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Proper interpretation of analytical ultracentrifugation (AUC) data for purified proteins requires ancillary information and calculations to account for factors such as buoyancy, buffer viscosity, hydration, and temperature. The utility program SEDNTERP has been widely used by the AUC community for this purpose since its introduction in the mid-1990s. Recent extensions to this program (1) allow it to incorporate data from diffusion as well as AUC experiments; and (2) allow it to calculate the refractive index of buffer solutions (based on the solute composition of the buffer), as well as the specific refractive increment ( dn/dc ) of proteins based on their composition. These two extensions should be quite useful to the light scattering community as well as helpful for AUC users. The latest version also adds new terms to the partial specific volume calculations which should improve the accuracy, particularly for smaller proteins and peptides, and can calculate the viscosity of buffers containing heavy isotopes of water. It also uses newer, more accurate equations for the density of water and for the hydrodynamic properties of rods and disks. This article will summarize and review all the equations used in the current program version and the scientific background behind them. It will tabulate the values used to calculate the partial specific volume and dn/dc , as well as the polynomial coefficients used in calculating the buffer density and viscosity (most of which have not been previously published), as well as the new ones used in calculating the buffer refractive index.

This study aimed to perform a systematic review on gluten-free bread formulations using specific volumes as a quality indicator. In this systematic review, we identified 259 studies that met inclusion criteria. From these studies, 43 met the requirements of having gluten-free bread with a specific volume greater than or equal to 3.5 cm3/g. Other parameters such as the texture profile, color (crumb and crust), and sensory analysis examined in these studies were presented. The formulations that best compensated the lack of the gluten-network were based on the combination of rice flour, rice flour with low amylose content, maize flour, rice starch, corn starch, potato starch, starch with proteins and added with transglutaminase (TGase), and hydrocolloids like hydroxypropylmethylcellulose (HPMC). Of the 43 studies, three did not present risk of bias, and the only parameter evaluated in common in the studies was the specific volume. However, it is necessary to jointly analyze other parameters that contribute to the quality, such as texture profile, external and internal characteristics, acceptability, and useful life of the bread, especially since it is a product obtained through raw materials and unconventional ingredients.

We analyze high-resolution (1 km) simulations of the western Pacific, Gulf of Mexico, and Arabian Sea to understand submesoscale eddy dynamics. A mask based on the Okubo–Weiss parameter isolates small-scale eddies, and we further classify those with | ζ / f | ≥ 1 as being submesoscale eddies. Cyclonic submesoscale eddies exhibit a vertical depth structure in which temperature anomalies from the large-scale background are negative. Peak density anomalies associated with cyclonic submesoscale eddies are found at a depth approximately twice the mixed layer depth (MLD). Within anticyclonic submesoscale eddies, temperature anomalies are positive and have peak density anomalies at the MLD. The depth–depth covariance structure for the cyclonic and anticyclonic submesoscale eddies have maxima over a shallow region near the surface and weak off diagonal elements. The observed vertical structure suggests that submesoscale eddies have a shallower depth profile and smaller vertical correlation scales when compared to the mesoscale phenomenon. We test a two-dimensional submesoscale eddy dynamical balance. Compared to a geostrophic dynamical balance using only pressure gradient and Coriolis force, including velocity tendency and advection produces lower errors by about 20%. In regions with strong tides and associated internal waves (western Pacific and Arabian Sea), using the mixed layer integrated small-scale steric height within the dynamical equations produces the lowest magnitude errors. In areas with weak tides (Gulf of Mexico), using small-scale sea surface height (SSH) produces the lowest magnitude errors. Recovering a submesoscale eddy with the correct magnitude and rotation requires integration of small-scale specific volume anomalies well below the mixed layer.

The influence of the content of fibrous basalt on the temperature dependence of the specific volume of composites based on thermoplastic elastomer was investigated. A mechanical mixture of polypropylene with 30 wt % butadiene-styrene copolymer was used as a thermoplastic elastomer. To improve the technological compatibility of the mixed components of the mixture, a compatibilizer was used, which was modified with 1.5 wt % maleic anhydride content. The content of fibrous basalt in the composition of the thermoplastic elastomer varied within the range of 5.0–20 wt %. It was shown that for composites with 5.0–15 wt % fibrous basalt content, the first-order phase transition occurs at a temperature of 159°C. For a sample with 20 wt % fibrous basalt content, the value of this indicator increases to 168°C. Based on the data of dilatometric curves constructed in the temperature range of 20–210°C, a decrease in the specific volume or an increase in the density of composites with an increase in the content of fibrous basalt was recorded. Only at 20 wt % filler content did the specific volume increase in this temperature range. By extrapolating the dilatometric curves to the region of absolute zero (–273°C) for composites with different fiber filler contents, the “occupied” specific volume was found. This made it possible to construct a dependence of the “free” specific volume on temperature. At the temperature of the first-order phase transition, i.e. from a viscous-flowing to a solid state, the mechanism and kinetic regularities of crystallization were studied in Kolmogorov–Avrami coordinates under the condition of continuous formation of nucleation centers. It was established that in filled thermoplastic elastomers the isothermal crystallization process proceeds according to the linear (rod-like) type of growth of crystalline formations.

Apparent molar volumes (ϕV) of glycine/l-alanine in water and in aqueous citric acid (CA) solutions of varying concentrations, i.e. (0.05, 0.10, 0.20, 0.30, 0.40 and 0.50) mol·kg−1 were determined from density measurements at temperatures T = (288.15, 298.15, 308.15, 310.15 and 318.15) K and at atmospheric pressure. Limiting partial molar volumes (ϕVo) and their corresponding partial molar volumes of transfer (ΔtrϕV) have been calculated from the ϕV data. The negative ΔtrϕV values obtained for glycine/l-alanine from water to aqueous CA solutions indicate the dominance of hydrophilic–hydrophobic/hydrophobic–hydrophilic and hydrophobic–hydrophobic interactions over ion/hydrophilic–dipolar interactions. Further, pair and triplet interaction coefficients, i.e. (VAB)and(VABB) along with hydration number (nH) have also been calculated. The effect of temperature on the volumetric properties of glycine/l-alanine in water and in aqueous CA solutions has been determined from the limiting partial molar expansibilities (∂ϕVo/∂T)p and their second-order derivative (∂2ϕVo/∂T2)P . The apparent specific volumes (νϕ) for glycine and l-alanine tend to approach sweet taste behavior both in the presence of water and in aqueous CA solutions. The νϕ values for glycine/l-alanine increase with increase in concentration of CA at all temperatures studied. This reveals that CA helps in enhancing the sweet taste behavior of glycine/l-alanine which also supports the dominance of hydrophobic–hydrophobic interactions.

In numerical simulation of injection molding, the specific volume is important for the cavity pressure prediction, which governs the part properties, such as shrinkage and warpage. The specific volume is often considered as a function of pressure and temperature only. This neglects its cooling rate dependence. The related degradation of the cavity pressure prediction usually remains unknown. In this work, the cooling rate effect is modeled and the discrepancy is quantified for amorphous polystyrene. A rate equation is used to model the specific volume relaxation within the scope of three-dimensional computational fluid dynamics. The model incorporates the mold compliance to allow a comparison to the experimental results. The cavity pressure evolution and the final residual stresses are calculated for both the modeled and the neglected cooling rate effects. This provides argumentation for either neglecting or modeling the phenomenon.

Many varieties of soft wheat in China cannot fully satisfy the requirements of making high-quality cakes due to their undesirable protein properties, which leads to shortages of high-quality soft wheat flour. Therefore, a modification of soft wheat protein is essential for improving the quality of soft wheat and thus improving cake quality. In order to modify the protein properties of soft wheat used for cake production, superheated steam (SS) was used to treat soft wheat grains at 165 °C and 190 °C for 1, 2, 3, 4, and 5 min, respectively, followed by the milling of wheat grains to obtain refined wheat flour. The properties of proteins and cakes were analyzed using refined wheat flour as materials. First, changes in the structures of wheat proteins were analyzed by determining the solubility, molecular weight distribution and secondary structure of proteins in wheat flour. Secondly, changes in the functional properties of proteins were analyzed by determining the foaming properties and emulsifying properties of proteins in wheat flour. Finally, the specific volume and texture of cakes with wheat flour milled from SS-treated wheat were analyzed. At the initial stage of SS treatment, some of the gliadin and glutenin aggregated, and the gluten macro-polymer (GMP) contents increased. This allowed a more stable gluten network to form during dough kneading, leading to an improvement in dough elasticity. In addition, a short time period (1–3 min) of SS treatment improved the emulsifying properties and foaming ability of wheat protein, which helped to improve the specific volume and texture of cakes. Increasing the SS temperature from 165 °C to 190 °C reduced the optimal treatment time needed to improve cake quality from 3 min to 1 min. SS treatment for longer time (>3 min) periods led to severe protein aggregation and a decrease in the foaming ability and emulsifying properties of protein, which led to a deterioration in the cake quality. Thus, SS treatment at 165 °C for 1–3 min and 190 °C for 1 min could be a suitable method of improving the physicochemical properties of soft wheat used to make cakes with high specific volumes and good texture.

The article presents the results of studies of the influence of aluminum hydroxide concentration on the regularities of changes in the crystallization process of composite materials based on a polypropylene random copolymer / processing aid / aluminum hydroxide (PP-R/ LIBAID T-2 /Al(OH)3). In this study, LIBAID T-2 was used as a physical coupling agent to improve the compatibility between polypropylene random copolymer and aluminum hydroxide. The amounts of aluminum hydroxide varied within the range of 1-50 wt%. The crystallization process of composites was studied by the stepwise dilatometric method under a load of 5.3 kg on the IIRT-1 device, converted into a dilatometer. The following parameters have been determined, such as specific volume, density, occupied and free specific volume, temperature of first-order phase transition and isothermal crystallization, and glass transition temperature. The glass transition temperature of the studied polymer composites increased with an increase in the content of aluminum hydroxide in the polymer matrix. The crystallization temperature for all studied samples was 120 °C. With an increase in the amount of aluminum hydroxide, a decrease in the specific volume value and, accordingly, an increase in density were observed. Based on the Kolmogorov-Avrami equation, the kinetic regularities of isothermal crystallization of the studied composites were studied and the mechanism of formation of crystalline structures depending on the content of the introduced filler in the composition of the polypropylene random copolymer was described.

This study  was investigates the effect of adding different concentrations (1, 2, 3, 4, 5, 6, 7, 8) % of mallow (Malva  neglecta L.) leaves powder (MLP) to wheat bread mix on nutritional and qualitative properties of the obtained bread. Results of the chemical composition based by dry matter, moisture, ash, protein, fat, and carbohydrates for wheat flour and mallow leaves powder were 87.4, 12.6, 0.65, 10.5, 1.25, 75% and 96.2, 3.8, 7.90, 12.70, 1.60, 74.20 %, respectively. The study included nine treatments (T1, T2, T3, T4, T5, T6, T7, T8, T9 ), where T1 was the control treatment. During the fermentation period, dough  mass was  increased to its maximum value, T1 recorded the lowest height. The addition of (MLP) led to a slight increase in the specific volume of (T2, T3, T4, T5, T6), and this may be due to the increase in the proportion of polysaccharides in the mallow plant, while the specific volume began to decrease significantly in treatments (T7, T8, T9). Each of (T7, T8, and T9) showed significant differences as compared with the control treatment (T1) for the characteristics of color of crust, symmetry of form, evenness of bake, grain, color, texture of crumb,  aroma, and taste. There were no significant differences between (T2, T3, T4, T5, T6) compared with T1. The results indicate that the consumer accepted T2, T3, T4, and T5 treatments as well as T1. GC analysis showed the presence of phenolic compounds in mallow leaves powder, such as phenol, 2-chlorophenol, 2-methyl phenol, 4-methyl phenol, 2-nitrophenol, 2,4-dimethylphenol, benzoic acid, 2, 4- Dinitrophenol (0.150, 0.036, 0.03, 0.127, 1.360, 0.042, 0.002, 5.552 mg\\100g) respectively.

Several studies have indicated that forest characteristics can be accurately predicted using airborne laser scanner (ALS) data, but there are very few studies in which species-specific forest characteristics have been estimated. This article compares two approaches for determining species-specific volumes at plot level by combining ALS data with aerial photographs. The first approach consists of two stages: (1) prediction of total volume using ALS data, and (2) assignment of this total volume to tree species by fuzzy classification and aerial photographs, in which three fuzzy classification methods were tested. In the second approach, volumes by tree species and the total volume are predicted simultaneously using a nonparametric k-most similar neighbor (k-MSN) method based on both ALS data and aerial photographs in one phase. The test area, located in Finland, consists of 463 sample plots. Species-specific volumes were estimated for pine, spruce, and the deciduous trees as a species group, total volume being the sum of the species-specific volumes. The k-MSN method produced considerably more accurate estimates for the species-specific volumes than any fuzzy classification method, the relative RMSEs for the volumes of pine, spruce, and deciduous trees being 45.50%, 61.98%, and 92.30%, respectively, and that for the total volume 23.86%.