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ABSTRACTWe studied the impact of delayed leaf senescence on the functioning of plants growing under conditions of nitrogen remobilization. Interactions between cytokinin metabolism, Rubisco and protein levels, photosynthesis and plant nitrogen partitioning were studied in transgenic tobacco (Nicotiana tabacum L.) plants showing delayed leaf senescence through a novel type of enhanced cytokinin syn-thesis, i.e. targeted to senescing leaves and negatively auto-regulated (PSAG12–IPT), thus preventing developmental abnormalities. Plants were grown with growth-limiting nitrogen supply. Compared to the wild-type, endogenous levels of free zeatin (Z)- and Z riboside (ZR)-type cytokinins were increased up to 15-fold (total ZR up to 100-fold) in senescing leaves, and twofold in younger leaves of PSAG12–IPT. In these plants, the senescence-associated declines in N, protein and Rubisco levels and photosynthesis rates were delayed. Senescing leaves accumulated more (15N-labelled) N than younger leaves, associated with reduced shoot N accumulation (–60%) and a partially inverted canopy N profile in PSAG12–IPT plants. While root N accumulation was not affected, N translocation to non-senescing leaves was progressively reduced. We discuss potential consequences of these modified sink–source relations, associated with delayed leaf senescence, for plant productivity and the efficiency of utilization of light and minerals. [ABSTRACT FROM AUTHOR]

Maintenance of ion gradients across plant membranes is considered to be an important process requiring respiratory energy in plant tissues. In order to test this hypothesis, roots of intact plants of potato (Solanum tuberosum L. cv. Alcmaria and cv. Pimpernel) were incubated in a closed circulation system. Electrical conductivity of the solution surrounding these roots was continuously monitored to determine total ion efflux into demineralized water. Anion efflux rate from the symplast was 35 neq (g dry weight)−1 s−1. In combination with literature data on the specific costs of ion transport, this efflux rate yields the respiration rate associated with re‐uptake balancing efflux (i. e. maintenance of cellular ion concentrations). The results suggest that energy costs associated with re‐uptake of ions may account for up to 25–50% of the total respiratory costs involved in ion influx. [ABSTRACT FROM AUTHOR]

The contribution of pre-defoliation reserves and current assimilatesto leaf and root growth was examined in Lolium perenne L. during regrowth after defoliation. Differential steady-state labelling with 13C (CO2with δ13C = - 0.0281 and - 0.0088) and 15N (NO3- with 1.0 and 0.368 atom percentage, i.e. δ15N = 1.742 and 0.0052, respectively) was applied for 2 weeks after defoliation. Rapidly growing tissues were isolated, i.e. the basal elongation and maturation zones ofthe most rapidly expanding leaves and young root tips, with a biomass turnover rate greater than 1 d-1. C and N weights of the elongation zone showed a transient decline. The dry matter and C concentration in fresh biomass of leaf growth zones transiently decreased by up to 25% 2 d after defoliation, while the N concentration remained constant. This 'dilution' of growth zone C indicates a decreased net influx of carbohydrates relative to growth-related influx of water and N in expanding cells, immediately after defoliation. Recovery of the total C and N weights of the leaf elongation zone coincided with net incorporation of currently absorbed C and N, as shown by the kinetics of δ13C and atom percentage 15N in the growth zones after defoliation. C isotope discrimination (δ13C ) in leaf growth zones was about 23 ‰, 1-2 ‰, higher than the δ in root tips. δ15N in the leaf and root growth zones was 10 ± 3‰. The leaf elongation zones (at 0-0.03 m from the tiller base) and the distant root tips (about 0.2 m from the base) exhibited similar kinetics of current C and N incorporation. The amount of pre-defoliation C and N in the growth zones, expressed as a fraction of total C and N, decreased from 1.0 to 0.5 at 3 (C) and 5 (N) d after defoliation, and to 0.1 at 5 (C) and 14 (N) d after defoliation. Thus, the dependen... [ABSTRACT FROM AUTHOR]

Aim: Psychosis is associated with significant health and societal costs. Early intervention in psychosis services (EIP) are highly effective in promoting recovery, yet substantial proportions of young people disengage. The current study aimed to develop and evaluate a novel engagement intervention in EIP services., Method: A qualitative investigation of facilitators and barriers to engagement in 68 first episode psychosis patients, family members and young people, and a Delphi consultation with 27 regional and national youth and psychosis service leads informed the development of the intervention. A mixed-methods feasibility-pilot study then compared engagement outcomes in 298 EIP service users in two cohorts: standard EIP versus standard EIP plus the novel early youth-engagement (EYE) intervention. A qualitative study explored intervention experiences in 22 randomly selected service users, carers and clinicians. A process evaluation explored delivery., Results: Disengagement was 24% in the standard EIP cohort compared to 14.5% in the standard EIP plus EYE intervention cohort. A 95% Bayesian credibility interval revealed a 95% probability that the true reduction in disengagement lay somewhere between 0% and 18%. The number needed to treat was 11, 95% CI [5, 242]. Use of the EYE resources was associated with engagement. Qualitiative feedback supported effects on communication, social network engagement, service user goals, mental health and well-being outcomes., Conclusion: The EYE intervention was designed from a service user, young person and carer perspective. Both qualitative and quantitative data support impacts on engagement. We now need to evaluate effectiveness, cost-effectiveness and implementation in a multi-site randomised controlled trial., (© 2024 The Author(s). Early Intervention in Psychiatry published by John Wiley & Sons Australia, Ltd.)

Objectives: Disengagement from Early Intervention in Psychosis (EIP) services is pronounced in individuals from racially minoritized or diverse ethnic backgrounds, lesbian, gay, bisexual, transgender, and queer or questioning individuals, and individuals from some religious or spiritual backgrounds. The Early Youth Engagement in first episode psychosis study (EYE-2) is a cluster randomized controlled trial that tests a new engagement intervention. The current study aimed to (i) explore perspectives of service users from diverse backgrounds in relation to spirituality, ethnicity, culture and sexuality on engagement and the EYE-2 approach and (ii) use an evidence-based adaptation framework to incorporate their needs and perspectives into the EYE-2 resources and training., Methods: This qualitative study used semi-structured interviews to explore service users' experiences and perspectives on EYE-2 approaches and resources. The study was conducted within EIP teams across three inner-city sites in England chosen to reflect diverse urban populations. Topic guides covered participant's identity, perceptions of EYE-2 resources, and experience of using mental health services. Transcribed interviews underwent thematic analysis., Results: In this study, 21 service users aged 18 to 35 (M = 25.4; SD = 5.5) participated in semi-structured interviews. Seven key themes were identified across the four domains of the cultural adaptation framework: Differing cognitions and beliefs; multiple facets of culture; language as a barrier to engagement; stigma and discrimination; adaptations to EYE-2 resources; trust in therapeutic alliance; and individual differences in therapeutic preferences., Conclusions: The emergent themes highlighted a need to cater to various aspects of cultural diversity when developing EIP materials and services., (© 2023 The Authors. British Journal of Clinical Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

Background: Many medical students may encounter a range of academic and personal challenges during their course of study, but very little is known about their experiences. Our aim was to review the literature to inform future scholarship and to inform policy change., Methods: A scoping review was conducted searching PubMed, MEDLINE, EMBASE, PsycInfo, British Education Index, Web of Science and ERIC for English language primary research with no date limits. This retrieved 822 papers of which eight met the requirements for inclusion in the review. Data were independently reviewed by two researchers and underwent thematic analysis by the research team., Results: Three major themes emerged. Theme 1: 'Identity preservation' addressed students' aim to preserve their sense of self in the face of academic difficulty and their tendency to seek support. This connected the apprehension many students expressed about their educational institutions to Theme 2: 'The dual role of the medical school'-medical schools are required to support struggling students but are predominantly seen as a punitive structure acting as the gatekeeper to a successful career in medicine. Students' apprehension and attempts to protect their identities within this complex landscape often resulted in 'maladaptive coping strategies' (Theme 3)., Conclusion: Understanding and exploring the academic challenges faced by medical students through their own experiences highlight the need for the development of more individualised remediation strategies. Educators may need to do more to bridge the gap between students and institutions. There is a need to build trust and to work with students to enhance their sense of self and remediate approaches to engagement with learning, rather than focusing efforts on success in assessments and progression., (© 2021 Association for the Study of Medical Education and John Wiley & Sons Ltd.)

Objectives: To assess the impact of a mental simulation intervention designed to reduce student alcohol consumption by asking participants to imagine potential positive outcomes of and/or strategic processes involved in not drinking during social occasions., Design: English university students aged 18-25 years (n = 211, Mage = 20 years) were randomly allocated to one of four intervention conditions. The dependent variables were weekly alcohol consumption, heavy episodic drinking (HED) frequency and frequency of social occasions at which participants did not drink alcohol when others were drinking alcohol ('episodic non-drinking'). Measures of alcohol-related prototypes (i.e., prototypical non-drinker, prototypical regular drinker) were used to compute sociability prototype difference scores as a potential mediator of any intervention effects. All measures were taken at baseline and at 2- and 4-week follow-up., Methods: Participants completed one of four exercises involving either imagining positive outcomes of non-drinking during a social occasion (outcome condition); imagining strategies required for non-drinking during a social occasion (process condition); imagining both positive outcomes and required strategies (combined condition); or completing a drinks diary task (control condition)., Results: Latent growth curve analyses revealed a more substantial rate of decrease in weekly unit consumption and HED frequency among outcome condition and process condition participants, relative to control condition participants. Non-significant differences were found between the combined condition and the control condition. Across the whole sample, an inverted U-shape trend indicated an initial increase in episodic non-drinking before it returned to baseline levels., Conclusion: This study provides preliminary evidence that mental simulation interventions focused on non-drinking can successfully promote behaviour change. Statement of contribution What is already known on this subject? UK drinking recommendations advise two 'dry days' per week (NHS, 2014). Benefits of, and strategies involved in, social non-drinking exist (Conroy & de Visser, 2014). Mental simulation interventions may help reduce student drinking (Hagger, Lonsdale, & Chatzisarantis, 2012; Hagger, Lonsdale, Koka et al., 2012). What does this study add? Demonstrates efficacy of a novel 'non-drinking' mental simulation exercise. Suggests that healthier alcohol prototypes can be encouraged via a health promotion intervention. Shows potential utility of 'episodic non-drinking' as an indicator of health-adherent drinking., (© 2015 The British Psychological Society.)

Swinging involves consensual mutual involvement in extra-dyadic sex. Jealousy in swinging couples is an interesting topic for social psychological research, because it is a common and acceptable response to a romantic partner's real or imagined infidelity. This qualitative study examined the management of jealousy among four active heterosexual swinging couples living in southern England. Participants highlighted the importance of discussion and negotiation to develop a shared couple identity and shared rules and boundaries that allowed them to manage jealousy so that they could better enjoy swinging. Rather than seeking to eliminate jealousy, swingers may manage their feelings of jealousy in order to increase sexual excitement and arousal. This study adds to our understanding of jealousy among swingers and the broader issue of jealousy in intimate relationships.

Objectives: To identify characteristics of individuals and characteristics of sexual encounters that predict whether people using contraception will also use condoms (dual use), and to determine whether dual use is prompted by concerns about unplanned pregnancy and/or sexually transmitted infections (STIs)., Design: A longitudinal prospective design was used to identify characteristics of individuals and characteristics of specific sexual encounters that predict condom use., Methods: A sample of 349 sexually active heterosexual young adults was recruited at universities and trade colleges in Melbourne, Australia. Participants completed a self-administered questionnaire, and a representative subsample (N=103) completed a structured condom use diary in which they reported on up to 10 instances of vaginal intercourse. Respondents reported use of condoms and other forms of contraception during 919 instances of vaginal intercourse., Results: In multivariate analyses, dual use of condoms in addition to other contraception was predicted by attitudes toward condoms, intentions to use condoms, partner type and discussion of condom use with sexual partners. Dual use was not related to greater concern about HIV/STIs or unplanned pregnancy., Conclusions: Encouraging heterosexual young adults to discuss condom use, and developing their skills for negotiation of condom use will increase rates of condom use, thereby reducing current high rates of unplanned pregnancy and STIs.