Student experiences of peer review marking of team projects

Peer review of students is a partial response to critics of group work who cite drawbacks of "free riders" and de-motivation. It is often used to motivate and focus students on their own development within a group work setting. Pressures of time, budget and student numbers often obviate deeper study of alternative assessment techniques. The study reported in this paper, made possible by an HEA grant, allowed for analysis of a peer review mechanism that had been operating for a number of years alongside a new web-based system. The paper reviews criticisms of peer review techniques in existing literature and outlines how student experiences of peer review were researched. Qualitative outcomes are discussed alongside an analysis of quantitative data from the systems used. Key conclusions from this research are that the data collection method made no significant difference to the reported student experiences of peer review or to the peer review marks. The findings update and strengthen previous literature and provide important new insights into the emotional perspective of students. The findings from this research are being used to aid development of the webbased system and to establish 'good practice' guidance on the deployment of this valuable and innovative technique

Opportunities for optics in integrated circuits applications

Optics potentially addresses two key problems in electronic chips and systems: interconnects and timing. Short optical pulses (e.g., picoseconds or shorter) offer particularly precise timing. Results are shown for optical and electrical four-phase clocking, with <1 ps rms jitter for the optical case

Studi storici dedicati a Orazio Cancila

Non accade sempre, e non è neppure necessario, che le raccolte di studi in onore di personalità del mondo degli studi trattino temi relativi o affini a quelli coltivati dalla personalità celebrata. Se, però, accade, si può certamente parlare di una felice circostanza o coincidenza, ma può accadere anche che tale circostanza o coincidenza sia significativa di qualcosa d’altro. E, ad esempio, può essere significativa del fatto che la personalità destinataria della raccolta si è posta o si è trovata al centro di sviluppi della storiografia contemporanea importanti anche perché rispondono a interessi diffusi negli studi e nella cultura del suo tempo. Della raccolta di studi per Orazio Cancila si può dire – credo – che ci si trova senz’altro in quest’ultimo caso, e, ciò, anche quando la formulazione letterale dei temi dei singoli contributi alla raccolta non sembra autorizzare una tale constatazione. ... È un bel panorama, ed è singolarmente conforme alla serie degli ampii e varii interessi storici di Cancila. (Dall'introduzione di Giuseppe Galasso

Scour features at wood bundles

Structures like blunt-nosed chevrons, log deflectors and double-winged log frames help in modifying the flow regime in the channel by concentrating the flow and increasing navigability. Moreover, they create scour pools in the downstream stilling basin, which can be used either as fish refuge or as an in-stream storage site for previously dredged material. In this respect, the use of wood debris in the channel in the form of wood bundles has gained attention for the ability of these structures to integrate into the surrounding fluvial habitat and to divert the flow partially towards the central part of the channel when placed in curves. Considering the absence of studies dealing with wood bundles as a restoration structure, the aim of this paper is to analyse the scour mechanism and equilibrium scour morphology of wood bundles in straight and curved channels. In doing so, a wide range of hydraulic conditions, structure positions and configurations were tested. Thereafter, dimensional analysis was carried out to derive useful empirical relationships to predict the maximum scour depth and length as well as the maximum dune height based on a novel, equivalent Froude number, which accounts for the effects of channel curvature and structure position. Moreover, the various resulting scour morphology types were classified, and conditions of their existence were determined depending on the abovementioned Froude number and other key hydraulic parameters

Increased levels of RNA oxidation enhance the reversion frequency in aging pro-apoptotic yeast mutants

Despite recent advances in understanding the complexity of RNA processes, regulation of the metabolism of oxidized cellular RNAs and the mechanisms through which oxidized ribonucleotides affect mRNA translation, and consequently cell viability, are not well characterized. We show here that the level of oxidized RNAs is markedly increased in a yeast decapping Kllsm4Δ1 mutant, which accumulates mRNAs, ages much faster that the wild type strain and undergoes regulated-cell-death. We also found that in Kllsm4Δ1 cells the mutation rate increases during chronological life span indicating that the capacity to han- dle oxidized RNAs in yeast declines with aging. Lowering intracellular ROS levels by antioxidants recovers the wild- type phenotype of mutant cells, including reduced amount of oxidized RNAs and lower mutation rate. Since mRNA oxidation was reported to occur in different neurodegen- erative diseases, decapping-deficient cells may represent a useful tool for deciphering molecular mechanisms of cell response to such conditions, providing new insights into RNA modification-based pathogenesis

Transition from a simple yield stress fluid to a thixotropic material

From MRI rheometry we show that a pure emulsion can be turned from a simple yield stress fluid to a thixotropic material by adding a small fraction of colloidal particles. The two fluids have the same behavior in the liquid regime but the loaded emulsion exhibits a critical shear rate below which no steady flows can be observed. For a stress below the yield stress, the pure emulsion abruptly stops flowing, whereas the viscosity of the loaded emulsion continuously increases in time, which leads to an apparent flow stoppage. This phenomenon can be very well represented by a model assuming a progressive increase of the number of droplet links via colloidal particles.Comment: Published in Physical Review E. http://pre.aps.org/abstract/PRE/v76/i5/e05140

Evolution of local scour downstream of Type A PK weir in non-cohesive sediments

Abstract A large-scale piano key weir laboratory study was conducted to investigate the evolution of the scour process occurring in the downstream basin for two non-cohesive granular bed materials, including the analysis of scour-hole geometry and patterns at equilibrium. It was observed that hydraulic conditions, particularly tailwater level, significantly affect the scour mechanisms and equilibrium morphology, eventually resulting in scour depths that exceeded the weir height. Unprecedented insights on the scour dynamics are also provided, along with tools to estimate the time evolution and maximum scour depth, its location in the streamwise direction, and the maximum scour length

Sicilia 1647. Voci, esempi, modelli di rivolta

La rivolta palermitana del maggio 1647 genera un vero e proprio modello. Ripreso, adattandolo e piegandolo alle esigneze locali, in gran parte dell'isola