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Reverse wormlike micelles are a potential template for chemical reactions in confined environments. Here, we use time-domain NMR to demonstrate the solvent effect on the mobility of water molecules. The higher the cohesive energy of alkanes, the lower the water mobility, and the less viscous the solution. [ABSTRACT FROM AUTHOR]

Doxycycline (DX) is a well-established and broad-spectrum antimicrobial drug. However, DX has drawbacks, such as physicochemical instability in aqueous media and bacterial resistance. The inclusion of drugs in cyclodextrin complexes and their loading into nanocarriers can overcome these limitations. Thus, we studied the DX/sulfobutylether-β-CD (SBE-β-CD) inclusion complex for the first time and used it to reticulate chitosan. The resulting particles were evaluated by their physicochemical characteristics and antibacterial activity. DX/SBE-β-CD complexes were characterized by nuclear magnetic resonance, infrared spectroscopy, thermal analysis, X-ray diffraction, and scanning electron microscopy (SEM), whereas DX-loaded nanoparticles were characterized by dynamic light scattering, SEM, and drug content. The partial inclusion of the DX molecule in CD happened in a 1:1 proportion and brought increased stability to solid DX upon thermal degradation. Chitosan-complex nanoparticles measured approximately 200 nm, with a narrow polydispersity and particles with sufficient drug encapsulation for microbiological studies. Both formulations preserved the antimicrobial activity of DX against Staphylococcus aureus, whereas DX/SBE-β-CD inclusion complexes were also active against Klebsiella pneumoniae, indicating the potential use of these formulations as drug delivery systems to treat local infections. [ABSTRACT FROM AUTHOR]

Objective: Ova and parasite (O&P) examination is recommended for the laboratory diagnosis of agents causing parasitic infections; however, this exam requires scientific and technological improvements to enhance its diagnostic validity. Dissolved air flotation (DAF) is an efficient technical principle separating suspended solids in a liquid medium. We aimed to develop and validate a new procedure for intestinal parasite detection with DAF. Methods: In this study, we collected samples from 500 volunteers, screened them by direct examination, and transferred the material to tubes using the Three Faecal Test (TF‐Test) for triplicate DAF tests. We evaluated physical–chemical parameters and DAF prototype components through quantifying parasites recovered from floated and non‐floated regions of the flotation column. The DAF operation protocol was validated with the gold standard results. Results: The 10% saturated volume proportion and cationic surfactant showed regularity and high parasite recovery (80%). Modifications of the needle device did not influence parasite recovery (p > 0.05). Sensitivity, specificity, accuracy and kappa agreement obtained with the DAF protocol were 91%, 100%, 93% and substantial (k = 0.64), respectively. Conclusion: The DAF principle could be used to process faecal samples in routine laboratory exams, enabling intestinal parasite detection. [ABSTRACT FROM AUTHOR]

Hybrid meat products are an excellent strategy to incorporate plant proteins into traditional meat formulations considering recent market trends focusing on the partial reduction in red meat content. In this work, we evaluated the effects of different concentrated plant proteins (soy, pea, fava bean, rice, and sunflower) in partially replacing meat in meat emulsion model systems. Soy, pea, and sunflower proteins showed great compatibility with the meat matrix, giving excellent emulsion stability and a cohesive protein network with good fat distribution. Otherwise, adding rice and fava bean proteins resulted in poor emulsion stability. Color parameters were affected by the intrinsic color of plant proteins and due to the reduction in myoglobin content. Both viscoelastic moduli, G′ and G″ decreased with the incorporation of plant proteins, especially for rice and fava bean. The temperature sweep showed that myosin denaturation was the dominant effect on the G′ increase. The water mobility was affected by plant proteins and the proportion between immobilized and intermyofibrillar water was quite different among treatments, especially those with fava bean and rice proteins. In vitro protein digestibility was lower for hybrid meat emulsion elaborated with rice protein. It is concluded that soy, pea, and mainly sunflower proteins have suitable compatibility with the meat matrix in emulsified products. [ABSTRACT FROM AUTHOR]

The structural characteristics of foams are responsible for a broad range of applications of this system. Foams produced by aqueous solutions of surfactant concentrates are used in fire-fighting due to their special properties as extinguishing agents. In the present paper we discuss the main aspects involved in fire-fighting, based on some properties of foams. Thermal and chemical stability, good wetting of surfaces, cooling effect by water drained from the bubbles, isolation of the air from the burning surface and suppression of flammable vapors are some of the factors involved in the extinguishment of fire by foams.

The mechanism of the thermospray formed at low flow rates using a peristaltic pump in thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) is described here for the first time. The study was based on magnified images of the thermospray formed inside the hot tube furnace by using a high-speed CMOS camera. For this purpose different image acquisition speeds were used (from 1000 to 18000 frames/s), revealing that the thermospray obtained under such conditions is quite different from those already reported. The frames of the thermospray evolution indicate that the Leindenfrost effect plays an important role and allow us to propose a mechanism for its formation. The analysis of the images contributed to calculation of parameters related to thermospray formation, such as pulse incidence average (110 [+ or -] 10, 320 [+ or -] 50, and 1200 [+ or -] 150 pulses per second) and pulse speed (6 [+ or -] 1, 10 [+ or -] 1, and 14 [+ or -] 2 m [s.sup.-1]) for 0.1, 0.4, and 1.0 mL [min.sup.-1] flow rate, respectively, for both parameters. Additionally, the evaporation constant ([lambda]) of [10.sup.-4] [m.sup.2] [s.sup.-1] was estimated, and the present thermospray was correlated to the conventional sprays using the Santer mean diameter (SMD) parameter, which ranged from ca. 2 to 44 [micro]m. In order to correlate the information obtained through images with analytical parameters employing the thermospray, the sensitivities for cadmium determination at each condition (0.12, 0.11, and 0.069 s L [micro][g.sup.-1] for 0.1, 0.4, and 1.0 mL[min.sup.-1] flow rate, respectively) were taken into account.

PEO partitioning from water to CH2Cl2 and CHCl3 increases with its molar mass, leveling off at ca. 3 000 g mol-1. Such a behaviour is related to PEO end-group contributions, suggesting a polyglycol to polyether transition at ca. 3 000 g mol-1.

The effects of gelled emulsions (GE) used as animal fat replacers in terms of the nutritional, technological, and sensory properties of Bologna sausages during 60 days of chilled storage have been studied. Samples with GE added exhibited a fat reduction of 31%. Sausages with GE had higher values of L* and lower values of a* compared to the control. Harder sausages were obtained by the addition of GE. Higher lipid oxidation rates were found with increasing amounts of GE in the reformulated products. In addition, the relaxation time was not affected by the reformulation. All samples were deemed acceptable by consumer tests. However, CATA (Check-all-that-apply) tests showed that Bolognas formulated with partial or total pork fat replaced with GE were described as rubbery, not very spicy and firm, appeared to be dry and opaque, and had an aftertaste. Chilled storage significantly affected the Thiobarbituric Acid Reactive Substances (TBARS) values and slightly affected the pH values, texture, color, and NMR data. An important result is that the panelists did not detect the oxidation results in relation to the TBARS values, and the addition of a GE with inulin as dietary fiber may be a good strategy to make Bologna sausage healthier. [ABSTRACT FROM AUTHOR]

BACKGROUND: A high‐fiber emulsion gel (EG) containing inulin, soy protein isolate, and soybean oil was applied as animal fat replacer in reduced salt and fat Bologna sausage containing mechanically deboned chicken meat, pork meat, and pork back fat. Technological and microbiological properties were evaluated for 60 days at 4 °C. RESULTS: A reduction of 11 to 34% and 35 to 45% of fat and sodium were obtained in reformulated products, respectively. An increase in fiber content and polyunsaturated fatty acid was noticed in the formulations with EG. The addition of EG in Bologna increased L* (lightness) values and reduced a* (redness/greenness) values comparing to control treatment. Microstructural properties of sausages exhibited a denser network with the presence of EG. Softer, more elastic, cohesive and resilient samples with a higher intensity of lipid oxidation (P < 0.05) were observed in EG added sausages. The nuclear magnetic resonance (NMR) data shows that the presence of EG recovers the matrix that has been weakened due to reduction of fat and salt. Sensory evaluation showed that the incorporation of the EGs resulted in acceptable scores. CONCLUSION: These results suggest that inulin‐based EG is a potential fat substitute for developing healthier meat products, with better fatty acids composition and stable to chilled storage. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The studies of the spin-spin water relaxations in dilute aqueous solutions of [alpha], [beta], and [gamma]-cyclodextrins (CD), chemically modified [beta]-CD, and other carbohydrates are reported. The lower relaxation rate of water in CD solution is attributed to the intramolecular hydrogen bonding formed between the secondary hydroxyl groups that line the rim of the CDs.

Describes the effects of poly(ethylene oxide) MW, concentration , and chain compaction on the impact structures produced during collision between a droplet against a shallow liquid surface (splash), both liquids containing the polymer. It was observed that the height of the Rayleigh jet, a liquid column produced from the collapse of the crown and the cavity, is highly sensitive to the elongational viscosity of the solution.

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Calorimetric determination of the enthalpies of transfer for partitioning of ethylene oxide oligomers and polymers (PEO) from aqueous to organic phases reveals an endothermic process for all of the systems investigated. Results indicated that spontaneous PEO transfer from water to an organic phase is driven by an entropy increase.