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Search for tt¯ H/ A→ tt¯ tt¯ production in the multilepton final state in proton–proton collisions at √s = 13 TeV with the ATLAS detector
A search for a new heavy scalar or pseudo-scalar Higgs boson (H/A) produced in association with a pair of top quarks, with the Higgs boson decaying into a pair of top quarks (H/A → tt¯) is reported. The search targets a final state with exactly two leptons with same-sign electric charges or at least three leptons. The analysed dataset corresponds to an integrated luminosity of 139 fb −1 of proton–proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC. Two multivariate classifiers are used to separate the signal from the background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of a type-II two-Higgs-doublet model. The observed (expected) upper limits at 95% confidence level on the tt¯ H/ A production cross-section times the branching ratio of H/A → tt¯ range between 14 (10) fb and 6 (5) fb for a heavy Higgs boson with mass between 400 GeV and 1000 GeV, respectively. Assuming that only one particle, either the scalar H or the pseudo-scalar A, contributes to the tt¯ tt¯ final state, values of tan β below 1.2 or 0.5 are excluded for a mass of 400 GeV or 1000 GeV, respectively. These exclusion ranges increase to tan β below 1.6 or 0.6 when both particles are considered. [Figure not available: see fulltext.]</p
Inclusive-photon production and its dependence on photon isolation in pp collisions at √s = 13 TeV using 139 fb<sup> −1</sup> of ATLAS data
Measurements of differential cross sections are presented for inclusive isolated-photon production in pp collisions at a centre-of-mass energy of 13 TeV provided by the LHC and using 139 fb −1 of data recorded by the ATLAS experiment. The cross sections are measured as functions of the photon transverse energy in different regions of photon pseudorapidity. The photons are required to be isolated by means of a fixed-cone method with two different cone radii. The dependence of the inclusive-photon production on the photon isolation is investigated by measuring the fiducial cross sections as functions of the isolation-cone radius and the ratios of the differential cross sections with different radii in different regions of photon pseudorapidity. The results presented in this paper constitute an improvement with respect to those published by ATLAS earlier: the measurements are provided for different isolation radii and with a more granular segmentation in photon pseudorapidity that can be exploited in improving the determination of the proton parton distribution functions. These improvements provide a more in-depth test of the theoretical predictions. Next-to-leading-order QCD predictions from JETPHOX and SHERPA and next-to-next-to-leading-order QCD predictions from NNLOJET are compared to the measurements, using several parameterisations of the proton parton distribution functions. The measured cross sections are well described by the fixed-order QCD predictions within the experimental and theoretical uncertainties in most of the investigated phase-space region. [Figure not available: see fulltext.]</p
Non-perturbative non-Gaussianity and primordial black holes
We present a non-perturbative method for calculating the abundance of primordial black holes given an arbitrary one-point probability distribution function for the primordial curvature perturbation, . A non-perturbative method is essential when considering non-Gaussianities that cannot be treated using a conventional perturbative expansion. To determine the full statistics of the density field, we relate ζ to a Gaussian field by equating the cumulative distribution functions. We consider two examples: a specific local-type non-Gaussian distribution arising from ultra slow roll models, and a general piecewise model for with an exponential tail. We demonstrate that the enhancement of primordial black hole formation is due to the intermediate regime, rather than the far tail. We also show that non-Gaussianity can have a significant impact on the shape of the primordial black hole mass distribution.</p
Solo Fathers and Mothers: An Exploration of Well-Being, Social Support and Social Approval
Research has begun to explore the experiences of single mothers by choice who choose to start a family alone and do so using donated gametes. However, very little is known about the experiences of single fathers by choice, and even less is known about how their experiences might compare to mothers in the same position. This exploratory study of single mothers (n = 19) and fathers (n = 17) by choice examined mental health and social support among mothers who used sperm donation, and fathers who used egg donation and surrogacy, to become parents. Data relating to their reasoning for pursuing solo parenthood, mental health, and social support were analyzed quantitatively. To further explore fathers’ experiences of being a solo parent, a thematic analysis was conducted exploring their descriptions of social responses to their family type. Regarding parental mental health, no statistically significant differences were found between mothers and fathers, and both groups of parents had sought out supportive networks, both before becoming a parent, and as a single parent. Fathers’ responses indicated that they received both supportive and negative reactions, although they generally perceived the majority of interactions to be positive. However, frequent references made by members of the public, or by the media, to their family type being new or different served to reproduce social scripts about normative family types. The study findings, despite the small sample size, contribute to a new understanding of the well-being and experiences of both mothers and fathers who choose to start their family and parent alone.</p
Documenting Families: Paper-Work in Family Display among Planned Single Father Families
This article extends existing sociological scholarship on doing and displaying family by developing the concept of documenting families. We suggest that documenting is conceptually rich insofar as it showcases the relationship, and tensions, between institutional practices and individual experiences of family display. Drawing on our research with men who became parents without partners, we argue that the process of documenting family is made especially evident in studies of what Finch originally referred to as ‘non-conventional’ family relationships. We explain that documenting sheds light not only on the official and unofficial means through which families are recognised on paper, but also on family practices as work – in this case paper-work – that involves negotiation between different social actors who are generally unequal in terms of their authority and agency to impose situational meaning.</p
Associations between psychological therapy outcomes for depression and incidence of dementia
Background Depression is an important, potentially modifiable dementia risk factor. However, it is not known whether effective treatment of depression through psychological therapies is associated with reduced dementia incidence. The aim of this study was to investigate associations between reduction in depressive symptoms following psychological therapy and the subsequent incidence of dementia. Methods National psychological therapy data were linked with hospital records of dementia diagnosis for 119808 people aged 65+. Participants received a course of psychological therapy treatment in Improving Access to Psychological Therapies (IAPT) services between 2012 and 2019. Cox proportional hazards models were run to test associations between improvement in depression following psychological therapy and incidence of dementia diagnosis up to eight years later. Results Improvements in depression following treatment were associated with reduced rates of dementia diagnosis up to 8 years later (HR = 0.88, 95% CI 0.83-0.94), after adjustment for key covariates. Strongest effects were observed for vascular dementia (HR = 0.86, 95% CI 0.77-0.97) compared with Alzheimer's disease (HR = 0.91, 95% CI 0.83-1.00). Conclusions Reliable improvement in depression across psychological therapy was associated with reduced incidence of future dementia. Results are consistent with at least two possibilities. Firstly, psychological interventions to improve symptoms of depression may have the potential to contribute to dementia risk reduction efforts. Secondly, psychological therapies may be less effective in people with underlying dementia pathology or they may be more likely to drop out of therapy (reverse causality). Tackling the under-representation of older people in psychological therapies and optimizing therapy outcomes is an important goal for future research.</p
Exploring teachers teaching reading comprehension: knowledge, behaviours and attitudes
There are few measures of teacher professional knowledge of reading comprehension, therefore little is known about the levels of teacher professional knowledge, their motivation and attitudes to teaching reading comprehension. The Knowledge, Behaviour and Attitudes Test for Reading Comprehension (KBAT-RC) was developed from a systematic literature review, in collaboration with researchers and practitioners. Findings from the first sample suggest that teachers prefer more tangible practices when teaching reading comprehension (teaching vocabulary, prediction and asking questions), in contrast to developing the inference skills and self-monitoring for meaning strategies of the children they teach. Implications for the development of teacher professional knowledge in reading comprehension are discussed.</p
Evidence of mutual non-verbal synchrony in learners with severe learning disability and autism, and their support workers: a motion energy analysis study
Introduction: Some research indicates that neurodivergent people are less likely than “neurotypical” people to adapt their movements to a partner’s movements to facilitate interpersonal motor synchrony. Researchers therefore suggest synchrony deficits underlie the social differences associated with autism and other neurodivergences. Intensive Interaction (II) is a client-led approach, where Learning Support Workers (LSW) follow the lead of learners to create balanced and reciprocal interactions.Methods: We aimed to examine the balance of synchrony in learners with autism and Severe Learning Disabilities and their LSWs in a special education college where learners had prior experience with II. Using Motion Energy Analysis, we assessed the degree to which each partner acted as a leader, and hence which partner acted as a follower, during moments of close synchrony.Results: Overall, learners and LSWs showed higher than chance synchrony. There were no differences in the degree to which each partner led the moments of synchrony, or the amount pairs synchronized with zero-lag, where there was no delay between each partners’ movements.Discussion: The equal balance of leading and following in the learner and LSW pairs demonstrates that both partners consistently adapted their movements to their partner’s movements to facilitate synchrony. The findings tentatively challenge the notion of a synchrony deficit in autism and suggest synchrony can be present in cross-neurotype pairs in comfortable and engaging conditions. We discuss the potential for client-led, movement-based approaches to support smooth interactions across neurotypes.</p
The associations of oxidative stress and inflammatory markers with obesity in Iranian population: MASHAD cohort study
Background: Low-grade inflammation and stress oxidative condition play a role in the pathogenesis of obesity, and the serum levels of these markers, such as pro-oxidant-antioxidant balance (PAB), high-sensitivity C-reactive protein (hs-CRP), and uric acid may indicate obesity progression. In this study, we aimed to investigate the relationship between obesity with PAB, hs-CRP, and uric acid in the Iranian population. Methods: This study was derived from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study. A total of 7985 subjects aged 35 to 65 years were divided into three groups according to body mass index (BMI) as: normal, overweight and obese groups. Anthropometric indices and biochemical parameters such as PAB, superoxide dismutase type 1 (SOD1), hs-CRP, and uric acid were measured in all the participants. We evaluated the association of obesity with inflammatory factors by using multivariate regression analysis. Also, those participants with hypertension, an endocrine disorder, history of cardiovascular diseases and diabetes mellitus were excluded from the study. Results: There was a positive significant correlation between BMI and serum PAB, hs-CRP and uric acid (p </p
Shifting norms, static behaviour: effects of dynamic norms on meat consumption
While decreasing their meat consumption is one of the most impactful behaviours an individual may carry out to reduce their carbon emissions, it is still a minority behaviour in many parts of the world. Research suggests that communicating information about changing 'dynamic' norms may be a useful tool for changing attitudes and behaviours in the direction of those currently held by the minority. This study uses a 2 × 2 mixed design (norm type [dynamic/static] × visual cue [present/absent, and a no-task control), and a follow-up assessment after one week to investigate the effect of making dynamic norms salient on various meat consumption outcomes: attitudes towards meat consumption, interest in reducing one's own meat consumption, intentions to reduce one's own meat consumption and self-reported meat consumption. We used an online sample of British participants (N = 1294), ranging in age 18-77 (M age = 39.97, s.d. age = 13.71; 55.8% female). We hypothesized that: (i) dynamic norms will positively influence meat consumption outcomes; (ii) visual cues will accentuate the difference between norm conditions; (iii) using a visual cue will enhance the effect of dynamic norms; and (iv) any effects of dynamic norms will endure over a period of one week. We found no positive effect of dynamic norms (versus static norms) on any outcome at time 1, and no positive effect on changes in outcomes from time 1 to time 2. However, we found a positive interaction of norm type and visual cue at time 1 (although not from time 1 to time 2): the addition of a visual cue to dynamic norm messages enhanced the positive effect of the message at time 1 (but did not enhance the changes occurring from time 1 to time 2). Analyses for changes in self-reported meat consumption did not reach our evidential threshold. We discuss the practical and theoretical implications of these findings.</p