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关键词： C(3)A   C3S   hydration   nanosilica   retardation  

摘要： In this paper, C(3)A-gypsum and C(3)A-C3S-gypsum model cement systems with and without nanosilica were studied. The effects of nanosilica on the early stage cement hydration, particularly C(3)A hydration, were assessed through the heat of hydration (isothermal calorimetry), phase assemblage (quantitative X-ray diffraction), zeta potential, ion concentration measurements, and morphology (scanning electron microscopy) examinations. The results indicate that while promoting C3S hydration, nanosilica retarded C(3)A hydration in both the systems studied. The retardation was caused by the adsorption and coverage of nanosilica on C(3)A surfaces through the electrostatic interaction, thus decreasing the C(3)A dissolution rate and hindering the precipitation of hydration products. Consequently, the reduced gypsum consumption rate and the seeding effect of nanosilica further promoted C3S hydration. These findings suggest that nanosilica and other silica-based nanoparticles can physicochemically influence hydration of cement-based materials, and a better understanding of these influencing mechanisms can help optimize performances of nanoparticle-modified cement-based materials.

关键词： Sterilization treatment   Total phenols   Sensory analysis   Electronic tongue  

摘要： The effect of thermal sterilization processes on the physicochemical parameters and sensory characteristics of Californian-style black olives, from 'Hojiblanca' and 'Manzanilla Cacerena' brine solutions, were evaluated. Two-way ANOVA showed that 'Hojiblanca' olives had a lower phenols content and defect intensity and that increasing the sterilization period resulted in a decrease in total phenols and an increase of the cooked defect. The impact of thermal sterilization was further evaluated using a potentiometric electronic tongue, which was capable of discriminating the different sterilization treatments (repeated K-fold cross-validation sensitivity: 89.0 +/- 15.0% to 97.0 +/- 6.0%). Moreover, multiple regressions allowed the prediction of phenols (R-2 >= 0.95 +/- 0.03) and the intensity of the defect (R-2( )>= 0.95 +/- 0.04). These results point out the feasibility of the electronic tongue as an analytical tool for monitoring the effects of thermal sterilization treatments. Furthermore, the satisfactory results obtained for the brine solutions may foresee a practical non-destructive method for indirect quality assessment of table olives.

关键词： UV-C light   Mild heat   Candida parapsilosis   Flow cytometry   Quality assessment   Sensory analysis  

摘要： In the past two decades, novel preservation technologies have been investigatedto achievesufficient microbial reduction while improving thequality of food and beverages. The effect of UV-C light (UV-C, 1720 mJ/cm(2)) assisted by mild heat (H, 50 degrees C) on the inactivation and the physiological state ofCandida parapsilosisATCC 22019 in a carrot-orange juice was studied by flow cytometry. Additionally, the juice samples processed or not (control) by the single (UV-C;H) and combined (UV-C/H) treatments were analyzed for total polyphenol content (TPC), total antioxidant activity (TAA), color, turbidity, degrees Brix, pH, and pectin methylesterase units (PME) along 13-24-day storage (4 degrees C). Consumer-profiling studies were conducted on UV-C/H and a pasteurized juice. UV-C/H was highly effective in reducingC. parapsilosisby 5.5 log cycles, whereas the single UV-C and H treatments induced 2.9 and 3.9 log reductions, respectively. Flow cytometry revealed a shift with time from cells with intact membrane and esterase activity to those with permeabilized membrane and without esterase activity, which was significantly higher for UV-C/H samples (98.0%) compared with the single treatments (12.0-46.2%). UV-C/H preserved juice color, pH, degrees Brix, and turbidity of the juice, which exhibited equal TAA (0.7 mg/mL) and higher TPC (302.1 mu g/mL) than the control (TAA = 0.7 mg/mL/TPC = 205.0 mu g/mL), remaining constant throughout storage. PME decreased 42-45% for the H and UV-C/H treatments, respectively. A cluster sensory analysis revealed that one group of consumers showed a remarkable interest in the UV-C/H juice, while the conjoint study showed that it was perceived as very healthy. The CATA question determined that the UV-C/H processing prevented the juice from being perceived too particulate or with cooked or artificial taste, as happened with the pasteurized juice.

关键词： Alkyl-peptide   Self-assembly   Neural progenitor cell   Coarse-grained molecular dynamics simulation  

摘要： Amphiphilic alkyl-peptides as novel biomaterials form 3D scaffolds that are applicable in tissue engineering. Here, the nanofibre formation capability of a distinct alkyl-peptide was investigated using coarse-grained molecular dynamics simulation (CGMD) and experimental methods. The alkyl-peptide (Ace-FAQRVPPEEEGG-GAAAAK-Nhe(C16)) was functionalized with a peptide epitope (FAQRVPPP) which can help to maintenance and differentiation of neural stem cells. Two alkyl-peptide systems were investigated: the all-functionalized system (with only bioactive alkyl-peptides) and the distributed system (a combination of bioactive and non-bioactive alkyl-peptides with ratio 1:2). The CGMD and TEM results confirm elongated nanofibres for all-functionalized system and cylindrical nanofibres for the distributed one. Furthermore, PC12 cells show a reliable growth on both 2D alkyl-peptides coated surfaces. Because of the nanofibres negative surface charges, the cell morphologies show clustered form in the distributed system and rounded shape in the all-functionalized one. Since the stem cell state preserves in cluster form, the physicochemical property of these nanofibres allows a potential advantage in stem cell long-time maintains.

关键词： Chitosan   PVA   Solanum nigrumL   Biodegradable films  

摘要： In this work, composite films for food packaging were prepared from chitosan (CS) and polyvinyl alcohol (PVA) incorporated with extracts of edibleSolanum nigrumL. (SN) leaves by solvent casting method. The effect of water (SW), ethanol (SE), and methanolic (SM) extracts of SN leaves on the mechanical, physical, barrier, optical, soil degradability, antimicrobial, and antioxidant properties of the films were studied. The composite films have smooth homogeneous surface morphology and showed enhanced UV blocking properties. Incorporation of SN leaves extract greatly enhances the tensile strength. The water vapor transmission rate also improved by the influence of SN extracts. The surface wettability of the composite films significantly (p < 0.005) enhanced. The soil degradability of the film samples was improved by 50%. All the composite films have an overall migration rate within the permitted limit. Besides, the SN leaves incorporated CS/PVA films showed enhanced antibacterial activity towardsStaphylococcus aureusandEscherichia colibacteria and samples did not show significant antifungal activity towards Candida albicans. All SN extracts incorporated samples showed enhanced antioxidant activity by DPPH scavenging assay. These results suggest that all three SN leaves extract induced CS/PVA composite films can be used for food packaging applications.

关键词： Airport runoff   Deicers   Ecotoxicity   Bioassays   Lemna gibba   Aliivibrio fischeri  

摘要： A critical problem derived from airport operations is the environmental impact of runoff water. Airport runoff includes a complex mixture of pollutants, e.g., from deicing agents, that may affect negatively natural water bodies. This study assesses the spatial and temporal aquatic ecotoxicity of runoff water and possible aeroplane drift in a German airport. Over winter 2012-2013, from November to May, water samples were collected within the airport and surrounding area. These samples were analyzed using traditional physicochemical analysis and biotests with two aquatic organisms from different trophic levels,Lemna gibbaandAliivibrio ***, the samples examined in this study were relatively non-toxic to the tested organisms. The physicochemical parameters were mainly influenced by the sampling period being higher in colder months. In contrast, the ecotoxicity was influenced by the sampling site. For sites within the airport, a high correlation between the physicochemical parameters (EC and TOC) and toxicity inL. gibbawas found. These correlations were not evident in samples taken outside the airport or whenA. fischeriwas used as a bioindicator. However, a pronounced seasonality has been observed, linked to the coldest months with average inhibition values of 50% inL. gibbaand 25% inA. fischeri, particularly in January. Both biotests yielded differing results;therefore, more biotests should be included. However,L. gibbashowed a good response with this type of water samples to be included in future studies together with detailed chemical analysis. The present study provides data to assess the potential ecotoxicological effects of airport runoff affected by winter operations.

关键词： albendazole   polyurethane   nanoparticles   cell viability  

摘要： Albendazole is a benzimidazole derivative with documented antitumor activity and low toxicity to healthy cells. The major disadvantage in terms of clinical use is its low aqueous solubility which limits its bioavailability. Albendazole was incorporated into stable and homogeneous polyurethane structures with the aim of obtaining an improved drug delivery system model. Spectral and thermal analysis was used to investigate the encapsulation process and confirmed the presence of albendazole inside the nanoparticles. The in vitro anticancer properties of albendazole encapsulated in polyurethane structures versus the un-encapsulated compound were tested on two breast cancer cell lines, MCF-7 and MDA-MB-231, in terms of cellular viability and apoptosis induction. The study showed that the encapsulation process enhanced the antitumor activity of albendazole on the MCF-7 and MDA-MB-23 breast cancer lines. The cytotoxic activity manifested in a concentration-dependent manner and was accompanied by changes in cell morphology and nuclear fragmentation.

关键词： polymer matrix   nanofiller   interactions   adsorption   surface   structure   interfacial adhesion  

摘要： It was shown that the physical and/or chemical interactions of the polymer matrix and the nanofiller surface are determined by two factors: the degree of polymer adsorption by the nanofiller and its surface structure. The introduction of a binding agent enhances these interactions and increases the level of interfacial adhesion. If structural factors and physical and/or chemical interactions are known, it is possible to predict the level of interfacial adhesion.

关键词： Chapatti   Amylose   Baking quality   Physicochemical characteristics   Textural characteristics  

摘要： Considerable endeavours have been made to develop improved wheat varieties. In fact, starch with increased level of amylose or resistant starch is one of the key research areas that benefits human health. In this study eight high amylose wheat mutant lines including their parent and market flours were assessed for chapatti quality characteristics on the basis of physicochemical (DSC, XRD, RVA), textural, and sensory parameters. Amylose content of mutant lines ranged from similar to 51 to 75%. Mutant DSC analysis of starch showed variation with increased gelatinization. RVA, XRD, and mixograph data showed variation in starch pasting, crystallinity, and dough characteristics among mutants and parents. 37 other parameters related to grain, starch, flour, dough and chapatti quality were analysed using principal component analysis, ANOVA, and correlation coefficients. Three principal components (PC1, PC2, and PC3) accounted for 68% of the total variation. Strong correlation was observed between amylose and resistant starch content (r(2) = 0.87). Baking time first side (BTFS) had negative impact on eating quality (EQ) (r(2) = 0.81) and pliability was positively correlated to softness (r(2) = 0.99). Except for mutant 'TAC 75' overall quality scores (49.5-55.5) were as good as or better than parent variety, 'C 306' (49.62).

关键词： Physicochemical properties  

摘要： This study aimed to examine the effect of inclusion salmon oil (SO), cod oil (CO), coconut oil (CONT) to wheat starch (WS) on pasting, textural, and in vitro starch digestibility properties. The binary component blend (BCBs) sample showed better complex index (CI) as compared to WS and WS-WG (wheat gluten) and decreased with increasing carbon chain length. The inclusion of lipids to WS significantly reduced pasting and textural characteristics than that of WS alone. In BCBs samples V type amylose-lipid complexes peak at 20 degrees 2 theta and greater short-range molecular order were formed with fatty acids producing more crystalline structure. A similar observation was noted by FTIR, Raman, and NMR spectroscopy. Differential scanning calorimetry (DSC) results suggested that decreased in the gelatinization temperature and enthalpy after addition of different oil sources to WS. The amount of reducing sugar released during starch digestion appears to be dependent on starch hydrolysis. In this study, due to amylose-lipid complex formation, in vitro glycemic response decreased in BCBs samples followed by WS-WG with the ability to act as a barrier to suppress the activity of digestive enzymes to hydrolyze the starch molecules. This altered characteristics of WS might help to formulate the foods to overcome the digestibility concern in humans. Practical applications The results from the present study suggested that comprehending the effect of different lipid sources blend with wheat starch on complex formation, in vitro digestion, structural, and physicochemical properties can provide a guideline regarding alteration of physicochemical and digestibility characteristics of wheat starch which inhibit the accessibility of digestive enzymes to hydrolyze the starch molecules due to amylose-lipid complex formation.