Laboratory investigations of the thermal and non-thermal processing of condensed aromatic hydrocarbons in the interstellar medium

The thermal and non-thermal desorption of C6H6 has been investigated as a model for the behaviour of other aromatic hydrocarbons existing in the condensed phase in the interstellar medium. An interstellar dust grain mimic based on amorphous SiO2, to represent the interstellar silicate grain population, has been developed for use as a substrate in these experiments. Temperature programmed desorption experiments reveal a broad distribution of binding sites on this surface, with C6H6 desorbing thermally over a wide temperature range. The desorption from compact amorphous solid water displays simpler desorption kinetics with evidence for the formation of C6H6 islands on the water surface, demonstrating the importance of using realistic interstellar grain mimics in experiments probing surface sensitive interstellar processes. Kinetic parameters have been obtained for these systems, along with those for thicker multilayer films of ice. Photon irradiation of C6H6 / H2O layered ice systems at 250 nm results in the desorption of both species as observed using time-of-flight mass spectrometry. The molecules desorb with high translational energies which would represent a significant energy injection into the cold interstellar gas phase. Three desorption processes, desorption via direct adsorbate-, indirect adsorbate- and substrate-mediated desorption, are proposed for the observed desorption profiles. The desorption of H2O relies on energy transfer following photon absorption by a C6H6 molecule bound to a surface (H2O)n cluster, which results in the unimolecular decomposition of the complex. Kinetic simulations indicate that such processes may lead to an enhancement of photon-induced desorption at the edges of dense interstellar clouds. Experiments have also been performed to study the electron-stimulated desorption of molecules from C6H6 adsorbed on top of a water ice film. A highly efficient desorption channel with a cross-section in excess of 10-15 cm2 is in operation for low coverages of C6H6 and is attributed to the migration of excitons formed within the bulk of the H2O ice to the vacuum interface. A slower desorption component was also observed, which is attributed to a diffusion limited desorption step. These observations imply that electron stimulated desorption is likely to be an important non-thermal desorption process within dense clouds. No evidence for any chemical reaction products was observed through IR spectroscopy

A study to trial the use of inertial non-optical motion capture for ergonomic analysis of manufacturing work

It is going to be increasingly important for manufacturing system designers to incorporate human activity data and ergonomic analysis with other performance data in digital design modelling and system monitoring. However, traditional methods of capturing human activity data are not sufficiently accurate to meet the needs of digitised data analysis; qualitative data are subject to bias and imprecision, and optically derived data are hindered by occlusions caused by structures or other people in a working environment. Therefore, to meet contemporary needs for more accurate and objective data, inertial non-optical methods of measurement appear to offer a solution. This article describes a case study conducted within the aerospace manufacturing industry, where data on the human activities involved in aircraft wing system installations was first collected via traditional ethnographic methods and found to have limited accuracy and suitability for digital modelling, but similar human activity data subsequently collected using an automatic non-optical motion capture system in a more controlled environment showed better suitability. Results demonstrate the potential benefits of applying not only the inertial non-optical method in future digital modelling and performance monitoring but also the value of continuing to include qualitative analysis for richer interpretation of important explanatory factors

Digitisation of a moving assembly operation using multiple depth imaging sensors

Several manufacturing operations continue to be manual even in today’s highly automated industry because the complexity of such operations makes them heavily reliant on human skills, intellect and experience. This work aims to aid the automation of one such operation, the wheel loading operation on the trim and final moving assembly line in automotive production. It proposes a new method that uses multiple low-cost depth imaging sensors, commonly used in gaming, to acquire and digitise key shopfloor data associated with the operation, such as motion characteristics of the vehicle body on the moving conveyor line and the angular positions of alignment features of the parts to be assembled, in order to inform an intelligent automation solution. Experiments are conducted to test the performance of the proposed method across various assembly conditions, and the results are validated against an industry standard method using laser tracking. Some disadvantages of the method are discussed, and suggestions for improvements are suggested. The proposed method has the potential to be adopted to enable the automation of a wide range of moving assembly operations in multiple sectors of the manufacturing industry

The development and evaluation of Robot Light Skin: A novel robot signalling system to improve communication in industrial human–robot collaboration

In a human–robot collaborative production system, the robot could make request for interaction or notify the human operator if an uncertainty arises. Conventional industrial tower lights were designed for generic machine signalling purposes which may not be the ultimate solution for robot signalling in a collaborative setting. In this type of system, human operators could be monitoring multiple robots while carrying out a manual task so it is important to minimise the diversion of their attention. This paper presents a novel robot signalling solution, the Robot Light Skin (RLS),which is an integrated signalling system that could be used on most articulated robots. Our experiment was conducted to validate this concept in terms of its effect on improving operator's reaction time, hit-rate, awareness and task performance. The results showed that participants reacted faster to the RLS as well as achieved higher hit-rate. An eye tracker was used in the experiment which shows a reduction in diversion away from the manual task when using the RLS. Future study should explore the effect of the RLS concept on large-scale systems and multi-robot systems

Efficient Electron-promoted Desorption of Benzene from Water Ice Surfaces

We study the desorption of benzene from solid water surfaces during irradiation of ultrathin solid films with low energy electrons.</p

Seasonal Changes in Sleep Duration in African American and African College Students Living In Washington, D.C.

Duration of nocturnal melatonin secretion, a marker of “biological night” that relates to sleep duration, is longer in winter than in summer in patients with seasonal affective disorder (SAD), but not in healthy controls. In this study of African and African American college students, we hypothesized that students who met criteria for winter SAD or subsyndromal SAD (S-SAD) would report sleeping longer in winter than in summer. In addition, based on our previous observation that Africans report more “problems” with change in seasons than African Americans, we expected that the seasonal changes in sleep duration would be greater in African students than in African American students. Based on Seasonal Pattern Assessment Questionnaire (SPAQ) responses, African American and African college students in Washington, D.C. (N = 575) were grouped into a winter SAD/S-SAD group or a no winter diagnosis group, and winter and summer sleep length were determined. We conducted a 2 (season) × 2 (sex) × 2 (ethnicity) × 2 (winter diagnosis group) ANCOVA on reported sleep duration, controlling for age. Contrary to our hypothesis, we found that African and African American students with winter SAD/S-SAD report sleeping longer in the summer than in the winter. No differences in seasonality of sleep were found between African and African American students. Students with winter SAD or S-SAD may need to sacrifice sleep duration in the winter, when their academic functioning/efficiency may be impaired by syndromal or subsyndromal depression, in order to meet seasonally increased academic demands

Oil Biosynthesis in a Basal Angiosperm: Transcriptome Analysis of Persea Americana Mesocarp

The mechanism by which plants synthesize and store high amounts of triacylglycerols (TAG) in tissues other than seeds is not well understood. The comprehension of controls for carbon partitioning and oil accumulation in nonseed tissues is essential to generate oil-rich biomass in perennial bioenergy crops. Persea americana (avocado), a basal angiosperm with unique features that are ancestral to most flowering plants, stores ~ 70 % TAG per dry weight in its mesocarp, a nonseed tissue. Transcriptome analyses of select pathways, from generation of pyruvate and leading up to TAG accumulation, in mesocarp tissues of avocado was conducted and compared with that of oil-rich monocot (oil palm) and dicot (rapeseed and castor) tissues to identify tissue- and species-specific regulation and biosynthesis of TAG in plants

Religious Education, Big Ideas and the study of religion(s) and worldview(s)

This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.This article outlines the ‘Big Ideas’ approach to curriculum reform, as applied in the ‘Principles and Big Ideas of Science Education’ project (Harlen 2010). A critical analysis follows of the outcomes of the University of Exeter’s ‘Identifying Principles and Big Ideas for Religious Education’ project, which sought to apply the same approach to Religious Education (RE) in English schools (Wintersgill 2017). This project made great headway in generating ‘Big Ideas’ to inform and improve the selection and sequencing of RE curriculum content. However, its primary focus on subject content knowledge mean that ‘Big Ideas’ about epistemology and methodology are lacking. The article recommends an additional focus on multi-disciplinary, multi-methodological, inquiry-based, reflexive learning, which would ask why, how, where and by whom our ‘knowledge’ of religion(s) and worldview(s) is generated. In this regard, the article posits four ‘Big Ideas about the study of religion(s) and worldview(s)’ to highlight the symbiotic relationship between knowledge and knower, and to reject the false dichotomy between the object of study and method of study. In so doing, it draws upon the theoretical framework underpinning the ‘RE-searchers approach’ to primary school RE, which correspondingly exemplifies how such ideas can be taught in practice.The ‘Identifying Principles and Big Ideas for Religious Education’ project was supported by the St Luke’s College Foundation (016J-086). The ‘RE-searchers: A critical dialogic approach to Religious Education in primary schools’ project was supported by the Culham St. Gabriel’s Trust and Hockerill Education Foundation

Effect of natalizumab on disease progression in secondary progressive multiple sclerosis (ASCEND). a phase 3, randomised, double-blind, placebo-controlled trial with an open-label extension

Background: Although several disease-modifying treatments are available for relapsing multiple sclerosis, treatment effects have been more modest in progressive multiple sclerosis and have been observed particularly in actively relapsing subgroups or those with lesion activity on imaging. We sought to assess whether natalizumab slows disease progression in secondary progressive multiple sclerosis, independent of relapses. Methods: ASCEND was a phase 3, randomised, double-blind, placebo-controlled trial (part 1) with an optional 2 year open-label extension (part 2). Enrolled patients aged 18–58 years were natalizumab-naive and had secondary progressive multiple sclerosis for 2 years or more, disability progression unrelated to relapses in the previous year, and Expanded Disability Status Scale (EDSS) scores of 3·0–6·5. In part 1, patients from 163 sites in 17 countries were randomly assigned (1:1) to receive 300 mg intravenous natalizumab or placebo every 4 weeks for 2 years. Patients were stratified by site and by EDSS score (3·0–5·5 vs 6·0–6·5). Patients completing part 1 could enrol in part 2, in which all patients received natalizumab every 4 weeks until the end of the study. Throughout both parts, patients and staff were masked to the treatment received in part 1. The primary outcome in part 1 was the proportion of patients with sustained disability progression, assessed by one or more of three measures: the EDSS, Timed 25-Foot Walk (T25FW), and 9-Hole Peg Test (9HPT). The primary outcome in part 2 was the incidence of adverse events and serious adverse events. Efficacy and safety analyses were done in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01416181. Findings: Between Sept 13, 2011, and July 16, 2015, 889 patients were randomly assigned (n=440 to the natalizumab group, n=449 to the placebo group). In part 1, 195 (44%) of 439 natalizumab-treated patients and 214 (48%) of 448 placebo-treated patients had confirmed disability progression (odds ratio [OR] 0·86; 95% CI 0·66–1·13; p=0·287). No treatment effect was observed on the EDSS (OR 1·06, 95% CI 0·74–1·53; nominal p=0·753) or the T25FW (0·98, 0·74–1·30; nominal p=0·914) components of the primary outcome. However, natalizumab treatment reduced 9HPT progression (OR 0·56, 95% CI 0·40–0·80; nominal p=0·001). In part 1, 100 (22%) placebo-treated and 90 (20%) natalizumab-treated patients had serious adverse events. In part 2, 291 natalizumab-continuing patients and 274 natalizumab-naive patients received natalizumab (median follow-up 160 weeks [range 108–221]). Serious adverse events occurred in 39 (13%) patients continuing natalizumab and in 24 (9%) patients initiating natalizumab. Two deaths occurred in part 1, neither of which was considered related to study treatment. No progressive multifocal leukoencephalopathy occurred. Interpretation: Natalizumab treatment for secondary progressive multiple sclerosis did not reduce progression on the primary multicomponent disability endpoint in part 1, but it did reduce progression on its upper-limb component. Longer-term trials are needed to assess whether treatment of secondary progressive multiple sclerosis might produce benefits on additional disability components. Funding: Biogen

UBQLN2 mediates autophagy-independent protein aggregate clearance by the proteasome

Clearance of misfolded and aggregated proteins is central to cell survival. Here, we describe a new pathway for maintaining protein homeostasis mediated by the proteasome shuttle factor UBQLN2. The 26S proteasome degrades polyubiquitylated substrates by recognizing them through stoichiometrically bound ubiquitin receptors, but substrates are also delivered by reversibly bound shuttles. We aimed to determine why these parallel delivery mechanisms exist and found that UBQLN2 acts with the HSP70-HSP110 disaggregase machinery to clear protein aggregates via the 26S proteasome. UBQLN2 recognizes client-bound HSP70 and links it to the proteasome to allow for the degradation of aggregated and misfolded proteins. We further show that this process is active in the cell nucleus, where another system for aggregate clearance, autophagy, does not act. Finally, we found that mutations in UBQLN2, which lead to neurodegeneration in humans, are defective in chaperone binding, impair aggregate clearance, and cause cognitive deficits in mice