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Ancient alluvial plains at Oxia Planum, Mars
Get PDFThe geologic origin of the ancient, phyllosilicate-bearing bedrock at Oxia Planum, Mars, the ExoMars rover landing site, is unknown. The phyllosilicates record ancient aqueous processes, but the processes that formed the host bedrock remain elusive. Here, we use high-resolution orbital and topographic datasets from the HiRISE, CaSSIS and CTX instruments to investigate and characterize fluvial sinuous ridges (FSRs), found across the Oxia Planum region. The FSRs form segments up to 70 km long, are 20-600 m wide, and up to 9 m in height, with sub-horizontal layering common in ridge margins. Some FSRs comprise multi-story ridge systems; many are embedded within the phyllosilicate-bearing bedrock. We interpret the FSRs at Oxia Planum as deposits of ancient, episodically active, alluvial river systems (channel-belt and overbank deposits). Thus, at least some of the phyllosilicate-bearing bedrock was formed by ancient alluvial rivers, active across the wider region, though we do not exclude other processes from contributing to its formation as well. The presence of alluvial floodplains at Oxia Planum increases the chances of the ExoMars rover detecting signs of ancient life. Future exploration by the ExoMars rover can verify the alluvial interpretation and provides an opportunity to investigate some of the oldest river deposits in the Solar System
Psychotic experiences and negative symptoms from adolescence to emerging adulthood: developmental trajectories and associations with polygenic scores and childhood characteristics
Get PDFBackground. Psychotic experiences and negative symptoms (PENS) are common in nonclinical populations. PENS are associated with adverse outcomes, particularly when they
persist. Little is known about the trajectories of PENS dimensions in young people, nor
about the precursory factors associated with these trajectories.
Methods. We conducted growth mixture modelling of paranoia, hallucinations, and negative
symptoms across ages 16, 17, and 22 in a community sample (N = 12 049–12 652). We then
described the emergent trajectory classes through their associations with genome-wide polygenic scores (GPS) for psychiatric and educational phenotypes, and earlier childhood
characteristics.
Results. Three trajectory classes emerged for paranoia, two for hallucinations, and two for
negative symptoms. Across PENS, GPS for clinical help-seeking, major depressive disorder,
and attention deficit hyperactivity disorder were associated with increased odds of being in
the most elevated trajectory class (OR 1.07–1.23). Lower education GPS was associated
with the most elevated trajectory class for hallucinations and negative symptoms (OR 0.77–
0.91). Conversely for paranoia, higher education GPS was associated with the most elevated
trajectory class (OR 1.25). Trajectory class associations were not significant for schizophrenia,
obsessive-compulsive disorder, bipolar disorder, or anorexia GPS. Emotional/behaviour problems and life events in childhood were associated with increased odds of being in the most
elevated trajectory class across PENS.
Conclusions. Our results suggest latent heterogeneity in the development of paranoia, hallucinations, and negative symptoms in young people that is associated with specific polygenic
scores and childhood characteristics
"Bad Philosophy" or "Derivative Philosophy": labels that keep women out of the canon
Get PDFEfforts to include women in the canon have long been beset by reactionary gatekeeping, typified by the charge, 'That's Not Philosophy'. That charge does not apply to early-to-mid-analytic female philosophers – Welby, Ladd-Franklin, Bryant, Jones, de Laguna, Stebbing, Ambrose, Macdonald – with job titles like 'Lecturer in Logic' or 'Professor of Philosophy', and publications in Mind, Journal of Philosophy, and Proceedings of the Aristotelian Society. It is hopeless to dismiss their work as 'Not Philosophy'. Then why aren't they in the canon of analytic philosophy? Comparable reactionary gatekeeping affects them, we argue, but typified by the labels 'Bad Philosophy' or 'Derivative Philosophy'. Virtue and vice epistemology help explain both why these women were neglected and why their own approaches are often epistemically virtuous. Both their contemporaries and historians are deficient in scholarly virtues in labelling these women's work 'bad', or derived from male mentors or partners, with no or specious justification. Their disparaged qualities - intellectual humility, modesty, critical self-reflection, crediting others, disclosing biases - are frequently outright epistemic virtues
Generalised Wendland functions for the sphere
Get PDFIn this paper we compute the spherical Fourier expansions coefficients for
the restriction of the generalised Wendland functions from dimensional Euclidean space to the dimensional unit sphere. We use results from the theory of special functions to show that they can be expressed in a closed form as a multiple of a certain hypergeometric function. We present tight asymptotic bounds on the decay rate of the spherical Fourier coefficients and, in the case where is odd, we are able to provide the precise asymptotic rate of decay. Numerical evidence suggests that this precise asymptotic rate also holds when is even and we pose this as an open problem. Finally, we observe a close connection between the asymptotic decay rate of the spherical Fourier coefficients and that of the corresponding Euclidean Fourier transform
Dissonant waves: Ernst Schoen and experimental sound in the 20th Century
No full textBook synopsis: An investigation of the cultures and technologies of early radio and how a generation of cultural operators—with Schoen at the center—addressed crisis and adversity.
Dials, knobs, microphones, clocks; heads, hands, breath, voices. Ernst Schoen joined Frankfurt Radio in the 1920s as programmer and accelerated the potentials of this collision of bodies and technologies. As with others of his generation, Schoen experienced crisis after crisis, from the violence of war, the suicide of friends, economic collapse, and a brief episode of permitted experimentalism under the Weimar Republic, for those who would foster aesthetic, technical, and political revolution. The counterreaction was Nazism—and Schoen and his milieux fell victim to it, found ways out of it, or hit against it with all their might.
Dissonant Waves tracks the life of Ernst Schoen—poet, composer, radio programmer, theorist, and best friend of Walter Benjamin from childhood—as he moves between Frankfurt, Berlin, Paris, and London. It casts radio history and practice into concrete spaces, into networks of friends and institutions, into political exigencies and domestic plights, and into broader aesthetic discussions of the politicization of art and the aestheticization of politics. Through friendship and comradeship, a position in state-backed radio, imprisonment, exile, networking in a new country, re-emigration, ill-treatment, neglect, Schoen suffers the century and articulates its broken promises.
An exploration of the ripples of radio waves, the circuits of experimentation and friendship and the proposals that half-found a route into the world, and might yet spark political-technical experimentation
Control of atypical PKCι membrane dissociation by tyrosine phosphorylation within a PB1-C1 interdomain interface
Get PDFAtypical PKCs are cell polarity kinases that operate at the plasma membrane where they function within multiple molecular complexes to contribute to the establishment and maintenance of polarity. In contrast to the classical and novel PKCs, atypical PKCs do not respond to diacylglycerol cues to bind the membrane compartment. Until recently it was not clear how aPKCs are recruited; whether aPKCs can directly interact with membranes or whether they are dependent on other protein interactors to do so. Two recent studies identified the pseudo-substrate region and the C1 domain as direct membrane interaction modules, however their relative importance and coupling are unknown. We combined molecular modelling and functional assays to show that the regulatory module of aPKCι, comprising the PB1 pseudo-substrate and C1 domains, forms a cooperative and spatially continuous invariant membrane interaction platform. Furthermore, we show the coordinated orientation of membrane-binding elements within the regulatory module requires a key PB1-C1 interfacial β-strand (BSL). We show this element contains a highly conserved Tyr residue that can be phosphorylated and that negatively regulates the integrity of the regulatory module, leading to membrane release. We thus expose a novel regulatory mechanism of aPKCι membrane binding and release during cell polarization
Structural journey of an insecticidal protein against western corn rootworm
Get PDFThe broad adoption of transgenic crops has revolutionized agriculture. However, resistance to insecticidal proteins by agricultural pests poses a continuous challenge to maintaining crop productivity and new proteins are urgently needed to replace those utilized for existing transgenic traits. We identified an insecticidal membrane attack complex/perforin (MACPF) protein, Mpf2Ba1, with strong activity against the devastating coleopteran pest western corn rootworm (WCR) and a novel site of action. Using an integrative structural biology approach, we determined monomeric, pre-pore and pore structures, revealing changes between structural states at high resolution. We discovered an assembly inhibition mechanism, a molecular switch that activates pre-pore oligomerization upon gut fluid incubation and solved the highest resolution MACPF pore structure to-date. Our findings demonstrate not only the utility of Mpf2Ba1 in the development of biotechnology solutions for protecting maize from WCR to promote food security, but also uncover previously unknown mechanistic principles of bacterial MACPF assembly
Black shales and mesozonal quartz vein-hosted Au: The Truchas Syncline, Spain and the Harlech Dome, Wales, a comparative study
No full textA comparative study of quartz vein-hosted gold occurrences associated with Palaeozoic metapelites in two areas of Wales and Spain combines new, previously unpublished and published data. Metamorphic grade is greenschist in both areas, but very low-grade indicators in the host metapelites distance the environment from the greenschist/amphibolite transition zone required for some orogenic gold occurrences. Basin fertility for Au is indicated by the presence of auriferous pyrites in the protolith black shales in Spain. Only minor igneous activity has taken place in both study areas. Mineral parageneses are similar, with early sulphide phases characterized by As/Co and later auriferous phases by Cu/Pb/Zn sulphides. Mesozonal P-T conditions apply at deposition in both terranes. In Spain, mineralisation typically occurs in quartzites near to the metapelites, but not where the veins are in contact with them, and extensional faulting appears to be a stronger control over mineralisation than geochemical interaction with metapelite wall-rocks. In Wales, both structural and geochemical factors (C content of the wall-rocks and coupled oxidation of NH4 ions substituted in wall-rock phyllosilicates to produce (CH4 and N2) could have a role in Au deposition. In both areas, minor cross-fault systems between larger faults are typical hosts of the mineralisation. Assignment is made to different subtypes of the orogenic gold model but these subtypes share the characteristic of a local source. This has implications for exploration methodology in epizonal/anchizonal metapelite-dominated terranes, where indicators of basin fertility for Au within the protolith itself assume importance
What makes theme park experience less enjoyable? Evidence from online customer reviews of Disneyland China
Get PDFThis study aims to explore the causes of tourists’ less enjoyment in theme parks through an unsupervised machine learning approach – Structural Topic Modelling. Specifically, the research extracted a comprehensive list of discussion topics about their travel experience through the analysis of 112,000 customer reviews released by tourists from Shanghai Disney Resort from June 16, 2016 to March 4, 2022. Then, we use sentiment analysis to distinguish positive and negative topics, and explore the relationship between tourists who buy different ticket types and sentiment in negative topics. The results show that problems such as "parking", "service attitude", "recommendation feeling", "experience comparison" and "entrance" may be the main reasons for unpleasant experience. In addition, we also found that when tourists travel in groups (such as family tickets), customers feel unhappy because of parking problems and fast track problems. And when tourists travel alone or with small groups, staff's service attitude, experience comparison and entrance process are more concerned. Our findings can help theme park managers better understand the expectations of tourists, take effective measures to tackle issues causing customer dissatisfaction, and contribute to the theme park studies in tourism management
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