scholarly journals Quercetin Induces Lipid Domain-Dependent Permeability

2021 ◽  
Author(s):  
Natalia Slade ◽  
Danubia Batista Martins ◽  
Marcia P. dos Santos Cabrera
Keyword(s):  
Liquid Phase ◽  
Membrane Permeability ◽  
Model Membranes ◽  
The Other ◽  
Lipid Domains ◽  
Lipid Domain ◽  
Homogeneous Systems ◽  
Membrane Rigidity ◽  
Increase Membrane Permeability ◽  
Shape And Size

In this work, we present our results on quercetin interaction with distinct model membranes exploring the importance of lipid phases, ld, ld/lo and ld+lo+so, to the action of this flavonoid in bilayers and possibly contributing to clarifying some controversial aspects related to quercetin multiple activities. We found out that quercetin is able to increase membrane permeability in a manner dependent on the presence and characteristics of lipid domains. In the presence of sphingomyelin, we found the greatest increase in mean membrane permeability (at least 10 times higher than the other lipid compositions). We also observed the presence of micrometric domains whose shape and size were disturbed by the action of quercetin. The presence of cholesterol increased membrane rigidity. This effect was enhanced with the presence of quercetin, but for chol-sphingomyelin combination, the bilayers became more flaccid at low quercetin/lipid proportions (< 1/5) and moderately rigid at proportions of the 1/1 order. The affinity parameters were higher for the most homogeneous systems and with larger areas and extensions of disordered liquid phase than for those systems of higher heterogeneity.

scholarly journals Quercetin Induces Lipid Domain-Dependent Permeability

2021 ◽  
Author(s):  
Natalia Slade ◽  
Danubia Batista Martins ◽  
Marcia P. dos Santos Cabrera
Keyword(s):  
Liquid Phase ◽  
Membrane Permeability ◽  
Model Membranes ◽  
The Other ◽  
Lipid Domains ◽  
Lipid Domain ◽  
Homogeneous Systems ◽  
Membrane Rigidity ◽  
Increase Membrane Permeability ◽  
Shape And Size

In this work, we present our results on quercetin interaction with distinct model membranes exploring the importance of lipid phases, ld, ld/lo and ld+lo+so, to the action of this flavonoid in bilayers and possibly contributing to clarifying some controversial aspects related to quercetin multiple activities. We found out that quercetin is able to increase membrane permeability in a manner dependent on the presence and characteristics of lipid domains. In the presence of sphingomyelin, we found the greatest increase in mean membrane permeability (at least 10 times higher than the other lipid compositions). We also observed the presence of micrometric domains whose shape and size were disturbed by the action of quercetin. The presence of cholesterol increased membrane rigidity. This effect was enhanced with the presence of quercetin, but for chol-sphingomyelin combination, the bilayers became more flaccid at low quercetin/lipid proportions (< 1/5) and moderately rigid at proportions of the 1/1 order. The affinity parameters were higher for the most homogeneous systems and with larger areas and extensions of disordered liquid phase than for those systems of higher heterogeneity.

scholarly journals Quercetin Induces Lipid Domain-Dependent Permeability

2021 ◽  
Author(s):  
Natalia Slade ◽  
Marcia P. dos Santos Cabrera ◽  
Danubia Batista Martins
Keyword(s):  
Liquid Phase ◽  
Membrane Permeability ◽  
Model Membranes ◽  
The Other ◽  
Lipid Domains ◽  
Lipid Domain ◽  
Homogeneous Systems ◽  
Membrane Rigidity ◽  
Increase Membrane Permeability ◽  
Shape And Size

In this work, we present our results on quercetin interaction with distinct model membranes exploring the importance of lipid phases, ld, ld/lo and ld+lo+so, to the action of this flavonoid in bilayers and possibly contributing to clarifying some controversial aspects related to quercetin multiple activities. We found out that quercetin is able to increase membrane permeability in a manner dependent on the presence and characteristics of lipid domains. In the presence of sphingomyelin, we found the greatest increase in mean membrane permeability (at least 10 times higher than the other lipid compositions). We also observed the presence of micrometric domains whose shape and size were disturbed by the action of quercetin. The presence of cholesterol increased membrane rigidity. This effect was enhanced with the presence of quercetin, but for chol-sphingomyelin combination, the bilayers became more flaccid at low quercetin/lipid proportions (< 1/5) and moderately rigid at proportions of the 1/1 order. The affinity parameters were higher for the most homogeneous systems and with larger areas and extensions of disordered liquid phase than for those systems of higher heterogeneity.

The Alteration of the Pore Spaces in Sandstones

1973 ◽  
Vol 31 ◽  
pp. 210-211
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
The Other ◽  
Coarse Grained ◽  
Depositional Fabric ◽  
Soluble Components ◽  
Scanning Electron ◽  
Shape And Size

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.

The Reactivity of Different Active Forms of Sodium Carbonate with Respect to Sulfur Dioxide

1992 ◽  
Vol 57 (11) ◽  
pp. 2302-2308
Author(s):  
Karel Mocek ◽  
Erich Lippert ◽  
Emerich Erdös
Keyword(s):  
Thermal Decomposition ◽  
Liquid Phase ◽  
Sulfur Dioxide ◽  
Specific Surface ◽  
Surface Area ◽  
Sodium Carbonate ◽  
Room Temperature ◽  
Active Form ◽  
The Other ◽  
Kinetics Of

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.

scholarly journals Grasp to See—Object Classification Using Flexion Glove with Support Vector Machine

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1461
Author(s):  
Shun-Hsin Yu ◽  
Jen-Shuo Chang ◽  
Chia-Hung Dylan Tsai
Keyword(s):  
Support Vector Machine ◽  
Daily Life ◽  
Object Classification ◽  
Target Object ◽  
The Other ◽  
Support Vector ◽  
Wide Range ◽  
Dark Space ◽  
Flex Sensors ◽  
Shape And Size

This paper proposes an object classification method using a flexion glove and machine learning. The classification is performed based on the information obtained from a single grasp on a target object. The flexion glove is developed with five flex sensors mounted on five finger sleeves, and is used for measuring the flexion of individual fingers while grasping an object. Flexion signals are divided into three phases, and they are the phases of picking, holding and releasing, respectively. Grasping features are extracted from the phase of holding for training the support vector machine. Two sets of objects are prepared for the classification test. One is printed-object set and the other is daily-life object set. The printed-object set is for investigating the patterns of grasping with specified shape and size, while the daily-life object set includes nine objects randomly chosen from daily life for demonstrating that the proposed method can be used to identify a wide range of objects. According to the results, the accuracy of the classifications are achieved 95.56% and 88.89% for the sets of printed objects and daily-life objects, respectively. A flexion glove which can perform object classification is successfully developed in this work and is aimed at potential grasp-to-see applications, such as visual impairment aid and recognition in dark space.

Breakthrough of Sublimation Drying by Liquid Phase Deposition

2021 ◽  
Vol 314 ◽  
pp. 172-177
Author(s):  
Yuta Sasaki ◽  
Yousuke Hanawa ◽  
Masayuki Otsuji ◽  
Naozumi Fujiwara ◽  
Masahiko Kato ◽  
...  
Keyword(s):  
Free Energy ◽  
Liquid Phase ◽  
Film Thickness ◽  
Process Parameters ◽  
Interfacial Free Energy ◽  
The Other ◽  
Liquid Phase Deposition ◽  
Drying Method ◽  
Substrate Side ◽  
Drying Technology

Damage-free drying becomes increasingly difficult with the scaling of semiconductor devices. In this work, we studied a new sublimation drying technology for 3nm node and beyond. In order to investigate the collapse factor by conventional sublimation drying, we observed the pattern with cryo-SEM and revealed that the collapse occurred when the liquid film on the substrate solidified. Based on this result, we considered that it was important to deposit a solidified film uniformly from the substrate side to suppress collapse. Two key process parameters were evaluated to achieve the uniform formation of the solidified film. One is interfacial free energy and the other is film thickness of solution just before solidification. By optimizing two key parameters, it was successfully demonstrated to suppress pattern collapse of challenging devices. In this paper, we report on a new drying method: sublimation drying by LPD (Liquid-phase deposition).

A Decade of Development in Immunoassay Methodology

1990 ◽  
Vol 36 (8) ◽  
pp. 1408-1427 ◽  
Author(s):  
James P Gosling
Keyword(s):  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Analytical Methods ◽  
Clinical Laboratory ◽  
Solid Phase ◽  
Detection Limits ◽  
Assay System ◽  
Future Trends ◽  
Homogeneous Systems ◽  
Major Trend

Abstract Immunoassays are now very widely used in the clinical laboratory, either because no other type of assay system is feasible or because they are often the most effective and suitable of the possible analytical methods. The last decade has seen the development and refinement of many new immunoassay reagents and systems. The major trend has been away from liquid-phase assays involving radioisotopic labels, towards fast homogeneous or solid-phase assays capable of operation anywhere; and towards precise and reliable nonisotopic, automated or semi-automated laboratory assays, often with detection limits measured in pico- or attomoles. The use of monoclonal antibodies is now widespread, and the methodologies of labels and of solid-phase components are much more sophisticated. New assay formulations, novel homogeneous systems, immunosensors, free-analyte assays, the importance of thorough validation and of interfering substances, and future trends are discussed.

A new species of Ferula (Apiaceae) from Malta

Phytotaxa ◽  
2018 ◽  
Vol 382 (1) ◽  
pp. 74 ◽  
Author(s):  
SALVATORE BRULLO ◽  
CRISTIAN BRULLO ◽  
SALVATORE CAMBRIA ◽  
GIANPIETRO GIUSSO DEL GALDO ◽  
CRISTINA SALMERI ◽  
...  
Keyword(s):  
New Species ◽  
Close Relationships ◽  
Morphological Analysis ◽  
The Other ◽  
Taxonomic Group ◽  
Herbarium Material ◽  
Reproductive Structures ◽  
Leaf Segments ◽  
A New Species ◽  
Shape And Size

Ferula melitensis, a new species from the Malta Archipelago, is described and illustrated. It belongs to the taxonomic group of F. communis, showing close relationships mainly with F. tunetana, F. arrigonii, F. communis s.str. and F. glauca, from which it differs in several features regarding the stem, leaves (mainly for shape and size of terminal segments), flowers and mericarps; other significant differences regard the ecology and phenology. The investigations, carried out on living plants, herbarium material and literature data, regard the morphological analysis of vegetative and reproductive structures, the anatomy of terminal leaf segments and mericarps, as well as the shape and size of seedlings. Previous phylogenetic approaches, based on nuclear and plastidial genome, have allowed to clarify better the relationships among F. melitensis and the other species of this group.

Sign in / Sign up

Export Citation Format

Share Document