Functional expression of theSpodoptera exiguachitinase to examine the virtually screened inhibitor candidates

AbstractChitinase is responsible for insect chitin hydrolyzation, which is a key process in insect molting and pupation. However, little is known about the chitinase ofSpodoptera exigua(SeChi). In this study, based on theSeChi gene (ADI24346) identified in our laboratory, we constructed the recombinant baculovirus P-Chi for the expression of recombinantSeChi (rSeChi) in Hi5 cells. The rSeChi was purified by chelate affinity chromatography, and the purified protein showed activity comparable with that of a commercialSgChi, suggesting that we harvested activeSeChi for the first time. The purified protein was subsequently tested for enzymatic properties and revealed to exhibit its highest activity at pH 8 and 40 C. Using homology modeling and molecular docking techniques, the three-dimensional model ofSeChi was constructed and screened for inhibitors. In two rounds of screening, twenty compounds were selected. With the purified rSeChi, we tested each of the twenty compounds for inhibitor activity against rSeChi, and seven compounds showed obvious activity. This study provided new information for the chitinase of beet armyworm and for chitinase inhibitor development.

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Problems Associated with the Use of Skirts on Hovercraft

Proceedings of the Institution of Mechanical Engineers Automobile Division ◽

10.1243/pime_auto_1967_182_029_02 ◽

1967 ◽

Vol 182 (1) ◽

pp. 201-218

Author(s):

W. A. Crago

Keyword(s):

Three Dimensional ◽

Model Tests ◽

Dimensional Model ◽

Three Dimensional Model ◽

Operational Conditions ◽

The Third ◽

Rough Water ◽

Delamination Life ◽

First Time

The lecture commences with a brief description of early hovercraft work and shows how the advent of flexible extensions to the peripheral jets—or ‘skirts’—constituted a breakthrough without which the hovercraft would never have become a practical proposition with the ability to operate over waves and rough ground. It is shown that the introduction of skirts, whilst providing a solution in one respect, also led to a series of problems and three of these are singled out for further discussion. First it is shown that whilst a relatively high internal skirt pressure is desirable to maintain skirt shape under operational conditions, this pressure can also lead to a high rough water drag. The second problem is that of ‘plough in’ and overturning, which is intimately associated with the use of skins. The hydrodynamic mechanisms of both these undesirable phenomena are for the first time explained in detail and are illustrated by means of data obtained from two- and three-dimensional model tests. The third problem raised by the introduction of skirts is skirt oscillation and wear. The techniques necessary to investigate delamination are described and some of the factors which have been shown to be important in increasing delamination life are outlined.

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A Three-Dimensional Model of Droplet Impinging, Solidification and Suspension on the Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.346.222 ◽

2011 ◽

Vol 346 ◽

pp. 222-227

Author(s):

Sheng Zhu ◽

Feng Liang Yin ◽

Jian Liu ◽

Yuan Yuan Liang

Keyword(s):

Surface Tension ◽

Manufacturing Process ◽

Three Dimensional ◽

Metal Droplet ◽

The Body ◽

Dimensional Model ◽

Three Dimensional Model ◽

High Impact Velocity ◽

The Impact ◽

First Time

A three-dimensional model was built to study a molten metal droplet impact on an edge of the substrate in droplet deposition manufacturing process for the first time. The whole calculation domain, including the substrate, was described using same fluid conservation equations, which is to say that the remolding and solidification of substrate was considered also. Droplet free surface was tracked by volume-of-fluid (VOF) algorithm. The effect of surface tension on the droplet was taken into consideration by means of considering surface tension to be a component of the body force. The simulated results show that the droplet in liquid phase can keep suspending on the substrate at a role of surface tension. A too high impact velocity would make parts of droplet splash away the substrate which is not allowed in manufacturing process. The offset between edge of droplet and side edge of substrate influences dramatically the impact of the droplet.

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A Cat's Eye view of the Eskimo from Saturn

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312011453 ◽

2011 ◽

Vol 7 (S283) ◽

pp. 366-367 ◽

Cited By ~ 2

Author(s):

Maria-Teresa García-Díaz ◽

Jose-Alberto López ◽

Wofgang Steffen ◽

Michael G. Richer ◽

Hortensia Riesgo

Keyword(s):

Three Dimensional ◽

Line Of Sight ◽

Dimensional Model ◽

Three Dimensional Model ◽

Data Set ◽

Spatially Resolved ◽

Complex Morphology ◽

Spectroscopic Information ◽

Expansion Pattern ◽

First Time

AbstractThe 3-D and kinematic structure of the Eskimo nebula, NGC 2392, has been notoriously difficult to interpret given its complex morphology, multiple kinematic components and its nearly pole-on orientation along the line of sight. Here we present the most comprehensive high resolution spectroscopic mapping of the Eskimo planetary nebula to date. The data consist of 21 spatially resolved, long-slit echelle spectra tightly spaced over the Eskimo and along its bipolar jets. This data set allowed us to construct a velocity-resolved [NII] channel map of the nebula with a resolution of 10 km/s that disentagles the differente kinematic components of the nebula and reveals clearly for the first time the kinematic expansion pattern for each of the components. The spectroscopic information is combined with a HST image to construct the first detailed three dimensional model of the Eskimo with the code SHAPE. With this model we demostrate that the Eskimo is nearly a twin to the Saturn nebula, but rotated 90° to the line sight. Furthermore, we show that the main characteristics of our model apply to the general properties of the group of elliptical planetary nebulae with ansae, once the orientation is considered.

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