; Gould, Carolyn V.; Arduino, Matthew J.; Sasisekharan, Ram

2013-01-01

BACKGROUND In January 2008, the Centers for Disease Control and Prevention began a nationwide investigation of severe adverse reactions that were first detected in a single hemodialysis facility. Preliminary findings suggested that heparin was a possible cause of the reactions. METHODS Information on clinical manifestations and on exposure was collected for patients who had signs and symptoms that were consistent with an allergic-type reaction after November 1, 2007. Twenty-one dialysis facilities that reported reactions and 23 facilities that reported no reactions were included in a case–control study to identify facility-level risk factors. Unopened heparin vials from facilities that reported reactions were tested for contaminants. RESULTS A total of 152 adverse reactions associated with heparin were identified in 113 patients from 13 states from November 19, 2007, through January 31, 2008. The use of heparin manufactured by Baxter Healthcare was the factor most strongly associated with reactions (present in 100.0% of case facilities vs. 4.3% of control facilities, P<0.001). Vials of heparin manufactured by Baxter from facilities that reported reactions contained a contaminant identified as oversulfated chondroitin sulfate (OSCS). Adverse reactions to the OSCS-contaminated heparin were often characterized by hypotension, nausea, and shortness of breath occurring within 30 minutes after administration. Of 130 reactions for which information on the heparin lot was available, 128 (98.5%) occurred in a facility that had OSCS-contaminated heparin on the premises. Of 54 reactions for which the lot number of administered heparin was known, 52 (96.3%) occurred after the administration of OSCS-contaminated heparin. CONCLUSIONS Heparin contaminated with OSCS was epidemiologically linked to adverse reactions in this nationwide outbreak. The reported clinical features of many of the cases further support the conclusion that contamination of heparin with OSCS was the cause

Using Simulation in Assessment and Teaching: OSCE Adapted for Social Work

ERIC Educational Resources Information Center

Bogo, Marion; Rawlings, Mary; Katz, Ellen; Logie, Carmen

2014-01-01

This detailed book by the most experienced authors in the field describes how to develop and implement the objective structured clinical examination (OSCE) for social work education. In addition to a wealth of practical material in the appendices, two videos produced especially for this book (accessible online) show the OSCE process step-by-step.…

Organic and perovskite solar cells: Working principles, materials and interfaces.

PubMed

Marinova, Nevena; Valero, Silvia; Delgado, Juan Luis

2017-02-15

In the last decades organic solar cells (OSCs) have been considered as a promising photovoltaic technology with the potential to provide reasonable power conversion efficiencies combined with low cost and easy processability. Unexpectedly, Perovskite Solar Cells (PSCs) have experienced unprecedented rise in Power Conversion Efficiency (PCE) thus emerging as a highly efficient photovoltaic technology. OSCs and PSCs are two different kind of devices with distinct charge generation mechanism, which however share some similarities in the materials processing, thus standard strategies developed for OSCs are currently being employed in PSCs. In this article, we recapitulate the main processes in these two types of photovoltaic technologies with an emphasis on interfacial processes and interfacial modification, spotlighting the materials and newest approaches in the interfacial engineering. We discuss on the relevance of well-known materials coming from the OSCs field, which are now being tested in the PSCs field, while maintaining a focus on the importance of the material design for highly efficient, stable and accessible solar cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Mixing-Induced Anisotropic Correlations in Molecular Crystalline Systems: Rationalizing the Behavior of Organic Semiconductor Blends

NASA Astrophysics Data System (ADS)

Broch, Katharina; Aufderheide, Antje; Novak, Jiri; Hinderhofer, Alexander; Gerlach, Alexander; Banerjee, Rupak; Schreiber, Frank

2013-03-01

Binary mixtures of organic semiconductors (OSCs) have recently become an important field of research, as they find applications in opto-electronic devices. In these systems, the mixing (intermixing vs. phase separation) and ordering behavior is crucial, since it affects the optical and electronic properties. We present a comprehensive study of binary mixtures of the three prototypical OSCs pentacene (PEN), perfluoropentacene (PFP) and diindenoperlyene (DIP) in all possible combinations. Using X-ray reflectivity and grazing incidence X-ray diffraction we investigate the stuctural properties of the mixed films as well as their impact on the optical spectra obtained by spectroscopic ellipsometry. For PEN:DIP we find an anisotropic ordering behavior, comparable to that observed in some liquid crystals, which is fundamentally new for OSCs. The influence of sterical compatibility and the strength of the intermolecular interactions on the mixing and ordering behavior in the different blends will be discussed by extending a conventional mean-field model. Finally, we discuss general rules for the targeted preparation of blends of OSCs.

Outcomes of Individualized Formative Assessments in a Pharmacy Skills Laboratory.

PubMed

Gums, Tyler Harris; Kleppinger, Erika L; Urick, Benjamin Y

2014-11-15

To determine the effectiveness of an individualized teaching method in a pharmacy skills laboratory. All third-year students enrolled in an Accreditation Council for Pharmacy Education (ACPE) accredited doctor of pharmacy program (n=150) received an individual formative assessment from clinical pharmacists on communication skills and clinical competency after the students counseled standardized mock glaucoma patients during a laboratory focused on alternative dosing formulations. Objective structured clinical examination (OSCE) scores for this station from the 2012 and 2013 classes were compared before and after the intervention. Ophthalmic OSCE station scores were higher after the individual formative feedback intervention. Students in 2013 had a mean score of 83.2 ± 8.3% compared to a mean of 74.3 ± 12.9% in 2012 for this OSCE station. The percentage of students receiving an "A" on the OSCE station increased from 8.1% to 31.3% after the intervention. Individualized formative teaching methods benefited students in both their communication skills and clinical assessment. Future research should focus on wider implementation and overcoming obstacles, such as increased facilitator needs.

Tin doped indium oxide anodes with artificially controlled nano-scale roughness using segregated Ag nanoparticles for organic solar cells

NASA Astrophysics Data System (ADS)

Kim, Hyo-Joong; Ko, Eun-Hye; Noh, Yong-Jin; Na, Seok-In; Kim, Han-Ki

2016-09-01

Nano-scale surface roughness in transparent ITO films was artificially formed by sputtering a mixed Ag and ITO layer and wet etching of segregated Ag nanoparticles from the surface of the ITO film. Effective removal of self-segregated Ag particles from the grain boundaries and surface of the crystalline ITO film led to a change in only the nano-scale surface morphology of ITO film without changes in the sheet resistance and optical transmittance. A nano-scale rough surface of the ITO film led to an increase in contact area between the hole transport layer and the ITO anode, and eventually increased the hole extraction efficiency in the organic solar cells (OSCs). The heterojunction OSCs fabricated on the ITO anode with a nano-scale surface roughness exhibited a higher power conversion efficiency of 3.320%, than that (2.938%) of OSCs made with the reference ITO/glass. The results here introduce a new method to improve the performance of OSCs by simply modifying the surface morphology of the ITO anodes.

EPA's On-Scene Coordinators (OSCs)

EPA Pesticide Factsheets

These are the federal officials responsible for monitoring or directing responses to all oil spills and hazardous substance releases reported to the government. They are responsible for assessment, monitoring, response assistance, and evaluation.

ROC and Loss Function Analysis in Sequential Testing

ERIC Educational Resources Information Center

Muijtjens, Arno M. M.; Van Luijk, Scheltus J.; Van Der Vleuten, Cees P. M.

2006-01-01

Sequential testing is applied to reduce costs in SP-based tests (OSCEs). Initially, all candidates take a screening test consisting of a part of the OSCE. Candidates who fail the screen sit the complete test, whereas those who pass the screen are qualified as a pass of the complete test. The procedure may result in a reduction of testing…

Microstructural studies of organic spin valves and superconducting vortex ratchets

NASA Astrophysics Data System (ADS)

Liu, Yaohua

Thin film's microstructure plays important roles in their transport properties. Spin transport in organic semiconductors (OSCs) were studied using spin valves structures, with Fe and Co as the top and bottom ferromagnetic (FM) contacts, respectively. Magnetoresistance (MR) effects have been observed up to room temperature in junctions based on an electron-carrying OSC, tris(8-hyroxyquinoline) aluminum (Alq3) and a hole-carrying OSC, copper phthalocyanine (CuPc). However, junctions based on two other electron-carrying OSCs with higher lateral mobilities showed weaker spin transport effects. Morphological studies indicated that these high mobility films had rougher surfaces than either Alq3 or CuPc, therefore the degradation may originate from enhanced scattering due to the rougher FM/OSC interfaces. FM/OSC interfaces were studied in detail in Alga-based devices. These multilayer films have well-defined layer structures with modest average chemical roughness (3-5 nm) at the FM/A1q3 interfaces. Reflectometry shows that larger MR effects are correlated with sharper FM/OSC interfaces and a magnetically dead layer at the Alq3/Fe boundary. Combined with magnetotransport and magnetometery studies, our results support spin injection and transport in Alq3. A lower bound for the spin diffusion length in Alq3 was estimated as 43 +/- 5 nm at 80 K. However, the subtle correlations between microstructure and magnetotransport indicate the importance of interfacial effects. Thin film's microstructures can also be engineered to study interesting physics phenomena. We studied superconducting vortex motion, especially the vortex ratchet effect, in one-dimensional thickness-modulated granular Al films. The potential profile for a single vortex due to thickness modulation was estimated using the Bardeen-Stephen model, which agrees with the transport results. For a sample with a nearly sawtooth potential profile, the rectification velocity showed a maximum around 4.4B1, where B1 is the

Objective, domain-specific HER2 measurement in uterine and ovarian serous carcinomas and its clinical significance.

PubMed

Carvajal-Hausdorf, Daniel E; Schalper, Kurt A; Bai, Yalai; Black, Jonathan; Santin, Alessandro D; Rimm, David L

2017-04-01

HER2 overexpression/amplification is identified in up to 40% of uterine serous carcinomas (USC) and 10% of ovarian serous carcinomas (OSC). However, clinical trials using various HER2-targeted agents failed to show significant responses. FDA-approved HER2 assays target only the protein's intracellular domain (ICD) and not the extracellular domain (ECD). Previous quantitative studies in breast cancer by our group have shown that ICD of HER2 is expressed in some cases that do not express the HER2 ECD. We measured HER2 ICD and ECD in USC and OSC samples, and determined their relationship with clinico-pathologic characteristics and survival. We measured HER2 ICD and ECD levels in 2 cohorts of USC and OSC comprising 102 and 175 patients, respectively. HER2 antibodies targeting ICD (CB11) and ECD (SP3) were validated and standardized using the AQUA® method of quantitative immunofluorescence (QIF) and a previously reported HER2 standardization tissue microarray (TMA). Objective, population-based cut-points were used to stratify patients according to HER2 ICD/ECD status. In USC, 8% of patients with high HER2 ICD had low ECD levels (6/75 patients). In OSC, 42% of patients with high HER2 ICD had low ECD levels (29/69 patients). HER2 ICD/ECD status in USC and OSC was not significantly associated with major clinico-pathological features or survival. Using objective, domain-specific HER2 measurement, 8% of USC and 42% of OSC patients with high HER2 ICD levels do not show uniform overexpression of the ECD. This may be related to the presence of p95 HER2, an oncogenic fragment generated by full protein cleavage or alternative initiation of translation. These observations raise the possibility that USC/OSCs expressing low ECD despite being HER2-positive by ICD measurement, may benefit from therapies directed against the intracellular domain (e.g. lapatinib or afatinib) alone or in combination with extracellular domain-directed drugs (e.g. trastuzumab, pertuzumab, T-DM1

Reliability analysis of the objective structured clinical examination using generalizability theory.

PubMed

Trejo-Mejía, Juan Andrés; Sánchez-Mendiola, Melchor; Méndez-Ramírez, Ignacio; Martínez-González, Adrián

2016-01-01

The objective structured clinical examination (OSCE) is a widely used method for assessing clinical competence in health sciences education. Studies using this method have shown evidence of validity and reliability. There are no published studies of OSCE reliability measurement with generalizability theory (G-theory) in Latin America. The aims of this study were to assess the reliability of an OSCE in medical students using G-theory and explore its usefulness for quality improvement. An observational cross-sectional study was conducted at National Autonomous University of Mexico (UNAM) Faculty of Medicine in Mexico City. A total of 278 fifth-year medical students were assessed with an 18-station OSCE in a summative end-of-career final examination. There were four exam versions. G-theory with a crossover random effects design was used to identify the main sources of variance. Examiners, standardized patients, and cases were considered as a single facet of analysis. The exam was applied to 278 medical students. The OSCE had a generalizability coefficient of 0.93. The major components of variance were stations, students, and residual error. The sites and the versions of the tests had minimum variance. Our study achieved a G coefficient similar to that found in other reports, which is acceptable for summative tests. G-theory allows the estimation of the magnitude of multiple sources of error and helps decision makers to determine the number of stations, test versions, and examiners needed to obtain reliable measurements.

Near-peer education: a novel teaching program

PubMed Central

Premnath, Daphne

2016-01-01

Objectives This study aims to: 1) Evaluate whether a near-peer program improves perceived OSCE performance; 2) Identify factors motivating students to teach; 3) Evaluate role of near-peer teaching in medical education. Methods A near-peer OSCE teaching program was implemented at Monash University’s Peninsula Clinical School over the 2013 academic year. Forty 3rd-year and thirty final-year medical students were recruited as near-peer learners and educators, respectively. A post-program questionnaire was completed by learners prior to summative OSCEs (n=31), followed by post-OSCE focus groups (n=10). Near-peer teachers were interviewed at the program’s conclusion (n=10). Qualitative data was analysed for emerging themes to assess the perceived value of the program. Results Learners felt peer-led teaching was more relevant to assessment, at an appropriate level of difficulty and delivered in a less threatening environment than other methods of teaching. They valued consistent practice and felt confident approaching their summative OSCEs. Educators enjoyed the opportunity to develop their teaching skills, citing mutual benefit and gratitude to past peer-educators as strong motivators to teach others. Conclusions Near-peer education, valued by near-peer learners and teachers alike, was a useful method to improve preparation and perceived performance in summative examinations. In particular, a novel year-long, student-run initiative was regarded as a valuable and feasible adjunct to faculty teaching. PMID:27239951

An Unfused-Core-Based Nonfullerene Acceptor Enables High-Efficiency Organic Solar Cells with Excellent Morphological Stability at High Temperatures.

PubMed

Li, Shuixing; Zhan, Lingling; Liu, Feng; Ren, Jie; Shi, Minmin; Li, Chang-Zhi; Russell, Thomas P; Chen, Hongzheng

2018-02-01

Most nonfullerene acceptors developed so far for high-performance organic solar cells (OSCs) are designed in planar molecular geometry containing a fused-ring core. In this work, a new nonfullerene acceptor of DF-PCIC is synthesized with an unfused-ring core containing two cyclopentadithiophene (CPDT) moieties and one 2,5-difluorobenzene (DFB) group. A nearly planar geometry is realized through the F···H noncovalent interaction between CPDT and DFB for DF-PCIC. After proper optimizations, the OSCs with DF-PCIC as the acceptor and the polymer PBDB-T as the donor yield the best power conversion efficiency (PCE) of 10.14% with a high fill factor of 0.72. To the best of our knowledge, this efficiency is among the highest values for the OSCs with nonfullerene acceptors owning unfused-ring cores. Furthermore, no obvious morphological changes are observed for the thermally treated PBDB-T:DF-PCIC blended films, and the relevant devices can keep ≈70% of the original PCEs upon thermal treatment at 180 °C for 12 h. This tolerance of such a high temperature for so long time is rarely reported for fullerene-free OSCs, which might be due to the unique unfused-ring core of DF-PCIC. Therefore, the work provides new idea for the design of new nonfullerene acceptors applicable in commercial OSCs in the future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly sensitive ratiometric detection of heparin and its oversulfated chondroitin sulfate contaminant by fluorescent peptidyl probe.

PubMed

Mehta, Pramod Kumar; Lee, Hyeri; Lee, Keun-Hyeung

2017-05-15

The selective and sensitive detection of heparin, an anticoagulant in clinics as well as its contaminant oversulfated chondroitin sulfate (OSCS) is of great importance. We first reported a ratiometric sensing method for heparin as well as OSCS contaminants in heparin using a fluorescent peptidyl probe (Pep1, pyrene-GSRKR) and heparin-digestive enzyme. Pep1 exhibited a highly sensitive ratiometric response to nanomolar concentration of heparin in aqueous solution over a wide pH range (2~11) and showed highly selective ratiometric response to heparin among biological competitors such as hyaluronic acid and chondroitin sulfate. Pep1 showed a linear ratiometric response to nanomolar concentrations of heparin in aqueous solutions and in human serum samples. The detection limit for heparin was calculated to be 2.46nM (R 2 =0.99) in aqueous solutions, 2.98nM (R 2 =0.98) in 1% serum samples, and 3.43nM (R 2 =0.99) in 5% serum samples. Pep1 was applied to detect the contaminated OSCS in heparin with heparinase I, II, and III, respectively. The ratiometric sensing method using Pep1 and heparinase II was highly sensitive, fast, and efficient for the detection of OSCS contaminant in heparin. Pep1 with heparinase II could detect as low as 0.0001% (w/w) of OSCS in heparin by a ratiometric response. Copyright © 2017 Elsevier B.V. All rights reserved.

Reliability analysis of the objective structured clinical examination using generalizability theory.

PubMed

Trejo-Mejía, Juan Andrés; Sánchez-Mendiola, Melchor; Méndez-Ramírez, Ignacio; Martínez-González, Adrián

2016-01-01

Background The objective structured clinical examination (OSCE) is a widely used method for assessing clinical competence in health sciences education. Studies using this method have shown evidence of validity and reliability. There are no published studies of OSCE reliability measurement with generalizability theory (G-theory) in Latin America. The aims of this study were to assess the reliability of an OSCE in medical students using G-theory and explore its usefulness for quality improvement. Methods An observational cross-sectional study was conducted at National Autonomous University of Mexico (UNAM) Faculty of Medicine in Mexico City. A total of 278 fifth-year medical students were assessed with an 18-station OSCE in a summative end-of-career final examination. There were four exam versions. G-theory with a crossover random effects design was used to identify the main sources of variance. Examiners, standardized patients, and cases were considered as a single facet of analysis. Results The exam was applied to 278 medical students. The OSCE had a generalizability coefficient of 0.93. The major components of variance were stations, students, and residual error. The sites and the versions of the tests had minimum variance. Conclusions Our study achieved a G coefficient similar to that found in other reports, which is acceptable for summative tests. G-theory allows the estimation of the magnitude of multiple sources of error and helps decision makers to determine the number of stations, test versions, and examiners needed to obtain reliable measurements.

Excitation of H+2 with one-cycle laser pulses: shaped post-laser-field electronic oscillations, generation of higher- and lower-order harmonics

NASA Astrophysics Data System (ADS)

Paramonov, Guennaddi K.; Kühn, Oliver; Bandrauk, André D.

2017-08-01

Non-Born-Oppenheimer quantum dynamics of H+2 excited by shaped one-cycle laser pulses linearly polarised along the molecular axis have been studied by the numerical solution of the time-dependent Schrödinger equation within a three-dimensional model, including the internuclear separation, R, and the electron coordinates z and ρ. Laser carrier frequencies corresponding to the wavelengths λl = 25 nm through λl = 400 nm were used and the amplitudes of the pulses were chosen such that the energy of H+2 was close to its dissociation threshold at the end of any laser pulse applied. It is shown that there exists a characteristic oscillation frequency ωosc ≃ 0.2265 au (corresponding to the period of τosc ≃ 0.671 fs and the wavelength of λosc ≃ 201 nm) that manifests itself as a 'carrier' frequency of temporally shaped oscillations of the time-dependent expectation values ⟨z ⟩ and ⟨∂V/∂z ⟩ that emerge at the ends of the laser pulses and exist on a timescale of at least 50 fs. Time-dependent expectation values ⟨ρ⟩ and ⟨∂V /∂ρ⟩ of the optically passive degree of freedom, ρ, demonstrate post-laser-field oscillations at two basic frequencies ωρ1 ≈ ωosc and ωρ2 ≈ 2ωosc. Power spectra associated with the electronic motion show higher- and lower-order harmonics with respect to the driving field.

Reduction of Charge Traps and Stability Enhancement in Solution-Processed Organic Field-Effect Transistors Based on a Blended n-Type Semiconductor.

PubMed

Campos, Antonio; Riera-Galindo, Sergi; Puigdollers, Joaquim; Mas-Torrent, Marta

2018-05-09

Solution-processed n-type organic field-effect transistors (OFETs) are essential elements for developing large-area, low-cost, and all organic logic/complementary circuits. Nonetheless, the development of air-stable n-type organic semiconductors (OSCs) lags behind their p-type counterparts. The trapping of electrons at the semiconductor-dielectric interface leads to a lower performance and operational stability. Herein, we report printed small-molecule n-type OFETs based on a blend with a binder polymer, which enhances the device stability due to the improvement of the semiconductor-dielectric interface quality and a self-encapsulation. Both combined effects prevent the fast deterioration of the OSC. Additionally, a complementary metal-oxide semiconductor-like inverter is fabricated depositing p-type and n-type OSCs simultaneously.

Use of Portable Digital Devices to Analyze Autonomic Stress Response in Psychology Objective Structured Clinical Examination.

PubMed

Beltrán-Velasco, Ana Isabel; Bellido-Esteban, Alberto; Ruisoto-Palomera, Pablo; Clemente-Suárez, Vicente Javier

2018-01-12

The aim of the present study was to explore changes in the autonomic stress response of Psychology students in a Psychology Objective Structured Clinical Examination (OSCE) and their relationship with OSCE performance. Variables of autonomic modulation by the analysis of heart rate variability in temporal, frequency and non-linear domains, subjective perception of distress strait and academic performance were measured before and after the two different evaluations that composed the OSCE. A psychology objective structured clinical examination composed by two different evaluation scenarios produced a large anxiety anticipatory response, a habituation response in the first of the evaluation scenarios and a in the entire evaluation, and a no habituation response in the second evaluation scenario. Autonomic modulation parameters do not correlate with academic performance of students.

Do quality indicators for general practice teaching practices predict good outcomes for students?

PubMed

Bartlett, Maggie; Potts, Jessica; McKinley, Bob

2016-07-01

Keele medical students spend 113 days in general practices over our five-year programme. We collect practice data thought to indicate good quality teaching. We explored the relationships between these data and two outcomes for students; Objective Structured Clinical Examination (OSCE) scores and feedback regarding the placements. Though both are surrogate markers of good teaching, they are widely used. We collated practice and outcome data for one academic year. Two separate statistical analyses were carried out: (1) to determine how much of the variation seen in the OSCE scores was due to the effect of the practice and how much to the individual student. (2) to identify practice characteristics with a relationship to student feedback scores. (1) OSCE performance: 268 students in 90 practices: six quality indicators independently influenced the OSCE score, though without linear relationships and not to statistical significance. (2) Student satisfaction: 144 students in 69 practices: student feedback scores are not influenced by practice characteristics. The relationships between the quality indicators we collect for practices and outcomes for students are not clear. It may be that neither the quality indicators nor the outcome measures are reliable enough to inform decisions about practices' suitability for teaching.

Cost and logistics for implementing the American College of Surgeons objective structured clinical examination.

PubMed

Sudan, Ranjan; Clark, Philip; Henry, Brandon

2015-01-01

The American College of Surgeons has developed a reliable and valid OSCE (objective structured clinical examination) to assess the clinical skills of incoming postgraduate year 1 surgery residents, but the cost and logistics of implementation have not been described. Fixed costs included staff time, medical supplies, facility fee, standardized patient (SP) training time, and one OSCE session. Variable costs were incurred for additional OSCE sessions. Costs per resident were calculated and modeled for increasing the number of test takers. American College of Surgeons OSCE materials and examination facilities were free. Fixed costs included training 11 SPs for 4 hours ($1,540), moulage and simulation material ($469), and administrative effort for 44 hours ($2,200). Variable cost for each session was $1,540 (SP time). Total cost for the first session was $6,649 ($664/resident), decreased to $324/resident for 3 sessions, and projected to further decline to $239/resident for 6 sessions. The cost decreased as the number of residents tested increased. To manage costs, testing more trainees by regional collaboration is recommended. Copyright © 2015 Elsevier Inc. All rights reserved.

Curriculum gaps in teaching clinical skills to Iranian undergraduate medical students.

PubMed

Mirzazadeh, Azim; Bavarian, Behrouz; Labaf, Ali; Afshari, Ali; Nikoo, Mohammad; Meshkani, Zahra Sadat; Khashayar, Patricia

2013-04-20

The inefficacy of clinical skill education during the clerkship has been reported in several studies. The present study was conducted to evaluate the competency of medical students in performing several clinical skills through an Objective Structured Clinical Examination (OSCE), aiming to evaluate the quality of the existing curriculum in the clerkship phase. The cross sectional study was conducted at the end of the clerkship period, before the students had entered the internship. The OSCE exam was conducted in the morning (2 different tracts) and in the evening (2 similar tracts) and 86 students participated in the exam. Each tract consisted of seven stations. The students' points in the stations assessing history taking and clinical skills were compared. The students gained the highest points in the history taking stations, whereas the procedure stations accounted for the lowest points; there was a significant difference between these stations (p < 0.001). The female students achieved higher scores in the OSCE exam compared to males (p = 0.004). The OSCE exam revealed the inefficacy of the current medical curriculum in teaching the required clinical skill to undergraduate medical students during the clerkship.

Use of an Objective Structured Clinical Examination in Clinical Nurse Specialist Education.

PubMed

Cuevas, Heather E; Timmerman, Gayle M

2016-01-01

Helping patients maximize their potential using expert coaching to facilitate lifestyle change is an important practice area for clinical nurse specialists (CNSs). The purpose is to determine the usefulness of objective structured clinical examinations (OSCEs) for evaluating CNS students' coaching competencies in the context of facilitating lifestyle change. Despite the use of OSCEs to assess competencies in clinical skills (eg, performance of procedures, decision making), its potential for evaluating coaching competencies for lifestyle change has not been demonstrated. We developed 4 OSCEs dealing with coaching patients in exercise, weight loss, stress reduction, or nonpharmacologic management of hyperlipidemia. Evaluation criteria included (1) approach to the patient, (2) information gathering, (3) motivational interviewing, and (4) management (medical and behavioral strategies). Student performance ranged from highly organized with proficient coaching skills to disorganized and focused solely on clinical management and prescriptive communication. Student responses were positive. Objective structured clinical examinations were highly useful for evaluating CNS students' coaching competencies for lifestyle change. Using OSCEs early in the semester to provide students feedback on their performance and again at the end to determine improvement optimizes use of this teaching strategy.

Characterization of sulfur and nitrogen compounds in Brazilian petroleum derivatives using ionic liquid capillary columns in comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection.

PubMed

Cappelli Fontanive, Fernando; Souza-Silva, Érica Aparecida; Macedo da Silva, Juliana; Bastos Caramão, Elina; Alcaraz Zini, Claudia

2016-08-26

Diesel and naphtha samples were analyzed using ionic liquid (IL) columns to evaluate the best column set for the investigation of organic sulfur compounds (OSC) and nitrogen(N)-containing compounds analyses with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry detector (GC×GC/TOFMS). Employing a series of stationary phase sets, namely DB-5MS/DB-17, DB-17/DB-5MS, DB-5MS/IL-59, and IL-59/DB-5MS, the following parameters were systematically evaluated: number of tentatively identified OSC, 2D chromatographic space occupation, number of polyaromatic hydrocarbons (PAH) and OSC co-elutions, and percentage of asymmetric peaks. DB-5MS/IL-59 was chosen for OSC analysis, while IL59/DB-5MS was chosen for nitrogen compounds, as each stationary phase set provided the best chromatographic efficiency for these two classes of compounds, respectively. Most compounds were tentatively identified by Lee and Van den Dool and Kratz retention indexes, and spectra-matching to library. Whenever available, compounds were also positively identified via injection of authentic standards. Copyright © 2016 Elsevier B.V. All rights reserved.

Assessment Methods of an Undergraduate Psychiatry Course at a Saudi University

PubMed Central

Amr, Mostafa; Amin, Tarek

2012-01-01

Objectives: In Arab countries there are few studies on assessment methods in the field of psychiatry. The objective of this study was to assess the outcome of different forms of psychiatric course assessment among fifth year medical students at King Faisal University, Saudi Arabia. Methods: We examined the performance of 110 fifth-year medical students through objective structured clinical examinations (OSCE), traditional oral clinical examinations (TOCE), portfolios, multiple choice questions (MCQ), and a written examination. Results: The score ranges in TOCE, OSCE, portfolio, and MCQ were 32–50, 7–15, 5–10 and 22–45, respectively. In regression analysis, there was a significant correlation between OSCE and all forms of psychiatry examinations, except for the MCQ marks. OSCE accounted for 65.1% of the variance in total clinical marks and 31.5% of the final marks (P = 0.001), while TOCE alone accounted for 74.5% of the variance in the clinical scores. Conclusions: This study demonstrates a consistency among the students’ assessment methods used in the psychiatry course, particularly the clinical component, in an integrated manner. This information would be useful for future developments in undergraduate teaching. PMID:22548141

Range and energetics of charge hopping in organic semiconductors

NASA Astrophysics Data System (ADS)

Abdalla, Hassan; Zuo, Guangzheng; Kemerink, Martijn

2017-12-01

The recent upswing in attention for the thermoelectric properties of organic semiconductors (OSCs) adds urgency to the need for a quantitative description of the range and energetics of hopping transport in organic semiconductors under relevant circumstances, i.e., around room temperature (RT). In particular, the degree to which hops beyond the nearest neighbor must be accounted for at RT is still largely unknown. Here, measurements of charge and energy transport in doped OSCs are combined with analytical modeling to reach the univocal conclusion that variable-range hopping is the proper description in a large class of disordered OSC at RT. To obtain quantitative agreement with experiment, one needs to account for the modification of the density of states by ionized dopants. These Coulomb interactions give rise to a deep tail of trap states that is independent of the material's initial energetic disorder. Insertion of this effect into a classical Mott-type variable-range hopping model allows one to give a quantitative description of temperature-dependent conductivity and thermopower measurements on a wide range of disordered OSCs. In particular, the model explains the commonly observed quasiuniversal power-law relation between the Seebeck coefficient and the conductivity.

Significance of the gate voltage-dependent mobility in the electrical characterization of organic field effect transistors

NASA Astrophysics Data System (ADS)

Kim, Jong Beom; Lee, Dong Ryeol

2018-04-01

We studied the effect of the addition of free hole- and electron-rich organic molecules to organic semiconductors (OSCs) in organic field effect transistors (OFETs) on the gate voltage-dependent mobility. The drain current versus gate voltage characteristics were quantitatively analyzed using an OFET mobility model of power law behavior based on hopping transport in an OSC. This analysis distinguished the threshold voltage shifts, depending on the materials and structures of the OFET device, and properly estimated the hopping transport of the charge carriers induced by the gate bias within the OSC from the power law exponent parameter. The addition of pentacene or C60 molecules to a one-monolayer pentacene-based OFET shifted the threshold voltages negatively or positively, respectively, due to the structural changes that occurred in the OFET device. On the other hand, the power law parameters revealed that the addition of charge carriers of the same or opposite polarity enhanced or hindered hopping transport, respectively. This study revealed the need for a quantitative analysis of the gate voltage-dependent mobility while distinguishing this effect from the threshold voltage effect in order to understand OSC hopping transport in OFETs.

Role of the Charge-Transfer State in Reduced Langevin Recombination in Organic Solar Cells: A Theoretical Study

PubMed Central

2015-01-01

Reduced Langevin recombination has been observed in organic solar cells (OSCs) for many years, but its origin is still unclear. A recent work by Burke et al. (Adv. Energy Mater.2015, 5, 1500123-1) was inspired by this reduced Langevin recombination, and they proposed an equilibrium model of charge-transfer (CT) states that correlates the open-circuit voltage of OSCs with experimentally available device parameters. In this work, we extend Burke et al.’s CT model further and for the first time directly correlate the reduced Langevin recombination with the energetic and dynamic behavior of the CT state. Recombination through CT states leads in a straightforward manner to a decrease in the Langevin reduction factor with increasing temperature, without explicit consideration of the temperature dependence of the mobility. To verify the correlation between the CT states and reduced Langevin recombination, we incorporated this CT model and the reduced Langevin model into drift-diffusion simulations of a bilayer OSC. The simulations not only successfully reproduced realistic current–voltage (J–V) characteristics of the bilayer OSC, but also demonstrate that the two models consistently lead to same value of the apparent Langevin reduction factor. PMID:26640611

Reductive amination derivatization for the quantification of garlic components by isotope dilution analysis.

PubMed

Lin, Yi-Reng; Huang, Mei-Fang; Wu, You-Ying; Liu, Meng-Chieh; Huang, Jing-Heng; Chen, Ziyu; Shiue, Yow-Ling; Wu, Chia-En; Liang, Shih-Shin

2017-09-01

In this work, we synthesized internal standards for four garlic organosulfur compounds (OSCs) by reductive amination with 13 C, D 2 -formaldehyde, and developed an isotope dilution analysis method to quantitate these organosulfur components in garlic samples. Internal standards were synthesized for internal absolute quantification of S-allylcysteine (SAC), S-allylcysteine sulfoxide (alliin), S-methylcysteine (SMC), and S-ethylcysteine (SEC). We used a multiple reaction monitoring (MRM) to detect 13 C, D 2 -formaldehyde-modified OSCs by ultrahigh-performance liquid phase chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and obtained MS spectra showing different ratios of 13 C, D 2 -formaldehyde-modified and H 2 -formaldehyde-modified compounds. The resulting labeled and unlabeled OSCs were exhibited correlation coefficient (R 2 ) ranged from 0.9989 to 0.9994, respectively. The average recoveries for four OSCs at three concentration levels ranged from 89% to 105%. By 13 C, D 2 -formaldehyde and sodium cyanoborohydride, the reductive amination-based method can be utilized to generate novel internal standard for isotope dilution and to extend the quantitative application. Copyright © 2017 Elsevier Ltd. All rights reserved.

Study of various n-type organic semiconductors on ultraviolet detective and electroluminescent properties of optoelectronic integrated device

NASA Astrophysics Data System (ADS)

Deng, Chaoxu; Shao, Bingyao; Zhao, Dan; Zhou, Dianli; Yu, Junsheng

2017-11-01

Organic optoelectronic integrated device (OID) with both ultraviolet (UV) detective and electroluminescent (EL) properties was fabricated by using a thermally activated delayed fluorescence (TADF) semiconductor of (4s, 6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as an emitter. The effect of five kinds of n-type organic semiconductors (OSCs) on the enhancement of UV detective and EL properties of OID was systematically studied. The result shows that two orders of magnitude in UV detectivity from 109 to 1011 Jones and 3.3 folds of luminance from 2499 to 8233 cd m-2 could be achieved. The result shows that not only the difference of lowest unoccupied molecular orbital (LUMO) between active layer and OSC but also the variety of electron mobility have a significant effect on the UV detective and EL performance through adjusting electron injection/transport. Additionally, the optimized OSC thickness is beneficial to confine the leaking of holes from the active layer to cathode, leading to the decrease of dark current for high detective performance. This work provides a useful method on broadening OSC material selection and device architecture construction for the realization of high performance OID.

Ag-Pd-Cu alloy inserted transparent indium tin oxide electrodes for organic solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hyo-Joong; Seo, Ki-Won; Kim, Han-Ki, E-mail: imdlhkkim@khu.ac.kr

2014-09-01

The authors report on the characteristics of Ag-Pd-Cu (APC) alloy-inserted indium tin oxide (ITO) films sputtered on a glass substrate at room temperature for application as transparent anodes in organic solar cells (OSCs). The effect of the APC interlayer thickness on the electrical, optical, structural, and morphological properties of the ITO/APC/ITO multilayer were investigated and compared to those of ITO/Ag/ITO multilayer electrodes. At the optimized APC thickness of 8 nm, the ITO/APC/ITO multilayer exhibited a resistivity of 8.55 × 10{sup −5} Ω cm, an optical transmittance of 82.63%, and a figure-of-merit value of 13.54 × 10{sup −3} Ω{sup −1}, comparable to those of the ITO/Ag/ITOmore » multilayer. Unlike the ITO/Ag/ITO multilayer, agglomeration of the metal interlayer was effectively relieved with APC interlayer due to existence of Pd and Cu elements in the thin region of the APC interlayer. The OSCs fabricated on the ITO/APC/ITO multilayer showed higher power conversion efficiency than that of OSCs prepared on the ITO/Ag/ITO multilayer below 10 nm due to the flatness of the APC layer. The improved performance of the OSCs with ITO/APC/ITO multilayer electrodes indicates that the APC alloy interlayer prevents the agglomeration of the Ag-based metal interlayer and can decrease the thickness of the metal interlayer in the oxide-metal-oxide multilayer of high-performance OSCs.« less

Organic Solar Cells Based on WO2.72 Nanowire Anode Buffer Layer with Enhanced Power Conversion Efficiency and Ambient Stability.

PubMed

You, Longzhen; Liu, Bin; Liu, Tao; Fan, Bingbing; Cai, Yunhao; Guo, Lin; Sun, Yanming

2017-04-12

Tungsten oxide as an alternative to conventional acidic PEDOT:PSS has attracted much attention in organic solar cells (OSCs). However, the vacuum-processed WO 3 layer and high-temperature sol-gel hydrolyzed WO X are incompatible with large-scale manufacturing of OSCs. Here, we report for the first time that a specific tungsten oxide WO 2.72 (W 18 O 49 ) nanowire can function well as the anode buffer layer. The nw-WO 2.72 film exhibits a high optical transparency. The power conversion efficiency (PCE) of OSCs based on three typical polymer active layers PTB7:PC 71 BM, PTB7-Th:PC 71 BM, and PDBT-T1:PC 71 BM with nw-WO 2.72 layer were improved significantly from 7.27 to 8.23%, from 8.44 to 9.30%, and from 8.45 to 9.09%, respectively compared to devices with PEDOT:PSS. Moreover, the photovoltaic performance of OSCs based on small molecule p-DTS(FBTTh 2 ) 2 :PC 71 BM active layer was also enhanced with the incorporation of nw-WO 2.72 . The enhanced performance is mainly attributed to the improved short-circuit current density (J sc ), which benefits from the oxygen vacancies and the surface apophyses for better charge extraction. Furthermore, OSCs based on nw-WO 2.72 show obviously improved ambient stability compared to devices with PEDOT:PSS layer. The results suggest that nw-WO 2.72 is a promising candidate for the anode buffer layer materials in organic solar cells.

Acceptability and Impact of a Required Palliative Care Rotation with Prerotation and Postrotation Observed Simulated Clinical Experience during Internal Medicine Residency Training on Primary Palliative Communication Skills.

PubMed

Vergo, Maxwell T; Sachs, Sharona; MacMartin, Meredith A; Kirkland, Kathryn B; Cullinan, Amelia M; Stephens, Lisa A

2017-05-01

Improving communication training for primary palliative care using a required palliative care rotation for internal medicine (IM) residents has not been assessed. To assess skills acquisition and acceptability for IM residents not selecting an elective. A consecutive, single-arm cohort underwent preobjective structured clinical examination (OSCE) with learner-centric feedback, two weeks of clinical experience, and finally a post-OSCE to crystallize learner-centric take home points. IM second year residents from Dartmouth-Hitchcock were exposed to a required experiential palliative care rotation. Pre- and post-OSCE using a standardized score card for behavioral skills, including patient-centered interviewing, discussing goals of care/code status, and responding to emotion, as well as a confidential mixed qualitative and quantitative evaluation of the experience. Twelve residents were included in the educational program (two were excluded because of shortened experiences) and showed statistically significant improvements in overall communication and more specifically in discussing code status and responding to emotions. General patient-centered interviewing skills were not significantly improved, but prerotation scores reflected pre-existing competency in this domain. Residents viewed the observed simulated clinical experience (OSCE) and required rotation as positive experiences, but wished for more opportunities to practice communication skills in real clinical encounters. A required palliative care experiential rotation flanked by OSCEs at our institution improved the acquisition of primary palliative care communication skills similarly to other nonclinical educational platforms, but may better meet the needs of the resident and faculty as well as address all required ACGME milestones.

Development of a tool to support holistic generic assessment of clinical procedure skills.

PubMed

McKinley, Robert K; Strand, Janice; Gray, Tracey; Schuwirth, Lambert; Alun-Jones, Tom; Miller, Helen

2008-06-01

The challenges of maintaining comprehensive banks of valid checklists make context-specific checklists for assessment of clinical procedural skills problematic. This paper reports the development of a tool which supports generic holistic assessment of clinical procedural skills. We carried out a literature review, focus groups and non-participant observation of assessments with interview of participants, participant evaluation of a pilot objective structured clinical examination (OSCE), a national modified Delphi study with prior definitions of consensus and an OSCE. Participants were volunteers from a large acute teaching trust, a teaching primary care trust and a national sample of National Health Service staff. Results In total, 86 students, trainees and staff took part in the focus groups, observation of assessments and pilot OSCE, 252 in the Delphi study and 46 candidates and 50 assessors in the final OSCE. We developed a prototype tool with 5 broad categories amongst which were distributed 38 component competencies. There was > 70% agreement (our prior definition of consensus) at the first round of the Delphi study for inclusion of all categories and themes and no consensus for inclusion of additional categories or themes. Generalisability was 0.76. An OSCE based on the instrument has a predicted reliability of 0.79 with 12 stations and 1 assessor per station or 10 stations and 2 assessors per station. This clinical procedural skills assessment tool enables reliable assessment and has content and face validity for the assessment of clinical procedural skills. We have designated it the Leicester Clinical Procedure Assessment Tool (LCAT).

Aluminum-doped ceria-zirconia solid solutions with enhanced thermal stability and high oxygen storage capacity.

PubMed

Dong, Qiang; Yin, Shu; Guo, Chongshen; Sato, Tsugio

2012-10-01

A facile solvothermal method to synthesize aluminum-doped ceria-zirconia (Ce0.5Zr0.5-xAlxO2-x/2, x = 0.1 to 0.4) solid solutions was carried out using Ce(NH4)2(NO3)6, Zr(NO3)3·2H2O Al(NO3)3·9H2O, and NH4OH as the starting materials at 200°C for 24 h. The obtained solid solutions from the solvothermal reaction were calcined at 1,000°C for 20 h in air atmosphere to evaluate the thermal stability. The synthesized Ce0.5Zr0.3Al0.2O1.9 particle was characterized for the oxygen storage capacity (OSC) in automotive catalysis. For the characterization, X-ray diffraction, transmission electron microscopy, and the Brunauer-Emmet-Teller (BET) technique were employed. The OSC values of all samples were measured at 600°C using thermogravimetric-differential thermal analysis. Ce0.5Zr0.3Al0.2O1.9 solid solutions calcined at 1,000°C for 20 h with a BET surface area of 18 m2 g-1 exhibited a considerably high OSC of 427 μmol-O g-1 and good OSC performance stability. The same synthesis route was employed for the preparation of the CeO2 and Ce0.5Zr0.5O2. The incorporation of aluminum ion in the lattice of ceria-based catalyst greatly enhanced the thermal stability and OSC.

Community-based evaluation of laparoscopic versus open simple closure of perforated peptic ulcers.

PubMed

Kuwabara, Kazuaki; Matsuda, Shinya; Fushimi, Kiyohide; Ishikawa, Koichi B; Horiguchi, Hiromasa; Fujimori, Kenji

2011-11-01

Several studies have advocated laparoscopic simple closure (LSC) as the treatment of choice for perforated peptic ulcer disease (PUD). However, there has been no comprehensive community-based evaluation of the advantages of using LSC over open simple closure (OSC). Using an administrative database, we evaluated LSC versus OSC for patients with perforated ulcers. From 6,334 patients with perforated ulcers, we identified 2,909 simple closure cases between 2006 and 2010. Study variables were demographics, mortality, co-morbidities, complications, ulcer location, surgical timing, blood transfusion, postoperative ventilation, operating room (OR) time, time to resumption of oral food intake, length of stay (LOS), and total charges. After matching patient baseline variables between OSC and LSC, we performed multivariate analyses to assess the impacts of LSC on mortality, complications, and ventilation administration. A total of 2,073 OSC cases and 836 LSC cases were identified in 670 hospitals. Younger age, duodenal ulcer, and pre-existing PUD were indicators for selection of LSC. Matching analysis indicated a correlation between LSC and lower mortality, less frequent postoperative and overall blood transfusion, shorter LOS, earlier return to oral intake, and longer OR time. There was no difference between OSC and LSC in complication rate or mortality. Longer OR time was correlated with a higher complication rate and the need for ventilation, the latter of which was independently associated with an increase in mortality. Because longer OR time was associated with more frequent complications and ventilation, surgeons should obtain the skills and strategies necessary to accomplish LSC without extending OR time improperly.

Correlation of ALDH1 and Notch3 Expression: Clinical implication in Ovarian Carcinomas.

PubMed

Kim, Mi Joung; Kim, A-Ram; Jeong, Ju-Yeon; Kim, Kwang-Il; Kim, Tae-Heon; Lee, Chan; Chung, Kwanghoe; Ko, Young-Hyeh; An, Hee-Jung

2017-01-01

Purpose : ALDH1 is a putative cancer stem cell marker, while the Notch signaling pathway is involved in regulation of cancer stem cell (CSC)s. This study aims to determine the expression of Notch signaling genes in ovarian CSCs, and to assess the clinical impact of expression of ALDH1 and Notch signaling genes in ovarian cancers. Methods : We examined expression of Notch signaling genes in FACS-sorted ALDH1(+) putative ovarian CSCs and expression of ALDH1 and Notch signaling genes in 86 ovarian epithelial tumors and various ovarian cancer cell lines by real-time RT-PCR, including Notch receptors ( Notch1-4 ), Notch ligands ( Jagged1 and Jagged2 ), and the downstream molecule, Hes1 . Furthermore, we correlated their expression with clinicopathological parameters and patient's survival in ovarian serous carcinoma (OSC)s, the most prevalent type of ovarian cancer. Results : The higher expression levels of ALDH1 and Notch related genes, especially Notch3 were associated with CSCs and with chemoresistant OSCs and paclitaxel-resistant SKpac ovarian cancer cells. Among the Notch signaling genes, high Notch3 expression was significantly associated with all the parameters of poor prognosis, i.e., advanced stage, lymph node and distant metastases, and chemoresistance, whereas other genes were less correlated with these parameters. A combined upregulation of ALDH1 and Notch3 was an independent poor prognostic factor in OSCs. Conclusions : ALDH1 correlates with Notch3 expression in ovarian carcinomas. ALDH1 and Notch3 overexpression is an independent poor prognostic indicator for worse patient's survival in this subset of OSCs.

Standard Setting Methods for Pass/Fail Decisions on High-Stakes Objective Structured Clinical Examinations: A Validity Study.

PubMed

Yousuf, Naveed; Violato, Claudio; Zuberi, Rukhsana W

2015-01-01

CONSTRUCT: Authentic standard setting methods will demonstrate high convergent validity evidence of their outcomes, that is, cutoff scores and pass/fail decisions, with most other methods when compared with each other. The objective structured clinical examination (OSCE) was established for valid, reliable, and objective assessment of clinical skills in health professions education. Various standard setting methods have been proposed to identify objective, reliable, and valid cutoff scores on OSCEs. These methods may identify different cutoff scores for the same examinations. Identification of valid and reliable cutoff scores for OSCEs remains an important issue and a challenge. Thirty OSCE stations administered at least twice in the years 2010-2012 to 393 medical students in Years 2 and 3 at Aga Khan University are included. Psychometric properties of the scores are determined. Cutoff scores and pass/fail decisions of Wijnen, Cohen, Mean-1.5SD, Mean-1SD, Angoff, borderline group and borderline regression (BL-R) methods are compared with each other and with three variants of cluster analysis using repeated measures analysis of variance and Cohen's kappa. The mean psychometric indices on the 30 OSCE stations are reliability coefficient = 0.76 (SD = 0.12); standard error of measurement = 5.66 (SD = 1.38); coefficient of determination = 0.47 (SD = 0.19), and intergrade discrimination = 7.19 (SD = 1.89). BL-R and Wijnen methods show the highest convergent validity evidence among other methods on the defined criteria. Angoff and Mean-1.5SD demonstrated least convergent validity evidence. The three cluster variants showed substantial convergent validity with borderline methods. Although there was a high level of convergent validity of Wijnen method, it lacks the theoretical strength to be used for competency-based assessments. The BL-R method is found to show the highest convergent validity evidences for OSCEs with other standard setting methods used in the present study

Simulation-based end-of-life care training during surgical clerkship: assessment of skills and perceptions.

PubMed

Parikh, Priti P; Brown, Ronald; White, Mary; Markert, Ronald J; Eustace, Rosemary; Tchorz, Kathryn

2015-06-15

Assessment of interpersonal and psychosocial competencies during end-of-life care training is essential. This study reports the relationship between simulation-based end-of-life care Objective Structured Clinical Examination ratings and communication skills, trust, and self-assessed empathy along with the perceptions of students regarding their training experiences. Medical students underwent simulation-based end-of-life care OSCE training that involved standardized patients who evaluated students' communication skills and physician trust with the Kalamazoo Essential Elements Communication Checklist and the Wake Forest Physician Trust Scale. Students also completed the Jefferson Scale of Physician Empathy. Pearson correlation was used to examine the relationship between OSCE performance grades and communication, trust, and empathy scores. Student comments were analyzed using the constant comparative method of analysis to identify dominant themes. The 389 students (mean age 26.6 ± 2.8 y; 54.5% female) had OSCE grades that were positively correlated with physician trust scores (r = 0.325, P < 0.01) and communication skills (r = 0.383, P < 0.01). However, OSCE grades and self-reported empathy were not related (r = 0.021, P = 0.68). Time of clerkship differed for OSCE grade and physician trust scores; however, there was no trend identified. No differences were noted between the time of clerkship and communication skills or empathy. Overall, students perceived simulation-based end-of-life care training to be a valuable learning experience and appreciated its placement early in clinical training. We found that simulation-based OSCE training in palliative and end-of-life care can be effectively conducted during a surgery clerkship. Moreover, the standardized patient encounters combined with the formal assessment of communication skills, physician trust, and empathy provide feedback to students at an early phase of their professional life. The positive and appreciative

Civic engagement among orphans and non-orphans in five low- and middle-income countries.

PubMed

Gray, Christine L; Pence, Brian W; Messer, Lynne C; Ostermann, Jan; Whetten, Rachel A; Thielman, Nathan M; O'Donnell, Karen; Whetten, Kathryn

2016-10-11

Communities and nations seeking to foster social responsibility in their youth are interested in understanding factors that predict and promote youth involvement in public activities. Orphans and separated children (OSC) are a vulnerable population whose numbers are increasing, particularly in resource-poor settings. Understanding whether and how OSC are engaged in civic activities is important for community and world leaders who need to provide care for OSC and ensure their involvement in sustainable development. The Positive Outcomes for Orphans study (POFO) is a multi-country, longitudinal cohort study of OSC randomly sampled from institution-based care and from family-based care, and of non-OSC sampled from the same study regions. Participants represent six sites in five low-and middle-income countries. We examined civic engagement activities and government trust among subjects > =16 years old at 90-month follow-up (approximately 7.5 years after baseline). We calculated prevalences and estimated the association between key demographic variables and prevalence of regular volunteer work using multivariable Poisson regression, with sampling weights to accounting for the complex sampling design. Among the 1,281 POFO participants > =16 who were assessed at 90-month follow-up, 45 % participated in regular community service or volunteer work; two-thirds of those volunteers did so on a strictly voluntary basis. While government trust was fairly high, at approximately 70 % for each level of government, participation in voting was only 15 % among those who were > =18 years old. We did not observe significant associations between demographic characteristics and regular volunteer work, with the exception of large variation by study site. As the world's leaders grapple with the many competing demands of global health, economic security, and governmental stability, the participation of today's youth in community and governance is essential for

Respiratory modulation of oscillometric cuff pressure pulses and Korotkoff sounds during clinical blood pressure measurement in healthy adults.

PubMed

Chen, Diliang; Chen, Fei; Murray, Alan; Zheng, Dingchang

2016-05-10

Accurate blood pressure (BP) measurement depends on the reliability of oscillometric cuff pressure pulses (OscP) and Korotkoff sounds (KorS) for automated oscillometric and manual techniques. It has been widely accepted that respiration is one of the main factors affecting BP measurement. However, little is known about how respiration affects the signals from which BP measurement is obtained. The aim was to quantify the modulation effect of respiration on oscillometric pulses and KorS during clinical BP measurement. Systolic and diastolic BPs were measured manually from 40 healthy subjects (from 23 to 65 years old) under normal and regular deep breathing. The following signals were digitally recorded during linear cuff deflation: chest motion from a magnetometer to obtain reference respiration, cuff pressure from an electronic pressure sensor to derive OscP, and KorS from a digital stethoscope. The effects of respiration on both OscP and KorS were determined from changes in their amplitude associated with respiration between systole and diastole. These changes were normalized to the mean signal amplitude of OscP and KorS to derive the respiratory modulation depth. Reference respiration frequency, and the frequencies derived from the amplitude modulation of OscP and KorS were also calculated and compared. Respiratory modulation depth was 14 and 40 % for OscP and KorS respectively under normal breathing condition, with significant increases (both p < 0.05) to 16 and 49 % with deeper breathing. There was no statistically significant difference between the reference respiration frequency and those derived from the oscillometric and Korotkoff signals (both p > 0.05) during deep breathing, and for the oscillometric signal during normal breathing (p > 0.05). Our study confirmed and quantified the respiratory modulation effect on the oscillometric pulses and KorS during clinical BP measurement, with increased modulation depth under regular deeper breathing.

Impact of a Student-Driven, Virtual Patient Application on Objective Structured Clinical Examination Performance: Observational Study.

PubMed

Bergeron, David; Champagne, Jean-Nicolas; Qi, Wen; Dion, Maxime; Thériault, Julie; Renaud, Jean-Sébastien

2018-02-22

Peer-assisted learning (PAL) refers to a learning activity whereby students of similar academic level teach and learn from one another. Groupe de perfectionnement des habiletés cliniques (Clinical Skills Improvement Group), a student organization at Université Laval, Canada, propelled PAL into the digital era by creating a collaborative virtual patient platform. Medical interviews can be completed in pairs (a student-patient and a student-doctor) through an interactive Web-based application, which generates a score (weighted for key questions) and automated feedback. The aim of the study was to measure the pedagogical impact of the application on the score at medical interview stations at the summative preclerkship Objective Structured Clinical Examination (OSCE). We measured the use of the application (cases completed, mean score) in the 2 months preceding the OSCE. We also accessed the results of medical interview stations at the preclerkship summative OSCE. We analyzed whether using the application was associated with higher scores and/or better passing grades (≥60%) at the OSCE. Finally, we produced an online form where students could comment on their appreciation of the application. Of the 206 students completing the preclerkship summative OSCE, 170 (82.5%) were registered users on the application, completing a total of 3133 cases (18 by active user in average, 7 minutes by case in average). The appreciation questionnaire was answered online by 45 students who mentioned appreciating the intuitive, easy-to-use, and interactive design, the diversity of cases, and the automated feedback. Using the application was associated with reduced reported stress, improved scores (P=.04), and improved passing rates (P=.11) at the preclerkship summative OSCE. This study suggests that PAL can go far beyond small-group teaching, showing students' potential to create helpful pedagogical tools for their peers. ©David Bergeron, Jean-Nicolas Champagne, Wen Qi, Maxime Dion

Objective structured clinical examination "Death Certificate" station - Computer-based versus conventional exam format.

PubMed

Biolik, A; Heide, S; Lessig, R; Hachmann, V; Stoevesandt, D; Kellner, J; Jäschke, C; Watzke, S

2018-04-01

One option for improving the quality of medical post mortem examinations is through intensified training of medical students, especially in countries where such a requirement exists regardless of the area of specialisation. For this reason, new teaching and learning methods on this topic have recently been introduced. These new approaches include e-learning modules or SkillsLab stations; one way to objectify the resultant learning outcomes is by means of the OSCE process. However, despite offering several advantages, this examination format also requires considerable resources, in particular in regards to medical examiners. For this reason, many clinical disciplines have already implemented computer-based OSCE examination formats. This study investigates whether the conventional exam format for the OSCE forensic "Death Certificate" station could be replaced with a computer-based approach in future. For this study, 123 students completed the OSCE "Death Certificate" station, using both a computer-based and conventional format, half starting with the Computer the other starting with the conventional approach in their OSCE rotation. Assignment of examination cases was random. The examination results for the two stations were compared and both overall results and the individual items of the exam checklist were analysed by means of inferential statistics. Following statistical analysis of examination cases of varying difficulty levels and correction of the repeated measures effect, the results of both examination formats appear to be comparable. Thus, in the descriptive item analysis, while there were some significant differences between the computer-based and conventional OSCE stations, these differences were not reflected in the overall results after a correction factor was applied (e.g. point deductions for assistance from the medical examiner was possible only at the conventional station). Thus, we demonstrate that the computer-based OSCE "Death Certificate" station

Flow-Directed Crystallization for Printed Electronics.

PubMed

Qu, Ge; Kwok, Justin J; Diao, Ying

2016-12-20

The solution printability of organic semiconductors (OSCs) represents a distinct advantage for materials processing, enabling low-cost, high-throughput, and energy-efficient manufacturing with new form factors that are flexible, stretchable, and transparent. While the electronic performance of OSCs is not comparable to that of crystalline silicon, the solution processability of OSCs allows them to complement silicon by tackling challenging aspects for conventional photolithography, such as large-area electronics manufacturing. Despite this, controlling the highly nonequilibrium morphology evolution during OSC printing remains a challenge, hindering the achievement of high electronic device performance and the elucidation of structure-property relationships. Many elegant morphological control methodologies have been developed in recent years including molecular design and novel processing approaches, but few have utilized fluid flow to control morphology in OSC thin films. In this Account, we discuss flow-directed crystallization as an effective strategy for controlling the crystallization kinetics during printing of small molecule and polymer semiconductors. Introducing the concept of flow-directed crystallization to the field of printed electronics is inspired by recent advances in pharmaceutical manufacturing and flow processing of flexible-chain polymers. Although flow-induced crystallization is well studied in these areas, previous findings may not apply directly to the field of printed electronics where the molecular structures (i.e., rigid π-conjugated backbone decorated with flexible side chains) and the intermolecular interactions (i.e., π-π interactions, quadrupole interactions) of OSCs differ substantially from those of pharmaceuticals or flexible-chain polymers. Another critical difference is the important role of solvent evaporation in open systems, which defines the flow characteristics and determines the crystallization kinetics and pathways. In

Introduction to Orbital Sciences Corporation

NASA Technical Reports Server (NTRS)

1991-01-01

A general overview of the Orbital Sciences Corporation (OSC) is presented. The following topics are covered: (1) manpower, facilities, and financial growth; (2) organization and management team; (3) the Space Data Division organization; (4) the Chandler facility; (5) Space Data-Products and Services; (6) space transportation systems; (7) spacecraft and space support systems; (8) turn-key suborbital launch services and support systems; and (9) OSC suborbital booster performance.

Albania’s Counter-Terrorism Policy Options: Finding a Strategy of Common Sense

DTIC Science & Technology

2004-06-01

OSCE, February 2004. http://www.osce.org/documents/pia/2004/02/2117_en.pdf ( accessed 20 March 2004). Luarasi, Aleks. Historia e Institucioneve...Terrorism 1999, http://www.state.gov/www/global/terrorism/1999report/europe.html#Albania ( accessed 20 January 2004). 2 terrorism threat, review the...Balkan Stability? Balkan Report, no.153 (Brussels: ICG 25 February 2004). http://www.crisisweb.org/home/index.cfm?id=1239&l=1 ( accessed 10 January

Improving antibiotic prescribing skills in medical students: the effect of e-learning after 6 months.

PubMed

Sikkens, Jonne J; Caris, Martine G; Schutte, Tim; Kramer, Mark H H; Tichelaar, Jelle; van Agtmael, Michiel A

2018-05-09

Antimicrobial prescribing behaviour is first established during medical study, but teachers often cite lack of time as an important problem in the implementation of antimicrobial stewardship in the medical curriculum. The use of electronic learning (e-learning) is a potentially time-efficient solution, but its effectiveness in changing long-term prescribing behaviour in medical students is as yet unknown. We performed a prospective controlled intervention study of the long-term effects of a short interactive e-learning course among fourth year medical students in a Dutch university. The e-learning was temporarily implemented as a non-compulsory course during a 6 week period. Six months later, all students underwent an infectious disease-based objective structured clinical examination (OSCE) aimed at simulating postgraduate prescribing. If they passed, each student did the OSCE only once. We created a control group of students from a period when the e-learning was not implemented. Main outcomes were the OSCE pass percentage and knowledge, drug choice and overall scores. We used propensity scores to create equal comparisons. We included 71 students in the intervention group and 285 students in the control group. E-learning participation in the intervention group was 81%. The OSCE pass percentage was 86% in the control group versus 97% in the intervention group (+11%, OR 5.9, 95% CI 1.7-20.0). OSCE overall, knowledge and drug choice grades (1-10) were also significantly higher in the intervention group (differences +0.31, +0.31 and +0.51, respectively). E-learning during a limited period can significantly improve medical students' performance of an antimicrobial therapeutic consultation in a situation simulating clinical practice 6 months later.

Multilevel Safety Climate and Safety Performance in the Construction Industry: Development and Validation of a Top-Down Mechanism

PubMed Central

Gao, Ran; Chan, Albert P.C.; Utama, Wahyudi P.; Zahoor, Hafiz

2016-01-01

The character of construction projects exposes front-line workers to dangers and accidents. Safety climate has been confirmed to be a predictor of safety performance in the construction industry. This study aims to explore the underlying mechanisms of the relationship between multilevel safety climate and safety performance. An integrated model was developed to study how particular safety climate factors of one level affect those of other levels, and then affect safety performance from the top down. A questionnaire survey was administered on six construction sites in Vietnam. A total of 1030 valid questionnaires were collected from this survey. Approximately half of the data were used to conduct exploratory factor analysis (EFA) and the remaining data were submitted to structural equation modeling (SEM). Top management commitment (TMC) and supervisors’ expectation (SE) were identified as factors to represent organizational safety climate (OSC) and supervisor safety climate (SSC), respectively, and coworkers’ caring and communication (CCC) and coworkers’ role models (CRM) were identified as factors to denote coworker safety climate (CSC). SEM results show that OSC factor is positively related to SSC factor and CSC factors significantly. SSC factor could partially mediate the relationship between OSC factor and CSC factors, as well as the relationship between OSC factor and safety performance. CSC factors partially mediate the relationship between OSC factor and safety performance, and the relationship between SSC factor and safety performance. The findings imply that a positive safety culture should be established both at the organizational level and the group level. Efforts from all top management, supervisors, and coworkers should be provided to improve safety performance in the construction industry. PMID:27834823

High-throughput differentiation of heparin from other glycosaminoglycans by pyrolysis mass spectrometry.

PubMed

Nemes, Peter; Hoover, William J; Keire, David A

2013-08-06

Sensors with high chemical specificity and enhanced sample throughput are vital to screening food products and medical devices for chemical or biochemical contaminants that may pose a threat to public health. For example, the rapid detection of oversulfated chondroitin sulfate (OSCS) in heparin could prevent reoccurrence of heparin adulteration that caused hundreds of severe adverse events including deaths worldwide in 2007-2008. Here, rapid pyrolysis is integrated with direct analysis in real time (DART) mass spectrometry to rapidly screen major glycosaminoglycans, including heparin, chondroitin sulfate A, dermatan sulfate, and OSCS. The results demonstrate that, compared to traditional liquid chromatography-based analyses, pyrolysis mass spectrometry achieved at least 250-fold higher sample throughput and was compatible with samples volume-limited to about 300 nL. Pyrolysis yielded an abundance of fragment ions (e.g., 150 different m/z species), many of which were specific to the parent compound. Using multivariate and statistical data analysis models, these data enabled facile differentiation of the glycosaminoglycans with high throughput. After method development was completed, authentically contaminated samples obtained during the heparin crisis by the FDA were analyzed in a blinded manner for OSCS contamination. The lower limit of differentiation and detection were 0.1% (w/w) OSCS in heparin and 100 ng/μL (20 ng) OSCS in water, respectively. For quantitative purposes the linear dynamic range spanned approximately 3 orders of magnitude. Moreover, this chemical readout was successfully employed to find clues in the manufacturing history of the heparin samples that can be used for surveillance purposes. The presented technology and data analysis protocols are anticipated to be readily adaptable to other chemical and biochemical agents and volume-limited samples.

Electrohydrodynamic spinning of random-textured silver webs for electrodes embedded in flexible organic solar cells

NASA Astrophysics Data System (ADS)

Yoon, Dai Geon; Chin, Byung Doo; Bail, Robert

2017-03-01

A convenient process for fabricating a transparent conducting electrode on a flexible substrate is essential for numerous low-cost optoelectronic devices, including organic solar cells (OSCs), touch sensors, and free-form lighting applications. Solution-processed metal-nanowire arrays are attractive due to their low sheet resistance and optical clarity. However, the limited conductance at wire junctions and the rough surface topology still need improvement. Here, we present a facile process of electrohydrodynamic spinning using a silver (Ag) - polymer composite paste with high viscosity. Unlike the metal-nanofiber web formed by conventional electrospinning, a relatively thick, but still invisible-to-naked eye, Ag-web random pattern was formed on a glass substrate. The process parameters such as the nozzle diameter, voltage, flow rate, standoff height, and nozzle-scanning speed, were systematically engineered. The formed random texture Ag webs were embedded in a flexible substrate by in-situ photo-polymerization, release from the glass substrate, and post-annealing. OSCs with a donor-acceptor polymeric heterojunction photoactive layer were prepared on the Ag-web-embedded flexible films with various Ag-web densities. The short-circuit current and the power conversion efficiency of an OSC with a Ag-web-embedded electrode were not as high as those of the control sample with an indium-tin-oxide electrode. However, the Ag-web textures embedded in the OSC served well as electrodes when bent (6-mm radius), showing a power conversion efficiency of 2.06% (2.72% for the flat OSC), and the electrical stability of the Ag-web-textured patterns was maintained for up to 1,000 cycles of bending.

Multilevel Safety Climate and Safety Performance in the Construction Industry: Development and Validation of a Top-Down Mechanism.

PubMed

Gao, Ran; Chan, Albert P C; Utama, Wahyudi P; Zahoor, Hafiz

2016-11-08

The character of construction projects exposes front-line workers to dangers and accidents. Safety climate has been confirmed to be a predictor of safety performance in the construction industry. This study aims to explore the underlying mechanisms of the relationship between multilevel safety climate and safety performance. An integrated model was developed to study how particular safety climate factors of one level affect those of other levels, and then affect safety performance from the top down. A questionnaire survey was administered on six construction sites in Vietnam. A total of 1030 valid questionnaires were collected from this survey. Approximately half of the data were used to conduct exploratory factor analysis (EFA) and the remaining data were submitted to structural equation modeling (SEM). Top management commitment (TMC) and supervisors' expectation (SE) were identified as factors to represent organizational safety climate (OSC) and supervisor safety climate (SSC), respectively, and coworkers' caring and communication (CCC) and coworkers' role models (CRM) were identified as factors to denote coworker safety climate (CSC). SEM results show that OSC factor is positively related to SSC factor and CSC factors significantly. SSC factor could partially mediate the relationship between OSC factor and CSC factors, as well as the relationship between OSC factor and safety performance. CSC factors partially mediate the relationship between OSC factor and safety performance, and the relationship between SSC factor and safety performance. The findings imply that a positive safety culture should be established both at the organizational level and the group level. Efforts from all top management, supervisors, and coworkers should be provided to improve safety performance in the construction industry.

Does a Rater's Professional Background Influence Communication Skills Assessment?

PubMed

Artemiou, Elpida; Hecker, Kent G; Adams, Cindy L; Coe, Jason B

2015-01-01

There is increasing pressure in veterinary education to teach and assess communication skills, with the Objective Structured Clinical Examination (OSCE) being the most common assessment method. Previous research reveals that raters are a large source of variance in OSCEs. This study focused on examining the effect of raters' professional background as a source of variance when assessing students' communication skills. Twenty-three raters were categorized according to their professional background: clinical sciences (n=11), basic sciences (n=4), clinical communication (n=5), or hospital administrator/clinical skills technicians (n=3). Raters from each professional background were assigned to the same station and assessed the same students during two four-station OSCEs. Students were in year 2 of their pre-clinical program. Repeated-measures ANOVA results showed that OSCE scores awarded by the rater groups differed significantly: (F(matched_station_1) [2,91]=6.97, p=.002), (F(matched_station_2) [3,90]=13.95, p=.001), (F(matched_station_3) [3,90]=8.76, p=.001), and ((Fmatched_station_4) [2,91]=30.60, p=.001). A significant time effect between the two OSCEs was calculated for matched stations 1, 2, and 4, indicating improved student performances. Raters with a clinical communication skills background assigned scores that were significantly lower compared to the other rater groups. Analysis of written feedback provided by the clinical sciences raters showed that they were influenced by the students' clinical knowledge of the case and that they did not rely solely on the communication checklist items. This study shows that it is important to consider rater background both in recruitment and training programs for communication skills' assessment.

Expression pattern of RAGE and IGF-1 in the human fetal ovary and ovarian serous carcinoma.

PubMed

Poljicanin, Ana; Filipovic, Natalija; Vukusic Pusic, Tanja; Soljic, Violeta; Caric, Ana; Saraga-Babic, Mirna; Vukojevic, Katarina

2015-01-01

The expression pattern of RAGE and IGF-1 proteins in different ovarian cell lineages was histologically analyzed in six fetal, nine adult human ovaries, and nine serous ovarian carcinomas (OSC) using immunohistochemical methods. Mild expression of IGF-1 in ovarian surface epithelium (Ose) and oocytes in the 15-week human ovaries increased to moderate or strong in the stromal cells, oocytes and follicular cells in week 22. Occasional mild RAGE expression was observed in Ose during week 15, while strong expression characterized primordial follicles in week 22. In the reproductive human ovary, IGF-1 was mildly to moderately expressed in all ovarian cell lineages except in theca cells of the tertiary follicle where IGF-1 was negative. RAGE was strongly positive in the granulosa cells and some theca cells of the tertiary follicle, while negative to mildly positive in all cells of the secondary follicle. In the postmenopausal human ovary IGF-1 and RAGE were mildly expressed in Ose and stroma. In OSC, cells were strongly positive to IGF-1 and RAGE, except for some negative stromal cells. Different levels of IGF-1 and RAGE co-expression characterized fetal ovarian cells during development. In reproductive ovaries, IGF-1 and RAGE were co-localized in the granulosa and theca interna cells of tertiary follicles, while in postmenopausal ovaries and OSC, IGF-1 and RAGE were co-localized in Ose and OSC cells respectively. Our results indicate that intracellular levels of IGF-1 and RAGE protein might regulate the final destiny of the ovarian cell populations prior and during folliculogenesis, possibly controlling the metastatic potential of OSC as well. Copyright © 2015. Published by Elsevier GmbH.

Assessing cultural competency skills in gastroenterology fellowship training.

PubMed

Balzora, Sophie; Abiri, Benjamin; Wang, Xiao-Jing; McKeever, James; Poles, Michael; Zabar, Sondra; Gillespie, Colleen; Weinshel, Elizabeth

2015-02-14

To assess and teach cultural competency skills at the fellowship training level through the use of objective structured clinical examinations (OSCEs). We revised four scenarios to infuse a specific focus on cross-cultural care, and to render them appropriate for gastroenterology fellows. Three are discussed here: (1) Poor Health Literacy; (2) Disclosing/Apologizing for a Complication to a Patient Who Mistrusts the Healthcare System; and (3) Breaking Bad News to a Fatalistic Patient. A fourth case emphasizing shared decision-making will be described elsewhere. Four stations were completed by fellows and observed live by four faculty members, and the fellows' performance was assessed. Eleven fellows from four programs participated in the four OSCE. In the "Poor Health Literacy" case, 18% (2/11) of participants recognized that the standardized patient (SP) had below-basic health literacy. None successfully evaluated the SP's reading skills in a culturally-sensitive manner. In "Disclosing/Apologizing for a Complication", 4/11 (36%) personally apologized for the complication. 1/11 recognized the SP's mistrust of the medical system. With "Breaking Bad News", 27% (3/11) explored the patient's values to identify her fatalistic beliefs. OSCEs can be used to assess deficiencies in culturally-competent care at the fellowship level. OSCEs also afford fellowships the opportunity to inform future training curricula.

Ultrathin Organic Solar Cells with a Power Conversion Efficiency of Over ≈13.0%, Based on the Spatial Corrugation of the Metal Electrode-Cathode Fabry-Perot Cavity.

PubMed

In, Sungjun; Park, Namkyoo

2018-04-01

The application of nanophotonic structures for organic solar cells (OSCs) is quite popular and successful, and has led to increased optical absorption, better spectral overlap with solar irradiances, and improved charge collection. Significant improvements in the power conversion efficiency (PCE) have also been reported, exceeding 11%. Nonetheless, with the given material properties of OSCs with low optical absorption, narrow spectrum, short transport length of carriers, and nonuniform photocarrier generations resulting from the nanophotonic structure, the PCE of single-junction OSCs has been stagnant over the past few years, at a barrier of 12%. Here, an ultrathin inverted OSC structure with the highest efficiency of ≈13.0%, while being made from widely used organic materials, is demonstrated. By introducing a smooth spatial corrugation to the vertical plasmonic cavity enclosing the active layer, in-plane propagation modes and hybridized Fabry-Perot cavity modes inside the corrugated cavity are derived to achieve an ultralow Q , uniform coverage of optical absorption, in addition to uniform photocarrier generation and transport. As the first demonstration of ultra-broadband absorption with the introduction of spatial corrugation to the ultrathin metal film electrode-cathode Fabry-Perot cavity, future applications of the same concept in other light-harvesting devices utilizing different materials and structures are expected.

High-Efficiency Small Molecule-Based Bulk-Heterojunction Solar Cells Enhanced by Additive Annealing.

PubMed

Li, Lisheng; Xiao, Liangang; Qin, Hongmei; Gao, Ke; Peng, Junbiao; Cao, Yong; Liu, Feng; Russell, Thomas P; Peng, Xiaobin

2015-09-30

Solvent additive processing is important in optimizing an active layer's morphology and thus improving the performance of organic solar cells (OSCs). In this study, we find that how 1,8-diiodooctane (DIO) additive is removed plays a critical role in determining the film morphology of the bulk heterojunction OSCs in inverted structure based on a porphyrin small molecule. Different from the cases reported for polymer-based OSCs in conventional structures, the inverted OSCs upon the quick removal of the additive either by quick vacuuming or methanol washing exhibit poorer performance. In contrast, the devices after keeping the active layers in ambient pressure with additive dwelling for about 1 h (namely, additive annealing) show an enhanced power conversion efficiency up to 7.78% with a large short circuit current of 19.25 mA/cm(2), which are among the best in small molecule-based solar cells. The detailed morphology analyses using UV-vis absorption spectroscopy, grazing incidence X-ray diffraction, resonant soft X-ray scattering, and atomic force microscopy demonstrate that the active layer shows smaller-sized phase separation but improved structure order upon additive annealing. On the contrary, the quick removal of the additive either by quick vacuuming or methanol washing keeps the active layers in an earlier stage of large scaled phase separation.

Alkaline earth metal doped tin oxide as a novel oxygen storage material

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Qiang, E-mail: dong@tagen.tohoku.ac.jp; Yin, Shu; Yoshida, Mizuki

2015-09-15

Alkaline earth metal doped tin oxide (SnO{sub 2}) hollow nanospheres with a diameter of 50 nm have been synthesized successfully via a facial solvothermal route in a very simple system composed of only ethanol, acetic acid, SnCl{sub 4}·5H{sub 2}O and A(NO{sub 3}){sub 2}·xH{sub 2}O (A = Mg, Ca, Sr, Ba). The synthesized undoped SnO{sub 2} and A-doped SnO{sub 2} hollow nanospheres were characterized by the oxygen storage capacity (OSC), X-ray diffraction, transmission electron microscopy and the Brunauer–Emmet–Teller (BET) technique. The OSC values of all samples were measured using thermogravimetric-differential thermal analysis. The incorporation of alkaline earth metal ion into tinmore » oxide greatly enhanced the thermal stability and OSC. Especially, Ba-doped SnO{sub 2} hollow nanospheres calcined at 1000 °C for 20 h with a BET surface area of 61 m{sup 2} g{sup −1} exhibited the considerably high OSC of 457 μmol-O g{sup −1} and good thermal stability. Alkaline earth metal doped tin oxide has the potential to be a novel oxygen storage material.« less

A digital peer-to-peer learning platform for clinical skills development.

PubMed

Basnak, Jesse; Ortynski, Jennifer; Chow, Meghan; Nzekwu, Emeka

2017-02-01

Due to constraints in time and resources, medical curricula may not provide adequate opportunities for pre-clerkship students to practice clinical skills. To address this, medical students at the University of Alberta developed a digital peer-to-peer learning initiative. The initiative assessed if students can learn clinical skills from their peers in co-curricular practice objective structured clinical exams (OSCEs). A total of 144 first-year medical students participated. Students wrote case scenarios that were reviewed by physicians. Students enacted the cases in practice OSCEs, acting as the patient, physician, and evaluator. Verbal and electronic evaluations were completed. A digital platform was used to automate the process. Surveys were disseminated to assess student perceptions of their experience. Seventy-five percent of participants said they needed opportunities to practice patient histories and physical exams in addition to those provided in the medical school curriculum. All participants agreed that the co-curricular practice OSCEs met this need. The majority of participants also agreed that the digital platform was efficient and easy to use. Students found the practice OSCEs and digital platform effective for learning clinical skills. Thus, peer-to-peer learning and computer automation can be useful adjuncts to traditional medical curricula.

Outcome of parent-physician communication skills training for pediatric residents.

PubMed

Nikendei, Christoph; Bosse, Hans Martin; Hoffmann, Katja; Möltner, Andreas; Hancke, Rabea; Conrad, Corinna; Huwendiek, Soeren; Hoffmann, Georg F; Herzog, Wolfgang; Jünger, Jana; Schultz, Jobst-Hendrik

2011-01-01

communication skills represent an essential component of clinical competence. In the field of pediatrics, communication between physicians and patients' parents is characterized by particular difficulties. To investigate the effects of a parent-physician communication skills training program on OSCE performance and self-efficacy in a group control design. parallel to their daily work in the outpatient department, intervention-group experienced clinicians in practice (n=14) participated in a communication training with standardized parents. Control-group physicians (n=14) did not receive any training beyond their daily work. Performance was assessed by independent video ratings of an OSCE. Both groups rated their self-efficacy prior to and following training. regarding OSCE performance, the intervention group demonstrated superior skills in building relationships with parents (p<.024) and tended to perform better in exploring parents' problems (p<.081). The communication training program led to significant improvement in self-efficacy with respect to the specific training objectives in the intervention group (p<.046). even in physicians with considerable experience, structured communication training with standardized parents leads to significant improvement in OSCE performance and self-efficacy. PRACTISE IMPLICATIONS: briefness and tight structure make the presented communication training program applicable even for experienced physicians in daily clinical practice. 2010 Elsevier Ireland Ltd. All rights reserved.

Inverted Ultrathin Organic Solar Cells with a Quasi-Grating Structure for Efficient Carrier Collection and Dip-less Visible Optical Absorption.

PubMed

In, Sungjun; Park, Namkyoo

2016-02-23

We propose a metallic-particle-based two-dimensional quasi-grating structure for application to an organic solar cell. With the use of oblate spheroidal nanoparticles in contact with an anode of inverted, ultrathin organic solar cells (OSCs), the quasi-grating structure offers strong hybridization between localized surface plasmons and plasmonic gap modes leading to broadband (300~800 nm) and uniform (average ~90%) optical absorption spectra. Both strong optical enhancement in extreme confinement within the active layer (90 nm) and improved hole collection are thus realized. A coupled optical-electrical multi-physics optimization shows a large (~33%) enhancement in the optical absorption (corresponding to an absorption efficiency of ~47%, AM1.5G weighted, visible) when compared to a control OSC without the quasi-grating structure. That translates into a significant electrical performance gain of ~22% in short circuit current and ~15% in the power conversion efficiency (PCE), leading to an energy conversion efficiency (~6%) which is comparable to that of optically-thick inverted OSCs (3-7%). Detailed analysis on the influences of mode hybridization to optical field distributions, exciton generation rate, charge carrier collection efficiency and electrical conversion efficiency is provided, to offer an integrated understanding on the coupled optical-electrical optimization of ultrathin OSCs.

Effects of Job Burnout and Emotional Labor on Objective Structured Clinical Examination Performance Among Interns and Residents in Taiwan.

PubMed

Wang, Chen-Yu; Chen, Jen-De; Wang, Chih-Hung; Wang, Jong-Yi; Tai, Chih-Jaan; Hsieh, Tsu-Yi; Chen, Der-Yuan

2017-01-01

Medical education faces challenges concerning job burnout and emotional labor among junior physicians, which poses a potential threat to the quality of medical care. Although studies have investigated job burnout and emotional labor among physicians, empirical research on the association between job burnout, emotional labor, and clinical performance is lacking. This study investigated the effects of job burnout and emotional labor on clinical performance by using the objective structured clinical examination (OSCE) scores of interns and residents. Specifically, this cross-sectional study utilized the Maslach Burnout Inventory and the Emotional Labor Questionnaire as measurement instruments. A total of 225 interns and residents in central Taiwan answered structured questionnaires before beginning their OSCE. The major statistical analysis method employed was logistic regression. After adjustment for covariates, first-year residents were less likely than other residents to obtain high OSCE scores. The odds of high OSCE performance among interns and residents with high interaction component scores in emotional labor were significantly higher than those with low interaction scores. A high score in the interaction dimension of emotional labor was associated with strong clinical performance. The findings suggest that interventions which motivate positive attitudes and increase interpersonal interaction skills among physicians should receive higher priority.

Ternary Organic Solar Cells Based on Two Compatible Nonfullerene Acceptors with Power Conversion Efficiency >10.

PubMed

Liu, Tao; Guo, Yuan; Yi, Yuanping; Huo, Lijun; Xue, Xiaonan; Sun, Xiaobo; Fu, Huiting; Xiong, Wentao; Meng, Dong; Wang, Zhaohui; Liu, Feng; Russell, Thomas P; Sun, Yanming

2016-12-01

Two different nonfullerene acceptors and one copolymer are used to fabricate ternary organic solar cells (OSCs). The two acceptors show unique interactions that reduce crystallinity and form a homogeneous mixed phase in the blend film, leading to a high efficiency of ≈10.3%, the highest performance reported for nonfullerene ternary blends. This work provides a new approach to fabricate high-performance OSCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functional Flow and Event-Driven Methods for Predicting System Performance

DTIC Science & Technology

2015-09-01

The thesis process was difficult and at times painful , but the modeling applications were something that I thoroughly enjoyed working through and...21. 2. SAR Mission initiates; SAR Assets conduct search but no objects of interest are found; SAR assets continue to scan but OSC aborts mission...be related to the SAR, so the OSC aborts mission and all Assets RTB. 45 4. SAR Mission initiates; SAR Assets conduct search and find an object of

Model-Based Systems Engineering in the Execution of Search and Rescue Operations

DTIC Science & Technology

2015-09-01

OSC can fulfill the duties of an ACO but it may make sense to split the duties if there are no communication links between the OSC and participating...parallel mode. This mode is the most powerful option because it 35 creates sequence diagrams that generate parallel “ swim lanes” for each asset...greater flexibility is desired, sequence mode generates diagrams based purely on sequential action and activity diagrams without the parallel “ swim lanes

Innovative Techniques to Predict Atmospheric Effects on Sensor Performance

DTIC Science & Technology

2009-10-15

since acquiring the MRO data, extensive tabulation of all of the data from all visible satellites (generally, non- resolved ) was also accomplished...efficient code has been written to run multiple OSC simulations in less time . Data from many passes of the same satellite is useful for SOI, whether it is...the data analyzed. Questions about the data were resolved using OSC to determine solar phase angle (SPA), range, time of penumbra entrance/exit and

Final year MBBS students' perception for observed structured clinical examination.

PubMed

Siddiqui, Faisal Ghani

2013-01-01

To determine perceptions of final year students about observed structured clinical examination (OSCE) and to determine its acceptance among these students. Sequential mixed method design using survey questionnair and in-depth interviews. The study constituted a one-time survey and in-depth interviews conducted over a period of three consecutive days during final year MBBS annual examination at OSCE centre, from April 04, 2010 to April 06, 2010. Three hundred and fifty final year MBBS students, selected through non-probability convenience sampling, were asked to fill the 12-item questionnaire. Three hundred and thirty one students returned the forms. In-depth, structured interviews with 22 students, selected by non-probability purposive sampling, were conducted. The interviews were tape recorded for subsequent transcription. The statistical analysis was done using SPSS 17. The qualitative data was analyzed through content analysis techniques. Three hundred and thirty one final year MBBS students (50.6% females) filled the questionnaire (response rate 94.6%). Fifty three percent respondents agreed that the OSCE tasks were taught during clinical rotations. The experience was stressful for 67.9% respondents. Inadequate prior guidelines, inadequate time for stations, newness of the assessment format and vague instructions were the main causes for stress. Over 70% of the students felt that OSCE helped them identify areas of weakness in their practical and clinical skills; 56.5% felt that the stations dealt with practical skills. Seventy nine percent students were happy with the attitude of the examiners while 19% students felt that the facilitators were uncooperative; failure of the examiners to observe the students during performance of the tasks was the major cause for dissatisfaction. Nearly thirty percent (29.9%) respondent felt that the stations were difficult to understand. Over forty nine percent (49.7%) complained that adequate guidelines were not given prior to

The impact of outpatient clinical teaching on students' academic performance in obstetrics and gynecology.

PubMed

Hassan, Bahaeldin A; Elfaki, Omer A; Khan, Muhammed A

2017-01-01

Clinical teaching at outpatient settings is an essential part of undergraduate medical students' training. The increasing number of students in many medical schools and short hospital stays makes inpatient teaching alone insufficient to provide students with the required clinical skills. To make up this shortfall, outpatient clinical teaching has been implemented by our Department of Obstetrics and Gynecology, King Khalid University, KSA, throughout the academic year 2015-2016. The aim of this study was to evaluate the impact of clinical teaching at outpatient settings on the academic performance of our students. In this comparative retrospective study, the effects of outpatient clinical teaching of obstetrics and gynecology on the academic performance of student was assessed through an objective structured clinical examination (OSCE). During their course on obstetrics and gynecology, 58 students had their clinical teaching both at inpatient and outpatient settings and constituted "study group". The remaining 52 students had clinical teaching only at inpatient settings and were considered "control group". Students in both groups sat for OSCE at the end of week 8 of the gynecology course. Students in both groups sat for OSCE at the end of week 8 of the gynecology course. Four stations were used for assessment: obstetric history, gynecological history, obstetric physical examination of pregnant women, and gynecological procedure station. Twenty marks were allocated for each station giving a total score of 80. The OSCE scores for study group were compared with those of the control group using Student's t -test; p < 0.05 was considered statistically significant. The total mean OSCE score was statistically significantly higher in the study group (62.36 vs. 47.94, p < 0.001). The study group participants showed significantly higher scores in the gynecological procedure station (16.74 vs. 11.62, p < 0.0001) and obstetric examination station (16.72 vs. 10.79, p < 0

Feedback Implementation of Zermelo's Optimal Control by Sugeno Approximation

NASA Technical Reports Server (NTRS)

Clifton, C.; Homaifax, A.; Bikdash, M.

1997-01-01

This paper proposes an approach to implement optimal control laws of nonlinear systems in real time. Our methodology does not require solving two-point boundary value problems online and may not require it off-line either. The optimal control law is learned using the original Sugeno controller (OSC) from a family of optimal trajectories. We compare the trajectories generated by the OSC and the trajectories yielded by the optimal feedback control law when applied to Zermelo's ship steering problem.

Developing plans and priorities for climate science in service to society

NASA Astrophysics Data System (ADS)

Asrar, Ghassem; Busalacchi, Antonio; Hurrell, James

2012-03-01

World Climate Research Programme (WCRP) Open Science Conference; Denver, Colorado, 24-28 October 2011 The WCRP Open Science Conference (OSC), which had the theme "Climate Research in Service to Society," was held to consult with the international community of experts on future plans and priorities for the WCRP. More than 1900 participants, including 541 young scholars from 86 nations and 300 scientists from developing nations, made the conference a success. Several major scientific priorities emerged from OSC.

Interface design principles for high-performance organic semiconductor devices

DOE PAGES

Nie, Wanyi; Gupta, Gautam; Crone, Brian K.; ...

2015-03-23

Organic solar cells (OSCs) are a promising cost-effective candidate in next generation photovoltaic technology. However, a critical bottleneck for OSCs is the electron/hole recombination loss through charge transfer state at the interface, which greatly limits the power conversion efficiency. W. Nie, A. Mohite, and co-workers demonstrate a simple strategy of suppressing the recombination rate by inserting a spacer layer at the donor-acceptor interface, resulting in a dramatic increase in power conversion efficiency.

High-performance ternary blend polymer solar cells involving both energy transfer and hole relay processes.

PubMed

Lu, Luyao; Chen, Wei; Xu, Tao; Yu, Luping

2015-06-04

The integration of multiple materials with complementary absorptions into a single junction device is regarded as an efficient way to enhance the power conversion efficiency (PCE) of organic solar cells (OSCs). However, because of increased complexity with one more component, only limited high-performance ternary systems have been demonstrated previously. Here we report an efficient ternary blend OSC with a PCE of 9.2%. We show that the third component can reduce surface trap densities in the ternary blend. Detailed studies unravel that the improved performance results from synergistic effects of enlarged open circuit voltage, suppressed trap-assisted recombination, enhanced light absorption, increased hole extraction, efficient energy transfer and better morphology. The working mechanism and high device performance demonstrate new insights and design guidelines for high-performance ternary blend solar cells and suggest that ternary structure is a promising platform to boost the efficiency of OSCs.

Highly-stable and -flexible graphene/(CF3SO2)2NH/graphene transparent conductive electrodes for organic solar cells

NASA Astrophysics Data System (ADS)

Seo, Sang Woo; Lee, Ha Seung; Shin, Dong Hee; Kim, Ju Hwan; Jang, Chan Wook; Kim, Jong Min; Kim, Sung; Choi, Suk-Ho

2017-10-01

We first employ highly-stable and -flexible (CF3SO2)2NH-doped graphene (TFSA/GR) and GR-encapsulated TFSA/GR (GR/TFSA/GR) transparent conductive electrodes (TCEs) prepared on polyethylene terephthalate substrates for flexible organic solar cells (OSCs). Compared to conventional indium tin oxide (ITO) TCEs, the TFSA-doped-GR TCEs show higher optical transmittance and larger sheet resistance. The TFSA/GR and GR/TFSA/GR TCEs show work functions of 4.89 ± 0.16 and 4.97 ± 0.18 eV, respectively, which are not only larger than those of the ITO TCEs but also indicate p-type doping of GR, and are therefore more suitable for anode TCEs of OSCs. In addition, typical GR/TFSA/GR-TCE OSCs are much more mechanically flexible than the ITO-TCE ones with their photovoltaic parameters being similar, as proved by bending tests as functions of cycle and curvature.

Assessment of pharmacy students' communication competence using the Roter Interaction Analysis System during objective structured clinical examinations.

PubMed

Kubota, Yoshie; Yano, Yoshitaka; Seki, Susumu; Takada, Kaori; Sakuma, Mio; Morimoto, Takeshi; Akaike, Akinori; Hiraide, Atsushi

2011-04-11

To determine the value of using the Roter Interaction Analysis System during objective structured clinical examinations (OSCEs) to assess pharmacy students' communication competence. As pharmacy students completed a clinical OSCE involving an interview with a simulated patient, 3 experts used a global rating scale to assess students' overall performance in the interview, and both the student's and patient's languages were coded using the Roter Interaction Analysis System (RIAS). The coders recorded the number of utterances (ie, units of spoken language) in each RIAS category. Correlations between the raters' scores and the number and types of utterances were examined. There was a significant correlation between students' global rating scores on the OSCE and the number of utterances in the RIAS socio-emotional category but not the RIAS business category. The RIAS proved to be a useful tool for assessing the socio-emotional aspect of students' interview skills.

Effect of organic small-molecule hole injection materials on the performance of inverted organic solar cells

NASA Astrophysics Data System (ADS)

Li, Jie; Zheng, Yifan; Zheng, Ding; Yu, Junsheng

2016-07-01

In this study, the influence of small-molecule organic hole injection materials on the performance of organic solar cells (OSCs) as the hole transport layer (HTL) with an architecture of ITO/ZnO/P3HT:PC71BM/HTL/Ag has been investigated. A significant enhancement on the performance of OSCs from 1.06% to 2.63% is obtained by using N, N‧-bis(1-naphthalenyl)-N, N‧-bis-phenyl-(1, 1‧-biphenyl)-4, 4‧-diamine (NPB) HTL. Through the resistance simulation and space-charge limited current analysis, we found that NPB HTL cannot merely improve the hole mobility of the device but also form the Ohmic contact between the active layer and anode. Besides, when we apply mix HTL by depositing the NPB on the surface of molybdenum oxide, the power conversion efficiency of OSC are able to be further improved to 2.96%.

Use of DEAD-box polypeptide-4 (Ddx4) gene promoter-driven fluorescent reporter mice to identify mitotically active germ cells in post-natal mouse ovaries

PubMed Central

Park, Eun-Sil; Tilly, Jonathan L.

2015-01-01

Several laboratories have independently isolated mitotically active germ cells, termed female germline stem cells or oogonial stem cells (OSCs), from adult mouse ovaries. However, a recent study using Ddx4-Cre;Rosa26 reporter mice concluded that such germ cells do not exist. Given the disparity in conclusions drawn in this study compared with others, we felt it was important to re-assess the utility of Ddx4-Cre;Rosa26 reporter mice for identification of OSCs in adult mouse ovaries. Transgenic Ddx4-Cre mice were crossed with Rosa26tdTm/tdTm mice to drive restricted tomato red (tdTm) gene expression in cells in which the Ddx4 gene promoter has been activated. Crude dispersion of ovaries from recombined offspring generated cell fractions containing tdTm-positive immature oocytes, which are incapable of proliferation and thus probably represent the uncharacterized reporter-positive ovarian cells identified in the paper Zhang et al. (2012) as being mitotically inactive. Dispersed ovaries further subjected to fluorescence-activated cell sorting yielded a large population of non-germline tdTm-positive cells, indicative of promoter ‘leakiness’ in the Ddx4-Cre mouse line. Nonetheless, a small percentage of these tdTm-positive cells exhibited externalized (extracellular, ec) expression of Ddx4 protein (ecDdx4-positive), expressed markers of primitive germ cells but not of oocytes, and actively proliferated in culture, all of which are characteristic features of OSCs. Thus, crude dispersion of ovaries collected from Ddx4 gene promoter-driven reporter mice is not, by itself, a reliable approach to identify OSCs, whereas the same ovarian dispersates further subjected to cell sorting strategies yield purified OSCs that can be expanded in culture. PMID:25147160

E-learning module on chronic low back pain in older adults: evidence of effect on medical student objective structured clinical examination performance.

PubMed

Weiner, Debra K; Morone, Natalia E; Spallek, Heiko; Karp, Jordan F; Schneider, Michael; Washburn, Carol; Dziabiak, Michael P; Hennon, John G; Elnicki, D Michael

2014-06-01

The Institute of Medicine has highlighted the urgent need to close undergraduate and graduate educational gaps in treating pain. Chronic low back pain (CLBP) is one of the most common pain conditions, and older adults are particularly vulnerable to potential morbidities associated with misinformed treatment. An e-learning case-based interactive module was developed at the University of Pittsburgh Center of Excellence in Pain Education, one of 12 National Institutes of Health-designated centers, to teach students important principles for evaluating and managing CLBP in older adults. A team of six experts in education, information technology, pain management, and geriatrics developed the module. Teaching focused on common errors, interactivity, and expert modeling and feedback. The module mimicked a patient encounter using a standardized patient (the older adult with CLBP) and a pain expert (the patient provider). Twenty-eight medical students were not exposed to the module (Group 1) and 27 were exposed (Group 2). Their clinical skills in evaluating CLBP were assessed using an objective structured clinical examination (OSCE). Mean scores were 62.0 ± 8.6 for Group 1 and 79.5 ± 10.4 for Group 2 (P < .001). Using an OSCE pass-fail cutoff score of 60%, 17 of 28 Group 1 students (60.7%) and 26 of 27 Group 2 students (96.3%) passed. The CLBP OSCE was one of 10 OSCE stations in which students were tested at the end of a Combined Ambulatory Medicine and Pediatrics Clerkship. There were no between-group differences in performance on eight of the other nine OSCE stations. This module significantly improved medical student clinical skills in evaluating CLBP. Additional research is needed to ascertain the effect of e-learning modules on more-advanced learners and on improving the care of older adults with CLBP. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

E-Learning Module on Chronic Low Back Pain in Older Adults: Evidence of Effect on Medical Student Objective Structured Clinical Examination Performance

PubMed Central

Weiner, Debra K.; Morone, Natalia E.; Spallek, Heiko; Karp, Jordan F.; Schneider, Michael; Washburn, Carol; Dziabiak, Michael P.; Hennon, John G.; Elnicki, D. Michael

2015-01-01

The Institute of Medicine has highlighted the urgent need to close undergraduate and graduate educational gaps in treating pain. Chronic low back pain (CLBP) is one of the most common pain conditions, and older adults are particularly vulnerable to potential morbidities associated with misinformed treatment. An e-learning case-based interactive module was developed at the University of Pittsburgh Center of Excellence in Pain Education, one of 12 National Institutes of Health–designated centers, to teach students important principles for evaluating and managing CLBP in older adults. A team of six experts in education, information technology, pain management, and geriatrics developed the module. Teaching focused on common errors, interactivity, and expert modeling and feedback. The module mimicked a patient encounter using a standardized patient (the older adult with CLBP) and a pain expert (the patient provider). Twenty-eight medical students were not exposed to the module (Group 1) and 27 were exposed (Group 2). Their clinical skills in evaluating CLBP were assessed using an objective structured clinical examination (OSCE). Mean scores were 62.0 ± 8.6 for Group 1 and 79.5 ± 10.4 for Group 2 (P < .001). Using an OSCE pass–fail cutoff score of 60%, 17 of 28 Group 1 students (60.7%) and 26 of 27 Group 2 students (96.3%) passed. The CLBP OSCE was one of 10 OSCE stations in which students were tested at the end of a Combined Ambulatory Medicine and Pediatrics Clerkship. There were no between-group differences in performance on eight of the other nine OSCE stations. This module significantly improved medical student clinical skills in evaluating CLBP. Additional research is needed to ascertain the effect of e-learning modules on more-advanced learners and on improving the care of older adults with CLBP. PMID:24833496

S100A8, An Oocyte-Specific Chemokine, Directs the Migration of Ovarian Somatic Cells During Mouse Primordial Follicle Assembly.

PubMed

Teng, Zhen; Wang, Chao; Wang, Yijing; Huang, Kun; Xiang, Xi; Niu, Wanbao; Feng, Lizhao; Zhao, Lihua; Yan, Hao; Zhang, Hua; Xia, Guoliang

2015-12-01

In the mammalian ovaries, the primordial follicle pool determines the reproductive capability over the lifetime of a female. The primordial follicle is composed of two cell members, namely the oocyte and the pre-granulosa cells that encircle the oocyte. However, it is unclear what factors are involved in the reorganization of the two distinct cells into one functional unit. This study was performed to address this issue. Firstly, in an in vitro reconstruction system, dispersed ovarian cells from murine fetal ovaries at 19.0 days post coitum (dpc) reassembled into follicle-like structures, independent of the physical distance between the cells, implying that either oocytes or ovarian somatic cells (OSCs) were motile. We then carried out a series of transwell assay experiments, and determined that it was in fact 19.0 dpc OSCs (as opposed to oocytes), which exhibited a significant chemotactic response to both fetal bovine serum and oocytes themselves. We observed that S100A8, a multi-functional chemokine, may participate in the process as it is mainly expressed in oocytes within the cysts/plasmodia. S100A8 significantly promoted the number of migrating OSCs by 2.5 times in vitro, of which 66.9% were FOXL2 protein-positive cells, implying that the majority of motile OSCs were pre-granulosa cells. In addition, an S100A8-specific antibody inhibited the formation of follicle-like reconstruction cell mass in vitro. And, the primordial follicle formation was reduced when S100a8-specific siRNA was applied onto in vitro cultured 17.5 dpc ovary. Therefore, S100A8 could be a chemokine of oocyte origin, which attracts OSCs to form the primordial follicles. © 2015 Wiley Periodicals, Inc.

An objective structured clinical exam to measure intrinsic CanMEDS roles.

PubMed

Kassam, Aliya; Cowan, Michèle; Donnon, Tyrone

2016-01-01

Background The CanMEDS roles provide a comprehensive framework to organize competency-based curricula; however, there is a challenge in finding feasible, valid, and reliable assessment methods to measure intrinsic roles such as Communicator and Collaborator. The objective structured clinical exam (OSCE) is more commonly used in postgraduate medical education for the assessment of clinical skills beyond medical expertise. Method We developed the CanMEDS In-Training Exam (CITE), a six-station OSCE designed to assess two different CanMEDS roles (one primary and one secondary) and general communication skills at each station. Correlation coefficients were computed for CanMEDS roles within and between stations, and for general communication, global rating, and total scores. One-way analysis of variance (ANOVA) was used to investigate differences between year of residency, sex, and the type of residency program. Results In total, 63 residents participated in the CITE; 40 residents (63%) were from internal medicine programs, whereas the remaining 23 (37%) were pursuing other specialties. There was satisfactory internal consistency for all stations, and the total scores of the stations were strongly correlated with the global scores r=0.86, p<0.05. Noninternal medicine residents scored higher in terms of the Professional competency overall, whereas internal medicine residents scored significantly higher in the Collaborator competency overall. Discussion The OSCE checklists developed for the assessment of intrinsic CanMEDS roles were functional, but the specific items within stations required more uniformity to be used between stations. More generic types of checklists may also improve correlations across stations. Conclusion An OSCE measuring intrinsic competence is feasible; however, further development of our cases and checklists is needed. We provide a model of how to develop an OSCE to measure intrinsic CanMEDS roles that educators may adopt as residency programs move

Criterion validity of a competency-based assessment center in medical education--a 4-year follow-up study.

PubMed

Rotthoff, Thomas; Ostapczuk, Martin S; Kröncke, Klaus D; Zimmerhofer, Alexander; Decking, Ulrich; Schneider, Matthias; Ritz-Timme, Stefanie

2014-01-01

Core competencies have progressively gained importance in medical education. In other contexts, especially personnel selection and development, assessment centers (ACs) are used to assess competencies, but there is only a limited number of studies on competency-based ACs in medical education. To the best of our knowledge, the present study provides the first data on the criterion-related validity of a competency-based AC in medical education. We developed an AC tailored to measure core competencies relevant to medical education (social-ethical, communicative, self, and teaching) and tested its validity in n=30 first-year medical students using 3- to 4-year follow-up measures such as (a) objective structured clinical examinations (OSCE) on basic clinical skills (n=26), (b) OSCE on communication skills (n=21), and (c) peer feedback (n=18). The AC contained three elements: interview, group discussion, and role play. Additionally, a self-report questionnaire was provided as a basis for the interview. Baseline AC average score and teaching competency correlated moderately with the communication OSCE average score (r=0.41, p=0.03, and r=0.38, p=0.04, respectively). Social-ethical competency in the AC showed a very strong convergent association with the communication OSCE average score (r=0.60, p<0.01). The AC total score also showed a moderate correlation with the overall peer feedback score provided in Year 4 (r=0.38, p=0.06). In addition, communicative competency correlated strongly with the overall peer feedback (r=0.50, p=0.02). We found predominantly low and insignificant correlations between the AC and the OSCE on basic clinical skills (r=-0.33 to 0.30, all p's>0.05). The results showed that competency-based ACs can be used at a very early stage of medical training to successfully predict future performance in core competencies.

Criterion validity of a competency-based assessment center in medical education - a 4-year follow-up study.

PubMed

Rotthoff, Thomas; Ostapczuk, Martin S; Kröncke, Klaus D; Zimmerhofer, Alexander; Decking, Ulrich; Schneider, Matthias; Ritz-Timme, Stefanie

2014-01-01

Introduction Core competencies have progressively gained importance in medical education. In other contexts, especially personnel selection and development, assessment centers (ACs) are used to assess competencies, but there is only a limited number of studies on competency-based ACs in medical education. To the best of our knowledge, the present study provides the first data on the criterion-related validity of a competency-based AC in medical education. Methods We developed an AC tailored to measure core competencies relevant to medical education (social-ethical, communicative, self, and teaching) and tested its validity in n=30 first-year medical students using 3- to 4-year follow-up measures such as (a) objective structured clinical examinations (OSCE) on basic clinical skills (n=26), (b) OSCE on communication skills (n=21), and (c) peer feedback (n=18). The AC contained three elements: interview, group discussion, and role play. Additionally, a self-report questionnaire was provided as a basis for the interview. Results Baseline AC average score and teaching competency correlated moderately with the communication OSCE average score (r=0.41, p=0.03, and r=0.38, p=0.04, respectively). Social-ethical competency in the AC showed a very strong convergent association with the communication OSCE average score (r=0.60, p<0.01). The AC total score also showed a moderate correlation with the overall peer feedback score provided in Year 4 (r=0.38, p=0.06). In addition, communicative competency correlated strongly with the overall peer feedback (r=0.50, p=0.02). We found predominantly low and insignificant correlations between the AC and the OSCE on basic clinical skills (r=-0.33 to 0.30, all p's>0.05). Conclusion The results showed that competency-based ACs can be used at a very early stage of medical training to successfully predict future performance in core competencies.

The subcellular distribution of aquaporin 5 in the cochlea reveals a water shunt at the perilymph-endolymph barrier.

PubMed

Hirt, B; Penkova, Z H; Eckhard, A; Liu, W; Rask-Andersen, H; Müller, M; Löwenheim, H

2010-07-28

Aquaporins are membrane water channel proteins that have also been identified in the cochlea. Auditory function critically depends on the homeostasis of the cochlear fluids perilymph and endolymph. In particular, the ion and water regulation of the endolymph is essential for sensory transduction. Within the cochlear duct the lateral wall epithelium has been proposed to secrete endolymph by an aquaporin-mediated flow of water across its epithelial tight junction barrier. This study identifies interspecies differences in the cellular distribution of aquaporin 5 (AQP5) in the cochlear lateral wall of mice, rats, gerbils and guinea pigs. In addition the cellular expression pattern of AQP5 is described in the human cochlea. Developmental changes in rats demonstrate longitudinal and radial gradients along the cochlear duct. During early postnatal development a pancochlear expression is detected. However a regression to the apical quadrant and limitation to outer sulcus cells (OSCs) is observed in the adult. This developmental loss of AQP5 expression in the basal cochlear segments coincides with a morphological loss of contact between OSCs and the endolymph. At the subcellular level, AQP5 exhibits polarized expression in the apical plasma membrane of the OSCs. Complementary, the basolateral membrane in the root processes of the OSCs exhibits AQP4 expression. This differential localization of AQP5 and AQP4 in the apical and basolateral membranes of the same epithelial cell type suggests a direct aquaporin-mediated transcellular water shunt between the perilymph and endolymph in the OSCs of the cochlear lateral wall. In the human cochlea these findings may have pathophysiological implications attributed to a dysfunctional water regulation by AQP5 such as endolymphatic hydrops (i.e. in Meniere's disease) or sensorineural hearing loss (i.e. in Sjögren's syndrome). Copyright (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Space closing versus space opening for bilateral missing upper laterals - aesthetic judgments of laypeople: a web-based survey.

PubMed

Qadri, Salim; Parkin, Nicola A; Benson, Philip E

2016-06-01

To investigate the opinions of laypeople regarding the aesthetic outcome of treating patients with developmental absence of both maxillary lateral incisors using either orthodontic space closure (OSC) or space opening and prosthetic replacement (PR). Cross sectional, web-based survey. A panel of five orthodontists and five restorative dentists examined post-treatment intra-oral images of 21 patients with developmental absence of both upper lateral incisors. A consensus view was obtained about the 10 most attractive images (5 OSC; 5 PR). The 10 selected images were used in a web-based survey involving staff and students at the University of Sheffield. In the first section, the participants were asked to evaluate the attractiveness of the 10 randomly arranged single images using a 5-point Likert scale. In the second section, an image of OSC was paired with an image of PR according to their attractiveness ranking by the clinician panel, and the participants were asked to indicate which of the two images they preferred. The survey received 959 completed responses with 9590 judgements. The images of OSC were perceived to be more attractive (mean rating 3·34 out of 5; SD 0·56) compared with the images of PR (mean rating 3·14 out of 5; SD 0·58) (mean diff 0·21; P < 0·001). Female and staff judges tended to give higher attractiveness ratings. Both females and males preferred the OSC images closing in 3 out of 4 paired images. Space closing was perceived to be more attractive than space opening by lay people. The findings have implications for advising patients about the best aesthetic outcome when both maxillary lateral incisors are missing.

Disruptive behavior in the workplace: Challenges for gastroenterology fellows.

PubMed

Srisarajivakul, Nalinee; Lucero, Catherine; Wang, Xiao-Jing; Poles, Michael; Gillespie, Colleen; Zabar, Sondra; Weinshel, Elizabeth; Malter, Lisa

2017-05-14

To assess first-year gastroenterology fellows' ability to address difficult interpersonal situations in the workplace using objective structured clinical examinations (OSCE). Two OSCEs ("distracted care team" and "frazzled intern") were created to assess response to disruptive behavior. In case 1, a fellow used a colonoscopy simulator while interacting with a standardized patient (SP), nurse, and attending physician all played by actors. The nurse and attending were instructed to display specific disruptive behavior and disregard the fellow unless requested to stop the disruptive behavior and focus on the patient and procedure. In case 2, the fellow was to calm an intern managing a patient with massive gastrointestinal bleeding. The objective in both scenarios was to assess the fellows' ability to perform their duties while managing the disruptive behavior displayed by the actor. The SPs used checklists to rate fellows' performances. The fellows completed a self-assessment survey. Twelve fellows from four gastrointestinal fellowship training programs participated in the OSCE. In the "distracted care team" case, one-third of the fellows interrupted the conflict and refocused attention to the patient. Half of the fellows were able to display professionalism despite the heated discussion nearby. Fellows scored lowest in the interprofessionalism portion of post-OSCE surveys, measuring their ability to handle the conflict. In the "frazzled intern" case, 68% of fellows were able to establish a calm and professional relationship with the SP. Despite this success, only half of the fellows were successfully communicate a plan to the SP and only a third scored "well done" in a domain that focused on allowing the intern to think through the case with the fellow's guidance. Fellows must receive training on how to approach disruptive behavior. OSCEs are a tool that can assess fellow skills and set a culture for open discussion.

Open standing castration in Thoroughbred racehorses in Hong Kong: Prevalence and severity of complications 30 days post-castration.

PubMed

Rosanowski, S M; MacEoin, F; Graham, R J T Y; Riggs, C M

2018-05-01

Complications following open standing castration (OSC) in Thoroughbred racehorses are well recognised but variation in their prevalence and severity between populations is not well documented. To describe the prevalence and severity of complications in the 30 days following OSC. A retrospective cohort study of veterinary clinical records relating to horses that underwent OSC between July 2007 and July 2012. Complications were graded on a severity score from N, no complications, to C3, severe complications. Additional data were accessed for each horse including age, import date, racing history, trainer and veterinarian performing the castration. Bacterial culture and antimicrobial sensitivities were performed on a limited number of castration wounds that became infected. In total, 250 horses were castrated in Hong Kong using the OSC technique over the period of the study. Sixty percent (150/250) of horses experienced some type of post-castration complication, with eight horses experiencing a severe (C3) complication requiring intensive veterinary treatment. Scrotal swelling, funiculitis and seroma formation were present in 70.0%, 36.7% and 24.7% of cases respectively. Most horses experiencing complications required wound reopening (87.3%; 131/150), and/or an extended course of first-line antimicrobials and/or nonsteroidal anti-inflammatory drugs (75/150; 50.0%). Eight horses had cultures submitted for bacterial sensitivity, with 17 bacterial isolates grown. In vitro, the bacteria cultured were sensitive to enrofloxacin (76%; 13/17) and ceftiofur (100%; 17/17). Resistance was detected to penicillin, gentamicin, oxytetracycline, metronidazole and trimethoprim-sulfadiazine. Differences in post-castration management cannot be accounted for in this study. Complications following OSC in horses in Hong Kong were common. The majority were mild and were successfully treated using antimicrobials and simple wound management. Given the high rate of complications and

Emulsion-Based RIR-MAPLE Deposition of Conjugated Polymers: Primary Solvent Effect and Its Implications on Organic Solar Cell Performance.

PubMed

Ge, Wangyao; Li, Nan K; McCormick, Ryan D; Lichtenberg, Eli; Yingling, Yaroslava G; Stiff-Roberts, Adrienne D

2016-08-03

Emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) has been demonstrated as an alternative technique to deposit conjugated polymer films for photovoltaic applications; yet, a fundamental understanding of how the emulsion target characteristics translate into film properties and solar cell performance is unclear. Such understanding is crucial to enable the rational improvement of organic solar cell (OSC) efficiency and to realize the expected advantages of emulsion-based RIR-MAPLE for OSC fabrication. In this paper, the effect of the primary solvent used in the emulsion target is studied, both experimentally and theoretically, and it is found to determine the conjugated polymer cluster size in the emulsion as well as surface roughness and internal morphology of resulting polymer films. By using a primary solvent with low solubility-in-water and low vapor pressure, the surface roughness of deposited P3HT and PCPDTBT polymer films was reduced to 10 nm, and the efficiency of P3HT:PC61BM OSCs was increased to 3.2% (∼100 times higher compared to the first MAPLE OSC demonstration [ Caricato , A. P. ; Appl. Phys. Lett. 2012 , 100 , 073306 ]). This work unveils the mechanism of polymer film formation using emulsion-based RIR-MAPLE and provides insight and direction to determine the best ways to take advantage of the emulsion target approach to control film properties for different applications.

Resuscitation skills after Helping Babies Breathe training: a comparison of varying practice frequency and impact on retention of skills in different types of providers.

PubMed

Tabangin, M E; Josyula, S; Taylor, K K; Vasquez, J C; Kamath-Rayne, B D

2018-05-01

Helping Babies Breathe (HBB), a basic neonatal resuscitation curriculum, improves early neonatal mortality in low-resource settings. Our goal was to determine retention of resuscitation skills by different cadres of providers using the approved HBB Spanish translation in a rural clinic and community hospital in Honduras. Twelve clinic and 37 hospital providers were trained in 1 d HBB workshops and followed from July 2012 to February 2014. Resuscitation skills were evaluated by objective structured clinical evaluations (OSCEs) at regular intervals. Clinic providers practiced monthly, whereas hospital providers were randomized to monthly practice for 6 months vs three consecutive practices at 3, 5 and 6 months. In the rural clinic, follow-up OSCE assessment showed rapid loss of skills by 1 month after HBB training. For all providers, repeated monthly testing resulted in improvements and maintenance of OSCE performance. In the community hospital, over all time points, the group with monthly OSCEs had 2.9 greater odds of passing compared with the group who practiced less frequently. Physicians were found to have 4.3 times greater odds of passing compared with nurses. Rapid loss of resuscitation skills occurs after an initial training. Repeated practice leads to retention of skills in all types of providers. Further investigation is warranted to determine the clinical correlation of neonatal outcomes after HBB training.

Jet Formation and Penetration Study of Double-Layer Shaped Charge

NASA Astrophysics Data System (ADS)

Wang, Zhe; Jiang, Jian-Wei; Wang, Shu-You; Liu, Han

2018-04-01

A theoretical analysis on detonation wave propagation in a double-layer shaped charge (DLSC) is performed. Numerical simulations using the AUTODYN software are carried out to compare the distinctions between jet formations in DLSC and ordinary shaped charge (OSC), in particular, the OSC made using a higher detonation velocity explosive, which is treated as the outer layer charge in the DLSC. The results show that the improved detonation velocity ratio and radial charge percentage of outer-to-inner layer charge are conducive to the formation of a convergent detonation wave, which contributes to enhancement of jet tip velocity in DLSC. The thickness and mass percentages of liner flowing into jet in DLSC closely follow the exponential distribution along the radial direction, but the percentages in DLSC and the mass of effective jet, which have significant influence on the penetration depth, are lower than those in OSC with the outer layer charge. This implies that the total charge energy is the major factor controlling the effective jet formation, which is confirmed by the verification tests using flash X-ray system and following penetration tests. The numerical simulation and test results compare well, while penetration test results indicate that the performance of DLSC is not better than that of OSC with the outer layer charge, due to the differences in jet formation.

Objective Structured Clinical Examination as an Assessment Tool for Clinical Skills in Dermatology.

PubMed

Saceda-Corralo, D; Fonda-Pascual, P; Moreno-Arrones, Ó M; Alegre-Sánchez, A; Hermosa-Gelbard, Á; Jiménez-Gómez, N; Vañó-Galván, S; Jaén-Olasolo, P

2017-04-01

Objective Structured Clinical Evaluation (OSCE) is an excellent method to evaluate student's abilities, but there are no previous reports implementing it in dermatology. To determine the feasibility of implementation of a dermatology OSCE in the medical school. Five stations with standardized patients and image-based assessment were designed. A specific checklist was elaborated in each station with different items which evaluated one competency and were classified into five groups (medical history, physical examination, technical skills, case management and prevention). A total of 28 students were tested. Twenty-five of them (83.3%) passed the exam globally. Concerning each group of items tested: medical interrogation had a mean score of 71.0; physical examination had a mean score of 63.0; management had a mean score of 58.0; and prevention had a mean score of 58.0 points. The highest results were obtained in interpersonal skills items with 91.8 points. Testing a small sample of voluntary students may hinder generalization of our study. OSCE is an useful tool for assessing clinical skills in dermatology and it is possible to carry it out. Our experience enhances that medical school curriculum needs to establish OSCE as an assessment tool in dermatology. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

Can professionalism be taught? Encouraging evidence.

PubMed

Hochberg, Mark S; Kalet, Adina; Zabar, Sondra; Kachur, Elizabeth; Gillespie, Colleen; Berman, Russell S

2010-01-01

Teaching and assessing the Accreditation Council for Graduate Medical Education (ACGME) competencies of Professionalism and Communication have proven to be a challenge for surgical residency training programs. This study used innovative pedagogic approaches and tools in teaching these two competencies. The purpose of this study was to determine whether the learners actually are assimilating and using the concepts and values communicated through this curriculum. A six-station Objective Structured Clinical Examination (OSCE) was designed using standardized patients to create varying Professionalism and Communication scenarios. The surgical resident learners were evaluated using these OSCEs as a baseline. The faculty then facilitated a specially designed curriculum consisting of six interactive sessions focusing on information gathering, rapport building, patient education, delivering bad news, responding to emotion, and interdisciplinary respect. At the conclusion of this curriculum, the surgical resident learners took the same six-station OSCE to determine if their professionalism and communication skills had improved. The surgical resident learners were rated by the standardized patients according to a strict task checklist of criteria at both the precurricular and postcurricular OSCEs. Improvement in the competencies of Professionalism and Communication did achieve statistical significance (P = .029 and P = .011, respectively). This study suggests that the Communication and Professionalism ACGME competencies can be taught to surgical resident learners through a carefully crafted curriculum. Furthermore, these newly learned competencies can affect surgical resident interactions with their patients positively.

4P-NPD ultra-thin films as efficient exciton blocking layers in DBP/C70 based organic solar cells

NASA Astrophysics Data System (ADS)

Patil, Bhushan R.; Liu, Yiming; Qamar, Talha; Rubahn, Horst-Günter; Madsen, Morten

2017-09-01

Exciton blocking effects from ultra-thin layers of N,N‧-di-1-naphthalenyl-N,N‧-diphenyl [1,1‧:4‧,1″:4″,1‴-quaterphenyl]-4,4‴-diamine (4P-NPD) were investigated in small molecule-based inverted organic solar cells (OSCs) using tetraphenyldibenzoperiflanthene as the electron donor material and fullerene (C70) as the electron acceptor material. The short-circuit current density (J SC) and power conversion efficiency (PCE) of the optimized OSCs with 0.7 nm thick 4P-NPD were approximately 16% and 24% higher, respectively, compared to reference devices without exciton blocking layers (EBLs). Drift diffusion-based device modeling was conducted to model the full current density-voltage (JV) characteristics and external quantum efficiency spectrum of the OSCs, and photoluminescence measurements were conducted to investigate the exciton blocking effects with increasing thicknesses of the 4P-NPD layer. Importantly, coupled optical and electrical modeling studies of the device behaviors and exciton generation rates and densities in the active layer for different 4P-NPD layer thicknesses were conducted, in order to gain a complete understanding of the observed increase in PCE for 4P-NPD layer thicknesses up to 1 nm, and the observed decrease in PCE for layer thicknesses beyond 1 nm. This work demonstrates a route for guiding the integration of EBLs in OSC devices.

Preparation of flexible organic solar cells with highly conductive and transparent metal-oxide multilayer electrodes based on silver oxide.

PubMed

Yun, Jungheum; Wang, Wei; Bae, Tae Sung; Park, Yeon Hyun; Kang, Yong-Cheol; Kim, Dong-Ho; Lee, Sunghun; Lee, Gun-Hwan; Song, Myungkwan; Kang, Jae-Wook

2013-10-23

We report that significantly more transparent yet comparably conductive AgOx films, when compared to Ag films, are synthesized by the inclusion of a remarkably small amount of oxygen (i.e., 2 or 3 atom %) in thin Ag films. An 8 nm thick AgOx (O/Ag=2.4 atom %) film embedded between 30 nm thick ITO films (ITO/AgOx/ITO) achieves a transmittance improvement of 30% when compared to a conventional ITO/Ag/ITO electrode with the same configuration by retaining the sheet resistance in the range of 10-20 Ω sq(-1). The high transmittance provides an excellent opportunity to improve the power-conversion efficiency of organic solar cells (OSCs) by successfully matching the transmittance spectral range of the electrode to the optimal absorption region of low band gap photoactive polymers, which is highly limited in OSCs utilizing conventional ITO/Ag/ITO electrodes. An improvement of the power-conversion efficiency from 4.72 to 5.88% is achieved from highly flexible organic solar cells (OSCs) fabricated on poly(ethylene terephthalate) polymer substrates by replacing the conventional ITO/Ag/ITO electrode with the ITO/AgOx/ITO electrode. This novel transparent electrode can facilitate a cost-effective, high-throughput, room-temperature fabrication solution for producing large-area flexible OSCs on heat-sensitive polymer substrates with excellent power-conversion efficiencies.

Nonfullerene Tandem Organic Solar Cells with High Open-Circuit Voltage of 1.97 V.

PubMed

Liu, Wenqing; Li, Shuixing; Huang, Jiang; Yang, Shida; Chen, Jiehuan; Zuo, Lijian; Shi, Minmin; Zhan, Xiaowei; Li, Chang-Zhi; Chen, Hongzheng

2016-11-01

Small-molecule nonfullerene-based tandem organic solar cells (OSCs) are fabricated for the first time by utilizing P3HT:SF(DPPB) 4 and PTB7-Th:IEIC bulk heterojunctions as the front and back subcells, respectively. A power conversion efficiency of 8.48% is achieved with an ultrahigh open-circuit voltage of 1.97 V, which is the highest voltage value reported to date among efficient tandem OSCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Implementation of the Forest Service Open Space Conservation Strategy in Washington State: Exploring the Role of the National Forest System

Treesearch

Richard J. Pringle; Lee K. Cerveny; Gordon A. Bradley

2015-01-01

The loss of open space was declared one of the “four threats to the health of our nation’s forests” by former USDA Forest Service Chief Dale Bosworth in 2004. Since then, the agencywide Open Space Conservation Strategy (OSCS) was released and the “four threats” were incorporated into the agency’s National Strategic Plan. These actions indicate that the OSCS is in the...

Isolation, characterization and propagation of mitotically active germ cells from adult mouse and human ovaries

PubMed Central

Woods, Dori C; Tilly, Jonathan L

2017-01-01

Accruing evidence indicates that production of new oocytes (oogenesis) and their enclosure by somatic cells (folliculogenesis) are processes not limited to the perinatal period in mammals. Endpoints ranging from oocyte counts to genetic lineage tracing and transplantation experiments support a paradigm shift in reproductive biology involving active renewal of oocyte-containing follicles during postnatal life. The recent purification of mitotically active oocyte progenitor cells, termed female germline stem cells (fGSCs) or oogonial stem cells (OSCs), from mouse and human ovaries opens up new avenues for research into the biology and clinical utility of these cells. Here we detail methods for the isolation of mouse and human OSCs from adult ovarian tissue, cultivation of the cells after purification, and characterization of the cells before and after ex vivo expansion. The latter methods include analysis of germ cell–specific markers and in vitro oogenesis, as well as the use of intraovarian transplantation to test the oocyte-forming potential of OSCs in vivo. PMID:23598447

Extragalactic photon-ALP conversion at CTA energies

DOE PAGES

Kartavtsev, A.; Raffelt, G.; Vogel, H.

2017-01-12

Magnetic fields in extragalactic space between galaxy clusters may induce conversions between photons and axion-like particles (ALPs), thereby shielding the photons from absorption on the extragalactic background light. For TeV gamma rays, the oscillation length (l osc) of the photon-ALP system becomes inevitably of the same order as the coherence length of the magnetic field l and the length over which the field changes significantly (transition length l t) due to refraction on background photons. We derive exact statistical evolution equations for the mean and variance of the photon and ALP transfer functions in the non-adiabatic regime (l osc ~more » l >> l t). We also make analytical predictions for the transfer functions in the quasi-adiabatic regime (l osc

High-performance ternary blend polymer solar cells involving both energy transfer and hole relay processes

DOE PAGES

Lu, Luyao; Chen, Wei; Xu, Tao; ...

2015-06-04

The integration of multiple materials with complementary absorptions into a single junction device is regarded as an efficient way to enhance the power conversion efficiency (PCE) of organic solar cells (OSCs). However, because of increased complexity with one more component, only limited high-performance ternary systems have been demonstrated previously. Here we report an efficient ternary blend OSC with a PCE of 9.2%. We show that the third component can reduce surface trap densities in the ternary blend. Detailed studies unravel that the improved performance results from synergistic effects of enlarged open circuit voltage, suppressed trap-assisted recombination, enhanced light absorption, increasedmore » hole extraction, efficient energy transfer and better morphology. As a result, the working mechanism and high device performance demonstrate new insights and design guidelines for high-performance ternary blend solar cells and suggest that ternary structure is a promising platform to boost the efficiency of OSCs.« less

Broadband light absorption enhancement in moth's eye nanostructured organic solar cells

NASA Astrophysics Data System (ADS)

Lan, Weixia; Cui, Yanxia; Yang, Qingyi; Lo, Ming-Fai; Lee, Chun-Sing; Zhu, Furong

2015-05-01

A comprehensive study on inverted organic solar cells (OSCs) with a moth's eye nanostructured (MEN) active layer was carried out. Performance of the MEN-based OSCs and the corresponding control planar cells, fabricated with blend of poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-bA] dithiophene-2, 6-diyl][3-fluoro-2-[(2- ethylhexyl) carbonyl]thieno[3,4-b]-thiophenediyl] (PTB7):[6,6]- phenyl-C70- butyric-acid-methyl-ester (PC70BM) was analyzed. The efficiency of the MEN-based OSCs was optimized by adjusting the height of MEN pattern in the active layer. Our experimental and theoretical results reveal that the MEN pattern enhances light absorption in the PTB7:PC70BM active layer, especially over the long wavelength region. This leads to a 7.8% increase in short circuit current density and a 6.1% increase in power conversion efficiency over those of the control planar cell.

Objective structured clinical examination for pharmacy students in Qatar: cultural and contextual barriers to assessment.

PubMed

Wilby, K J; Black, E K; Austin, Z; Mukhalalati, B; Aboulsoud, S; Khalifa, S I

2016-07-10

This study aimed to evaluate the feasibility and psychometric defensibility of implementing a comprehensive objective structured clinical examination (OSCE) on the complete pharmacy programme for pharmacy students in a Middle Eastern context, and to identify facilitators and barriers to implementation within new settings. Eight cases were developed, validated, and had standards set according to a blueprint, and were assessed with graduating pharmacy students. Assessor reliability was evaluated using inter-class coefficients (ICCs). Concurrent validity was evaluated by comparing OSCE results to professional skills course grades. Field notes were maintained to generate recommendations for implementation in other contexts. The examination pass mark was 424 points out of 700 (60.6%). All 23 participants passed. Mean performance was 74.6%. Low to moderate inter-rater reliability was obtained for analytical and global components (average ICC 0.77 and 0.48, respectively). In conclusion, OSCE was feasible in Qatar but context-related validity and reliability concerns must be addressed prior to future iterations in Qatar and elsewhere.

Assessment of Pharmacy Students' Communication Competence Using the Roter Interaction Analysis System During Objective Structured Clinical Examinations

PubMed Central

Kubota, Yoshie; Seki, Susumu; Takada, Kaori; Sakuma, Mio; Morimoto, Takeshi; Akaike, Akinori; Hiraide, Atsushi

2011-01-01

Objective To determine the value of using the Roter Interaction Analysis System during objective structured clinical examinations (OSCEs) to assess pharmacy students' communication competence. Methods As pharmacy students completed a clinical OSCE involving an interview with a simulated patient, 3 experts used a global rating scale to assess students' overall performance in the interview, and both the student's and patient's languages were coded using the Roter Interaction Analysis System (RIAS). The coders recorded the number of utterances (ie, units of spoken language) in each RIAS category. Correlations between the raters' scores and the number and types of utterances were examined. Results There was a significant correlation between students' global rating scores on the OSCE and the number of utterances in the RIAS socio-emotional category but not the RIAS business category. Conclusions The RIAS proved to be a useful tool for assessing the socio-emotional aspect of students' interview skills. PMID:21655397

Temperature-dependent Schottky barrier in high-performance organic solar cells

PubMed Central

Li, Hui; He, Dan; Zhou, Qing; Mao, Peng; Cao, Jiamin; Ding, Liming; Wang, Jizheng

2017-01-01

Organic solar cells (OSCs) have attracted great attention in the past 30 years, and the power conversion efficiency (PCE) now reaches around 10%, largely owning to the rapid material developments. Meanwhile with the progress in the device performance, more and more interests are turning to understanding the fundamental physics inside the OSCs. In the conventional bulk-heterojunction architecture, only recently it is realized that the blend/cathode Schottky junction serves as the fundamental diode for the photovoltaic function. However, few researches have focused on such junctions, and their physical properties are far from being well-understood. In this paper based on PThBDTP:PC71BM blend, we fabricated OSCs with PCE exceeding 10%, and investigated temperature-dependent behaviors of the junction diodes by various characterization including current-voltage, capacitance-voltage and impedance measurements between 70 to 290 K. We found the Schottky barrier height exhibits large inhomogeneity, which can be described by two sets of Gaussian distributions. PMID:28071700

Deformation in the hanging wall of Cretaceous HP rocks (Austroalpine Ötztal-Stubai Complex, European Eastern Alps): constraints on timing, conditions and kinematics

NASA Astrophysics Data System (ADS)

Habler, Gerlinde; Thöni, Martin; Grasemann, Bernhard; Sölva, Helmuth; Cotza, Gianluca

2010-05-01

The position and nature of the tectonic boundary between the Cretaceous eclogite facies metamorphic Texel Complex (Sölva et al. 2005, TC) and the Ötztal-Stubai Complex sensu stricto (OSC) with predominantly pre-Cretaceous tectonometamorphic imprint remained a matter of discussion (Fügenschuh et al. 2009). Sölva et al (2005) described the Cretaceous Schneeberg Normal Fault Zone (SNFZ) as the major tectonic boundary between the exhuming TC and the OSC, where the major portion of ductile deformation was partitioned into the rheologically weak Schneeberg/Monteneve Unit (SMU). In contrast, other authors proposed a model of a coherent vertical crustal section in the southern OSC (Schmid and Haas 1989), which was rotated and exhumed by erosion due to Oligocene large scale refolding (Fügenschuh et al. 2009). Here, new Rb-Sr data of muscovite and biotite from para- and orthogneisses from the Ferwalltal and Timmelsjoch areas (Austria/Italy) were correlated with mineral chemical and structural data in order to constrain the age and kinematics of the predominant deformational imprint in the OSC representing the hanging wall of the SNFZ. In the Ferwalltal the undisturbed OSC/SMU boundary is exposed. Above that boundary an amphibolite facies mylonitic foliation (Sc1) represented by the compositional layering of coarse grained Qtz, Bt and dynamically recrystallized Pl interferes with an overprinting mylonitic foliation (Sc2) with spatially heterogeneous intensity. Sc1-planes were syn-tectonically overgrown by euhedral Grt with single phase continuous prograde chemical zoning and Bt-porphyroblasts. Dc2 postdated garnet growth and caused the formation of SCC' fabrics in Bt-Pl gneisses. Still Qtz recrystallized dynamically, whereas Ms and Bt newly crystallized during Dc2. In the study area, the lithological boundaries in the OSC mainly are subparallel to the predominant foliation Sc1. These planes dip with 45-50° to the NW-NNW and show a WNW-plunging stretching lineation (LSc1

Development and implementation of an objective structured clinical examination to provide formative feedback on communication and interpersonal skills in geriatric training.

PubMed

O'Sullivan, Patricia; Chao, Serena; Russell, Matthew; Levine, Sharon; Fabiny, Anne

2008-09-01

Teaching and assessment of communication and interpersonal skills, one of the American Council for Graduate Medical Education-designated core competencies, is an important but difficult task in the training of physicians. Assessment of trainees offers an opportunity to provide explicit feedback on their skills and encourages learning. This article describes a pilot study in which clinician-educators affiliated with the geriatrics training programs at Beth Israel Deaconess Medical Center and Boston University Medical Center designed and piloted a novel Objective Structured Clinical Examination (OSCE) to assess the communication and interpersonal skills of medical, dental, and geriatric psychiatry fellows. The OSCE consisted of three stations where geriatricians and standardized patients evaluated candidates using specifically designed checklists and an abbreviated version of the Master Interview Rating Scale. Communication skills were assessed through performance of specific "real life" clinical tasks, such as obtaining a medical history, explaining a diagnosis and prognosis, giving therapeutic instructions, and counseling. Interpersonal skills were assessed through the effect of the communication between doctor and standardized patient on fostering trust, relieving anxiety, and establishing a therapeutic relationship. This pilot study demonstrated that the OSCE format of assessment provides a valid means of evaluating the communication and interpersonal skills of interdisciplinary geriatric trainees and provides a valuable forum for formative assessment and feedback. Given that geriatricians and non geriatricians involved in elder care both need communication and interpersonal skills, this novel OSCE can be used for assessment of these skills in trainees in diverse healthcare subspecialties.

Effect of low-cost interventions on the retention of knowledge and skills following Helping Babies Breathe training.

PubMed

Cordova, Erika; Al-Rousan, Tala; Castillo-Angeles, Manuel; Aftab, Saima; Nelson, Brett D

2018-04-24

To evaluate the impact of a post-Helping Babies Breathe bundle of interventions on the retention of provider-level knowledge and skills. The present prospective pre-post study following a 1-day Helping Babies Breathe training of professional midwives, physicians, and nurses was conducted in Cajamarca Province, Peru between January 1 and July 31, 2017. The interventions to improve retention included structured worksite practice before every shift, weekly in-service simulated scenarios, and monthly supervised peer-to-peer abbreviated refresher trainings. Knowledge and skills were assessed before, immediately after, and 6 months after training using two validated multiple-choice knowledge test and objective structured clinical examinations (OSCEs; OSCE A and OSCE B). Data were analyzed for changes in knowledge and skills over time and to identify predictors of performance. There were 60 learners included. No significant differences were observed between assessments immediately after training and at 6-month follow-up for knowledge scores or time-to-effective-ventilation. Pass rates for OSCE B increased from 83% immediately after training to 95% at follow-up (P=0.007). The only factor associated with a reduced time to effective ventilation at 6-month follow-up was working in a hospital (P<0.001), accounting for years of training and experience. Helping Babies Breathe knowledge and skills can be retained and even improved with simple, inexpensive interventions, including supervised on-the-job and peer-to-peer training. © 2018 International Federation of Gynecology and Obstetrics.

Development of Annealing-Free, Solution-Processable Inverted Organic Solar Cells with N-Doped Graphene Electrodes using Zinc Oxide Nanoparticles.

PubMed

Jung, Seungon; Lee, Junghyun; Seo, Jihyung; Kim, Ungsoo; Choi, Yunseong; Park, Hyesung

2018-02-14

An annealing-free process is considered as a technological advancement for the development of flexible (or wearable) organic electronic devices, which can prevent the distortion of substrates and damage to the active components of the device and simplify the overall fabrication process to increase the industrial applications. Owing to its outstanding electrical, optical, and mechanical properties, graphene is seen as a promising material that could act as a transparent conductive electrode for flexible optoelectronic devices. Owing to their high transparency and electron mobility, zinc oxide nanoparticles (ZnO-NP) are attractive and promising for their application as charge transporting materials for low-temperature processes in organic solar cells (OSCs), particularly because most charge transporting materials require annealing treatments at elevated temperatures. In this study, graphene/annealing-free ZnO-NP hybrid materials were developed for inverted OSC by successfully integrating ZnO-NP on the hydrophobic surface of graphene, thus aiming to enhance the applicability of graphene as a transparent electrode in flexible OSC systems. Chemical, optical, electrical, and morphological analyses of ZnO-NPs showed that the annealing-free process generates similar results to those provided by the conventional annealing process. The approach was effectively applied to graphene-based inverted OSCs with notable power conversion efficiencies of 8.16% and 7.41% on the solid and flexible substrates, respectively, which promises the great feasibility of graphene for emerging optoelectronic device applications.

Tough Conversations: Development of a Curriculum for Medical Students to Lead Family Meetings.

PubMed

Hagiwara, Yuya; Ross, Jeanette; Lee, Shuko; Sanchez-Reilly, Sandra

2017-12-01

Few educational interventions have been developed to teach Family Meeting (FM) communication skills at the undergraduate level. We developed an innovative curriculum to address this gap. Fourth year medical students during 2011-2013 (n = 674) completed training for conducting a FM. To assess the effectiveness of this training, students completed a FM Objective Structured Clinical Exam (OSCE) that included 15 domains rated on a 1-5 point Likert scale. Tasks included discussing prognosis, establishing goals of care and demonstrating conflict resolution skills. Students received one-to-one feedback from standardized family members and faculty observers. Group debriefings with faculty were held after the OSCE. Analysis of faculty feedback narratives revealed four themes in which students required improvement: 1) Discussing prognosis, 2) Explaining palliative care/hospice, 3) Avoiding medical jargon, and 4) Discussing cultural/religious preferences. Evaluation total mean score was 28.2 (Min 15, Max 63; SD 7.57), and identified student's need to; 1) Ask more about the degree of knowledge family members want, 2) Ask religious beliefs, and 3) Assess family members' level of education ( p < 0.001). Qualitative analysis of group debriefings suggested that student perception of the OSCE experience was positive overall. Students found the case to be realistic and immediate feedback to be helpful. Conducting a FM is an advanced skill. This study shows that it is possible to train fourth year students to lead FMs and identify their strengths, needs using a FM OSCE.

Genetics objective structured clinical exams at the Maimonides Infants & Children's Hospital of Brooklyn, New York.

PubMed

Altshuler, Lisa; Kachur, Elizabeth; Krinshpun, Shifra; Sullivan, Deborah

2008-11-01

In 2003, the Maimonides Infants & Children's Hospital received a Title VII Residency Training in Primary Care grant to integrate genetic-specific competencies into postgraduate pediatrics education. As part of that endeavor, mandatory yearly genetics objective structured clinical exams (OSCEs) were instituted for third-year residents. This article reports on the first three years of experience with this innovative educational tool.After an overview of genetic concepts, dysmorphology, and communication styles, residents complete a five-station OSCE and receive feedback from standardized patients and from the faculty who observe them. After this clinical exercise, the residents participate in a small-group debriefing session to share strategies for effective communication and clinical case management and to discuss the ethical issues that arise with these genetic cases.In three years, 60 residents have completed the genetics OSCE program. Evaluation data demonstrate that the program has been effective in both introducing genetic-specific challenges and assessing residents' clinical skills. It has helped trainees self-identify both strengths and further training needs. Pre- and postsurveys among the trainees show increased comfort levels in performing 5 of 12 genetic-related clinical tasks.We conclude that genetics OSCEs are an enriching educational tool. Merely providing trainees and practicing physicians with the latest scientific information is unlikely to prepare them for counseling patients about complex genetic issues. Developing proficiency requires focused practice and effective feedback.This article is part of a theme issue of Academic Medicine on the Title VII health professions training programs.

Light Optics for Optical Stochastic Cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andorf, Matthew; Lebedev, Valeri; Piot, Philippe

2016-06-01

In Optical Stochastic Cooling (OSC) radiation generated by a particle in a "pickup" undulator is amplified and transported to a downstream "kicker" undulator where it interacts with the same particle which radiated it. Fermilab plans to carry out both passive (no optical amplifier) and active (optical amplifier) tests of OSC at the Integrable Optics Test Accelerator (IOTA) currently in construction*. The performace of the optical system is analyzed with simulations in Synchrotron Radiation Workshop (SRW) accounting for the specific temporal and spectral properties of undulator radiation and being augmented to include dispersion of lens material.

Development of a scanning time of flight microscope and its application to the study of charge transport in phase separated structured organic semiconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul, Sanjoy; Ellman, Brett, E-mail: bellman@kent.edu; Singh, Gautam

We describe a tool for studying the two-dimensional spatial variation in electronic properties of organic semiconductors: the scanning time-of-flight microscope (STOFm). The STOFm simultaneously measures the transmittance of polarized light and time-of-flight current transients with a pixel size <30 μm, making it especially valuable for studies of the correlations of structure with charge generation and transport in liquid crystalline organic semiconductors (LC OSCs). Adapting a previously developed photopolymerization technique, we characterize the instrument using patterned samples of a LC OSC bounded by a non-semiconducting polymer matrix.

Changing Objective Structured Clinical Examinations Stations at Lunchtime During All Day Postgraduate Surgery Examinations Improves Examiner Morale and Stress.

PubMed

Brennan, Peter A; Scrimgeour, Duncan S; Patel, Sheena; Patel, Roshnee; Griffiths, Gareth; Croke, David T; Smith, Lee; Arnett, Richard

Human factors are important causes of error, but little is known about their possible effect during objective structured clinical examinations (OSCE). We have previously identified stress and pressure in OSCE examiners in the postgraduate intercollegiate Membership of the Royal College of Surgeons (MRCS) examination. After modifying examination delivery by changing OSCE stations at lunchtime with no demonstrable effect on candidate outcome, we resurveyed examiners to ascertain whether examiner experience was improved. Examiners (n = 180) from all 4 surgical colleges in the United Kingdom and Ireland were invited to complete the previously validated human factors questionnaire used in 2014. Aggregated scores for each of 4 previously identified factors were compared with the previous data. Unit-weighted z-scores and nonparametric Kruskal-Wallis methods were used to test the hypothesis that there was no difference among the median factor z-scores for each college. Individual Mann-Whitney-Wilcoxon tests (with appropriate Bonferonni corrections) were used to determine any differences between factors and the respective colleges. 141 Completed questionnaires were evaluated (78% response rate) and compared with 108 responses (90%) from the original study. Analysis was based on 26 items common to both studies. In 2014, the college with the highest candidate numbers (England) was significantly different in 1 factor (stress and pressure), compared with Edinburgh (Mann-Whitney-Wilcoxon: W = 1524, p < 0.001) and Glasgow colleges (Mann-Whitney-Wilcoxon: W = 104, p = 0.004). No differences were found among colleges in the same factor in 2016, Kruskall-Wallis: (χ 2 (3) = 1.73, p = 0.63). Analysis of responses found inconsistency among examiners regarding mistakes or omissions made when candidates were performing well. After making changes to OSCE delivery, factor scores relating to examiner stress and pressure are now improved and consistent across the surgical colleges. Stress

Use of DEAD-box polypeptide-4 (Ddx4) gene promoter-driven fluorescent reporter mice to identify mitotically active germ cells in post-natal mouse ovaries.

PubMed

Park, Eun-Sil; Tilly, Jonathan L

2015-01-01

Several laboratories have independently isolated mitotically active germ cells, termed female germline stem cells or oogonial stem cells (OSCs), from adult mouse ovaries. However, a recent study using Ddx4-Cre;Rosa26 reporter mice concluded that such germ cells do not exist. Given the disparity in conclusions drawn in this study compared with others, we felt it was important to re-assess the utility of Ddx4-Cre;Rosa26 reporter mice for identification of OSCs in adult mouse ovaries. Transgenic Ddx4-Cre mice were crossed with Rosa26(tdTm/tdTm) mice to drive restricted tomato red (tdTm) gene expression in cells in which the Ddx4 gene promoter has been activated. Crude dispersion of ovaries from recombined offspring generated cell fractions containing tdTm-positive immature oocytes, which are incapable of proliferation and thus probably represent the uncharacterized reporter-positive ovarian cells identified in the paper Zhang et al. (2012) as being mitotically inactive. Dispersed ovaries further subjected to fluorescence-activated cell sorting yielded a large population of non-germline tdTm-positive cells, indicative of promoter 'leakiness' in the Ddx4-Cre mouse line. Nonetheless, a small percentage of these tdTm-positive cells exhibited externalized (extracellular, ec) expression of Ddx4 protein (ecDdx4-positive), expressed markers of primitive germ cells but not of oocytes, and actively proliferated in culture, all of which are characteristic features of OSCs. Thus, crude dispersion of ovaries collected from Ddx4 gene promoter-driven reporter mice is not, by itself, a reliable approach to identify OSCs, whereas the same ovarian dispersates further subjected to cell sorting strategies yield purified OSCs that can be expanded in culture. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Dexamethasone and supportive care with or without whole brain radiotherapy in treating patients with non-small cell lung cancer with brain metastases unsuitable for resection or stereotactic radiotherapy (QUARTZ): results from a phase 3, non-inferiority, randomised trial.

PubMed

Mulvenna, Paula; Nankivell, Matthew; Barton, Rachael; Faivre-Finn, Corinne; Wilson, Paula; McColl, Elaine; Moore, Barbara; Brisbane, Iona; Ardron, David; Holt, Tanya; Morgan, Sally; Lee, Caroline; Waite, Kathryn; Bayman, Neil; Pugh, Cheryl; Sydes, Benjamin; Stephens, Richard; Parmar, Mahesh K; Langley, Ruth E

2016-10-22

Whole brain radiotherapy (WBRT) and dexamethasone are widely used to treat brain metastases from non-small cell lung cancer (NSCLC), although there have been no randomised clinical trials showing that WBRT improves either quality of life or overall survival. Even after treatment with WBRT, the prognosis of this patient group is poor. We aimed to establish whether WBRT could be omitted without a significant effect on survival or quality of life. The Quality of Life after Treatment for Brain Metastases (QUARTZ) study is a non-inferiority, phase 3 randomised trial done at 69 UK and three Australian centres. NSCLC patients with brain metastases unsuitable for surgical resection or stereotactic radiotherapy were randomly assigned (1:1) to optimal supportive care (OSC) including dexamethasone plus WBRT (20 Gy in five daily fractions) or OSC alone (including dexamethasone). The dose of dexamethasone was determined by the patients' symptoms and titrated downwards if symptoms improved. Allocation to treatment group was done by a phone call from the hospital to the Medical Research Council Clinical Trials Unit at University College London using a minimisation programme with a random element and stratification by centre, Karnofsky Performance Status (KPS), gender, status of brain metastases, and the status of primary lung cancer. The primary outcome measure was quality-adjusted life-years (QALYs). QALYs were generated from overall survival and patients' weekly completion of the EQ-5D questionnaire. Treatment with OSC alone was considered non-inferior if it was no more than 7 QALY days worse than treatment with WBRT plus OSC, which required 534 patients (80% power, 5% [one-sided] significance level). Analysis was done by intention to treat for all randomly assigned patients. The trial is registered with ISRCTN, number ISRCTN3826061. Between March 2, 2007, and Aug 29, 2014, 538 patients were recruited from 69 UK and three Australian centres, and were randomly assigned to

Comparison of Nanohole-Type and Nanopillar-Type Patterned Metallic Electrodes Incorporated in Organic Solar Cells

NASA Astrophysics Data System (ADS)

Wang, Wenyan; Cui, Yanxia; Fung, Kin Hung; Zhang, Ye; Ji, Ting; Hao, Yuying

2017-09-01

Both the nanohole- and nanopillar-type patterned metallic electrodes (PMEs) have been introduced in organic solar cells (OSCs) for improving device performances experimentally, but there is few work addressing the similarities and differences between them. In this theoretical work, we systematically compare the impact of the nanohole- and nanopillar-type PMEs on the performance of an OSC based on hybridized cavity resonances. By optimizing the geometrical parameters of each PME, we obtained an interesting result that the integrated absorption efficiencies in the active layer with different optimized PMEs are almost the same (both are equal to 82.4%), outperforming that of the planar control by 9.9%. Though the absorption enhancement spectra of the two different optimal devices are similar as well, the mechanisms of light trapping at the corresponding enhancement peaks are distinct from each other. In a comprehensive view, the nanopillar-type PME is suggested to be applied in the present system, since its optimal design has a moderate filling ratio, which is much easier to fabricate than its counterpart. This work could contribute to the development of high-efficiency OSCs.

Exciton delocalization incorporated drift-diffusion model for bulk-heterojunction organic solar cells

NASA Astrophysics Data System (ADS)

Wang, Zi Shuai; Sha, Wei E. I.; Choy, Wallace C. H.

2016-12-01

Modeling the charge-generation process is highly important to understand device physics and optimize power conversion efficiency of bulk-heterojunction organic solar cells (OSCs). Free carriers are generated by both ultrafast exciton delocalization and slow exciton diffusion and dissociation at the heterojunction interface. In this work, we developed a systematic numerical simulation to describe the charge-generation process by a modified drift-diffusion model. The transport, recombination, and collection of free carriers are incorporated to fully capture the device response. The theoretical results match well with the state-of-the-art high-performance organic solar cells. It is demonstrated that the increase of exciton delocalization ratio reduces the energy loss in the exciton diffusion-dissociation process, and thus, significantly improves the device efficiency, especially for the short-circuit current. By changing the exciton delocalization ratio, OSC performances are comprehensively investigated under the conditions of short-circuit and open-circuit. Particularly, bulk recombination dependent fill factor saturation is unveiled and understood. As a fundamental electrical analysis of the delocalization mechanism, our work is important to understand and optimize the high-performance OSCs.

Series circuit of organic thin-film solar cells for conversion of water into hydrogen.

PubMed

Aoki, Atsushi; Naruse, Mitsuru; Abe, Takayuki

2013-07-22

A series circuit of bulk hetero-junction (BHJ) organic thin-film solar cells (OSCs) is investigated for electrolyzing water to gaseous hydrogen and oxygen. The BHJ OSCs applied consist of poly(3-hexylthiophene) as a donor and [6,6]-phenyl C61 butyric acid methyl ester as an acceptor. A series circuit of six such OSC units has an open circuit voltage (V(oc)) of 3.4 V, which is enough to electrolyze water. The short circuit current (J(sc)), fill factor (FF), and energy conversion efficiency (η) are independent of the number of unit cells. A maximum electric power of 8.86 mW cm(-2) is obtained at the voltage of 2.35 V. By combining a water electrolysis cell with the series circuit solar cells, the electrolyzing current and voltage obtained are 1.09 mA and 2.3 V under a simulated solar light irradiation (100 mW cm(-2), AM1.5G), and in one hour 0.65 mL hydrogen is generated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rational Design of Diketopyrrolopyrrole-Based Small Molecules as Donating Materials for Organic Solar Cells

PubMed Central

Jin, Ruifa; Wang, Kai

2015-01-01

A series of diketopyrrolopyrrole-based small molecules have been designed to explore their optical, electronic, and charge transport properties as organic solar cell (OSCs) materials. The calculation results showed that the designed molecules can lower the band gap and extend the absorption spectrum towards longer wavelengths. The designed molecules own the large longest wavelength of absorption spectra, the oscillator strength, and absorption region values. The optical, electronic, and charge transport properties of the designed molecules are affected by the introduction of different π-bridges and end groups. We have also predicted the mobility of the designed molecule with the lowest total energies. Our results reveal that the designed molecules are expected to be promising candidates for OSC materials. Additionally, the designed molecules are expected to be promising candidates for electron and/or hole transport materials. On the basis of our results, we suggest that molecules under investigation are suitable donors for [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and its derivatives as acceptors of OSCs. PMID:26343640

An Al-doped ZnO electrode grown by highly efficient cylindrical rotating magnetron sputtering for low cost organic photovoltaics

NASA Astrophysics Data System (ADS)

Park, Jun-Hyuk; Ahn, Kyung-Jun; Park, Kang-Il; Na, Seok-In; Kim, Han-Ki

2010-03-01

We report the characteristics of Al-doped zinc oxide (AZO) films prepared by a highly efficient cylindrical rotating magnetron sputtering (CRMS) system for use as a transparent conducting electrode in cost-efficient bulk hetero-junction organic solar cells (OSCs). Using a rotating cylindrical type cathode with an AZO target, whose usage was above 80%, we were able to obtain a low cost and indium free AZO electrode with a low sheet resistance of ~4.59 Ω/sq, a high transparency of 85% in the visible wavelength region and a work function of 4.9 eV at a substrate temperature of 230 °C. Moreover, the neutral poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonate) based OSC fabricated on the CRMS-grown AZO electrode at 230 °C showed an open circuit voltage of 0.5 V, a short circuit current of 8.94 mA cm-2, a fill factor of 45% and power conversion efficiency of 2.01%, indicating that CRMS is a promising cost-efficient AZO deposition technique for low cost OSCs.

Triphenylamine-Based Push–Pull Molecule for Photovoltaic Applications: From Synthesis to Ultrafast Device Photophysics

PubMed Central

2017-01-01

Small push–pull molecules attract much attention as prospective donor materials for organic solar cells (OSCs). By chemical engineering, it is possible to combine a number of attractive properties such as broad absorption, efficient charge separation, and vacuum and solution processabilities in a single molecule. Here we report the synthesis and early time photophysics of such a molecule, TPA-2T-DCV-Me, based on the triphenylamine (TPA) donor core and dicyanovinyl (DCV) acceptor end group connected by a thiophene bridge. Using time-resolved photoinduced absorption and photoluminescence, we demonstrate that in blends with [70]PCBM the molecule works both as an electron donor and hole acceptor, thereby allowing for two independent channels of charge generation. The charge-generation process is followed by the recombination of interfacial charge transfer states that takes place on the subnanosecond time scale as revealed by time-resolved photoluminescence and nongeminate recombination as follows from the OSC performance. Our findings demonstrate the potential of TPA-DCV-based molecules as donor materials for both solution-processed and vacuum-deposited OSCs. PMID:28413568

The next (re)generation of ovarian biology and fertility in women: is current science tomorrow's practice?

PubMed

Woods, Dori C; Tilly, Jonathan L

2012-07-01

Stem cell-based strategies for ovarian regeneration and oocyte production have been proposed as future clinical therapies for treating infertility in women. However, utilization of embryonic stem cells or induced pluripotent stem cells to produce oocytes has had limited success in vitro. A recent report of the isolation and characterization of endogenous oocyte-producing or oogonial stem cells (OSCs) from ovaries of reproductive age women describes the first stable and pure human female germ cell culture model in which a subset of cells appear to initiate and complete meiosis. In addition, purified human OSCs introduced into adult human ovarian cortical tissue generate oocytes that arrest at the diplotene stage of meiosis and successfully recruit granulosa cells to form new primordial follicles. This overview examines the current landscape of in vitro and in vivo gametogenesis from stem cells, with emphasis on generation of human oocytes. Future research objectives for this area of work, as well as potential clinical applications involving the use of human OSCs, are discussed. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Realization of Intrinsically Stretchable Organic Solar Cells Enabled by Charge-Extraction Layer and Photoactive Material Engineering.

PubMed

Hsieh, Yun-Ting; Chen, Jung-Yao; Fukuta, Seijiro; Lin, Po-Chen; Higashihara, Tomoya; Chueh, Chu-Chen; Chen, Wen-Chang

2018-06-12

The rapid development of wearable electronic devices has prompted a strong demand to develop stretchable organic solar cells (OSCs) to serve as the advanced powering systems. However, to realize an intrinsically stretchable OSC is challenging because it requires all the constituent layers to possess certain elastic properties. It thus necessitates a combined engineering of charge-transporting layers and photoactive materials. Herein, we first describe a stretchable electron-extraction layer using a blend of poly[(9,9-bis(3'-( N, N-dimethylamino)propyl)-2,7-fluorene)- alt-2,7-(9,9-dioctylfluorene)] (PFN) and nitrile butadiene rubber (NBR, Nipol 1072). This hybrid PFN/NBR layer exhibits a much lower Derjaguin-Muller-Toporov modulus (0.45 GPa) than the value (1.25 GPa) of the pristine PFN and could withstand a high strain (60% strain) without showing any cracks. Moreover, besides enriching the stretchability of PFN, the terminal carboxyl groups of NBR can ionize PFN to promote its solution-processability in polar solvents and to ensure the interfacial dipole formation at the corresponding interface in the device, as evidenced by the Fourier transform infrared and ultraviolet photoelectron spectroscopy analyses. By further coupling the replacement of [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) with nonfullerene acceptors owing to better mechanical stretchability in the photoactive layer, OSCs with improved intrinsically stretchability and performance were demonstrated. An all-polymer OSC can exhibit a power conversion efficiency of 2.82% after 10% stretching, surpassing the PCBM-based device that can only withstand 5% strain.

Molecular dynamics and charge transport in organic semiconductors: a classical approach to modeling electron transfer

DOE PAGES

Pelzer, Kenley M.; Vázquez-Mayagoitia, Álvaro; Ratcliff, Laura E.; ...

2017-01-01

Organic photovoltaics (OPVs) are a promising carbon-neutral energy conversion technology, with recent improvements pushing power conversion efficiencies over 10%. A major factor limiting OPV performance is inefficiency of charge transport in organic semiconducting materials (OSCs). Due to strong coupling with lattice degrees of freedom, the charges form polarons, localized quasi-particles comprised of charges dressed with phonons. These polarons can be conceptualized as pseudo-atoms with a greater effective mass than a bare charge. Here we propose that due to this increased mass, polarons can be modeled with Langevin molecular dynamics (LMD), a classical approach with a computational cost much lower thanmore » most quantum mechanical methods. Here we present LMD simulations of charge transfer between a pair of fullerene molecules, which commonly serve as electron acceptors in OSCs. We find transfer rates consistent with experimental measurements of charge mobility, suggesting that this method may provide quantitative predictions of efficiency when used to simulate materials on the device scale. Our approach also offers information that is not captured in the overall transfer rate or mobility: in the simulation data, we observe exactly when and why intermolecular transfer events occur. In addition, we demonstrate that these simulations can shed light on the properties of polarons in OSCs. In conclusion, much remains to be learned about these quasi-particles, and there are no widely accepted methods for calculating properties such as effective mass and friction. Lastly, our model offers a promising approach to exploring mass and friction as well as providing insight into the details of polaron transport in OSCs.« less

A cost-benefit analysis of the outpatient smoking cessation services in Taiwan from a societal viewpoint.

PubMed

Chen, Pei-Ching; Lee, Yue-Chune; Tsai, Shih-Tzu; Lai, Chih-Kuan

2012-05-01

This study applied a cost-benefit analysis from a societal viewpoint to evaluate the Outpatient Smoking Cessation Services (OSCS) program. The costs measured in this study include the cost to the health sector, non-health sectors, the patients and their family, as well as the loss of productivity as a result of smoking. The benefits measured the medical costs savings and the earnings due to the increased life expectancy of a person that has stopped smoking for 15 years. Data were obtained from the primary data of a telephone survey, the literatures and reports from the Outpatient Smoking Cessation Management Center and government. Sensitivity analyses were conducted to verify the robustness of the results. There were 169,761 cases that participated in the outpatient smoking cessation program in the years 2007 and 2008, of those cases, 8,282 successfully stopped smoking. The total cost of the OSCS program was 18 million USD. The total benefits of the program were 215 million USD with a 3% discount rate; the net benefit to society was 196 million USD. After conducting sensitivity analyses on the different abstinence, relapse, and discount rates, from a societal perspective, the benefits still far exceeded the costs, while from a health care perspective, there was only a net benefit when the respondent's abstinence rate was used. From a societal perspective, the OSCS program in Taiwan is cost-beneficial. This study provides partial support for the policy makers to increase the budget and expand the OSCS program.

Improving Communication With Surrogate Decision-Makers: A Pilot Initiative.

PubMed

Meltzer, Ellen C; Shi, Zhenzhen; Suppes, Alexandra; Hersh, Jennifer E; Orlander, Jay D; Calhoun, Aaron W; Tung, Judy; Logio, Lia; Manna, Ruth; Bialer, Philip A; Acres, Cathleen A; Fins, Joseph J

2017-08-01

Difficult conversations in medical care often occur between physicians and patients' surrogates, individuals entrusted with medical decisions for patients who lack the capacity to make them. Poor communication between patients' surrogates and physicians may exacerbate anxiety and guilt for surrogates, and may contribute to physician stress and burnout. This pilot study assesses the effectiveness of an experiential learning workshop that was conducted in a clinical setting, and aimed at improving resident physician communication skills with a focus on surrogate decision-making. From April through June 2016, we assessed internal medicine residents' baseline communication skills through an objective structured clinical examination (OSCE) with actors representing standardized surrogates. After an intensive, 6-hour communication skills workshop, residents were reassessed via an OSCE on the same day. A faculty facilitator and the surrogate evaluated participants' communication skills via the expanded Gap Kalamazoo Consensus Statement Assessment Form. Wilcoxon signed rank tests (α of .05) compared mean pre- and postworkshop scores. Of 44 residents, 33 (75%) participated. Participants' average preworkshop OSCE scores ( M  = 3.3, SD = 0.9) were significantly lower than postworkshop scores ( M  = 4.3; SD = 0.8; Z  = 4.193; P  < .001; effect size r  = 0.52). After the workshop, the majority of participants self-reported feeling "more confident." Residents' communication skills specific to surrogate decision-making benefit from focused interventions. Our pilot assessment of a workshop showed promise, and additionally demonstrated the feasibility of bringing OSCEs and simulated encounters into a busy clinical practice.

The 360-degree evaluation model: A method for assessing competency in graduate nursing students. A pilot research study.

PubMed

Cormack, Carrie L; Jensen, Elizabeth; Durham, Catherine O; Smith, Gigi; Dumas, Bonnie

2018-05-01

The 360 Degree Evaluation Model is one means to provide a comprehensive view of clinical competency and readiness for progression in an online nursing program. This pilot project aimed to evaluate the effectiveness of implementing a 360 Degree Evaluation of clinical competency of graduate advanced practice nursing students. The 360 Degree Evaluation, adapted from corporate industry, encompasses assessment of student knowledge, skills, behaviors and attitudes and validates student's progression from novice to competent. Cohort of advanced practice nursing students in four progressive clinical semesters. Graduate advanced practice nursing students (N = 54). Descriptive statistics and Jonckheere's Trend Test were used to evaluate OSCE's scores from graded rubric, standardized patient survey scores, student reflection and preceptor evaluation. We identified all students passed the four OSCEs during a first attempt or second attempt. Scaffolding OSCE's over time allowed faculty to identify cohort weakness and create subsequent learning opportunities. Standardized patients' evaluation of the students' performance in the domains of knowledge, skills and attitudes, showed high scores of 96% in all OSCEs. Students' self-reflection comments were a mix of strengths and weaknesses in their self-evaluation, demonstrating themes as students progressed. Preceptor evaluation scores revealed the largest increase in knowledge and learning skills (NONPF domain 1), from an aggregate average of 90% in the first clinical course, to an average of 95%. The 360 Degree Evaluation Model provided a comprehensive evaluation of the student and critical information for the faculty ensuring individual student and cohort data and ability to analyze cohort themes. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Relationship between Senior Year Examinations at a Medical School and the Korean Medical Licensing Examination.

PubMed

Jung, Ki Hoon; Jung, Ho Keun; Lee, Kwan

2009-03-01

Most medical schools prepare for the Korean medical licensing examination (KMLE) with various tests. By assessing the degree to which these exams and the KMLE are related, students, professors, and institutions can be well prepared and some schools use these exams as predictive tools for KMLE scores. Therefore, we determined the relevance of KMLE results to midterm exams and the objective structured clinical examination (OSCE), administered to senior students at a medical school. From 2002 to 2004, KMLE results were compared with midterm examinations, the KMLE, and the OSCE. The total score, or T-score, of the KMLE was used, as was a pass or nonpass score. Windows SPSS 14.0 and MedCalc 9.0 were used for statistical analysis. The yearly correlation coefficient of the KMLE and school exams was highest for the midterm exams in 2002 and the KMLE in 2003 and 2004. The correlation coefficient of midterm exams and the KMLE were related to a high degree, yet the values were as low as that of the OSCE. Compared with the KMLE results, the sensitivity and specificity of the average midterm exam were 100.0% and 93.8%, and the sensitivity and specificity of the average trial exams were 100.0% and 95.8%, respectively. In conclusion, the KMLE results have a strong relationship with midterm exams, trial exams, and the combination of midterm and trial exams, but not with the OSCE. Thus, we believe that using both midterm exams and trial exams to predict KMLE results is superior to the use of only one type of school exam.

Molecular dynamics and charge transport in organic semiconductors: a classical approach to modeling electron transfer† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc04547b Click here for additional data file.

PubMed Central

Vázquez-Mayagoitia, Álvaro; Ratcliff, Laura E.; Tretiak, Sergei; Bair, Raymond A.; Gray, Stephen K.; Van Voorhis, Troy; Larsen, Ross E.; Darling, Seth B.

2017-01-01

Organic photovoltaics (OPVs) are a promising carbon-neutral energy conversion technology, with recent improvements pushing power conversion efficiencies over 10%. A major factor limiting OPV performance is inefficiency of charge transport in organic semiconducting materials (OSCs). Due to strong coupling with lattice degrees of freedom, the charges form polarons, localized quasi-particles comprised of charges dressed with phonons. These polarons can be conceptualized as pseudo-atoms with a greater effective mass than a bare charge. We propose that due to this increased mass, polarons can be modeled with Langevin molecular dynamics (LMD), a classical approach with a computational cost much lower than most quantum mechanical methods. Here we present LMD simulations of charge transfer between a pair of fullerene molecules, which commonly serve as electron acceptors in OSCs. We find transfer rates consistent with experimental measurements of charge mobility, suggesting that this method may provide quantitative predictions of efficiency when used to simulate materials on the device scale. Our approach also offers information that is not captured in the overall transfer rate or mobility: in the simulation data, we observe exactly when and why intermolecular transfer events occur. In addition, we demonstrate that these simulations can shed light on the properties of polarons in OSCs. Much remains to be learned about these quasi-particles, and there are no widely accepted methods for calculating properties such as effective mass and friction. Our model offers a promising approach to exploring mass and friction as well as providing insight into the details of polaron transport in OSCs. PMID:28553494

Point-of-view writing: A method for increasing medical students' empathy, identification and expression of emotion, and insight.

PubMed

Shapiro, Johanna; Rucker, Lloyd; Boker, John; Lie, Desiree

2006-03-01

Although interest exists among medical educators in using writing that reflects on clinical experience to enhance medical students' communication skills, empathy, and overall professionalism, little empirical research documents the value of this approach. This study explored whether students trained in one type of writing would first demonstrate increased awareness of emotional aspects of a clinical encounter in their writing; and second, be evaluated more positively in an OSCE situation by standardized patients. Ninety-two students were assigned to either a point-of-view writing or a clinical reasoning condition as part of a second year doctoring course. At the end of the year, students were evaluated in an OSCE format on 3 cases, and completed a writing assignment about an ER death from cardiac arrest. Student essays were scored according to presence or absence of various themes. A linguistic analysis of the essays was also performed. Point-of-view and clinical reasoning group scores were compared on both measures, as well as on the standardized patient OSCE ratings. Students trained in point-of-view writing demonstrated significantly more awareness of emotional and spiritual aspects of a paper case in a writing assignment than did students trained in clinical reasoning. By contrast, students in the clinical reasoning group were more likely to distance from the scenario. The two groups did not differ on SP OSCE ratings. Training in point-of-view writing can improve medical students' written skills on certain affective dimensions. It is not clear that these skills can translate into clinical behavior.

Wet Deposition Flux of Reactive Organic Carbon

NASA Astrophysics Data System (ADS)

Safieddine, S.; Heald, C. L.

2016-12-01

Reactive organic carbon (ROC) is the sum of non-methane volatile organic compounds (NMVOCs) and primary and secondary organic aerosols (OA). ROC plays a key role in driving the chemistry of the atmosphere, affecting the hydroxyl radical concentrations, methane lifetime, ozone formation, heterogeneous chemical reactions, and cloud formation, thereby impacting human health and climate. Uncertainties on the lifecycle of ROC in the atmosphere remain large. In part this can be attributed to the large uncertainties associated with the wet deposition fluxes. Little is known about the global magnitude of wet deposition as a sink of both gas and particle phase organic carbon, making this an important area for research and sensitivity testing in order to better understand the global ROC budget. In this study, we simulate the wet deposition fluxes of the reactive organic carbon of the troposphere using a global chemistry transport model, GEOS-Chem. We start by showing the current modeled global distribution of ROC wet deposition fluxes and investigate the sensitivity of these fluxes to variability in Henry's law solubility constants and spatial resolution. The average carbon oxidation state (OSc) is a useful metric that depicts the degree of oxidation of atmospheric reactive carbon. Here, we present for the first time the simulated gas and particle phase OSc of the global troposphere. We compare the OSc in the wet deposited reactive carbon flux and the dry deposited reactive carbon flux to the OSc of atmospheric ROC to gain insight into the degree of oxidation in deposited material and, more generally, the aging of organic material in the troposphere.

Evidence for spin injection and transport in solution-processed TIPS-pentacene at room temperature

NASA Astrophysics Data System (ADS)

Mooser, S.; Cooper, J. F. K.; Banger, K. K.; Wunderlich, J.; Sirringhaus, H.

2012-10-01

Recently, there has been growing interest in the field of organic spintronics, where the research on organic semiconductors (OSCs) has extended from the complex aspects of charge carrier transport to the study of the spin transport properties of those anisotropic and partly localized systems.1 Furthermore, solution-processed OSCs are not only interesting due to their technological applications, but it has recently been shown in 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) thin film transistors that they can exhibit a negative temperature coefficient of the mobility due to localized transport limited by thermal lattice fluctuations.2 Here, spin injection and transport in solution-processed TIPS-pentacene are investigated exploiting vertical CoPt/TIPSpentacene/AlOx/Co spin valve architectures.3 The antiparallel magnetization state of the relative orientation of CoPt and Co is achieved due to their different coercive fields. A spin valve effect is detected from T = 175 K up to room temperature, where the resistance of the device is lower for the antiparallel magnetization state. The first observation of the scaling of the magnetoresistance (MR) with the bulk mobility of the OSC as a function of temperature, together with the dependence of the MR on the interlayer thickness, clearly indicates spin injection and transport in TIPS-pentacene. From OSC-spacer thickness-dependent MR measurements, a spin relaxation length of TIPS-pentacene of (24+/-6) nm and a spin relaxation time of approximately 3.5 μs at room temperature are estimated, taking the measured bulk mobility of holes into account.

Intensive point-of-care ultrasound training with long-term follow-up in a cohort of Rwandan physicians.

PubMed

Henwood, Patricia C; Mackenzie, David C; Rempell, Joshua S; Douglass, Emily; Dukundane, Damas; Liteplo, Andrew S; Leo, Megan M; Murray, Alice F; Vaillancourt, Samuel; Dean, Anthony J; Lewiss, Resa E; Rulisa, Stephen; Krebs, Elizabeth; Raja Rao, A K; Rudakemwa, Emmanuel; Rusanganwa, Vincent; Kyanmanywa, Patrick; Noble, Vicki E

2016-12-01

We delivered a point-of-care ultrasound training programme in a resource-limited setting in Rwanda, and sought to determine participants' knowledge and skill retention. We also measured trainees' assessment of the usefulness of ultrasound in clinical practice. This was a prospective cohort study of 17 Rwandan physicians participating in a point-of-care ultrasound training programme. The follow-up period was 1 year. Participants completed a 10-day ultrasound course, with follow-up training delivered over the subsequent 12 months. Trainee knowledge acquisition and skill retention were assessed via observed structured clinical examinations (OSCEs) administered at six points during the study, and an image-based assessment completed at three points. Trainees reported minimal structured ultrasound education and little confidence using point-of-care ultrasound before the training. Mean scores on the image-based assessment increased from 36.9% (95% CI 32-41.8%) before the initial 10-day training to 74.3% afterwards (95% CI 69.4-79.2; P < 0.001). The mean score on the initial OSCE after the introductory course was 81.7% (95% CI 78-85.4%). The mean OSCE performance at each subsequent evaluation was at least 75%, and the mean OSCE score at the 58-week follow up was 84.9% (95% CI 80.9-88.9%). Physicians providing acute care in a resource-limited setting demonstrated sustained improvement in their ultrasound knowledge and skill 1 year after completing a clinical ultrasound training programme. They also reported improvements in their ability to provide patient care and in job satisfaction. © 2016 John Wiley & Sons Ltd.

9.73% Efficiency Nonfullerene All Organic Small Molecule Solar Cells with Absorption-Complementary Donor and Acceptor.

PubMed

Bin, Haijun; Yang, Yankang; Zhang, Zhi-Guo; Ye, Long; Ghasemi, Masoud; Chen, Shanshan; Zhang, Yindong; Zhang, Chunfeng; Sun, Chenkai; Xue, Lingwei; Yang, Changduk; Ade, Harald; Li, Yongfang

2017-03-29

In the last two years, polymer solar cells (PSCs) developed quickly with n-type organic semiconductor (n-OSs) as acceptor. In contrast, the research progress of nonfullerene organic solar cells (OSCs) with organic small molecule as donor and the n-OS as acceptor lags behind. Here, we synthesized a D-A structured medium bandgap organic small molecule H11 with bithienyl-benzodithiophene (BDTT) as central donor unit and fluorobenzotriazole as acceptor unit, and achieved a power conversion efficiency (PCE) of 9.73% for the all organic small molecules OSCs with H11 as donor and a low bandgap n-OS IDIC as acceptor. A control molecule H12 without thiophene conjugated side chains on the BDT unit was also synthesized for investigating the effect of the thiophene conjugated side chains on the photovoltaic performance of the p-type organic semiconductors (p-OSs). Compared with H12, the 2D-conjugated H11 with thiophene conjugated side chains shows intense absorption, low-lying HOMO energy level, higher hole mobility and ordered bimodal crystallite packing in the blend films. Moreover, a larger interaction parameter (χ) was observed in the H11 blends calculated from Hansen solubility parameters and differential scanning calorimetry measurements. These special features combined with the complementary absorption of H11 donor and IDIC acceptor resulted in the best PCE of 9.73% for nonfullerene all small molecule OSCs up to date. Our results indicate that fluorobenzotriazole based 2D conjugated p-OSs are promising medium bandgap donors in the nonfullerene OSCs.

Resident Ratings of Communication Skills Using the Kalamazoo Adapted Checklist.

PubMed

Porcerelli, John H; Brennan, Simone; Carty, Jennifer; Ziadni, Maisa; Markova, Tsveti

2015-09-01

The Kalamazoo Essential Elements Communication Checklist-Adapted (KEECC-A) is a well-regarded instrument for evaluating communication and interpersonal skills. To date, little research has been conducted that assesses the accuracy of resident self-ratings of their communication skills. To assess whether residents can accurately self-rate communication skills, using the KEECC-A, during an objective structured clinical examination (OSCE). A group of 104 residents from 8 specialties completed a multistation OSCE as part of an institutional communication skills curriculum conducted at a single institution. Standardized patients (SPs) and observers were trained in rating communication skills using the KEECC-A. Standardized patient ratings and resident self-ratings were completed immediately following each OSCE encounter, and trained observers rated archived videotapes of the encounters. Resident self-ratings and SP ratings using the KEECC-A were significantly correlated (r104  = 0.238, P = .02), as were resident self-ratings and observer ratings (r104  = 0.284, P = .004). The correlation between the SP ratings and observer (r104  = 0.378, P = .001) ratings were larger in magnitude, but not significantly different (P > .05) from resident/SP or resident/observer correlations. The results suggest that residents, with a modicum of training using the KEECC-A, can accurately rate their own communication and interpersonal skills during an OSCE. Using trained observers to rate resident communication skills provides a unique opportunity for evaluating SP and resident self-ratings. Our findings also lend further support for the reliability and validity of the KEECC-A.

GPU-accelerated regularized iterative reconstruction for few-view cone beam CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matenine, Dmitri, E-mail: dmitri.matenine.1@ulaval.ca; Goussard, Yves, E-mail: yves.goussard@polymtl.ca; Després, Philippe, E-mail: philippe.despres@phy.ulaval.ca

2015-04-15

Purpose: The present work proposes an iterative reconstruction technique designed for x-ray transmission computed tomography (CT). The main objective is to provide a model-based solution to the cone-beam CT reconstruction problem, yielding accurate low-dose images via few-views acquisitions in clinically acceptable time frames. Methods: The proposed technique combines a modified ordered subsets convex (OSC) algorithm and the total variation minimization (TV) regularization technique and is called OSC-TV. The number of subsets of each OSC iteration follows a reduction pattern in order to ensure the best performance of the regularization method. Considering the high computational cost of the algorithm, it ismore » implemented on a graphics processing unit, using parallelization to accelerate computations. Results: The reconstructions were performed on computer-simulated as well as human pelvic cone-beam CT projection data and image quality was assessed. In terms of convergence and image quality, OSC-TV performs well in reconstruction of low-dose cone-beam CT data obtained via a few-view acquisition protocol. It compares favorably to the few-view TV-regularized projections onto convex sets (POCS-TV) algorithm. It also appears to be a viable alternative to full-dataset filtered backprojection. Execution times are of 1–2 min and are compatible with the typical clinical workflow for nonreal-time applications. Conclusions: Considering the image quality and execution times, this method may be useful for reconstruction of low-dose clinical acquisitions. It may be of particular benefit to patients who undergo multiple acquisitions by reducing the overall imaging radiation dose and associated risks.« less

Developments in the photonics program at OSC

NASA Astrophysics Data System (ADS)

Peyghambarian, N.

2014-10-01

The photonics program at the College of Optical Sciences started nearly 30 years ago. In 1984, the program was focused on development of femtosecond laser sources and their use in investigating semiconductor carrier dynamics. The program grew into polymer and organic optics in late 1989 and was strengthened by the winning of the CAMP MURI from ONR in 1995 that was focused on multifunctional polymers including photorefractive polymers, organic light emitting diodes and 3D direct laser writing. Also in 1995, the areas of glass waveguide and fiber optic materials and devices were added to the program. In 2008, the optical communication and future internet research was started through winning the CIAN NSF ERC. Expertise in thin films, optical storage and the fundamental aspects of light are elements of the overall research program. Holographic 3D display, autofocus lenses, bio-medical imaging and devices for vision have also been ongoing research areas.

Unsteady Low-Speed Windtunnel Test of a Straked Delta Wing, Oscillating in Pitch. Part 4. Plots of Time Histories of Pressures and Overall Loads

DTIC Science & Technology

1988-04-01

0132 I...8217 ".,. /T 1I~ i / V - . - 41 - 176- ,,i ALFHA . HR PMONIC [d g I " OSC I LLRT I ONS jt4’I.’’ 2.’, a" ..0Lr’rH :4.23 de, Z8.@8 ~ ~ _ A P A = 669 deg I Ee...ILLPT IONC𔄁 ki 4C %I rdc .110 V.. 14.00 ALPH04O [,F~ H V; I3 ~c A . .b 4.0 ’D 2 oe PL H 4 rI-- - 204 - 11 p <~ HARMONIC OSC ILLAT IONS PUN * 4S6[

Effect of pentacene/Ag anode buffer and UV-ozone treatment on durability of small-molecule organic solar cells

NASA Astrophysics Data System (ADS)

Inagaki, S.; Sueoka, S.; Harafuji, K.

2017-06-01

Three surface modifications of indium tin oxide (ITO) are experimentally investigated to improve the performance of small-molecule organic solar cells (OSCs) with an ITO/anode buffer layer (ABL)/copper phthalocyanine (CuPc)/fullerene/bathocuproine/Ag structure. An ultrathin Ag ABL and ultraviolet (UV)-ozone treatment of ITO independently improve the durability of OSCs against illumination stress. The thin pentacene ABL provides good ohmic contact between the ITO and the CuPc layer, thereby producing a large short-circuit current. The combined use of the abovementioned three modifications collectively achieves both better initial performance and durability against illumination stress.

KSC-03pd0150

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - In the Multi-Purpose Processing Facility, the Pegasus launch vehicle is ready for installation of the Solar Radiation and Climate Experiment (SORCE) satellite. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0159

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - Both the Pegasus XL launch vehicle (left) and the Solar Radiation and Climate Experiment (SORCE) satellite are seen prior to encapsulation and installation. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0166

NASA Image and Video Library

2003-01-22

KENNEDY SPACE CENTER, FLA. - The Pegasus XL launch vehicle, with the Solar Radiation and Climate Experiment (SORCE) satellite aboard, is ready for transfer to Cape Canaveral Air Force Station (CCAFS), Fla. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from CCAFS. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0169

NASA Image and Video Library

2003-01-22

KENNEDY SPACE CENTER, FLA. - The Pegasus XL launch vehicle, with the Solar Radiation and Climate Experiment (SORCE) satellite aboard, arrives at Cape Canaveral Air Force Station (CCAFS), Fla. SORCE, built by Orbital Sciences Corporation (OSC), will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from CCAFS. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral..

KSC-03pd0167

NASA Image and Video Library

2003-01-22

KENNEDY SPACE CENTER, FLA. - The Pegasus XL launch vehicle, with the Solar Radiation and Climate Experiment (SORCE) satellite aboard, is ready for transfer to Cape Canaveral Air Force Station (CCAFS), Fla. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from CCAFS. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0161

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - The second half of the fairing is moved toward the Solar Radiation and Climate Experiment (SORCE) satellite (left). Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla., from a Pegasus XL launch vehicle. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

Charge transport in liquid crystalline smectic and discotic organic semiconductors: New results and experimental methodologies

NASA Astrophysics Data System (ADS)

Paul, Sanjoy

Organic electronics offer the possibility of producing low cost, flexible, and large area electronics. Organic semiconductors (OSCs) (organic polymers and crystals), used in organic electronics, are promising materials for novel optical and electronic devices such as organic light emitting diodes, organic field effect transistors, organic sensors, and organic photovoltaics (OPVs). OSCs are composed of molecules weakly held together via van der Walls forces rather than covalent bonds as in the case of inorganic semiconductors such as Si. The combined effect of small wave function overlap, spatial and energetic disorder in organic semiconducting materials lead to localization of charge carriers and, in many cases, hopping conduction. OSCs also differ from conventional semiconductors in that charges photogeneration (e.g., in OPVs) proceeds via the production, diffusion, and dissociation of excitons. Liquid crystalline OSCs (LCOSCs) are semiconductors with phases intermediate between the highly ordered crystalline and completely disordered liquid phases. These materials offer many advantages including facile alignment and the opportunity to study the effects of differing intermolecular geometries on transfer integrals, disorder-induced trapping, charge mobilities, and photogeneration efficiency. In this dissertation work, we explored the photogeneration and charge transport mechanisms in a few model smectic and discotic LCs to better understand the governing principles of photogeneration and charge transport using conventional and novel methods based on the pulsed laser time-of-flight charge carrier transport technique. Four major interrelated topics were considered in this research. First, a sample of smectic LC was aligned in order to compare the resulting hole mobility to that of an unaligned sample, with the aim of understanding how the intermolecular alignment over large length scales affects the hopping probability. The role of the polarization of the

In vitro differentiation of human oocyte-like cells from oogonial stem cells: single-cell isolation and molecular characterization.

PubMed

Silvestris, Erica; Cafforio, Paola; D'Oronzo, Stella; Felici, Claudia; Silvestris, Franco; Loverro, Giuseppe

2018-01-03

Are the large cells derived from cultured DEAD box polypeptide 4 (DDX4)-positive oogonial stem cells (OSCs), isolated from the ovarian cortex of non-menopausal and menopausal women, oocyte-like cells? Under appropriate culture conditions, DDX4-positive OSCs from non-menopausal and menopausal women differentiate into large haploid oocyte-like cells expressing the major oocyte markers growth differentiation factor 9 (GDF-9) and synaptonemal complex protein 3 (SYCP3) and then enter meiosis. The recent reports of OSCs in the ovaries of non-menopausal and menopausal women suggest that neo-oogenesis is inducible during ovarian senescence. However, several questions remain regarding the isolation of these cells, their spontaneous maturation in vitro, and the final differentiation state of the resulting putative oocytes. DDX4-positive OSCs were obtained from 19 menopausal and 13 non-menopausal women (who underwent hysterectomy for uterine fibroma, ovarian cyst, or other benign pathologies) and cultured for up to 3 weeks. Large and small cells were individually isolated and typed for early and late differentiation markers. Ovarian cortex fragments were processed by immuno-magnetic separation using a rabbit anti-human DDX4 antibody and the positive populations were measured by assessing both FRAGILIS and stage-specific embryonic antigen 4 (SSEA-4) expression. After 3 weeks in culture, large oocyte-like cells were individually isolated by DEPArray based on PKH26 red staining and cell size determination. GDF-9 and SYCP3 as final, and developmental pluripotency-associated protein 3 (DPPA3) as primordial, germline markers were measured by droplet digital PCR. The haploid versus diploid chromosomal content of chromosomes X and 5 was investigated using fluorescence in situ hybridization (FISH). SSEA-4+ and FRAGILIS+ subsets of DDX4-positive populations were present at lower mean levels in menopausal (SSEA-4+: 46.7%; FRAGILIS+: 47.5%) than in non-menopausal (SSEA-4+: 64

Effects of ray profile modeling on resolution recovery in clinical CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hofmann, Christian; Knaup, Michael; Kachelrieß, Marc, E-mail: marc.kachelriess@dkfz-heidelberg.de

2014-02-15

Purpose: Iterative image reconstruction gains more and more interest in clinical routine, as it promises to reduce image noise (and thereby patient dose), to reduce artifacts, or to improve spatial resolution. However, among vendors and researchers, there is no consensus of how to best achieve these goals. The authors are focusing on the aspect of geometric ray profile modeling, which is realized by some algorithms, while others model the ray as a straight line. The authors incorporate ray-modeling (RM) in nonregularized iterative reconstruction. That means, instead of using one simple single needle beam to represent the x-ray, the authors evaluatemore » the double integral of attenuation path length over the finite source distribution and the finite detector element size in the numerical forward projection. Our investigations aim at analyzing the resolution recovery (RR) effects of RM. Resolution recovery means that frequencies can be recovered beyond the resolution limit of the imaging system. In order to evaluate, whether clinical CT images can benefit from modeling the geometrical properties of each x-ray, the authors performed a 2D simulation study of a clinical CT fan-beam geometry that includes the precise modeling of these geometrical properties. Methods: All simulations and reconstructions are performed in native fan-beam geometry. A water phantom with resolution bar patterns and a Forbild thorax phantom with circular resolution patterns representing calcifications in the heart region are simulated. An FBP reconstruction with a Ram–Lak kernel is used as a reference reconstruction. The FBP is compared to iterative reconstruction techniques with and without RM: An ordered subsets convex (OSC) algorithm without any RM (OSC), an OSC where the forward projection is modeled concerning the finite focal spot and detector size (OSC-RM) and an OSC with RM and with a matched forward and backprojection pair (OSC-T-RM, T for transpose). In all cases, noise was

Nanoscale characterization of the electrical properties of oxide electrodes at the organic semiconductor-oxide electrode interface in organic solar cells

NASA Astrophysics Data System (ADS)

MacDonald, Gordon Alex

This dissertation focuses on characterizing the nanoscale and surface averaged electrical properties of transparent conducting oxide electrodes such as indium tin oxide (ITO) and transparent metal-oxide (MO) electron selective interlayers (ESLs), such as zinc oxide (ZnO), the ability of these materials to rapidly extract photogenerated charges from organic semiconductors (OSCs) used in organic photovoltaic (OPV) cells, and evaluating their impact on the power conversion efficiency (PCE) of OPV devices. In Chapter 1, we will introduce the fundamental principles, benefits, and the key innovations that have advanced this technology. In Chapter 2 of this dissertation, we demonstrate an innovative application of conductive probe atomic force microscopy (CAFM) to map the nanoscale electrical heterogeneity at the interface between ITO, and a well-studied OSC, copper phthalocyanine (CuPc).(MacDonald et al. (2012) ACS Nano, 6, p. 9623) In this work we collected arrays of current-voltage (J-V) curves, using a CAFM probe as the top contact of CuPc/ITO systems, to map the local J-V responses. By comparing J-V responses to known models for charge transport, we were able to determine if the local rate-limiting-step for charge transport is through the OSC (ohmic) or the CuPc/ITO interface (non-ohmic). Chapter 3 focus on the electrical property characterization of RF-magnetron sputtered ZnO (sp-ZnO) ESL films on ITO substrates. We have shown that the energetic alignment of ESLs and the OSC active materials plays a critical role in determining the PCE of OPV devices and UV light soaking sensitivity. We have used a combination of device testing, modeling, and impedance spectroscopy to characterize the effects that energetic alignment has on the charge carrier transport and distribution within the OPV device. In Chapter 4 we demonstrate that the local properties of sp-ZnO films varies as a function of the underlying ITO crystal face. We show that the local ITO crystal face determines

System matrix computation vs storage on GPU: A comparative study in cone beam CT.

PubMed

Matenine, Dmitri; Côté, Geoffroi; Mascolo-Fortin, Julia; Goussard, Yves; Després, Philippe

2018-02-01

Iterative reconstruction algorithms in computed tomography (CT) require a fast method for computing the intersection distances between the trajectories of photons and the object, also called ray tracing or system matrix computation. This work focused on the thin-ray model is aimed at comparing different system matrix handling strategies using graphical processing units (GPUs). In this work, the system matrix is modeled by thin rays intersecting a regular grid of box-shaped voxels, known to be an accurate representation of the forward projection operator in CT. However, an uncompressed system matrix exceeds the random access memory (RAM) capacities of typical computers by one order of magnitude or more. Considering the RAM limitations of GPU hardware, several system matrix handling methods were compared: full storage of a compressed system matrix, on-the-fly computation of its coefficients, and partial storage of the system matrix with partial on-the-fly computation. These methods were tested on geometries mimicking a cone beam CT (CBCT) acquisition of a human head. Execution times of three routines of interest were compared: forward projection, backprojection, and ordered-subsets convex (OSC) iteration. A fully stored system matrix yielded the shortest backprojection and OSC iteration times, with a 1.52× acceleration for OSC when compared to the on-the-fly approach. Nevertheless, the maximum problem size was bound by the available GPU RAM and geometrical symmetries. On-the-fly coefficient computation did not require symmetries and was shown to be the fastest for forward projection. It also offered reasonable execution times of about 176.4 ms per view per OSC iteration for a detector of 512 × 448 pixels and a volume of 384 3 voxels, using commodity GPU hardware. Partial system matrix storage has shown a performance similar to the on-the-fly approach, while still relying on symmetries. Partial system matrix storage was shown to yield the lowest relative

Segmentation and Contrasting Magma Supply Along the South-East Indian Ridge, 130°E to 140°E: Results of the STORM Cruise

NASA Astrophysics Data System (ADS)

Briais, A.; Ruellan, E.; Maia, M.; Hemond, C.; Hanan, B. B.; Ceuleneer, G.; Graham, D. W.; Park, S. H.

2017-12-01

We present observations of the South-East Indian Ridge (SEIR) between 130°E to 140°E, mostly collected during the STORM cruise (South Tasmania Ocean Ridge and Mantle) on the N/O L'Atalante. The SEIR displays large variations of axial depth despite an almost constant intermediate full spreading rate of 75 km/m.y. In the study area the analysis of multibeam bathymetry maps shows that the axis displays a rise morphology to the east away from the discontinuities, and a rifted high morphology in the west and near the OSCs, as often observed along intermediate-spreading mid-ocean ridges. The ridge axis is offset by 27 km at 131°E and 20 km at 135°E by two large-offset overlapping spreading centers (OSCs) propagating westward, and by a smaller OSC at 137°17'E. These OSCs define four second-order ridge segments (A2 to A5 from west to east). We observe a general shallowing of the ridge axis from 3100 m depth in the west to 2400 m depth in the east, and a prominent deepening of the axis near the large OSCs. The easternmost segment A5 shows a very shallow axial ridge suggesting a robust magma supply despite its proximity to the George V transform fault (140°E). Major element variations in basalt glasses are systematically related to morphotectonic segmentation of the ridge axis, showing contrasts in crystal fractionation from one segment to another that may relate to differences in replenishment of axial melt lenses by primitive melts. Along segment A5, crystallization increases with proximity to the George V transform fault, consistent with an expected cold edge effect. In contrast, along segment A3 the extent of crystallization increases progressively from east to west in the direction of ridge propagation. *STORM Cruise Scientific Party: F. Barrere, C. Boulart, A. Briais, D. Brunelli, G. Ceuleneer, N. Ferreira, D. Graham, B. Hanan, C. Hémond, S. Macleod, M. Maia, A. Maillard, S. Merkuryev, S.H. Park, S. Révillon, E. Ruellan, A. Schohn, S. Watson, and Y.S. Yang.

Are the General Medical Council's Tests of Competence fair to long standing doctors? A retrospective cohort study.

PubMed

Mehdizadeh, Leila; Sturrock, Alison; Dacre, Jane

2015-04-21

The General Medical Council's Fitness to Practise investigations may involve a test of competence for doctors with performance concerns. Concern has been raised about the suitability of the test format for doctors who qualified before the introduction of Single Best Answer and Objective Structured Clinical Examination assessments, both of which form the test of competence. This study explored whether the examination formats used in the tests of competence are fair to long standing doctors who have undergone fitness to practise investigation. A retrospective cohort design was used to determine an association between year of primary medical qualification and doctors' test of competence performance. Performance of 95 general practitioners under investigation was compared with a group of 376 volunteer doctors. We analysed performance on knowledge test, OSCE overall, and three individual OSCE stations using Spearman's correlation and regression models. Doctors under investigation performed worse on all test outcomes compared to the comparison group. Qualification year correlated positively with performance on all outcomes except for physical examination (e.g. knowledge test r = 0.48, p < 0.001 and OSCE r = 0.37, p < 0.001). Qualification year was associated with test performance in doctors under investigation even when controlling for sex, ethnicity and qualification region. Regression analyses showed that qualification year was associated with knowledge test, OSCE and communication skills performance of doctors under investigation when other variables were controlled for. Among volunteer doctors this was not the case and their performance was more strongly related to where they qualified and their ethnic background. Furthermore, volunteer doctors who qualified before the introduction of Single Best Answer and OSCE assessments, still outperformed their peers under investigation. Earlier graduates under fitness to practise investigation performed less

Measurement of the levels anxiety, self-perception of preparation and expectations for success using an objective structured clinical examination, a written examination, and a preclinical preparation test in Kerman dental students.

PubMed

Kalantari, Mahsa; Zadeh, Nazila Lashkari; Agahi, Raha Habib; Navabi, Nader; Hashemipour, Maryam Alsadat; Nassab, Amir Hossein Gandjalikhan

2017-01-01

Examinations have an important role in evaluating students' learning outcomes and their mastery of a subject. Passing or failing an examination can have far-reaching consequences for the students. Therefore, it is not surprising that international studies consistently show that dental students report examinations and grades among the highest ranking stressors in dental schools. The aim of this research was to measure the levels of anxiety, self-perception of preparation and expectations for success using an objective structured clinical examination (OSCE), a written examination and a preclinical preparation test, and to examine the effects of the three predictive variables on the outcomes of assessments. The present research is a cross-sectional study. The population under consideration was students of Kerman Dental School in 2013. Examination anxiety was measured with Spielberger's state anxiety inventory. Preparation for the assessment (I am fully prepared = 4, I am prepared = 3, I'm not prepared = 2, I'm not fully prepared = 1) and expectation to succeed (I am quite successful = 4, I am successful = 3, I'm not successful = 2, I'm not quite successful = 1) were quantified with Likert scale. The questionnaire was completed during an OSCE, a written examination, a preclinical crown and bridge preparation test and a nonexamination situation. The study population consisted of 138 4 th , 5 th , and 6 th year Kerman dental students (65 males and 73 females). The results showed that all the assessment methods induced a significant increase in state anxiety compared to baseline levels with the highest anxiety levels reported during an OSCE (62.4 ± 8.1, P = 0.04) and a written examination (48.8 ± 9.2, P = 0.04). The preparation levels in females were significantly higher than those in males in OSCE ( P = 0.03) and written ( P = 0.04). State anxiety was high in all the three assessment methods. OSCE induced more anxiety than other assessment formats. However, anxiety was

Ovarian stem cells are always accompanied by very small embryonic-like stem cells in adult mammalian ovary.

PubMed

Bhartiya, Deepa

2015-11-05

Existing dogma that a female is born with fixed number of eggs was challenged by the detection of stem cells in adult mammalian ovary. Data has accumulated in support of ovarian stem cells (OSCs) proliferation, maintenance in culture, formation of germ cell nests and differentiation into oocytes and primordial follicle assembly using different strategies. Flow cytometry analysis identified >8 μm OSCs which are DDX1 positive and are considered equivalent to spermatogonial stem cells (SSCs) in testis. Analysis of both ovarian and testicular smears obtained after enzymatic digestion has led to the identification of an additional stem cell population termed very small embryonic-like stem cells (VSELs). VSELs and OSCs/SSCs differ from each other in their size and OCT-4 expression. VSELs express pluripotent markers including nuclear OCT-4 whereas OSCs/SSCs express cytoplasmic OCT-4 suggesting a differentiated state. VSELs can be studied by flow cytometry as small sized cells which are LIN-/CD45-/Sca-1+. We have reported 0.02 ± 0.008, 0.03 ± 0.017 and 0.08 ± 0.03 % of total cells as VSELs in normal, chemoablated and after FSH treatment to chemoablated mouse ovary. VSELs have remained poorly studied till now because of their very small size and rare occurrence. Spinning cells obtained after enzymatic digestion of ovarian tissue at a speed of 1000G (rather than 1200 rpm) throughout processing allows reliable detection of the VSELs by flow cytometry. VSELs exist in aged, chemoablated and non-functional ovary and providing a healthy niche to support their function offers an interesting strategy to manage infertility.

Flipped Learning: Can Rheumatology Lead the Shift in Medical Education?

PubMed

El Miedany, Yasser; El Gaafary, Maha; El Aroussy, Nadia; Youssef, Sally

2018-04-16

To: 1. implement flipped classroom rheumatology teaching for undergraduate education. 2. Evaluate outcomes of teaching using OSCE assessment and student perceived effectiveness and satisfaction survey. The flipped classroom education was conducted in 3 phases. Phase 1: carried out in the students' own time. Web links were emailed to assist exposure of the instructional part of the lesson online. Phase 2: interactive in-class activity to share personal reflection and reinforce the key aspects. Phase 3: a simulated OSCE assessment. A cohort of 56-students, who were taught in the last educational year on the same topics according to standard teaching protocols, were included as control group. The clinical Outcomes were assessed using the scores of the OSCE examination model. Academic outcomes included the engagement measure as well as the students' answers to perceived effectiveness and satisfaction survey. There was no significant difference regarding demographics between the 2 students' groups. There was significant improvement (p< 0.05) in the flipped learning, in contrast to the control group, in terms of clinical (OSCE score) as well as communication skills. Student perceived effectiveness and satisfaction was significantly higher among the flipped learning (p< 0.05). Scores from the flipped learning cohort showed a state of engagement significantly higher than the control group (p< 0.01). Flipped learning implementation musculoskeletal learning successfully demonstrated a promising platform for using technology to make better use of the students' time, and for increasing their satisfaction. Active learning increases student engagement and can lead to improved retention of knowledge. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Oligothiophene-Indandione-Linked Narrow-Band Gap Molecules: Impact of π-Conjugated Chain Length on Photovoltaic Performance.

PubMed

Komiyama, Hideaki; To, Takahiro; Furukawa, Seiichi; Hidaka, Yu; Shin, Woong; Ichikawa, Takahiro; Arai, Ryota; Yasuda, Takuma

2018-04-04

Solution-processed organic solar cells (OSCs) based on narrow-band gap small molecules hold great promise as next-generation energy-converting devices. In this paper, we focus on a family of A-π-D-π-A-type small molecules, namely, BDT- nT-ID ( n = 1-4) oligomers, consisting of benzo[1,2- b:4,5- b']dithiophene (BDT) as the central electron-donating (D) core, 1,3-indandione (ID) as the terminal electron-accepting (A) units, and two regioregular oligo(3-hexylthiophene)s ( nT) with different numbers of thiophene rings as the π-bridging units, and elucidate their structure-property-function relationships. The effects of the length of the π-bridging nT units on the optical absorption, thermal behavior, morphology, hole mobility, and OSC performance were systematically investigated. All oligomers exhibited broad and intense visible photoabsorption in the 400-700 nm range. The photovoltaic performances of bulk heterojunction OSCs based on BDT- nT-IDs as donors and a fullerene derivative as an acceptor were studied. Among these oligomers, BDT-2T-ID, incorporating bithiophene as the π-bridging units, showed better photovoltaic performance with a maximum power conversion efficiency as high as 6.9% under AM 1.5G illumination without using solvent additives or postdeposition treatments. These favorable properties originated from the well-developed interpenetrating network morphology of BDT-2T-ID, with larger domain sizes in the photoactive layer. Even though all oligomers have the same A-D-A main backbone, structural modulation of the π-bridging nT length was found to impact their self-organization and nanostructure formation in the solid state, as well as the corresponding OSC device performance.

Using Technology to Enhance Teaching of Patient-Centered Interviewing for Early Medical Students.

PubMed

Kaltman, Stacey; Talisman, Nicholas; Pennestri, Susan; Syverson, Eleri; Arthur, Paige; Vovides, Yianna

2018-06-01

Effective strategies for teaching communication skills to health professions students are needed. This article describes the design and evaluation of immersive and interactive video simulations for medical students to practice basic communication skills. Three simulations were developed, focusing on patient-centered interviewing techniques such as using open-ended questions, reflections, and empathic responses while assessing a patient's history of present illness. First-year medical students were randomized to simulation or education-as-usual arms. Students in the simulation arm were given access to three interactive video simulations developed using Articulate Storyline, an e-learning authoring tool, to practice and receive feedback on patient-centered interviewing techniques to prepare for their Observed Structured Clinical Examination (OSCE). Trained raters evaluated videos of two OSCE cases for each participant to assess specific communication skills used during the history of present illness component of the interview. Eighty-seven percent of the students in the simulation arm interacted with at least one simulation during the history of present illness. For both OSCE cases, students in the simulation arm asked significantly more open-ended questions. Students in the simulation arm asked significantly fewer closed-ended questions and offered significantly more empathic responses in one OSCE case. No differences were found for reflections. Students reported that the simulations helped improve their communication skills. The use of interactive video simulations was found to be feasible to incorporate into the curriculum and was appealing to students. In addition, students in the simulation arm displayed more behaviors consistent with the patient-centered interviewing model practiced in the simulations. Continued development and research are warranted.

Rational pharmacotherapy training for fourth-year medical students.

PubMed

Gelal, Ayse; Gumustekin, Mukaddes; Arici, M Aylin; Gidener, Sedef

2013-01-01

In this study we aimed to evaluate the impact of Rational Pharmacotherapy (RPT) course program, reinforced by video footages, on the rational pharmacotherapy skills of the students. RPT course program has been conducted in Dokuz Eylul University School of Medicine since 2008/9. The course has been organised in accordance with World Health Organisation (WHO) Good Prescribing Guide. The aim of the course was to improve the problem solving skills (methodology for selection of the (p)ersonel-drug, prescription writing and informing patient about his illness and drugs) and communication skills of students. The impact of the course has been measured by pre/post-test design by an objective structured clinical examination (OSCE). In academic year 2010/11, to further improve OSCE score of the students we added doctor-patient communication video footages to the RPT course programme. During training, the students were asked to evaluate the doctor-patient communication and prescription on two video footages using a checklist followed by group discussions. Total post-test OSCE score was significantly higher for 2010/11 academic year students (n = 147) than it was for 2009/10 year students (n = 131). The 2010/11 academic year students performed significantly better than the 2009/10 academic year students on four steps of OSCE. These steps were "defining the patient's problem", "specifying the therapeutic objective", "specifying the non-pharmacological treatment" and "choosing a (drug) treatment, taking all relevant patient characteristics into account". The present study demonstrated that the implementation of video footages and group discussions to WHO/Good Prescribing Method improved the fourth-year medical students' performance in rational pharmacotherapy skills.

Correlating highpower conversion efficiency of PTB7:PC 71BM inverted organic solar cells with nanoscale structures [Unraveling the correlation between the structural aspects and power conversion efficiency in PTB7:PC 71BM inverted organic solar cells

DOE PAGES

Das, Sanjib; Browning, Jim; Gu, Gong; ...

2015-07-16

Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC 71BM as the active layer and poly-[(9,9-bis(3 -( N,N-dimethylamino)propyl)-2,7-fluorene)- alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surfacemore » modifying layer. We have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC 71BM into the PFN layer, resulting in improved electron transport. The PC 71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. Furthermore, the DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC 71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.« less

Lifestyle medicine curriculum for a preventive medicine residency program: implementation and outcomes.

PubMed

Nawaz, Haq; Petraro, Paul V; Via, Christina; Ullah, Saif; Lim, Lionel; Wild, Dorothea; Kennedy, Mary; Phillips, Edward M

2016-01-01

The vast majority of the healthcare problems burdening our society today are caused by disease-promoting lifestyles (e.g., physical inactivity and unhealthy eating). Physicians report poor training and lack of confidence in counseling patients on lifestyle changes. To evaluate a new curriculum and rotation in lifestyle medicine for preventive medicine residents. Training included didactics (six sessions/year), distance learning, educational conferences, and newly developed lifestyle medicine rotations at the Institute of Lifestyle Medicine, the Yale-Griffin Prevention Research Center, and the Integrative Medicine Center. We used a number of tools to assess residents' progress including Objective Structured Clinical Examinations (OSCEs), self-assessments, and logs of personal health habits. A total of 20 residents participated in the lifestyle medicine training between 2010 and 2013. There was a 15% increase in residents' discussions of lifestyle issues with their patients based on their baseline and follow-up surveys. The performance of preventive medicine residents on OSCEs increased each year they were in the program (average OSCE score: PGY1 73%, PGY2 83%, PGY3 87%, and PGY4 91%, p=0.01). Our internal medicine and preliminary residents served as a control, since they did participate in didactics but not in lifestyle medicine rotations. Internal medicine and preliminary residents who completed the same OSCEs had a slightly lower average score (76%) compared with plural for resident, preventive medicine residents (80%). However, this difference did not reach statistical significance (p=0.11). Incorporating the lifestyle medicine curriculum is feasible for preventive medicine training allowing residents to improve their health behavior change discussions with patients as well as their own personal health habits.

Identification of Putative Genes Involved in Limonoids Biosynthesis in Citrus by Comparative Transcriptomic Analysis

PubMed Central

Wang, Fusheng; Wang, Mei; Liu, Xiaona; Xu, Yuanyuan; Zhu, Shiping; Shen, Wanxia; Zhao, Xiaochun

2017-01-01

Limonoids produced by citrus are a group of highly bioactive secondary metabolites which provide health benefits for humans. Currently there is a lack of information derived from research on the genetic mechanisms controlling the biosynthesis of limonoids, which has limited the improvement of citrus for high production of limonoids. In this study, the transcriptome sequences of leaves, phloems and seeds of pummelo (Citrus grandis (L.) Osbeck) at different development stages with variances in limonoids contents were used for digital gene expression profiling analysis in order to identify the genes corresponding to the biosynthesis of limonoids. Pair-wise comparison of transcriptional profiles between different tissues identified 924 differentially expressed genes commonly shared between them. Expression pattern analysis suggested that 382 genes from three conjunctive groups of K-means clustering could be possibly related to the biosynthesis of limonoids. Correlation analysis with the samples from different genotypes, and different developing tissues of the citrus revealed that the expression of 15 candidate genes were highly correlated with the contents of limonoids. Among them, the cytochrome P450s (CYP450s) and transcriptional factor MYB demonstrated significantly high correlation coefficients, which indicated the importance of those genes on the biosynthesis of limonoids. CiOSC gene encoding the critical enzyme oxidosqualene cyclase (OSC) for biosynthesis of the precursor of triterpene scaffolds was found positively corresponding to the accumulation of limonoids during the development of seeds. Suppressing the expression of CiOSC with VIGS (Virus-induced gene silencing) demonstrated that the level of gene silencing was significantly correlated to the reduction of limonoids contents. The results indicated that the CiOSC gene plays a pivotal role in biosynthesis of limonoids. PMID:28553308

Lifestyle medicine curriculum for a preventive medicine residency program: implementation and outcomes

PubMed Central

Nawaz, Haq; Petraro, Paul V.; Via, Christina; Ullah, Saif; Lim, Lionel; Wild, Dorothea; Kennedy, Mary; Phillips, Edward M.

2016-01-01

Background The vast majority of the healthcare problems burdening our society today are caused by disease-promoting lifestyles (e.g., physical inactivity and unhealthy eating). Physicians report poor training and lack of confidence in counseling patients on lifestyle changes. Objective To evaluate a new curriculum and rotation in lifestyle medicine for preventive medicine residents. Methods Training included didactics (six sessions/year), distance learning, educational conferences, and newly developed lifestyle medicine rotations at the Institute of Lifestyle Medicine, the Yale-Griffin Prevention Research Center, and the Integrative Medicine Center. We used a number of tools to assess residents’ progress including Objective Structured Clinical Examinations (OSCEs), self-assessments, and logs of personal health habits. Results A total of 20 residents participated in the lifestyle medicine training between 2010 and 2013. There was a 15% increase in residents’ discussions of lifestyle issues with their patients based on their baseline and follow-up surveys. The performance of preventive medicine residents on OSCEs increased each year they were in the program (average OSCE score: PGY1 73%, PGY2 83%, PGY3 87%, and PGY4 91%, p=0.01). Our internal medicine and preliminary residents served as a control, since they did participate in didactics but not in lifestyle medicine rotations. Internal medicine and preliminary residents who completed the same OSCEs had a slightly lower average score (76%) compared with plural for resident, preventive medicine residents (80%). However, this difference did not reach statistical significance (p=0.11). Conclusion Incorporating the lifestyle medicine curriculum is feasible for preventive medicine training allowing residents to improve their health behavior change discussions with patients as well as their own personal health habits. PMID:27507540

Pursuing Polymer Dielectric Interfacial Effect in Organic Transistors for Photosensing Performance Optimization.

PubMed

Wu, Xiaohan; Chu, Yingli; Liu, Rui; Katz, Howard E; Huang, Jia

2017-12-01

Polymer dielectrics in organic field-effect transistors (OFETs) are essential to provide the devices with overall flexibility, stretchability, and printability and simultaneously introduce charge interaction on the interface with organic semiconductors (OSCs). The interfacial effect between various polymer dielectrics and OSCs significantly and intricately influences device performance. However, understanding of this effect is limited because the interface is buried and the interfacial charge interaction is difficult to stimulate and characterize. Here, this challenge is overcome by utilizing illumination to stimulate the interfacial effect in various OFETs and to characterize the responses of the effect by measuring photoinduced changes of the OFETs performances. This systemic investigation reveals the mechanism of the intricate interfacial effect in detail, and mathematically explains how the photosensitive OFETs characteristics are determined by parameters including polar group of the polymer dielectric and the OSC side chain. By utilizing this mechanism, performance of organic electronics can be precisely controlled and optimized. OFETs with strong interfacial effect can also show a signal additivity caused by repeated light pulses, which is applicable for photostimulated synapse emulator. Therefore, this work enlightens a detailed understanding on the interface effect and provides novel strategies for optimizing OFET photosensory performances.

Virtual study groups and online Observed Structured Clinical Examinations practices - enabling trainees to enable themselves.

PubMed

Davidson, Dennisa; Evans, Lois

2018-03-01

To explore online study groups as augmentation tools in preparing for the Royal Australian and New Zealand College of Psychiatrists Observed Structured Clinical Examinations (OSCE) for fellowship. An online survey of New Zealand trainees was carried out to assess exam preparedness and openness to virtual study groups and results analysed. Relevant material around virtual study groups for fellowship examinations was reviewed and used to inform a pilot virtual study group. Four New Zealand trainees took part in the pilot project, looking at using a virtual platform to augment OSCE preparation. Of the 50 respondents 36% felt adequately prepared for the OSCE. Sixty-four per cent were interested in using a virtual platform to augment their study. Virtual study groups were noted to be especially important for rural trainees, none of whom felt able to form study groups for themselves. The pilot virtual study group was trialled successfully. All four trainees reported the experience as subjectively beneficial to their examination preparation. Virtual platforms hold promise as an augmentation strategy for exam preparation, especially for rural trainees who are more geographically isolated and less likely to have peers preparing for the same examinations.

A helical perylene diimide-based acceptor for non-fullerene organic solar cells: synthesis, morphology and exciton dynamics

NASA Astrophysics Data System (ADS)

Chen, Li; Wu, Mingliang; Shao, Guangwei; Hu, Jiahua; He, Guiying; Bu, Tongle; Yi, Jian-Peng; Xia, Jianlong

2018-05-01

Helical perylene diimide-based (hPDI) acceptors have been established as one of the most promising candidates for non-fullerene organic solar cells (OSCs). In this work, we report a novel hPDI-based molecule, hPDI2-CN2, as an electron acceptor for OSCs. Combining the hPDI2-CN2 with a low-bandgap polymeric donor (PTB7-Th), the blending film morphology exhibited high sensitivity to various treatments (such as thermal annealing and addition of solvent additives), as evidenced by atomic force microscope studies. The power conversion efficiency (PCE) was improved from 1.42% (as-cast device) to 2.76% after thermal annealing, and a PCE of 3.25% was achieved by further addition of 1,8-diiodooctane (DIO). Femtosecond transient absorption (TA) spectroscopy studies revealed that the improved thin-film morphology was highly beneficial for the charge carrier transport and collection. And a combination of fast exciton diffusion rate and the lowest recombination rate contributed to the best performance of the DIO-treated device. This result further suggests that the molecular conformation needs to be taken into account in the design of perylene diimide-based acceptors for OSCs.

Assessment of email communication skills of rheumatology fellows: a pilot study

PubMed Central

Dhuper, Sonal; Siva, Chokkalingam; Fresen, John L; Petruc, Marius; Velázquez, Celso R

2010-01-01

Physician–patient email communication is gaining popularity. However, a formal assessment of physicians' email communication skills has not been described. We hypothesized that the email communication skills of rheumatology fellows can be measured in an objective structured clinical examination (OSCE) setting using a novel email content analysis instrument which has 18 items. During an OSCE, we asked 50 rheumatology fellows to respond to a simulated patient email. The content of the responses was assessed using our instrument. The majority of rheumatology fellows wrote appropriate responses scoring a mean (±SD) of 10.6 (±2.6) points (maximum score 18), with high inter-rater reliability (0.86). Most fellows were concise (74%) and courteous (68%) but not formal (22%). Ninety-two percent of fellows acknowledged that the patient's condition required urgent medical attention, but only 30% took active measures to contact the patient. No one encrypted their messages. The objective assessment of email communication skills is possible using simulated emails in an OSCE setting. The variable email communication scores and incidental patient safety gaps identified, suggest a need for further training and defined proficiency standards for physicians' email communication skills. PMID:20962134

Problematizing the concept of the "borderline" group in performance assessments.

PubMed

Homer, Matt; Pell, Godfrey; Fuller, Richard

2017-05-01

Many standard setting procedures focus on the performance of the "borderline" group, defined through expert judgments by assessors. In performance assessments such as Objective Structured Clinical Examinations (OSCEs), these judgments usually apply at the station level. Using largely descriptive approaches, we analyze the assessment profile of OSCE candidates at the end of a five year undergraduate medical degree program to investigate the consistency of the borderline group across stations. We look specifically at those candidates who are borderline in individual stations, and in the overall assessment. While the borderline group can be clearly defined at the individual station level, our key finding is that the membership of this group varies considerably across stations. These findings pose challenges for some standard setting methods, particularly the borderline group and objective borderline methods. They also suggest that institutions should ensure appropriate conjunctive rules to limit compensation in performance between stations to maximize "diagnostic accuracy". In addition, this work highlights a key benefit of sequential testing formats in OSCEs. In comparison with a traditional, single-test format, sequential models allow assessment of "borderline" candidates across a wider range of content areas with concomitant improvements in pass/fail decision-making.

Using mixed solvent and changing spin-coating parameters to increase the efficiency and lifetime of organic solar cells.

PubMed

Tsai, Yu Sheng; Chu, Wei-Ping; Tang, Rong-Ming; Juang, Fuh-Shyang; Chang, Ming-Hua; Liu, Mark O; Hsieh, Tsung-Eong

2008-10-01

The derivative of C60, i.e., PCBM, and P3HT (3-hexylthiophene) were dissolved in chloroform:dichlorobenzene mixed solvent, then spin-coated as the active layer for organic solar cells (OSC). The experimental parameters were studied carefully to obtain the optimum power conversion efficiency (PCE), including the solvent mixing ratio, spin-coating speed, annealing conditions for the active layer, etc. The OSC devices were packaged with glass and a newly developed UV-glue to improve the lifetime and PCE. Dichlorobenzene solvent has great effect upon the PCE. Changing the spin-coating speed and increasing the number of steps increased the PCE apparently to 1.4%.

Mesure du Deplacement de Frequence au Maximum de la Raie P20 un Laser CO2 a Ondes Guidees (Measurement of the Frequency Shift at the Peak of the P20 Line of a CO2 Waveguide Laser),

DTIC Science & Technology

1986-06-01

VINCENT ET AL . UNCLASSIFIED JUN 86 DREV-4419/86 F/G 28/5 NI iiiimEEmmomEEI 111-25 W1.6 * AD-A170 318 WIAI iLL. f.Pf I)E V jP ’)MEN, fFIlA 4 H l t A 4...triangulaires Hewlett-Packard, modale 3310B (OSC. 1), dont le signal est amplifi6 par un amplificateur haute ten- sion Lansing, modale 80.315 (PZT AL ...CLASSIFICATION 3 PT AL O.G AL CONTROLE * OSC’ I V-~ ----- GAZ 05; C. - - SPEC-. I -_ _ - - 0 G. -ET SYNC 2 REF. - L - BP -- CSPEC 2 - DET. PYR1C - " VDET

KSC-03pd0156

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- In the Multi-Purpose Processing Facility, the Pegasus XL launch vehicle is ready for installation of the Solar Radiation and Climate Experiment (SORCE) satellite after encapsulation. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0160

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - The second half of the fairing is ready to be installed on the Solar Radiation and Climate Experiment (SORCE) satellite (at right). Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla., from a Pegasus XL launch vehicle. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0165

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- In the Multi-Purpose Processing Facility, the Pegasus XL launch vehicle is ready to be moved toward the Solar Radiation and Climate Experiment (SORCE) satellite in front of it. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0164

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- Workers in the Multi-Purpose Processing Facility look over the encapsulation of the Solar Radiation and Climate Experiment (SORCE) satellite. The satellite will next be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

5 CFR 1830.6 - Exemptions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... unfair competitive advantage or diminish the utility of established examination procedures. OSC also... prohibited personnel practice, unlawful political activity, whistleblower disclosure, Uniformed Services...

Co-functionalized organic/inorganic hybrid ZnO nanorods as electron transporting layers for inverted organic solar cells

NASA Astrophysics Data System (ADS)

Ambade, Swapnil B.; Ambade, Rohan B.; Eom, Seung Hun; Baek, Myung-Jin; Bagde, Sushil S.; Mane, Rajaram S.; Lee, Soo-Hyoung

2016-02-01

In an unprecedented attempt, we present an interesting approach of coupling solution processed ZnO planar nanorods (NRs) by an organic small molecule (SM) with a strong electron withdrawing cyano moiety and the carboxylic group as binding sites by a facile co-functionalization approach. Direct functionalization by SMs (SM-ZnO NRs) leads to higher aggregation owing to the weaker solubility of SMs in solutions of ZnO NRs dispersed in chlorobenzene (CB). A prior addition of organic 2-(2-methoxyethoxy)acetic acid (MEA) over ZnO NRs not only inhibits aggregation of SMs over ZnO NRs, but also provides enough sites for the SM to strongly couple with the ZnO NRs to yield transparent SM-MEA-ZnO NRs hybrids that exhibited excellent capability as electron transporting layers (ETLs) in inverted organic solar cells (iOSCs) of P3HT:PC60BM bulk-heterojunction (BHJ) photoactive layers. A strongly coupled SM-MEA-ZnO NR hybrid reduces the series resistance by enhancing the interfacial area and tunes the energy level alignment at the interface between the (indium-doped tin oxide, ITO) cathode and BHJ photoactive layers. A significant enhancement in power conversion efficiency (PCE) was achieved for iOSCs comprising ETLs of SM-MEA-ZnO NRs (3.64%) advancing from 0.9% for pristine ZnO NRs, while the iOSCs of aggregated SM-ZnO NRs ETL exhibited a much lower PCE of 2.6%, thus demonstrating the potential of the co-functionalization approach. The superiority of the co-functionalized SM-MEA-ZnO NRs ETL is also evident from the highest PCE of 7.38% obtained for the iOSCs comprising BHJ of PTB7-Th:PC60BM compared with extremely poor 0.05% for non-functionalized ZnO NRs.In an unprecedented attempt, we present an interesting approach of coupling solution processed ZnO planar nanorods (NRs) by an organic small molecule (SM) with a strong electron withdrawing cyano moiety and the carboxylic group as binding sites by a facile co-functionalization approach. Direct functionalization by SMs (SM

Purification, kinetics, inhibitors and CD for recombinant β-amyrin synthase from Euphorbia tirucalli L and functional analysis of the DCTA motif, which is highly conserved among oxidosqualene cyclases.

PubMed

Ito, Ryousuke; Masukawa, Yukari; Hoshino, Tsutomu

2013-03-01

β-Amyrin, a natural triterpene, is widely distributed in the plant kingdom, and its pentacyclic skeleton is produced by oxidosqualene cyclase (OSC). OSC enzymes are classified as membrane proteins, and they catalyze the polycyclization reaction of (3S)-2,3-oxidosqualene to yield nearly 150 different cyclic triterpene skeletons. To date, no report has described the successful purification and characterization of plant β-amyrin synthase. The β-amyrin synthase from Euphorbia tirucalli (EtAS) was expressed as a polyhistidine-tagged protein in Saccharomyces cerevisiae GIL77, which lacks the lanosterol synthase gene. The expression yield, determined by western blotting analysis, was 5-7 mg. By Ni(2+) -nitrilotriacetic acid affinity column chromatography and careful selection of the proper imidazole concentration during the purification processes of washing and elution, a single band was successfully obtained on SDS/PAGE. We then tested the effects of four detergents on the enzyme activity. Supplementation with Triton X-100 at a concentration of 0.05% yielded the highest activity. The optimal pH and temperature were 7.0 and 30 °C, respectively. The kinetic parameters, K(m) and k(cat) , were determined to be 33.8 ± 0.53 μm and 46.4 ± 0.68 min(-1), respectively. To the best of our knowledge, there are no reports describing both K(m) and k(cat) for OSCs except for two examples of rat and bovine lanosterol synthases. The β-amyrin synthase purified in this study showed a significantly higher catalytic efficiency (k(cat)/K(m)) (~ 10(3)-fold) than those of the two reported lanosterol synthases. Gel-filtration HPLC indicated that the OSC exists as a monomer, and the eluted OSC retained its activity. Furthermore, the inhibition constants K(i) and IC(50) and types of inhibition by iminosqualene, Ro48-8071 and U18666A were determined, and indicated that iminosqualene and Ro48-8071 are potent inhibitors. Additionally, this is the first report of the kinetic data of the

Effect of novel patient interaction on students' performance of pregnancy options counseling.

PubMed

Shaddeau, Angela; Nimz, Abigail; Sheeder, Jeanelle; Tocce, Kristina

2015-01-01

Although options counseling is a fundamental skill for medical providers, previous research has identified gaps in medical school reproductive health education. To determine if a 1-h novel patient interaction (NPI) improves student performance when caring for a standardized patient with an unintended pregnancy. From September 2012 to June 2013 we randomized third-year medical students at the University of Colorado School of Medicine to the standard curriculum plus an NPI, or the standard curriculum only. The NPI consisted of a 1-h small-group session with a patient who discussed her experiences with options counseling and her decision to terminate her pregnancy. Students completed an Objective Structured Clinical Examination (OSCE) at the rotation's end, which included options counseling. The primary outcome was the proportion of participants achieving 'excellence' on the OSCE checklist. 'Excellence' was defined as a score ≥90%. Examinations were flagged as 'unsatisfactory encounters' if core competencies were not addressed. OSCE standardized patients and evaluators were blinded to group assignment. In total, 135 students were eligible and randomized: 75 to NPI; 60 to control. During the OSCE, few students achieved 'excellence' (24% NPI vs. 28% control, p=0.57).There were no differences between scores for components of options counseling. More students in the control group 'appeared somewhat uncomfortable' delivering the pregnancy test results (5% NPI vs. 18% control, p=0.006). More than half (54%) of the intervention group and 67% of controls had 'unsatisfactory encounters' (p=0.16), almost exclusively due to omission of adoption. Most students addressed abortion (96% NPI vs. 92% control, p=0.29). A 1-h NPI does not improve medical students' performance of pregnancy options counseling and the option of adoption is routinely omitted. Adoption is clearly an area that needs greater attention when designing comprehensive reproductive health curriculum for medical

Microwave-assisted of dispersive liquid-liquid microextraction and spectrophotometric determination of uranium after optimization based on Box-Behnken design and chemometrics methods.

PubMed

Niazi, Ali; Khorshidi, Neda; Ghaemmaghami, Pegah

2015-01-25

In this study an analytical procedure based on microwave-assisted dispersive liquid-liquid microextraction (MA-DLLME) and spectrophotometric coupled with chemometrics methods is proposed to determine uranium. In the proposed method, 4-(2-pyridylazo) resorcinol (PAR) is used as a chelating agent, and chloroform and ethanol are selected as extraction and dispersive solvent. The optimization strategy is carried out by using two level full factorial designs. Results of the two level full factorial design (2(4)) based on an analysis of variance demonstrated that the pH, concentration of PAR, amount of dispersive and extraction solvents are statistically significant. Optimal condition for three variables: pH, concentration of PAR, amount of dispersive and extraction solvents are obtained by using Box-Behnken design. Under the optimum conditions, the calibration graphs are linear in the range of 20.0-350.0 ng mL(-1) with detection limit of 6.7 ng mL(-1) (3δB/slope) and the enrichment factor of this method for uranium reached at 135. The relative standard deviation (R.S.D.) is 1.64% (n=7, c=50 ng mL(-1)). The partial least squares (PLS) modeling was used for multivariate calibration of the spectrophotometric data. The orthogonal signal correction (OSC) was used for preprocessing of data matrices and the prediction results of model, with and without using OSC, were statistically compared. MA-DLLME-OSC-PLS method was presented for the first time in this study. The root mean squares error of prediction (RMSEP) for uranium determination using PLS and OSC-PLS models were 4.63 and 0.98, respectively. This procedure allows the determination of uranium synthesis and real samples such as waste water with good reliability of the determination. Copyright © 2014. Published by Elsevier B.V.

The comparison of the efficiency of traditional lectures to video-supported lectures within the training of the Emergency Medicine residents.

PubMed

Sarıhan, Aydın; Oray, Neşe Colak; Güllüpınar, Birdal; Yanturali, Sedat; Atilla, Ridvan; Musal, Berna

2016-09-01

Recent developments in computer and video technology, multimedia resources enter quickest way possible into medical education and have started to gain popularity. The aim of this study is to evaluate the impact of video-supported lectures on leaning, with comparison to traditional lectures. According to lecture techniques, two separate groups; one is the traditional lectures group (TLG) and the other is video-supported lectures group (VSLG), are formed. While the TLG is offered a traditional lecture the VSLG is offered a video-supported lecture with imbedded videos which are related to the topics in the traditional lecture. Both study groups take pretest and posttest with MCQs (multiple choice questions) and OSCEs (objective structured clinical examination). The study includes 30 volunteer residents in Dokuz Eylul University School of Medicine Department of Emergency Medicine. No difference is observed between TGL and VSLG in pretest and posttest scores (p = 0.949, p = 0.580). And additionally, comparing the scores of both groups, we cannot observe any difference between the pretest OSCE scores of each group (p = 0.300), however posttest OSCE scores shows a dramatic odd in-between (p = 0.010). When pretest MCQs and posttest MCQs mean scores are compared, both tests (TLG, VSLG) has not any significant difference (p=0.949, p = 0.580). Nevertheless, after comparing OSCEs pretest and posttest mean scores, we can see significant difference in mean scores of both (TLG, VSLG), (p = 0.011, p = 0.001). Taken into consideration, the findings of this study shows possibility of improving educational techniques to acquire clinical skills by using local resources and low-cost technology.

Does Changing Examiner Stations During UK Postgraduate Surgery Objective Structured Clinical Examinations Influence Examination Reliability and Candidates' Scores?

PubMed

Brennan, Peter A; Croke, David T; Reed, Malcolm; Smith, Lee; Munro, Euan; Foulkes, John; Arnett, Richard

2016-01-01

Objective structured clinical examinations (OSCE) are widely used for summative assessment in surgery. Despite standardizing these as much as possible, variation, including examiner scoring, can occur which may affect reliability. In study of a high-stakes UK postgraduate surgical OSCE, we investigated whether examiners changing stations once during a long examining day affected marking, reliability, and overall candidates' scores compared with examiners who examined the same scenario all day. An observational study of 18,262 examiner-candidate interactions from the UK Membership of the Royal College of Surgeons examination was carried at 3 Surgical Colleges across the United Kingdom. Scores between examiners were compared using analysis of variance. Examination reliability was assessed with Cronbach's alpha, and the comparative distribution of total candidates' scores for each day was evaluated using t-tests of unit-weighted z scores. A significant difference was found in absolute scores differences awarded in the morning and afternoon sessions between examiners who changed stations at lunchtime and those who did not (p < 0.001). No significant differences were found for the main effects of either broad content area (p = 0.290) or station content area (p = 0.450). The reliability of each day was not affected by examiner switching (p = 0.280). Overall, no difference was found in z-score distribution of total candidate scores and categories of examiner switching. This large study has found that although the range of marks awarded varied when examiners change OSCE stations, examination reliability and the likely candidate outcome were not affected. These results may have implications for examination design and examiner experience in surgical OSCEs and beyond. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Performance of International Medical Students In psychosocial medicine.

PubMed

Huhn, D; Lauter, J; Roesch Ely, D; Koch, E; Möltner, A; Herzog, W; Resch, F; Herpertz, S C; Nikendei, C

2017-07-10

Particularly at the beginning of their studies, international medical students face a number of language-related, social and intercultural challenges. Thus, they perform poorer than their local counterparts in written and oral examinations as well as in Objective Structured Clinical Examinations (OSCEs) in the fields of internal medicine and surgery. It is still unknown how international students perform in an OSCE in the field of psychosocial medicine compared to their local fellow students. All students (N = 1033) taking the OSCE in the field of psychosocial medicine and an accompanying written examination in their eighth or ninth semester between 2012 and 2015 were included in the analysis. The OSCE consisted of four different stations, in which students had to perform and manage a patient encounter with simulated patients suffering from 1) post-traumatic stress disorder, 2) schizophrenia, 3) borderline personality disorder and 4) either suicidal tendency or dementia. Students were evaluated by trained lecturers using global checklists assessing specific professional domains, namely building a relationship with the patient, conversational skills, anamnesis, as well as psychopathological findings and decision-making. International medical students scored significantly poorer than their local peers (p < .001; η 2  = .042). Within the specific professional domains assessed, they showed poorer scores, with differences in conversational skills showing the highest effect (p < .001; η 2  = .053). No differences emerged within the multiple-choice examination (p = .127). International students showed poorer results in clinical-practical exams in the field of psychosocial medicine, with conversational skills yielding the poorest scores. However, regarding factual and practical knowledge examined via a multiple-choice test, no differences emerged between international and local students. These findings have decisive implications for relationship building in

Development of Spiro[cyclopenta[1,2-b:5,4-b']dithiophene-4,9'-fluorene]-Based A-π-D-π-A Small Molecules with Different Acceptor Units for Efficient Organic Solar Cells.

PubMed

Wang, Wengong; Shen, Ping; Dong, Xinning; Weng, Chao; Wang, Guo; Bin, Haijun; Zhang, Jing; Zhang, Zhi-Guo; Li, Yongfang

2017-02-08

Three acceptor-π-donor-π-acceptor (A-π-D-π-A) small molecules (STFYT, STFRDN, and STFRCN) with spiro[cyclopenta[1,2-b:5,4-b']dithiophene-4,9'-fluorene] (STF) as the central donor unit, terthiophene as the π-conjugated bridge, indenedione, 3-ethylrhodanine, or 2-(1,1-dicyanomethylene)rhodanine as the acceptor unit are designed, synthesized, and characterized as electron donor materials in solution-processing organic solar cells (OSCs). The effects of the spiro STF-based central core and different acceptors on the molecular configuration, absorption properties, electronic energy levels, carrier transport properties, the morphology of active layers, and photovoltaic properties are investigated in detail. The three molecules exhibit desirable physicochemical features: wide absorption bands (300-850 nm) and high molar absorption coefficients (4.82 × 10 4 to 7.56 × 10 4 M -1 cm -1 ) and relatively low HOMO levels (-5.15 to -5.38 eV). Density functional theory calculations reveal that the spiro STF central core benefits to reduce the steric hindrance effect between the central donor block and terthiophene bridge and suppress excessive intermolecular aggregations. The optimized OSCs based on these molecules deliver power conversion efficiencies (PCEs) of 6.68%, 3.30%, and 4.33% for STFYT, STFRDN, and STFRCN, respectively. The higher PCE of STFYT-based OSCs should be ascribed to its better absorption ability, higher and balanced hole and electron mobilities, and superior active layer morphology as compared to the other two compounds. So far, this is the first example of developing the A-π-D-π-A type small molecules with a spiro central donor core for high-performance OSC applications. Meanwhile, these results demonstrate that using spiro central block to construct A-π-D-π-A molecule is an alternative and effective strategy for achieving high-performance small molecule donor materials.

Anatomy of ridge discontinuities, transform fault and overlapping spreading centre, at the slow spreading sedimented Andaman Sea Spreading Centre

NASA Astrophysics Data System (ADS)

Jourdain, A.; Singh, S. C.; Klinger, Y.

2013-12-01

Transform faults are the major discontinuities and define the main segment boundaries along spreading centres but their anatomy is poorly understood because of their complex seafloor morphology, even though they are observed at all types of spreading centres. Here, we present high-resolution seismic reflection images across the sedimented Andaman Sea Transform Fault where the sediments record the faulting and allow studying the evolution of the transform fault both in space and time. Furthermore, sediments allow the imaging of the faults down to the Moho depth that provides insight on the interplay between tectonic and magmatic processes. On the other hand, overlapping spreading centres (OSC) are small-scale discontinuities, possibly transient, and are observed only along fast or intermediate spreading centres. Exceptionally, an overlapping spreading centre is present at the slow spreading Andaman Sea Spreading Centre, which, we suggest, is due to the presence of thick sediments that hamper the efficient hydrothermal circulation allowing magma to stay much longer in the crust at different depths, and up to close to the segment ends, leading to the development of an overlapping spreading. The seismic reflection images across the OSC indicate the presence of large magma bodies in the crust. Seismic images also provide images of active faults allowing to study the link between faulting and magmatism. Interestingly, an earthquake swarm occurred at propagating limb of the OSC in 2006, after the great 2004 Andaman-Sumatra earthquake of Mw=9.3, highlighting the migration of the OSC westward. In this paper, we will show seismic reflection images and interpret these images in the light of bathymetry and earthquake data, and provide the anatomy of the ridge discontinuities along the slow spreading sedimented Andaman Sea Spreading Centre.

Comparison of physical examination performance of medical students trained by musculoskeletal versus non-musculoskeletal specialists.

PubMed

Melo, Luciano; Schrieber, Leslie; Eyles, Jillian; Deveza, Leticia A; Meneses, Sarah R F; Hunter, David J

2017-04-01

To compare the musculoskeletal (MSK) physical examination skills, knowledge acquisition and performance of first-year medical students trained by MSK specialist tutors to students trained by non-MSK specialist tutors, after a 6-week MSK physical examination tutorial program. Twenty-first year medical students took part in the study. They were recruited into two groups, according to their exposure to either an MSK specialist or a non-MSK specialist tutor during their 6-week MSK training block. Knowledge acquisition was measured via a pre- and post-training objective structured clinical examination (OSCE). We assessed students' self-belief and confidence levels regarding their newly acquired skills via a questionnaire. Independent t tests were used to examine mean group differences of OSCE scores and perceived level of confidence. Both groups demonstrated a significant improvement (3.9 and 3.8 points, respectively, on an eight-point scale for shoulder assessment, P < 0.01, 3.3 and 3.5, respectively, on a five-point scale for spine assessment, P < 0.01) in OSCE scores compared to baseline after completing the 6-week MSK physical examination tutorial program. There was no between-group difference in the OSCE scores from pre- to post-training (P = 0.92 for shoulder, P = 0.66 for spine) or for perceived level of confidence in performing a basic MSK examination after training (P = 0.91). Students exposed to MSK specialist tutors did not demonstrate increased skill levels or knowledge in the area of MSK physical examination compared to those receiving the same training under the supervision of non-MSK specialist tutors. Both student groups demonstrated improvement. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

A Global Assessment of Rain-Dissolved Organic Carbon

NASA Astrophysics Data System (ADS)

Safieddine, S.; Heald, C. L.

2017-12-01

Precipitation is the largest physical removal pathway of atmospheric organic carbon from the atmosphere. The removed carbon is transferred to the land and ocean in the form of dissolved organic carbon (DOC). Limited measurements have hindered efforts to characterize global DOC. In this poster presentation, we show the first simulated global DOC distribution based on a GEOS-Chem model simulation of the atmospheric reactive carbon budget. Over the ocean, simulated DOC concentrations are between 0.1 to 1 mgCL-1 with a total of 85 TgCyr-1 deposited. DOC concentrations are higher inland, ranging between 1 and 10 mgCL-1, producing a total of 188 TgCyr-1 terrestrial organic wet deposition. We compare the 2010 simulated DOC to a 30-year synthesis of available DOC measurements over different environments. Despite imperfect matching of observational and simulated time intervals, the model is able to reproduce much of the spatial variability of DOC (r= 0.63), with a low bias of 35%. We compare the global average carbon oxidation state (OSc) of both atmospheric and dissolved organic carbon, as a simple metric for describing the chemical composition of organics. In the global atmosphere reactive organic carbon (ROC) is dominated by hydrocarbons and ketones, and OSc, ranges from -1.8 to -0.6. In the dissolved form, formaldehyde, formic acid, primary and secondary semi-volatiles organic aerosol dominate the DOC concentrations. The increase in solubility upon oxidation leads to a global increase in OSc in rainwater with -0.6<=OSc <=0. This simulation provides new insight into the current model representation of the flow of atmospheric and rain-dissolved organic carbon, and new opportunities to use observations and simulations to understand the DOC reaching land and ocean.

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

DOE PAGES

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.; ...

2015-10-19

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present paper, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute ofmore » Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. Finally, this could be particularly important in agricultural areas where there are significant sources of OSCs.« less

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions.

PubMed

Perraud, Véronique; Horne, Jeremy R; Martinez, Andrew S; Kalinowski, Jaroslaw; Meinardi, Simone; Dawson, Matthew L; Wingen, Lisa M; Dabdub, Donald; Blake, Donald R; Gerber, R Benny; Finlayson-Pitts, Barbara J

2015-11-03

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present work, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine-California Institute of Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. This could be particularly important in agricultural areas where there are significant sources of OSCs.

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

PubMed Central

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.; Kalinowski, Jaroslaw; Meinardi, Simone; Dawson, Matthew L.; Wingen, Lisa M.; Dabdub, Donald; Blake, Donald R.; Gerber, R. Benny; Finlayson-Pitts, Barbara J.

2015-01-01

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present work, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute of Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. This could be particularly important in agricultural areas where there are significant sources of OSCs. PMID:26483454

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present paper, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute ofmore » Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. Finally, this could be particularly important in agricultural areas where there are significant sources of OSCs.« less

Effect of TiO2 modification with amino-based self-assembled monolayer on inverted organic solar cell

NASA Astrophysics Data System (ADS)

Tozlu, Cem; Mutlu, Adem; Can, Mustafa; Havare, Ali Kemal; Demic, Serafettin; Icli, Sıddık

2017-11-01

The effects of surface modification of titanium dioxide (TiO2) on the performance of inverted type organic solar cells (i-OSCs) was investigated in this study. A series of benzoic acid derivatized self-assembled monolayer (SAM) molecules of 4‧-[(hexyloxy)phenyl]amino-3,5-biphenyl dicarboxylic acid (CT17) and 4‧-[1-naphthyl (phenyl)amino]biphenyl-4-carboxylic acid (CT19) were utilized to modify the interface between TiO2 buffer layer and poly-3 hexylthiophene (P3HT):[6,6]-phenyl C61 butyric acid methyl ester (PC61BM) active layer having the device structure of ITO/TiO2/SAM/P3HT:PC61BM/MoO3/Ag. The work function and surface wetting properties of TiO2 buffer layer served as electron transporting layer between ITO and PC61BM active layer were tuned by SAM method. The solar cell of the SAM modified devices exhibited better performance. The power conversion efficiency (PCE) of i-OSCs devices with bare TiO2 electrodes enhanced from 2.00% to 2.21% and 2.43% with CT17 and CT19 treated TiO2 electrodes, respectively. The open circuit voltage (Voc) of the SAM treated TiO2 devices reached to 0.60 V and 0.61 V, respectively, while the Voc of untreated TiO2 was 0.57 V. The water contact angle of i-OSCs with CT17 and CT19 SAMs was also higher than the value of the unmodified TiO2 electrode. These results show that inserting a monolayer at the interface between organic and inorganic layers is an useful alternative method to improve the performance of i-OSCs.

A novel reductive amination method with isotopic formaldehydes for the preparation of internal standard and standards for determining organosulfur compounds in garlic.

PubMed

Tsai, De-Cheng; Liu, Meng-Chieh; Lin, Yi-Reng; Huang, Mei-Fang; Liang, Shih-Shin

2016-04-15

Garlic (Allium sativum) is a long-cultivated plant that is widely utilized in cooking and has been employed as a medicine for over 4000 years. In this study, we fabricated standards and internal standards (ISs) for absolute quantification via reductive amination with isotopic formaldehydes. Garlic has four abundant organosulfur compounds (OSCs): S-allylcysteine, S-allylcysteinine sulfoxide, S-methylcysteine, and S-ethylcysteine are abundant in garlic. OSCs with primary amine groups were reacted with isotopic formaldehydes to synthesize ISs and standards. Cooked and uncooked garlic samples were compared, and we utilized tandem mass spectrometry equipped with a selective reaction monitoring technique to absolutely quantify the four organosulfur compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

KSC-03pd0163

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- Workers in the Multi-Purpose Processing Facility check the fairing placed around the Solar Radiation and Climate Experiment (SORCE) satellite. When fully encapsulated, the satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0157

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - Workers in the Multi-Purpose Processing Facility check the outside of the fairing around the Solar Radiation and Climate Experiment (SORCE) satellite. When completely encapsulated, the satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0158

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- Workers in the Multi-Purpose Processing Facility move part of the fairing toward the Solar Radiation and Climate Experiment (SORCE) satellite for encapsulation. The satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

Origin of Non-Radiative Voltage Losses in Fullerene-Based Organic Solar Cells

NASA Astrophysics Data System (ADS)

Benduhn, Johannes; Tvingstedt, Kristofer; Piersimoni, Fortunato; Ullbrich, Sascha; Neher, Dieter; Spoltore, Donato; Vandewal, Koen

The open-circuit voltage of organic solar cells (OSCs) is low as compared to the optical gap of the absorber molecules, indicating high energy losses per absorbed photon. These voltage losses arise only partly due to necessity of an electron transfer event to dissociate the excitons. A large part of these voltage losses is due to recombination of photo-generated charge carriers, including inevitable radiative recombination. In this work, we study the non-radiative recombination losses and we find that they increase when the energy difference between charge transfer (CT) state and ground state decreases. This behavior is in agreement with the \\x9Denergy gap law for non-radiative transition\\x9D, which implies that internal conversion from CT state to ground state is facilitated by skeletal molecular vibrations. This intrinsic loss mechanism, which until now has not been thoroughly considered for OSCs, is different in its nature as compared to the commonly considered inorganic photovoltaic loss mechanisms of defect, surface, and Auger recombination. As a consequence, the theoretical upper limit for the power conversion efficiency of a single junction OSC reduces by 25% as compared to the Shockley-Queisser limit for an optimal optical gap of the main absorber between (1.45-1.65) eV.

Plasmonically sensitized metal-oxide electron extraction layers for organic solar cells.

PubMed

Trost, S; Becker, T; Zilberberg, K; Behrendt, A; Polywka, A; Heiderhoff, R; Görrn, P; Riedl, T

2015-01-16

ZnO and TiOx are commonly used as electron extraction layers (EELs) in organic solar cells (OSCs). A general phenomenon of OSCs incorporating these metal-oxides is the requirement to illuminate the devices with UV light in order to improve device characteristics. This may cause severe problems if UV to VIS down-conversion is applied or if the UV spectral range (λ < 400 nm) is blocked to achieve an improved device lifetime. In this work, silver nanoparticles (AgNP) are used to plasmonically sensitize metal-oxide based EELs in the vicinity (1-20 nm) of the metal-oxide/organic interface. We evidence that plasmonically sensitized metal-oxide layers facilitate electron extraction and afford well-behaved highly efficient OSCs, even without the typical requirement of UV exposure. It is shown that in the plasmonically sensitized metal-oxides the illumination with visible light lowers the WF due to desorption of previously ionosorbed oxygen, in analogy to the process found in neat metal oxides upon UV exposure, only. As underlying mechanism the transfer of hot holes from the metal to the oxide upon illumination with hν < Eg is verified. The general applicability of this concept to most common metal-oxides (e.g. TiOx and ZnO) in combination with different photoactive organic materials is demonstrated.

Challenges associated with the sampling and analysis of organosulfur compounds in air using real-time PTR-ToF-MS and off-line GC-FID

NASA Astrophysics Data System (ADS)

Perraud, V.; Meinardi, S.; Blake, D. R.; Finlayson-Pitts, B. J.

2015-12-01

Organosulfur compounds (OSC) are naturally emitted via various processes involving phytoplankton and algae in marine regions, from animal metabolism and from biomass decomposition inland. These compounds are malodorant and reactive. Their oxidation to methanesulfonic and sulfuric acids leads to the formation and growth of atmospheric particles, which are known to have negative effects on visibility, climate and human health. In order to predict particle formation events, accurate measurements of the OSC precursors are essential. Here, two different approaches, proton-transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) and canister sampling coupled with GC-FID are compared for both laboratory standards [dimethyl sulfide (DMS), dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and methanethiol (MTO)] and for a complex sample. Results show that both techniques produce accurate quantification of DMS. While PTR-ToF-MS provides real-time measurements of all four OSCs individually, significant fragmentation of DMDS and DMTS occurs, which can complicate their identification in complex mixtures. Canister sampling coupled with GC-FID provides excellent sensitivity for DMS, DMDS and DMTS. However, MTO was observed to react on metal surfaces to produce DMDS and, in the presence of hydrogen sulfide, even DMTS. Avoiding metal in sampling systems seems to be necessary for measuring all but dimethyl sulfide in air.

New Geochemical Analyses Reveal Crustal Accretionary Processes at The Overlapping Spreading Center Near 3 N East Pacific Rise

NASA Astrophysics Data System (ADS)

Smithka, I. N.; Perfit, M. R.

2013-12-01

Mid-ocean ridges (MORs) are the sites of oceanic lithosphere creation and construction. Ridge discontinuities are a global phenomenom but are not as well understood as ridge axes. Geochemical analyses provide insights into upper mantle processes since elements fractionate with melting and freezing as well as reside in material to retain source signature. Lavas collected from ridge discontinuities consist of greater chemical diversity and represent variations in source, melting parameters, and local crustal processes. The small overlapping spreading center (OSC) near the third parallel north on the East Pacific Rise has been superficially analyzed previously, but here we present new isotope analyses and expand our understanding of MOR processes and processes near OSCs. Initial analyses of lavas collected in 2000 on AHA-NEMO2 revealed normal MOR basalt trends in rare earth element enrichments as well as in major element concentrations. Crystal fractionation varies along the tips of both axes, with MgO and TiO2 concentrations increasing towards the OSC basin. Newly analyzed Sr, Nd, and Pb isotope ratios will further constrain the nature of geochemical diversity along axis. As the northern tip seems to be propagating and the southern tip dying, lavas collected from each may reflect two different underlying mantle melting and magma storage processes.

Peer feedback as an aid to learning--what do we want? Feedback. When do we want it? Now!

PubMed

Cushing, Annie; Abbott, Stephen; Lothian, Doug; Hall, Angela; Westwood, Olwyn M R

2011-01-01

With 360° appraisals integral to professional life, learning how to give constructive feedback is an essential generic skill. To use a formative objective structured clinical examination (OSCE) for skills acquisition and development in giving feedback, whilst facilitating awareness of the importance of communication skills in clinical practice. Medical and nursing students took part in a formative OSCE. Using actors as simulated patients, a three-station OSCE circuit was repeated three times so that students could rotate through the roles as 'candidate', 'examiner' and 'observer'. As 'candidates', they received immediate feedback on their consultation from the 'examiner'/'observer'. The events were evaluated using a questionnaire and focus groups. Students immensely valued this learning event for considering expectations for a performance (91-100%). Concerns around giving peers feedback were acknowledged, and they were divided on preference for feedback from peers or tutors (48% versus 52%). But training in providing feedback and criteria for assessment were considered helpful, as was instruction by faculty to give corrective feedback to peers. Peer observation and professional accountability for giving constructive feedback enhanced awareness of their skills education and training needs. It also opened the dialogue for identifying opportunities for peer assessment and feedback to support work-based education and skills development.

Self-oscillation of standing spin wave in ring resonator with proportional-integral-derivative control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, B.; Urazuka, Y.; Chen, H.

2014-05-07

We report on numerical analysis on self-oscillation of standing spin wave excited in a nanostructured active ring resonator, consists of a ferromagnetic nanowire with perpendicular anisotropy. The confined resonant modes are along the nanowire length. A positive feedback with proportional-integral-derivative gain control was adopted in the active ring. Stable excitation of the 1st order standing spin wave has been demonstrated with micromagnetic simulations, taking into account the thermal effect with a random field model. The stationary standing spin wave with a pre-determined set variable of precession amplitude was attained within 20 ns by optimizing the proportional-integral-derivative gain control parameters. The resultmore » indicates that a monochromatic oscillation frequency f{sub osc} is extracted from the initial thermal fluctuation state and selectively amplified with the positive feedback loop. The obtained f{sub osc} value of 5.22 GHz practically agrees with the theoretical prediction from dispersion relation of the magneto static forward volume wave. It was also confirmed that the f{sub osc} change due to the temperature rise can be compensated with an external perpendicular bias field H{sub b}. The observed quick compensation time with an order of nano second suggests the fast operation speed in the practical device application.« less

Test anxiety and academic performance in chiropractic students.

PubMed

Zhang, Niu; Henderson, Charles N R

2014-01-01

Objective : We assessed the level of students' test anxiety, and the relationship between test anxiety and academic performance. Methods : We recruited 166 third-quarter students. The Test Anxiety Inventory (TAI) was administered to all participants. Total scores from written examinations and objective structured clinical examinations (OSCEs) were used as response variables. Results : Multiple regression analysis shows that there was a modest, but statistically significant negative correlation between TAI scores and written exam scores, but not OSCE scores. Worry and emotionality were the best predictive models for written exam scores. Mean total anxiety and emotionality scores for females were significantly higher than those for males, but not worry scores. Conclusion : Moderate-to-high test anxiety was observed in 85% of the chiropractic students examined. However, total test anxiety, as measured by the TAI score, was a very weak predictive model for written exam performance. Multiple regression analysis demonstrated that replacing total anxiety (TAI) with worry and emotionality (TAI subscales) produces a much more effective predictive model of written exam performance. Sex, age, highest current academic degree, and ethnicity contributed little additional predictive power in either regression model. Moreover, TAI scores were not found to be statistically significant predictors of physical exam skill performance, as measured by OSCEs.

All-Solution-Processed Metal-Oxide-Free Flexible Organic Solar Cells with Over 10% Efficiency.

PubMed

Song, Wei; Fan, Xi; Xu, Bingang; Yan, Feng; Cui, Huiqin; Wei, Qiang; Peng, Ruixiang; Hong, Ling; Huang, Jiaming; Ge, Ziyi

2018-05-16

All-solution-processing at low temperatures is important and desirable for making printed photovoltaic devices and also offers the possibility of a safe and cost-effective fabrication environment for the devices. Herein, an all-solution-processed flexible organic solar cell (OSC) using poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) electrodes is reported. The all-solution-processed flexible devices yield the highest power conversion efficiency of 10.12% with high fill factor of over 70%, which is the highest value for metal-oxide-free flexible OSCs reported so far. The enhanced performance is attributed to the newly developed gentle acid treatment at room temperature that enables a high-performance PEDOT:PSS/plastic underlying substrate with a matched work function (≈4.91 eV), and the interface engineering that endows the devices with better interface contacts and improved hole mobility. Furthermore, the flexible devices exhibit an excellent mechanical flexibility, as indicated by a high retention (≈94%) of the initial efficiency after 1000 bending cycles. This work provides a simple route to fabricate high-performance all-solution-processed flexible OSCs, which is important for the development of printing, blading, and roll-to-roll technologies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Web-based objective structured clinical examination with remote standardized patients and Skype: resident experience.

PubMed

Langenau, Erik; Kachur, Elizabeth; Horber, Dot

2014-07-01

Using Skype and remote standardized patients (RSPs), investigators sought to evaluate user acceptance of a web-based objective structured clinical examination (OSCE) among resident physicians. After participating in four web-based clinical encounters addressing pain with RSPs, 59 residents from different training programs, disciplines and geographic locations completed a 52-item questionnaire regarding their experience with Skype and RSPs. Open-ended responses were solicited as well. The majority of participants (97%) agreed or strongly agreed the web-based format was convenient and a practical learning exercise, and 90% agreed or strongly agreed the format was effective in teaching communication skills. Although 93% agreed or strongly agreed they could communicate easily with RSPs using Skype, 80% preferred traditional face-to-face clinical encounters, and 58% reported technical difficulties during the encounters. Open-ended written responses supported survey results. Findings from this study expose challenges with technology and human factors, but positive experiences support the continued investigation of web-based OSCEs as a synchronous e-learning initiative for teaching and assessing doctor-patient communication. Such educational programs are valuable but unlikely to replace face-to-face encounters with patients. This web-based OSCE program provides physician learners with additional opportunity to improve doctor-patient communication. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Does self-efficacy mediate the association between socioeconomic background and emotional symptoms among schoolchildren?

PubMed

Meilstrup, Charlotte; Thygesen, Lau Caspar; Nielsen, Line; Koushede, Vibeke; Cross, Donna; Holstein, Bjørn Evald

2016-05-01

Emotional symptoms are widespread among adolescents with the highest prevalence among lower socioeconomic groups. Less is known about why and how to reduce this inequality but personal control, e.g., self-efficacy may be crucial. This study examines whether self-efficacy is a mediator in the association between occupational social class (OSC) and emotional symptoms. Data stem from the cross-sectional Health Behavior in School-aged Children-Methodology Development Survey 2012 (HBSC-MDS) conducted among 11-15-year old schoolchildren in two Danish municipalities. Participation rate was 76.8 % of 5165 enrolled schoolchildren, n = 3969. Low OSC is associated with higher odds of daily emotional symptoms and low selfefficacy. Schoolchildren with low self-efficacy have higher odds for daily emotional symptoms. We find a strong and statistically significant direct effect between low OSC and daily emotional symptoms (OR = 1.55, 95 % CI: 1.33; 1.84) and a borderline statistically significant indirect effect of self-efficacy [OR = 1.17 (0.99; 1.38)]. Socioeconomic inequality in emotional symptoms exists. This inequality is partly explained by socioeconomic inequality in self-efficacy. Promotion of personal competences like self-efficacy may reduce emotional symptoms among all socioeconomic groups, thereby reducing socioeconomic inequalities in emotional symptoms.

Noninvasive Recognition and Biomarkers of Early Allergic Asthma in Cats Using Multivariate Statistical Analysis of NMR Spectra of Exhaled Breath Condensate

PubMed Central

Fulcher, Yan G.; Fotso, Martial; Chang, Chee-Hoon; Rindt, Hans; Reinero, Carol R.

2016-01-01

Asthma is prevalent in children and cats, and needs means of noninvasive diagnosis. We sought to distinguish noninvasively the differences in 53 cats before and soon after induction of allergic asthma, using NMR spectra of exhaled breath condensate (EBC). Statistical pattern recognition was improved considerably by preprocessing the spectra with probabilistic quotient normalization and glog transformation. Classification of the 106 preprocessed spectra by principal component analysis and partial least squares with discriminant analysis (PLS-DA) appears to be impaired by variances unrelated to eosinophilic asthma. By filtering out confounding variances, orthogonal signal correction (OSC) PLS-DA greatly improved the separation of the healthy and early asthmatic states, attaining 94% specificity and 94% sensitivity in predictions. OSC enhancement of multi-level PLS-DA boosted the specificity of the prediction to 100%. OSC-PLS-DA of the normalized spectra suggest the most promising biomarkers of allergic asthma in cats to include increased acetone, metabolite(s) with overlapped NMR peaks near 5.8 ppm, and a hydroxyphenyl-containing metabolite, as well as decreased phthalate. Acetone is elevated in the EBC of 74% of the cats with early asthma. The noninvasive detection of early experimental asthma, biomarkers in EBC, and metabolic perturbation invite further investigation of the diagnostic potential in humans. PMID:27764146

Melt-processing of small molecule organic photovoltaics via bulk heterojunction compatibilization.

PubMed

Rahmanudin, Aiman; Yao, Liang; Jeanbourquin, Xavier A; Liu, Yongpeng; Sekar, Arvindh; Ripaud, Emilie; Sivula, Kevin

2018-05-21

Melt-processing of organic semiconductors (OSCs) is a promising environmentally-friendly technique that can alleviate dependence on toxic chlorinated solvents. While melt-processed single-component OSC devices ( e.g. field-effect-transistors) have been demonstrated, multi-component bulk heterojunctions (BHJs) for organic photovoltaics (OPVs) remain a challenge. Herein, we demonstrate a strategy that affords tunable BHJ phase segregation and domain sizes from a single-phase homogeneous melt by employing strongly-crystalline small-molecule OSCs together with a customized molecular compatibilizing (MCP) additive. An optimized photoactive BHJ with 50 wt% MCP achieved a device power conversion efficiency of ca. 1% after melting the active layer at 240 °C (15 min, followed by slow cooling) before deposition of the top electrode. BHJ morphology characterization using atomic force and Kelvin probe microscopy, X-ray diffraction, and photo-luminescence measurements further demonstrate the trade-off between free charge generation and transport with respect to MCP loading in the BHJ. In addition, a functional OPV was also obtained from the melt-processing of dispersed micron-sized solid BHJ particles into a smooth and homogeneous thin-film by using the MCP approach. These results demonstrate that molecular compatibilization is a key prerequisite for further developments towards true solvent-free melt-processed BHJ OPV systems.

The Influence of Fluorination on Nano-Scale Phase Separation and Photovoltaic Performance of Small Molecular/PC71BM Blends

PubMed Central

Lu, Zhen; Liu, Wen; Li, Jingjing; Fang, Tao; Li, Wanning; Zhang, Jicheng; Feng, Feng; Li, Wenhua

2016-01-01

To investigate the fluorination influence on the photovoltaic performance of small molecular based organic solar cells (OSCs), six small molecules based on 2,1,3-benzothiadiazole (BT), and diketopyrrolopyrrole (DPP) as core and fluorinated phenyl (DFP) and triphenyl amine (TPA) as different terminal units (DFP-BT-DFP, DFP-BT-TPA, TPA-BT-TPA, DFP-DPP-DFP, DFP-DPP-TPA, and TPA-DPP-TPA) were synthesized. With one or two fluorinated phenyl as the end group(s), HOMO level of BT and DPP based small molecular donors were gradually decreased, inducing high open circuit voltage for fluorinated phenyl based OSCs. DFP-BT-TPA and DFP-DPP-TPA based blend films both displayed stronger nano-scale aggregation in comparison to TPA-BT-TPA and TPA-DPP-TPA, respectively, which would also lead to higher hole motilities in devices. Ultimately, improved power conversion efficiency (PCE) of 2.17% and 1.22% was acquired for DFP-BT-TPA and DFP-DPP-TPA based devices, respectively. These results demonstrated that the nano-scale aggregation size of small molecules in photovoltaic devices could be significantly enhanced by introducing a fluorine atom at the donor unit of small molecules, which will provide understanding about the relationship of chemical structure and nano-scale phase separation in OSCs. PMID:28335208

Strategies for Improving the Performance of Sensors Based on Organic Field-Effect Transistors.

PubMed

Wu, Xiaohan; Mao, Shun; Chen, Junhong; Huang, Jia

2018-04-01

Organic semiconductors (OSCs) have been extensively studied as sensing channel materials in field-effect transistors due to their unique charge transport properties. Stimulation caused by its environmental conditions can readily change the charge-carrier density and mobility of OSCs. Organic field-effect transistors (OFETs) can act as both signal transducers and signal amplifiers, which greatly simplifies the device structure. Over the past decades, various sensors based on OFETs have been developed, including physical sensors, chemical sensors, biosensors, and integrated sensor arrays with advanced functionalities. However, the performance of OFET-based sensors still needs to be improved to meet the requirements from various practical applications, such as high sensitivity, high selectivity, and rapid response speed. Tailoring molecular structures and micro/nanofilm structures of OSCs is a vital strategy for achieving better sensing performance. Modification of the dielectric layer and the semiconductor/dielectric interface is another approach for improving the sensor performance. Moreover, advanced sensory functionalities have been achieved by developing integrated device arrays. Here, a brief review of strategies used for improving the performance of OFET sensors is presented, which is expected to inspire and provide guidance for the design of future OFET sensors for various specific and practical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of basic clinical skills training on objective structured clinical examination performance.

PubMed

Jünger, Jana; Schäfer, Sybille; Roth, Christiane; Schellberg, Dieter; Friedman Ben-David, Miriam; Nikendei, Christoph

2005-10-01

The aim of curriculum reform in medical education is to improve students' clinical and communication skills. However, there are contradicting results regarding the effectiveness of such reforms. A study of internal medicine students was carried out using a static group design. The experimental group consisted of 77 students participating in 7 sessions of communication training, 7 sessions of skills-laboratory training and 7 sessions of bedside-teaching, each lasting 1.5 hours. The control group of 66 students from the traditional curriculum participated in equally as many sessions but was offered only bedside teaching. Students' cognitive and practical skills performance was assessed using Multiple Choice Question (MCQ) testing and an objective structured clinical examination (OSCE), delivered by examiners blind to group membership. The experimental group performed significantly better on the OSCE than did the control group (P < 0.01), whereas the groups did not differ on the MCQ test (P < 0.15). This indicates that specific training in communication and basic clinical skills enabled students to perform better in an OSCE, whereas its effects on knowledge did not differ from those of the traditional curriculum. Curriculum reform promoting communication and basic clinical skills are effective and lead to an improved performance in history taking and physical examination skills.

Effects of thermal maturation and thermochemical sulfate reduction on compound-specific sulfur isotopic compositions of organosulfur compounds in Phosphoria oils from the Bighorn Basin, USA

USGS Publications Warehouse

Ellis, Geoffrey S.; Said-Ahamed, Ward; Lillis, Paul G.; Shawar, Lubna; Amrani, Alon

2017-01-01

Compound-specific sulfur isotope analysis was applied to a suite of 18 crude oils generated from the Permian Phosphoria Formation in the Bighorn Basin, western USA. These oils were generated at various levels of thermal maturity and some experienced thermochemical sulfate reduction (TSR). This is the first study to examine the effects of thermal maturation on stable sulfur isotopic compositions of individual organosulfur compounds (OSCs) in crude oil. A general trend of 34S enrichment in all of the studied compounds with increasing thermal maturity was observed, with the δ34S values of alkyl-benzothiophenes (BTs) tending to be enriched in 34S relative to those of the alkyl-dibenzothiophenes (DBTs) in lower-maturity oils. As thermal maturity increases, δ34S values of both BTs and DBTs become progressively heavier, but the difference in the average δ34S value of the BTs and DBTs (Δ34S BT-DBT) decreases. Differences in the isotopic response to thermal stress exhibited by these two compound classes are considered to be the result of relative differences in their thermal stabilities. TSR-altered Bighorn Basin oils have OSCs that are generally enriched in 34S relative to non-TSR-altered oils, with the BTs being enriched in 34S relative to the DBTs, similar to the findings of previous studies. However, several oils that were previously interpreted to have been exposed to minor TSR have Δ34S BT-DBT values that do not support this interpretation. The δ34S values of the BTs and DBTs in some of these oils suggest that they did not experience TSR, but were derived from a more thermally mature source. The heaviest δ34S values observed in the OSCs are enriched in 34S by up to 10‰ relative to that of Permian anhydrite in the Bighorn Basin, suggesting that there may be an alternate or additional source of sulfate in some parts of the basin. These results indicate that the sulfur isotopic composition of OSCs in oil provides a sensitive indicator for the extent of TSR

32 CFR 145.4 - Policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... L. 95-454 and of the responsibilities of the Department of Defense. (f) OSC investigative requests involving classified information shall be accorded special attention and prompt consideration under existing...

Immunoregulation of follicular renewal, selection, POF, and menopause in vivo, vs. neo-oogenesis in vitro, POF and ovarian infertility treatment, and a clinical trial

PubMed Central

2012-01-01

The immune system plays an important role in the regulation of tissue homeostasis ("tissue immune physiology"). Function of distinct tissues during adulthood, including the ovary, requires (1) Renewal from stem cells, (2) Preservation of tissue-specific cells in a proper differentiated state, which differs among distinct tissues, and (3) Regulation of tissue quantity. Such morphostasis can be executed by the tissue control system, consisting of immune system-related components, vascular pericytes, and autonomic innervation. Morphostasis is established epigenetically, during morphogenetic (developmental) immune adaptation, i.e., during the critical developmental period. Subsequently, the tissues are maintained in a state of differentiation reached during the adaptation by a “stop effect” of resident and self renewing monocyte-derived cells. The later normal tissue is programmed to emerge (e.g., late emergence of ovarian granulosa cells), the earlier its function ceases. Alteration of certain tissue differentiation during the critical developmental period causes persistent alteration of that tissue function, including premature ovarian failure (POF) and primary amenorrhea. In fetal and adult human ovaries the ovarian surface epithelium cells called ovarian stem cells (OSC) are bipotent stem cells for the formation of ovarian germ and granulosa cells. Recently termed oogonial stem cells are, in reality, not stem but already germ cells which have the ability to divide. Immune system-related cells and molecules accompany asymmetric division of OSC resulting in the emergence of secondary germ cells, symmetric division, and migration of secondary germ cells, formation of new granulosa cells and fetal and adult primordial follicles (follicular renewal), and selection and growth of primary/preantral, and dominant follicles. The number of selected follicles during each ovarian cycle is determined by autonomic innervation. Morphostasis is altered with advancing age, due

OrbView-3 Initial On-Orbit Characterization

NASA Technical Reports Server (NTRS)

Ross, Kent; Blonski, Slawomir; Holekamp, Kara; Pagnutti, Mary; Zanoni, Vicki; Carver, David; Fendley, Debbie; Smith, Charles

2004-01-01

NASA at Stennis Space Center (SSC) established a Space Act Agreement with Orbital Sciences Corporation (OSC) and ORBIMAGE Inc. to collaborate on the characterization of the OrbView-3 system and its imagery products and to develop characterization techniques further. In accordance with the agreement, NASA performed an independent radiometric, spatial, and geopositional accuracy assessment of OrbView-3 imagery acquired before completion of the system's initial on-orbit checkout. OSC acquired OrbView-3 imagery over SSC from July 2003 through January 2004, and NASA collected ground reference information coincident with many of these acquisitions. After evaluating all acquisitions, NASA deemed two multispectral images and five panchromatic images useful for characterization. NASA then performed radiometric, spatial, and geopositional characterizations.

One-step synthesis of carbon nanosheets converted from a polycyclic compound and their direct use as transparent electrodes of ITO-free organic solar cells.

PubMed

Son, Su-Young; Noh, Yong-Jin; Bok, Changsuk; Lee, Sungho; Kim, Byoung Gak; Na, Seok-In; Joh, Han-Ik

2014-01-21

Through a catalyst- and transfer-free process, we fabricated indium tin oxide (ITO)-free organic solar cells (OSCs) using a carbon nanosheet (CNS) with properties similar to graphene. The morphological and electrical properties of the CNS derived from a polymer of intrinsic microporosity-1 (PIM-1), which is mainly composed of several aromatic hydrocarbons and cycloalkanes, can be easily controlled by adjusting the polymer concentration. The CNSs, which are prepared by simple spin-coating and heat-treatment on a quartz substrate, are directly used as the electrodes of ITO-free OSCs, showing a high efficiency of approximately 1.922% under 100 mW cm(-2) illumination and air mass 1.5 G conditions. This catalyst- and transfer-free approach is highly desirable for electrodes in organic electronics.

Influence of transition metal electronegativity on the oxygen storage capacity of perovskite oxides.

PubMed

Liu, Lu; Taylor, Daniel D; Rodriguez, Efrain E; Zachariah, Michael R

2016-08-16

The selection of highly efficient oxygen carriers (OCs) is a key step necessary for the practical development of chemical looping combustion (CLC). In this study, a series of ABO3 perovskites, where A = La, Ba, Sr, Ca and B = Cr, Mn, Fe, Co, Ni, Cu, are synthesized and tested in a fixed bed reactor for reactivity and stability as OCs with CH4 as the fuel. We find that the electronegativity of the transition metal on the B-site (λB), is a convenient descriptor for oxygen storage capacity (OSC) of our perovskite samples. By plotting OSC for total methane oxidation against λB, we observe an inverted volcano plot relationship. These results could provide useful guidelines for perovskite OC design and their other energy related applications.

Advanced Measurement Devices for the Microgravity Electromagnetic Levitation Facility EML

NASA Technical Reports Server (NTRS)

Brillo, Jurgen; Fritze, Holger; Lohofer, Georg; Schulz, Michal; Stenzel, Christian

2012-01-01

This paper reports on two advanced measurement devices for the microgravity electromagnetic levitation facility (EML), which is currently under construction for the use onboard the "International Space Station (ISS)": the "Sample Coupling Electronics (SCE)" and the "Oxygen Sensing and Control Unit (OSC)". The SCE measures by a contactless, inductive method the electrical resistivity and the diameter of a spherical levitated metallic droplet by evaluating the voltage and electrical current applied to the levitation coil. The necessity of the OSC comes from the insight that properties like surface tension or, eventually, viscosity cannot seriously be determined by the oscillating drop method in the EML facility without knowing the conditions of the surrounding atmosphere. In the following both measurement devices are explained and laboratory test results are presented.

KSC-03pd0154

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. -- Workers in the Multi-Purpose Processing Facility look over the Solar Radiation and Climate Experiment (SORCE) satellite after the first half of the fairing is put in place. When completely encapsulated, the satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0152

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - A worker in the Multi-Purpose Processing Facility looks over the Solar Radiation and Climate Experiment (SORCE) satellite as the first half of the fairing is put in place. When completely encapsulated, the satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

KSC-03pd0153

NASA Image and Video Library

2003-01-16

KENNEDY SPACE CENTER, FLA. - Workers in the Multi-Purpose Processing Facility look over the Solar Radiation and Climate Experiment (SORCE) satellite as the first half of the fairing is put in place. When completely encapsulated, the satellite will be installed in the Pegasus XL launch vehicle. Built by Orbital Sciences Corporation (OSC), SORCE will study and measure solar irradiance as a source of energy in the Earth's atmosphere. The launch of SORCE is scheduled for Jan. 25 at 3:14 p.m. from Cape Canaveral Air Force Station, Fla. The drop of the Pegasus will be from OSC's L-1011 aircraft at an altitude of 39,000 feet over the Atlantic Ocean approximately 100 miles east-southeast of Cape Canaveral.

C-terminal Amidation of an Osteocalcin-derived Peptide Promotes Hydroxyapatite Crystallization*

PubMed Central

Hosseini, Samaneh; Naderi-Manesh, Hossein; Mountassif, Driss; Cerruti, Marta; Vali, Hojatollah; Faghihi, Shahab

2013-01-01

Genesis of natural biocomposite-based materials, such as bone, cartilage, and teeth, involves interactions between organic and inorganic systems. Natural biopolymers, such as peptide motif sequences, can be used as a template to direct the nucleation and crystallization of hydroxyapatite (HA). In this study, a natural motif sequence consisting of 13 amino acids present in the first helix of osteocalcin was selected based on its calcium binding ability and used as substrate for nucleation of HA crystals. The acidic (acidic osteocalcin-derived peptide (OSC)) and amidic (amidic osteocalcin-derived peptide (OSN)) forms of this sequence were synthesized to investigate the effects of different C termini on the process of biomineralization. Electron microscopy analyses show the formation of plate-like HA crystals with random size and shape in the presence of OSN. In contrast, spherical amorphous calcium phosphate is formed in the presence of OSC. Circular dichroism experiments indicate conformational changes of amidic peptide to an open and regular structure as a consequence of interaction with calcium and phosphate. There is no conformational change detectable in OSC. It is concluded that HA crystal formation, which only occurred in OSN, is attributable to C-terminal amidation of a natural peptide derived from osteocalcin. It is also proposed that natural peptides with the ability to promote biomineralization have the potential to be utilized in hard tissue regeneration. PMID:23362258

Au@Ag core-shell nanocubes for efficient plasmonic light scattering effect in low bandgap organic solar cells.

PubMed

Baek, Se-Woong; Park, Garam; Noh, Jonghyeon; Cho, Changsoon; Lee, Chun-Ho; Seo, Min-Kyo; Song, Hyunjoon; Lee, Jung-Yong

2014-04-22

In this report, we propose a metal-metal core-shell nanocube (NC) as an advanced plasmonic material for highly efficient organic solar cells (OSCs). We covered an Au core with a thin Ag shell as a scattering enhancer to build Au@Ag NCs, which showed stronger scattering efficiency than Au nanoparticles (AuNPs) throughout the visible range. Highly efficient plasmonic organic solar cells were fabricated by embedding Au@Ag NCs into an anodic buffer layer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), and the power conversion efficiency was enhanced to 6.3% from 5.3% in poly[N-9-hepta-decanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2,1,3-benzothiadiazole)] (PCDTBT):[6,6]-phenyl C71-butyric acid methyl ester (PC70BM) based OSCs and 9.2% from 7.9% in polythieno[3,4-b]thiophene/benzodithiophene (PTB7):PC70BM based OSCs. The Au@Ag NC plasmonic PCDTBT:PC70BM-based organic solar cells showed 2.2-fold higher external quantum efficiency enhancement compared to AuNPs devices at a wavelength of 450-700 nm due to the amplified plasmonic scattering effect. Finally, we proved the strongly enhanced plasmonic scattering efficiency of Au@Ag NCs embedded in organic solar cells via theoretical calculations and detailed optical measurements.