33 research outputs found
Jet color chemistry and anomalous baryon production in -collisions
We study anomalous high- baryon production in -collisions due to
formation of the two parton collinear system in the anti-sextet color
state for quark jets and system in the decuplet/anti-decuplet color states
for gluon jets. Fragmentation of these states, which are absent for
-collisions, after escaping from the quark-gluon plasma leads to baryon
production. Our qualitative estimates show that this mechanism can be
potentially important at RHIC and LHC energies.Comment: 20 pages, 4 figures, Eur.Phys.J. versio
Development and in vivo validation of tissue-engineered, small-diameter vascular grafts from decellularized aortae of fetal pigs and canine vascular endothelial cells
Factors confounding the assessment of reflection: a critical review
BACKGROUND: Reflection on experience is an increasingly critical part of professional development and lifelong learning. There is, however, continuing uncertainty about how best to put principle into practice, particularly as regards assessment. This article explores those uncertainties in order to find practical ways of assessing reflection. DISCUSSION: We critically review four problems: 1. Inconsistent definitions of reflection; 2. Lack of standards to determine (in)adequate reflection; 3. Factors that complicate assessment; 4. Internal and external contextual factors affecting the assessment of reflection. SUMMARY: To address the problem of inconsistency, we identified processes that were common to a number of widely quoted theories and synthesised a model, which yielded six indicators that could be used in assessment instruments. We arrived at the conclusion that, until further progress has been made in defining standards, assessment must depend on developing and communicating local consensus between stakeholders (students, practitioners, teachers, supervisors, curriculum developers) about what is expected in exercises and formal tests. Major factors that complicate assessment are the subjective nature of reflection's content and the dependency on descriptions by persons being assessed about their reflection process, without any objective means of verification. To counter these validity threats, we suggest that assessment should focus on generic process skills rather than the subjective content of reflection and where possible to consider objective information about the triggering situation to verify described reflections. Finally, internal and external contextual factors such as motivation, instruction, character of assessment (formative or summative) and the ability of individual learning environments to stimulate reflection should be considered
Wound dressings for a proteolytic-rich environment
Wound dressings have experienced continuous and significant changes over the years based on the knowledge of the biochemical events associated with chronic wounds. The development goes from natural
materials used to just cover and conceal the wound to interactive materials that can facilitate the healing process, addressing specific issues in non-healing wounds. These
new types of dressings often relate with the proteolytic wound environment and the bacteria load to enhance the healing. Recently, the wound dressing research is focusing on the replacement of synthetic polymers by natural protein materials to delivery bioactive agents to the wounds. This
article provides an overview on the novel protein-based wound dressings such as silk fibroin keratin and elastin.
The improved properties of these dressings, like the release of antibiotics and growth factors, are discussed. The different types of wounds and the effective parameters of
healing process will be reviewed
HLA Associations in 21-Hydroxylase Deficiency (Congenital and Late-Onset Adrenal Hyperplasia) in France
Using video-cases to assess student reflection: development and validation of an instrument
BACKGROUND: Reflection is a meta-cognitive process, characterized by: 1. Awareness of self and the situation; 2. Critical analysis and understanding of both self and the situation; 3. Development of new perspectives to inform future actions. Assessors can only access reflections indirectly through learners' verbal and/or written expressions. Being privy to the situation that triggered reflection could place reflective materials into context. Video-cases make that possible and, coupled with a scoring rubric, offer a reliable way of assessing reflection. METHODS: Fourth and fifth year undergraduate medical students were shown two interactive video-cases and asked to reflect on this experience, guided by six standard questions. The quality of students' reflections were scored using a specially developed Student Assessment of Reflection Scoring rubric (StARS(R)). Reflection scores were analyzed concerning interrater reliability and ability to discriminate between students. Further, the intra-rater reliability and case specificity were estimated by means of a generalizability study with rating and case scenario as facets. RESULTS: Reflection scores of 270 students ranged widely and interrater reliability was acceptable (Krippendorff's alpha = 0.88). The generalizability study suggested 3 or 4 cases were needed to obtain reliable ratings from 4th year students and >/= 6 cases from 5th year students. CONCLUSION: Use of StARS(R) to assess student reflections triggered by standardized video-cases had acceptable discriminative ability and reliability. We offer this practical method for assessing reflection summatively, and providing formative feedback in training situations