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关键词： QMRA   Enteric viruses   Rainwater harvesting   Potable water   Quality of water  

摘要： The quality of the water consumed by a given community is related to its quality of life. In this sense, this study aimed to evaluate, from the perspective of health risk, the physical, chemical, and microbiological quality of drinking water, in a quilombola community, and the qualitative aspects intrinsic to its use and storage. For this, water samples, collected at the exits of the collective water supply system and from eight cisterns that store rainwater, used for human consumption, were analyzed. The samples were subjected to physical, chemical, and microbiological analysis, including adenovirus (HAdV) and enterovirus (EV). The probability of an individual acquiring infection through water consumption was determined by quantitative microbiological risk analysis using HAdV and Escherichia coli (EC) as reference pathogens. The results showed that the water in the deep tubular well had 270.8 mg/L of total hardness, leading to the rejection of its consumption by ingestion. Alternativity, the people in the community consume rainwater stored in cisterns. For this type of water, the presence of heterotrophic bacteria was found in 75%, total coliform was present in 100%, and Enterococci were detected in 25%. Furthermore, EC was present in 25%, EV in 50%, and HAdV in 100% of the samples. The probability of annual infection with HAdV and EC was, in the worst situation, 100% and 1.3%, respectively. Regarding the qualitative and quantitative aspects, there was a significant positive correlation between the absence of EC and the withdrawal of water from the cistern using a pump and the opposite when the withdrawal was carried out using a bucket or hose. Based on the results found, it is important to carry out actions aimed at improving water quality and, consequently, the quality of life of people living in the study community.

关键词： Meat products   Salt reduction   Micronized salt   EPA   DHA   Microencapsulation   Complex coacervation  

摘要： This study aimed to determine the effect of NaCl reduction and addition of long-chain polyunsaturated fatty acids (PUFA) on the quality traits of burgers. Fish oil was either directly incorporated or added as encapsulated by freeze-dried microparticles (complex coacervates) composed of soy protein isolate and inulin. Despite the differences in some parameters associated with NaCl reduction (e.g., instrumental hardness), the quality of the burgers was mainly affected by the microparticles. Thus, a decrease in pH and increase in hardness and chewiness were observed, and a higher exposure of fish oil to oxidation was observed thus increasing volatile oxidation compounds and negatively impacting on the sensory profile and overall liking of the burgers. However, the encapsulation of the fish oil helped to retain EPA and DHA after cooking. The results of the NaCl-reduced burger with unencapsulated fish oil suggest the possibility of incorporating PUFAs, but only containing EPA after cooking.

关键词： Corn starch   Degradation   Electron beam   Irradiation   Plasma   Apparent viscosity  

摘要： The paper deals with the investigation of the effects of corona electrical discharge (CED) treatment in conjunction with electron beam irradiation (EBI) on starch physicochemical properties. Acidity, paste clarity, gel consistency, apparent and intrinsic viscosities of corn starch subjected to the combined treatments were investigated and compared to the corresponding single treatment. The findings showed that the combined treatments based on CED and EBI, respectively, are able to modify the technological properties of starch, depending on the application sequence of CED, as a consequence of the degradation phenomenon. The degradation rate constant proved clearly that the combined CED/EBI treatment had the greatest efficiency in the changing of starch properties among all studied treatments. Also, this study revealed that the use of CED as a pre-treatment to EBI of starch can reduce the minimum irradiation dose required for certain industrial application by influencing more the sensitivity of starch to radiation.

关键词： Solubility   Dentin permeability   Titanium tetrafluoride   Adhesives   Particle size  

摘要： Titanium tetrafluoride (TiF4) in an aqueous solution can decrease dentin permeability, but some effects of its incorporation into adhesive systems are not yet known. Therefore, the aim of this study was to characterize the physicochemical, water sorption (WS) and solubility (SL) properties of two adhesive systems (Clearfil SE Bond/C and Scotchbond Universal/S) incorporated with 0.0% (T0), 2.5% (T2) and 4.0% (T4) titanium tetrafluoride (TiF4), and determine dentin permeability (L) after application of these adhesive systems both immediately afterwards (baseline) and after 6 months of storage. The physicochemical analyses of the incorporated solutions were performed based on evaluating particle size (PS), polydispersity index (PDI) by dynamic light scattering, and zeta potential (ZP) by electrophoresis. WS and SL tests followed ISO 4049 standards, and used a 7-day water storage period. The L test was performed by analyzing human dentin discs before and after adhesive system application, and after storage. PS and PDI were higher for CT0 and ST4 (p < 0.0001;ANOVA, Tukey). ZP was lower for CT4, ST2 and ST4 (p < 0.0001;ANOVA, Tukey). A 4.0% TiF4 incorporation showed higher WS (p < 0.05;Mann Whitney, Kruskal Wallis, Dunn). Higher SL was observed for CT0 and ST4 (p < 0.05;Mann Whitney, Kruskal Wallis, Dunn). The L value at baseline was lower for ST4, but was not different from the CT4 groups after storage (p < 0.05;Mann Whitney, Kruskal Wallis, Dunn). It can be concluded that TiF4 affected the colloidal stability of Scotchbond, but did not alter the other properties. The 2.5% TiF4 did not affect the PDI, WS or L of the Clearfil, and can be considered an alternative for reducing hybrid layer degradation.

关键词： Ecotoxicology   Biotest   Hazard   Wastewater treatment plants   Pilica River catchment   Ecohydrology  

摘要： While legal regulations require treated wastewater to be tested based only on its physicochemical parameters, surface water assessment also has to include biological indicators. However, neither approach provides a complete picture of water quality due to lack of ecotoxicological information. Therefore, the aim of the study was to perform an ecotoxicological evaluation of treated wastewater and river water in the catchment scale using a battery of biotests. In the period between June 2017 and July 2018, six sets of treated wastewater samples were taken from 17 municipal wastewater treatment plants (WWTPs) of different sizes (small: < 2,000 people equivalent - p.e.;medium size: 2,000?9,999 p.e.;large: 15,000?99,999 p.e.), as well as river water samples from seven sites along the 342 km Pilica River in central Poland. Physical and chemical analysis were performed of total nitrogen (TN), total phosphorus (TP), biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS), as well as organic suspended matter (OSM), ion content (fluorides, nitrates, ammonium, potassium and sulphate), and pH, conductivity and redox potential (RP). Ecotoxicity assessment was performed using a battery of biotests comprising the producer Pseudokirchneriella subcapitata (chronic toxicity biotest), consumer Thamnocephalus platyurus (acute toxicity biotest) and decomposer Tetrahymena thermophila (chronic toxicity biotest). It was found that in small WWTPs, the recommended levels of TN, TP, BOD, COD and TSS were often exceeded. Also, the highest mean toxicity hazard in the ecotoxicological biotests was observed for samples from small WWTPs. No clear dependence was found between any of the studied physicochemical parameters of the water and the ecotoxicity of samples: however, a correlation was observed between growth inhibition of P. subcapitata and TN and NH4+ concentration (r = 0.43 and r = 0.48, respectively). Also, the mortality of T. platyurus was correlated

关键词： bio‐   template kapok   electrophoretic deposition   magnetic zinc ferrite   photoelectrochemical  

摘要： Surface-modified zinc ferrite nanocomposites were successfully prepared thru ultrasonic impregnation technique by taking kapok fiber as a bio-template. This work demonstrates a fast preparation method to produce the bio-templated ZnFe2O4 composite photocatalyst. The templating method for photocatalyst is favorable due to the benefit of a large surface area for solar harvesting activities in the photoelectrochemical (PEC) system. Comprehensive physicochemical analyses have successfully determined the unique properties of the prepared catalysts. The pure mimetic fibrous catalysts were successfully fabricated as photoelectrodes on the fluorine tin oxide substrate using electrophoretic deposition technique for PEC measurement. The ranging ratio of precursors used to prepare bio-templated zinc ferrite catalysts shows an effect on their surface structure then influences the photocurrent density performance of PEC analysis. The ZF1 photoanode at 1:1 Zn/Fe ratio has generated the highest photocurrent density of 58 mu A cm(-2) at 0.7 V vs. Ag/AgCl compare to other samples in 0.5 M Na2SO4 electrolyte solution under 100 mW cm(-2) light irradiation. The high photocurrent density was attributed to the enhancement in light-harvesting properties, fine surface structure, and high charge transfer properties that correlate with the composite ratio's alteration. The bio-templated zinc ferrite photocatalysts are a promising photoanode in PEC activities.

关键词： Rice flour   Chlorogenic acid   Extrusion   Physicochemical property digestibility  

摘要： To investigate how chlorogenic acid (CHA) affects the physicochemical properties and hydrolysis of rice flour during extrusion. CHA was extruded with rice flour through a twin-screw extruder at different concentrations (0 +/- 2.0%), and the physicochemical properties of the extrudates, including crystallinity, pasting properties and CHA binding, were characterized through X-ray diffraction, Fourier-transform infrared spectroscopy, Rapid Visco Analyzer and ultraviolet spectrophotometer. Particularly, starch hydrolysis and the release of CHA were also evaluated through enzymatic hydrolysis and high-performance liquid chromatography. Results indicated that the addition of CHA promoted the formation of V-type crystals and increased the orderliness of the complexes. The maximum binding amount of CHA in extrudates was 10.98 mg/g without any isomerization or degradation. Additionally, the rapidly digestive starch (RDS) decreased markedly (down to 41.28 +/- 2.66%), and there was a pronounced increase in resistant starch (RS), which varied from 10.28 +/- 2.62 to 31.16 +/- 0.50% in different extrudates. Our results indicated that CHA yielded a negative effect on starch hydrolysis and might provide basic guidance for the application of CHA to healthy starchy food processing in the future.

关键词： Moisture  

摘要： The present research was undertaken to optimize process conditions for development of water chestnut incorporated corn-based extrudates. The independent extrusion variables-feed composition, feed moisture, screw speed and barrel temperature were studied to determine their influence on dependent variables-specific mechanical energy, expansion index, bulk density, water solubility index, water absorption index, hardness, and color. All system and product responses were significantly (p < .05) influenced by independent variables. The regression models fitted to experimental design showed high coefficient of determination (R-2 >= 0.99). The optimum conditions for development of extrudates obtained by numerical optimization were corn flour : water chestnut flour (60:40), feed moisture (14%), barrel temperature (170 degrees C), and screw speed (300 rpm). Moisture, protein, and fat contents of extrudates developed using optimum conditions were significantly (p < .05) lower than corn and water chestnut. Storage studies revealed safe storage of extrudates packed in aluminum laminates up to 120 days under ambient conditions without compromising much of its qualities. Practical applications Water chestnut possesses excellent therapeutic potential owing to the presence of bioactive compounds including glycosides, phytosterols, flavonoids, and tannins, which may help in alleviating various diseases. Besides, water chestnut has low glycemic index;thus, the developed products prepared from it may be suitable for diabetics. Extruded products have better consumer acceptability in terms of shelf life and organoleptic characteristics. Therefore, the extruded products developed from nutritionally rich water chestnut would be a better alternative to already available extruded snacks in food industry. It can open up a new horizon in the field of extrusion products.

关键词： Al2O3-ZrO2 (Y2O3   CeO2) system   ZTA composites   hydrothermal synthesis in alkaline environment   nanocrystalline powder   shape factor   ZrO2 solid solution  

摘要： Alumina-based nanocrystalline powders with different ZrO2 amounts were produced for the first time by hydrothermal synthesis in an alkaline environment for designing zirconia toughened alumina (ZTA) composites. In ZTA composites, ZrO2 solid solution particles codoped with ceria and yttria are distributed in a rigid Al2O3 matrix. To examine the physicochemical properties, 90 wt.% Al2O3-10 wt.% ZrO2 (Y2O3, CeO2) and 58.5 wt.% Al2O3-42.5 wt.% ZrO2 (Y2O3, CeO2) powders were used. The ZrO2 solid solution had composition 90 mol.% ZrO2-2 mol.% Y2O3-8 mol.% CeO2. The hydrothermal powders were heat treated in the temperature range 400-1450 degrees C and examined by X-ray diffraction, differential thermal analysis, and electron microscopy. The powder specific surface area was determined by the BET method. The sizes of primary particles were determined with the Scherrer equation. The AMIC software (Automatic Microstructure Analyzer) was employed to process the morphology analysis results. The phase transformations and active sintering of the ZTA powders determined the dependences showing the sizes of primary particles and the specific surface area of the powders versus the heat treatment temperature. With higher ZrO2 content, temperature of the F-ZrO2 -> T-ZrO2 phase transformation decreased, the likelihood of M-ZrO2 to emerge increased, and the sequence of Al2O3 phase transformations changed after the boehmite had decomposed. The variation in the morphology and specific surface area of the powders in the heat treatment process indicated that their sintering activity increased. The dependence of the shape factor characterizing the nanocrystalline 90AZG and 58.5AZG powders on the heat treatment temperature was studied. The starting nanosized 90AZG and 58.5AZG powders had a similar distribution of agglomerates according to the shape factor. Round agglomerates and multifaceted regular agglomerates were predominant. The way in which the shape factor of the agglomerates varied with

摘要： Proteolytic instability is a critical limitation for peptide-based products. Although significant efforts are devoted to stabilize sequences against proteases/peptidases in plasma/serum, such approaches tend to be rather empirical, unspecific, time-consuming, and frequently not cost-effective. A more rational and potentially rewarding alternative is to identify the chemical grounds of susceptibility to enzymatic degradation of peptides so that proteolytic resistance can be tuned by manipulation of key chemical properties. In this regard, we conducted a meta-analysis of literature published over the last decade reporting experimental data on the lifetimes of peptides exposed to proteolytic conditions. Our initial database contained 579 entries and was curated with regard to amino acid sequence, chemical modification, terminal half-life (t(1/2)) or other stability readouts, type of stability assay, and biological application of the study. Although the majority of entries in the database corresponded to (slightly or substantially) modified peptides, we chose to focus on unmodified ones, as we aimed to decipher intrinsic characteristics of peptide proteolytic susceptibility. Specifically, we developed a multivariable regression model to unravel those peptide properties with most impact on proteolytic stability and thus potential t(1/2) predicting ability. Model validation was done by two different approaches. First, a library of peptides spanning a large interval of properties that modulate stability was synthesized and their t(1/2) in human serum were experimentally determined. Second, the t(1/2) of 21 selected peptides approved for clinical use or in clinical trials were recorded and matched with the model-estimated values. With both approaches, good correlation between experimental and predicted t(1/2) data was observed.