Map of research reviews: QCA Building the Evidence Base Project: September 2007 - March 2011

This is one of the major outputs of CUREE's literature review in the first year of the project to develop an evidence base for the curriculum in September 2007. As part of the Building the Evidence Base for a curriculum or the 21st Century project, this 'map' of existing reviews of research was aimed at harnessing evidence related to QCA’s new and wide ranging curriculum framework - it describes and analyses curriculum research; emerging key trends and patterns, results, methods, gaps in the evidence, and a bibliography

Awareness, aptitude, and French grammatical gender : an exploratory study

This study investigates the effects of awareness on the accurate assignment of French grammatical gender, and the importance of aptitude in explaining differences in awareness levels amongst second language (L2) learners. Previous awareness research using form-focused exposure tasks has found aware learners improve with the targeted linguistic feature as compared to unaware learners. In addition, research has always found some participants that are aware and some who appear to be unaware (Leow, 1997). Further research is needed on the effects of awareness with a variety of L2s and linguistic features (Rosa & Leow, 2004), and on the interaction amongst aptitude, awareness, and L2 learning (Robinson, 1997). The present study further investigated the effects of awareness on the subsequent L2 learning of French grammatical gender using a meaning-focused rather than form-focused exposure task. This research also addressed the issue of different awareness levels. Following Robinson, the role of aptitude in explaining these differences in awareness levels amongst L2 learners was explored. To investigate the effects of awareness on L2 learning, 36 beginner-French Anglophone adults completed a crossword following Leow (1997, 2000). The crossword provided participants with input on the reliably masculine noun ending eau (le plat eau ) in French, but they were not explicitly guided to look for this rule. Think-aloud protocols collected during the exposure task and two probe questions, one after the exposure task and one after the posttest, were analysed for evidence of awareness at one of two levels: unaware or aware. Learning was operationalised as pretest to posttest differences on a multiple-choice recognition task. There were two key findings: firstly, there were no differences in learning between the unaware and aware groups, and secondly, learners from both groups significantly improved in their ability to assign masculine gender to words they had encountered during the exposure task, but not to words that they had only encountered in the pretest. These findings run contrary to previous research on the effects of awareness (e.g. Leow; Rosa & O'Neill, 1999). Two possible explanations for these findings are that as the exposure task was meaning-focused rather than form-focused, participants did not verbalise their attention to form. Alternatively, it could be that French grammatical gender is being learnt as part of the exemplar-based system rather than the rule-based system (Skehan, 1998) and, as such, awareness may not be as important for linguistic features that are part of this system. To investigate possible reasons for awareness differences amongst participants, learners completed five aptitude tests, all used in previous research, that addressed the aptitude factors of attention control, working memory, phonological memory, grammatical sensitivity, and inductive language learning ability. Dörnyei & Skehan (2003) suggested that these five factors were important at the beginning stages of input processing, which were to be included in the exposure task. The results indicate that scores on the inductive language learning test predicted membership to the aware or unaware group accurately 72.22% of the time. No other test had a predictive value. This suggests that inductive ability may have played a role in promoting awareness of French grammatical gender during meaning-based exposure to French grammatical gender. Another finding is that the test for grammatical sensitivity (MLAT IV [Carroll & Sapon, 1957]) and the test for inductive (PLAB IV [Pimsleur, Reed, & Stansfield, 2004]) did not correlate. Aptitude research has often treated these two abilities together as analytic ability (Skehan, 1998), and used a grammatical sensitivity test to investigate the construct. The results from the present study suggest that these two tests may be tapping into different aptitude constructs and, as such, may need to be tested separately when investigating the role of individual differences to L2 learnin

Incidental, explicit, and implicit language learning during meaning-based exposure: Their effectiveness and relationship to individual cognitive abilities

Isolated grammar tasks develop different types of learning: incidental (pick up grammar), explicit (conscious learning) and implicit (unconscious learning). Cognitive abilities affecting the accuracy of these types of learning have been discussed (Robinson, 1997a). We know much less about learning during meaningful tasks, common in second language classrooms, during which language is used to understand or communicate information. This study employed tasks of this type to further knowledge of the: a.) incidental acquisition of form, b.) possibility of simultaneous explicit and implicit learning, c.) quantitative differences between explicit and implicit accuracy, d.) role of learner cognitive abilities on quantity and type of learning, and e.) effects of classification of type of learning on the results. Eighty-one Anglophone adults completed two crosswords and two reading passages presented using a semi-artificial language (Rebuschat, 2008), which ensured experimental control, and between-participant equal vocabulary knowledge. After, participants completed a surprise, timed grammaticality judgement test to measure learning. Type of learning (explicit and/or implicit) was assessed using three awareness measures (confidence ratings, source attributions, and verbal reports). Participants’ working memory, inductive ability, processing speed, and verbal reasoning were measured. The results demonstrated participants incidentally acquired some of the language. The majority of participants (n = 63) learnt the language explicitly and implicitly, and explicit learning was slightly more accurate. Cognitive abilities were unrelated to incidental acquisition, and the accuracy of explicit and implicit learning. However, inductive ability predicted the quantity of language processed explicitly positively and implicitly negatively. The findings further knowledge of the effectiveness of incidental, explicit, and implicit learning during language use. They demonstrate for the first time that adults learn language form using explicit and implicit processing simultaneously when focused on meaning. The small differences in accuracy of explicit and implicit learning suggest that when learning form is a by-product of understanding, implicitly-learnt information may be as accurate as explicitly-learnt information. Furthermore, as cognitive abilities did not affect the accuracy of incidental, explicit, and implicit learning, learning form whilst using may not disadvantage certain learners. However, as ability to induce patterns affects how information is processed, learners may benefit from practising pattern induction

DHA Supplementation Alone or in Combination with Other Nutrients Does not Modulate Cerebral Hemodynamics or Cognitive Function in Healthy Older Adults

A number of recent trials have demonstrated positive effects of dietary supplementation with the omega-3 polyunsaturated fatty acids (n-3 PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on measures of cognitive function in healthy young and older adults. One potential mechanism by which EPA, and DHA in particular, may exert these effects is via modulation of cerebral hemodynamics. In order to investigate the effects of DHA alone or provided as one component of a multinutrient supplement (also including Gingko biloba, phosphatidylserine and vitamins B9 and B12) on measures of cerebral hemodynamics and cognitive function, 86 healthy older adults aged 50–70 years who reported subjective memory deficits were recruited to take part in a six month daily dietary supplementation trial. Relative changes in the concentration of oxygenated hemoglobin and deoxygenated hemoglobin were assessed using Near Infrared Spectroscopy (NIRS) during the performance of cognitive tasks prior to and following the intervention period. Performance on the cognitive tasks was also assessed. No effect of either active treatment was found for any of the NIRS measures or on the cognitive performance tasks, although the study was limited by a number of factors. Further work should continue to evaluate more holistic approaches to cognitive aging

Seed bank dynamics govern persistence of Brassica hybrids in crop and natural habitats

Background and Aims: Gene flow from crops to their wild relatives has the potential to alter population growth rates and demography of hybrid populations, especially when a new crop has been genetically modified (GM). This study introduces a comprehensive approach to assess this potential for altered population fitness, and uses a combination of demographic data in two habitat types and mathematical (matrix) models that include crop rotations and outcrossing between parental species. Methods: Full life-cycle demographic rates, including seed bank survival, of non-GM Brassica rapa × B. napus F1 hybrids and their parent species were estimated from experiments in both agricultural and semi-natural habitats. Altered fitness potential was modelled using periodic matrices including crop rotations and outcrossing between parent species. Key Results: The demographic vital rates (i.e. for major stage transitions) of the hybrid population were intermediate between or lower than both parental species. The population growth rate (λ) of hybrids indicated decreases in both habitat types, and in a semi-natural habitat hybrids became extinct at two sites. Elasticity analyses indicated that seed bank survival was the greatest contributor to λ. In agricultural habitats, hybrid populations were projected to decline, but with persistence times up to 20 years. The seed bank survival rate was the main driver determining persistence. It was found that λ of the hybrids was largely determined by parental seed bank survival and subsequent replenishment of the hybrid population through outcrossing of B. rapa with B. napus. Conclusions: Hybrid persistence was found to be highly dependent on the seed bank, suggesting that targeting hybrid seed survival could be an important management option in controlling hybrid persistence. For local risk mitigation, an increased focus on the wild parent is suggested. Management actions, such as control of B. rapa, could indirectly reduce hybrid populations by blocking hybrid replenishment

Ct threshold values, a proxy for viral load in community SARS-CoV-2 cases, demonstrate wide variation across populations and over time.

BACKGROUND: Information on SARS-CoV-2 in representative community surveillance is limited, particularly cycle threshold (Ct) values (a proxy for viral load). METHODS: We included all positive nose and throat swabs 26 April 2020 to 13 March 2021 from the UK's national COVID-19 Infection Survey, tested by RT-PCR for the N, S, and ORF1ab genes. We investigated predictors of median Ct value using quantile regression. RESULTS: Of 3,312,159 nose and throat swabs, 27,902 (0.83%) were RT-PCR-positive, 10,317 (37%), 11,012 (40%), and 6550 (23%) for 3, 2, or 1 of the N, S, and ORF1ab genes, respectively, with median Ct = 29.2 (~215 copies/ml; IQR Ct = 21.9-32.8, 14-56,400 copies/ml). Independent predictors of lower Cts (i.e. higher viral load) included self-reported symptoms and more genes detected, with at most small effects of sex, ethnicity, and age. Single-gene positives almost invariably had Ct > 30, but Cts varied widely in triple-gene positives, including without symptoms. Population-level Cts changed over time, with declining Ct preceding increasing SARS-CoV-2 positivity. Of 6189 participants with IgG S-antibody tests post-first RT-PCR-positive, 4808 (78%) were ever antibody-positive; Cts were significantly higher in those remaining antibody negative. CONCLUSIONS: Marked variation in community SARS-CoV-2 Ct values suggests that they could be a useful epidemiological early-warning indicator. FUNDING: Department of Health and Social Care, National Institutes of Health Research, Huo Family Foundation, Medical Research Council UK; Wellcome Trust

Detection and Characterizationof Cellular Immune Responses Using Peptide–MHC Microarrays

The detection and characterization of antigen-specific T cell populations is critical for understanding the development and physiology of the immune system and its responses in health and disease. We have developed and tested a method that uses arrays of peptide–MHC complexes for the rapid identification, isolation, activation, and characterization of multiple antigen-specific populations of T cells. CD4(+) or CD8(+) lymphocytes can be captured in accordance with their ligand specificity using an array of peptide–MHC complexes printed on a film-coated glass surface. We have characterized the specificity and sensitivity of a peptide–MHC array using labeled lymphocytes from T cell receptor transgenic mice. In addition, we were able to use the array to detect a rare population of antigen-specific T cells following vaccination of a normal mouse. This approach should be useful for epitope discovery, as well as for characterization and analysis of multiple epitope-specific T cell populations during immune responses associated with viral and bacterial infection, cancer, autoimmunity, and vaccination

SARS-CoV-2 antibody trajectories after a single COVID-19 vaccination with and without prior infection

Given high SARS-CoV-2 incidence, coupled with slow and inequitable vaccine roll-out in many settings, there is a need for evidence to underpin optimum vaccine deployment, aiming to maximise global population immunity. We evaluate whether a single vaccination in individuals who have already been infected with SARS-CoV-2 generates similar initial and subsequent antibody responses to two vaccinations in those without prior infection. We compared anti-spike IgG antibody responses after a single vaccination with ChAdOx1, BNT162b2, or mRNA-1273 SARS-CoV-2 vaccines in the COVID-19 Infection Survey in the UK general population. In 100,849 adults median (50 (IQR: 37–63) years) receiving at least one vaccination, 13,404 (13.3%) had serological/PCR evidence of prior infection. Prior infection significantly boosted antibody responses, producing higher peak levels and/or longer half-lives after one dose of all three vaccines than those without prior infection receiving one or two vaccinations. In those with prior infection, the median time above the positivity threshold was >1 year after the first vaccination. Single-dose vaccination targeted to those previously infected may provide at least as good protection to two-dose vaccination among those without previous infection

Socio-cultural influences on the behaviour of South Asian women with diabetes in pregnancy: qualitative study using a multi-level theoretical approach

BACKGROUND: Diabetes in pregnancy is common in South Asians, especially those from low-income backgrounds, and leads to short-term morbidity and longer-term metabolic programming in mother and offspring. We sought to understand the multiple influences on behaviour (hence risks to metabolic health) of South Asian mothers and their unborn child, theorise how these influences interact and build over time, and inform the design of culturally congruent, multi-level interventions. METHODS: Our sample for this qualitative study was 45 women of Bangladeshi, Indian, Sri Lankan, or Pakistani origin aged 21-45 years with a history of diabetes in pregnancy, recruited from diabetes and antenatal services in two deprived London boroughs. Overall, 17 women shared their experiences of diabetes, pregnancy, and health services in group discussions and 28 women gave individual narrative interviews, facilitated by multilingual researchers, audiotaped, translated, and transcribed. Data were analysed using the constant comparative method, drawing on sociological and narrative theories. RESULTS: Key storylines (over-arching narratives) recurred across all ethnic groups studied. Short-term storylines depicted the experience of diabetic pregnancy as stressful, difficult to control, and associated with negative symptoms, especially tiredness. Taking exercise and restricting diet often worsened these symptoms and conflicted with advice from relatives and peers. Many women believed that exercise in pregnancy would damage the fetus and drain the mother's strength, and that eating would be strength-giving for mother and fetus. These short-term storylines were nested within medium-term storylines about family life, especially the cultural, practical, and material constraints of the traditional South Asian wife and mother role and past experiences of illness and healthcare, and within longer-term storylines about genetic, cultural, and material heritage - including migration, acculturation, and family memories of food insecurity. While peer advice was familiar, meaningful, and morally resonant, health education advice from clinicians was usually unfamiliar and devoid of cultural meaning. CONCLUSIONS: 'Behaviour change' interventions aimed at preventing and managing diabetes in South Asian women before and during pregnancy are likely to be ineffective if delivered in a socio-cultural vacuum. Individual education should be supplemented with community-level interventions to address the socio-material constraints and cultural frames within which behavioural 'choices' are made