3,126 research outputs found

    Impact of chromophores on colour appearance in a computational skin model

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    Early diagnosis of skin cancer offers the patient more favorable treatment options. Color fidelity of skin images is a major concern for dermatologists as adoption of digital dermatoscopes is increasing rapidly. Accurate color depiction of the lesion and surrounding skin are vital in diagnostic evaluation of a lesion. We previously introduced VCT-Derma, a pipeline for dermatological Virtual Clinical Trials (VCTs) including detailed and flexible models of human skin and lesions, which represent the patient in the entire dermatoscopy-based diagnostic process. However, those initial models of skin and lesions did not properly account for tissue colors. Our new skin model accounts for tissue color appearance by incorporating chromophores (e.g., melanin, blood) into the tissue model, and simulating the optical properties of the various skin layers. The physical properties of the skin and lesion were selected from clinically plausible values. The model and simulated dermatoscope images were created in open modelling software, assuming a linear camera model. We have assumed ambient white lighting, with a 6mm distance to the camera. Our model of color appearance was characterised by comparing the brightness of the lesion to its depth. The brightness of the lesion is compared through the variability of the mean gray values of a cropped region around the lesion. We compare two skin models, one without extensive chromophore content and one with. Our preliminary evaluation of increasing chromophore content shows promise based on the results presented here. Further refinement and validation of the model is ongoing

    Playful Tarot: Adaptations of Tarot In, Through, and Across Games.

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    The magical practice of divination through tarot emanates from the sacred, ritualistic power of play. Long before tarot accretes esoteric symbolism as a divinatory tool, Italians played it as the parlour game tarrochi. Extending this history, many games implement tarot as a mechanical framework and a source of visual imagery. Yet, not all implementations of tarot are equally successful artistically and spiritually. Ludic tarot is often mechanistic (just another way to think about buffs and stats) or superficially thematic (visual imagery without underlying semiotic content). In this paper, we will unravel the intertwined history of games and tarot, exploring its relationship to other cartomantic practices, including the dark Gnostic “Game of Saturn” decoded by Peter Mark Adams in the Sola-Busca deck, the pragmatically cryptic Lenormand deck, and the divinatory use of standard 52-card playing decks in folk witchcraft. Building upon this historical insight, we will then analyse three related tabletop games as case studies: Chalice (in which tarot generates narratives of a failed Grail quest), Alas Vegas (which resolves conflict and generates narrative through tarot-driven blackjack), and Invisible Sun (which reinvents tarot through the circular Sooth deck driving its magic system). All three of these games weave resonant connections between the imagery and mechanics of cards and fictional gameworlds, thereby investing tarot with an eerie sense of meaningful coincidence or synchronicity. Understanding the techniques that create a more resonant experience of tarot can open the way for a deeper implementation of tarot in game development, as well as enable playful reflection and insight within the magical practice. Specifically, insights into non-digital ludic implementations of tarot can pave the way for richer and more resonant digital tarot applications, building upon and deepening the recent use of tarot in videogames (such as Tanya X. Short’s Cartomancy anthology and Adam Malone’s VR tarot)

    Wfs1 Is Expressed In Dopaminoceptive Regions Of The Amniote Brain And Modulates Levels Of D1-Like Receptors

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    During amniote evolution, the construction of the forebrain has diverged across different lineages, and accompanying the structural changes, functional diversification of the homologous brain regions has occurred. This can be assessed by studying the expression patterns of marker genes that are relevant in particular functional circuits. In all vertebrates, the dopaminergic system is responsible for the behavioral responses to environmental stimuli. Here we show that the brain regions that receive dopaminergic input through dopamine receptor D1 are relatively conserved, but with some important variations between three evolutionarily distant vertebrate lines–house mouse (Mus musculus), domestic chick (Gallus gallus domesticus) / common quail (Coturnix coturnix) and red-eared slider turtle (Trachemys scripta). Moreover, we find that in almost all instances, those brain regions expressing D1-like dopamine receptor genes also express Wfs1. Wfs1 has been studied primarily in the pancreas, where it regulates the endoplasmic reticulum (ER) stress response, cellular Ca2+ homeostasis, and insulin production and secretion. Using radioligand binding assays in wild type and Wfs1-/- mouse brains, we show that the number of binding sites of D1-like dopamine receptors is increased in the hippocampus of the mutant mice. We propose that the functional link between Wfs1 and D1-like dopamine receptors is evolutionarily conserved and plays an important role in adjusting behavioral reactions to environmental stimuli

    Synchrotron Emission from Hot Accretion Flows and the Cosmic Microwave Background Anisotropy

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    Current estimates of number counts of radio sources in the frequency range where the most sensitive Cosmic Microwave Background (CMB) experiments are carried out significantly under-represent sources with strongly inverted spectra. Hot accretion flows around supermassive black holes in the nuclei of nearby galaxies are expected to produce inverted radio spectra by thermal synchrotron emission. We calculate the temperature fluctuations and power spectra of these sources in the Planck Surveyor 30 GHz energy channel, where their emission is expected to peak. We find that their potential contribution is generally comparable to the instrumental noise, and approaches the CMB anisotropy level at small angular scales. Forthcoming CMB missions, which will provide a large statistical sample of inverted-spectra sources, will be crucial for determining the distribution of hot accretion flows in nearby quiescent galactic nuclei. Detection of these sources in different frequency channels will help constrain their spectral characteristics, hence their physical properties.Comment: 10 pages, 4 figures, accepted for publication in Ap

    Relativistic quantum measurement

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    Does the measurement of a quantum system necessarily break Lorentz invariance? We present a simple model of a detector that measures the spacetime localization of a relativistic particle in a Lorentz invariant manner. The detector does not select a preferred Lorentz frame as a Newton-Wigner measurement would do. The result indicates that there exists a Lorentz invariant notion of quantum measurement and sheds light on the issue of the localization of a relativistic particle. The framework considered is that of single-particle mechanics as opposed to field theory. The result may be taken as support for the interpretation postulate of the spacetime-states formulation of single-particle quantum theory.Comment: 9 pages, no figures: Revision: references adde

    In Vivo Systems Analysis Identifies Spatial and Temporal Aspects of the Modulation of TNF-α-Induced Apoptosis and Proliferation by MAPKs

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    Cellular responses to external stimuli depend on dynamic features of multipathway network signaling; thus, cell behavior is influenced in a complex manner by the environment and by intrinsic properties. Methods of multivariate systems analysis have provided an understanding of these convoluted effects, but only for relatively simplified examples in vitro. To determine whether such approaches could be successfully used in vivo, we analyzed the signaling network that determines the response of intestinal epithelial cells to tumor necrosis factor–α (TNF-α). We built data-driven, partial least-squares discriminant analysis (PLSDA) models based on signaling, apoptotic, and proliferative responses in the mouse small intestinal epithelium after systemic exposure to TNF-α. The extracellular signal–regulated kinase (ERK) signaling axis was a critical modulator of the temporal variation in apoptosis at different doses of TNF-α and of the spatial variation in proliferation in distinct intestinal regions. Inhibition of MEK, a mitogen-activated protein kinase kinase upstream of ERK, altered the signaling network and changed the temporal and spatial phenotypes consistent with model predictions. Our results demonstrate the dynamic, adaptive nature of in vivo signaling networks and identify natural, tissue-level variation in responses that can be deconvoluted only with quantitative, multivariate computational modeling. This study lays a foundation for the use of systems-based approaches to understand how dysregulation of the cellular network state underlies complex diseases.National Institute of General Medical Sciences (U.S.) (Grant R01-GM088827)National Cancer Institute (U.S.) (Grant U54-CA112967

    Quasi-One-Dimensional Spin Dynamics in dd-Electron Heavy-Fermion Metal Y1−x_{1-x}Scx_xMn2_2

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    Slow spin fluctuations (Îœ<1012\nu < 10^{12} s−1^-1) observed by the muon spin relaxation technique in Y1−x_{1-x}Scx_xMn2_2 exhibits a power law dependence on temperature (Μ∝Tα\nu \propto T^\alpha), where the power converges asymptotically to unity (α→1\alpha\rightarrow 1) as the system moves away from spin-glass instability with increasing Sc content xx. This linear TT dependence, which is common to that observed in LiV2_2O4_4, is in line with the prediction of the "intersecting Hubbard chains" model for a metallic pyrochlore lattice, suggesting that the geometrical constraints to t2g bands specific to the pyrochlore structure serve as a basis of the dd-electron heavy-fermion state.Comment: 5 pages, 4 figures, to appear in J. Phys. Soc. Jp
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