721 research outputs found
Application of feedback principles to marking proformas increases student efficacy, perceived utility of feedback, and likelihood of use
Pedagogical and psychological literature identifies numerous factors contributing to feedback effectiveness, including type, frequency, and specificity. Despite this wealth of research, feedback practice at universities is often reported as problematic or poor by students despite lecturers perceiving their feedback as useful. The present research employed a quantitative counterbalanced experimental design to compare the perceived utility of a pedagogically informed feedback proforma, designed to provide detailed, timely, and constructive feedback, to standard practice. Results suggest that the presentation of feedback is important to students; more functional and comprehensible feedback increases the likelihood of students using the feedback provided, and can reduce likely marking time per script without compromising perceived feedback quality. Further to this, post-submission feedback proformas increase studentsâ confidence in their ability to complete the assignment when provided alongside the assignment title. In summary, the research supports the application of principles of feedback in the provision of summative feedback to enhance studentsâ likelihood of use, perceived value of the feedback received, and confidence
Inter-simple sequence repeat (ISSR) loci mapping in the genome of perennial ryegrass
The aim of this study was to identify and characterize new ISSR markers and their loci in the genome of perennial ryegrass. A subsample of the VrnA F2 mapping family of perennial ryegrass comprising 92 individuals was used to develop a linkage map including inter-simple sequence repeat markers (ISSR). Twelve ISSR fragments out of 29 were mapped to the linkage groups (LG) LG1, LG2, LG4, LG6 and LG7. The total map length was 250.7 cM. Selected ISSR fragments were cloned by transformation into plasmid pTZ57R and sequenced. For four ISSRs, BLAST search revealed a significant similarity to coding regions of known sequences within the current DNA databases. An ISSR fragment of 580 bp, produced by the (GACA) 4 TC primer present on LG6, showed a 95% identity to the Avena sativa L. transposon and repetitive DNA linked to the receptor kinase gene. A 780 bp fragment generated by (TG) 8 RT primer demonstrated a 70% similarity to the Hordeum vulgare germin gene GerA. Inter-SSR mapping will provide useful information for gene targeting, quantitative trait loci mapping and marker-assisted selection in perennial ryegrass. Inter-simple sequence repeat (ISSR) loci mapping in the genome of perennial ryegrass
Surface layering of liquids: The role of surface tension
Recent measurements show that the free surfaces of liquid metals and alloys
are always layered, regardless of composition and surface tension; a result
supported by three decades of simulations and theory. Recent theoretical work
claims, however, that at low enough temperatures the free surfaces of all
liquids should become layered, unless preempted by bulk freezing. Using x-ray
reflectivity and diffuse scattering measurements we show that there is no
observable surface-induced layering in water at T=298 K, thus highlighting a
fundamental difference between dielectric and metallic liquids. The
implications of this result for the question in the title are discussed.Comment: 5 pages, 4 figures, to appear in Phys. Rev. B. 69 (2004
High specificity of BCL11B and GLG1 for EWSR1-FLI1 and EWSR1-ERG positive Ewing sarcoma
Ewing sarcoma (EwS) is an aggressive cancer displaying an undifferentiated small-round-cell histomorphology that can be easily confused with a broad spectrum of differential diagnoses. Using comparative transcriptomics and immunohistochemistry (IHC), we previously identified BCL11B and GLG1 as potential specific auxiliary IHC markers for EWSR1-FLI1-positive EwS. Herein, we aimed at validating the specificity of both markers in a far larger and independent cohort of EwS (including EWSR1-ERG-positive cases) and differential diagnoses. Furthermore, we evaluated their intra-tumoral expression heterogeneity. Thus, we stained tissue microarrays from 133 molecularly confirmed EwS cases and 320 samples from morphological mimics, as well as a series of patient-derived xenograft (PDX) models for BCL11B, GLG1, and CD99, and systematically assessed the immunoreactivity and optimal cut-offs for each marker. These analyses demonstrated that high BCL11B and/or GLG1 immunoreactivity in CD99-positive cases had a specificity of 97.5% and an accuracy of 87.4% for diagnosing EwS solely by IHC, and that the markers were expressed by EWSR1-ERG-positive EwS. Only little intra-tumoral heterogeneity in immunoreactivity was observed for differential diagnoses. These results indicate that BCL11B and GLG1 may help as specific auxiliary IHC markers in diagnosing EwS in conjunction with CD99, especially if confirmatory molecular diagnostics are not available.Barbara und Hubertus Trettner foundationDeutsche Forschungsgemeinschaft DFG 391665916Deutsche Stiftung fur junge Erwachsene mit KrebsDr. Leopold und Carmen Ellinger foundationDr. Rolf M. Schwiete foundationDr. Rudolf und Brigitte Zenner StiftungFriedrich-Baur foundationGerman Cancer Aid DKH-70112257German Cancer Aid DKH-108128German Cancer Aid DKH-70112018German Cancer Aid DKH-70113421
Criticality versus q in the 2+1-dimensional clock model
Using Monte Carlo simulations we have studied the clock model in
two different representations, the phase-representation and the
loop/dumbbell-gas (LDG) representation. We find that for the critical
exponents and for the specific heat and the correlation length,
respectively, take on values corresponding to the case , where
model, i.e. in terms of critical properties
the limiting behaviour is reached already at .Comment: Minor corrections; journal ref adde
Heterotic Compactification, An Algorithmic Approach
We approach string phenomenology from the perspective of computational
algebraic geometry, by providing new and efficient techniques for proving
stability and calculating particle spectra in heterotic compactifications. This
is done in the context of complete intersection Calabi-Yau manifolds in a
single projective space where we classify positive monad bundles. Using a
combination of analytic methods and computer algebra we prove stability for all
such bundles and compute the complete particle spectrum, including gauge
singlets. In particular, we find that the number of anti-generations vanishes
for all our bundles and that the spectrum is manifestly moduli-dependent.Comment: 36 pages, Late
A Review of Controlling Motivational Strategies from a Self-Determination Theory Perspective: Implications for Sports Coaches
The aim of this paper is to present a preliminary taxonomy of six controlling strategies, primarily based on the parental and educational literatures, which we believe are employed by coaches in sport contexts. Research in the sport and physical education literature has primarily focused on coachesâ autonomysupportive behaviours. Surprisingly, there has been very little research on the use of controlling strategies. A brief overview of the research which delineates each proposed strategy is presented, as are examples of the potential manifestation of the behaviours associated with each strategy in the context of sports coaching. In line with self-determination theory (Deci & Ryan, 1985; Ryan & Deci, 2002), we propose that coach behaviours employed to pressure or control athletes have the potential to thwart athletesâ feelings of autonomy, competence,and relatedness, which, in turn, undermine athletesâ self-determined motivation and contribute to the development of controlled motives. When athletes feel pressured to behave in a certain way, a variety of negative consequences are expected to ensue which are to the detriment of the athletesâ well-being. The purpose of this paper is to raise awareness and interest in the darker side of sport participation and to offer suggestions for future research in this area
Disordered Josephson Junctions of d-Wave Superconductors
We study the Josephson effect between weakly coupled d-wave superconductors
within the quasiclassical theory, in particular, the influence of interface
roughness on the current-phase relation and the critical current of mirror
junctions and asymmetric junctions. For mirror junctions the
temperature dependence of the critical current is non-monotonic in the limit of
low roughness, but monotonic for very rough interfaces. For
asymmetric junctions with a linear dimension much larger than the
superconducting coherence length we find a -like current-phase
relation, whereas for contacts on the scale of the coherence length or smaller
the usual -like behavior is observed. Our results compare well with
recent experimental observations.Comment: 10 pages, 12 figures; accepted for publication in Phys. Rev.
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