Herleitung verbesserter hierarchischer Plattenmodelle und deren Integralgleichungsformulierung [online]

Abstract The objective of this dissertation is the derivation of a hierarchical formulation for the differential and integral equations of a twelfth-order plate bending model for homogeneous transversely isotropic materials, named after Poniatovskii and Reissner. The hierachical characteristic means that the direct reduction from the twelfth-order equation system automatically leads to corresponding systems of lower-order. By the first simplification we obtain the sixth-order equation system of Reissner (and Mindlin) and, by taking the limit of the thickness to zero or the shear stiffness to infinity, the fourth-order Kirchhoff bending equation. The simplification from the twelfth-order to the sixth-order system is performed by the selection of particular values for the two coupling variables. The differential equations of the twelfth-order model are obtained by application of the Hellinger-Reissner mixed variational principle. For the dimensional reduction we propose as starting point an expansion of the displacements along the plate thickness in the form of Legendre polynomials. In the sequel we determine the corresponding stress field in order to evaluate the expression for the complementary energy density to be used in the variational principle. The weighted residual method leads to the corresponding system of hierarchical integral equations allowing for the simultaneous BEM formulation of both, the sixth-order and the twelfth-order plate models. It is shown that the system of differential equations gives a better approximation of the three-dimensional elasticity equations than displacement-based models. The hierarchical reduction of the twelfth-order integral equations yields the known sixth-order equations of van der Weeen, now for transversely isotropic materials

ACANTHOSTOMUM GNERII SZIDAT, 1954 (DIGENEA: CRYPTOGONIMIDAE) DE RHAMDIA QUELEN (QUOY & GAIMARD, 1824)

Acanthostomum gnerii és un digenea frecuentemente reportado en el intestino de Siluriformes y bien distribuida en el centro y suramérica. El objetivo de este estudio es proporcionar información adicional sobre las características morfológicas de la A. gnerii por secciones histológicas y microscopio electrónico de barrido, así como para proporcionar mediciones comparativas de Acanthostomum spp.. Diferente de registros anteriores de este helminto en Rhamdia sp., los espécimes de presente estudio presentearon dos brazos en la porción anterior del cuerpo luego después de la faringe. Ellos se juntan en un poro lateral en el lado esquierdo del cuerpo semelhante al observado en A. proctophorum y A. minimum. Esta morfología no hay sido descripta como característica válida para Acanthostomidae. La variación morfológica podria estar asociada a diferentes poblaciones de la misma especie. Nuevos estudios usando tecnicas moleculares son recomendados para certificar se esta característica coresponde a la diversidad de A. gnerii encuentrada en otras especies de peces

Alternative scapular stabilization exercises to target strength, endurance and function of shoulders in tetraplegia: a prospective non-controlled intervention study

Scapular stabilization exercises (SSE) are well-established for the able-bodies. The aim of the current study is to access the potential benefits of SSE on isometric internal and external rotator strength, endurance and function of the shoulder in persons with tetraplegia, throughout a 12-week exercise program consisting of five resisted movements with elastic bands. Design: Prospective non-controlled intervention study. Setting/Participants/Interventions: A convenience sample of 17 subjects (age, 40.010.0 years old) with SCI was recruited from the University Hospital at the State University of Campinas (UNICAMP) from March 2015 to February 2016. They performed 5-resisted-SSE for 12 weeks, using Thera-band (R) elastic bands. Four evaluations were required: Baseline1, Baseline2, 6W and 12W. Outcome measures: The dependent variables were isometric internal and external rotation strength, flexion and abduction endurance and the Disabilities of the Arm, Shoulder and Hand (DASH) score. Results: Isometric external rotation strength and flexion endurance increased after SSE and were classified as "clinically relevant" using minimal importance difference (MID). Abduction endurance increased but it was classified as "not clinically relevant". DASH score reported no significant differences but it was classified as "potentially clinically relevant". Correlations were observed among time since injury and endurance improvements. Conclusion: This study demonstrated that specific training of the scapula muscles shows a benefit for shoulder strength, endurance and function of the shoulder in subjects with tetraplegia and should be part of the rehabilitation program. Besides, the SSE can be performed by subjects with tetraplegia themselves on a regular basis.4216576CNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP – Fundação de Amparo à Pesquisa Do Estado De São PauloSem informaçãoSem informaçã

Predictive value of the pendulum test for assessing knee extensor spasticity

Abstract Background The pendulum test is commonly used to quantify knee extensor spasticity, but it is currently unknown to what extent common pendulum test metrics can detect spasticity in patients with neurological injury or disease, and if the presence of flexor spasticity influences the test outcomes. Methods A retrospective analysis was conducted on 131 knees, from 93 patients, across four different patient cohorts. Clinical data included Modified Ashworth Scale (MAS) scores for knee extensors and flexors, and years since diagnosis. BioTone™ measures included extensor strength, passive and active range of motion, and pendulum tests of most affected or both knees. Pendulum test metrics included the relaxation index (RI), 1st flexion amplitude (F1amp) and plateau angle (Plat), where RI=F1amp/Plat. Two-way ANOVA tests were used to determine if pendulum test metrics were influenced by the degree of knee flexor spasticity graded by the MAS, and ANCOVA was used to test for confounding effects of age, years since injury, strength and range of motion (ROM). In order to identify the best pendulum test metrics, Receiver Operator Characteristic analysis and logistic regression (LR) analysis were used to classify knees by spasticity status (none or any) and severity (low/moderate or high/severe). Results Pendulum test metrics for knee extensors were not influenced by degree of flexor spasticity, age, years since injury, strength or ROM of the limb. RI, F1amp and Plat were > 70% accurate in classifying knees by presence of clinical spasticity (from the MAS), but were less accurate (< 70%) for grading spasticity level. The best classification accuracy was obtained using F1amp and Plat independently in the model rather than using RI alone. Conclusions We conclude that the pendulum test has good predictive value for detecting the presence of extensor spasticity, independent of the existence of flexor spasticity. However, the ability to grade spasticity level as measured by MAS using the RI and/or F1amp may be limited. Further study is warranted to explore if the pendulum test is suitable for quantifying more severe spasticity