We propose a phase coexistence based mechanism for activity of helicases, ubiquitous enzymes that unwind double stranded DNA. The helicase-DNA complex constitutes a fixed-stretch ensemble that entails a coexistence of domains of zipped and unzipped phases of DNA, separated by a domain wall. The motor action of the helicase leads to a change in the position of the fixed constraint thereby shifti...

The uniformity requirements of direct-drive targets are <tringent. The requirements on both sphericity and wall thickness uniformity are of the order of less than 1%. In the past, dualbeam interference microscopy has been used at LLE to characterize the wall thickness and uniformity of transparent targets.' With this technique, an interference pattern is formed between one beam that passes thro...

Xyloglucan is a key polymer in the walls of growing plant cells. Using split pea stem segments and stem segments from which the epidermis had been peeled off, we demonstrate that the integration of xyloglucan mediated by the action of wall-bound xyloglucan endotransglycosylase suppressed cell elongation, whereas that of its fragment oligosaccharide accelerated it. Whole xyloglucan was incorpora...

A vacuum system (20) includes an enclosure (22) having a vacuum-tight wall (26) and an internally threaded aperture (66) through the wall (26). A tip-off fitting (24) has a base (50) with a bore (52) therethrough. a hollow tube (62) fixed to the base (50) with a vacuum-tight seal. such that an interior (64) of the tube (62) is in communication with the bore (52) in the base (50). and an externa...

A vacuum system (20) includes an enclosure (22) having a vacuum-tight wall (26) and an internally threaded aperture (66) through the wall (26). A tip-off fitting (24) has a base (50) with a bore (52) therethrough. a hollow tube (62) fixed to the base (50) with a vacuum-tight seal. such that an interior (64) of the tube (62) is in communication with the bore (52) in the base (50). and an externa...

A fully penetrating cut-off wall is a vertical seepage barrier that penetrates an aquifer and embedded in underlying aquitard to certain depth. Groundwater with this type of occurs through three paths: leakage the body aquifer, aquitard, under wall. Seepage first path can be simply treated as one-dimensional flow. However, due mutual influence latter two paths, problem complicated still needs s...

Spinal afferent neurons, with endings in the intestinal mesenteries, have been shown to respond to changes in vascular perfusion rates. The mechanisms underlying this sensitivity were investigated in an in vitro preparation of the mesenteric fan devoid of connections with the gut wall. Afferent discharge increased when vascular perfusion was stopped ("flow off"), a response localized to the ter...

External thermal insulation systems often have durability problems, including cracking, hollowing, and falling off, which seriously affect safety energy-saving effects. Based on finite element theory using ANSYS software, this paper studies the distribution law of temperature field stress external system. It was found that, compared with an uninsulated wall, substrate in summer reduced by 52.9%...

This paper presents the dynamics of microbubbles that are pinched-off and breakup in micro-jetting. A microjet is generated in two bubble interaction when a laser induced bubble is impacting a static gas bubble in a microchannel. Gas layers with a height of hundreds of nanometer are pinched off from the accelerated gas bubble wall during the jetting process. They are further modified by surface...