β\beta--Radioactive Cosmic Rays in a diffusion model: test for a local bubble?

In the present paper, we extend the analysis of Maurin et al. (2001) and Donato et al. (2001) to the $\beta$-radioactive nuclei $^{10}$Be, $^{26}$Al and $^{36}$Cl. These species are be shown to be particularly sensitive to the properties of the local interstellar medium (LISM). As studies of the LISM suggest that we live in an underdense bubble of extent r_{hole} \sim 50 - 200 \unit{pc}, this local feature must be taken into account. We present a modified version of our diffusion model which describes the underdensity as a hole in the galactic disc. It is found that the presence of the bubble leads to a decrease in the radioactive fluxes which can be approximated by a simple factor $\exp(-r_{hole}/l_{rad})$ where $l_{rad}=\sqrt{K \gamma \tau_0}$ is the typical distance travelled by a radioactive nucleus before it decays. We find that each of the radioactive nuclei independently point towards a bubble radius \lesssim 100 \unit{pc}. If these nuclei are considered simultaneously, only models with a bubble radius r_{hole} \sim 60 - 100 \unit{pc} are marginally consistent with data. In particular, the standard case r_{hole}=0 \unit{pc} is disfavoured. Our main concern is about the consistency of the currently available data, especially $^{26}$Al/$^{27}$Al.Comment: 21 pages, 11 figures, Latex, macro aa.cls, to appear in A&

Student Collaboration and Teacher‐Directed Classroom Dynamic Assessment: A Complementary Pairing

This article examines collaboration during small‐group tasks with young language learners studying Spanish. After five days of classroom dynamic assessment (DA) targeting WH‐question formation, students worked in small groups on a collaborative writing task. This research sought to determine whether learners were able to mediate their peers during this task and if so, whether this mediation might be traced back to participation in classroom DA. Findings revealed that students drew upon collective knowledge to complete the task. While the learners did not appropriate forms of mediation used during DA, characteristics such as repetition and first language usage appeared in peer scaffolding. We conclude that classroom DA can be supplemented by small‐group tasks and that assistance, albeit in different forms, emerged in these two contexts

Effectiveness of iterative interventions to increase research productivity in one residency program.

BACKGROUND: The Accreditation Council for Graduate Medical Education requires residency programs to expose residents to research opportunities. OBJECTIVE: The purpose of this study was to assess the impact of a series of iterative interventions to increase scholarly activity in one internal medicine residency. METHODS: Retrospective analysis of the effectiveness of a series of interventions to increase resident and faculty scholarly productivity over a 14-year period was performed using quality improvement methodology. Outcomes measured were accepted regional and national abstracts and PubMed indexed manuscripts of residents and faculty. RESULTS: Initially, regional meeting abstracts increased and then were supplanted by national meeting abstracts. Sustained gains in manuscript productivity occurred in the eighth year of interventions, increasing from a baseline of 0.01 publications/FTE/year to 1.57 publications/FTE/year in the final year measured. Run chart analysis indicated special cause variation associated with the interventions performed. CONCLUSIONS: Programs attempting to stimulate research production among faculty and residents can choose among many interventions cited in the literature. Since success of any group of interventions is likely additive and may take years to show benefit, measuring outcomes using quality improvement methodology may be an effective way to determine success

Design of a clinical competency committee to maximize formative feedback.

BACKGROUND: As the next phase in the roll-out of Next Accreditation System, US residency programs are to develop Clinical Competency Committees (CCCs) to formally implement outcome-based medical education objectives in the resident assessment process. However, any changes to an assessment system must consider balancing formative and summative tensions, flexibility and standardization tensions, fairness and transparency to learners, and administrative burden for faculty. OBJECTIVES/METHODS: In this article, one program discusses the approach one internal medicine residency took to create a developmental model CCC. In this model, a learner\u27s mentor presents the argument for competence to the CCC, while a second reviewer presents challenges to that argument to the rest of the committee members. The CCC members provide other insights and make recommendations. The mentor presents the final committee recommendations to that resident, who then works with the mentor to develop a plan for future action. RESULTS: CCC second reviewers spent an average of 30.4 min (SD: 11.4) preparing for each resident\u27s discussion, a duty performed 5-7 times every 6 months. Faculty development was associated with an increase in the number of action-oriented comments in the meeting minutes (3.2-4.1 comments per resident, CONCLUSION: Developmental model CCCs may be feasible for residency programs, but faculty development may be necessary

Rater Perceptions of Bias Using the Multiple Mini-interview Format: a Qualitative Study

Introduction The Multiple Mini-Interview (MMI) format appears to mitigate individual rater biases. However, the format itself may introduce structural systematic bias, favoring extroverted personality types.  This study aimed to gain a better understanding of these biases from the perspective of the interviewer. Methods A sample of MMI interviewers participated in a series of primary and follow-up one-on-one semi-structured interviews.   Interviews pursued subjects of perception of biases (including norming; applicant personality, appearance and behavior; and interviewer personality) associated with the MMI process.  Emergent qualitative data analysis was performed using the constant-comparative method. Results A number of perceived biases were identified by subjects, sub-grouped into cultural factors, personality factors, perception of prior preparation, concerns with norming, and biases associated with specific applicant characteristics. Discussion While the MMI appears to help mitigate individual rater biases, our analysis suggests that raters perceive structural systematic biases may be introduced by the question type and format of the MMI itself.  Whether rater awareness of these biases mitigates them, and whether these herald other unconscious biases is unknown

Kaluza-Klein Dark Matter and Galactic Antiprotons

Extra dimensions offer new ways to address long-standing problems in beyond the standard model particle physics. In some classes of extra-dimensional models, the lightest Kaluza-Klein particle is a viable dark matter candidate. In this work, we study indirect detection of Kaluza-Klein dark matter via its annihilation into antiprotons. We use a sophisticated galactic cosmic ray diffusion model whose parameters are fully constrained by an extensive set of experimental data. We discuss how fluxes of cosmic antiprotons can be used to exclude low Kaluza-Klein masses.Comment: 14 pages, 7 figures, 3 table

β-catenin signaling and regulation of cyclin D1 promoter in NRK-49F cells transformed by down-regulation of the tumor suppressor lysyl oxidase

AbstractLysyl oxidase is the enzyme that is essential for collagen and elastin cross-linking. Previous investigations showed that lysyl oxidase is down-regulated in many human tumors and ras-transformed cells. Recently, we proved that antisense down-regulation of lysyl oxidase in NRK-49F cells induced phenotypic changes and oncogenic transformation, characterized by p21ras activation and β-catenin/cyclin D1 up-regulation. In the present paper, we examined β-catenin intracellular distribution and its association with E-cadherin. We observed an increased association between E-cadherin and β-catenin in the lysyl-oxidase down-regulated cells during serum starvation. Moreover, we found that β-catenin cytoplasmic and nuclear levels were increased, suggesting a failure of its down-regulation by the APC-GSK-3β system, in particular the GSK-3β phosphorylation of ser-33/37 and thr-41 of β-catenin. Finally, we investigated the mechanisms leading to the observed cyclin D1 up-regulation. We showed that in the antisense lysyl oxidase cells the cyclin D1 promoter was activated through the LEF and the ATF/CRE sites in the proximal promoter. While the promoter activation through LEF is compatible with β-catenin signaling, we investigated the possibility that the CRE-dependent activation might be linked to the down-regulation of lysyl oxidase. In fact, up-regulation of lysyl oxidase in a COS-7 cell model showed a significant diminution of the CREB protein binding to the cyclin D1 promoter, leading to a dramatic inhibition of its activity and a significant down-regulation of cyclin D1 protein level in vivo. Finally, our study describes some major anomalies occurring in lysyl oxidase down-regulated fibroblasts, related to β-catenin signaling and cyclin D1 expression

Interventions to increase research publications in graduate medical education trainees: a systematic review.

Introduction: Competency-based educational models recommend trainee exposure to research, but the best methods for Graduate Medical Education (GME) programs to accomplish this have not been clarified. The objective of this study was to quantify published interventions to generate resident research and compare effectiveness among those interventions. Material and methods: A systematic review of English-language articles of studies of GME programs was performed, describing resident research interventions and quantifying the number of publications as an outcome. Results: The search produced 13,688 potentially relevant articles, and included 47 articles in the final synthesis. Publication effectiveness was calculated as publications per year. The top ten programs for publication effectiveness were compared to others for interventions chosen. Interventions were characterized as research director, protected time, research requirement, research mentor, curricula, research assistant, biostatistician, information technology support, research fund, pay-for-performance plans, and celebration of accomplishments. Total number of different interventions was not significantly associated with primary outcome ( Conclusions: Leadership interventions (directors, curricula) are associated with successful GME research efforts

100 Miles of Wild: North Dakota Badlands Transcect

The North Dakota Badlands are little visited not just because of their distance from large populations, but also because they are physically challenging. The 100 Miles of Wild project had a simple aim: go to a little-visited area of North Dakota and discover firsthand the condition of the wild that inspired Roosevelt's effort to preserve wilderness for all Americans and the world