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The Making Assessment Count (MAC) consortium- maximising assessment and feedback design by working together
The Making Assessment Count (MAC) project started at the University of Westminster in 2008. It sought to align staff and student expectations of feedback and support greater use of feed-forward approaches. A baseline analysis of staff views in the School of Life Sciences suggested that students did not make strategic use of the feedback they received. A similar analysis of the student position revealed that as a group they felt that the feedback provided to them was often insufficiently helpful. To address this dichotomy, a MAC process was developed in the School of Life Sciences and trialled with a cohort of about 350 first year undergraduate students. The process was based on a student-centred, three-stage model of feedback: Subject specific, Operational, and Strategic (SOS model). The student uses the subject tutor’s feedback on an assignment to complete an online self-review questionnaire delivered by a simple tool. The student answers are processed by a web application called e-Reflect to generate a further feedback report. Contained within this report are personalised graphical representations of performance, time management, satisfaction and other operational feedback designed to help the student reflect on their approach to preparation and completion of future work. The student then writes in an online learning journal, which is shared with their personal tutor to support the personal tutorial process and the student’s own development plan (PDP). Since the initial development and implementation of the MAC process within Life Sciences at Westminster, a consortium of universities has worked together to maximise the benefits of the project outcomes and collaboratively explore how the SOS model and e-Reflect can be exploited in different institutional and subject contexts. This paper presents and discusses an evaluation of the use of the MAC process within Life Sciences at Westminster from both staff and student perspective. In addition, the paper will show how the consortium is working to develop a number of scenarios for utilisation of the process as a whole as well as the key individual process components, the SOS model and e-Reflec
W18O49 Nanowires as Ultraviolet Photodetector
Photodetectors in a configuration of field effect transistor were fabricated based on individual W18O49 nanowires. Evaluation of electrical transport behavior indicates that the W18O49 nanowires are n-type semiconductors. The photodetectors show high sensitivity, stability and reversibility to ultraviolet (UV) light. A high photoconductive gain of 104 was obtained, and the photoconductivity is up to 60 nS upon exposure to 312 nm UV light with an intensity of 1.6 mW/cm2. Absorption of oxygen on the surface of W18O49 nanowires has a significant influence on the dark conductivity, and the ambient gas can remarkably change the conductivity of W18O49 nanowire. The results imply that W18O49 nanowires will be promising candidates for fabricating UV photodetectors
Volatile diterpene emission by two Mediterranean Cistaceae shrubs
Mediterranean vegetation emits a wide range of biogenic volatile organic compounds (BVOCs) among
which isoprenoids present quantitatively the most important compound class. Here, we investigated
the isoprenoid emission from two Mediterranean Cistaceae shrubs, Halimium halimifolium and Cistus
ladanifer, under controlled and natural conditions, respectively. For the first time, diurnal emission
patterns of the diterpene kaurene were detected in real-time by Proton-Transfer-Reaction-Timeof-
Flight-Mass-Spectrometer. Kaurene emissions were strongly variable among H. halimifolium
plants, ranging from 0.01 ± 0.003 to 0.06 ± 0.01 nmol m−2 s−1 in low and high emitting individuals,
respectively. They were in the same order of magnitude as monoterpene (0.01 ± 0.01 to 0.11 ± 0.04
nmol m−2 s−1) and sesquiterpene (0.01 ± 0.01 to 0.52 nmol m−2 s−1) emission rates. Comparable
range and variability was found for C. ladanifer under natural conditions. Labelling with 13C-pyruvate
suggested that emitted kaurene was not derived from de novo biosynthesis. The high kaurene content
in leaves, the weak relationship with ecophysiological parameters and the tendency of higher emissions
with increasing temperatures in the field indicate an emission from storage pools. This study highlights
significant emissions of kaurene from two Mediterranean shrub species, indicating that the release of
diterpenes into the atmosphere should probably deserve more attention in the futureinfo:eu-repo/semantics/publishedVersio
Synthesis of Well-Defined, Surfactant-Free Co<sub>3</sub>O<sub>4</sub> Nanoparticles:The Impact of Size and Manganese Promotion on Co<sub>3</sub>O<sub>4</sub> Reduction and Water Oxidation Activity
Abstract: A surfactant-free synthetic route has been developed to produce size-controlled, cube-like cobalt oxide nanoparticles of three different sizes in high yields. It was found that by using sodium nitrite as salt-mediating agent, near-quantitative yields could be obtained. The size of the nanoparticles could be altered from 11 to 22 nm by changing the cobalt concentration and reaction time. These surfactant-free nanoparticles form ideal substrates for facile deposition of further elements such as manganese. The effect of size of the cobalt oxide nanoparticles and the presence of manganese on the reducibility of cobalt oxide to metallic cobalt was investigated. Similarly, the effect of these parameters was investigated with a visible light promoted water oxidation system with cobalt oxide as catalyst, together with [Ru(bpy) 3] 2+ light harvester dye and an electron acceptor. Graphical Abstract: A novel surfactant-free synthetic route has been developed to produce size-controlled, cube shaped cobalt oxide nanoparticles in high yields. [Figure not available: see fulltext.]. </p
Alternative approaches to electrochromic devices for optical applications
Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 12th International Conference on Solid State Ionic
Numerical and experimental analysis of a solid desiccant wheel
The rotary desiccant dehumidifier is an important component which can be used
in air conditioning systems in order to reduce the electrical energy
consumption and introduce renewable energy sources. In this study a one
dimensional gas side resistance model is presented for predicting the
performance of the desiccant wheel. Measurements from two real sorption
wheels are used in order to validate the model. One wheel uses silica gel as
desiccant material and the other lithium chloride. The simulation results are
in good agreement with the experimental data. The model is used to compare
the counter flow with the co-current wheel arrangements and to explain why
the counter flow one is more efficient for air dehumidification
Increasing diagnostic accuracy with a cell block preparation from thin-layer endometrial cytology: A feasibility study
Objective To investigate (1), the feasibility of preparing cell blocks
by inverted filter sedimentation (IFS-CB) from endometrial samplings
processed by the ThinPrep (R) (TP) technique (Cytyc Corp., Boxborough,
Massachusetts, U.S.A), and (2) the possibility of increasing the
diagnostic accuracy of TP endometrial cytology by examining the tissue
architecture as an adjunctive method of detecting endometrial lesions.
Study Design Three hundred one endometrial samplings were obtained,
using the Endogyn endometrial device (Biogyn S. n.c., Italy), from
perimenopausal and postmenopausal women. The endometrial samplings were
collected in a vial with liquid fixative for the TP processing. One TP
slide was prepared from each case. If adequate material remained in the
vial after the TP slide preparation, it was processed for IFSCB
preparation.
Results IFS-CB preparation was processed in 263 cases (87%) with
adequate material. Diagnoses on IFS-CB preparations obtained by
endometrial sampling matched those of the hysterectomy specimens. The
addition of IFS-CB histology to the cytologic diagnosis by TP increased
the diagnostic accuracy of endometrial cytology to 96.3% and 100% for
benign/atrophic endometrium and adenocarcinoma, respectively (p = 0.39
and 0.46). In hyperplasia without atypia and hyperplasia with atypia,
the diagnostic accuracy increased significantly, to 96% and 95.3%,
respectively (p = 0 03 7 and < 0.001).
Conclusion This study illustrates the merit of linking TP cytology with
direct endometrial sampling, including small tissue fragments and
material adequate for IFS-CB preparation. TP cytology provides an
accurate cytologic diagnosis and the possibility of IFS-CB preparation,
which could be a valuable diagnostic adjunct to TP cytology
Evaluating the Technical and Environmental Capabilities of Geothermal Systems through Life Cycle Assessment
In these days of heightened environmental consciousness, many countries are shifting their focus towards renewable energy sources for both large-scale uses (such as power plants that generate electricity) and smaller-scale applications (e.g., building heating and cooling). In this light, it is not surprising that there is a growing interest in technologies that are reliant on non-conventional sources of power, such as geothermal energy. This study is making an effort to provide a comprehensive understanding of the possible advantages and multiple uses of geothermal energy systems, in the context of their technical and environmental evaluation through Life Cycle Assessment. A brief description of the analyzing methods and the tools used to study a particular system or application is presented. The geothermal technologies and the applications of specific systems are discussed in detail, providing their environmental advantages and their technical barriers as well. District and domestic heating systems cover a significant fraction of the geothermal energy potential. The majority of the discussed studies cover the electricity production as the most important application of geothermal energy. The overall conclusion of the current work is that geothermal energy is an extremely viable alternative that, combined with other renewable energy systems, may mitigate the negative effects of the existing energy mix worldwide
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