Spin-dependent charge recombination along para-phenylene molecular wires

We have used an efficient new quantum mechanical method for radical pair recombination reactions to study the spin-dependent charge recombination along PTZ$^{\bullet+}$--Ph$_n$--PDI$^{\bullet-}$ molecular wires. By comparing our results to the experimental data of E. Weiss {\em et al.} [J. Am. Chem. Soc. {\bf 126}, 5577 (2004)], we are able to extract the spin-dependent (singlet and triplet) charge recombination rate constants for wires with $n=2-5$. These spin-dependent rate constants have not been extracted previously from the experimental data because they require fitting its magnetic field-dependence to the results of quantum spin dynamics simulations. We find that the triplet recombination rate constant decreases exponentially with the length of the wire, consistent with the superexchange mechanism of charge recombination. However, the singlet recombination rate constant is nearly independent of the length of the wire, suggesting that the singlet pathway is dominated by an incoherent hopping mechanism. A simple qualitative explanation for the different behaviours of the two spin-selective charge recombination pathways is provided in terms of Marcus theory. We also find evidence for a magnetic field-independent background contribution to the triplet yield of the charge recombination reaction, and suggest several possible explanations for it. Since none of these explanations is especially compelling given the available experimental evidence, and since the result appears to apply more generally to other molecular wires, we hope that this aspect of our study will stimulate further experimental work.Comment: 12 pages, 10 figure

Practical steps to building science capital in the primary classroom

An exploration of how meeting with engineers and scientists and other initiatives can help to increase science capita

Paired peer learning through engineering education outreach

© 2016 SEFI. Undergraduate education incorporating active learning and vicarious experience through education outreach presents a critical opportunity to influence future engineering teaching and practice capabilities. Engineering education outreach activities have been shown to have multiple benefits; increasing interest and engagement with science and engineering for school children, providing teachers with expert contributions to engineering subject knowledge, and developing professional generic skills for engineers such as communication and teamwork. This pilot intervention paired 10 pre-service teachers and 11 student engineers to enact engineering outreach in primary schools, reaching 269 children. A longitudinal mixed methods design was employed to measure change in attitudes and Education Outreach Self-Efficacy in student engineers; alongside attitudes, Teaching Engineering Self-Efficacy and Engineering Subject Knowledge Confidence in pre-service teachers. Highly significant improvements were noted in the pre-service teachers’ confidence and self-efficacy, while both the teachers and engineers qualitatively described benefits arising from the paired peer mentor model

Children as engineers: Paired peer mentors in primary schools final report summary July 2015

◾It’s been forecast that a further 100,000 new professionals are needed to fill the skills gap by 2020. It is becoming increasingly important that student engineers gain opportunities to practise their public engagement and education outreach skills to influence public perceptions of engineering, and connect science with society (Research Councils UK, 2010; National Coordinating Centre for Public Engagement, 2010).◾Teachers are a key audience with which to engage, as only 5% of primary school teachers have a science related degree (Department for Education, 2013). Although subject knowledge is not seen as essential for effective pedagogy, a lack of confidence and understanding can result in a style of teaching which reduces pupils’ performance, engagement and enjoyment with the subject (Ofsted, 2011).◾In this project, student engineers and pre-service teachers were paired up to mentor each other and enact hands-on challenges designed to demonstrate the Engineering Design Process to primary schoolchildren.◾The project appeared to be successful on all levels for the different participant groups. Quantitatively the student engineers showed an improvement in their perceived level of skills, with a 42% improvement in the proportion who felt they were now ‘fairly well equipped’ to undertake public engagement; over two-thirds (64%) of the engineers gave this rating following the project. Additionally, 70% of the engineers indicated that they thought they are now likely to be ‘more active’ in public engagement. Qualitatively, the student engineers indicated that that they had learnt organisational and communication skills through taking part, and felt that they had passed on some of their science and engineering subject knowledge and enthusiasm to the teachers and children.◾The paired peer partnership model was also positively reviewed by the pre-service teachers. Quantitative data indicated that the teachers showed significant increases in their science and engineering subject knowledge confidence levels as well as in teaching self-efficacy for both subjects. 80% of the pre-service teachers who participated stated that they would undertake similar work with children in the future. Many teachers asserted that the ‘expert’ knowledge gained had also benefitted and influenced the pupils in their class.◾Children who took part in the project had increased positive attitudes to the subjects of science and engineering in quantitative assessments. The project improved children’s knowledge of what an engineer does and their attitudes towards the profession through greater information about engineering and the experience of real life role models. The data also indicated a slight positive shift in children’s attitudes to science and engineering career aspirations along with gender and engineering identities

The structure and diversity of strain-level variation in vaginal bacteria

The vaginal microbiome plays an important role in human health and species of vaginal bacteria have been associated with reproductive disease. Strain-level variation is also thought to be important, but the diversity, structure and evolutionary history of vaginal strains is not as well characterized. We developed and validated an approach to measure strain variation from metagenomic data based on SNPs within the core genomes for six species of vaginal bacteria

Engineering science education: The impact of a paired peer approach on subject knowledge confidence and self-efficacy levels of student teachers

Teacher performance has been linked with both self-efficacy and subject knowledge confidence suggesting that it is important to address these aspects within initial teacher training programmes. This study investigated the development of pre-service teacher’s science and engineering subject knowledge confidence and teaching self-efficacy following participation in a paired-peer, multidisciplinary STEM project and assesses which aspects of the work may have resulted in any changes observed. A group of 10 pre-service teachers were paired with undergraduate engineering students to develop science through engineering challenges and to enact these with children. Multimethod pre and post evaluation assessed the impact of participation on the subject knowledge confidence and teaching self-efficacy levels of the pre-service teachers, alongside qualitatively exploring possible reasons for any changes. Results indicated that significant increases in both subject knowledge confidence and teaching self-efficacy had occurred. In exploring which aspects of the work may have contributed to these changes, data suggested that the paired-peer aspect of the project may have been beneficial. Immersing pre-service teachers in similar collaborative projects early in their career may provide opportunities to shape positive dispositions towards STEM subjects for pre-service teachers and so evaluations of how this can be built into teacher training programmes are required

Primary pathways: Elementary pupils’ aspiration to be engineers and STEM subject interest

Across Europe, there is concern about the number and diversity of pupils taking study routes leading to Engineering. There is growing evidence that these career choices begin to form at elementary school age (Moote et al., 2020). Science, maths and design and technology are seen as subject choices necessary for pupils’ progression into science, technology, engineering and mathematics (STEM) related occupations. Achievement in these subjects, identity, gender attitudes to the subjects, parents and informal activities may have an impact on these career choices. This mixed methods research draws on participants in the Children as Engineers project to investigate aspirations to a career in engineering and the links between these aspirations and attitudes to STEM subjects. It explores findings that suggest that there is little relationship between aspirations and positive attitudes to individual curriculum subjects. Pupils’ out-of-school activities and the links to aspirations in engineering are also researched and discussed. The article discusses the pupils’ rationales for these choices and the implications for intervention and informal engineering experiences that rely on a science and maths context for elementary school activities and for fostering interest in engineering

A scanning electron microscopic study of the sacculus and lagena in the ears of fifteen species of teleost fishes

The ulstrastructure of the saccular and lagenar maculae were studied in 15 species of teleost fishes, using the scanning electron microscope. Particular attention was paid to hair cell orientation patterns, composition of the ciliary bundles on the hair cells, hair cell distributions, and supporting cell types. The hair cells on both otolithic organs are divided into several groups with all of the hair cells in each group oriented in the same direction. The posterior region of the saccular macula in all species had dorsally oriented hair cells on the dorsal half of the macula and ventrally oriented hair cells on the ventral half. The cells on the anterior end of the macula were oriented anteriorly and posteriorly, with the posterior group, in most species, being on the dorsal half of the anterior region of the macula. There was considerable inter-specific variation upon this basic pattern. Inter-specific variation on the lagenar macula was considerably less than on the saccular macula. The basic pattern in all of the species includes one dorsal cell group and one ventral cell group. There are four more-or-less discrete ciliary bundles, each varying in the relative size of the kinocilia and stereocilia. Intermediary forms were also observed, making it difficult to differentiate ciliary bundles in some instances. It was apparent, however, that several of the ciliary bundles were found in particular macular regions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50266/1/1051530306_ftp.pd

The immune response to lumpy skin disease virus in cattle is influenced by inoculation route

Lumpy skin disease virus (LSDV) causes severe disease in cattle and water buffalo and is transmitted by hematophagous arthropod vectors. Detailed information of the adaptive and innate immune response to LSDV is limited, hampering the development of tools to control the disease. This study provides an in-depth analysis of the immune responses of calves experimentally inoculated with LSDV via either needle-inoculation or arthropod-inoculation using virus-positive Stomoxys calcitrans and Aedes aegypti vectors. Seven out of seventeen needle-inoculated calves (41%) developed clinical disease characterised by multifocal necrotic cutaneous nodules. In comparison 8/10 (80%) of the arthropod-inoculated calves developed clinical disease. A variable LSDV-specific IFN-γ immune response was detected in the needle-inoculated calves from 5 days post inoculation (dpi) onwards, with no difference between clinical calves (developed cutaneous lesions) and nonclinical calves (did not develop cutaneous lesions). In contrast a robust and uniform cell-mediated immune response was detected in all eight clinical arthropod-inoculated calves, with little response detected in the two nonclinical arthropod-inoculated calves. Neutralising antibodies against LSDV were detected in all inoculated cattle from 5-7 dpi. Comparison of the production of anti-LSDV IgM and IgG antibodies revealed no difference between clinical and nonclinical needle-inoculated calves, however a strong IgM response was evident in the nonclinical arthropod-inoculated calves but absent in the clinical arthropod-inoculated calves. This suggests that early IgM production is a correlate of protection in LSD. This study presents the first evidence of differences in the immune response between clinical and nonclinical cattle and highlights the importance of using a relevant transmission model when studying LSD

Development of an international standard set of outcome measures for patients with atrial fibrillation: a report of the International Consortium for Health Outcomes Measurement (ICHOM) atrial fibrillation working group.

AIMS: As health systems around the world increasingly look to measure and improve the value of care that they provide to patients, being able to measure the outcomes that matter most to patients is vital. To support the shift towards value-based health care in atrial fibrillation (AF), the International Consortium for Health Outcomes Measurement (ICHOM) assembled an international Working Group (WG) of 30 volunteers, including health professionals and patient representatives to develop a standardized minimum set of outcomes for benchmarking care delivery in clinical settings. METHODS AND RESULTS: Using an online-modified Delphi process, outcomes important to patients and health professionals were selected and categorized into (i) long-term consequences of disease outcomes, (ii) complications of treatment outcomes, and (iii) patient-reported outcomes. The WG identified demographic and clinical variables for use as case-mix risk adjusters. These included baseline demographics, comorbidities, cognitive function, date of diagnosis, disease duration, medications prescribed and AF procedures, as well as smoking, body mass index (BMI), alcohol intake, and physical activity. Where appropriate, and for ease of implementation, standardization of outcomes and case-mix variables was achieved using ICD codes. The standard set underwent an open review process in which over 80% of patients surveyed agreed with the outcomes captured by the standard set. CONCLUSION: Implementation of these consensus recommendations could help institutions to monitor, compare and improve the quality and delivery of chronic AF care. Their consistent definition and collection, using ICD codes where applicable, could also broaden the implementation of more patient-centric clinical outcomes research in AF