The synaptic surface of the acetylcholine receptor in membranes from Torpedo californica electric organ has been imaged by scanning tunneling microscopy. The molecule appears pentameric, with one major and four minor protrusions rising above the surface, and these protrusions encompass a large central cavity. The outer diameter of the molecule is 69 +/- 10 A, while the diameter of the cavity, m...

Rabbit ovarian microvasculature, with particular regard to developing and atretic follicles, was studied by scanning electron microscopy (SEM) of vascular corrosion casts. The microvascular network of the follicles was arranged in typical round plexuses of varying shape and size. Four different morphological types of vascular plexuses supplied the follicles: Type 1 (100-250 microns in diameter)...

Background and aim: The main factor that influences the durability of dental restorations is secondary caries. Antibacterial activity of dental materials is important from the clinical aspect, as it might inhibit recurrent caries. The aim of the present study was to compare the antibacterial activity of four fluoride-releasing dental cavity liners against Streptococcus mutans (S. mutans) and La...

OBJECTIVE Our objective was to report safety and efficacy of stereotactic radiosurgery (SRS) to the surgical bed following resection of brain metastases. METHODS Eighty-seven consecutive patients who underwent cavity-directed SRS to the operative bed for the treatment of brain metastases between 2002 and 2010 were evaluated. SRS required a gadolinium-enhanced, high-resolution, T1-weighted mag...

BACKGROUND Adhesive systems have enabled clinicians to preserve more tooth structure by changing cavity designs. However, because of the polymerization shrinkage adhesive systems are not capable of totally prohibiting the gap formation between the cavity and restorative material of composite resin leading to colonization of oral microorganisms from saliva. One possible solution for this serious...

The infrastructure of the contractile vacuole of Ochromonas and Poterioochromonas species is described. It appears to be a permanent structure in the anterior end of the phytoflagellate, consisting of a central cavity with a unit-membrane lining from which flattened saccules protrude in all directions. The contracted saccules are about 40 nm in diameter and are made up of a single trilammellar ...

BACKGROUND AND AIMS Tree diameter, tree height and canopy closure have been described by previous meta-analyses as being important characteristics in roost selection by cavity-roosting bats. However, size and direction of effects for these characteristics varied greatly among studies, also referred to as heterogeneity. Potential sources of heterogeneity have not been investigated in previous me...

Background. Traditional Chinese postpartum care is believed to help in the recovery of women after delivery. Objective. This study investigated the association of elements in dietary and herbal therapy with uterine involution. Methods. Indices of uterine involution were measured ultrasonographically in 127 postpartum women between 4-6 weeks after delivery. A self-reported retrospective question...

The narrow emission of a single carbon nanotube at low temperature is coupled to the optical mode of a fiber microcavity using the built-in spatial and spectral matching brought by this flexible geometry. A thorough cw and time-resolved investigation of the very same emitter both in free space and in cavity shows an efficient funneling of the emission into the cavity mode together with a strong...

In our continuous wave cavity ring-down spectroscopy (CW-CRDS) experiments, we have often observed that the decay time constant drops to a lower value at some cavity lengths or some intercavity pressures. The resulting instabilities lead to a reduction in the sensitivity of our CRDS system. We have deduced that the cause of this noise is the coupling between the TEM(00) mode that the laser exci...