Generation Mixing of Sneutrinos in Heavier Chargino Decay

The heavier chargino decay could yield two charged leptons of different generations, owing to generation mixing of sneutrinos. We discuss the possibility of producing $e$ and $\mu$ through this process in near future collider experiments. The analyses are made systematically in the supersymmetric extension of the standard model without assuming a specific scenario for the mixing. Production of the heavier chargino is evaluated in $e^+e^-$ collisions. In the parameter region consistent with nonobservation of the radiative $\mu$ decay, sizable parts lead to a detectable branching ratio for the generation-changing decay of the heavier chargino.Comment: 22 pages, Revtex, 7 figures. v2: For the total width of the heavier chargino, the contribution from the decay into a charged slepton and a neutirno has been included. The figures (Figs. 2, 3, 4, 5), the equations and the related descriptions in sections II and III have been revised. Several references and equations added. v3: Several sentences of section I and V have been rewritten, conclusions unchange

Multiple Polar Cap Arcs: Akebono (Exos D) Observations

Akebono (Exos D) observations demonstrate that polar cap arcs sometimes have a fine structure, that is, multiple (double or triple) arcs with spacing of a few tens of kilometers. The multiple polar cap arcs are dominantly observed in the nightside polar cap region, suggesting that low background conductance favors the appearance of the structured arcs. A relationship between the spacing and the average energy of the precipitating electrons is investigated. Results show that a higher energy leads to a wider spacing. Akebono observations also show the existence of a downward current region embedded between upward current regions (arcs). Comparison of the observations with results from a coupled magnetosphere-ionosphere Sun-aligned arc model is made, which shows good qualitative agreement between the modeling and observational results on the spacing-energy dependence and the effect of background ionospheric conductance

Concepções e práticas de professores de ciências em relação ao trabalho prático, experimental, laboratorial e de campo

Este trabalho avaliou a situação da formação docente de um grupo de professores de Ciências no que concerne às quatro modalidades didáticas no ensino de Ciências: trabalho prático, experimental, laboratorial e de campo. Foram entrevistados, utilizando-se de um questionário, oito professores de Ciências de uma escola estadual e de uma particular do município de Maringá (Paraná-Brasil), com diferentes perfis e tempo de trabalho na área educacional. Trata-se de uma pesquisa qualitativa, com o intuito de verificar se as concepções e práticas destes professores em relação às modalidades didáticas apresentam lacunas que podem comprometer a construção do conhecimento científico pelos alunos. A análise dos dados foi realizada por meio do método de análise de conteúdo, que norteou a elaboração das discussões e conclusões apresentadas no trabalho

Processes of disposition development in K--5 teachers

Educators concur that teacher competency requires more than teaching knowledge and skills; competency requires appropriate professional dispositions. The development of professional dispositions is an expected outcome of teacher education programs. Since 2002, program accreditation has been contingent on documentation that prospective teachers have met national standards for dispositions. The body of educational research on disposition assessment has been growing. Research on disposition learning and development, however, has been impeded by the prevailing conceptualization of dispositions as fixed traits resistant to change. The present study conceptualized dispositions as malleable constructs within a theoretical framework that synthesized a cognitive model of thinking dispositions and a cultural-historical theory of development. The study aimed to explore and describe the processes by which a group of K-5 teachers developed professional dispositions. Participants were 30 elementary school teachers enrolled in a graduate teacher education course at a large, urban university in the southwestern United States. Most were female (80%), Caucasian (83%), teaching in a low-performing, urban school (83%), and completing their second year of teaching (93%). Median age was 24 and ranged from ages 22 to 44. A single-case study, embedded design was employed. The case was the process of disposition development, and the units of analyses were the affording and hindering mediators of disposition development. Data were collected from individual interviews, focus groups, and document reviews. Grounded theory methodology and a qualitative data analysis computer application were used to organize and analyze the data. Three key findings were identified. First, career commitment, which was derived from career awareness and interest, was necessary to initiate and maintain disposition development. Second, available mentors were necessary for beginning teachers to benefit from opportunities for learning that arose. Third, mediators of disposition development could be affordances or hindrances depending on the dynamic interplay between extrapersonal, intrapersonal, and interpersonal factors. The findings have practical implications for teacher educators who design curriculum and instruction and theoretical implications for educational researchers who investigate dispositions

Student-Led Discussions

According to constructivist learning theory informed by cognitive and educational psychology, the optimal conditions needed for learning include accurate assessment of student background knowledge; engaging, scaffolded activities; cognitive elaboration; and more knowledgeable others available to assist when needed.https://digitalscholarship.unlv.edu/btp_expo/1069/thumbnail.jp

The relationship between curvilinear structure enhancement and ridge detection methods

\ua9 2020, Springer-Verlag GmbH Germany, part of Springer Nature. Curvilinear structure detection and quantification is a large research area with many imaging applications in fields such as biology, medicine, and engineering. Curvilinear enhancement is often used as a pre-processing stage for ridge detection, but there has been little investigation into the relationship between enhancement and ridge detection. In this paper, we thoroughly evaluate the pair-wise combinations of different curvilinear enhancement and ridge detection methods across two highly varied datasets, as well as samples of three other datasets. In particular, we present the approaches complementing one another and the gained insights, which will aid researchers in designing generic ridge detectors

The impact of computed high b-value images on the diagnostic accuracy of DWI for prostate cancer: A receiver operating characteristics analysis.

To evaluate the performance of computed high b value diffusion-weighted images (DWI) in prostate cancer detection. 97 consecutive patients who had undergone multiparametric MRI of the prostate followed by biopsy were reviewed. Five radiologists independently scored 138 lesions on native high b-value images (b = 1200 s/mm2), apparent diffusion coefficient (ADC) maps, and computed high b-value images (contrast equivalent to b = 2000 s/mm2) to compare their diagnostic accuracy. Receiver operating characteristic (ROC) analysis and McNemar's test were performed to assess the relative performance of computed high b value DWI, native high b-value DWI and ADC maps. No significant difference existed in the area under the curve (AUC) for ROCs comparing B1200 (b = 1200 s/mm2) to computed B2000 (c-B2000) in 5 readers. In 4 of 5 readers c-B2000 had significantly increased sensitivity and/or decreased specificity compared to B1200 (McNemar's p < 0.05), at selected thresholds of interpretation. ADC maps were less accurate than B1200 or c-B2000 for 2 of 5 readers (P < 0.05). This study detected no consistent improvement in overall diagnostic accuracy using c-B2000, compared with B1200 images. Readers detected more cancer with c-B2000 images (increased sensitivity) but also more false positive findings (decreased specificity)

Histamine in diabetes: is it time to reconsider?

The first studies of histamine and diabetes date back to the 1950s. Since that time the involvement of histamine in diabetes was related to its well known vasoactive properties and permeability leakage effects. In particular, the first evidence for a correlation between histamine and diabetes arose in 1989 when an increase in plasma and leucocyte histamine content was observed. Limited independent evidence followed in the subsequent two decades, focusing on both histamine glyceamic control and macro- and microvascular complications of diabetes. However, recent observations have sparked the question whether it is time to reconsider the functional contribution of histamine in diabetes. We reveal an interesting upsurge in the field which provides scope for new insights into the role of histamine in diabetes