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The developmental trajectories of executive function from adolescence to old age
Get PDFFunding: This work was carried out with the support of a European Research Council grant to HF (Ref: CogSoCoAGE; 636458).Executive functions demonstrate variable developmental and aging profiles, with protracted development into early adulthood and declines in older age. However, relatively few studies have specifically included middle-aged adults in investigations of age-related differences in executive functions. This study explored the age-related differences in executive function from late childhood through to old age, allowing a more informed understanding of executive functions across the lifespan. Three hundred and fifty participants aged 10 to 86 years-old completed a battery of tasks assessing the specific roles of inhibitory control, working memory, cognitive flexibility, and planning. Results highlighted continued improvement in working memory capacity across adolescence and into young adulthood, followed by declines in both working memory and inhibitory control, beginning from as early as 30–40 years old and continuing into older age. Analyses of planning abilities showed continued improvement across adolescence and into young adulthood, followed by a decline in abilities across adulthood, with a small (positive) change in older age. Interestingly, a dissociation was found for cognitive flexibility; switch costs decreased, yet mixing costs increased across the lifespan. The results provide a description of the developmental differences in inhibitory control, working memory, cognitive flexibility and planning, above any effects of IQ or SES, and highlight the importance of including middle-aged adults in studies seeking to establish a more comprehensive picture of age-related differences in executive function.Peer reviewe
Molecular inventory of the environment of a young eruptive star : case study of the classical FU Orionis star V1057 Cyg
Get PDFFunding: Zs. M. Szabó acknowledges funding from a St. Leonards scholarship from the University of St. Andrews and C. J. C. acknowledges support from the STFC (grant ST/Y002229/1). Y. G. is supported by the Strategic Priority Research Program of the Chinese Academy of Sciences, Grant No. XDB0800301. This work is based on observations carried out under project number 060-21 (PI: Karl M. Menten) with the IRAM 30m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). This publication is based on data acquired with the Atacama Pathfinder Experiment (APEX) under programme ID M9530C_107, M9515A_108, and M9523C_109. APEX has been a collaboration between the Max-Planck-Institut fur Radioastronomie, the European Southern Observatory, and the Onsala Space Observatory. This work was also supported by the NKFIH excellence grant TKP2021-NKTA-64.Context . Studying accretion-driven episodic outbursts in young stellar objects (YSOs) is crucial for understanding the later stages of star and planet formation. FU Orionis-type objects (briefly, FUors) represent a small but rather central class of YSOs, whose outbursts are characterized by a rapid multi-magnitude increase in brightness at optical and near-infrared wavelengths. These outbursts may have a long-lasting influence on the chemistry and molecular inventory around eruptive young stars. However, no complete line survey in the millimeter wavelength range exists in the literature for more evolved (i.e., Class II) sources, in contrast to wide-band coverages at optical and near-infrared wavelengths. Aims . We carried out the first dedicated wide-band millimeter line survey toward the low-mass young eruptive star and classical FUor V1057 Cyg, which has the highest observed peak accretion rate among FUors. This source is known to have a molecular outflow, and it is associated with dense material. This makes it a good candidate for a search for molecular species. Methods . We performed a wide-band spectral line survey of V1057 Cyg with the IRAM 30 m telescope from ∼72 to ∼263 GHz (with a spatial resolution between ∼36″ and ∼10″), complemented by on-the-fly maps of selected molecules. We also recorded additional spectra around 219, 227, 291, and 344 GHz (with a spatial resolution between ∼30″ and ∼19″) with the APEX 12 m telescope. We conducted simple radiative transfer and population diagram analyses to derive the column densities and excitation temperatures. We constructed integrated-intensity maps of the emission from several molecular species, including those that reveal outflows. These maps and a 12CO (3–2) position-velocity diagram provide insight into the past outburst activity of the source. Results . We identified mainly simple C-, N-, O-, and S-bearing molecules, deuterated species, molecular ions, and complex organic molecules. Several molecular species (HCN, HC3N, and HNC) trace large-scale (∼2′) structures in the environment of V1057 Cyg with indications of small-scale fragmentation that remains unresolved by the single-dish data. The position-velocity diagram of 12CO shows concentrated knots, which may indicate past episodic outburst activity. We calculated the dynamical timescale of the outflow and found it to be on the order of a few ten thousand years (between 15 000 and 22 000 years), similar to other eruptive stars. This suggests that the outflow cannot result from the ongoing outburst alone, since the source has been in the current outburst for less than a century. The population diagrams for species such as CH3OH, H2CO, and HC3N indicate rotational temperatures that range from 8 K to 15 K and column densities that range from 1.4×1012 cm−2 to 2.8×1013 cm−2. Conclusions . With over 30 detected molecular species (including isotopologs), V1057 Cyg and its environment display a rich chemistry considering the more evolved state of this source compared to well-studied but younger (i.e., Class 0/I) FUors, e.g., V883 Ori. The results of our line survey show that V1057 Cyg is a good candidate for future interferometric observations aimed at resolving emission extents to constrain molecular freeze-out and to search for emission lines of water and additional complex organic molecules. Our observations highlight the potential of millimeter line surveys to characterize the chemistry of eruptive stars and their environments, including more evolved sources, and to complement optical and near-infrared studies in this way to improve current statistics of the molecular inventories of these objects.Peer reviewe
Proper names and metasemantic challenges : an idiolectal account
No full textThis dissertation offers an in depth discussion of a highly debated category of natural language expressions, which has been at the center of a significant attention in the last decades: proper names. The thesis presents a critical overview of the literature on these expressions' semantics and metasemantics, defending a referentialist, Millian, conception of names against some recently presented alternatives and offering a new metasemantic model to explain the complex mechanisms responsible for the determination of names' reference. In the first part of the thesis, I offer a detailed discussion of the two main alternatives to constant referentialist accounts in the contemporary literature, respectively represented by predicativist views (Chapter 1) and non-constant referentialist views (Chapter 2). After a brief assessment of their advantages and merits, I consider how these theories fair in comparison with more classical constant pictures, showing that, all things considered, the latter views still seem preferable. Then, in the second part of the thesis, I proceed to a discussion of the metasemantics of proper names, conceived as constant referential expressions in line with what argued in conclusion to Part 1. In particular, I introduce the semantic/metasemantic distinction and present some methodological considerations in Chapter 3, proceeding to a more detailed discussion of the main metasemantic accounts of names defended in the literature at the begin of Chapter 4, arguing against the social conception of reference-fixing dominant in the literature. Finally, I conclude this thesis discussion in Chapter 4 and 5 by presenting an alternative picture of names' metasemantics, focused on speakers abilities and idiolects. In particular, I present an account capable of capturing the conventional dimension of names and their relation to social practices, while avoiding the difficulties highlighted in Chapter 4
Evolvability under climate change : bone development and shape plasticity are heritable and correspond with performance in Arctic charr (Salvelinus alpinus)
Get PDFFunding: This study was funded by grants from the NatureScot, Royal Society, Carnegie Trust, Glasgow Natural History Society, and the University of Glasgow.Environmental conditions can impact the development of phenotypes and in turn the performance of individuals. Climate change, therefore, provides a pressing need to extend our understanding of how temperature will influence phenotypic variation. To address this, we assessed the impact of increased temperatures on ecologically significant phenotypic traits in Arctic charr (Salvelinus alpinus). We raised Arctic charr at 5°C and 9°C to simulate a predicted climate change scenario and examined temperature-induced variation in ossification, bone metabolism, skeletal morphology, and escape response. Fish reared at 9°C exhibited less cartilage and bone development at the same developmental stage, but also higher bone metabolism in localized regions. The higher temperature treatment also resulted in significant differences in craniofacial morphology, changes in the degree of variation, and fewer vertebrae. Both temperature regime and vertebral number affected escape response performance, with higher temperature leading to decreased latency. These findings demonstrate that climate change has the potential to impact development through multiple routes with the potential for plasticity and the release of cryptic genetic variation to have strong impacts on function through ecological performance and survival.Peer reviewe
Determining intrinsic sensitivity and the role of multiple scattering in speckle metrology
Get PDFFunding: This work was supported by funding from the Leverhulme Trust (RPG-2017-197), the UK Engineering and Physical Sciences Research Council (EP/P030017/1, EP/R004854/1), and the Australian Research Council (FL210100099).Speckle patterns are a powerful tool for high-precision metrology, as they allow remarkable performance in relatively simple setups. Nonetheless, researchers in this field follow rather distinct paths due to underappreciated general principles underlying speckle phenomena. Here, we advise on a universal metric of intrinsic speckle sensitivity, and on the advantages and disadvantages of multiple scattering. This will catalyse progress in speckle metrology but will also translate to other domains of disordered optics which are undergoing rapid developments at present.Peer reviewe
The complete songs of Robert Tannahill : a timely appreciation
Get PDFA remarkable project to record the Complete Songs of Robert Tannahill, the Paisley weaver-poet, has concluded with the 2024 release of a fifth and final disc, a fitting tribute marking the 250th anniversary of Tannahill’s birth. This review article discusses why Tannahill is an important and distinctive voice in the Scottish traditional song repertoire, and assesses the achievements of the recording project.Peer reviewe
Synthesis of a 2-(2-Trifluoroethoxyphenyl)oxazoline
Get PDFFunding: The study funded by EPSRC (UK) for a DTA studentship to ADH (Grant EP/L505079/1) and the EPSRC UK National Mass Spectrometry Facility at Swansea University.The title compound has been prepared in four steps starting from ethyl 2-fluorobenzoate. The final product as well as the intermediates are fully characterised by spectroscopic methods with the 1H and 13C NMR spectra featuring coupling to 19F being particularly informative.Peer reviewe
Norovirus-mediated translation repression promotes macrophage cell death
Get PDFFunding: JMM and PAW were funded by the National Health and Medical Research Council of Australia, grant number 1123135. JMD was supported by a PhD stipend provided by the University of Melbourne and the Miller Foundation.Norovirus infection is characterised by a rapid onset of disease and the development of debilitating symptoms including projectile vomiting and diffuse diarrhoea. Vaccines and antivirals are sorely lacking and developments in these areas are hampered by the lack of an adequate cell culture system to investigate human norovirus replication and pathogenesis. Herein, we describe how the model norovirus, Mouse norovirus (MNV), produces a viral protein, NS3, with the functional capacity to attenuate host protein translation which invokes the activation of cell death via apoptosis. We show that this function of NS3 is conserved between human and mouse viruses and map the protein domain attributable to this function. Our study highlights a critical viral protein that mediates crucial activities during replication, potentially identifying NS3 as a worthy target for antiviral drug development.Peer reviewe
Blending the real world and the virtual world : exploring the role of flow in augmented reality experiences
Get PDFThis study examines the ‘sweet spot’ of augmented reality (AR) through the lens of flow theory and has two primary objectives. First, the study seeks to determine whether investment in AR technologies is warranted by exploring flow in both an AR and a traditional shopping context. Second, the study examines the unique capabilities of AR to facilitate an enhanced state of flow and its positive influence across several consumer outcomes. To achieve these objectives, a commercially available AR app was utilized to conduct an online, between-subjects experiment with 500 participants. Partial least squares structural equation modeling was used to analyze the predictor variables of consumer flow, as well as the impact of flow across several consumer outcomes. Managerial and practical conclusions for marketers and designers are provided to support the creation and execution of AR technology within consumer contexts.Peer reviewe
Ubiquitylation of RIPK3 beyond-the-RHIM can limit RIPK3 activity and cell death
Get PDFFunding: The generation of the Ripk3 K469R/K469R mice used in this study was supported by Phenomics Australia and the Australian Government through the National Collaborative Research Infrastructure Strategy ( NCRIS ) program. MJH is a National Health and Medical Research Council of Australia ( NHMRC ) Senior Research Fellow ( 1156095 ) and supported by the Leukemia and Lymphoma Society SCOR grant 7015-18 . K.E.L was supported by NHMRC project grants ( 1145788 , 1162765 ) and ideas grant ( 1181089 ), and is an Australian Research Council ( ARC ) Future Fellow ( FT19100266 ); JEV was supported by NHMRC project grants ( 1145788 and 1101405 ), an ideas grant ( 1183070 ), a fellowship ( 1141466 ) and an investigator grant ( 2008692 ); ALS was supported by NHMRC ideas grant ( 2002965 ); JMM was supported by an NHMRC grant ( 1172929 ).Pathogen recognition and TNF receptors signal via receptor interacting serine/threonine kinase-3 (RIPK3) to cause cell death, including MLKL-mediated necroptosis and caspase-8-dependent apoptosis. However, the post-translational control of RIPK3 is not fully understood. Using mass-spectrometry, we identified that RIPK3 is ubiquitylated on K469. The expression of mutant RIPK3 K469R demonstrated that RIPK3 ubiquitylation can limit both RIPK3-mediated apoptosis and necroptosis. The enhanced cell death of overexpressed RIPK3 K469R and activated endogenous RIPK3 correlated with an overall increase in RIPK3 ubiquitylation. Ripk3K469R/K469R mice challenged with Salmonella displayed enhanced bacterial loads and reduced serum IFNγ. However, Ripk3K469R/K469R macrophages and dermal fibroblasts were not sensitized to RIPK3-mediated apoptotic or necroptotic signaling suggesting that, in these cells, there is functional redundancy with alternate RIPK3 ubiquitin-modified sites. Consistent with this idea, the mutation of other ubiquitylated RIPK3 residues also increased RIPK3 hyper-ubiquitylation and cell death. Therefore, the targeted ubiquitylation of RIPK3 may act as either a brake or accelerator of RIPK3-dependent killing.Peer reviewe
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