820 resultados para contours


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Local rates of change in ice-sheet thickness were calculated at IS sites in West Antarctica using the submergence velocity technique. This method entails a comparison of the vertical velocity of the ice sheet, measured using repeat global positioning system surveys of markers, and local long-term rates of snow accumulation obtained using firn-core stratigraphy. Any significant difference between these two quantities represents a thickness change with time. Measurements were conducted at sites located similar to 100-200 km apart along US ITASE traverse routes, and at several isolated locations. All but one of the sites are distributed in the Siple Coast and the Amundsen Sea basin along contours of constant elevation, along flowlines, across ice divides and close to regions of enhanced flow. Calculated rates of thickness change are different from site to site. Most of the large rates of change in ice thickness (similar to 10 cm a(-1) or larger) are observed in or close to regions of rapid flow, and are probably related to ice-dynamics effects. Near-steady-state conditions are calculated mostly at sites in the slow-moving ice-sheet interior and near the main West Antarctic ice divide. These results are consistent with regional estimates of ice-sheet change derived from remote-sensing measurements at similar locations in West Antarctica.

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The present paper is an abridged version of the first chapter to the book EC Electronic Communications and Competition Law (London: Cameron May, 2007). It is intended to pinpoint the contours of the communications sector as an object of regulation - an exercise that is essential to any thoughts on appropriate regulatory design. The communications sector is defined through its salient features of being (i) network-bound; (ii) dynamic; (iii) converging; (iv) sensitive to regulation and society’s reactions; and as one (v) with special societal role and as (vi) part of the new economy.

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The recurrent interaction among orientation-selective neurons in the primary visual cortex (V1) is suited to enhance contours in a noisy visual scene. Motion is known to have a strong pop-up effect in perceiving contours, but how motion-sensitive neurons in V1 support contour detection remains vastly elusive. Here we suggest how the various types of motion-sensitive neurons observed in V1 should be wired together in a micro-circuitry to optimally extract contours in the visual scene. Motion-sensitive neurons can be selective about the direction of motion occurring at some spot or respond equally to all directions (pandirectional). We show that, in the light of figure-ground segregation, direction-selective motion neurons should additively modulate the corresponding orientation-selective neurons with preferred orientation orthogonal to the motion direction. In turn, to maximally enhance contours, pandirectional motion neurons should multiplicatively modulate all orientation-selective neurons with co-localized receptive fields. This multiplicative modulation amplifies the local V1-circuitry among co-aligned orientation-selective neurons for detecting elongated contours. We suggest that the additive modulation by direction-specific motion neurons is achieved through synaptic projections to the somatic region, and the multiplicative modulation by pandirectional motion neurons through projections to the apical region of orientation-specific pyramidal neurons. For the purpose of contour detection, the V1-intrinsic integration of motion information is advantageous over a downstream integration as it exploits the recurrent V1-circuitry designed for that task.

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Digital game environments are of increasing economic, social and cultural value. As their influence on diverse facets of life grows, states have felt compelled to intervene and secure some public interests. Yet, the contours of a comprehensive governance model are far from recognisable and governments are grappling with the complexity and fluidity of online games and virtual worlds as private spaces and as experimentation fields for creativity and innovation. This book contributes to a more comprehensive and fine-grained understanding of digital game environments, which is a precondition for addressing any of the pressing governance questions posed. Particular attention is given to the concept and policy objective of cultural diversity, which also offers a unique entry point into the discussion of the appropriate legal regulation of digital games. Governance of Digital Game Environments and Cultural Diversity will be of interest to researchers of media law, internet law and governance, cultural studies, anthropology and sociology. As the book addresses a highly topical theme, it will attract the attention of policymakers at national, regional and international levels and will also serve as a great resource tool for scholars in new media and, in particular, digital games and virtual worlds.

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BACKGROUND Finding the right balance between tibial coverage and minimal implant overhang is an important factor in TKA. Another significant cause of failure is component malrotation. METHODS An average master shape of the proximal tibia at TKA resection level was calculated using fine slice computed tomographies of 117 cadaveric knees. To find out whether alternate implant contours would be necessary depending on the patient's body size, we established five subgroups to compare. CAD-Analysis was performed to simulate the overhang produced after ±4°/±7°/±10° rotation. RESULTS A master shape for the tibial resection cut (with a 5° posterior slope, 7 mm under lateral joint line) could be determined. Neither left vs. right knee joint, nor male vs. female nor the size subdivision appears to alter the calculated master shape significantly. The optimized shape allowing for ±4° of rotational freedom was found to be the best variant. CONCLUSIONS Valid methods have been obtained to design a two-dimensional average shape of the tibial plateau. The modifications described in this study might come in useful, when designing future implant designs. CLINICAL RELEVANCE An optimized fit at the tibial plateau and lower rates of component malrotation may result in better outcomes after TKA.

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La práctica publicitaria se caracteriza por cultivar un discurso apelativo con fines persuasivos dirigido a un amplio público, hecho por el cual se difunde por medios de comunicación masivos. Por otro lado, la publicidad, sea cual fuere el género que utiliza para la transmisión del mensaje, cuenta solo con segundos para llamar la atención de su público destinatario y con escasos minutos para hacer llegar su mensaje. Debido a estos rasgos comunicactivos, el estereotipo se presenta como un mecanismo discursivo perfecto para que su público recepcione el mensaje suasivo, como ejemplificaré la publicidad de cerveza, objetivo de esta contribución. Desde luego, el tema de los estereotipos en publicidad no resulta nada novedoso; todo lo contrario: existen muchos trabajos que se han ocupado de ello . Pero el problema reside en el hecho de que por lo general se presenta la noción de estereotipo a priori como un fenómeno familiar y de conocimiento general, pero que en realidad se maneja con una borrosidad conceptual enorme, sin que se deslinden teóricamente los diferentes niveles en los que puede moverse ni sus diversas clases (Dufays 2010: 59-60). Por eso Amossy (1989: 29) dice sobre el concepto de estereotipo con razón: «fréquemment mentionné, utilisé comme critère de valeur et comme instrument d'analyse, le stéreéotype reste [...] une notion vague dont on connaît mal les contours, et dont les fonctions demeurent controversées». En efecto, el terreno de los trabajos teóricos sobre el estereotipo sigue siendo terra relativamente incognita. Por tal motivo, para exponer y explicar de qué manera se manejan los estereotipos en publicidad de cerveza, propondré un modelo de clasificación. Esta propuesta descansa en la combinación de alcances teóricos de la psicología social del lenguaje (Moscovici 1984), incluidos los de la teoría de la relevancia de Sperber y Wilson (1986) con aquellos provenientes de la lingüística del discurso con fuerte influjo estilístico y retórico, como los que proponen Amossy ( 1991), Amossy / Herrschberger (1997) y Dufays (2010) . He considerado en el análisis dos géneros: la cuña audiovisual y el reclamo, porque partía de la idea de que las características mediales influyen en las técnicas de tratamiento del estereotipo. Dado que entiendo el discurso y su producto –los textos– como una actividad comunicactiva semiótica, tomo en cuenta para el análisis del estereotipo tanto la manifestación lingüística como la icónica.

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In the introduction to this special issue on Sociolinguistics and Tourism, we focus on language in tourism as an important window into contemporary forms of economic, political, and social change. Our aim is twofold: (1) to establish and extend ‘sociolinguistics and tourism’ as another social and applied domain of sociolinguistic research; and (2) to use tourism as a lens for a broader discussion of the sociolinguistics of late modernity. To this end, we outline the contours of language and tourism research to date; we consider the (re)conceptualization of key thematics or notions in sociolinguistic research – such as ‘community’, ‘identity’, and ‘language’ itself – as particularly germane to the study of tourism's fleeting encounters; we examine the inevitable tensions between commodification and authenticity; and we explore the links between performances of ‘self’ and ‘other’, and the contestation of different identity positions with regard to social actors’ multilingual repertoires. We illustrate these issues with data examples from several tourist sites, where multilingual resources are deployed for identification, authentication and commodification. Finally, we briefly introduce the papers in this special issue and conclude by commenting on some sociolinguistic consequences of the study of language/s in tourism.

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The S0 → S1 vibronic spectrum and S1 state nonradiative relaxation of jet-cooled keto-amino 5-fluorocytosine (5FCyt) are investigated by two-color resonant two-photon ionization spectroscopy at 0.3 and 0.05 cm–1 resolution. The 000 rotational band contour is polarized in-plane, implying that the electronic transition is 1ππ*. The electronic transition dipole moment orientation and the changes of rotational constants agree closely with the SCS-CC2 calculated values for the 1ππ* (S1) transition of 5FCyt. The spectral region from 0 to 300 cm–1 is dominated by overtone and combination bands of the out-of-plane ν1′ (boat), ν2′ (butterfly), and ν3′ (HN–C6H twist) vibrations, implying that the pyrimidinone frame is distorted out-of-plane by the 1ππ* excitation, in agreement with SCS-CC2 calculations. The number of vibronic bands rises strongly around +350 cm–1; this is attributed to the 1ππ* state barrier to planarity that corresponds to the central maximum of the double-minimum out-of-plane vibrational potentials along the ν1′, ν2′, and ν3′ coordinates, which gives rise to a high density of vibronic excitations. At +1200 cm–1, rapid nonradiative relaxation (knr ≥ 1012 s–1) sets in, which we interpret as the height of the 1ππ* state barrier in front of the lowest S1/S0 conical intersection. This barrier in 5FCyt is 3 times higher than that in cytosine. The lifetimes of the ν′ = 0, 2ν1′, 2ν2′, 2ν1′ + 2ν2′, 4ν2′, and 2ν1′ + 4ν2′ levels are determined from Lorentzian widths fitted to the rotational band contours and are τ ≥ 75 ps for ν′ = 0, decreasing to τ ≥ 55 ps at the 2ν1′ + 4ν2′ level at +234 cm–1. These gas-phase lifetimes are twice those of S1 state cytosine and 10–100 times those of the other canonical nucleobases in the gas phase. On the other hand, the 5FCyt gas-phase lifetime is close to the 73 ps lifetime in room-temperature solvents. This lack of dependence on temperature and on the surrounding medium implies that the 5FCyt nonradiative relaxation from its S1 (1ππ*) state is essentially controlled by the same ∼1200 cm–1 barrier and conical intersection both in the gas phase and in solution.

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High-resolution esophageal manometry (HRM) is a recent development used in the evaluation of esophageal function. Our aim was to assess the inter-observer agreement for diagnosis of esophageal motility disorders using this technology. Practitioners registered on the HRM Working Group website were invited to review and classify (i) 147 individual water swallows and (ii) 40 diagnostic studies comprising 10 swallows using a drop-down menu that followed the Chicago Classification system. Data were presented using a standardized format with pressure contours without a summary of HRM metrics. The sequence of swallows was fixed for each user but randomized between users to avoid sequence bias. Participants were blinded to other entries. (i) Individual swallows were assessed by 18 practitioners (13 institutions). Consensus agreement (≤2/18 dissenters) was present for most cases of normal peristalsis and achalasia but not for cases of peristaltic dysmotility. (ii) Diagnostic studies were assessed by 36 practitioners (28 institutions). Overall inter-observer agreement was 'moderate' (kappa 0.51) being 'substantial' (kappa > 0.7) for achalasia type I/II and no lower than 'fair-moderate' (kappa >0.34) for any diagnosis. Overall agreement was somewhat higher among those that had performed >400 studies (n = 9; kappa 0.55) and 'substantial' among experts involved in development of the Chicago Classification system (n = 4; kappa 0.66). This prospective, randomized, and blinded study reports an acceptable level of inter-observer agreement for HRM diagnoses across the full spectrum of esophageal motility disorders for a large group of clinicians working in a range of medical institutions. Suboptimal agreement for diagnosis of peristaltic motility disorders highlights contribution of objective HRM metrics.

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In clinical practice, traditional X-ray radiography is widely used, and knowledge of landmarks and contours in anteroposterior (AP) pelvis X-rays is invaluable for computer aided diagnosis, hip surgery planning and image-guided interventions. This paper presents a fully automatic approach for landmark detection and shape segmentation of both pelvis and femur in conventional AP X-ray images. Our approach is based on the framework of landmark detection via Random Forest (RF) regression and shape regularization via hierarchical sparse shape composition. We propose a visual feature FL-HoG (Flexible- Level Histogram of Oriented Gradients) and a feature selection algorithm based on trace radio optimization to improve the robustness and the efficacy of RF-based landmark detection. The landmark detection result is then used in a hierarchical sparse shape composition framework for shape regularization. Finally, the extracted shape contour is fine-tuned by a post-processing step based on low level image features. The experimental results demonstrate that our feature selection algorithm reduces the feature dimension in a factor of 40 and improves both training and test efficiency. Further experiments conducted on 436 clinical AP pelvis X-rays show that our approach achieves an average point-to-curve error around 1.2 mm for femur and 1.9 mm for pelvis.

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A measurement of the B 0 s →J/ψϕ decay parameters, updated to include flavor tagging is reported using 4.9  fb −1 of integrated luminosity collected by the ATLAS detector from s √ =7  TeV pp collisions recorded in 2011 at the LHC. The values measured for the physical parameters are ϕ s 0.12±0.25(stat)±0.05(syst)  rad ΔΓ s 0.053±0.021(stat)±0.010(syst)  ps −1 Γ s 0.677±0.007(stat)±0.004(syst)  ps −1 |A ∥ (0)| 2 0.220±0.008(stat)±0.009(syst) |A 0 (0)| 2 0.529±0.006(stat)±0.012(syst) δ ⊥ =3.89±0.47(stat)±0.11(syst)  rad where the parameter ΔΓ s is constrained to be positive. The S -wave contribution was measured and found to be compatible with zero. Results for ϕ s and ΔΓ s are also presented as 68% and 95% likelihood contours, which show agreement with the Standard Model expectations.

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A search for an excess of events with multiple high transverse momentum objects including charged leptons and jets is presented, using 20.3 fb−1 of proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2012 at a centre-of-mass energy of √s = 8TeV. No excess of events beyond Standard Model expectations is observed. Using extra-dimensional models for black hole and string ball production and decay, exclusion contours are determined as a function of the mass threshold for production and the fundamental gravity scale for two, four and six extra dimensions. For six extra dimensions, mass thresholds of 4.8–6.2TeV are excluded at 95% confidence level, depending on the fundamental gravity scale and model assumptions. Upper limits on the fiducial cross-sections for non-Standard Model production of these final states are set.

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This article explores nostalgia’s multi-facetted character by linking its discursive and experiential dimensions. In a first move I highlight its importance as an analytical category that grew out of a very particular history of knowledge. Focusing on a specific case that played a crucial role in the two distinct phases of nostalgia as a concept I show how it has come to be inextricably linked to ideas of displacement and loss. In a second move I juxtapose this metaphorical treatment of loss and nostalgia with a focus on the lifeworld of one individual who has experienced physical displacement. In focusing on two particular nostalgic moments in her life, I sketch the contours of an anthropological phenomenology of nostalgia

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PURPOSE To investigate interobserver variations of target volume delineations in accelerated partial breast irradiation with multicatheter brachytherapy (BT) and to assess the impact of guidelines on consistency of contouring. METHODS AND MATERIALS A contouring study with two phases in interstitial accelerated partial breast irradiation after open cavity surgery was conducted by the Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology Breast Cancer Working Group. Contours of cavity and planning target volume (PTV) on preimplant and postimplant CT images were delineated. In Phase 1, nine radiation oncologists defined the target volumes of 5 patients, whereas in Phase 2, four observers draw the contours of 4 patients applying guidelines. In Phase 1, experience in breast BT after open cavity surgery was assessed. The delineations were compared between Phase 1 and Phase 2, the impact of guidelines was assessed, and cavity visualization score was related to consistency of delineations. RESULTS Significant interobserver variability in delineations of lumpectomy cavity and PTV was observed among the participants. Observers with BT experience after open cavity surgery outlined the cavity and PTV more consistently (conformity indexgen: 0.52 vs. 0.48 and 0.59 vs. 0.55 for preimplant and postimplant cavities). For all volumes, the mean Vmax/Vmin was 2.2 vs. 2.8. Having used guidelines all conformity indices increased significantly. For cavity, the increase was 14% and 11%, whereas for the PTV, 28% and 17% on the preimplant and postimplant CT images, respectively. A strong correlation was found between consistency of contours and cavity visualization score. CONCLUSIONS Simple guidelines on defining the lumpectomy cavity significantly increased the consistency of contouring. Reliable consistency of target volume definition can be expected only for good cavity visibility.

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Aims. We report on the first major temporal morphological changes observed on the surface of the nucleus of comet 67P/Churyumov-Gerasimenko in the smooth terrains of the Imhotep region. Methods. We used images of the OSIRIS cameras onboard Rosetta to follow the temporal changes from 24 May 2015 to 11 July 2015. Results. The morphological changes observed on the surface are visible in the form of roundish features that are growing in size from a given location in a preferential direction at a rate of 5.6-8.1 x 10(-5) m s(-1) during the observational period. The location where the changes started and the contours of the expanding features are bluer than the surroundings, which suggests that ices (H2O and/or CO2) are exposed on the surface. However, sublimation of ices alone is not sufficient to explain the observed expanding features. No significant variations in the dust activity pattern are observed during the period of changes.