Author Correction: Coherent spin dynamics of electrons and holes in CsPbBr3 perovskite crystals.

The original version of this Article contained an error in Fig. 2c, in which the numbers on the y-axis were given in the wrong order: '800' at the bottom through to '0' at the top. This has been corrected in both the PDF and HTML versions of the Article.

Coherent spin dynamics of electrons and holes in CsPbBr3 perovskite crystals.

The lead halide perovskites demonstrate huge potential for optoelectronic applications, high energy radiation detectors, light emitting devices and solar energy harvesting. Those materials exhibit strong spin-orbit coupling enabling efficient optical orientation of carrier spins in perovskite-based devices with performance controlled by a magnetic field. Here we show that elaborated time-resolved spectroscopy involving strong magnetic fields can be successfully used for perovskites. We perform a comprehensive study of high-quality lead halide perovskite CsPbBr3 crystals by measuring the exciton and charge carrier g-factors, spin relaxation times and hyperfine interaction of carrier and nuclear spins by means of coherent spin dynamics. Owing to their 'inverted' band structure, perovskites represent appealing model systems for semiconductor spintronics exploiting the valence band hole spins, while in conventional semiconductors the conduction band electrons are considered for spin functionality.

Assessment of knowledge and practices about breastfeeding and weaning among working and non-working mothers.

OBJECTIVE: To assess the knowledge and practices of working and non-working mothers regarding breastfeeding and weaning. METHODS: This cross-sectional study involving working and non-working mothers was conducted from May 2015 to May 2016 at different hospitals of Karachi. Data was collected from women who had at least one child aged below 5 years and who had previously breastfed their child. Non-probability quota sampling technique was used. SPSS 20 was used for data analysis.. RESULTS: Of the 414 participants, 207(50%) were non-working while 207(50%) were working mothers. The overall mean age was 29.6±6.3 years. Moreover, 277(66.9%) mothers breastfed their youngest child and a significant difference was observed among the breastfeeding practices of working and non-working mothers (p<0.05). Bottle-feeding was adopted by 320(77.9%) mothers as an alternative method although 259(62.6%) mothers were aware about the harmful effects of bottle-feeding. Home-made products were used for weaning by 389(94%) mothers. CONCLUSIONS: Knowledge and practices regarding breastfeeding showed significant difference in most of the aspects between working and non-working mothers. As for weaning, both groups had the same knowledge and practices.

Human Papillomavirus Genotyping Testing Practice in 2014: Results of a College of American Pathologists National Survey.

CONTEXT: - College of American Pathologists (CAP) surveys are used to establish national benchmarks for laboratories. OBJECTIVE: - To investigate human papillomavirus (HPV) genotyping testing practice patterns in laboratories in 2014. DESIGN: - Data were analyzed from the CAP HPV Genotyping Practices Supplemental Questionnaire distributed to 749 laboratories participating in the CAP Human Papillomavirus (High Risk) for Cytology Program. RESULTS: - Six hundred four of 749 laboratories (80.6%) responded to the survey. More laboratories offered HPV genotyping testing and performed in-house HPV genotyping testing as compared to previous surveys. The Roche cobas HPV test was the most commonly used genotyping method (37.0%; 160 of 433), followed by Hologic Aptima HPV16 18/45 (26.1%; 113 of 433) and Hologic Cervista HPV16/18 (14.3%; 62 of 433). Most laboratories (287 of 399; 71.9%) offered HPV genotyping for high-risk HPV cases regardless of Papanicolaou (Pap) test results and patient age; this pattern was more common in laboratories using cobas. The remaining laboratories specifically offered testing to women with a negative Pap test result at age 30 years and older (65.2%, 73 of 112) or all ages (37.5%, 42 of 112). The median reporting rates of HPV16 and/or HPV18 positivity were 20.6%, 25.7%, 21.1%, and 57.4% for women with positive high-risk HPV adjunctive negative Pap results, atypical squamous cells of undermined significance, low-grade squamous intraepithelial lesion, and high-grade squamous lesion, respectively. CONCLUSIONS: - Human papillomavirus genotyping testing has increased. Roche cobas and Hologic Aptima genotype methods were the most common, and laboratories using cobas usually offered genotyping regardless of Pap test result and age. The data provide a baseline and trend of HPV genotyping test practices in 2014.

Misinterpretation Rates of High-Grade Squamous Intraepithelial Lesion in the College of American Pathologists Gynecologic PAP Education and PAP Proficiency Test Program.

Context .- Misinterpretation of high-grade squamous intraepithelial lesion (HSIL) is an important problem in daily practice and in the College of American Pathologists (CAP) PAP Proficiency Test (PAP-PT). Objective .- To investigate factors related to misinterpretation of HSIL through responses in a proficiency test versus an educational environment. Design .- We retrospectively evaluated 28 000 responses in the PAP Education Program (PAP-Edu) and 59 140 responses in PAP-PT from 1147 field-validated HSIL slides from 2007 to 2014. The related factors, such as program types, preparation types, participant types, and program years, were evaluated. Results .- Overall, 4.0% (2379 of 59 140) of responses for HSIL slides from PAP-PT were misinterpreted as either low-grade squamous intraepithelial lesion (LSIL) or negative, significantly more than those from PAP-Edu (3.2%; 898 of 28 000). However, the false-negative rate (misinterpreted as negative) was 0.9% (519 of 59 140) for PAP-PT, lower than that for PAP-Edu (1.0%; 266 of 28 000). The misinterpretation rates in PAP-PT trended down with time. Misinterpretation rates did not vary significantly by preparation methods. The misinterpretation rate for HSIL in the pathologists' responses was lower than that in cytotechnologists' in PAP-PT. More HSIL was misinterpreted as LSIL than as benign in both programs. Cytotechnologists interpreted HSIL as LSIL twice as much as pathologists. The most common false-negative misinterpretations were negative for intraepithelial lesion or malignancy and reparative change. Conclusions .- The higher LSIL misinterpretation rate by cytotechnologists may be related to the differences in reporting responsibilities and proficiency test grading criteria. The trend of gradually decreasing misinterpretation rates of a reference diagnosis of HSIL in the PAP-PT program may be related to higher test-taking confidence and better preparation through educational programs. The fact that pathologists performed better than cytotechnologists in PAP-PT, but not in PAP-Edu, may reflect a heightened approach and attentiveness in the test-taking environment for pathologists.

Application of a utility analysis to evaluate a novel assessment tool for clinically oriented physiology and pharmacology.

Multiple-choice questions are a gold-standard tool in medical school for assessment of knowledge and are the mainstay of licensing examinations. However, multiple-choice questions items can be criticized for lacking the ability to test higher-order learning or integrative thinking across multiple disciplines. Our objective was to develop a novel assessment that would address understanding of pathophysiology and pharmacology, evaluate learning at the levels of application, evaluation and synthesis, and allow students to demonstrate clinical reasoning. The rubric assesses student writeups of clinical case problems. The method is based on the physician's traditional postencounter Subjective, Objective, Assessment and Plan note. Students were required to correctly identify subjective and objective findings in authentic clinical case problems, to ascribe pathophysiological as well as pharmacological mechanisms to these findings, and to justify a list of differential diagnoses. A utility analysis was undertaken to evaluate the new assessment tool by appraising its reliability, validity, feasibility, cost effectiveness, acceptability, and educational impact using a mixed-method approach. The Subjective, Objective, Assessment and Plan assessment tool scored highly in terms of validity and educational impact and had acceptable levels of statistical reliability but was limited in terms of acceptance, feasibility, and cost effectiveness due to high time demands on expert graders and workload concerns from students. We conclude by making suggestions for improving the tool and recommend deployment of the instrument for low-stakes summative assessment or formative assessment.