Quantifying the Separation of Positive and Negative Areas in Electrostatic Potential for Predicting Feasibility of Ammonium Sulfate for Protein Crystallization

2021 ◽  
Author(s):  
Yan Guo ◽  
Noritaka Nishida ◽  
Tyuji Hoshino
Keyword(s):  
Ammonium Sulfate ◽  
Electrostatic Potential ◽  
Protein Crystallization

Anisotropic Distribution of Ammonium Sulfate Ions in Protein Crystallization

2019 ◽  
Vol 19 (11) ◽  
pp. 6004-6010 ◽  
Author(s):  
Mariko Kitahara ◽  
Satoshi Fudo ◽  
Tomoki Yoneda ◽  
Michiyoshi Nukaga ◽  
Tyuji Hoshino
Keyword(s):  
Ammonium Sulfate ◽  
Protein Crystallization ◽  
Sulfate Ions

The Coagulation Abnormalities in Systemic Lupus Erythematosus

1968 ◽  
Vol 20 (03/04) ◽  
pp. 457-464 ◽  
Author(s):  
L Gonyea ◽  
R Herdman ◽  
R. A Bridges
Keyword(s):  
Systemic Lupus Erythematosus ◽  
Ammonium Sulfate ◽  
Lupus Erythematosus ◽  
Anticoagulant Activity ◽  
Species Specificity ◽  
Sensitive Assay ◽  
Systemic Lupus ◽  
Coagulation Abnormalities

SummaryAn anticoagulant occurring in 4 of 6 patients with SLE has been demonstrated by a sensitive assay utilizing an ammonium sulfate fraction of serum. The anticoagulant functions as an inhibitor of the activation of prothrombin. No species specificity was demonstrable. The inhibitor behaves clinically and chromatographically as an immunoglobulin, although an attempt to demonstrate directly the antibody nature of the inhibitor was not successful.A severe, apparently independent, decrease in the level of prothrombin was observed in the patient with hemorrhagic symptoms. In contrast to the anticoagulant activity, the low prothrombin has persisted during treatment.

Measurement System of Surface Electrostatic Potential on Insulation Board in Vacuum and its Application

2012 ◽  
Vol 132 (1) ◽  
pp. 95-100
Author(s):  
Hiroshi Morita ◽  
Ayumu Hatanaka ◽  
Toshiyuki Yokosuka ◽  
Yoshitaka Seki ◽  
Yoshiaki Tsumuraya ◽  
...  
Keyword(s):  
Electrostatic Potential ◽  
Measurement System ◽  
Surface Electrostatic Potential

Extraction and Partial Purification of Protease from Bilimbi (Averrhoa bilimbi L.)

2013 ◽  
Vol 10 (2) ◽  
pp. 29
Author(s):  
Normah Ismail ◽  
Nur' Ain Mohamad Kharoe
Keyword(s):  
Molecular Weight ◽  
Protein Content ◽  
Ammonium Sulfate ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Protease Activity ◽  
Protein Concentration ◽  
Temperature Stability ◽  
Partial Purification ◽  
Ammonium Sulfate Precipitation

Unripe and ripe bilimbi (Averrhoa bilimbi L.) were ground and the extracted juices were partially purified by ammonium sulfate precipitation at the concentrations of 40 and 60% (w/v). The collected proteases were analysed for pH, temperature stability, storage stability, molecular weight distribution, protein concentration and protein content. Protein content of bilimbi fruit was 0.89 g. Protease activity of both the unripe and ripe fruit were optimum at pH 4 and 40°C when the juice were purified at 40 and 60% ammonium sulfate precipitation. A decreased in protease activity was observed during the seven days of storage at 4°C. Molecular weight distribution indicated that the proteases protein bands fall between IO to 220 kDa. Protein bands were observed at 25, 50 and 160 kDa in both the unripe and ripe bilimbi proteases purified with 40% ammonium sulfate, however, the bands were more intense in those from unripe bilimbi. No protein bands were seen in proteases purified with 60% ammonium sulfate. Protein concentration was higher for proteases extracted with 40% ammonium sulfate at both ripening stages. Thus, purification using 40% ammonium sulfate precipitation could be a successful method to partially purify proteases from bilimbi especially from the unripe stage. 

VISUAL DESIGN TOOL FOR ELECTROSTATIC LELSES

2014 ◽  
Vol 5 (2) ◽  
pp. 778-789
Author(s):  
Hassan Nouri Al-Obaidi ◽  
Ali A. Rashead Al-Azawy
Keyword(s):  
Programming Languages ◽  
Electrostatic Potential ◽  
Electric Energy ◽  
Visual Basic ◽  
Visual Programming ◽  
Design Tool ◽  
Mesh Point ◽  
Visual Design ◽  
Computational Tool ◽  
Electrostatic Lenses

Current research presents a visual-computational tool to design and investigate round electrostatic lenses in sense of analysis procedure. The finite elements methods is adopted to find the electrostatic potential in the lens region. Laplace’s equation is first replaced by a certain functional which physically represent the electric energy stored in the electric field. This functional is then minimized at each mesh point with respect to the nearest eight ones. This minimization process is proved to be entirely equivalent to solving Laplace’s equation. The requirement that the functional being minimized is then yields a set of nine point equations which inter relate the potentials at adjacent mesh points. Finally this set of equations is solved to find the electrostatic potential at each mesh point in the region of the lens under consideration. The procedure steps mention above are coded to program written in visual basic. Hence an interface tool for analyzing and designing electrostatic lenses has been built up. Designing results proved that the introduced tools has an excellent outputs in comparison with the others written in not visual programming languages. Furthermore it easier for researchers and designer to use such a tool over their counterpart ones.

Effect of Methionine and Ammonium Sulfate upon Performance of Ruminants Fed High Corn Rations

1973 ◽  
Vol 36 (6) ◽  
pp. 1186-1190 ◽  
Author(s):  
K. K. Bolsen ◽  
Walter Woods ◽  
Terry Klopfenstein
Keyword(s):  
Ammonium Sulfate

Surfactant Impurities Can Explain the Jones-Ray Effect

2018 ◽  
Author(s):  
Timothy Duignan ◽  
Marcel Baer ◽  
Christopher Mundy
Keyword(s):  
Surface Tension ◽  
Electrostatic Potential ◽  
Driving Forces ◽  
Salt Water ◽  
Fundamental Property ◽  
Apparent Contradiction ◽  
Low Salt ◽  
Air Water Interface ◽  
Added Salt ◽  
Effect Of Surface

<div> <p> </p><div> <div> <div> <p>The surface tension of dilute salt water is a fundamental property that is crucial to understanding the complexity of many aqueous phase processes. Small ions are known to be repelled from the air-water surface leading to an increase in the surface tension in accordance with the Gibbs adsorption isotherm. The Jones-Ray effect refers to the observation that at extremely low salt concentration the surface tension decreases in apparent contradiction with thermodynamics. Determining the mechanism that is responsible for this Jones-Ray effect is important for theoretically predicting the distribution of ions near surfaces. Here we show that this surface tension decrease can be explained by surfactant impurities in water that create a substantial negative electrostatic potential at the air-water interface. This potential strongly attracts positive cations in water to the interface lowering the surface tension and thus explaining the signature of the Jones-Ray effect. At higher salt concentrations, this electrostatic potential is screened by the added salt reducing the magnitude of this effect. The effect of surface curvature on this behavior is also examined and the implications for unexplained bubble phenomena is discussed. This work suggests that the purity standards for water may be inadequate and that the interactions between ions with background impurities are important to incorporate into our understanding of the driving forces that give rise to the speciation of ions at interfaces. </p> </div> </div> </div> </div>

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