scholarly journals Spatially and Reversibly Actuating Soft Gel Structure by Harnessing Multimode Elastic Instabilities

2021 ◽  
Author(s):  
Yingzhi Liu ◽  
Ansu Sun ◽  
Sreepathy Sridhar ◽  
Zhenghong Li ◽  
Zhuofan Qin ◽  
...  
Keyword(s):  
Gel Structure ◽  
Elastic Instabilities

scholarly journals Impact of the Simulated Gastric Digestion Methodology on the In Vitro Intestinal Proteolysis and Lipolysis of Emulsion Gels

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 321
Author(s):  
Camila Mella ◽  
Michelle Quilaqueo ◽  
Rommy N. Zúñiga ◽  
Elizabeth Troncoso
Keyword(s):  
Heat Treatment ◽  
Protein Isolate ◽  
Gastric Digestion ◽  
Human Gastrointestinal Tract ◽  
Gel Structure ◽  
Intestinal Digestion ◽  
Food Digestion ◽  
The Impact ◽  
Digestion Methods

The aim of this work was to study the impact of the methodology of in vitro gastric digestion (i.e., in terms of motility exerted and presence of gastric emptying) and gel structure on the degree of intestinal proteolysis and lipolysis of emulsion gels stabilized by whey protein isolate. Emulsions were prepared at pH 4.0 and 7.0 using two homogenization pressures (500 and 1000 bar) and then the emulsions were gelled by heat treatment. These gels were characterized in terms of texture analysis, and then were subjected to one of the following gastric digestion methods: in vitro mechanical gastric system (IMGS) or in vitro gastric digestion in a stirred beaker (SBg). After gastric digestion, the samples were subjected to in vitro intestinal digestion in a stirred beaker (SBi). Hardness, cohesiveness, and chewiness were significantly higher in gels at pH 7.0. The degree of proteolysis was higher in samples digested by IMGS–SBi (7–21%) than SBg–SBi (3–5%), regardless of the gel’s pH. For SBg–SBi, the degree of proteolysis was not affected by pH, but when operating the IMGS, higher hydrolysis values were obtained for gels at pH 7.0 (15–21%) than pH 4.0 (7–13%). Additionally, the percentage of free fatty acids (%FFA) released was reduced by 47.9% in samples digested in the IMGS–SBi. For the methodology SBg–SBi, the %FFA was not affected by the pH, but in the IMGS, higher values were obtained for gels at pH 4.0 (28–30%) than pH 7.0 (15–19%). Our findings demonstrate the importance of choosing representative methods to simulate food digestion in the human gastrointestinal tract and their subsequent impact on nutrient bioaccessibility.

scholarly journals Stabilization of purely elastic instabilities in cross-slot geometries

2021 ◽  
Vol 922 ◽  
Author(s):  
Mahdi Davoodi ◽  
Gemma Houston ◽  
Jenna Downie ◽  
Mónica S. N. Oliveira ◽  
Robert J. Poole
Keyword(s):  
Elastic Instabilities

Abstract

scholarly journals Auxeticity in Metals and Periodic Metallic Porous Structures Induced by Elastic Instabilities (Phys. Status Solidi B 1/2019)

2019 ◽  
Vol 256 (1) ◽  
pp. 1970010 ◽  
Author(s):  
Duc Tam Ho ◽  
Cao Thang Nguyen ◽  
Soon-Yong Kwon ◽  
Sung Youb Kim
Keyword(s):  
Porous Structures ◽  
Elastic Instabilities

A gel-membrane model of glomerular charge and size selectivity in series

2001 ◽  
Vol 280 (3) ◽  
pp. F396-F405 ◽  
Author(s):  
Maria Ohlson ◽  
Jenny Sörensson ◽  
Börje Haraldsson
Keyword(s):  
Negative Charge ◽  
Careful Analysis ◽  
Size Selectivity ◽  
Gel Structure ◽  
Experimental Conditions ◽  
Ion Interactions ◽  
In Series ◽  
A Charge ◽  
Glomerular Barrier

We have analyzed glomerular sieving data from humans, rats in vivo, and from isolated perfused rat kidneys (IPK) and present a unifying hypothesis that seems to resolve most of the conflicting results that exist in the literature. Particularly important are the data obtained in the cooled IPK, because they allow a variety of experimental conditions for careful analysis of the glomerular barrier; conditions that never can be obtained in vivo. The data strongly support the classic concept of a negative charge barrier, but separate components seem to be responsible for charge and size selectivity. The new model is composed of a dynamic gel and a more static membrane layer. First, the charged gel structure close to the blood compartment has a charge density of 35–45 meq/l, reducing the concentration of albumin to 5–10% of that in plasma, due to ion-ion interactions. Second, the size-selective structure has numerous functional small pores (radius 45–50 Å) and far less frequent large pores (radius 75–115 Å), the latter accounting for 1% of the total hydraulic conductance. Both structures are required for the maintenance of an intact glomerular barrier.

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