introduction: the aim of this study was to identify the root and canal morphology of maxillary first and second molars in iranian population by taking and analyzing cone-beam computed tomography (cbct) scans. methods and materials: extracted maxillary first ( n =125) and second ( n =125) molars were collected from native iranians and scanned by using a cbct scanner. the number of roots and conf...

We report the diagnosis and successful clinical management of three patients with anatomical variation in the maxillary first premolars. Maxillary first premolars have highly variable root canal morphology, but the presence of three canals is rare. This article describes the diagnosis and clinical management of first maxillary premolars with three canals and three separate roots, with special r...

We report on the measurement of morphology-dependent resonance within a laser-trapped micro-sphere excited under two-photon absorption. Both trapping and two-photon excitation are simultaneously achieved by a single femtosecond pulsed laser beam. The effect of the laser power as well as the pulse width on the transverse trapping force is first investigated. The dependence of two-photon-induced ...

We report scanning tunneling microscopy (STM) images of surfaces of GaN films and the observation of luminescence from those films induced by highly spatially localized injection of electrons or holes using STM. This combination of scanning tunneling luminescence (STL) with STM for GaN surfaces and the ability to observe both morphology and luminescence in GaN is the first step to investigate p...

After giving a brief overview of the renewal of interest in logic and the foundations of mathematics in Göttingen in the period 1914-1921, I give a detailed presentation of the approach to the foundations of mathematics found in Behmann’s doctoral dissertation of 1918, Die Antinomie der transfiniten Zahl und ihre Auflösung durch die Theorie von Russell und Whitehead. The dissertation was writte...