Search results for "tilt"
showing 10 items of 124 documents
Is backward disequilibrium in the elderly caused by an abnormal perception of verticality? A pilot study
2007
International audience; OBJECTIVE: We hypothesised that backward disequilibrium (BD), defined by a posterior position of the centre of mass with respect to the base of support, could be caused by a backward tilt in the perception of verticality. METHODS: The relationship between BD, the perception of verticality, and the history of falls in 25 subjects aged 84.5+/-7.4 years was analysed. An original ordinal scale, the BD scale (BDS), was used to quantify BD. Postural (PV) and haptic verticals (HV) were measured in sagittal plane. RESULTS: BDS scores closely correlated with the number of falls (r = 0.81, p =10(-5)). The more the PV was tilted backward, the greater the BDS scores (r = -0.95, …
Tilted phases of fatty acid monolayers
1995
X‐ray diffraction data from water‐supported monolayers of fatty acids with chain lengths from 19 to 22 is presented. The structures of the tilted mesophases L2’, L2, and Ov are characterized in detail. The contributions to the unit cell distortion from the tilt and the ordering of the backbone planes of the molecules are separated. It is shown that at the swiveling transition L2’–L2, not only the tilt azimuth but also the packing of the backbone planes change discontinuously. We demonstrate that the tilting transition LS–L2 is accompanied by the ordering of the backbone planes and may be discontinuous. Evidence is presented for a herringbone ordering transition within the L2 region. The dis…
Information Decomposition: A Tool to Dissect Cardiovascular and Cardiorespiratory Complexity
2017
This chapter reports some recent developments of information-theoretic concepts applied to the description of coupled dynamical systems, which allow to decompose the entropy of an assigned target system into components reflecting the information stored in the system and the information transferred to it from the other systems, as well as the nature (synergistic or redundant) of the information transferred to the target. The decomposition leads to well-defined measures of information dynamics which in the chapter will be defined theoretically, computed in simulations of linear Gaussian systems and implemented in practice through the application to heart period, arterial pressure and respirat…
Eröffnungsfeier des Passagierverkehrs in Riga vom neuen Bahnhof "Riga-Glawnaja" (Haupt-Bahnhof) über die neue Düna-Eisenbahnbrücke
1914
Teksts paralēli krievu, vācu un latviešu valodā.
Geometrical analysis of self-compensating suspension systems for railcar engineering
2002
The present analysis addresses several passive tilt systems for railroad cars aiming to compensate for the cart deficiency on curved tracks. To this end, the virtual centre of suspension must be located as close as possible to the longitudinal plane of symmetry of the coach, above the mass centre level for stability reasons. On the one hand, pantograph or Peaucellier's mechanisms may achieve the correct self-compensation. On the other hand, simpler articulated systems yield the desired goal with an excellent approximation. For example, selective algorithms can be applied for designing eight-link mechanisms, to be optimized thereafter by some method of the gradient type, minimizing the mean…
Hipertensión arterial episódica asociada al síndrome de taquicardia postural ortostática
2006
Se presenta el caso clínico de una mujer de 17 años de edad que acude en reiteradas ocasiones a urgencias por palpitaciones, taquicardia, síncope, reacción vegetativa de escasa duración, con recuperación espontánea y completa y detección de cifras elevadas de presión arterial. Estudiada en diversas consultas de especialidades y tras múltiples exploraciones complementarias no se encontró patología que justificase el cuadro. Ante la sospecha de intolerancia ortostática o síndrome de taquicardia postural ortostática con hipertensión se realizó la prueba de estimulación con cama basculante a 60°, confirmándose el diagnóstico y comprobando la desaparición de los síntomas al iniciar tratamiento c…
Quantifying multidimensional control mechanisms of cardiovascular dynamics during multiple concurrent stressors
2021
Heartbeat regulation is achieved through different routes originating from central autonomic network sources, as well as peripheral control mechanisms. While previous studies successfully characterized cardiovascular regulatory mechanisms during a single stressor, to the best of our knowledge, a combination of multiple concurrent elicitations leading to the activation of different autonomic regulatory routes has not been investigated yet. Therefore, in this study, we propose a novel modeling framework for the quantification of heartbeat regulatory mechanisms driven by different neural routes. The framework is evaluated using two heartbeat datasets gathered from healthy subjects undergoing p…
IEEE 802.1ah realizācija
2016
IEEE 802.1ah apraksta Provider Backbone Bridge (PBB) funkcionalitāti, kuras mērķis ir savienot dažādu veidu citu IEEE 802.1 standartos aprakstīto tiltu tīklus vienā lokālajā tīklā. Maģistra darba mērķis ir izpētīt IEEE 802.1ah darbību un prasības, kā arī veikt realizāciju šim standartam iekš Linux kodola. Darbā tiek aprakstīti iepriekšējie IEEE 802.1 standarti, uz kuriem balstās 802.1ah standarts, kā arī pats IEEE 802.1ah standarts. Pēc tam tiek apskatīta IEEE 802.1ah pieejamība pasaulē un citas realizācijas. Visbeidzot tiek sniegts ieskats Linux kodola tīklošanas apakšsistēmā, tiek aprakstīta IEEE 802.1ah realizācija, kas ir veikta, Linux kodola tilta modulī, un tiek aprakstīta tās testēša…
Gaussian models for the distribution of Brownian particles in tilted periodic potentials
2011
We present two Gaussian approximations for the time-dependent probability density function (PDF) of an overdamped Brownian particle moving in a tilted periodic potential. We assume high potential barriers in comparison with the noise intensity. The accuracy of the proposed approximated expressions for the time-dependent PDF is checked with numerical simulations of the Langevin dynamics. We found a quite good agreement between theoretical and numerical results at all times.
Spinopelvic changes based on the simplified SRS-Schwab adult spinal deformity classification: relationships with disability and health-related qualit…
2018
Study design Cross-sectional, observational study. Objective To study the occurrence of sagittal malalignment, the adaptability of a simplified sagittal modifiers grading of the Scoliosis Research Society (SRS)-Schwab adult spinal deformity (ASD) classification, and the deformity-specific SRS questionnaire version 30 (SRS-30) in an unselected adult cohort with symptomatic degenerative spinal disorders. Summary of background data The sagittal modifiers of the SRS-Schwab ASD classification correlate with health-related quality of life (HRQoL) measures in patients with ASD. The deformities and disabilities caused by sagittal malalignment in patients with common degenerative spinal disorders of…