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Ureteral triplication is one of the rarest malformations of the upper urinary tract. We report the case of a 12-year-old girl with right ureteral triplication combined with renal ectopia and ureteral cyst with stenosis at the junction of the ureteral cyst and distal ureter. The ureteral cyst was tailored and tubularized, and the tight junction was removed, as in Hynes-Anderson ureteropyeloplasty; on reevaluation almost 4 years later, kidney function was normal and computed tomography showed a normal kidney and ureter.

Recently spatial reasoning has gradually become a research hotspot in some domains such as GIS and spatiotemporal database. At present many spatio-temporal methods put forward by scholars are methods based on logic or algebra by and large, and researches on formalization representation and reasoning of geographic sptatio-temporal knowledge are few. Geo-ontology researches detailed connotations and hierarchy relationships of concepts of geographic spatial information in the geoinformatics domain and offers semantic annotations of concepts. Semantic and spatio-temporal relationships can fuse into geo-ontology and form knowledge base of geo-ontology. But OWL, an ontology representation language, can't describe determining and reasoning rules of spatio-temporal relationships owing on account of its limitation. At the same time SWRL can make up the deficiency of OWL, which implements the combination of Horn-like rules and OWL knowledge base by adopting highly abstract syntax to express knowledge represented by OWL ontology. This paper does a research on adopting geo-ontology to represent semantic and spatiotemporal relationships and applying SWRL to express spatio-temporal rules, which lays the solid foundation of spatio-temporal reasoning.

Couple stress formulations have been given much attention lately because of the possibility to explain cases, when the classical theory of elasticity fails to describe adequately the mechanical behavior. Such cases may include size-dependent stiffness, high stress gradients, and the response of materials with microstructure. Here, a new mixed Lagrangian formulation is developed for elastodynamic response within consistent size-dependent skew-symmetric couple stress theory. With a specific choice of mixed variables, the formulation can be written with only C 0 continuity requirements, without the need to introduce a Lagrange multiplier or penalty method. Furthermore, this formulation permits, for the first time, the determination of natural frequencies within the consistent couple stress theory. Details for the strong form of the equilibrium equations, constitutive model relations, boundary conditions, and the corresponding weak form are provided. In addition, the discrete forms are also discussed with two approaches for reducing variables. Several simple two-dimensional computational example problems are then examined, along with a brief investigation of the effect of couple stress on natural frequencies, which exhibit size-dependence for most, but not all, modes.