A an initial diagnostic procedure in diffuse and localized lung disease, transbronchial lung biopsy ( TBB ) offers an attractive alternative to open lung biopsy. In the past, TBB was carried out by inserting a flexible forceps through a rigid, opentube bronchoscope or a catheter.’5 More recently, this technique has been popularized by passing the forceps through the channel of a flexible fibero...

Voltage-gated sodium channels are vital membrane proteins essential for electrical signalling; in humans, they are key targets for the development of pharmaceutical drugs. Here we report the crystal structure of an open-channel conformation of NavMs, the bacterial channel pore from the marine bacterium Magnetococcus sp. (strain MC-1). It differs from the recently published crystal structure of ...

Flow boiling in microchannels and minichannels is being investigated for its potential for high heat flux removal in electronics and other devices. The small channel dimensions characteristic of these channels result, under most circumstances, in laminar flow at the flow rates used in these applications. The present work investigates the applicability of the correlation developed by Kandlikar a...

The ultrasonic pulse-echo backscattered amplitude integral (BAI)-mode imaging technique [IEEE Trans. UFFC, 45:30 (1998)] has demonstrated sensitive detection of subwavelength channel defects (38m diameter reliably and 6m diameter occasionally) in flexible 220m-thick food package seals (17.3 MHz, 86 m). However, the underlying subwavelength defect detection mechanism is poorly understood. In thi...

The study of crystals of molecular wheels as nanoporous materials is reported. Hyperpolarized (129)Xe NMR spectroscopy has been used to characterize the mode of molecular diffusion and Xe interactions within the supramolecular nanochannels formed upon crystallization of the molecular wheels [Ga(10)(OMe)(20)(O(2)CMe)(10)] and [Ga(18)(pd)(12)(pdH)(12)(O(2)CMe)(6)(NO(3))(6)](NO(3))(6). In agreemen...

insulator, and this in turn carries a 1-, in. brass rod, Q, fixed and sealed in position by a screw cap, R, and 0-ring gasket. The tungsten-anode wire, S (0-1 mm. diameter), is sheathed by a copper tube, T (diameter i16in.) to which it is soldered at its upper end. This is held in the rod, Q, by a small grubscrew. By this means the whole anode assembly is easily taken apart for cleaning and cha...

Pressure drop of ordered arrays of cylinders embedded inside microchannels is experimentally and analytically studied. Two independent modeling techniques are used to predict the flow resistance for the creeping flow regime. The pressure drop is expressed as a function of the involved geometrical parameters such as micro-cylinder diameter, spacing between adjacent cylinders, channel height, and...

The diameter, area, and volume of individual human erythrocytes (of 8 subjects, newborn to age 71) were determined by photographing the cells hanging on edge. Measurements from high magnification prints were processed by computer. The distributions of diameter, area, and volume are described statistically, with the unexpectedly linear regression equations for their interrelations. The plot of a...

A new material for microchannel plates (MCP) is proposed — anodic aluminum oxide. Microchannel plates made of this material may be much cheaper than with conventional lead glass MCP. Also a significantly smaller channel diameter (up to 70 nm) is easily achievable, which means better spatial resolution and the possibility to operate in strong magnetic fields. Methods and means are developed for ...

Although pore formation by protective antigen (PA) is critical to cell intoxication by anthrax toxin (AT), the structure of the pore form of PA (the PA63 pore) has not been determined. Hence, in this study, the PA63 pore was modeled using the X-ray structures of monomeric PA and heptameric alpha-hemolysin (alpha-HL) as templates. The PA63 pore model consists of two weakly associated domains, na...