introduction: the main purpose of the present study was to describe the ultra structural changes which happened after treatment of the root surfaces with ultrasonic and hand devices followed by erbium-doped yttrium aluminum garnet (er:yag) laser irradiation. methods: sixty single-rooted maxillary and mandibular teeth which had been extracted due to periodontal problems were collected. crown and...

Virtually all fibers exhibit some dimensional and structural irregularities. These include the conventional textile fibers, the high-performance brittle fibers and even the newly developed nano-fibers. In recent years, we have systematically examined the effect of fiber dimensional irregularities on the mechanical behavior of the irregular fibers. This paper extends our research to include the ...

The weight-bearing surfaces of the lateral femoral condyles taken from twenty normal human cadavers aged 0-47 years have been examined by reflected light interference microscopy (RLIM) and by scanning electron microscope (SEM). The surfaces appeared normal by naked eye examination. The presence of both 200-400 mum diameter secondary undulations and small ovoid 20-45 mum diameter tertiary hollow...

Scanning electron microscopy was used to assess the morphological features of coagulase-negative staphylococci adherent to polyvinylchloride intravascular catheter specimens. Clinical specimens were obtained by using patient catheters from which coagulase-negative staphylococci (greater than or equal to 15 colonies per catheter) grew on semiquantitative blood agar roll cultures. In vitro specim...

Irregular buildings make up a large portion of  urban infrastructure. Presence of irregularities can be due to architectural and  user changes in building stories. Main objective of this article is evaluate seismic performance of structures with vertical irregularities. Seismic responses are obtained by enveloping peak inelastic responses resulting from pushover analyses according to provided p...