Recent Results From the EU POF-PLUS Project: Multi-Gigabit Transmission Over 1 mm Core Diameter Plastic Optical Fibers

Recent activity to achieve multi-gigabit transmission over 1 mm core diameter graded-index and step-index plastic optical fibers for distances up to 50 meters is reported in this paper. By employing a simple intensity-modulated direct-detection system with pulse amplitude or digital multi-tone modulation techniques, low-cost transceivers and easy to install large-core POFs, it is demonstrated that multi-gigabit transmission up to 10 Gbit/s over 1-mm core diameter POF infrastructure is feasible. The results presented in this paper were obtained in the EU FP7 POF-PLUS project, which focused on applications in different scenarios, such as in next-generation in-building residential networks and in datacom applications

Student Attitude to Audio Versus Written Feedback

First year Biology at the University of Glasgow consists of two courses, 1A and 1B, with an annual intake of 750-800 students. Both courses consist of lectures, practical lab sessions, tutorials and discussion groups. With such large numbers of students, teaching methods and delivery continually change and develop to ensure best delivery of the course content. As such, assessment and feedback systems also need to remain current and accessible to all. Timely, instructive and developmental feedback on student work is arguably the most powerful single influence on a student’s ability to learn. As part of the transition from school into university, feedback is a recognised method of maximising student potential (Hattie and Timperley, 2007). Research shows that increasing student numbers and associated rise in marking workloads, means that feedback can be slow in returning to the student and lacking quality/detail (Glover and Brown, 2006). From the markers perspective there is some evidence that students fail to engage with, misinterpret or ignore written feedback. We have carried out a pilot study to apply, and attempt to build upon, principles of good feedback practice to the assessment of coursework. To do this, an essay assignment was submitted online by Biology 1A students, marked and written feedback provided to all. A randomly selected group of students (10% of the cohort) also received audio feedback (electronic audio files were imbedded into the student work and returned to them by e-mail) on their submitted work. All students then completed an anonymous ‘Feedback’ questionnaire detailing their experiences with the feedback they received, with additional questions that were answered solely by the ‘audio group’ asking more specific questions about the effectiveness of the audio feedback. To carry out this study, new technologies were utilised and these will be demonstrated at the meeting along with the study conclusions. Hattie, J. and Timperley, H. (2007) The power of feedback. Review of Educational Research, 77, 81–112 Glover, C. and Brown, E. (2006). Written Feedback for Students: too much, too detailed or too incomprehensible to be effective? Bioscience Education, 7

Neuronal activity patterns in the mediodorsal thalamus and related cognitive circuits are modulated by metabotropic glutamate receptors.

The mediodorsal thalamus (MD) likely plays an important role in cognition as it receives abundant afferent connections from the amygdala and prefrontal cortex (PFC). Indeed, disturbed activity within the MD is thought to precipitate cognitive deficits associated with schizophrenia. As compounds acting at the Group II metabotropic glutamate (mGlu) receptors (subtypes mGlu2/mGlu3) have efficacy in animal models of schizophrenia, we investigated whether a Group II agonist and an mGlu2 positive allosteric modulator (PAM) could modulate MD activity. Extracellular single-unit recordings were made in vivo from MD neurones in anaesthetised rats. Responses were elicited by electrical stimulation of the PFC and/or amygdala, with Group II compounds locally applied as required. The Group II agonist reduced inhibition evoked in the MD: an effect manifested as an increase in short-latency responses, and a decrease in long-latency burst-firing. This disinhibitory action of the Group II receptors in the MD represents a mechanism of potential therapeutic importance as increased inhibition in the MD has been associated with cognitive deficit-onset. Furthermore, as co-application of the mGlu2 PAM did not potentiate the Group II agonist effects in the MD, we suggest that the Group II disinhibitory effect is majority-mediated via mGlu3. This heterogeneity in Group II receptor thalamic physiology bears consequence, as compounds active exclusively at the mGlu2 subtype are unlikely to perturb maladapted MD firing patterns associated with cognitive deficits, with activity at mGlu3 receptors possibly more appropriate. Indeed, polymorphisms in the mGlu3, but not the mGlu2, gene have been detected in patients with schizophrenia

Closing the feedback loop: physics undergraduates’ use of feedback comments on laboratory coursework

The laboratory notebooks of physics undergraduates taking two second-year practical courses were audited to discover whether they had used feedback comments in their subsequent coursework. Ninety-five per cent of the 37 students on the first course and 100% of the 14 students on the second course whose work was audited had used feedback. The marker’s comments were classified into two groups based on whether they addressed simple (mastery) or complex (developmental) learning outcomes. Mastery comments were more likely to be acted on than developmental comments which aimed to extend students’ skills and understanding to higher levels. This has implications for the use of feedback audit as a quality control process, since the feedback which is most commonly applied by students is not the most valuable for the development of higher order skills. Following reflection on the results for the first course, students taking the second course were given responsibility for checking their peers’ notebooks against preset criteria. Peer checking improved students’ marks but did not eliminate the need for mastery feedback. It is argued that a direct audit of students’ use of feedback is particularly valuable when undertaken by the teacher who provides the feedback

Models and measurements of energy-dependent quenching.

Energy-dependent quenching (qE) in photosystem II (PSII) is a pH-dependent response that enables plants to regulate light harvesting in response to rapid fluctuations in light intensity. In this review, we aim to provide a physical picture for understanding the interplay between the triggering of qE by a pH gradient across the thylakoid membrane and subsequent changes in PSII. We discuss how these changes alter the energy transfer network of chlorophyll in the grana membrane and allow it to switch between an unquenched and quenched state. Within this conceptual framework, we describe the biochemical and spectroscopic measurements and models that have been used to understand the mechanism of qE in plants with a focus on measurements of samples that perform qE in response to light. In addition, we address the outstanding questions and challenges in the field. One of the current challenges in gaining a full understanding of qE is the difficulty in simultaneously measuring both the photophysical mechanism of quenching and the physiological state of the thylakoid membrane. We suggest that new experimental and modeling efforts that can monitor the many processes that occur on multiple timescales and length scales will be important for elucidating the quantitative details of the mechanism of qE

CaosDB - Research Data Management for Complex, Changing, and Automated Research Workflows

Here we present CaosDB, a Research Data Management System (RDMS) designed to ensure seamless integration of inhomogeneous data sources and repositories of legacy data. Its primary purpose is the management of data from biomedical sciences, both from simulations and experiments during the complete research data lifecycle. An RDMS for this domain faces particular challenges: Research data arise in huge amounts, from a wide variety of sources, and traverse a highly branched path of further processing. To be accepted by its users, an RDMS must be built around workflows of the scientists and practices and thus support changes in workflow and data structure. Nevertheless it should encourage and support the development and observation of standards and furthermore facilitate the automation of data acquisition and processing with specialized software. The storage data model of an RDMS must reflect these complexities with appropriate semantics and ontologies while offering simple methods for finding, retrieving, and understanding relevant data. We show how CaosDB responds to these challenges and give an overview of the CaosDB Server, its data model and its easy-to-learn CaosDB Query Language. We briefly discuss the status of the implementation, how we currently use CaosDB, and how we plan to use and extend it

Cross-Linguistic Influence in the Bilingual Mental Lexicon: Evidence of Cognate Effects in the Phonetic Production and Processing of a Vowel Contrast.

The present study examines cognate effects in the phonetic production and processing of the Catalan back mid-vowel contrast (/o/-/ɔ/) by 24 early and highly proficient Spanish-Catalan bilinguals in Majorca (Spain). Participants completed a picture-naming task and a forced-choice lexical decision task in which they were presented with either words (e.g., /bɔsk/ "forest") or non-words based on real words, but with the alternate mid-vowel pair in stressed position ((*)/bosk/). The same cognate and non-cognate lexical items were included in the production and lexical decision experiments. The results indicate that even though these early bilinguals maintained the back mid-vowel contrast in their productions, they had great difficulties identifying non-words and real words based on the identity of the Catalan mid-vowel. The analyses revealed language dominance and cognate effects: Spanish-dominants exhibited higher error rates than Catalan-dominants, and production and lexical decision accuracy were also affected by cognate status. The present study contributes to the discussion of the organization of early bilinguals' dominant and non-dominant sound systems, and proposes that exemplar theoretic approaches can be extended to include bilingual lexical connections that account for the interactions between the phonetic and lexical levels of early bilingual individuals