1,317 research outputs found
A Psychophysical Experiment Regarding Components of the Plausibility Illusion
We report on the design and results of an experiment investigating factors influencing Slater’s Plausibility Illusion (Psi) in
virtual environments. Slater proposed Psi and Place Illusion (PI) as orthogonal components of virtual experience which contribute
to realistic response in a VE. PI corresponds to the traditional conception of presence as “being there,” so there exists a substantial
body of previous research relating to PI, but very little relating to Psi. We developed this experiment to investigate the components
of plausibility illusion using subjective matching techniques similar to those used in color science. Twenty-one participants each
experienced a scenario with the highest level of coherence (the extent to which a scenario matches user expectations and is internally
consistent), then in eight different trials chose transitions from lower-coherence to higher-coherence scenarios with the goal of matching
the level of Psi they felt in the highest-coherence scenario. At each transition, participants could change one of the following coherence
characteristics: the behavior of the other virtual humans in the environment, the behavior of their own body, the physical behavior
of objects, or the appearance of the environment. Participants tended to choose improvements to the virtual body before any other
improvements. This indicates that having an accurate and well-behaved representation of oneself in the virtual environment is the
most importa
Оборудование для испытания листовых конструкционных материалов при двухосном растяжении. Сообщение 1. Испытания односторонним давлением рабочей среды
Рассмотрены конструктивные особенности оборудования для исследования прочности и
закономерностей разрушения листовых конструкционных материалов при двухосном растяжении
путем нагружения образцов односторонним давлением рабочей среды.
Предложены решения ряда проблем методического характера, связанных с испытаниями
при высоких уровнях давления рабочей среды, что позволяет обеспечить необходимые
режимы охлаждения образцов, снизить уровень энергии разрушения, повысить надежность
и безопасность испытаний.Розглянуто конструктивні особливості устаткування для дослідження міцності
і закономірностей руйнування листових конструкційних матеріалів
при двовісному розтязі зразків одностороннім тиском робочого середовища.
Запропоновано рішення ряду проблем методичного характеру, що пов’язані
з випробуваннями при високих рівнях тиску робочого середовища. Це
дозволить забезпечити необхідні режими охолодження зразків, знизити рівень
енергії руйнування, підвищити надійность та безпеку випробувань.Design features of the equipment for studying
strength and regularities of fracture of sheet
structural materials in biaxial tension by subjecting
specimens to one-sided pressure of a working
medium are considered.
Solutions were suggested for a number of
methodological problems related to testing at
high levels of pressure of a working medium.
These solutions make it possible to provide necessary
conditions of cooling of specimens,
lower the level of fracture energy, and improve
reliability and safety of the tests
Population genetics in compressible flows
We study competition between two biological species advected by a
compressible velocity field. Individuals are treated as discrete Lagrangian
particles that reproduce or die in a density-dependent fashion. In the absence
of a velocity field and fitness advantage, number fluctuations lead to a
coarsening dynamics typical of the stochastic Fisher equation. We then study
three examples of compressible advecting fields: a shell model of turbulence, a
sinusoidal velocity field and a linear velocity sink. In all cases, advection
leads to a striking drop in the fixation time, as well as a large reduction in
the global carrying capacity. Despite localization on convergence zones, one
species goes extinct much more rapidly than in well-mixed populations. For a
weak harmonic potential, one finds a bimodal distribution of fixation times.
The long-lived states in this case are demixed configurations with a single
boundary, whose location depends on the fitness advantage.Comment: 10 pages, 5 figures, submitte
A new cell primo-culture method for freshwater benthic diatom communities
A new cell primo-culture method was developed for the benthic diatom community isolated from biofilm sampled in rivers. The approach comprised three steps: (1) scraping biofilm from river pebbles, (2) diatom isolation
from biofilm, and (3) diatom community culture. With a view to designing a method able to stimulate the growth of diatoms, to limit the development of other microorganisms, and to maintain in culture a community similar to the original natural one, different factors were tested in step 3:
cell culture medium (Chu No 10 vs Freshwater “WC” medium modified), cell culture vessel, and time of culture. The results showed that using Chu No 10 medium in an Erlenmeyer flask for cell culture was the optimal method,
producing enough biomass for ecotoxicological tests as well as minimising development of other microorganisms. After 96 h of culture, communities differed from the original communities sampled in the two rivers studied.
Species tolerant of eutrophic or saprobic conditions were favoured during culture. This method of diatom community culture affords the opportunity to assess, in vitro, the effects of different chemicals or effluents (water samples andindustrial effluents) on diatom communities, as well as on diatom cells, from a wide range of perspectives
Urocortin, a CRF-like peptide, restores key indicators of damage in the substantia nigra in a neuroinflammatory model of Parkinson's disease
We have recently observed that the corticotrophin releasing hormone (CRF) related peptide urocortin (UCN) reverses key features of nigrostriatal damage in the hemiparkinsonian 6-hydroxydopamine lesioned rat. Here we have studied whether similar effects are also evident in the lipopolysaccaride (LPS) neuroinflammatory paradigm of Parkinson's disease (PD). To do this we have measured restoration of normal motor behaviour, retention of nigral dopamine (DA) and also tyrosine hydroxylase (TH) activity. Fourteen days following intranigral injections of LPS and UCN, rats showed only modest circling after DA receptor stimulation with apomorphine, in contrast to those given LPS and vehicle where circling was pronounced. In separate experiments, rats received UCN seven days following LPS, and here apomorphine challenge caused near identical circling intensity to those that received LPS and UCN concomitantly. In a similar and consistent manner with the preservation of motor function, UCN 'protected' the nigra from both DA depletion and loss of TH activity, indicating preservation of DA cells. The effects of UCN were antagonised by the non-selective CRF receptor antagonist α-helical CRF and were not replicated by the selective CRF2 ligand UCN III. This suggests that UCN is acting via CRF1 receptors, which have been shown to be anti-inflammatory in the periphery. Our data therefore indicate that UCN is capable of maintaining adequate nigrostriatal function in vivo, via CRF1 receptors following a neuro-inflammatory challenge. This has potential therapeutic implications in PD
Glucagon-like peptide 1 receptor stimulation reverses key deficits in distinct rodent models of Parkinson's disease
<p>Abstract</p> <p>Background</p> <p>It has recently become apparent that neuroinflammation may play a significant role in Parkinson's disease (PD). This is also the case in animal paradigms of the disease. The potential neuroprotective action of the glucagon-like peptide 1 receptor (GLP-1R) agonist exendin-4 (EX-4), which is protective against cytokine mediated apoptosis and may stimulate neurogenesis, was investigated In paradigms of PD.</p> <p>Methods</p> <p>Two rodent 'models' of PD, 6-hydroxydopamine (6-OHDA) and lipopolysaccaride (LPS), were used to test the effects of EX-4. Rats were then investigated <it>in vivo </it>and <it>ex vivo </it>with a wide range of behavioural, neurochemical and histological tests to measure integrity of the nigrostriatal system.</p> <p>Results</p> <p>EX-4 (0.1 and 0.5 μg/kg) was given seven days after intracerebral toxin injection. Seven days later circling behaviour was measured following apomorphine challenge. Circling was significantly lower in rats given EX-4 at both doses compared to animals given 6-OHDA/LPS and vehicle. Consistent with these observations, striatal tissue DA concentrations were markedly higher in 6-OHDA/LPS + EX-4 treated rats versus 6-OHDA/LPS + vehicle groups, whilst assay of L-DOPA production by tyrosine hydroxylase was greatly reduced in the striata of 6-OHDA/LPS + vehicle rats, but this was not the case in rats co-administered EX-4. Furthermore nigral TH staining recorded in 6-OHDA/LPS + vehicle treated animals was markedly lower than in sham-operated or EX-4 treated rats. Finally, EX-4 clearly reversed the loss of extracellular DA in the striata of toxin lesioned freely moving rats.</p> <p>Conclusion</p> <p>The apparent ability of EX-4 to arrest progression of, or even reverse nigral lesions once established, suggests that pharmacological manipulation of the GLP-1 receptor system could have substantial therapeutic utility in PD. Critically, in contrast to other peptide agents that have been demonstrated to possess neuroprotective properties in pre-clinical models of PD, EX-4 is in current clinical use in the management of type-II diabetes and freely crosses the blood brain barrier; hence, assessment of the clinical efficacy of EX-4 in patients with PD could be pursued without delay.</p
Проблемы увеличения продуктивности АПК в Украине и пути повышения его потенциала
Целью статьи является изучение причин снижения показателей продуктивности в агропромышленном комплексе и путей повышения продуктивности сельскохозяйственных культур
Aging Skin: Nourishing from Out-In. Lessons from Wound Healing
Skin lesion therapy, peculiarly in the elderly, cannot be isolated from understanding that the skin is an important organ consisting of different tissues. Furthermore, dermis health is fundamental for epidermis
integrity, and so adequate nourishment is mandatory in maintaining skin integrity. The dermis nourishes the epidermis, and a healthy epidermis protects the dermis from the environment, so nourishing the dermis
through the epidermal barrier is a technical problem yet to be resolved. This is also a consequence of the laws and regulations restricting cosmetics, which cannot have properties that pass the epidermal layer.
There is higher investment in cosmetics than in the pharmaceutical industry dealing with skin therapies, because the costs of drug registration are enormous and the field is unprofitable. Still, wound healing may
be seen as an opportunity to “feed” the dermis directly. It could also verify whether providing substrates could promote efficient healing and test optimal skin integrity maintenance, if not skin rejuvenation, in an
ever aging population
Mapping the UK thesis landscape: Phase 1 project report for Unlocking Thesis Data
This report details the work (April-July 2015) of Unlocking Thesis Data, where the project carried out a survey of EThOS institutions, interviewed staff at six universities for more in-depth case studies, and synthesised the findings. Overall, there is much appetite for applying DOIs to theses and their data (which includes datasets, software components and other non-textual supplementary files) and ORCiDs to research students. Glasgow, Southampton and East London universities each minted a DOI for an existing thesis, demonstrating the viability of our intent, but the case studies showed there are constraints in both processes and technologies to be addressed before persistent identifiers (PID) for theses can be a nationwide reality in the UK. The project makes five recommendations for further work in a second phase: 1. Hold at least three thesis “clinics” to investigate opportunities and barriers to assigning DOI and ORCiD identifiers in UK universities 2. Engage with system suppliers/vendors to identify opportunities for enhancing software with required PIDs 3. Consult with EThOS formally to understand what needs to change in EThOS systems and processes to harvest and display PIDs and related metadata for theses and their data 4. Evaluate approaches to updating UKETD profile, initially in EPrints, before planning software enhancements 5. Investigate requirements and solutions for those institutions that use EThOS as their first-point repository
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Remarks on the Concept of Critique in Habermasian Thought
The main purpose of this paper is to examine the concept of critique in Habermasian thought. Given that the concept of critique is a central theoretical category in the work of the Frankfurt School, it comes as a surprise that little in the way of a systematic account which sheds light on the multifaceted meanings of the concept of critique in Habermas’s oeuvre can be found in the literature. This paper aims to fill this gap by exploring the various meanings that Habermas attributes to the concept of critique in 10 key thematic areas of his writings: (1) the public sphere, (2) knowledge, (3) language, (4) morality, (5) ethics, (6) evolution, (7) legitimation, (8) democracy, (9) religion, and (10) modernity. On the basis of a detailed analysis of Habermas’s multifaceted concerns with the nature and function of critique, the study seeks to demonstrate that the concept of critique can be considered not only as a constitutive element but also as a normative cornerstone of Habermasian thought. The paper draws to a close by reflecting on some of the limitations of Habermas’s conception of critique, arguing that in order to be truly critical in the Habermasian sense we need to turn the subject of critique into an object of critique
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