1,394 research outputs found

    A hydrophobic platform as a mechanistically relevant transition state stabilising factor appears to be present in the active centre of all glycoside hydrolases

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    AbstractAn in silico survey of the −1 subsite of all known 3D-structures of O-glycoside hydrolases containing a suitably positioned ligand has led to the recognition – apparently without exceptions – of a transition state stabilising hydrophobic platform which is complementary to a crucial hydrophobic patch of the ligand. This platform is family-specific and highly conserved. A comprehensive list is given with examples of enzymes belonging to 33 different families. Several typical constellations of platform – protein residues are described

    The Development of Working Memory: Exploring the Complementarity of Two Models

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    Author version made available in accordance with the publisher's policy for non-mandated open access submission. Under Elsevier's copyright, non-mandated authors are permitted to make work available in an institutional repository.The aim of the paper was to further explore the complementarity of the working memory models postulated by Pascual-Leone and Baddeley. Five-, six-, eight- and nine-year-old children were assessed on two working memory tasks, which have frequently been used within the respective streams of research: the Mr. Peanut task and the Corsi blocks task. Results indicated a developmental increase in spatial short-term memory for both tasks. Concurrent spatial suppression reduced performance on the two tasks in all four age groups. By contrast, articulatory suppression only interfered with recall on the Mr. Peanut task, and only in the older children. The two models were shown to make their own specific contribution to the interpretation of the data, attesting to their complementarity. Pascual-Leone’s theory offered a clear explanation of the results concerning the central aspects of working memory, i.e. the stepwise age-related increase in performance, whereas Baddeley’s model provided a convincing account of the findings regarding the peripheral phonological and visuo-spatial components, i.e. the effects of articulatory and spatial suppression. Key Words: short-term memory; spatial memory; information processing capacity; memory development; working memory models; rehearsal strategies; cognitive development

    Improving the Generalizability of Depression Detection by Leveraging Clinical Questionnaires

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    Automated methods have been widely used to identify and analyze mental health conditions (e.g., depression) from various sources of information, including social media. Yet, deployment of such models in real-world healthcare applications faces challenges including poor out-of-domain generalization and lack of trust in black box models. In this work, we propose approaches for depression detection that are constrained to different degrees by the presence of symptoms described in PHQ9, a questionnaire used by clinicians in the depression screening process. In dataset-transfer experiments on three social media datasets, we find that grounding the model in PHQ9's symptoms substantially improves its ability to generalize to out-of-distribution data compared to a standard BERT-based approach. Furthermore, this approach can still perform competitively on in-domain data. These results and our qualitative analyses suggest that grounding model predictions in clinically-relevant symptoms can improve generalizability while producing a model that is easier to inspect

    Improving the Generalizability of Depression Detection by Leveraging Clinical Questionnaires

    Get PDF
    Automated methods have been widely used to identify and analyze mental healthconditions (e.g., depression) from various sources of information, includingsocial media. Yet, deployment of such models in real-world healthcareapplications faces challenges including poor out-of-domain generalization andlack of trust in black box models. In this work, we propose approaches fordepression detection that are constrained to different degrees by the presenceof symptoms described in PHQ9, a questionnaire used by clinicians in thedepression screening process. In dataset-transfer experiments on three socialmedia datasets, we find that grounding the model in PHQ9's symptomssubstantially improves its ability to generalize to out-of-distribution datacompared to a standard BERT-based approach. Furthermore, this approach canstill perform competitively on in-domain data. These results and ourqualitative analyses suggest that grounding model predictions inclinically-relevant symptoms can improve generalizability while producing amodel that is easier to inspect.<br

    Clinical and Experimental Applications of NIR-LED Photobiomodulation

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    This review presents current research on the use of far-red to near-infrared (NIR) light treatment in various in vitro and in vivo models. Low-intensity light therapy, commonly referred to as “photobiomodulation,” uses light in the far-red to near-infrared region of the spectrum (630–1000 nm) and modulates numerous cellular functions. Positive effects of NIR–light-emitting diode (LED) light treatment include acceleration of wound healing, improved recovery from ischemic injury of the heart, and attenuated degeneration of injured optic nerves by improving mitochondrial energy metabolism and production. Various in vitro and in vivo models of mitochondrial dysfunction were treated with a variety of wavelengths of NIR-LED light. These studies were performed to determine the effect of NIR-LED light treatment on physiologic and pathologic processes. NIRLED light treatment stimulates the photoacceptor cytochrome c oxidase, resulting in increased energy metabolism and production. NIR-LED light treatment accelerates wound healing in ischemic rat and murine diabetic wound healing models, attenuates the retinotoxic effects of methanol-derived formic acid in rat models, and attenuates the developmental toxicity of dioxin in chicken embryos. Furthermore, NIR-LED light treatment prevents the development of oral mucositis in pediatric bone marrow transplant patients. The experimental results demonstrate that NIR-LED light treatment stimulates mitochondrial oxidative metabolism in vitro, and accelerates cell and tissue repair in vivo. NIR-LED light represents a novel, noninvasive, therapeutic intervention for the treatment of numerous diseases linked to mitochondrial dysfunction

    Periodic mass loss episodes due to an oscillation mode with variable amplitude in the hot supergiant HD50064

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    We aim to interpret the photometric and spectroscopic variability of the luminous blue variable supergiant HD\,50064 (V=8.21V=8.21).CoRoT space photometry and follow-up high-resolution spectroscopy, with a time base of 137\,d and 169\,d, respectively, was gathered, analysed and interpreted using standard time series analysis and light curve modelling methods as well as spectral line diagnostics.The space photometry reveals one period of 37\,d, which undergoes a sudden amplitude change with a factor 1.6. The pulsation period is confirmed in the spectroscopy, which additionally reveals metal line radial velocity values differing by 30\sim 30\,km\,s1^{-1} depending on the spectral line and on the epoch. We estimate \teff\sim13\,500\,K, \logg\sim1.5 from the equivalent width of Si lines. The Balmer lines reveal that the star undergoes episodes of changing mass loss on a time scale similar to the changes in the photometric and spectroscopic variability, with an average value of logM˙5\log\dot{\rm M}\simeq-5 (in M_\odot\,yr1^{-1}). We tentatively interpret the 37\,d period as due to a strange mode oscillation.Comment: 4 pages, accepted for publication in Astronomy & Astrophysics Letter
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