Forecasting the rheological state properties of self-compacting concrete mixes using the response surface methodology technique for sustainable structural concreting.

It is structurally pertinent to understudy the important roles the self-compacting concrete (SCC) yield stress and plastic viscosity play in maintaining the rheological state of the concrete to flow. It is also important to understand that different concrete mixes with varying proportions of fine to coarse aggregate ratio and their nominal sizes produce different and corresponding flow- and fill-abilities, which are functions of the yield stress/plastic viscosity state conditions of the studied concrete. These factors have necessitated the development of regression models, which propose optimal rheological state behavior of SCC to ensure a more sustainable concreting. In this research paper on forecasting the rheological state properties of self-compacting concrete (SCC) mixes by using the response surface methodology (RSM) technique, the influence of nominal sizes of the coarse aggregate has been studied in the concrete mixes, which produced experimental mix entries. A total of eighty-four (84) concrete mixes were collected, sorted and split into training and validation sets to model the plastic viscosity and the yield stress of the SCC. In the field applications, the influence of the sampling sizes on the rheological properties of the concrete cannot be overstretched due to the importance of flow consistency in SCC in order to achieve effective workability. The RSM is a symbolic regression analysis which has proven to exercise the capacity to propose highly performable engineering relationships. At the end of the model exercise, it was found that the RSM proposed a closed-form parametric relationship between the outputs (plastic viscosity and yield stress) and the studied independent variables (the concrete components). This expression can be applied in the design and production of SCC with performance accuracies of above 95% and 90%, respectively. Also, the RSM produced graphical prediction of the plastic viscosity and yield stress at the optimized state conditions with respect to the measured variables, which could be useful in monitoring the performance of the concrete in practice and its overtime assessment. Generally, the production of SCC for field applications are justified by the components in this study and experimental entries beyond which the parametric relations and their accuracies are to be reverified.

Flow properties of single origin chocolates: Effect of product formulation and particle size.

The objective of this research was to evaluate changes in flow behavior of chocolate during chocolate grinding using a stone grinder as affected by chocolate formulation. Three different types of chocolates were evaluated. Two chocolates without milk added (70% chocolate) and two chocolates with milk added and with different amounts of cocoa nibs (30% chocolate and 14% chocolate) were tested. For the 70% chocolates, nibs of two different origins were used; therefore, a total of four samples were evaluated. Chocolates were processed in a stone grinder, and samples were taken as a function of grinding time. For each timepoint, the flow behavior of the samples was measured using a rotational rheometer and fitted to the Casson model. Particle size was measured using a laser scattering instrument. Results showed that yield stress increased linearly while the Casson plastic viscosity decreased exponentially with grinding time (smaller particles). Particle size distribution of the chocolates showed a prominent bimodal distribution for short grinding times (∼9 h) with small (∼15 µm) and large (∼100 µm) particles; with longer grinding time, the population of larger particles decreased. Yield stress values were higher for the 70% chocolate, but they were not very different between the two milk chocolates tested. The Casson plastic viscosity was greatest for the 70% chocolate, followed by the 30% chocolate. The 14% chocolate had the lowest Casson plastic viscosity. Changes of Casson plastic viscosity with particle size were more evident for the dark chocolates compared to the milk ones. These results are helpful to small chocolate producers who need better understanding of how the formulation and grinding of chocolate affect its flow behavior, which will ultimately affect chocolate handling during production.

A near-infrared fluorescent probe for differentiating cancer cells from normal cells and early diagnosis of liver cirrhosis.

BACKGROUND: Cirrhosis represents the terminal stage of liver disease progression and timely intervention in a diseased liver can enhance the likelihood of recovery. Viscosity, a crucial parameter of the cellular microenvironment, is intricately linked to the advancement of cirrhosis. However, viscosity monitoring still faces significant challenges in achieving non-invasive and rapid early diagnosis of cirrhosis. Near-infrared (NIR) fluorescence imaging has the advantages of high sensitivity, non-destructive detection, and ignoring background fluorescence interference, plays an important role in diagnosing and treating various biological diseases. Hence, monitoring cellular viscosity changes with NIR fluorescence probe holds great significance in the early diagnosis of cirrhosis. RESULTS: In this study, the NIR fluorescence probe based on the intramolecular charge transfer (TICT) mechanism was developed for imaging applications in mouse model of liver cirrhosis. A molecular rotor-type viscosity-responsive probe was synthesized by linking dioxanthracene groups via carbon-carbon double bonds. The probe demonstrated remarkable sensitivity, high selectivity and photostability, with its responsiveness to viscosity largely unaffected by factors such as polarity, pH, and interfering ions. The probe could effectively detect various drug-induced changes in cellular viscosity, enabling the differentiation between normal cells and cancerous cells. Furthermore, the enhanced tissue penetration capabilities of probe facilitated its successful application in mouse model of liver cirrhosis, allowing for the assessment of liver disease severity based on fluorescence intensity and providing a powerful tool for early diagnosis of cirrhosis. SIGNIFICANCE: A NIR viscosity-sensitive fluorescent probe was specifically designed to effectively monitor alterations in cellular and organ viscosity, which could advance the understanding of the biological characteristics of cancer and provide theoretical support for the early diagnosis of cirrhosis. Overall, this probe held immense potential in monitoring viscosity-related conditions, expanding the range of biomedical tools available.

Viscoelastic, Optical, and Surgical Properties of Vitreous Body Replacement Hydrogels After Aging Compared to Porcine Vitreous Bodies And Silicone Oils.

Purpose: First- (monomers), second- (pre-gelated), and third- (in situ gelating after injection) generation hydrogels were previously introduced to replace the vitreous body after vitrectomy surgery. In this study, we evaluated the surgical, optical, and viscoelastic properties of vitreous body replacement hydrogels before and after an accelerated aging protocol previously applied to intraocular implants. Methods: Measurements of injection force, removal speed using a clinically established vitrectomy setup, as well as evaluation of forward light scattering and viscoelastic properties before and after an accelerated aging protocol were conducted. Results were compared to porcine and human vitreous bodies, as well as currently clinically applied lighter- and heavier-than-water silicone oils. Results: Removal speed of all tested hydrogels is substantially lower than the removal speed of porcine vitreous body (0.2 g/min vs. 2.7 g/min for the best performing hydrogel and porcine vitreous body, respectively). Forward light scattering in second-generation vitreous body replacement hydrogels was higher after the aging process than the straylight of the average 70-year-old vitreous body (9.4 vs. 5.5 deg2/sr, respectively). The viscoelastic properties of all hydrogels did not change in a clinically meaningful manner; however, trends toward greater stiffness and greater elasticity after aging were apparent. Conclusions: This study demonstrates surgical weaknesses of the hydrogels that need to be addressed before clinical use, especially low removal speed. Pre-linked hydrogels (second-generation) showed inferior performance regarding surgical properties compared to in situ gelating hydrogels (third-generation). Translational Relevance: This study highlights possible pitfalls regarding surgical and optical properties when applying vitreous replacement hydrogels clinically.

Genistein transfersome-embedded topical delivery system for skin melanoma treatment: in vitro and ex vivo evaluations.

Skin melanoma is considered the most dangerous form of skin cancer due to its association with high risk of metastasis, high mortality rate and high resistance to different treatment options. Genistein is a natural isoflavonoid with known chemotherapeutic activity. Unfortunately, it has low bioavailability due to its poor aqueous solubility and excessive metabolism. In the current study, genistein was incorporated into transferosomal hydrogel to improve its bioavailability. The prepared transferosomal formulations were characterized regarding: particle size; polydispersity index; zeta potential; encapsulation efficiency; TEM; FTIR; DSC; XRD; in vitro drug release; viscosity; pH; ex vivo anti-tumor activity on 3D skin melanoma spheroids and 1-year stability study at different storage temperatures. The optimized formulation has high encapsulation efficiency with an excellent particle size that will facilitate its penetration through the skin. The transfersomes have a spherical shape with sustained drug release profile. The anti-tumor activity evaluation of genistein transfersome revealed that genistein is a potent chemotherapeutic agent with enhanced penetration ability through the melanoma spheroids when incorporated into transfersomes. Stability study results demonstrate the high physical and chemical stability of our formulations. All these outcomes provide evidence that our genistein transferosomal hydrogel is a promising treatment option for skin melanoma.

Experiment and analysis of physical, mechanical, and viscoelastic properties of the roots and stalks of green leafy vegetables.

Green leafy vegetables are an essential component of Chinese leafy vegetables. Due to their crisp stems and tender leaves, orderly harvester generally causes significant mechanical clamping damage. The physical and mechanical properties of green leafy vegetables are one of the important basis to design the orderly harvester. At the same time, they provide important parameters for the simulation and optimization of harvester. So, this paper measured the physical characteristic parameters of roots and stems of green leafy vegetables. Then, based on the TMS-Pro texture analyzer, the elasticity modulus of the roots and stems of green leafy vegetables were measured. The static friction coefficient, dynamic friction coefficient, and restitution coefficient of green leafy vegetables root-root, stem-stem, root-steel, and stem-steel were measured separately using a combination method of inclined plane and high-speed photography. Uniaxial compression creep experiments were carried out on whole and single leaf of green leafy vegetables using the TA.XT plus C universal testing machine. The constitutive equation of the four-element Burgers model was used to fit the deformation curve of the sample with time during the constant-pressure loading stage. The fitting determination coefficients R2 were all higher than 0.996, which verified the reasonable validity of the selected model. The above experimental results provide a parameter basis and theoretical support for the design and discrete element simulation optimization of orderly harvester critical components of green leafy vegetables.

Comparison of four rheological models for estimating viscosity and rheological parameters of microwave treated Basil seed gum.

Dispersion of Basil seed gum has high viscosity and exhibits shear-thinning behavior. This study aimed to analyze the influence of microwave treatment (MT) at various time intervals (0, 1, 2, and 3 min) on the viscosity and rheological behavior of Basil seed gum dispersion (0.5%, w/v). The finding of this study revealed that the apparent viscosity of Basil seed gum dispersion (non-treated dispersion) reduced from 0.330 Pa.s to 0.068 Pa.s as the shear rate (SR) increased from 12.2 s-1 to 171.2 s-1. Additionally, the apparent viscosity of the Basil seed gum dispersion reduced from 0.173 Pa.s to 0.100 Pa.s as the MT time increased from 0 to 3 min (SR = 61 s-1). The rheological properties of gum dispersion were successfully modeled using Power law (PL), Bingham, Herschel-Bulkley (HB), and Casson models, and the PL model was the best one for describing the behavior of Basil seed gum dispersion. The PL model showed an excellent performance with the maximum r-value (mean r-value = 0.942) and the minimum sum of squared error (SSE) values (mean SSE value = 5.265) and root mean square error (RMSE) values (mean RMSE value = 0.624) for all gum dispersion. MT had a considerable effect on the changes in the consistency coefficient (k-value) and flow behavior index (n-value) of Basil seed gum dispersion (p < 0.05). The k-value of Basil seed gum dispersion decreased significantly from 3.149 Pa.sn to 1.153 Pa.sn (p < 0.05) with increasing MT time from 0 to 3 min. The n-value of Basil seed gum dispersion increased significantly from 0.25 to 0.42 (p < 0.05) as the MT time increased. The Bingham plastic viscosity of Basil seed gum dispersion increased significantly from 0.029 Pa.s to 0.039 Pa.s (p < 0.05) while the duration of MT increased. The Casson yield stress of Basil seed gum dispersion notably reduced from 5.010 Pa to 2.165 Pa (p < 0.05) with increasing MT time from 0 to 3 min.

Comparison of thermal, rheological properties of Finnish Pinus sp. and Brazilian Eucalyptus sp. black liquors and their impact on recovery units.

Black liquor (BL) is the major bioproduct and biomass fuel in pulp mill processes. However, the high viscosity of BL makes it a challenging material to work with, resulting in issues with evaporators and heat exchangers during its transport and processing. The thermal and rheological properties of BLs from Pinus sp. (PBL) and Eucalyptus sp. (EBL) were studied. FTIR spectra revealed the presence of the characteristic functional groups and the chemical composition in liquors. TGA/DTG curves showed three characteristic degradation stages related to evaporation of water, pyrolysis of organic groups, and condensation of char. Rheologically, liquors are classified as non-Newtonian and with comportment pseudoplastic. Their rheological dynamic shear properties included a linear viscoelastic region up to 1% shear strain, while frequency sweeps showed that storage modulus (G') > loss modulus (G''), thus confirming the solid-like behavior of both BLs. The rheological study demonstrated that increasing the temperature and oscillatory deformations of PBL and EBL decreased their degree of viscoelasticity, which could favor their pumping and handling within the pulp mill, as well as the droplet formation and swelling characteristics in the recovery furnace.

Effects of dispersing media on the rheological and tribological properties of basil seed mucilage-based thickened liquids.

The development of thickening powders for the management of dysphagia is imperative due to the rapid growth of aging population and prevalence of the dysphagia. One promising thickening agent that can be used to formulate dysphagia diets is basil seed mucilage (BSM). This work investigates the effects of dispersing media, including water, milk, skim milk, and apple juice, on the rheological and tribological properties of the BSM-thickened liquids. Shear rheology results revealed that the thickening ability of BSM in these media in ascending order is milk < skim milk ≈ apple juice < water. On the other hand, extensional rheology demonstrated that the longest filament breakup time was observed when BSM was dissolved in milk, followed by skim milk, water, and apple juice. Furthermore, tribological measurements showed varying lubrication behavior, depending on the BSM concentration and dispersing media. Dissolution of BSM in apple juice resulted in the most superior lubrication property compared with that in other dispersing media. Overall, this study provides insights on BSM's application as a novel gum-based thickening powder in a range of beverages and emphasizes how important it is for consumers to have clear guidance for the use of BSM in dysphagia management.

Correlation of rheology and oral tribology with sensory perception of commercial hazelnut and cocoa-based spreads.

This study examined the effects of spread formulation and the structural/lubricant properties of six different commercial hazelnut and cocoa spreads on sensory perception. Rheology, tribology, and quantitative descriptive analysis (QDA) was assessed by also evaluating the correlation coefficients between the quality descriptor and the rheological and textural parameters. The viscosity was evaluated at different temperatures to better simulate conditions before and after ingestion. Tribological analysis was executed at 37°C to mimic the human oral cavity. The effect of saliva presence and the number of runs on tribological behaviors was investigated. Moreover, textural, calorimetric, and particle size distribution measurements were performed to reinforce the correlation between structural/thermal parameters (e.g., firmness, stickiness, sugar melting point) and sensory aspects. "Visual viscosity," defined as a sensory attribute evaluated prior to consumption, negatively correlated with apparent viscosity measured at 20°C and 10 s-1, whereas "body," defined during oral processing and related to creaminess, positively correlated with apparent viscosity measured at 37°C and 50 s-1. These attributes were mainly influenced by particulate microstructure and solid volume fraction within the formulation. Textural stickiness positively correlated with sensory "adhesiveness" and was related to fat composition and milk powder addition, while "sweetness" was related to sucrose content and sugar melting enthalpy. Tribological data provided meaningful information related to particle-derived attributes, as well as after-coating perception (fattiness/oiliness), thus better predicting food evolution during oral consumption.

Impact of saliva incorporation on the rheological properties of in vitro gastric contents formulated from sour cream.

Rheological properties of gastric contents depend on the food ingested, and on the volume and composition of secretions from the host, which may vary. This study investigates the impact of saliva regular incorporation in the stomach after a meal on the rheological properties of gastric contents, considering two levels of salivary flow (low = 0.5 and high = 1.5 mL/min). In vitro chymes were obtained by mixing sour cream, simulated gastric fluid, two different volumes of oral fluid (at-rest human saliva, SSF for Simulated Salivary Fluid or water) and adjusting pH at 3. Chymes samples were characterized at 37°C for their particle size and rheological properties. Overall, particle size distribution was not different between samples: incorporating a larger volume of saliva resulted in more heterogeneity, but the surface area moment D[3,2] and volume moment D[4,3] did not differ significantly with the oral fluid type. Shear viscosity of chyme samples was higher when saliva was incorporated, in comparison with water or SSF. In addition, as shown from data extracted at γ ̇ $$ \dot{\gamma} $$ = 20 s-1 the higher the fluid volume the lower the shear viscosity, which is attributed to a dilution effect. However, this dilution effect was attenuated in the case of saliva, most likely due to its composition in organic compounds (e.g., mucins) contributing to the rheological properties of this biological fluid. In these in vitro conditions, both saliva and the salivation rate had a significant but slight impact on the rheological properties of gastric contents (of the order of 1-5 mPa s at γ ̇ $$ \dot{\gamma} $$ = 20 s-1).

Temperatures above 37°C increase virulence of a convergent Klebsiella pneumoniae sequence type 307 strain.

Background: Convergence of Klebsiella pneumoniae (KP) pathotypes has been increasingly reported in recent years. These pathogens combine features of both multidrug-resistant and hypervirulent KP. However, clinically used indicators for hypervirulent KP identification, such as hypermucoviscosity, appear to be differentially expressed in convergent KP, potential outbreak clones are difficult to identify. We aimed to fill such knowledge gaps by investigating the temperature dependence of hypermucoviscosity and virulence in a convergent KP strain isolated during a clonal outbreak and belonging to the high-risk sequence type (ST)307. Methods: Hypermucoviscosity, biofilm formation, and mortality rates in Galleria mellonella larvae were examined at different temperatures (room temperature, 28°C, 37°C, 40°C and 42°C) and with various phenotypic experiments including electron microscopy. The underlying mechanisms of the phenotypic changes were explored via qPCR analysis to evaluate plasmid copy numbers, and transcriptomics. Results: Our results show a temperature-dependent switch above 37°C towards a hypermucoviscous phenotype, consistent with increased biofilm formation and in vivo mortality, possibly reflecting a bacterial response to fever-like conditions. Furthermore, we observed an increase in plasmid copy number for a hybrid plasmid harboring carbapenemase and rmpA genes. However, transcriptomic analysis revealed no changes in rmpA expression at higher temperatures, suggesting alternative regulatory pathways. Conclusion: This study not only elucidates the impact of elevated temperatures on hypermucoviscosity and virulence in convergent KP but also sheds light on previously unrecognized aspects of its adaptive behavior, underscoring its resilience to changing environments.

[Examination of the Thermal Stability and Swallowing Safety of a Self-Developed Enteral Nutrition Thickening Agent]. / è‡ªåˆ¶è‚ å† è¥å »æ¶²å¢žç¨ å‰‚çš„çƒ­ç¨³å®šæ€§åŠåžå’½å®‰å ¨æ€§æŽ¢ç´¢.

Objective: To experimentally validate the effects of a self-developed heat-stable thickening agent on the textual characteristics of enteral nutrition solutions of standard concentration and its applicability in improving dysphagia. Methods: A gradient of different doses of the self-developed thickening agent (1.0 g, 1.5 g, 2.0 g, 2.5 g, and3.0 g) and three commonly used commercial thickeners were mixed with 23.391 g of a complete nutrition formula powder dissolved in 85 mL of purified water to prepare 100 mL standard concentration nutrition solutions. The textual parameters (cohesiveness, viscosity, thickness, and hardness) of these nutrition solutions were measured using a texture analyzer at various temperature gradients (20 ℃, 40 ℃, 60 ℃, and 80 ℃) to compare their thermal stability. A dysphagia rat model was created via epiglottectomy to explore the effects of the thickener on lung tissue damage scores and levels of inflammatory markers. The rats were divided into a test intervention group, a positive control group, a negative control group, and a blank control group (no surgery and normal feeding after fasting for one day), with 15 rats in each group. After fasting for one day post-surgery, the test intervention group was fed with the standard concentration nutrition solution thickened with the self-developed thickener, while the positive control group was given a standard concentration nutrition solution thickened with product 3, and the negative control group was fed a normal diet. All groups were fed for two weeks with food dyed with food-grade green dye. General conditions, body mass, and food intake were observed and recorded. After two weeks, abdominal aorta blood was collected, and heart, liver, spleen, lung, and kidney tissues were harvested and weighed to calculate the lung tissue organ coefficient. The organ conditions were evaluated using routine H&E staining, and lung damage was semi-quantitatively analyzed based on the Mikawa scoring criteria. Blood supernatants were collected to measure the total serum protein and albumin levels to determine the nutritional status of the rats. The expression of IL-6 and TNF-α genes in lung tissues was measured by RT-qPCR. IL-6 and TNF-α protein expression levels in lung tissues, lung tissue homogenate, and serum were measured by ELISA. The aspiration incidence rate was calculated. Results: Within the dosage range of 1.0 g to 3.0 g, the self-developed thickener in the test samples exhibited superior thermal stability in cohesiveness compared to the three commercially available thickeners, with a statistically significant difference (P<0.01). The differences in the thermal stability of viscosity and hardness between the self-developed thickener and the three commercially available thickeners were not statistically significant. The viscosity stability was optimal for the self-developed thickener, followed by the commercially available thickeners 1 and 3, with thickeners 2 being the least stable, though the differences were not statistically significant (P>0.05). Product 1 showed the best thermal stability in thickness, followed by the self-developed thickener and product 2, while the product 3 exhibited the worst performance, with the difference being statistically significant (P<0.01). The self-developed thickener had the best thermal stability in hardness at temperatures ranging from 20℃ to 80 ℃, followed by products 1 and 2, with product 3 being the least stable. However, the differences were not statistically significant (P>0.05). Animal experiment results indicated that the body weight gain in the positive control group and the test intervention group was lower than that in the blank and negative control groups (P<0.01). The spleen coefficient of the intervention group was lower than that of the positive control group and the blank control group (P<0.01), while the heart, liver, and kidney coefficients were lower than those of the blank control group (P<0.01). The differences in the lung coefficient of the intervention group and those of the other three groups were no statistically significant. Levels of TP and ALB in the test intervention group, the positive control group, and the negative control group were all lower than those in the blank control group, with statistically significant differences (P<0.01). ELISA results showed that serum IL-6 levels in the blank and test intervention groups were lower than those in the negative and positive control groups (P<0.05), while the difference in the other indicators across the four groups were not statistically significant (P>0.05). There were no statistically significant differences among the four groups in terms of lung tissue damage pathology scores, or in the levels of IL-6 and TNF-α gene expression in lung tissues. The aspiration incidence rate was 0% in all groups. Conclusion: The self-developed enteral nutrition thickening agent demonstrated excellent thermal stability and swallowing safety. Further research to explore its application in patients with dysphagia is warranted.

Application of supercritical carbon dioxide to enhance the aroma of whole sorghum flour for use in 3D printing of sorghum cookies.

Sorghum is a promising ingredient for new food products due to its high fiber content, slow digestibility, drought resistance, and gluten-free nature. One of the main challenges in sorghum-based products is the unpleasant aroma compounds found in grain sorghum. Therefore, in this study, sorghum flour was treated via supercritical carbon dioxide (SC-CO2) to remove undesired aroma compounds. The resulting SC-CO2-treated flours were used to generate dough for 3D food printing. At the optimized conditions, sorghum cookies were 3D-printed using 60 % water and a nozzle diameter of 1.5 mm. All dough samples produced with untreated and SC-CO2-treated sorghum flours exhibited shear-thinning behavior. Changing the treatment pressure (8-15 MPa) or temperature (40-60 °C) did not significantly affect the viscosity of the dough samples. Moreover, the sorghum cookie doughs had higher G' and G″ values after the SC-CO2 treatments (G' > G″). Doughs generated from flours treated at 15 MPa - 40 °C and 8 MPa - 60 °C showed lower adhesiveness compared to the ones produced from untreated flour, whereas 15 MPa - 60 °C treatment did not affect the adhesiveness. After baking, the 3D-printed cookies from SC-CO2-treated flour exhibited significantly lower redness (a*), but the hardness of the cookies was not affected by SC-CO2 treatment. Overall, the SC-CO2 treatment of sorghum flour did not negatively affect the quality parameters of the 3D-printed cookies while enhancing the aroma of the flour.

Comparative Analysis of Maize Physico-Chemical Parameters and Mycotoxin Levels in Dual Environments.

Maize (Zea mays L.) stands as a vital staple food globally, holding significant nutritional and economic value. However, its susceptibility to mycotoxin contamination under stressful environmental conditions poses a considerable concern. This study aimed to assess the quality and pasting characteristics of maize varieties across two distinct regions and examine the occurrence of mycotoxins influenced by climatic factors. Five maize varieties were cultivated in triplicate in the Golegã and Coruche regions. The nutritional composition (protein, fat, fiber, ash, starch, and lutein), pasting properties, and mycotoxin levels were evaluated. A statistical analysis revealed notable differences in the nutritional profiles of the maize varieties between the two regions, particularly in the protein and lutein content. The peak viscosity ranged from 6430 to 8599 cP and from 4548 to 8178 cP in the maize varieties from the Coruche and Golegã regions, respectively. Additionally, a significant correlation was observed between the climatic conditions and the grain nutritional quality components (p < 0.05). The M variety showed the highest ash content, protein content, final viscosity, and setback viscosity and the lowest peak viscosity. The Y variety revealed the lowest fat, fiber, and lutein content and the maximum peak viscosity. The incidence of mycotoxins was notably higher in the varieties from Coruche, which was potentially attributable to higher temperatures and lower precipitation levels leading to more frequent drought conditions. Fumonisin B1 was detected in 58% of the varieties from Coruche and 33% of the samples from Golegã, while deoxynivalenol was found in 87% and 80% of the varieties from Coruche and Golegã, respectively. The H variety, which was harvested in Coruche, exhibited the highest number of fumonisins and higher amounts of protein, lutein, and fat, while fumonisins were not detected in the Golegã region, which was potentially influenced by the precipitation levels. The K variety revealed higher protein and lutein contents, a lower amount of fat, excellent pasting properties (a higher peak viscosity and holding strength and a lower peak time), and no fumonisins B1 or B2. This variety may be considered well adapted to higher temperatures and drier conditions, as verified in the Coruche region. In conclusion, our study underscored the profound impact of environmental factors on the quality and occurrence of mycotoxins in maize varieties.

Sequence-Based Viscosity Prediction for Rapid Antibody Engineering.

Through machine learning, identifying correlations between amino acid sequences of antibodies and their observed characteristics, we developed an internal viscosity prediction model to empower the rapid engineering of therapeutic antibody candidates. For a highly viscous anti-IL-13 monoclonal antibody, we used a structure-based rational design strategy to generate a list of variants that were hypothesized to mitigate viscosity. Our viscosity prediction tool was then used as a screen to cull virtually engineered variants with a probability of high viscosity while advancing those with a probability of low viscosity to production and testing. By combining the rational design engineering strategy with the in silico viscosity prediction screening step, we were able to efficiently improve the highly viscous anti-IL-13 candidate, successfully decreasing the viscosity at 150 mg/mL from 34 cP to 13 cP in a panel of 16 variants.

Preparation of Esterified Starches with Different Amylose Content and Their Blending with Polybutylene Succinate.

Three types of starch with different amylose content were esterified and blended with polybutylene succinate (PBS) to obtain esterified manioc starch/PBS (EMS/PBS), esterified corn starch/PBS (ECS/PBS), and esterified waxy corn starch/PBS (EWS/PBS) composites. The EMS/PBS and ECS/PBS composites with high amylose content displayed typical V-type crystal structures. The original crystals of EWS, which had low amylose content, were disrupted during the esterification process. EWS exhibited the strongest interaction with PBS and the most favorable interface compatibility. The pyrolysis temperature was in order of EMS/PBS < ECS/PBS < EWS/PBS. The elongation at break of the three blends was higher than that of pure PBS. The esterification and plasticization of the EWS/PBS composite were the most comprehensive. The EWS/PBS composite showed the lowest storage modulus (G') and complex viscosity (η*). The interfacial bonding force of the composite materials increased with more amylopectin, decreasing intermolecular forces and destroying crystal structures, which decreased G' and η* and increased toughness. The EWS/PBS composite, with the least amylose content, had the best hydrophobicity and degradation performance.

Toward the Establishment of a Harmonized Physicochemical Profiling Platform for Therapeutic Oligonucleotides: A Case Study for Aptamers Where the Higher-Order Structure Influences Physical Properties.

Oligonucleotides are short nucleic acids that serve as one of the most promising classes of drug modality. However, attempts to establish a physicochemical evaluation platform of oligonucleotides for acquiring a comprehensive view of their properties have been limited. As the chemical stability and the efficacy as well as the solution properties at a high concentration should be related to their higher-order structure and intra-/intermolecular interactions, their detailed understanding enables effective formulation development. Here, the higher-order structure and the thermodynamic stability of the thrombin-binding aptamer (TBA) and four modified TBAs, which have similar sequences but were expected to have different higher-order structures, were evaluated using ultraviolet spectroscopy (UV), circular dichroism (CD), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). Then, the relationship between the higher-order structure and the solution properties including solubility, viscosity, and stability was investigated. The impact of the higher-order structure on the antithrombin activity was also confirmed. The higher-order structure and intra-/intermolecular interactions of the oligonucleotides were affected by types of buffers because of different potassium concentrations, which are crucial for the formation of the G-quadruplex structure. Consequently, solution properties, such as solubility and viscosity, chemical stability, and antithrombin activity, were also influenced. Each instrumental analysis had a complemental role in investigating the higher-order structure of TBA and modified TBAs. The utility of each physicochemical characterization method during the preclinical developmental stages is also discussed.

Role of Unimers to Polymersomes Transition in Pluronic Blends for Controlled and Designated Drug Conveyance.

This study investigates the nanoscale self-assembly from mixtures of two symmetrical poly(ethylene oxide)-poly(propylene oxide)-pol(ethylene oxide) (PEO-PPO-PEO) block copolymers (BCPs) with different lengths of PEO blocks and similar PPO blocks. The blended BCPs (commercially known as Pluronic F88 and L81, with 80 and 10% PEO, respectively) exhibited rich phase behavior in an aqueous solution. The relative viscosity (ηrel) indicated significant variations in the flow behavior, ranging from fluidic to viscous, thereby suggesting a possible micellar growth or morphological transition. The tensiometric experiments provided insight into the intermolecular hydrophobic interactions at the liquid-air interface favoring the surface activity of mixed-system micellization. Dynamic light scattering (DLS) and small-angle neutron scattering (SANS) revealed the varied structural morphologies of these core-shell mixed micelles and polymersomes formed under different conditions. At a concentration of ≤5% w/v, Pluronic F88 exists as molecularly dissolved unimers or Gaussian chains. However, the addition of the very hydrophobic Pluronic L81, even at a much lower (<0.2%) concentration, induced micellization and promoted micellar growth/transition. These results were further substantiated through molecular dynamics (MD) simulations, employing a readily transferable coarse-grained (CG) molecular model grounded in the MARTINI force field with density and solvent-accessible surface area (SASA) profiles. These findings proved that F88 underwent micellar growth/transition in the presence of L81. Furthermore, the potential use of these Pluronic mixed micelles as nanocarriers for the anticancer drug quercetin (QCT) was explored. The spectral analysis provided insight into the enhanced solubility of QCT through the assessment of the standard free energy of solubilization (ΔG°), drug-loading efficiency (DL%), encapsulation efficiency (EE%), and partition coefficient (P). A detailed optimization of the drug release kinetics was presented by employing various kinetic models. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] MTT assay, a frequently used technique for assessing cytotoxicity in anticancer research, was used to gauge the effectiveness of these QCT-loaded mixed nanoaggregates.

Morphology, repulsion, and ordering of red blood cells in viscoelastic flows under confinement.

Red blood cells (RBC), the primary carriers of oxygen in the body, play a crucial role across several biomedical applications, while also being an essential model system of a deformable object in the microfluidics and soft matter fields. However, RBC behavior in viscoelastic liquids, which holds promise in enhancing microfluidic diagnostic applications, remains poorly studied. We here show that using viscoelastic polymer solutions as a suspending carrier causes changes in the clustering and shape of flowing RBC in microfluidic flows when compared to a standard Newtonian suspending liquid. Additionally, when the local RBC concentration increases to a point where hydrodynamic interactions take place, we observe the formation of equally-spaced RBC structures, resembling the viscoelasticity-driven ordered particles observed previously in the literature, thus providing the first experimental evidence of viscoelasticity-driven cell ordering. The observed RBC ordering, unaffected by polymer molecular architecture, persists as long as the surrounding medium exhibits shear-thinning, viscoelastic properties. Complementary numerical simulations reveal that viscoelasticity-induced repulsion between RBCs leads to equidistant structures, with shear-thinning modulating this effect. Our results open the way for the development of new biomedical technologies based on the use of viscoelastic liquids while also clarifying fundamental aspects related to multibody hydrodynamic interactions in viscoelastic microfluidic flows.