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关键词： Hydrogels   Mineralisation   Particles   Focal adhesion   Polymers   Hybrid   Colloids   Cells   Nanoparticles   Microparticles  

摘要： Implementation of an effective focal cell adhesion represents a significant challenge, because it requires development of appropriate materials and processes together with assuring that cells would interact with surfaces effectively. Various coatings are under development in the area of biomaterials including hydrogels and polymeric surfaces. Here, we analyse modifications of the coatings by colloidal nanoand micro-particles, which effectively functionalize the surface of soft hydrogel materials, enhance and allow for adjustment of mechanical properties, and enable also release of molecules. An analysis of such hybrid surfaces is presented, where natural and synthetic polymeric coatings are overviewed. These organic coatings are modified by inorganic microand nanoparticles. Various approaches to the design of such hybrid coatings are overviewed with an emphasis on colloid-functionalized surfaces, while additional functionalities such as release of encapsulated biomolecules and enhancement of mechanical properties are highlighted. The developments in this area target effective cell growth, which is shown to be enhanced by the addition of colloidal particles.

关键词： Ionic liquid   Quaternary-ammonium-salt   Gemini ionic liquid   Adsorption   Solution properties  

摘要： Quaternary-ammonium-salt-type amphiphilic gemini compounds 2C(n)(Spacer) NTf2 were synthesized by the quaternization of a tertiary diamine and an n-alkyl bromide, followed by an ion-exchange reaction with potassium bis(trifluoromethanesulfonyl)imide [(Spacer) = (2-O-2), (2-O-2-O-2), (2-N-2), (2/2-N-2), (2/2)-OH, (5), (6), and n represents the alkyl chain lengths;n = 10, 12, 14 for the 2-O-2 spacer, and n = 12 for all others]. The compounds with melting points below 100 degrees C were treated as ionic liquids during the subsequent measurements. The melting points of the amphiphilic gemini compounds could be arranged in the following order, based on the spacer present: (2/2)-OH > 2/2-N-2 > (2-N-2) > (2-O-2) > (5) > (6) > (2-O-2-O-2). The melting points for 2C(n)(2-O-2) NTf2 (n = 10, 12), 2C(12)(2-O-2-O-2) NTf2, and 2C(12)(2-N-2) NTf2 could be reduced to < 0 degrees C. The amphiphilic gemini ionic liquids exhibited significantly lower conductivities and higher viscosities than the corresponding monomeric ionic liquids. This was attributed to a decrease in the mobility of the cationic molecules caused by the gemini structure, in which the two monomeric compounds are connected by a spacer. Furthermore, the amphiphilic gemini ionic liquids, particularly those containing oxygen in the spacer, exhibited efficient adsorption at the air/water interface.

关键词： Physicochemical parameters   Water quality index   Data assimilation   Ensemble Kalman filter   Intrinsic time-scale decomposition  

摘要： Water quality has a crucial impact on human health;therefore, water quality index modeling is one of the challenging issues in the water sector. The accurate prediction of water quality index is an essential requisite for water quality management, human health, public consumption, and domestic uses. A comprehensive review as an initial attempt is conducted on existing solutions through data-driven models. In addition, the ensemble Kalman filter is found to be a suitable data assimilation method, which is successfully applied in hydrological variables modeling and other complexes, nonlinear, and chaotic problems. In this study, a new application of ensemble Kalman filter-artificial neural network is proposed to predict water quality index using physicochemical parameters for two commonly pollutant rivers, namely Klang and Langat, in Malaysia. As a further attempt, in order to improve the models' performance, a new preprocessing technique is adopted as the newly constructed assimilated model. The results confirm that ensemble hybrid based intrinsic time-scale decomposition has reduced root mean square error by 24% for Klang and 34% for Langat, respectively, compared with the intrinsic time-scale decomposition-conventional neural network model. Overall, the developed assimilated methodology shows the robustness of the proposed ensemble hybrid model in analyzing water quality index over monthly horizons that experts could evaluate the water quality of rivers more efficiently. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Fish burger   silver carp   poultry meat   texture   SDS-PAGE  

摘要： This study was focused on the development of fish burgers incorporated with different types of minced meat. For this purpose, silver carp minced meat was mixed with various ratios (25%, 50%, and 75%) of shrimp, camel, and ostrich minced meats. Then, physicochemical properties and sensory quality of produced burgers were evaluated. From the results, fish burgers with 75% ostrich meat had the highest content of protein (22.47%) compared to other treatments (P< .05). The highest and lowest myoglobin contents were found in the burgers with 75% ostrich meat and 75% shrimp meat, respectively (P< .05). Fish burgers with 75% shrimp meat had the highest cholesterol content (84.36 mg/100 g) among all prototypes (P< .05). SDS-PAGE analysis showed that the fish burgers with 75% camel meat had the highest levels of myosin heavy chain (43.53%) and alpha-actinin (6.65%). Textural characteristics and sensory attributes were improved in the fish burgers with 75% ostrich meat. In conclusion, mixing 75% ostrich meat with 25% minced fish could improve some quality parameters of the final product.

关键词： Exopolysaccharides   Antioxidant polysaccharides   Functional roles  

摘要： An exopolysaccharide (EPS) producer slimy-mucoid type colony was isolated from sourdough and identified as Weissella ciboria MED17. The H-1 and C-13 NMR spectra of EPS MED17 demonstrated that this EPS was a dextran type glucan ((1 -> 6)-linked alpha-D-glucose core structure) containing (1 -> 3)-linked alpha-D-glucose branches and proportion of (1 -> 6)-linked alpha-D-glucose units to (1 -> 3)-linked alpha-D-glucose units was 943:5.7%. The MR analysis also confirmed the (1 -> 6)-linked alpha-D-glucose linkage. A high level of thermal stability was observed for glucan MED17 as no degradation up to 300 degrees C was observed by TGA and DSC analysis. The XRD analysis of glucan MED17 showed its semi- crystalline nature and its compact sheet-like morphology was observed by SEM analysis. Finally, antioxidant characteristics of glucan MED17 were determined by ABTS and DPPH radical scavenging activity tests that revealed a moderate antioxidant activity of glucan MED17. These findings show potential techno-functional characteristics of glucan MED17. (C) 2020 Elsevier B.V. All rights reserved.

摘要： The quality of an ophthalmic suspension is crucial for its in vivo performance, and often impact product's effectiveness. An in-depth understanding of critical quality attributes (CQAs) of ophthalmic suspensions such as particle size distribution (PSD) and rheology, as well as the impact of these CQAs on product performance are important for successful product development, quality control, and regulatory approval. This study employed brinzolamide ophthalmic suspension, 1%, as a model ophthalmic product, and six batches were manufactured using an innovative planetary centrifugal milling (PCM) process. Three batches were manufactured to have distinctly different PSD. These three batches had qualitatively (Q1) and quantitatively (Q2) the same composition as the model drug product (i.e., Azopt), while the differences in PSD were introduced by changing only the manufacturing process parameters. On the other hand, changes in rheology were introduced by altering the input level of the viscosity enhancing polymer in the formulation. A systematic approach was employed to understand the relation between manufacturing process parameters, CQAs, and in vitro product performance. Among the evaluated CQAs, PSD, rheology, surface tension, and drug dissolution were found more sensitive to the changes in the manufacturing processes. Most notably, we developed a rapid dissolution method (completed within minutes) employing in-situ fiber optic UV dissolution system. This novel dissolution method mimics the environmental conditions of the eye such as dissolution under "non-sink" condition and under high shear (from blinking). The method was highly discriminatory to differences in the PSD in the suspension. This study also revealed an important relation between the PSD of the suspension and its rheology which originated as a result of an interaction at the molecular level between the solid drug particles and the viscosity enhancing polymers. These findings underscore the need to evaluate

关键词： Condensed tannin   Proanthocyanidin   Hydroxyalkylation   Bio-based polyol   Polyurethane foams   Thermal stability  

摘要： Renewable, bio-based and functional polyols are increasingly being sought as precursors for polyurethanes. A hydroxybutylated Pinus radiata bark tannin (HBBT) was prepared via a mild-base solvent-free synthesis and used as a polyol source in rigid polyurethane foams prepared in conjunction with commercial sorbitol or sucrose-based polyols. The resulting foams were physically and chemically characterised using FTIR spectroscopy, SEM, mechanical compression testing and thermogravimetric analysis. Addition of HBBT had minimal impact on the foam density, however the cellular structure became increasingly deformed at higher substitution levels. The specific modulus and strength increased with HBBT addition, by up to 50% at higher HBBT loadings. Thermal stability was improved through HBBT addition, increasing the degradation onset temperature, reducing mass loss at high temperature and providing higher char residuals. These findings indicate the potential to use HBBT in polyurethane foams for the building and construction industries, offering both improved mechanical properties and increased thermal resistance.

关键词： Babassu   Biolubricant   Trimethylolpropane   NH-10   TG-FTIR  

摘要： In the search of new bioproducts, which could substitute petroleum derivatives and with capability to attend industrial demand, the present research reports the synthesis of babassu-oil-based biolubricant (Orbignya speciosa M), its characterization, and the impact in mineral lubricant properties when the biolubricant was used as additive. The botanical species was submitted to chromatographic analysis, and the oil content was predominantly saturated. Spectroscopy analysis confirmed the success of the reaction, and the biolubricant consisted of a mixture of mono, di and tri esters of trimethylolpropane. The thermogravimetric behavior of the babassu biolubricant was also studied. The gaseous products evolved during the process were analyzed by infrared spectroscopy and the volatilization and combustion process could be described. Blends between babassu biolubricant and mineral basic oil NH-10 were prepared in the proportions of 3, 5 and 10 % v/v, and physicochemical properties as specific mass, kinematic viscosity at 40 and 100 degrees C, and flow point were evaluated. For the proportions used in the evaluation, babassu biolubricant could be pointed as a secure additive for mineral oil lubricant NH-10. The characterization of babassu biolubricant, the thermogravimetric behavior, and spectroscopy analysis of the gaseous products evolved, as well as the use as a possible additive and points to a possible use for biolubricants.

关键词： Carbon fiber reinforced polymer   Atmospheric pressure plasma treatment   Surface physicochemical properties   Interfacial bonding strength  

摘要： To study the effect of surface physicochemical properties of carbon fiber reinforced polymer (CFRP) on its interfacial bonding strength with adhesive, atmospheric pressure plasma treatment (APPT) using three gases (i. e., argon (Ar), nitrogen (N-2) and air (Air)) was conducted on surfaces of CFRP substrates. Atomic force microscope (AFM) observation indicates that APPT only changes the surface morphology of CFRP in a depth of tens of nanometers, and this minor change contributes little to the interfacial bonding strength of CFRP joints. X-ray photo electron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analyses reveal that the release agent (mainly the -Si-CH3 group) and other contaminations on CFRP substrate surfaces were effectively removed by APPT, which improves the shear strength of CFRP joints from 8.6 MPa to 23.1 MPa. In addition, polar chemical functional groups (i.e., -NH2, -OH, -COOH) were generated on the CFRP substrate surfaces after APPT when nitrogen and air were used as plasma gases, which not only enhances the surface free energy of CFRP substrate but also combines with adhesive molecules through the form of hydrogen bonds and covalent bonds. With this mechanism, the shear strength of CFRP joints increased further to 28.7 MPa and 31.5 MPa when nitrogen and air were used as the plasma gases, respectively. After a quantitative study, the interfacial bonding strength between CFRP substrate and adhesive is expressed as a function of the concentration of -Si-CH3, -NH2 and -OH groups.

关键词： Mass spectrometry  

摘要： Ampicillin: acetylacetone Schiff base (HAA) and its complexes with Co(II), Ni(II), Cu(II), Eu(III) and Gd(III) obtained in pure form. The obtained compounds characterized by CHNM%, FTIR, UV–Vis, Fluorescence, 1HNMR, Mass spectra, DTA, TGA, Magnetic susceptibility, X-ray, AAS, melting point, solubility in different solvents and the conductivity of 0.001 M in DMSO. The obtained data indicate the formation of the target complexes in the form [Co(AA)(H2O)2]NO3.2H2O, [Ni(AA)(H2O)2]Cl.4H2O, [Cu(AA)]Cl.2.5H2O, [Eu(AA)(H2O)Cl]Cl.6H2O and [Gd(AA)(H2O)(NO3)]NO3.2H2O. Co and Ni gave Oh structure while Cu gave square planar form. The Crystal field parameters calculated and discussed for the target complexes. Molecular modelling, molecular mechanics and DFT calculation carried out to the synthesized compounds. The x-ray analysis indicates the nanoparticle behaviour for the Cu-AA complex with an orthorhombic structure. The interactions of the synthesized complexes with DNA moiety investigated with means of spectrometric titration (UV–vis. spectra) and by using fluorescence spectroscopy. Antimicrobial activities of the synthesized compounds screened using the disc diffusion method. HAA and Cu-AA gave activity exceeded the Ampicillin. The docking work carried using the targeting protein of Escherichia coli FabH (PDB code: 1HNJ). The obtained binding energy compared and discussed in terms of the in vitro studies. © 2020