scholarly journals Onion Micelles with an Interpolyelectrolyte Complex Middle Layer: Experimental Motivation and Computer Study

2020 ◽  
Vol 53 (16) ◽  
pp. 6780-6795
Author(s):  
Rahul Kumar Raya ◽  
Miroslav Štěpánek ◽  
Zuzana Limpouchová ◽  
Karel Procházka ◽  
Martin Svoboda ◽  
...  
Keyword(s):  
Middle Layer ◽  
Computer Study ◽  
Interpolyelectrolyte Complex

scholarly journals Solubilization of Charged Porphyrins in Interpolyelectrolyte Complexes: A Computer Study

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 502
Author(s):  
Karel Šindelka ◽  
Zuzana Limpouchová ◽  
Karel Procházka
Keyword(s):  
Dissipative Particle Dynamics ◽  
Water Soluble ◽  
Coarse Grained ◽  
Core Shell ◽  
Computer Study ◽  
Interpolyelectrolyte Complex ◽  
The Core ◽  
Porphyrin Derivatives ◽  
Oppositely Charged ◽  
Positively Charged

Using coarse-grained dissipative particle dynamics (DPD) with explicit electrostatics, we performed (i) an extensive series of simulations of the electrostatic co-assembly of asymmetric oppositely charged copolymers composed of one (either positively or negatively charged) polyelectrolyte (PE) block A and one water-soluble block B and (ii) studied the solubilization of positively charged porphyrin derivatives (P+) in the interpolyelectrolyte complex (IPEC) cores of co-assembled nanoparticles. We studied the stoichiometric mixtures of 137 A10+B25 and 137 A10−B25 chains with moderately hydrophobic A blocks (DPD interaction parameter aAS=35) and hydrophilic B blocks (aBS=25) with 10 to 120 P+ added (aPS=39). The P+ interactions with other components were set to match literature information on their limited solubility and aggregation behavior. The study shows that the moderately soluble P+ molecules easily solubilize in IPEC cores, where they partly replace PE+ and electrostatically crosslink PE− blocks. As the large P+ rings are apt to aggregate, P+ molecules aggregate in IPEC cores. The aggregation, which starts at very low loadings, is promoted by increasing the number of P+ in the mixture. The positively charged copolymers repelled from the central part of IPEC core partially concentrate at the core-shell interface and partially escape into bulk solvent depending on the amount of P+ in the mixture and on their association number, AS. If AS is lower than the ensemble average ⟨AS⟩n, the copolymer chains released from IPEC preferentially concentrate at the core-shell interface, thus increasing AS, which approaches ⟨AS⟩n. If AS>⟨AS⟩n, they escape into the bulk solvent.

Computer study of the solubilization of polymer chains in polyelectrolyte complex cores of polymeric nanoparticles in aqueous media

2018 ◽  
Vol 20 (47) ◽  
pp. 29876-29888 ◽  
Author(s):  
Karel Šindelka ◽  
Zuzana Limpouchová ◽  
Karel Procházka
Keyword(s):  
Computer Simulations ◽  
Polyelectrolyte Complex ◽  
Polymeric Nanoparticles ◽  
Aqueous Media ◽  
Polymer Chains ◽  
Coarse Grained ◽  
Computer Study ◽  
Interpolyelectrolyte Complex ◽  
Structure Of Nanoparticles ◽  
Polar Polymer

The formation and structure of nanoparticles containing non-polar polymer chains solubilized in interpolyelectrolyte complex (IPC) cores and the partitioning of non-polar chains between bulk solvent and IPC cores were studied by coarse-grained computer simulations.

Environmentally Friendly Preparation of Magnetic Composites Featuring Proteolytic Properties

INEOS OPEN ◽  
2020 ◽  
Author(s):  
N. A. Samoilova ◽  
Keyword(s):  
Enzyme Immobilization ◽  
Maleic Acid ◽  
Environmentally Friendly ◽  
Synthetic Polymer ◽  
Magnetic Composites ◽  
Interpolyelectrolyte Complex ◽  
Hydrolysis Rates ◽  
Poly Ethylene ◽  
Noncovalent Binding

The enzyme-containing magnetic composites are presented. The magnetic matrix for enzyme immobilization is obtained by sequential application of an amine-containing polysaccharide—chitosan and a synthetic polymer—poly(ethylene-alt-maleic acid) to the magnetite microparticles to form the interpolyelectrolyte complex shell. Then, the enzyme (trypsin) is immobilized by covalent or noncovalent binding. Thus, the suggested composites can be readily obtained in the environmentally friendly manner. The enzyme capacity of the resulting composites reaches 28.0–32.6 mg/g. The maximum hydrolysis rates of the H-Val-Leu-Lys-pNA substrate provided by these composites range within 0.60·10–7–0.77·10–7 M/min.

Effect of CeO2 Modified MAS Middle Layer on the Joint of C/C-LAS

2013 ◽  
Vol 28 (12) ◽  
pp. 1345-1348
Author(s):  
Huan-Xia ZHU ◽  
Ke-Zhi LI ◽  
Jin-Hua LU ◽  
He-Jun LI ◽  
Jian-Yang WANG
Keyword(s):  
Middle Layer

Improved Environment-Aware–Based Noise Reduction System for Cochlear Implant Users Based on Knowledge Transfer Approach (Preprint)

2020 ◽  
Author(s):  
Lieber Po-Hung Li ◽  
Ji-Yan Han ◽  
Wei-Zhong Zheng ◽  
Ren-Jie Huang ◽  
Ying-Hui Lai
Keyword(s):  
Knowledge Transfer ◽  
Cochlear Implant ◽  
Noise Reduction ◽  
Speech Intelligibility ◽  
Middle Layer ◽  
Successful Implementation ◽  
Perceptual Evaluation ◽  
Reduction System ◽  
Listening Tests ◽  
Implementation Costs

BACKGROUND The cochlear implant technology is a well-known approach to help deaf patients hear speech again. It can improve speech intelligibility in quiet conditions; however, it still has room for improvement in noisy conditions. More recently, it has been proven that deep learning–based noise reduction (NR), such as noise classification and deep denoising autoencoder (NC+DDAE), can benefit the intelligibility performance of patients with cochlear implants compared to classical noise reduction algorithms. OBJECTIVE Following the successful implementation of the NC+DDAE model in our previous study, this study aimed to (1) propose an advanced noise reduction system using knowledge transfer technology, called NC+DDAE_T, (2) examine the proposed NC+DDAE_T noise reduction system using objective evaluations and subjective listening tests, and (3) investigate which layer substitution of the knowledge transfer technology in the NC+DDAE_T noise reduction system provides the best outcome. METHODS The knowledge transfer technology was adopted to reduce the number of parameters of the NC+DDAE_T compared with the NC+DDAE. We investigated which layer should be substituted using short-time objective intelligibility (STOI) and perceptual evaluation of speech quality (PESQ) scores, as well as t-distributed stochastic neighbor embedding to visualize the features in each model layer. Moreover, we enrolled ten cochlear implant users for listening tests to evaluate the benefits of the newly developed NC+DDAE_T. RESULTS The experimental results showed that substituting the middle layer (ie, the second layer in this study) of the noise-independent DDAE (NI-DDAE) model achieved the best performance gain regarding STOI and PESQ scores. Therefore, the parameters of layer three in the NI-DDAE were chosen to be replaced, thereby establishing the NC+DDAE_T. Both objective and listening test results showed that the proposed NC+DDAE_T noise reduction system achieved similar performances compared with the previous NC+DDAE in several noisy test conditions. However, the proposed NC+DDAE_T only needs a quarter of the number of parameters compared to the NC+DDAE. CONCLUSIONS This study demonstrated that knowledge transfer technology can help to reduce the number of parameters in an NC+DDAE while keeping similar performance rates. This suggests that the proposed NC+DDAE_T model may reduce the implementation costs of this noise reduction system and provide more benefits for cochlear implant users.

SIMULATION OF MIDDLE LAYER TURBIDITY PEAK AND BLUE TIDE

2019 ◽  
Vol 75 (2) ◽  
pp. I_997-I_1002
Author(s):  
Teruhisa OKADA ◽  
Masahiro IMAMURA
Keyword(s):  
Middle Layer

scholarly journals WALL STRESS IN ASCENDING AORTA ANEURYSMS AS A PREDICTIVE FACTOR OF BREAKAGE

2021 ◽  
Vol 108 (Supplement_3) ◽  
Author(s):  
R J Burgos Lázaro ◽  
N Burgos Frías ◽  
S Serrano-Fiz García ◽  
V Ospina Mosquera ◽  
F Rojo Pérez ◽  
...  
Keyword(s):  
Aortic Wall ◽  
Wall Stress ◽  
Middle Layer ◽  
Ascending Aorta ◽  
Aortic Aneurysms ◽  
Maximum Diameter ◽  
Resistance Factors ◽  
Risk Of Rupture ◽  
Traction Test

Abstract INTRODUCTION The surgical indication for ascending aortic aneurysms (AAA) is established when the maximum diameter > 50 mm; It responds to Laplace's Law (T wall = P × r / 2e). The aim of the study is to define wall stress in AAA. MATERIAL AND METHODS 218 ascending aortic walls have been studied: 96 from organ donors, and 122 from AAA: Marfán 58 (47.5%), bicuspid aortic valve 26 (21.4%), and atherosclerosis 38 (31.1%). The samples were studied "in vitro", according to the model Young's (relationship between stress and deformed area), by means of the mechanical traction test (Tension = Force / Area). The analysis was performed with the stress-elongation curve (d Tension / d Elongation). RESULTS The stress of the aortic wall, classified from highest to lowest according to pathology and age was: cystic necrosis of the middle layer, arteriosclerosis, age > 60 years, between 35 and 59, and < 34 years. The stress of “control aortas” wall increased directly in relation to the age of the donors. CONCLUSIONS The maximum diameter of the ascending aorta, the patient's type of pathology and age are factors that affect the maximum tension of the aortic wall and resistance, factors that allow differentiation and prediction of the risk of rupture of the AAA. The validation of the results obtained through numerical simulation was significant and the uniaxial analysis has modeled the response of the vessels to their internal pressure.

scholarly journals Kinetics of slow release of nitrogen fertiliser from multi-layered nanofibrous structures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Leila Javazmi ◽  
Anthony Young ◽  
Gavin J. Ash ◽  
Tobias Low
Keyword(s):  
Crop Production ◽  
Slow Release ◽  
New Technology ◽  
Single Layer ◽  
Middle Layer ◽  
Modern Agriculture ◽  
Triple Layer ◽  
Urea Release ◽  
Electrospun Nanofibres ◽  
Kinetics Of

AbstractFertilisers are essential in modern agriculture to enhance plant growth, crop production and product quality. Recent research has focused on the development of delivery systems designed to prolong fertiliser release. This study introduces a new technology to encapsulate and release molecules of fertilisers by using multi-layered electrospun nanofibre as a carrier. Single-layer poly L-lactic acid (PLLA) nanofibres loaded with urea were fabricated using electrospinning. Triple-layer nanofibrous structures were produced by electrospinning polyhydroxybutyrate (PHB) nanofibres as external layers with PLLA nanofibres impregnated with urea fertiliser as the middle layer. Scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometry (FTIR) were employed to characterize the morphology of electrospun nanofibres. Urea release dynamic was analysed using a total nitrogen instrument (TNM-1). The results indicated that triple-layered urea-impregnated nanofibrous structures led to lower initial rate of nitrogen release and slower release rate of cumulative nitrogen which extended for more than three months. It is concluded that triple-layer nanofibrous structures have the potential for slow release delivery of fertilisers.

Synthesis of xanthan gum/trimethyl chitosan interpolyelectrolyte complex as pH-sensitive protein carrier

2021 ◽  
Author(s):  
Mahmoud H. Abu Elella ◽  
Demiana H. Hanna ◽  
Riham R. Mohamed ◽  
Magdy W. Sabaa
Keyword(s):  
Xanthan Gum ◽  
Ph Sensitive ◽  
Interpolyelectrolyte Complex ◽  
Protein Carrier ◽  
Trimethyl Chitosan
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