SOLVENT INDUCED CHANGES IN THE CONFORMATIONAL STATE OF β-LACTOGLOBULIN AND THE INFLUENCE OF PROTIC IONIC LIQUIDS

2013 ◽  
Vol 01 (01) ◽  
pp. 1250004 ◽  
Author(s):  
NOLENE BYRNE ◽  
COLIN BARROW ◽  
ADAM MCCLUSKEY
Keyword(s):  
Ionic Liquids ◽  
High Water ◽  
High Water Content ◽  
Native Conformation ◽  
Protic Ionic Liquids ◽  
Triethylammonium Acetate ◽  
Amyloid Fibril Formation ◽  
The Stability ◽  
Induced Changes ◽  
Β Lactoglobulin

The protic ionic liquids (pILs), triethylammonium acetate, triethylammonium trifluoroacetate, triethylammonium mesylate and trimethylammonium sulfate were used to induce various native and non-native conformational states of the protein β-lactoglobulin (βLG). Changes in the secondary structure of βLG were observed on moving from a high water content to a high pIL content. We examined the stability of various pIL induced states via thermal unfolding and refolding, where it was found that at a given pIL concentration a highly stable non-native conformation was formed. The βLG non-native conformation was characterized by a high α-helical content. Additionally, pIL conditions that promoted amyloid fibril formation were identified and characterized by CD, a Thioflavin T binding assay and transmission electron microscopy (TEM). This work highlights the use of pILs as solvents in the study of protein folding using βLG as a model system.

scholarly journals Stability of cactus-pear powder during storage

2016 ◽  
Vol 20 (2) ◽  
pp. 169-173
Author(s):  
Plúvia O. Galdino ◽  
Rossana M. F. de Figueirêdo ◽  
Alexandre J. de M. Queiroz ◽  
Pablícia O. Galdino ◽  
Tâmila K. da S. Fernandes
Keyword(s):  
Water Content ◽  
Water Activity ◽  
Reducing Sugars ◽  
Titratable Acidity ◽  
High Water ◽  
Soluble Solids ◽  
High Water Content ◽  
Cactus Pear ◽  
Total Titratable Acidity ◽  
The Stability

ABSTRACT The stability of cactus-pear powder, obtained by the process of spray drying for 40 days, was evaluated under controlled conditions of relative air humidity (83%) and temperature (25 and 40 °C). The whole pulp was characterized with regard to its physico-chemical parameters: pH, total titratable acidity, soluble solids, water content, total solids, ashes, reducing sugars, total sugars, non-reducing sugars, luminosity, redness, yellowness and water activity. The stored samples in powder were evaluated every 10 days for water content, water activity, total titratable acidity and color (luminosity, redness and yellowness). The whole pulp was slightly acidic and perishable, due to the high water content. During storage, the packages did not prevent water absorption, thus increasing water content and, consequently, water activity. Yellowness oscillated along the storage time, but the predominance of the yellow color was not affected.

A Discussion of the Stability of Foundation Pit or Slope with Soft Interlayer or with Back Berm

2014 ◽  
Vol 1065-1069 ◽  
pp. 96-99
Author(s):  
Hai Ying Hu ◽  
Xiao Wen Zhou ◽  
Zhi Xing Huang
Keyword(s):  
Bearing Capacity ◽  
Soft Soil ◽  
High Water ◽  
High Water Content ◽  
Sliding Surface ◽  
Foundation Pit ◽  
Soft Interlayer ◽  
The Difference ◽  
The Stability ◽  
Slice Method

The soft soil in Pearl River Delta regions is characterized with high water content, high compressibility and low bearing capacity. Therefore, when building the structures on such foundation, it’s necessary to pay attention to the deformation and stability. The projects' practice shows that, when analyzing the stability on foundation pit or slope with soft interlayer, it should not only calculate the overall stability of the slope, but also calculate the stability or bearing capacity of the foundation. Although sometimes the stability of the slope meets the requirements, it doesn’t means that the bearing capacity of the foundation meets the requirements because of the existence soft interlayer, the limitations of the circle slice method and the difference between the sliding surface and the actual sliding surface.

The Dusty Creek landslide on Mount Cayley, British Columbia

1982 ◽  
Vol 19 (3) ◽  
pp. 524-539 ◽  
Author(s):  
J. J. Clague ◽  
J. G. Souther
Keyword(s):  
British Columbia ◽  
Debris Flows ◽  
Maximum Velocity ◽  
High Water ◽  
High Water Content ◽  
Contributing Factors ◽  
Coast Mountains ◽  
Basement Rocks ◽  
Debris Dams ◽  
The Stability

A large (ca. 5 × 106 m3) landslide occurred on the west flank of Mount Cayley in the southern Coast Mountains of British Columbia in 1963. Failure commenced when a large block of poorly consolidated tuff breccia and columnar-jointed dacite was detached from the subvolcanic basement and slid into the valley of Dusty Creek, a small tributary of Turbid Creek. As the detached block accelerated, it quickly fragmented into an aggregate consisting of angular clasts up to several metres across, partially supported by a matrix of fine comminuted rock material. The landslide debris moved about 1 km down Dusty Creek as a wedge-shaped mass up to 70 m thick, banking up on turns and attaining a maximum velocity of 15–20 m/s. The debris mass thinned as it spread across the broader, flatter valley of Turbid Creek, and was deposited as an irregular blanket with a maximum thickness of 65 m along a 1 km length of this valley. As a result of the landslide, Turbid and Dusty Creeks were blocked, and lakes formed behind the debris. These debris dams were soon overtopped and rapidly breached, causing floods and probably debris flows to sweep down Turbid Creek valley far beyond the terminus of the landslide.From an analysis of the annual rings of slide-damaged trees, it is concluded that the landslide probably occurred in July 1963. Although the largest earthquake of 1963 and a moderately intense rainstorm also occurred during this month, there were much larger earthquakes and storms in this area on many previous occasions, and these did not cause large slope failures. Thus, it appears that the stability of the slope at the head of Dusty Creek gradually deteriorated over a long period of time until a relatively minor event, such as a small earthquake or storm, triggered the failure.The main contributing factors to this landslide are geologic and include the presence of: (1) hydrothermally altered faults and fractures in poorly lithified pyroclastic rocks and in jointed volcanic flows; (2) an outward-sloping unconformity separating the Quaternary volcanic sequence from older basement rocks; and (3) fractured glassy selvages surrounding small intrusions in the base of the volcanic pile.Deposits of one or more landslides that predate the 1963 event also occur in Turbid Creek valley. These older deposits are present over a much larger area than the 1963 slide deposits and probably were emplaced by highly mobile debris flows with high water content.

scholarly journals Field Treatment of Storage Sludge and Stability Analysis of Overlying Municipal Waste Landfilling

2021 ◽  
Vol 11 (24) ◽  
pp. 12102
Author(s):  
Kaixi An ◽  
Duanyang Zhuang ◽  
Weian Lin ◽  
Albert Argilaga ◽  
Yunmin Chen ◽  
...  
Keyword(s):  
Stability Analysis ◽  
Water Content ◽  
Limit Equilibrium ◽  
High Sensitivity ◽  
High Water ◽  
Treatment Method ◽  
Strength Properties ◽  
High Water Content ◽  
Critical Surface ◽  
The Stability

Storage sludge has high water content and low shear strength, which limits the capacity expansion of overlying municipal landfilling. Few studies have addressed the field treatment of large amounts of storage sludge due to the variability of the depth of geotechnical property. This paper proposes a stratified treatment method for storage sludge, based on the in situ characterization of layered sedimentary patterns of the storage sludge acquired from the Qizishan landfill in China. Additionally, the stability of the landfilling above the sludge pond is analyzed using the Morgenstern–Price and limit equilibrium slice method, which considers the layered strength properties of solidified sludge. The treated sludge has a significant decrease in average water content from 1398% to 88% and an increase in average cohesion to 23.52 kPa. The high content of clay particles, low amount of solidification products, and high water content together result in the high sensitivity to the water content of the strength of deep solidified sludge. For a 40-m high waste body, stability analysis suggests a sliding surface across the raw sludge pond, while the critical surface remains outside the treated sludge pond and the safety factor is increased from 0.934 to 1.464. The validated stratified treatment provides valuable references for the treatment of deep sludge.

scholarly journals Peptides in the presence of aqueous ionic liquids: tunable co-solutes as denaturants or protectants?

2015 ◽  
Vol 17 (39) ◽  
pp. 26049-26053 ◽  
Author(s):  
Volker Lesch ◽  
Andreas Heuer ◽  
Vasileios A. Tatsis ◽  
Christian Holm ◽  
Jens Smiatek
Keyword(s):  
Molecular Dynamics ◽  
Ionic Liquids ◽  
Molecular Dynamics Simulations ◽  
Acetate Solution ◽  
Native Conformation ◽  
The Stability ◽  
Dynamics Simulations ◽  
Significant Structure

We studied the stability of a small β-hairpin peptide under the influence of an aqueous 1-ethyl-3-methylimidazolium acetate solution via all-atom molecular dynamics simulations. A significant structure dependent binding of ACE to the peptide was identified as the main reason for the denaturation of the native conformation.

scholarly journals Development of Water-in-Oil Emulsions as Delivery Vehicles and Testing with a Natural Antimicrobial Extract

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2105
Author(s):  
Giovana Colucci ◽  
Arantzazu Santamaria-Echart ◽  
Samara C. Silva ◽  
Isabel P. M. Fernandes ◽  
Caroline C. Sipoli ◽  
...  
Keyword(s):  
Tween 80 ◽  
High Water ◽  
High Water Content ◽  
Cinnamon Extract ◽  
Fluid Systems ◽  
Natural Oil ◽  
Span 80 ◽  
Oil Emulsions ◽  
The Stability ◽  
The One

Water-in-oil (W/O) emulsions have high potential for several industrial areas as delivery systems of hydrophilic compounds. In general, they are less studied than oil-in-water (O/W) systems, namely in what concerns the so-called fluid systems, partly due to problems of instability. In this context, this work aimed to produce stable W/O emulsions from a natural oil, sweet almond oil, to be further tested as vehicles of natural hydrophilic extracts, here exemplified with an aqueous cinnamon extract. Firstly, a base W/O emulsion using a high-water content (40/60, v/v) was developed by testing different mixtures of emulsifiers, namely Tween 80 combined with Span 80 or Span 85 at different contents. Among the tested systems, the one using a 54/46 (v/v) Span 80/Tween 80 mixture, and subjected to 12 high-pressure homogenizer (HPH) cycles, revealed to be stable up to 6 months, being chosen for the subsequent functionalization tests with cinnamon extract (1.25–5%; w/v; water-basis). The presence of cinnamon extract leaded to changes in the microstructure as well as in the stability. The antimicrobial and antioxidant analysis were evidenced, and a sustained behavior compatible with an extract distribution within the two phases, oil and water, in particular for the higher extract concentration, was observed.

Rapid Consolidation Behavior of Dredged Clays at High Water Content

2011 ◽  
Vol 368-373 ◽  
pp. 2966-2970
Author(s):  
Yu Peng Cao ◽  
Jian Wen Ding ◽  
Xia Bian ◽  
Feng Ji ◽  
Gui Zhong Xu
Keyword(s):  
Large Scale ◽  
High Water ◽  
Laboratory Model ◽  
High Water Content ◽  
Vertical Drains ◽  
Drainage Rate ◽  
Horizontal Drains ◽  
The Stability ◽  
Stability Time ◽  
Consolidation Behavior

Consolidation of dredged clays with a system of horizontal and vertical drains is considered. Horizontal drains in the system are made of sand layers, while vertical drains are plastic vertical drains (PVD). Laboratory model tests are performed to study the rapid consolidation behavior of layered clay-sand and clay with PVD. Special cares are given to settlement and the drainage rate of dredged clays with radial and vertical drain system. Numerical analysis is also used to identify the stability time of consolidation, and to verify which method is better suitable for handling large-scale dredged clays.

scholarly journals Strength and Leaching Behavior of Contaminated Mining Sludge at High Water Content Stabilized with Lime Activated GGBS

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6524
Author(s):  
Traore Abdoul Fatah ◽  
Rongjun Zhang ◽  
Xiaosong Huang ◽  
Junjie Zheng ◽  
Yu Miao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Water Content ◽  
Experimental Tests ◽  
High Water ◽  
Aluminum Silicate ◽  
High Water Content ◽  
Strength Development ◽  
Efficient Technology ◽  
The Stability ◽  
Mining Sludge

Sludge management is one of the major challenges in mining activities. The direct disposal of contaminated mining sludge can bring severe damages to the environment and community. Solidification/stabilization (S/S) is a very efficient technology for the treatment of contaminated mining sludge because it improves the stability of sludge dumping sites and reduces the leachability of contaminants. Very few studies investigate the S/S of mining sludge, especially with high water content. This paper investigated the effectiveness of S/S for the treatment of mining sludge at high water content by using quick lime (CaO) activated ground granulated blast furnace slag (GGBS) in comparison to ordinary Portland cement (OPC). To evaluate the mechanical, leaching, and microstructural behavior of CMS at high water content stabilized by lime-activated GGBS and OPC, a series of laboratory experimental tests were performed. Experimental results indicated that increasing the dosage of binder led to increased strength and decreased leachability of the heavy metal. In contrast, an increase in the water content of the mixture resulted in a decrease in compressive strength and an increase in the leachability of heavy metals. On the other hand, lime-activated GGBS mixes had substantially better performance than OPC mixes in the aspect of strength development of treated mining sludge and showed comparable capability of heavy metal stabilization compared to OPC. The microstructural tests revealed the formation of different hydration products such as calcium silicate hydrate, calcium aluminum silicate hydrate, ettringite, hydrotalcite, and heavy metal complexes in CG and OPC mixes.

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