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Participation in a nationwide workplace step count competition is associated with improved physical fitness and mental wellbeing:a longitudinal, repeated-measures analysis
No full textBackground: The widely recognized health benefits of physical activity have led to the development of programs designed to increase activity levels within workplaces, where inactivity is often prevalent. We aimed to evaluate how participation in a Scotland-wide workplace walking program (Step Count Challenge [SCC]) influenced participants’ physical fitness and mental well-being. Methods: A 3-part multistudy design was employed, each using the 2-minute step test and Short Warwick-Edinburgh Mental Well-Being Scale to measure physical fitness and mental well-being, respectively. Study 1 (Spring, 8 wk, N = 475) and study 2 (Autumn, 4 wk, N = 336) were repeated-measures online-based nationwide cohort studies in 2021, and study 3 (N = 38) was an in-person experimental design with a control group in 2023. Results: Studies 1 and 2 found significant improvement in physical fitness (Spring: P < .001, η2 = .19; Autumn: P = .014, η2 = .13) and mental well-being (Spring: P < .001, η2 = .13; Autumn: P = .007, η2 = .05). Study 3 found a significant group × time interaction for physical fitness (P = .018, η2 = .172) such that the SCC group significantly improved over time (P = .042, η2 = .131) and found no significant differences for mental well- being. Conclusions: The findings of studies 1 and 2 demonstrate that participation in SCC is associated with a positive effect on physical fitness and mental well-being regardless of seasonal and duration differences. Study 3 also showed improvement in physical fitness, with a significantly greater increase for those who participated in SCC. This supports the promotion of future workplace walking programs.</p
Consequence, signification and insolubles in fourteenth-century logic
No full textForty years ago, Niels Green-Pedersen listed five different accounts of valid consequence, variously promoted by logicians in the early fourteenth century and discussed by Niels Drukken of Denmark in his commentary on Aristotle's Prior Analytics, written in Paris in the late 1330s. Two of these arguably fail to give defining conditions: truth preservation was shown by Buridan and others to be neither necessary nor sufficient; incompatibility of the opposite of the conclusion with the premises is merely circular if incompatibility is analysed in terms of consequence. Buridan proposed to define consequence in terms of preservation of signifying as things are. John Mair pinpointed a sophism which threatens to undermine this proposal. Speaking anachronistically, Bradwardine turned it around: he suggested that a necessary condition on consequence was that the premises signify everything the conclusion signifies. Dumbleton gave counterexamples to Bradwardine's postulates in which the conclusion arguably signifies more than, or even completely differently from the premises. Yet a long-standing tradition held that some species of validity depend on the conclusion being in some way contained in the premises. We explore the connection between signification and consequence and its role in solving the insolubles
Sexual selection, genomic evolution and population fitness in <i>Drosophila pseudoobscura</i>
No full textSexual selection shapes the genome in unique ways. It is also likely to have significant fitness consequences, such as purging deleterious mutations from the genome or conversely maintaining genetic load in a population via sexual conflict. Here, we examined what the influence of sexual selection has on genomic variation potentially underlying population fitness using experimentally evolved Drosophila pseudoobscura populations. Sexual selection was manipulated by keeping replicate lines in elevated polyandry or strict monogamy for approximately 200 generations followed by individual-based sequencing. Using pi (π), fixation index (Fst)and recombination rate measures, we confirmed signatures of selection were not dispersed but mainly localized to the third and X chromosome. Overall mutational load was similar between lines but our analysis of the distribution of fitness effects revealed considerable variation between lines and chromosomes. Furthermore, we found that the distribution of transposable elements differs between the lines, with a higher load in monogamous lines. Our results suggest that complex interactions between purifying selection and sexual conflict are shaping the genome, particularly on chromosome 3 and the sex chromosome; sexual selection influences divergence across chromosomes but in a more complex way than proposed by simple ‘purging’ of deleterious loci
Synthesis and growth mechanisms of (3,1)-graphene nanoribbons on Cu(111):insights from STM and DFT analysis
No full textWe present a comprehensive study on the bottom-up synthesis of chiral (3,1)-graphene nanoribbons (GNRs) on Cu(111) using two analogous precursors, 10,10'-dibromo-9,9'-bianthryl (DBBA) and bianthracene (BA). Through a temperature-programmed growth strategy supported by scanning tunnelling microscopy, we investigate the role of precursor diffusion, polymerization, and cyclodehydrogenation in GNR formation. Our results show that DBBA predominantly forms bisanthene due to restricted surface diffusion and premature cyclodehydrogenation, rendering it unsuitable for extended ribbon growth. In contrast, BA exhibits significantly higher surface mobility, leading to the formation of polyanthracene chains, which subsequently transform into long (3,1)-GNRs upon controlled annealing. We identify cyclodehydrogenation at chain termini as a key factor limiting ribbon length. Our findings provide new insights into optimizing growth conditions for extended GNRs on Cu(111), paving the way for their integration into future electronic and spintronic applications
Concerted conservation actions to support chimpanzee cultures
No full textChimpanzees were among the first animals recognized to have culture, and our understanding of the breadth of their cultural repertoire has grown significantly since the 1960s. Throughout their range, chimpanzee populations have come under increasing pressure, with their endangered status necessitating immediate and long-term conservation interventions. Recognizing the importance of diverse behavioural repertoires for chimpanzees’ survival, there has been a recent focus of conservation efforts on preserving their culturally transmitted behaviours and the environments in which they are exhibited. This article evaluates the practicality of developing conservation measures focused on chimpanzee culture. We highlight innovative conservation strategies aimed at integrating chimpanzee cultural behaviours into conservation policies. We review synergistic conservation initiatives led by the International Union for Conservation of Nature, the UN Convention on the Conservation of Migratory Species of Wild Animals and other international and local groups that share the goal of preserving chimpanzee populations and their cultural diversity. We underline how successful conservation implementation requires engagement and collaboration with a diverse group of interested or affected people. Finally, we provide recommendations aimed at guiding future efforts to incorporate animal cultures into conservation strategies
Net zero and the peatland carbon frontier:contesting incentives for ecosystem restoration in Scotland's Western Isles
No full textPeatlands have gained global political attention in recent years thanks to their capacity to store large quantities of carbon when in a healthy condition. To reach its ambitious target, Net Zero by 2045, the Scottish Government pledged to restore 250,000 hectares of its peatlands by 2030. Mobilising private finance is considered key to achieving this target. This paper critically assesses the need for ‘green’ finance in peatland restoration, asking how the progression of the ‘carbon frontier’ – the commodification of nature’s services – into the Highlands and Islands is influencing the perception and management of, and relations with, peatlands, particularly on crofting land. Evidence was gathered during seven weeks of fieldwork in the Isle of Lewis, participation in a variety of stakeholder events, semi-structured interviews with representatives of key stakeholder groups, and through an extensive policy review. Conceptualising the carbon frontier along three interrelated dimensions, (i) carbon obsession, (ii) carbon rush, and (iii) carbon stewardship, we contribute to the critical global scholarship on revealing the multiple faultlines of the natural capital paradigm central to net-zero strategies
Competitive accretion and the baryonic fraction in galaxies
No full textThe baryonic fraction of galaxies is observed to vary with the mass of their dark matter (DM) halo. Low-mass galaxies have low baryonic fractions that increase to a maximum for masses near 1012 M☉, and decrease thereafter with increasing galaxy mass. This trend is generally attributed to the action of feedback from star formation at the low end and of active galactic nuclei at the high-mass end. An alternative is that the baryonic fraction is at least partially due to the ability of galaxies to competitively accrete gas in a group or clustered environment. Most galaxies in a group including those of lower masses orbit the cluster centre at significant speeds and hence their accretion is limited by a Bondi–Hoyle-type process, M˙acc ∝ MDM2. In contrast, the few high-mass galaxies reside in the core of the cluster and accrete in a tidal accretion process, M˙acc ∝ MDM2/3. These two mechanisms result in a baryonic mass fraction that increases as MDM at low masses and decreases as MDM-1/3 at high masses. This model predicts that lower mass haloes in small-N groups should have higher baryonic fractions relative to those in large clusters.
Curcuminoid derivatives with a donor-acceptor-donor architecture:an outstanding platform for highly-efficient near-infrared electroluminescence and amplified spontaneous emission
No full textThe development of high-efficiency near-infrared (NIR) emitters for organic light-emitting diodes (OLEDs) and organic semiconductor lasers has become an important target in organic photonics. Herein, it is demonstrated that donor-acceptor-donor borondifluoride curcuminoid derivatives represent a versatile and simple platform for the molecular engineering of high-efficiency NIR emitters combining thermally-activated delayed fluorescence (TADF) with excellent electroluminescence properties and amplified spontaneous emission (ASE) activity. A series of donor-acceptor-donor curcuminoid compounds containing triphenylamino-substituents for the donor side groups and various acceptor units in the meso position were designed and synthesized. The investigation of the effects of the molecular structure on the TADF properties show that the nature of the substituents enables a fine tuning of the emission wavelengths while maintaining high photoluminescence quantum yield values. These NIR TADF dyes were used in OLEDs with an external quantum efficiency of almost 1% for a maximum emission wavelength of 797 nm. They also show a low threshold tuneable amplified spontaneous emission between 725 and 900 nm. Overall, this study provides new essential insights to rationalize the TADF activity of this family of NIR emitters and offers important prospects for designing the next generation of NIR TADF-OLEDs and organic semiconductor laser materials