487 research outputs found

    The Role of Solar Wind Hydrogen in Space Weathering: Insights from Laboratory-Irradiated Northwest Africa 12008

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    Micrometeoroid impacts, solar wind plasma interactions, and regolith gardening drive the complicated and nuanced mechanism of space weathering (or optical maturation); a process by which a materials optical properties are changed as a result of chemical and physical alterations at the surface of grains on airless bodies. Reddened slopes, attenuated absorption bands, and an overall reduction in albedo in the visible and near-IR wavelength ranges are primarily the result of native iron nanoparticle (npFe0) production within glassy rims that form from sputtering and vaporization. The sizes and abundance of these particles provide information about the relative surface exposure age of a particular grain. In addition, many studies have indicated that composition greatly affects the rate at which optical maturation occurs. Despite our understanding of how npFe0 affects optical signatures, the relative roles of micrometeoroid bombardment and solar wind interactions remains undetermined. To simulate the early effects of weathering by the solar wind and to determine thresholds for optical change with respect to a given mineral phase, we irradiated a fine-grained lunar basalt with 1 keV H+ to a fluence of 6.4 x 1016 H+ per sq.cm. Surface alterations within four phases have been evaluated using transmission electron microscopy (TEM). We found that for a given fluence of H+, the extent of damage acquired by each grain was dependent on its composition. No npFe(0) was produced in any of the phases evaluated in this study. These results are consistent with many previous studies conducted using ions of similar energy, but they also provide valuable information about the onset of space weathering and the role of the solar wind during the early stages of optical maturation

    Considering the role of cognitive control in expert performance

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    © 2014, Springer Science+Business Media Dordrecht. Dreyfus and Dreyfus’ (1986) influential phenomenological analysis of skill acquisition proposes that expert performance is guided by non-cognitive responses which are fast, effortless and apparently intuitive in nature. Although this model has been criticised (e.g., by Breivik Journal of Philosophy of Sport, 34, 116–134 2007, Journal of the Philosophy of Sport, 40, 85–106 2013; Eriksen 2010; Montero Inquiry:An interdisciplinary Journal of Philosophy, 53, 105–122 2010; Montero and Evans 2011) for over-emphasising the role that intuition plays in facilitating skilled performance, it does recognise that on occasions (e.g., when performance goes awry for some reason) a form of ‘detached deliberative rationality’ may be used by experts to improve their performance. However, Dreyfus and Dreyfus (1986) see no role for calculative problem solving or deliberation (i.e., drawing on rules or mental representations) when performance is going well. In the current paper, we draw on empirical evidence, insights from athletes, and phenomenological description to argue that ‘continuous improvement’ (i.e., the phenomenon whereby certain skilled performers appear to be capable of increasing their proficiency even though they are already experts; Toner and Moran 2014) among experts is mediated by cognitive (or executive) control in three distinct sporting situations (i.e., in training, during pre-performance routines, and while engaged in on-line skill execution). We conclude by arguing that Sutton et al. Journal of the British Society for Phenomenology, 42, 78–103 (2011) ‘applying intelligence to the reflexes’ (AIR) approach may help to elucidate the process by which expert performers achieve continuous improvement through analytical/mindful behaviour during training and competition

    ЩОДО ПРОБЛЕМИ ФОРМУВАННЯ КОМУНІКАТИВНОЇ КОМПЕТЕНТНОСТІ ПРИ ОПАНУВАННІ ПСИХОЛОГІЧНИХ ЗНАНЬ СТУДЕНТАМИ-МЕДИКАМИ

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    The article deals with the possibility of forming of skills of communicative competence of medical students when using social-psychological training in the classroom as a part of the psychological circle. The necessity of improving of communicative competence of students of medical specialties is substantiated. We used art therapy techniques, role-playing games, reflexive techniques that enhance the experience of recognition units / feelings / patterns in relationships with people. Results of changes in communication of students that participate in an appropriate form of psychological work are summed.У статті розглядаються можливості формування навичок комунікативної компетентності студентів-медиків при використанні методу соціально-психологічного тренінгу в навчальному процесі в рамках психологічного гуртка. Обґрунтовано необхідність підвищення комунікативної компетентності у студентів медичних спеціальностей. Використовувалися методи арттерапії, рольових ігор, рефлексивних технік, що розширюють досвід розпізнавання установок/почуттів/патернів у відносинах з людьми. Підсумовані результати змін у спілкуванні студентів, які беруть участь у відповідній формі психологічної роботи.

    Tankyrase inhibition sensitizes cells to CDK4 blockade

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    Tankyrase (TNKS) 1/2 are positive regulators of WNT signaling by controlling the activity of the ss-catenin destruction complex. TNKS inhibitors provide an opportunity to suppress hyperactive WNT signaling in tumors, however, they have shown limited anti-proliferative activity as a monotherapy in human cancer cell lines. Here we perform a kinome-focused CRISPR screen to identify potential effective drug combinations with TNKS inhibition. We show that the loss of CDK4, but not CDK6, synergizes with TNKS1/2 blockade to drive G1 cell cycle arrest and senescence. Through precise modelling of cancer-associated mutations using cytidine base editors, we show that this therapeutic approach is absolutely dependent on suppression of canonical WNT signaling by TNKS inhibitors and is effective in cells from multiple epithelial cancer types. Together, our results suggest that combined WNT and CDK4 inhibition might provide a potential therapeutic strategy for difficult-to-treat epithelial tumors

    Screening by symmetry of long-range hydrodynamic interactions of polymers confined in sheets

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    Hydrodynamic forces may significantly affect the motion of polymers. In sheet-like cavities, such as the cell's cytoplasm and microfluidic channels, the hydrodynamic forces are long-range. It is therefore expected that that hydrodynamic interactions will dominate the motion of polymers in sheets and will be manifested by Zimm-like scaling. Quite the opposite, we note here that although the hydrodynamic forces are long-range their overall effect on the motion of polymers vanishes due to the symmetry of the two-dimensional flow. As a result, the predicted scaling of experimental observables such as the diffusion coefficient or the rotational diffusion time is Rouse-like, in accord with recent experiments. The effective screening validates the use of the non-interacting blobs picture for polymers confined in a sheet.Comment: http://www.weizmann.ac.il/complex/tlusty/papers/Macromolecules2006.pdf http://pubs.acs.org/doi/abs/10.1021/ma060251

    Haplós: Vibrotactile somaesthetic technology for body awareness

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    Inspired by somatic methodologies and neurophysiology, Haplós is a low-cost, wearable technology that applies vibrotactile patterns to the skin, can be incorporated in existing clothing and implements, and can be programmed and activated remotely. We review existing vibrotactile technologies and known uses of vibrotactile stimuli; describe the hardware, textile, and software components of Haplós; describe results from a quasi-experimental workshop to evaluate Haplós; and discuss future research and development directions

    Empathy, engagement, entrainment: the interaction dynamics of aesthetic experience

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    A recent version of the view that aesthetic experience is based in empathy as inner imitation explains aesthetic experience as the automatic simulation of actions, emotions, and bodily sensations depicted in an artwork by motor neurons in the brain. Criticizing the simulation theory for committing to an erroneous concept of empathy and failing to distinguish regular from aesthetic experiences of art, I advance an alternative, dynamic approach and claim that aesthetic experience is enacted and skillful, based in the recognition of others’ experiences as distinct from one’s own. In combining insights from mainly psychology, phenomenology, and cognitive science, the dynamic approach aims to explain the emergence of aesthetic experience in terms of the reciprocal interaction between viewer and artwork. I argue that aesthetic experience emerges by participatory sense-making and revolves around movement as a means for creating meaning. While entrainment merely plays a preparatory part in this, aesthetic engagement constitutes the phenomenological side of coupling to an artwork and provides the context for exploration, and eventually for moving, seeing, and feeling with art. I submit that aesthetic experience emerges from bodily and emotional engagement with works of art via the complementary processes of the perception–action and motion–emotion loops. The former involves the embodied visual exploration of an artwork in physical space, and progressively structures and organizes visual experience by way of perceptual feedback from body movements made in response to the artwork. The latter concerns the movement qualities and shapes of implicit and explicit bodily responses to an artwork that cue emotion and thereby modulate over-all affect and attitude. The two processes cause the viewer to bodily and emotionally move with and be moved by individual works of art, and consequently to recognize another psychological orientation than her own, which explains how art can cause feelings of insight or awe and disclose aspects of life that are unfamiliar or novel to the viewer

    Living on thin abstractions: more power/economic knowledge

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    Debates over the role of knowledge and know-how as key economic assets in the contemporary economy, although far from new, are now increasingly couched in terms of a new-found economic immateriality which allows for their costless reproduction and widespread geographical dissemination. In the rush to tie down and reproduce economic know-how in abstract codifiable form, it has become almost baffling to argue that our stock of economic knowledge may rest upon affects as much as analysis, expressive symbolism as much as abstract symbolism. This paper is an attempt to think through how such 'elusive' economic knowledges may be grasped, yet neither formalized nor codified in abstract terms. It is also a plea to consider the geography of economic knowledge outside of the tacit - explicit distinction
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