2,620 research outputs found
Coopération homme-machine en conduite automobile assistée : Contrôle cognitif et contrôle de la trajectoire
This research relates to cooperatives activities between car drivers and driving assistances. The theoretical framework deals with cognitive processes implied in car driving. It also proposes a classification of various potential types of lateral control assistance devices according to their influence on human-machine cooperation. Three experimental studies are presented. The first two assessed the influence of lane departure warning systems on driving. Results point out that giving a subsymbolic motor cue on the steering wheel is more effective than a simple warning, which intervenes upstream in situation diagnosis. The third experiment concerned the influence of the delegation of lateral control on steering behaviour and visual exploration. Changes in visual strategies and difficulties to return to manual control when the device was invalid were observed.Ce travail de thèse porte sur les activités coopératives prenant place entre les conducteurs et les assistances à la conduite. Le cadre théorique traite des processus cognitifs impliqués dans la conduite. Il propose également une classification des différents types d'assistance au contrôle latéral envisageables en fonction des problématiques associées en termes de coopération homme-machine. Trois études expérimentales sont présentées. Les deux premières ont cherché à évaluer l'influence de l'introduction d'avertissements aux sorties de voie dans l'activité de conduite. Les résultats mettent en avant la plus grande efficacité d'un dispositif d'assistance fournissant un indice moteur (subsymbolique) sur le volant, en supplément à l'amélioration du diagnostic de la situation propre à l'avertissement. La troisième étude s'intéresse à l'impact de la délégation du contrôle latéral à un automate sur les comportements des conducteurs. Des modifications dans les prises d'informations visuelles, ainsi que des difficultés de reprise en main en situation d'invalidité du dispositif sont apparues
Parenting Young People with Complex Regional Pain Syndrome: An Analysis of the Process of Parental Online Communication
Introduction:
Parenting a young person with Complex Regional Pain Syndrome (CRPS) is associated with high levels of parental distress and numerous emotional, informational and practical challenges. To meet these challenges, parents seek others undergoing similar experiences, both in face-to-face and online forums.
Objectives:
The objective of this study was to conduct a qualitative analysis of online forum data to explore the process of parental forum communication regarding parenting a young person with CRPS in online spaces.
Methods:
A total of 107 forum posts relating to parenting a young person with CRPS were collected from 39 users across two public forums. Data was analyzed using Thematic Analysis.
Results:
Findings identified two themes: “The informal rules of exchanging and receiving network support” and “Parents positioning themselves as experts”. The first theme highlighted the varied nature of support sought and provided by parents in addition to social rules associated with the negotiation of this support. The second theme represented an understanding of how parents presented themselves as experts in their young person’s pain, both in relation to fellow parents and healthcare professionals.
Conclusions:
This study provided a novel insight into support and communicational exchanges between parents of young people with CRPS on online public forums. Findings identified the perceived usefulness of online spaces in terms of parents of young people with CRPS seeking and providing support. Further research can helpfully investigate how we might implement online peer mentoring to improve support further for parents
Uncertainty quantification of transition operators in the empirical shell model
While empirical shell model calculations have successfully described
low-lying nuclear data for decades, only recently has significant effort been
made to quantify the uncertainty in such calculations. Here we quantify the
statistical error in effective parameters for transition operators in empirical
calculations in the (--) valence space,
specifically the quenching of Gamow-Teller transitions, effective charges for
electric quadrupole (E2) transitions, and the effective orbital and spin
couplings for magnetic dipole (M1) transitions. We find the quenching factor
for Gamow-Teller transitions relative to free-space values is tightly
constrained and that the isoscalar coupling of E2 is much more tightly
constrained than the isovector coupling. For effective M1 couplings, we found
isovector components more constrained than isoscalar, but that to get any
sensible result we had to fix one of four couplings. This detailed
quantification of uncertainties, while highly empirical, nonetheless is an
important step towards interpretation of experiments
Dynamic scan paths investigations under manual and highly automated driving
Active visual scanning of the scene is a key task-element in all forms of human locomotion. In the field of driving, steering (lateral control) and speed adjustments (longitudinal control) models are largely based on drivers’ visual inputs. Despite knowledge gained on gaze behaviour behind the wheel, our understanding of the sequential aspects of the gaze strategies that actively sample that input remains restricted. Here, we apply scan path analysis to investigate sequences of visual scanning in manual and highly automated simulated driving. Five stereotypical visual sequences were identified under manual driving: forward polling (i.e. far road explorations), guidance, backwards polling (i.e. near road explorations), scenery and speed monitoring scan paths. Previously undocumented backwards polling scan paths were the most frequent. Under highly automated driving backwards polling scan paths relative frequency decreased, guidance scan paths relative frequency increased, and automation supervision specific scan paths appeared. The results shed new light on the gaze patterns engaged while driving. Methodological and empirical questions for future studies are discussed.Active visual scanning of the scene is a key task-element in all forms of human locomotion. In the field of driving, steering (lateral control) and speed adjustments (longitudinal control) models are largely based on drivers’ visual inputs. Despite knowledge gained on gaze behaviour behind the wheel, our understanding of the sequential aspects of the gaze strategies that actively sample that input remains restricted. Here, we apply scan path analysis to investigate sequences of visual scanning in manual and highly automated simulated driving. Five stereotypical visual sequences were identified under manual driving: forward polling (i.e. far road explorations), guidance, backwards polling (i.e. near road explorations), scenery and speed monitoring scan paths. Previously undocumented backwards polling scan paths were the most frequent. Under highly automated driving backwards polling scan paths relative frequency decreased, guidance scan paths relative frequency increased, and automation supervision specific scan paths appeared. The results shed new light on the gaze patterns engaged while driving. Methodological and empirical questions for future studies are discussed.Peer reviewe
Driver stress detection : identification of the physiological parameters depending on stress exposure
Driving is a complex activity taking place in a dynamic environment integrating risks and fatal
situations. Many stressors (e.g, complexity of the situation, imminent danger, short or long exposure)
may lead to stress states (e.g, anxiety, distress, fatigue). Stress states represent also a threat
for drivers as they may affect emotions and cognitive abilities. It results in inappropriate driving
behaviors, sometimes dangerous for the safety of the driver. This is precisely the close link between
driver stress and substantial risk of accidents that has pushed the players of road safety and
the automotive company to highlight the problem of driver stress. The challenge consists to improve
the detection, evaluation, and understanding of the driver stress to design new technologies
informing the driver of his stress condition or offering stress-reducing solutions adapted to the
driving situation
In-situ testing of innovative marine instrumentation for nutrients, heavy metals and pH in Kongsfjorden, Svalbard Islands
Marine ecosystems are integral part of fundamental environmental functions that support life on Earth like climate control, erosion prevention and absorption of carbon dioxide. Oceans contribute to economical activities too with the following prosperity, social welfare, and increase in life quality. Nevertheless, several marine environments also in the European framework show increasing challenges to tackle like the loss of biodiversity and habitats, pollution and impacts due to climate change. For Italy and for Europe a growing environmental interest and awareness in both the public and private sectors is combined with a common strategic goal to ensure sustainable development and the continuity of economic activities. In order to achieve this goal and to improve the competitiveness of Italy and the EU, new technologies and methods for monitoring the marine environment are required
Humans shape the year-round distribution and habitat use of an opportunistic scavenger
Research focused on evaluating how human food subsidies influence the foraging ecology of scavenger species is scarce but essential for elucidating their role in shaping behavioral patterns, population dynamics, and potential impacts on ecosystems. We evaluate the potential role of humans in shaping the year-round distribution and habitat use of individuals from a typical scavenger species, the yellow-legged gull (Larus michahellis), breeding at southwestern Spain. To do this, we combined long-term, nearly continuous GPS-tracking data with spatially explicit information on habitat types and distribution of human facilities, as proxied by satellite imagery of artificial night lights. Overall, individuals were mainly associated with freshwater habitats (mean proportion, 95% CI: 40.6%, 36.9%-44.4%) followed by the marine-related systems (40.3, 37.7%-42.8%), human-related habitats (13.5%, 13.2%-13.8%), and terrestrial systems (5.5%, 4.6%-6.5%). However, these relative contributions to the overall habitat usage largely changed throughout the annual cycle as a likely response to ecological/physiological constraints imposed by varying energy budgets and environmental constraints resulting from fluctuations in the availability of food resources. Moreover, the tight overlap between the year-round spatial distribution of gulls and that of human facilities suggested that the different resources individuals relied on were likely of anthropogenic origin. We therefore provide evidence supporting the high dependence of this species on human-related food resources throughout the annual cycle. Owing to the ability of individuals to disperse and reach transboundary areas of Spain, Portugal, or Morocco, international joint efforts aimed at restricting the availability of human food resources would be required to manage this overabundant species and the associated consequences for biodiversity conservation (e.g., competitive exclusion of co-occurring species) and human interests (e.g., airports or disease transmission)
Factores Asociados a Maloclusión en Estudiantes de Odontología de la Universidad Peruana Los Andes Huancayo
Objetivo: El propósito del presente estudio consistió en determinar los Factores asociados a maloclusión en estudiantes de Odontología de la Universidad Peruana los Andes – Huancayo 2015. Metodología: Se realizó un estudio descriptivo de corte transversal, con una muestra de 70 estudiantes (38 mujeres y 32 varones), entre 18 a 27 años de edad, quienes fueron seleccionados teniendo en cuenta los criterios de inclusión; así mismo los estudiantes tuvieron que rellenar un consentimiento informado para poder ingresar al estudio, luego de ello se utilizó una ficha de recolección de datos, se realizó un exámen clínico y se procedió a tomar sus respectivas impresiones a cada alumno para obtener sus modelos y realizar su posterior análisis. Se hizo uso de fotografías para identificar el ángulo del perfil, ángulo nasolabial, etc. El paquete estadístico que se empleó en la investigación fue el SPSS versión 22. La relación entre las variables se contrastó mediante la prueba de Chi2. Se determinó un nivel de 0.05. Resultados: El ángulo de perfil más frecuente fue el recto (54,3%), se presentaron más estudiantes con zonas de apiñamiento que con diastemas. En cuanto al tipo de maloclusión el 40 % presentó clase II división 1, 37% clase I y 22,9% clase III, la forma de arco que predominó en el maxilar superior e inferior fue la ovalada. De los 70 casos estudiados el 80% presentó el tercio facial inferior aumentado. Conclusiones: Sólo en el caso del ángulo de perfil se encontró relación estadísticamente significativa con la maloclusión clase II división 1(Chi2: 0.000).Tesi
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Myricetin, the main flavonoid in Syzygium cumini leaf, is a novel inhibitor of platelet thiol isomerases PDI and ERp5
Background: Flavonoids have been characterized as a prominent class of compounds to treat thrombotic diseases through the inhibition of thiol isomerases. Syzygium cumini is a flavonoid-rich medicinal plant that contains myricetin and gallic acid. Little is known about the potential anti-platelet properties of S. cumini and its constituent flavonoids.
Objective
To evaluate the anti-platelet effects and mechanism of action of a polyphenol-rich extract (PESc) from S. cumini leaf and its most prevalent polyphenols, myricetin and gallic acid.
Methods
PESc, myricetin and gallic acid were incubated with platelet-rich plasma and washed platelets to assess platelet aggregation and activation. In vitro platelet adhesion and thrombus formation as well as in vivo bleeding time were performed. Finally, myricetin was incubated with recombinant thiol isomerases to assess its potential to bind and inhibit these, whilst molecular docking studies predicted possible binding sites.
Results:
PESc decreased platelet activation and aggregation induced by different agonists. Myricetin exerted potent anti-platelet effects, whereas gallic acid did not. Myricetin reduced the ability of platelets to spread on collagen, form thrombi in vitro without affecting haemostasis in vivo. Fluorescence quenching studies suggested myricetin binds to different thiol isomerases with similar affinity, despite inhibiting only protein disulphide isomerase (PDI) and ERp5 reductase activities (IC50~3.5 μM). Finally, molecular docking studies suggested myricetin formed non-covalent bonds with PDI and ERp5.
Conclusions:
PESc and its most abundant flavonoid myricetin strongly inhibit platelet function. Additionally, myricetin is a novel inhibitor of ERp5 and PDI, unveiling a new therapeutic perspective for the treatment of thrombotic disorders
The Sizes and Luminosities of Massive Star Clusters
The masses of star clusters range over seven decades, from ten up to one
hundred million solar masses. Remarkably, clusters with masses in the range
10^4 to 10^6 solar mases show no systematic variation of radius with mass.
However, recent observations have shown that clusters with masses greater than
3x10^6 solar masses do show an increase in size with increasing mass. We point
out that clusters with m>10^6 solar masses were optically thick to far infrared
radiation when they formed, and explore the hypothesis that the size of
clusters with m> 3x10^6 solar masses is set by a balance between accretion
powered radiation pressure and gravity when the clusters formed, yielding a
mass-radius relation r~0.3(m/10^6M_\odot)^{3/5} pc. We show that the Jeans mass
in optically thick objects increases systematically with cluster mass. We
argue, by assuming that the break in the stellar initial mass function is set
by the Jeans mass, that optically thick clusters are born with top heavy
initial mass functions; it follows that they are over-luminous compared to
optically thin clusters when young, and have a higher mass to light ratio
Upsilon_V=m/L_V when older than ~1 Gyr. Old, optically thick clusters have
Upsilon_V~ mcl^{0.1-0.3}. It follows that L_V~\sigma^{\beta}, where \sigma is
the cluster velocity dispersion, and \beta~4. It appears that Upsilon_V is an
increasing function of cluster mass for compact clusters and ultra-compact
dwarf galaxies. We show that this is unlikely to be due to the presence of
non-baryonic dark matter, by comparing clusters to Milky Way satellite
galaxies, which are dark matter dominated. The satellite galaxies appear to
have a fixed mass inside a fiducial radius, M(r=r_0)=const.Comment: 19 pages, 10 figures, to appear in the Astrophysical Journa
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