Search Results (830)

This study applies Computational Fluid Dynamics (CFD) and mathematical modeling to examine uterine and umbilical arterial blood flow during pregnancy, providing a more detailed understanding of hemodynamic changes across gestation. Statistical analysis of Doppler ultrasound data from a large cohort of more than 200 pregnant women (in the second and third trimesters) reveals significant increases in the umbilical arterial peak systolic velocity ($PSV$) between the 22nd and 30th weeks, while uterine artery velocities remain relatively stable, suggesting adaptations in vascular resistance during pregnancy. By combining the Navier–Stokes equations with Doppler ultrasound-derived inlet velocity profiles, we quantify several key fluid dynamics parameters, including time-averaged wall shear stress ($TAWSS$), oscillatory shear index ($OSI$), relative residence time ($RRT$), Reynolds number ($Re$), and Dean number ($De$), evaluating laminar flow stability in the uterine artery and secondary flow patterns in the umbilical artery. Since blood exhibits shear-dependent viscosity and complex rheological behavior, modeling it as a non-Newtonian fluid is essential to accurately capture pulsatile flow dynamics and wall shear stresses in these vessels. Unlike conventional imaging techniques, CFD offers enhanced visualization of blood flow characteristics such as streamlines, velocity distributions, and instantaneous particle motion, providing insights that are not easily captured by Doppler ultrasound alone. Specifically, CFD reveals secondary flow patterns in the umbilical artery, which interact with the primary flow, a phenomenon that is challenging to observe with ultrasound. These findings refine existing hemodynamic models, provide population-specific reference values for clinical assessments, and improve our understanding of the relationship between umbilical arterial flow dynamics and fetal growth restriction, with important implications for maternal and fetal health monitoring. Full article

This study aimed to optimize the inoculation dosage and fermentation duration to enhance the protein content and reduce soluble oligosaccharides in soybean meal using Aspergillus oryzae and assessed its performance in dog food extrusion. A 3 × 5 factorial design was used to determine the optimal fermentation conditions. These conditions were applied to ferment soybean meal in bulk for nutritional analysis. Finally, the impact of fermentation on extrusion processing was assessed by formulating and extruding four diets: SBM (30% soybean meal), AMF (30% soybean meal with 1% Amaferm^®—A. oryzae biomass), FSBM (30% fermented soybean meal), and SPI (18% soy protein isolate). Diets were extruded with a single-screw extruder, and physical characteristics of kibbles, particle size distribution, and viscosity of raw mixes were analyzed. The optimal fermentation conditions were 1 × 10⁴ spore/g substrate for 36 h, which increased the crude protein content by 4.63% DM, methionine and cysteine total content by 0.15% DM, and eliminated sucrose, while significantly reducing stachyose, raffinose, and verbascose (95.22, 87.37, and 41.82%, respectively). The extrusion results showed that FSBM had intermediate specific mechanical energy (SME), in-barrel moisture requirements, and sectional expansion index (198.7 kJ/kg, 28.2%, and 1.80, respectively) compared with SBM (83.7 kJ/kg, 34.5%, and 1.30, respectively) and SPI (305.3 kJ/kg, 33.5%, and 2.55, respectively). The FSBM also exhibited intermediate particle size distribution and the least raw mix viscosity. These findings demonstrate that A. oryzae fermentation enhances the nutrient profile of soybean meal while improving extrusion efficiency and kibble quality, supporting its potential use as a sustainable pet food ingredient. Full article

Backgroun/Objectives: Recent pharmaceutical research has increasingly focused on eutectic systems to improve the formulation and delivery of active pharmaceutical ingredients (APIs). This study presents the preparation and characterization of three therapeutic eutectic systems (THEESs) based on ibuprofen and menthol at various molar ratios. Methods: The THEESs were prepared and analyzed by assessing their physicochemical properties and rheological properties were evaluated to determine flow behavior. Cytotoxicity assays were conducted on HaCaT and HepG2 cell lines to assess biocompatibility. Results: All systems formed monophasic, homogeneous, clear and viscous liquids. Key physicochemical properties, including density, refractive index, surface tension, speed of sound and isobaric heat capacity, showed a temperature-dependent, inverse proportional trend. Viscosity followed the Vogel–Fulcher–Tammann equation, and rheological analysis revealed non-Newtonian behavior, which is important for pharmaceutical processing. Notably, cytotoxicity assays revealed that Ibu-M3 and Ibu-M4 showed lower toxicity than pure compounds in HaCaT cells, while Ibu-M5 was more toxic; in HepG2 cells, only Ibu-M3 was less toxic, whereas Ibu-M4 and Ibu-M5 were more cytotoxic than the pure compounds. Conclusions: These findings highlight the potential of ibuprofen–menthol eutectic systems for safer and more effective pharmaceutical formulations. Full article

The intense demand for alternatives to conventional plastics has increasingly motivated the development of biodegradable packaging. However, the ecological impact of these materials when discarded in natural settings has not yet been evaluated. Therefore, this study investigated the effects of films based on chia mucilage in different aquatic environments. The solubilization time varied according to water type, ranging from 40 min in ultrapure, deionized, and distilled water to 230 min in saline water. After solubilization, all water samples exhibited increased turbidity (from 1.04 to 15.73 NTU in deionized water) and apparent color (from 0 to 44 PCU in deionized water) as well as pH variations depending on ionic strength. Deionized water also showed the highest viscosity increase (>350 Pa·s at 1 s⁻¹). UV–Vis spectra revealed a moderate rise in absorbance between 236 and 260 nm, indicating organic compound release. Regarding phytotoxicity, the solubilized films had no toxic effect and promoted a biostimulating effect on root elongation, with Relative Germination Index values exceeding 140% in most samples. These results reinforce the potential of chia-based films for controlled disposal, particularly in low-salinity environments, while highlighting the importance of evaluating post-solubilization interactions with aquatic systems. Full article

This study investigated how microparticle size affects natural convective heat transfer in high-viscosity suspensions. Suspensions were formulated using 0.5% xanthan gum and 3% stearic acid, with particle sizes ranging from 120 to 750 nm. Key thermal properties, including thermal conductivity (0.598–0.679 W/m·K), specific heat, and the volumetric thermal expansion coefficient (0.990–1.000/°C), were measured. Rheological analysis based on the Herschel–Bulkley model revealed that reducing the particle size increased the consistency index from 0.56 to 0.75 Pa·s, while reducing the flow index from 0.63 to 0.50. This indicates enhanced shear-thinning behavior. A Rayleigh–Bénard convection system revealed that suspensions containing smaller particles exhibited higher Rayleigh and Nusselt numbers under large temperature gradients. Nusselt numbers reached values of up to 100 at a temperature difference of 9 °C. Conversely, suspensions containing larger particles exhibited relatively higher Rayleigh and Nusselt numbers under smaller temperature differences. These results demonstrate that optimizing microparticle size can enhance the efficiency of heat transfer in high-viscosity suspensions depending on the applied thermal gradient. This has practical implications for improving heat transfer in food and other viscous systems where convection is limited. Full article

Raicilla is a distinctive Mexican beverage produced in two central regions of Jalisco. This study aimed to analyze the physicochemical parameters of 25 raicilla alcoholic drinks originating from the Coast and Sierra regions. Each of the 25 raicilla brands underwent measurements of pH, conductivity, alcohol content, total solids, viscosity, sound velocity, density, and refractive index. Notably, these measurements are cost-effective and their analysis is straightforward. The results were analyzed using principal component analysis (PCA) and cluster analysis. According to the PCA, two main components were identified, explaining 81.77% of the total variability of the physicochemical measurements of the distinct Coast and Sierra regions. Furthermore, applying Fisher’s LSD to the Sierra raicilla cluster allowed for the identification of variations. Specifically, samples from the Sierra zone groups were identified through cluster analysis, demonstrating similarities in physicochemical parameters; both statistical methods indicated no significant differences in the physicochemical parameters between a more acidic pH, higher conductivity, and greater density than those from the Coast zone. After the analysis was carried out, it was possible to find similarities and differences between the raicilla produced in the two regions, so it is possible to assume that using these results could facilitate the authentication of raicilla. Full article

This study explored the potential of chitosan (CH)/bacterial cellulose (BC) complexes (0.5% w/v) as novel emulsifiers to stabilize oil-in-water (o/w) Pickering emulsions (20% v/v sunflower oil), with a focus on their gel-like behavior. Emulsions were prepared using CH combined with BNC derived via H₂SO₄ (BNC1) or H₂SO₄-HCl (BNC2) hydrolysis. Increasing BNC content improved stability by reducing phase separation and enhancing viscosity, while CH contributed interfacial activity and electrostatic stabilization. CH/BNC1_25:75 emulsions showed the highest stability, maintaining an emulsion stability index (ESI) of up to 100% after 3 days, with minimal change in droplet size (R_h ~8.5–8.8 μm) and a positive ζ-potential (15.1–29.8 mV), as confirmed by dynamic/electrophoretic light scattering. pH adjustment to 4 and 10 had little effect on their ESI, while ionic strength studies showed that 0.1 M NaCl caused only a slight increase in droplet size combined with the highest ζ-potential (−35.2 mV). Higher salt concentrations led to coalescence and disruption of their gel-like structure. Rheological analysis of CH/BNC1_25:75 emulsions revealed shear-thinning behavior and dominant elastic properties (G′ > G″), indicating a soft gel network. Incorporating sunflower-seed protein isolates into CH/BNC1 (25:75) emulsions led to coacervate formation (three-layer system), characterized by a decrease in droplet size and an increase in ζ-potential (up to 32.8 mV) over 7 days. These findings highlight CH/BNC complexes as sustainable stabilizers for food-grade Pickering emulsions, supporting the development of biopolymer-based emulsifiers aligned with bioeconomy principles. Full article

Background/Objectives: Basil essential oil exhibits a wide range of biological activities, including strong antimicrobial and anti-inflammatory effects. Considering the health benefits of basil essential oil (BEO) and the favorable properties of alkyl polyglucoside emulsifiers, novel Montanov™-68-based O/W creams containing BEO were developed and characterized. Additionally, the influence of the emulsifier content on the cream’s properties was evaluated. Methods: The physicochemical properties were evaluated by organoleptic examination, physical stability test, and pH and electrical conductivity measurement. The mechanical properties were investigated by rheological, textural, and consistency analyses. In addition, a sensory evaluation protocol was applied. Results: The cream formulations containing 5% and 7% Montanov™ 68 demonstrated physical stability, with no evidence of phase separation during the observation period or following accelerated aging. The pH values remained within the acceptable range for topical use, and a gradual decrease in electrical conductivity over time was observed. The rheological analyses confirmed the non-Newtonian pseudoplastic behavior with thixotropic flow characteristics. The textural analyses demonstrated that the higher emulsifier content led to increased firmness, consistency, cohesiveness, and index of viscosity. The sensory analysis revealed differences between the alkyl polyglucoside (APG)-based cream formulations only in terms of the elasticity and stickiness. Conclusions: Although the rheological analyses suggested the better spreadability of the formulation with 5% emulsifier, this was not confirmed by the sensory analysis. However, the APG-based formulations performed significantly better than the synthetic surfactant-based formulation in terms of the absorption, stickiness, and greasiness (during and after application). These results are encouraging for the further evaluation of APG-based creams containing basil essential oil for topical application. Full article

This study explored the effects of adding a newly developed type of polydextrose on the appearance, sensory score, and textural parameters of steamed bread and the microstructure of dough, as well as the pasting, thermal, and thermal mechanical properties of high-gluten wheat flours. The results revealed that, compared with a control sample, 3–10% of polydextrose addition significantly increased the hardness, adhesiveness, gumminess, and chewiness of steamed bread, but other textural parameters like springiness, cohesiveness, and resilience remained basically the same. Further, in contrast to the control sample, 3–10% polydextrose addition significantly reduced the specific volume and width/height ratio of steamed bread but increased the brightness index, yellowish color, and color difference; improved the internal structure; and maintained the other sensory parameters and total score. Polydextrose addition decreased the peak, trough, final, breakdown, and setback viscosity of the pasting of wheat flour suspension solutions but increased the pasting temperature. Polydextrose additions significantly reduced the enthalpy of gelatinization and the aging rate of flour paste but increased the peak temperature of gelatinization. A Mixolab revealed that, with increases in the amount of added polydextrose, the dough’s development time and heating rate increased, but the proteins weakened, and the peak torque of gelatinization, starch breakdown, and starch setback torque all decreased. Polydextrose additions increased the crystalline regions of starch, the interaction between proteins and starch, and the β-sheet percentage of wheat dough without yeast and of steamed bread. The amorphous regions of starch were increased in dough through adding polydextrose, but they were decreased in steamed bread. Further, 3–10%of polydextrose addition decreased the random coils, α-helixes, and β-turns in dough, but the 3–7% polydextrose addition maintained or increased these conformations in steamed bread, while 10% polydextrose decreased them. In unfermented dough, as a hydrogel, the 5–7% polydextrose addition resulted in the formation of a continuous three-dimensional network structure with certain adhesiveness and elasticity, with increases in the porosity and gas-holding capacity of the product. Moreover, the 10% polydextrose addition further increased the viscosity, freshness, and looseness of the dough, with smaller and more numerous holes and indistinct boundaries between starch granules. These results indicate that the 3–10% polydextrose addition increases the chewiness and freshness of steamed bread by improving the gluten network structure. This study will promote the addition of polydextrose in steamed bread to improve shelf-life and dietary fiber contents. Full article

The purpose of this study was to demonstrate the feasibility of using spheroidal cellulose powders with different particle sizes (2 and 7 µm) in face creams and to evaluate their effect on selected physicochemical and performance properties of these products. A series of prototypes of facial creams with spheroidal cellulose were prepared. The following tests were carried out: stability, dynamic viscosity, texture analysis, degree of skin hydration, and evaluation of sensory appeal by consumers. It was observed that none of the creams showed instability over time. The addition of powdered spheroidal cellulose was found to increase dynamic viscosity and hardness and reduce the adhesion strength of the tested emulsions to the base face cream. A positive effect of the presence of polymeric raw materials on the level of skin hydration was observed. The most favorable results were obtained for the E4 cream prototype containing spheroidal powders of both 2 and 7 µm particle size at a weight ratio of 2.5 to 2.5. In addition, according to the members of the sensory panel, the E4 face cream was best evaluated and showed sensory benefits. The study concluded that spheroidal cellulose powders are a promising biodegradable alternative to microplastics in cosmetics. Full article

Vegetable oils can serve as a fundamental raw material for formulating lubricants due to their exceptional lubricating properties, which are indicated by viscosity indexes greater than 100. Vegetable oils, due to their unsaturated fatty acids with one or more double bonds, have two significant drawbacks: low oxidation stability and poor performance in low temperatures. The oxidative stability of sunflower and soybean oils was evaluated and correlated with the unsaturation degree calculated based on fatty acid profiles. Different percentages of piperine, curcumin, gingerol, and proanthocyanidin (0.5, 1, 2, and 3 wt.%) have been tested as potential bio-additives for sunflower and soybean oils. All four bio-additives have been observed to enhance oxidation resistance, with gingerol being the most effective, followed by curcumin, piperine, and proanthocyanidin. Bio-additives’ effectiveness increases when applied to bio-oils with lower degrees of unsaturation, such as soybean oil. Adding gingerol significantly enhances the induction period, increasing it by about 10 times for soybean oil and 6 times for sunflower oil. This suggests that gingerol can effectively prolong the induction period of both oils. Full article

This study explores the application of three fermented plant materials—wheat, acorns, and sorghum—in couscous preparation, as well as their impact on its properties. A survey was conducted in some localities in Algeria. The aim is to reproduce the diagrams for the manufacture of different types of couscous incorporated with fermented materials and to evaluate the pasting properties, culinary qualities, and microstructure of each type of couscous produced. The survey identified four couscous formulations made with durum wheat semolina: couscous 1 (4% sorghum, 4% wheat, 8% acorns), couscous 2 (8% acorns), couscous 3 (0.8% sorghum, 6% acorns), and couscous 4 (4% wheat, 4% acorns). A comparative study of the four types of couscous showed significant differences in their physicochemical and microstructural properties. Formulations C3 and C4 showed the best functional performance among all the couscous samples studied. In terms of the swelling index, measured at 25 °C and 95 °C, C3 reached 131.11% and 165.55%, respectively, while C4 recorded 124.9% and 157.0%. Furthermore, these two formulations had the highest viscosity values: initial viscosity of 25 mPas (C3) and 27 mPas (C4), maximum viscosity of 31 mPas (C3) and 30 mPas (C4), and final viscosity of 49 mPas (C3) and 46 mPas (C4). Analysis of the cooking loss revealed higher values for couscous 1 and 2. The microstructure of couscous 2 revealed the presence of native starch particles, open porosity, and a state of partial gelatinization. The study revealed that formulations C3 and C4 significantly (p < 0.05) impact couscous structure by enhancing functionality while preserving quality. It also maintained ancestral knowledge and offered valuable insights for future industrial applications. Full article

The goal of this study is to evaluate how the inclusion of synthetic wax, added in 0.5% increments from 1.5% to 3.5%, affects the characteristics of PMB 45/80-65 (polymer-modified bitumen) during both short-term (RTFOT) and long-term (PAV) aging processes. Tests were carried out to assess the fundamental properties of the binder, leading to the determination of the penetration index (PI) and the plasticity range (PR). The binder’s properties were examined at below-freezing operating temperatures, with creep stiffness measured using a bent beam rheometer (BBR) at −10 °C, −16° C, −22 °C, and −28 °C. The rheological properties of the asphaltenes were evaluated based on both linear and nonlinear viscoelasticity. The experimental study explored temperature effects on the rheological properties of composite materials using a DSR dynamic shear rheometer at 40 °C, 60 °C, and 80 °C over a frequency range of 0.005 to 10 Hz. The main parameters of interest were composite viscosity (η*) and zero shear viscosity (η₀). Viscoelastic parameters, including the dynamic modulus (G*) and phase shift angle (δ), were determined, and Black’s curves were used to illustrate the relationship between these parameters, where G*/sinδ was determined. The MSCR test was employed to investigate the impact of bitumen on the asphalt mixture’s resistance to permanent deformation and to assess the degree and efficacy of asphalt modification. The test measured two parameters, irreversible creep compliance (J_nr) and recovery (R), under stress levels of 0.1 kPa (LVE) and 3.2 kPa (N-LVE). The Christensen–Anderson–Marasteanu model was used to describe the bitumen behavior during binder aging, as reflected in the rheological study results. Ultimately, this study revealed that synthetic wax influences the rheological properties of PMB 45/80-65 polymer bitumen. Specifically, it mitigated the stiffness reduction in modified bitumen caused by polymer degradation during aging at an amount less than 2.5% of synthetic wax. Full article

This study aimed to assess the viability of a new gelling agent, formed by a combination of disodium 5-guanylate and lactic acid, as a potential substitute for conventional hydrocolloids in yogurt production. Six different yogurt samples containing novel gel (combination of lactic acid and disodium 5-guanylate), disodium 5-guanylate, gelatin, agar-agar, lactic acid, and a control yogurt without any hydrocolloid or other additives, were studied. As expected, all the yogurt samples exhibited shear-thinning behavior. The novel gel yogurt, when compared to the control yogurt, displayed similar viscosity at a low shear rate of 4.5 s⁻¹ (mimicking the shearing during manual scooping with a spoon) and lower viscosity at a shear rate of 60.8 s⁻¹ (mimicking the agitation in the mouth). Notably, the novel gel yogurt demonstrated a lower flow behavior index (0.13 vs. 0.40 on day 1), reduced syneresis (23.37% vs. 33.75%), and had a higher consistency coefficient (9.2 vs. 7.25 on day 1) compared to the control yogurt. The novel gel yogurt exhibited superior rupture strength compared to yogurt with other hydrocolloids, such as gelatin and agar-agar, and similar brittleness to yogurt with gelatin. Microstructural analysis revealed an aggregated and compact protein network in the novel gel yogurt, analogous to the yogurt with gelatin. Sensory evaluations indicated no significant differences between the control and the novel gel yogurt. Therefore, the novel gelling agent studied can serve as a cost-effective alternative in yogurt production, compared to conventional hydrocolloids that are in short supply, in high demand, and expensive in the market. Full article

This study presents an innovative approach to quantifying uncertainty in Herschel–Bulkley (H-B) fluid flow through rectangular ducts, analyzing four scenarios: uncertain apparent viscosity (Case I), uncertain pressure gradient (Case II), uncertain boundary conditions (Case III) and uncertain apparent viscosity and pressure gradient (Case IV). Using the stochastic finite difference with homogeneous chaos (SFDHC) method, we produce probability density functions (PDFs) of fluid velocity with exceptional computational efficiency (243 times faster), matching the accuracy of Monte Carlo simulation (MCS). Key statistics and maximum velocity PDFs are tabulated and visualized for each case. Mean velocity shows minimal variation in Cases I, III, and IV, but maximum velocity fluctuates significantly in Case I (63.95–187.45% of mean), Case II (50.15–156.68%), and Case IV (63.70–185.53% of mean), vital for duct design and analysis. Examining the effects of different parameters, the SFDHC method’s rapid convergence reveals the fluid behavior index as the primary driver of maximum stochastic velocity, followed by aspect ratio and yield stress. These findings enhance applications in drilling fluid management, biomedical modeling (e.g., blood flow in vascular networks), and industrial processes involving non-Newtonian fluids, such as paints and slurries, providing a robust tool for advancing understanding and managing uncertainty in complex fluid dynamics. Full article