background retrograde intra-renal surgery (rirs) has been used to remove stones of less than 2 cm in the kidney. however, its role is not well defined. objectives the objective of this study was to evaluate the outcomes and safety of rirs, used either as a primary or secondary procedure, and to analyze factors predicting the stonefree rate (sfr). patients and methods a retrospective analysis wa...

This article reports studies on the feasibility of increasing the decoloring capacity of a granular activated carbon (GAC) by using oxidation with air at 350 degrees C to modify its surface activity and porosity. The GAC, obtained from olive stones, had a maximum decolorization capacity of 92% for doses of 20 g/l, while the maximum decolorization capacity of the modified granular activated carb...

     Salt crystallization is one of the most powerful weathering agents that may cause a rapid change in the mechanical properties of stones, and thus limit their durability. Consequently, determining the mechanical properties of stones due to salt crystallization is important for natural building stones used in marine environmental and mild climatic conditions, which expose excessive salt crys...

The molluscan shell can be viewed as a petrified representation of the organism's ontogeny and thus can be used as a record of changes in form during growth. However, little empirical data is available on the actual growth and form of shells, as these are hard to quantify and examine simultaneously. To address these issues, we studied the growth and form of a land snail that has an irregularly ...

The collective dynamics of liquid gallium close to the melting point has been studied using inelastic x-ray scattering to probe length scales smaller than the size of the first coordination shell. Although the structural properties of this partially covalent liquid strongly deviate from a simple hard-sphere model, the dynamics, as reflected in the quasielastic scattering, are beautifully descri...

In a series of publications the Cummings-Stell model (CSM), for a binary mixture of associative fluids with steric effects, has been solved analytically using the Percus-Yevick approximation (PYA). The solution consists in a square well potential of width w, whose center is placed into the hard sphere shell (r < σ): at L = σ/n (n = 1, . . . , 4). This paper presents a general solution, for any ...

BACKGROUND/AIM Primary therapeutic approach to lumbar ureteral stones is still contraversial. The aim of the study was to investigate the influence of stone impaction and size on the effectiveness of proximal ureteral stone lithotripsy. METHODS A total of 123 patients with proximal ureteral stones were investigated in this prospective study performed in a 10-month period. The patients were di...

This paper reports combined hydrophobicity and mechanical durability through the nanoscale engineering of surfaces in the form of nanorod-polymer composites. Specifically, the hydrophobicity derives from nanoscale features of mechanically hard ZnO nanorods and the mechanical durability derives from the composite structure of a hard ZnO nanorod core and soft polymer shell. Experimental character...