Widening participation and English language proficiency : a convergence with implications for assessment practices in higher education

The widening participation agenda has important implications for those in Englishmedium higher education institutions responsible for the provision of English language support. Importantly, given the diverse nature of the ‘non-traditional’ student cohort that is the focus of this agenda, that section of the student population potentially requiring English language development extends beyond those students of non-English speaking backgrounds – traditionally the focus of such provision – to include native speakers of English whose language exhibits forms (dialectal characteristics) not necessarily in keeping with the expectations of the academy, or indeed the workplace post-graduation. In order to ensure that these students have access to language support resources that are squeezed by ever-present funding pressures, there needs to be a mechanism for identifying those most at risk due to weak language. This article considers some of the issues around the implementation of a post-enrolment English language assessment regime

Three-dimensional turbulent shock-wave : boundary-layer interactions in hypersonic flows.

Imperial Users onl

Dealing with diversity in higher education : awareness-raising and a linguistic perspective on teachers’ intercultural competence

Higher education institutions around the world are educating an increasingly diverse student population. While this responds to government discourse around widening participation and the need to internationalise, and while it can make for a stimulating teaching-learning environment, it can also present teachers with certain challenges that demand greater intercultural competence. This article considers how, as part of their intercultural repertoire, teachers – and by extension, students – can benefit from developing an understanding of language, and, in particular, the general principles governing how we mean in language and the lingua-cultural variability that impacts upon the process of doing so. It proposes awareness-raising activities as a way of promoting such understanding

An academic literacies argument for decentralizing EAP provision

English-medium universities have generally adopted centralized models of in-sessional English language provision, where expertise resides and is often delivered within language development units or as part of larger cognate departments, typically TESOL or Applied Linguistics departments. This arrangement might be seen as reflecting a one-size-fits-all study skills perspective on EAP, one that treats the development of student writing, in particular, as mastery of a set of skills that are generalizable across different disciplines. With the emergence of the ‘academic literacies’ perspective, this emphasis has shifted somewhat towards an approach that gives greater recognition to the variation which exists between the writing practices of different academic disciplines. This shift provides support for a move away from a centralized model of English language provision to a decentralized approach that brings with it a number of distinct benefits outlined in this article

Proton damage comparison of an e2v technologies n-channel and p-channel CCD204

Comparisons have been made of the relative degradation of charge transfer efficiency in n-channel and p-channel CCDs subjected to proton irradiation. The comparison described in this paper was made using e2v technologies plc. CCD204 devices fabricated using the same mask set. The device performance was compared over a range of temperatures using the same experimental arrangement and technique to provide a like-for-like comparison. The parallel transfer using the p-channel CCD was then optimized using a trap pumping technique to identify the optimal operating conditions at 153 K

Improvements to MOS CCD technology for future X-ray astronomy missions

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis is concerned with the development of MOS charge-coupled device (CCD) technology for future applications in X-ray astronomy. Of particular interest is increased detection efficiency of high energy X-ray photons and increased pixel readout speed for large area sensors. Chapter 2 reviews the generation of X-rays, methods for extra-terrestrial X-ray observations, detectors and provides an overview of X-ray astronomy missions. Chapter 3 discusses the CCD and introduces some of the recent technological developments that improve their overall performance for optical and X-ray photon detection. Chapter 4 presents the basic laboratory equipment and methods used to carry out the experimental work of this thesis. Chapter 5 presents the characterisation of new high resistivity devices that were manufactured by e2v technologies during the work of this thesis. Chapter 6 describes a method for estimating the depletion depth of a CCD by analysing the X-ray event patterns that are generated in CCD image data. Chapter 7 presents the equipment developed and experimental measurements taken to evaluate the high energy X-ray quantum efficiency of a high resistivity CCD. Finally, Chapter 8 describes the ongoing development and characterisation of low noise ASICs that are intended for use in future X-ray astronomy missions

U-Th dating of travertines on the Colorado Plateau: implications for the leakage of geologically stored CO2

In order to avoid the damaging climatic consequences of rising atmospheric CO2, and reduce current atmospheric CO2 concentrations to pre-industrial levels, anthropogenic CO2 emissions must be mitigated by capturing CO2 at power plants and storing it for thousands of years. Underground storage within deep geological formations, such as depleted gas and oil fields or deep saline aquifers, is the best understood solution for storage of CO2. In order for this method to gain more public and political acceptance it is important to characterise the potential causes, quantities and rates of CO2 release that could result if leakage were to occur from anthropogenic storage projects. This study examines two sites in the Colorado Plateau where faulted and actively leaking CO2 reservoirs provide natural analogues for failed anthropogenic storage sites. The two sites in question, the Little Grand Wash and northern Salt Wash graben faults are situated at the northern end of the Paradox Basin in Utah and represent classic three way traps due to juxtaposition of the shallow, north plunging Green River anticline against a set of east-west trending normal faults. In addition to active leakage sites in each area there are numerous fossilised travertine deposits. Along the Little Grand Wash fault the ancient mounds are restricted to the fault trace whereas ancient travertine mounds associated with the northern fault of the Salt Wash graben are far more numerous and occur up to ~530 m into the footwall of the fault. This more diffuse pattern of flow is due to the outcropping of unconfined aquifer units at the surface. A total of 45 U-Th dates from the majority of these travertine mounds provides a unique data set. The oldest deposits from the Little Grand Wash and northern Salt Wash graben faults produced ages of 113,912 ± 604 and 413,474 ± 15,127 years respectively. Repeat ages show reasonable reproducibility and analytical errors on results are of the order of 1% of the ages. The coupling of travertine elevation measurements with their radiometric ages gives an incision rate for each site. A rate of 0.342 m/ka for the Little Grand Wash fault relates directly to Green River incision and agrees with previous work on the Colorado Plateau, providing a further data point for characterisation of uplift of the province. For the northern fault of the Salt Wash graben a rate of 0.168 m/ka for the tributaries running through the area gives a robust method with which to estimate ages for un-dated mounds. The results of radiometric dating and incision rate age estimation of travertine mounds shows that leakage can last for timescales of 100,000’s of years, while high resolution U-Th dating of an individual mound demonstrated that leakage from a single point can last for a minimum of ~11,000 years. A range of travertine ages show that leakage to the surface has constantly switched location through time, while the presence of three mounds of distinct age at one location demonstrate that pathways can become repeatedly re-used over periods of ~45,000 years. There is no evidence of temporal periodicity in travertine deposition but there is a distinct spatial pattern of leakage as shown by localised similarities in the initial uranium chemistries of travertine mounds. Initial leakage is proximally located to the axial trace of the Green River anticline and subsequent leakage spreads from this central point along the fault plane in both east and west directions. The switching of fluid flow pathways to the surface can be explained by three main mechanisms: mineralisation, 3-phase interference of CO2 related fluid flow and seismically triggered alteration in dynamic strain acting upon the hydrology of the faults. These mechanisms have differing influences in each area - demonstrating that the behaviour of fluid flow switching in a system confined to damage zone fractures (Little Grand Wash fault) is different to a system leaking through an unconfined aquifer (northern fault of the Salt Wash graben). Coupling of travertine ages with estimates of their volumes provided a total worse case scenario for quantity of CO2 leakage of 6.2 x 10^6 ± 1.7 x 10^6 tonnes for the Little Grand Wash fault and 7.4 x 10^6 ± 2 x 10^6 tonnes for the northern fault of the Salt Wash graben. From these totals time averaged leakage rates of 55 ± 15 and 47 ± 13 tonnes/year were estimated for each fault. The leakage rate for the actively precipitating Crystal Geyser travertine (which is the result of anthropogenic exploration drilling) is estimated to be 3,153 ± 851 tonnes/year. These total and modern rates provide analogues for leakage via caprock failure and catastrophic wellbore failure. Applying them to large scale storage sites such as Weyburn and Gorgon revealed that for caprock failure complete leakage of these reservoirs will take place over timescales of 10^5-10^6 years, while for catastrophic failure of a single well complete leakage of these reservoirs could occur over as little as 10^3 – 10^4 years. This finding has important implications for the successful monitoring of anthropogenic storage sites

Neural indicators of fatigue in chronic diseases : A systematic review of MRI studies

The authors would like to thank the Sir Jules Thorn Charitable Trust for their financial support.Peer reviewedPublisher PD

Advanced techniques for the improvement of optical transmission systems

This thesis presents the experimental investigation into two novel techniques which can be incorporated into current optical systems. These techniques have the capability to improve the performance of transmission and the recovery of the transmitted signal at the receiver. The experimental objectives are described and the results for each technique are presented in two sections: The first experimental section is on work related to Ultra-long Raman Fibre lasers (ULRFLs). The fibre lasers have become an important research topic in recent years due to the significant improvement they give over lumped Raman amplification and their potential use in the development of system with large bandwidths and very low losses. The experiments involved the use of ASK and DPSK modulation types over a distance of 240km and DPSK over a distance of 320km. These results are compared to the current state of-the-art and against other types of ultra-long transmission amplification techniques. The second technique investigated involves asymmetrical, or offset, filtering. This technique is important because it deals with the strong filtering regimes that are a part of optical systems and networks in modern high-speed communications. It allows the improvement of the received signal by offsetting the central frequency of a filter after the output of a Delay Line Interferometer (DLI), which induces significant improvement in BER and/or Qvalues at the receiver and therefore an increase in signal quality. The experimental results are then concluded against the objectives of the experimental work and potential future work discussed

Widening participation in higher education

Higher education (HE) has the potential to be transformative: for individuals, local communities and for the wider society.[...