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Polar fluorinated arenes can promote organic free radical reactions, which have attracted scientists' interest in recent years. However, it is still unknown how these solvents interact weakly with organic radical molecules to influence their reactivity. In this study, we investigated how organic free radicals aggregate in five polar fluorocarbon solvents, and demonstrated that different substituents can influence their aggregation behaviors. In these solvents, small organic radicals with simple substituents maintain a homogeneous solution; however, radicals with substituents that form intermolecular hydrogen bonds or with long‐chain aliphatic hydrocarbons tend to aggregate in them, whereas substituents of long‐chain aliphatic hydrocarbons tend to promote aggregation better. The critical aggregation concentrations of these aggregates are measured by concentration‐dependent UV–visible spectroscopy. Their topological morphologies are all spherical based on TEM. The compactness and rotational motivation speed of radical molecules within these aggregates are determined by EPR spectroscopy. The particle sizes of these aggregates are determined by analyzing their cyclic voltammograms. Most excitingly, electrochemical experiments reveal that the aggregation behaviors of free radical molecules with intermolecular hydrogen bonds can significantly increase their catalytic rate for electro‐oxidizing benzyl alcohol in such a solvent. The results of this study indicate that in polar fluorinated arenes organic radical molecules' aggregation behaviors are related to their structures. This may provide guidelines for regulating organic radical reactivity in these solvents in the future. [ABSTRACT FROM AUTHOR]

Two mixed systems consisting of an anionic surfactant and a cationic surface-active ionic liquid were studied. The mixture of sodium octanesulfonate (SOS) and 1-decyl-3-methylimidazolium bromide ([C10mim]Br), and the mixture of SOS and 1-tetradecyl-3-methylimidazolium bromide ([C14mim]Br), were both investigated using surface tension measurement. The parameters, such as critical micelle concentration (cmc), surface tension at cmc (γcmc), surface pressure at cmc (Πcmc), maximum surface excess (Γmax) and minimum area per molecule (Amin), were obtained. The mixed micellar parameters including micellar mole fraction (X1m), micellar interaction parameters (βm) and activity coefficients (f1m), and f2m), were calculated by applying Rubingh's regular solution theory. The calculated parameters confirmed that there were strong synergy in all these mixed systems, and the interaction of SOS with [C14mim]Br was stronger than that with [C10mim]Br. Thermodynamic parameters for mixed monolayers and mixed micelles were calculated and discussed, which indicated that the mixed micelles were spontaneously formed and were thermodynamically stable systems. Turbidity measurement was conducted using spectrophotometry. The phase diagrams were plotted for each system based on visual observations and absorbance values. The mixed systems of SOS/[C10mim[Br and SOS/[C14mim[Br all exhibited three concentration regions: a low-concentration homogeneous solution region, a two-phase region, and a high-concentration homogeneous solution region. [ABSTRACT FROM AUTHOR]

RNA N6-methyladenosine (m6A), as the most abundant modification of messenger RNA, can modulate insect behaviors, but its specific roles in aggregation behaviors remain unexplored. Here, we conducted a comprehensive molecular and physiological characterization of the individual components of the methyltransferase and demethylase in the migratory locust Locusta migratoria. Our results demonstrated that METTL3, METTL14 and ALKBH5 were dominantly expressed in the brain and exhibited remarkable responses to crowding or isolation. The individual knockdown of methyltransferases (i.e., METTL3 and METTL14) promoted locust movement and conspecific attraction, whereas ALKBH5 knockdown induced a behavioral shift toward the solitary phase. Furthermore, global transcriptome profiles revealed that m6A modification could regulate the orchestration of gene expression to fine tune the behavioral aggregation of locusts. In summary, our in vivo characterization of the m6A functions in migratory locusts clearly demonstrated the crucial roles of the m6A pathway in effectively modulating aggregation behaviors. [ABSTRACT FROM AUTHOR]

Eucryptorrhynchus scrobiculatus (Motschulsky) (Coleoptera: Curculionidae) is a notorious pest of Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae). E. scrobiculatus adults typically aggregate under leaves and in soil crevices at the base of A. altissima in the field. We hypothesize that the environmental factors and conspecific signals determine their aggregation behavior. To test this, we investigated adult numbers in light-exposed and shaded areas of the sample trees and conducted experiments in both field and lab settings. Results revealed that (i) greater adult distribution in shaded areas; (ii) significant influence of temperature and illumination on aggregation tendency in the field; (iii) no gender-based difference in aggregation degree and maximum aggregation between light and dark; (iv) the host plant triggering the aggregation tendency, negatively affected in the absence; (v) the aggregation tendency of E. scrobiculatus weakened with the temperature gradually changing to ordinary temperature; and (vi) mutual attraction and chemical attraction between males and females. Thus, the aggregation behavior was influenced by factors including temperature, light intensity, host plant, and conspecific signals, but light's role was not obvious in the lab. [ABSTRACT FROM AUTHOR]

Salted egg yolks have a tender, loose, gritty, and oily texture and are commonly employed as fillings in baked goods. This study investigated the formation mechanism of egg yolk gels using three different pickling methods: NaCl, sucrose, and mixed groups. The results revealed that of these pickling methods, egg yolks pickled with the mixture had the lowest moisture content (11.59% at 25°C and 10.21% at 45°C), almost no free water content, and the highest hardness (19.11 N at 25°C and 31.01 N at 45°C). Intermolecular force measurements indicated that pickling with the mixture mitigated the surface hardening effect of sucrose and facilitated protein cross‐linking. Moreover, confocal laser scanning microscopy of the egg yolk gels pickled with the mixture displayed macromolecular aggregates and oil exudation, suggesting that this method partially disrupted the lipoprotein structure and notably promoted yolk protein aggregation and lipid release. Overall, egg yolks formed a dense gel via the mixed pickling method owing to the ionic concentration and dehydration effects. These findings show the impact of NaCl and sucrose in pickling egg yolks, providing a crucial foundation for developing innovative and desirable egg yolk products. Practical Application: This study introduces a novel pickling strategy that combines sucrose and NaCl for egg yolk processing. The egg yolk pickled using this method exhibited improved quality according to the evaluated textural characteristics, moisture distribution, and protein aggregation behavior. The findings may broaden the use of sucrose as a pickling agent for egg yolk processing and provide new ideas for developing and producing pickled eggs and other food products. [ABSTRACT FROM AUTHOR]

Abstract Polar fluorinated arenes can promote organic free radical reactions, which have attracted scientists’ interest in recent years. However, it is still unknown how these solvents interact weakly with organic radical molecules to influence their reactivity. In this study, we investigated how organic free radicals aggregate in five polar fluorocarbon solvents, and demonstrated that different substituents can influence their aggregation behaviors. In these solvents, small organic radicals with simple substituents maintain a homogeneous solution; however, radicals with substituents that form intermolecular hydrogen bonds or with long‐chain aliphatic hydrocarbons tend to aggregate in them, whereas substituents of long‐chain aliphatic hydrocarbons tend to promote aggregation better. The critical aggregation concentrations of these aggregates are measured by concentration‐dependent UV–visible spectroscopy. Their topological morphologies are all spherical based on TEM. The compactness and rotational motivation speed of radical molecules within these aggregates are determined by EPR spectroscopy. The particle sizes of these aggregates are determined by analyzing their cyclic voltammograms. Most excitingly, electrochemical experiments reveal that the aggregation behaviors of free radical molecules with intermolecular hydrogen bonds can significantly increase their catalytic rate for electro‐oxidizing benzyl alcohol in such a solvent. The results of this study indicate that in polar fluorinated arenes organic radical molecules’ aggregation behaviors are related to their structures. This may provide guidelines for regulating organic radical reactivity in these solvents in the future.

Abstract Background Halyomorpha halys Stål (Hemiptera: Pentatomidae), brown marmorated stink bug (BMSB), is a highly polyphagous invasive pest worldwide. It is also known to be a nuisance pest as it enters artificial structures, including human habitats, to overwinter and releases very unpleasant odours when disturbed. Overwintering populations can be trapped and killed collectively by targeting the aggregation behaviour of BMSB adults. However, efficient traps for catching overwinter population have not been yet developed and validated. A novel and effective trapping method would be to design shelter traps in the field that entice and mass-trap overwintering BMSB as they initiate to display their typical aggregation behavior and seek shelter in the traps. Methods In this study conducted in Northwestern China, we designed different BMSB overwintering shelter traps made of different materials (i.e., wood or corflute) and lock types (with/without lock, pyrometric or strip door lock) and tested their efficacy at two different sites and three different locations within sites. We also tested the efficacy of the traps with or without the presence of the BMSB aggregation pheromone. Results Although trapped BMSB numbers were generally low across all traps tested, the black corflute trap was found to attract the highest average number of BMSB males and females, followed by the wooden-made trap, the bee-hive box and finally the wooden-made locked trap, which attracted the lowest numbers of BMSB. The trapping efficacy was found to not be affected by experimental sites or locations nor by the presence of the BMSB aggregation pheromone lure. Conclusions Our results showed that traps made of black corflute with slit doors were generally preferred by overwintering BMSB. This preliminary proof-of-concept study provides valuable information for further improvement of novel overwintering traps that could be used to mass trap BMSB overwintering populations.

The potential of potassium chloride (KCl) to be used as a substitute for sodium chloride (NaCl) was studied by monitoring the effects of salt treatment on thermal behavior, aggregation kinetics, rheological properties, and protein conformational changes. The results show that the addition of KCl can improve solubility, reduce turbidity and particle size, and positively influence rheological parameters such as apparent viscosity, consistency coefficient (K value), and fluidity index (n). These changes indicate delayed thermal denaturation. In addition, KCl decreased the content of β-sheet and random coil structures and increased the content of α-helix and β-turn structures. The optimal results were obtained with 2% KCl addition, leading to an increase in Tp up to 85.09 °C. The correlation results showed that Tp was positively correlated with solubility, α-helix and β-turn but negatively correlated with ΔH, turbidity, β-sheet and random coil. Overall, compared to NaCl, 2% KCl is more effective in delaying the thermal aggregation of LWE, and these findings lay a solid theoretical foundation for the study of sodium substitutes in heat-resistant liquid egg products. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite impressive advances achieved in poly(3‐alkylthiophene)s (P3ATs) and P3AT‐based block copolymers (BCPs), the investigation into their ortho‐connected systems, poly(5‐alkylthiophene)s (P5ATs) and P5AT‐based BCPs is rather limited. Moreover, the aggregation behavior of P5ATs and their BCPs remains largely less understood. Herein, we report, for the first time, the judicious design and synthesis of a family of poly(5‐butylthiophene)‐block‐poly(5‐hexylthiophene) (P5BT‐b‐P5HT) BCPs with adjustable block ratios and reveal the effects of block ratios and thermal annealing process on their aggregated structures. Moreover, the optical properties of P5BT‐b‐P5HT BCPs have been investigated, which differs greatly from P3ATs. Overall, this work offers valuable insight into the aggregation and optical properties of P5AT‐based BCPs, strengthening our fundamental understanding of ortho‐connected P5AT systems. [ABSTRACT FROM AUTHOR]

This paper investigates the interactions and aggregation behavior of biosurfactants, sodium cholate (NaC) and sodium deoxycholate (NaDC) in aqueous solutions of Emtricitabine and Lamivudine (anti-HIV drugs). The study uses conductometry and UV–visible spectroscopy techniques to evaluate the critical micelle concentration (CMC) at different temperatures ranging from 298.15 K to 313.15 K with a variation of 5 K. The temperature dependence of the CMC was examined, and the stability of micelles was analyzed in light of the hydrophobic-hydrophilic interactions involved in this system. The CMC obtained from both the methods are in agreement. Various thermodynamic parameters, such as ∆ H m 0 , ∆ S m 0 and ∆ G m 0 have been estimated using a "pseudo-phase separation model" to understand the contribution of the chemical and de-solvation part in the micellization process. Furthermore, the enthalpy-entropy compensation plots validate the micellar stability of the studied systems. [ABSTRACT FROM AUTHOR]

New hexadecylpiperidinium surfactants, containing one or two butylcarbamate fragments, were synthesized. The antimicrobial activity, toxicity, aggregation behavior in aqueous solutions, and solubilization capacity of these surfactants towards the hydrophobic drug ibuprofen were characterized. These surfactants demonstrated a high antimicrobial activity against a wide range of pathogenic bacteria, including both Gram-positive and Gram-negative strains, as well as fungi. By forming mixed-micellar compositions of the cationic surfactant 1-CB(Bu)-P-16 and the nonionic surfactant Brij®35, highly functional and low-toxic formulations were obtained. Furthermore, the transition from mixed micelles to niosomes was accomplished, enhancing their potential as drug delivery systems. Niosomes were found to be less toxic compared to mixed micelles, while also increasing the solubility of ibuprofen in water. The modification of niosomes with cationic surfactants made it possible to increase the stability of the system and improve the solubility of the drug. The data obtained indicate that these new carbamate-containing hexadecylpiperidinium surfactants have significant potential in biomedical applications, particularly in the formulation of advanced drug delivery systems.

Model smart detergents for fruit washing were designed. Their physicochemical and functional properties were determined, with particular emphasis on the efficiency of removing pesticide residues. The specific behavior of nonionic surfactants near the so‐called cloud point was used in the design of the new smart detergent. The high performance of detergents was related to the temperature‐dependent aggregation behavior of surfactants. Liquid chromatography coupled with mass spectrometry (LC–MS/MS) was used to evaluate the washing efficiency. Four types of pesticides (boscalid, acetamiprid, pyraclostrobin and pendimethalin) were applied to apples and then washed with designed detergents. Washing efficiency was evaluated based on the change in pesticide content on the apple surface. Compared to water, the model detergents were found to be more effective in removing pesticide residues, reaching values above 80%. The detergents were also evaluated for skin effects and revealed a low potential for skin irritation. [ABSTRACT FROM AUTHOR]

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Our previous studies have shown that some Trichoderma fungi trigger aggregation behavior in Formosan subterranean termites, Coptotermes formosanus Shiraki. However, the mechanisms underlying the induction of termite aggregation by Trichoderma fungi remain unclear. Here, we found that the aqueous or acetone extract of Trichoderma asperellum Samuels, Lieckfeldt & Nirenberg and Trichoderma virens Pers. ex Fries isolated from the gut or cuticle of C. formosanus elicited significant termite aggregation in 2‐choice tests. We then screened 9 Trichoderma metabolites (3‐acetoxy‐2‐butanone, phenol, 3‐ethoxypropionic acid, ethyl 2,4‐dioxovalerate, diglycolic acid, d‐valine, styrene, 3‐aminopyridine, and hexyl acetoacetate) that triggered termite aggregation. Among them, phenol (1 000 μg/mL), 3‐ethoxypropionic acid (10 μg/mL), ethyl 2,4‐dioxovalerate (1 000 μg/mL), and diglycolic acid (1 000 μg/mL) showed the strongest activities, triggering termite aggregation throughout the 24‐h period. As T. asperellum and T. virens produce different metabolites that trigger aggregation behavior in termites, the mechanisms underlying the interaction between subterranean termites and Trichoderma fungi likely vary. Future studies are needed to test whether these chemicals can attract termites and increase bait consumption. [ABSTRACT FROM AUTHOR]

A hexameric quaternary ammonium salt surfactant Tz-6C12QC featuring a rigid triazine spacer and six ammonium groups was synthesized. The molecular structure and aggregation behavior of Tz-6C12QC were characterized by nuclear magnetic resonance spectroscopy, surface tension, conductivity, dynamic light scattering, and transmission electron microscopy, etc. Dissipative particle dynamics (DPD) simulation was employed to investigate the self-assembly behavior of Tz-6C12QC at different concentrations. The rheological behavior of the polyacrylamide/Tz-6C12QC system was characterized by shear rheology. The results indicated that Tz-6C12QC exhibited superior surface activity and lower surface tension compared to conventional surfactants. Rheology analysis revealed that Tz-6C12QC had a significant viscosity reduction effect on polyacrylamide. DLS and TEM indicated that, as the concentration of Tz-6C12QC increased, monomer associations, spherical aggregations, vesicles, tubular micelles, and bilayer vesicles were sequentially formed in the solution. This study presents a synthetic approach for polysurfactants with a rigid spacer and sheds light on the self-assembly process of micelles. [ABSTRACT FROM AUTHOR]

Colloidal particles, heterogeneous mixture with various organic components and continuous molecular weight (MW) distribution, is omnipresent in lake sediments and substantially influence the retention, transportation, and fate of contaminants in lake ecosystem. We sampled and extracted sedimentary colloids from different ecology regions in Taihu Lake, Jiangsu, East China, in June 2020, and they were further separated into four different particle size ranges by tangent ultrafiltration, and the properties of colloids were studied in various methods, including zeta potential analysis, transmission electron micrograph images (TEM), Fourier transformation infrared (FTIR), and 3D fluorescence. Results show that the surface of the colloids is covered with organic macromolecular substances, such as humus-like substances and protein-like substances. There were significant differences in molecular weight and fraction content of colloids in the sediments from macrophyte-dominant (MD) area and algae-dominant (AD) area in the lake. Colloids from MD area are mainly composed of humic acid, protein, and fulvic acid; the content of fulvic acid is lower than that of humic acid and protein. The humic acid exists mainly in small molecular weight (10–100 kDa), protein exists in mainly large molecular weight colloids (0.45–1 µm). Colloids from AD area are mainly composed of humic acid, and mainly distributed in the molecular weight (10 kDa–0.45 µm). The presence of humic acid inhibits effectively the agglomeration of the colloids. Especially, the stability of colloids is closely related to the molecular weight, with low molecular weight from MD area show higher stability. The existence of humic acid in colloids increases the electrostatic repulsion between colloidal particles, which can effectively inhibit the agglomeration of colloids, thus enhancing the stability of colloids. Furthermore, both monovalent and divalent electrolytes enhance colloidal aggregation, and the low-molecular-weight (LMW) colloid fraction exhibits higher stability efficiency than the high-molecular-weight (HMW) colloidal. [ABSTRACT FROM AUTHOR]

The occurrence of nanoplastics in agricultural land is a potential threat to human health and food security, yet the fate of nanoplastics is soil–root systems is poorly known. Here we investigated the aggregation behavior of polystyrene nanoplastics bearing different charges in cucumber root exudates and soil leachate, and in the presence of common environmental Ca2+ ions. Results show an increase in the aggregation size of positively charged amino-modified polystyrene nanoplastics, whereas negatively charged nanoplastics did not aggregate and showed no significant changes in particle size. This is possibly due to the adsorption of organic acids from soil leachates and root exudates onto the surfaces of nanoparticles. We observed that the critical condensation concentrations of Ca2+ for negatively charged nanoplastics increased by more than 1.4 times in root exudates and soil leachates compared with that in deionized water. Our findings suggest that root exudates and soil leachates can reduce the aggregation of negatively charged nanoplastics in Ca2+ solutions. [ABSTRACT FROM AUTHOR]

Wasps in the genus Sclerodermus are ectoparasitoids that typically attack the larvae of woodboring coleopterans. Interest in these species is increasing as they are used in programs to control longhorn beetle pests of economic importance in China and have invasive pest control potential in Europe. Wasps may be mass reared for field release, but using the target host species can be time consuming and physically demanding. There is thus a need for factitious hosts with lower production costs and that are easier to rear. The present research focuses on Sclerodermus brevicornis , which was found in Italy in association with the invasive longhorn beetle, Psacothea hilaris hilaris , and can be laboratory reared on this longhorn beetle and on a factitious lepidopteran host, Corcyra cephalonica. As it is known that the biology of natural enemies can be influenced by the host they emerge from and that the behavior of S. brevicornis is relatively complex due to its degree of sociality (multiple foundress females cooperate to paralyze the host and produce offspring communally), we explored whether, and how, performance and behavioral traits of adult females are influenced by the host species on which they were reared, both when no choice or a choice of current host species was offered. We evaluated the survival of foundresses and their movements between offered hosts and their tendency to form groups with other foundresses according to kinship and host characteristics. We also evaluated the production of offspring and the timing of their development. We found that S. brevicornis reared from C. cephalonica do have some disadvantages compared with those that have developed on P. h. hilaris but also that they recognize, prefer, and can reproduce on P. h. hilaris. We conclude that the use of the more convenient factitious host for mass-rearing is unlikely to greatly compromise the potential of S. brevicornis to suppress longhorn beetle pests in the field. [ABSTRACT FROM AUTHOR]

This work is aimed to study the interaction of an amphiphilic drug, promazine hydrochloride (PMZ) and two anionic surface active ionic liquids (SAILs), cholinium laurylsarcosinate [Cho][Sar] and cholinium deoxycholate [Cho][Doc] using conductivity, UV‐visible spectroscopy and fluorescence techniques. The results obtained by all three techniques indicated non‐ideal behavior and synergistic interactions between the PMZ drug and SAIL mixed systems. Further, the drug‐SAIL mixtures were used to stabilize silver nanoparticles (Ag NPs) in aqueous solution. The results of UV‐visible spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM) showed that PMZ and SAILs had strong electrostatic and hydrophobic interactions which played a significant role in the stabilization of Ag NPs. The morphological analysis of the Ag NPs showed the formation of various types of aggregates controlled by the internal packing of PMZ‐[Cho][Sar]/[Cho][Doc] mixed systems. These drug‐SAIL based NPs could be used in separation and synthesis applications in nanotechnology by altering the structure of drugs and SAILs. [ABSTRACT FROM AUTHOR]

The potential of potassium chloride (KCl) to be used as a substitute for sodium chloride (NaCl) was studied by monitoring the effects of salt treatment on thermal behavior, aggregation kinetics, rheological properties, and protein conformational changes. The results show that the addition of KCl can improve solubility, reduce turbidity and particle size, and positively influence rheological parameters such as apparent viscosity, consistency coefficient (K value), and fluidity index (n). These changes indicate delayed thermal denaturation. In addition, KCl decreased the content of β-sheet and random coil structures and increased the content of α-helix and β-turn structures. The optimal results were obtained with 2% KCl addition, leading to an increase in Tp up to 85.09 °C. The correlation results showed that Tp was positively correlated with solubility, α-helix and β-turn but negatively correlated with ΔH, turbidity, β-sheet and random coil. Overall, compared to NaCl, 2% KCl is more effective in delaying the thermal aggregation of LWE, and these findings lay a solid theoretical foundation for the study of sodium substitutes in heat-resistant liquid egg products.

Water filling occurs during the rapid salting of separated egg yolks. The purpose of this study was to investigate the changes in water migration, protein aggregation and structures of the separated egg yolks salted with 20% salt solution over 24 hours to understand the principles of this phenomenon. The results showed that water filling occurred within 12 h. The hardness of the salted egg yolk increased significantly within approximately 0−6 h and then decreased significantly. The springiness and cohesiveness of the egg yolk did not change significantly during salting. With the appearance of water filling, the T23, A23, soluble protein content, free sulfhydryl content, β-turns, α-helices and maximum fluorescence intensity (FImax) increased; the T22, A22, disulfide bonds, β-sheets, irregular curls, maximum emission wavelength (λmax) and average particle sizes decreased. This work showed that water filling enhanced the hydrogen bonding between proteins and water and inhibited protein aggregation.

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Heortia vitessoides Moore is a severe pest of Aquilaria sinensis (Lour.) Gilg, an important source of agarwood. In recent years, large amounts of chemical insecticides have been applied in A. sinensis plantations to deal with the outbreak of H. vitessoides, causing residue problems that reduce the quality and price of agarwood. Herein, we hypothesize that the widely applied biocontrol agent, Metarhizium anisopliae (Metschn.) Sorokin, can effectively kill the gregarious larvae of H. vitessoides through direct contact and horizontal transmission. RESULTS: At the concentration of 1 × 109 conidia/mL, the three M. anisopliae strains caused 100% mortality of H. vitessoides larvae. In addition, mixing donor larvae (previously treated with M. anisopliae conidia) with receptor larvae (which did not directly contact M. anisopliae conidia) caused significantly higher mortality of receptor larvae than the control receptors. This is due to the horizontal transmission of M. anisopliae conidia among live larvae, which was proven by pictures taken by scanning electron microscopy and induced activities of immunity‐related enzymes of donor and receptor larvae. Behavioral bioassays showed that M. anisopliae conidia had little effect on the aggregation tendency of H. vitessoides larvae but may trigger feeding‐avoidance behavior depending on M. anisopliae strains and concentrations. Interestingly, joint use of sublethal concentrations of M. anisopliae and chemical insecticides significantly increased larval mortality than each agent alone, indicating synergistic effects between M. anisopliae and insecticide against H. vitessoides. CONCLUSION: This study may provide a new strategy to suppress H. vitessoides population and reduce the use of chemical insecticides. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Stability and narrow size distribution are among the main requirements that apply to drug formulations based on polymeric nanoparticles. In this study, we obtained a series of particles based on biodegradable poly(D,L-lactide)-b-poly(ethylene glycol) (P(D,L)LAn-b-PEG113) copolymers with varied hydrophobic P(D,L)LA block length n from 50 to 1230 monomer units stabilized by poly(vinyl alcohol) (PVA) by a simple "oil-in-water" emulsion method. We found that nanoparticles of P(D,L)LAn-b-PEG113 copolymers with relatively short P(D,L)LA block (n ≤ 180) are prone to aggregate in water. P(D,L)LAn-b-PEG113 copolymers with n ≥ 680 can form spherical unimodal particles with values of hydrodynamic diameter less than 250 nm and polydispersity less than 0.2. The aggregation behavior of P(D,L)LAn-b-PEG113 particles was elucidated in terms of tethering density and conformation of PEG chains at the P(D,L)LA core. Docetaxel (DTX) loaded nanoparticles based on P(D,L)LA680-b-PEG113 and P(D,L)LA1230-b-PEG113 copolymers were formulated and studied. It was observed that DTX-loaded P(D,L)LAn-b-PEG113 (n = 680, 1230) particles are characterized by high thermodynamic and kinetic stability in aqueous medium. The cumulative release of DTX from the P(D,L)LAn-b-PEG113 (n = 680, 1230) particles is sustained. An increase in P(D,L)LA block length results in a decrease in DTX release rate. The in vitro antiproliferative activity and selectivity studies revealed that DTX-loaded P(D,L)LA1230-b-PEG113 nanoparticles demonstrate better anticancer performance than free DTX. Favorable freeze-drying conditions for DTX nanoformulation based on P(D,L)LA1230-b-PEG113 particles were also established. [ABSTRACT FROM AUTHOR]

A series of sulfonate silicone surfactants possessing different hydrophobic groups were synthesized. Their adsorption and thermodynamic parameters in aqueous solutions were investigated by surface tension measurements, conductivity, transmission electron microscopy (TEM) and dynamic light scattering (DLS). These sulfonate‐based anionic silicone surfactants exhibit significant surface activity and can reduce the surface tension of water to 19.6 mN m−1 at critical micelle concentration. The TEM and DLS results demonstrate that the three sulfonated silicone surfactants self‐assemble into homogeneous sized vesicle‐like aggregates in aqueous solution. Moreover, the size of the aggregates was determined to be in the range from 80 to 400 nm at 0.05 mol L−1. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: The spotted lanternfly, Lycorma delicatula White (Hemiptera: Fulgoridae), has recently emerged as a destructive invasive pest that is a great challenge to control. To develop and improve trapping, detection, and mitigation tools, it is crucial to understand what factors guide their behavior. Recent studies show that SLF aggregate, but the mechanisms driving aggregation behavior are poorly understood. This study evaluated the orientation behavior of SLF nymphs in the field when offered specific combinations of three factors: trees with different densities of SLF, tree size, and the presence of a semiochemical lure. When evaluated as a choice between two opposite characteristics while controlling for the two other factors, preferences were discernable, and all three factors were found to be attractive to SLF nymphs. Larger tree sizes and higher densities of SLF were highly attractive, and when forced to choose between them, only first instars revealed a preference for higher SLF density over larger-sized trees. When these two factors were controlled, methyl salicylate lures demonstrated four weeks of efficacy in the field but could not outcompete the draw of larger tree size or higher SLF density. A mark–release–recapture experiment was conducted to evaluate the orientation of spotted lanternfly (SLF) Lycorma delicatula White (Hemiptera: Fulgoridae) nymphs when released equidistant between two trees. The experiment was repeated weekly for eight weeks in a heavily infested area with mature tree-of-heaven Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae) planted in rows as ornamental street trees in Beijing, China. One tree in each pair received a methyl salicylate lure, and the lure was rotated between trees every week as it aged. Two additional independent variables for each tree were also analyzed: size and SLF population density. Marked–released SLF significantly chose trees with higher SLF population density over trees with lower density populations, and they also chose larger trees significantly more than smaller trees. Population density and tree size were better predictors of attraction than lures, but when those factors were controlled, SLF significantly chose trees with methyl salicylate lures over control trees for the first 4 weeks of lure life. Wild SLF distribution was assessed weekly, revealing strong aggregation in first and second instars that diminished with development to the third and fourth instars. Thus, nymphal SLF aggregate, and orientation is strongly guided by the presence of other SLF and tree size. [ABSTRACT FROM AUTHOR]

In this paper, sodium oleyl sulphate (SOS) was successfully synthesised by reacting octyl alcohol (OA) with gaseous sulphur trioxide (SO3) as a sulphating reagent in a falling film reactor. The structure was determined by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopy. The dynamic adsorption and aggregation behaviour of SOS was systematically investigated to reveal the relationship between the structure and properties of SOS. The physicochemical properties of SOS were determined by measuring the equilibrium surface tension, dynamic surface tension and dynamic contact angle, respectively. A laser particle size analyser and a transmission electron microscope (TEM) were used to analyse the aggregation behaviour of SOS. Compared to sodium dodecyl sulphate (SDS) and sodium n-octadecyl sulphate (C18H37OSO3Na), which have a similar structure to SOS, the increase in hydrophobic chain size and tighter molecular packing enabled by the polar head conformation caused a decrease in CMC and an increase in surface activity. The efficiency of the surface activity was controlled by a mixed diffusion kinetic adsorption mechanism. Moreover, SOS in aqueous solution showed efficient wettability on the surface of the low-energy paraffin film at concentration above the CMC. In addition, SOS molecules can spontaneously form spheroidal aggregates with increasing concentration, and the size of the aggregates increased with the concentration. [ABSTRACT FROM AUTHOR]

A hexameric quaternary ammonium salt surfactant Tz-6C12QC featuring a rigid triazine spacer and six ammonium groups was synthesized. The molecular structure and aggregation behavior of Tz-6C12QC were characterized by nuclear magnetic resonance spectroscopy, surface tension, conductivity, dynamic light scattering, and transmission electron microscopy, etc. Dissipative particle dynamics (DPD) simulation was employed to investigate the self-assembly behavior of Tz-6C12QC at different concentrations. The rheological behavior of the polyacrylamide/Tz-6C12QC system was characterized by shear rheology. The results indicated that Tz-6C12QC exhibited superior surface activity and lower surface tension compared to conventional surfactants. Rheology analysis revealed that Tz-6C12QC had a significant viscosity reduction effect on polyacrylamide. DLS and TEM indicated that, as the concentration of Tz-6C12QC increased, monomer associations, spherical aggregations, vesicles, tubular micelles, and bilayer vesicles were sequentially formed in the solution. This study presents a synthetic approach for polysurfactants with a rigid spacer and sheds light on the self-assembly process of micelles.

The severe aggregation property of the small molecule electron‐transporting layer (ETL) not only deteriorates the photovoltaic performance and operational reliability but also constrains its compatibility with large‐scale coating techniques. Herein, by applying N,N′‐Bis{3‐[3‐(Dimethylamino)propylamino]propyl}perylene‐3,4,9,10‐tetracarboxylic diimide (PDINN) (a well‐known ETL) as a demo, a solvent‐induced anti‐aggregation (SIAA) strategy is proposed to cope with these hurdles via the mixing of ethanol and trifluoroethanol solvents at an optimal volume ratio. In situ photoluminescence and dynamic light scattering synergistically reveals the suppressed aggregation behavior of the SIAA‐treated PDINN dispersion during the film‐forming process. Owing to this amendment, the film quality and electron‐transport capability of the PDINN layer are remarkably enhanced. In consequence, based on the PM6:L8‐BO system, a champion power conversion efficiency (PCE) of 19.0% together with an impressive fill factor of 80.6% is harvested. A 1 cm2 device with an excellent PCE of 16.6% is also fabricated using the doctor‐blading SIAA‐treated PDINN ink. More strikingly, this SIAA treatment impels better reliability under long‐term shelf‐lifetime and thermal stress periods. This work provides a promising and tractable approach to address the inherent self‐aggregation issue of electron‐transporting materials, which is beneficial for the development of efficient and stable organic optoelectronic devices. [ABSTRACT FROM AUTHOR]

The aggregation of locusts from solitary to gregarious phases is crucial for the formation of devastating locust plagues. Locust management requires research on the prevention of aggregation or alternative and greener solutions to replace insecticide use, and insect-derived microRNAs (miRNAs) show the potential for application in pest control. Here, we performed a genome-wide screen of the differential expression of miRNAs between solitary and gregarious locusts and showed that miR-8-5p controls the γ-aminobutyric acid (GABA)/glutamate functional balance by directly targeting glutamate decarboxylase (Gad). Blocking glutamate-GABA neurotransmission by miR-8-5p overexpression or Gad RNAi in solitary locusts decreased GABA production, resulting in locust aggregation behavior. Conversely, activating this pathway by miR-8-5p knockdown in gregarious locusts induced GABA production to eliminate aggregation behavior. Further results demonstrated that ionotropic glutamate/GABA receptors tuned glutamate/GABA to trigger/hamper the aggregation behavior of locusts. Finally, we successfully established a transgenic rice line expressing the miR-8-5p inhibitor by short tandem target mimic (STTM). When locusts fed on transgenic rice plants, Gad transcript levels in the brain increased greatly, and aggregation behavior was lost. This study provided insights into different regulatory pathways in the phase change of locusts and a potential control approach through behavioral regulation in insect pests. [ABSTRACT FROM AUTHOR]

A series of novel nonionic hydrocarbon/fluorocarbon hybrid surfactants (Hm-Fn, where m = 10, 12, 14, 16 and n = 4, 6, respectively) were successfully synthesized using polyethylene glycol, isophorone diisocyanate (IPDI), short chain fluoroalkyl alcohol and alkyl alcohol as starting materials. The preparation process involves the coupling reaction of isocyanate and hydroxyl groups. The surface activity and aggregation behavior of Hm-Fn in aqueous solution were studied by surface tension, steady-state fluorescence and dynamic light scattering (DLS) and transmission electron microscopy (TEM). The influence of the hydrophobic (hydrocarbon or fluorocarbon) chain length on surface activity of such hydrocarbon/fluorocarbon hybrid surfactants was systematically investigated. Micromorphology analysis revealed the presence of different sizes vesicles in H16-F6 and H16-F4 aqueous solution. In addition, the hydrophobic dye solubilization experiments exhibited that H16-F6 with a relatively longer fluorocarbon chain and hydrocarbon chain possessed more outstanding solubilization of model dye (Sudan I) compared with other Hm-Fn and conventional hydrocarbon surfactants. The molar solubilization power of H16-F6 could reach 0.0537. The above results demonstrated that these nonionic hydrocarbon/fluorocarbon hybrid surfactants might possess potential application prospects for hydrophobic dyes solubilization. [ABSTRACT FROM AUTHOR]

Two new anionic silicone surfactants were synthesized for the first time from dichloromethylvinylsilane or trichlorovinylsilane through hydrolysis‐condensation and then thiol‐ene reactions. Their structures were characterized by FT‐IR, 1H NMR and ESI‐MS. The surface tension (γ), critical aggregate concentration (CAC), surface pressure at CAC (ΠCAC ${\Pi _{C{\rm{A}}C} }$) and minimum surface area per surfactant molecule (Amin ${{A}_{\min } }$) were studied by surface tension and electrical conductivity, demonstrating their high surface activity at the gas/liquid interface. Transmission electron microscopy measurements showed that uniform spherical aggregates former in aqueous solution for both surfactants. Moreover, the size of the aggregates was determined to be in the range from 50 to 300 nm by dynamic light scattering. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) are attractive due to their advantages as solvents and electrolytes. Self-aggregation of surfactants would affect physico-chemical properties of DESs and thus electrochemical behavior of electroactive species in DESs. Aggregation behavior of sodium dioctyl sulfosuccinate (AOT) in choline chloride-ethylene glycol mixture containing 4 wt.% water (ethaline-4% H2O) was evaluated by surface-tension measurement. And surfactant effects on electrochemical behavior of copper ions in ethaline-4% H2O electrolyte were investigated by viscosity and ionic conductivity measurements, electrochemical experiments, and morphology analysis. The results show that critical micelle concentration value is 5.32 mM, and viscosity of ethaline-4% H2O increases upon increase of AOT concentration, while ionic conductivity decreases. Two redox couples relating to Cu(II)/Cu(I) and Cu(I)/Cu(0) from cyclic voltammograms were observed at both GCE and Pt electrodes. Using cyclic voltammograms of copper ions at Pt, diffusion coefficients and rate constants of Cu(II) were calculated and found to decrease when AOT concentration increases from 0 to 20 mM. Nucleation and growth processes are fitted well with instantaneous nucleation mode regardless of AOT concentrations from chronoamperometric data of Cu(I)/Cu(0) at GCE. Furthermore, scanning electronic microscopy analysis indicates that aggregation of surfactant AOT near critical micelle concentration plays important role in copper morphology control. [ABSTRACT FROM AUTHOR]

Abstract Amphoteric polymer can be used as retanning agent in leather manufacture. It is particularly useful in chrome-free tanning systems since it can regulate the charge properties of chrome-free leather and enhance the fixation of anionic post-tanning chemicals in leather. However, the aggregation and precipitation of amphoteric polymer retanning agents around the isoelectric point (pI) hinder their wide application. Herein, we synthesized five amphoteric acrylic polymers (AAPs) by free radical copolymerization with acrylic acid and five different cationic acrylic monomers. The effect of cationic monomer structure on the aggregation behavior of AAPs was investigated. The aggregation of AAPs in aqueous solution showed pH and concentration dependence. Light scattering analysis showed that Poly (AA-co-MAPTAC) and Poly (AA-co-DMAPMA) were in the shape of coiled linear flexible chains with small particle size (Rg 7.6 nm and 14.8 nm, respectively) near the pI. However, Poly (AA-co-DAC), Poly (AA-co-DMC) and Poly (AA-co-DMAEMA) were in the shape of hollow spheres and exhibited serious aggregation. Quantum chemical calculations suggested that the amide groups in the cationic monomers MAPTAC and DMAPMA enhanced the nucleophilicity of AAPs. Thus the corresponding AAPs could carry a large number of cationic charges to slow their aggregation when the pH just climbed over the pI. The results are expected to provide theoretical reference for the synthesis and widespread application of AAPs.

• The polyether-modified fluorosilicone significantly reduce the surface tension of water. • The polyether-modified fluorosilicone can wet on parafilm surfaces. • The polyether-modified fluorosilicone can self-assemble into vesicles in aqueous solution. Fluorosilicone surfactants integrate the advantages of fluorocarbon and organosilicone surfactants, resulting in desirable properties including enhanced surface activity and strong aggregation ability. In this study, a series of polyether-modified fluorosilicone (FSiPEs) was designed and synthesized. The structures of the parent hydrogen-terminated fluorosilicone oil (FPH-5) and the FSiPEs were characterized using Fourier transform infrared spectroscopy and 1H, 13C, 29Si, and 13C–1H HSQC nuclear magnetic resonance spectroscopy. The surface activity, aggregation properties, wettability, and foam properties of FSiPEs in aqueous solution were investigated using surface tension, dynamic light scattering (DLS), transmission electron microscopy (TEM), and dynamic contact angle measurements. The FSiPEs exhibited high surface activity in aqueous solution and good wettability on low-energy surfaces. In addition, the DLS and cryo-TEM results indicated that the FSiPEs can spontaneously form multilayer multicompartmental vesicles in aqueous solution. Consequently, these surfactants have potential applications in drug delivery and biofilm mimicry. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel high-performance Y-series polymer acceptor P4 was synthesized. • P4 displayed excellent miscibility with various donors (J71, PM6, PTB7-Th) • The all-polymer photodetectors based on J71:P4 achieved remarkable specific detectivity of 1.4 × 1014 Jones. • The J71:P4, PM6:P4, and PTB7-Th:P4 devices all showed the best photovoltaic performance compared with that of P1-P3. All-polymer optoelectronic devices have drawn extensive attention recently due to their outstanding thermal and mechanical stabilities. As one of the most promising acceptors, Y-series polymer have been widely utilized in all-polymer solar cells, but their applications in all-polymer photodetectors (all-PPDs) are rarely reported. Hence, developing a high-performance Y-series polymer acceptor with excellent universality for all-PPDs is urgently needed. Herein, we presented four polymer acceptors, P1-P4, by polymerizing Y-series small molecules with thiophene, bithiophene, difluoro-bithiophene, and thienothiophene π-bridges, respectively. Benefiting from improving the molecular symmetry without introducing disordered single bonds, P4 exhibited fine molecular stacking and orientation in the film state compared with P1-P3. Moreover, owing to the large torsion angle between thienothiophene and the end group of Y-unit, P4 displayed a more suitable aggregation behavior in the solution state, which gives P4 excellent miscibility with various donors. As a result, J71:P4 devices achieved remarkable specific detectivity of 1.4 × 1014 Jones at − 0.1 V, which is the highest detectivity reported for all-PPDs, as well as 1.3 × 1014 Jones for PM6:P4 devices and 8.0 × 1013 Jones for PTB7-Th:P4 devices. This work indicates that high-performance Y-series polymer acceptors with excellent universality can be realized by changing π-bridge units, which may accelerate the commercialization of all-PPDs. [ABSTRACT FROM AUTHOR]

• Synergistic effects can be formed between sodium erucate and short chain cationic surfactants. • The phase transition between wormlike micelle and vesicle can be triggered by temperature. • The components and concentrations of mixed system affects rheological properties of wormlike micelles. • NaOEr/HTAB wormlike micelles system has good carrying sand and gel breaking properties. Clean fracturing fluids are widely used in reservoir stimulation and increasing production due to their characteristics of simple preparation, no residue, easy flowback, and low damage. At present, clean fracturing fluids are mainly prepared by cationic surfactants as main agent and inorganic or organic salts as additives, which can lead to unavoidable losses of cationic surfactants due to their adsorption in the formation. Anionic-cationic surfactants composite system can not only compensate for the shortcomings of a single surfactant system, but also improve the reservoir adaptability of the surfactant system. In this paper, a clean fracturing fluid was prepared with long-chain anionic surfactant, Sodium erucate (NaOEr), as main agent and a series of cationic surfactants with different as additive. Then, the aggregation behavior of mixed system was determined by visual appearance, rheology experiments, differential scanning calorimetry and cryogenic transmission electron microscopy. The phase transition mechanism induced by temperature was proposed, and the performance of the mixed system as a fracturing fluid was evaluated. The results showed the mixed systems could self-assemble into wormlike micelles when the length of hydrophobic carbon chains of cationic surfactant was 6 and 8. Increasing the length of the hydrophobic carbon chain could enhance the electrostatic effect, leading to precipitation in the mixed system. When the ratio of cationic surfactant was between 0.5 and 0.6 and the concentration was between 68 and 175 mmol∙L-1, the mixed systems tended to form three-dimensional structures by entangling and stacking wormlike micelles, showing high viscoelasticity and viscosity. The aggregation structure of the mixed system transformed from vesicles to wormlike micelles at 46.8 °C, which is attributed to the transition of carbon chains of NaOEr from non-flexible to flexible. Finally, the mixed system as a fracturing fluid has good shear resistance and temperature resistance. The viscosity of NaOEr/HTAB can reach above 50 mPa⋅s after sheared for 60 min at the conditions of 170 s−1 and 80 °C. This study provides an anionic clean fracturing fluid and broaden the application of viscoelastic surfactants in oilfield development. [ABSTRACT FROM AUTHOR]

Functional third components targeted to improve a specific property of organic solar cells is an effective strategy. However, introducing a third component to simultaneously improve efficiency and stability and achieve good performance in thick-film devices has rarely been reported. Herein, low diffusion third components IDCN and ID2CN are reported to achieve a power conversion efficiency (PCE) of 18.08% and a high short-circuit current (J  SC ) of 27.82 mA cm -2 , one of the highest values based on PM6:Y6. They increase light harvesting in the range of 400-500 nm while enhancing energy transfer via Förster resonance energy transfer (FRET). A tightly ordered molecular arrangement is achieved by modulating the preaggregation and film formation kinetics of Y6, which enhance exciton dissociation and charge transport. Moreover, the low-diffusion third component can effectively restrict the diffusion of Y6 to improve the morphology stability, and the T 90 lifetime is increased from 689 to 1545 h. In 300 nm thick-film devices, PM6:ID2CN:Y6 achieves a PCE of 15.01%, much higher than PM6:Y6's 12.83%, demonstrating the great potential of ID2CN in thick-film devices., (© 2024 Wiley‐VCH GmbH.)

Stability and narrow size distribution are among the main requirements that apply to drug formulations based on polymeric nanoparticles. In this study, we obtained a series of particles based on biodegradable poly(D,L-lactide)-b-poly(ethylene glycol) (P(D,L)LAn-b-PEG113) copolymers with varied hydrophobic P(D,L)LA block length n from 50 to 1230 monomer units stabilized by poly(vinyl alcohol) (PVA) by a simple “oil-in-water” emulsion method. We found that nanoparticles of P(D,L)LAn-b-PEG113 copolymers with relatively short P(D,L)LA block (n ≤ 180) are prone to aggregate in water. P(D,L)LAn-b-PEG113 copolymers with n ≥ 680 can form spherical unimodal particles with values of hydrodynamic diameter less than 250 nm and polydispersity less than 0.2. The aggregation behavior of P(D,L)LAn-b-PEG113 particles was elucidated in terms of tethering density and conformation of PEG chains at the P(D,L)LA core. Docetaxel (DTX) loaded nanoparticles based on P(D,L)LA680-b-PEG113 and P(D,L)LA1230-b-PEG113 copolymers were formulated and studied. It was observed that DTX-loaded P(D,L)LAn-b-PEG113 (n = 680, 1230) particles are characterized by high thermodynamic and kinetic stability in aqueous medium. The cumulative release of DTX from the P(D,L)LAn-b-PEG113 (n = 680, 1230) particles is sustained. An increase in P(D,L)LA block length results in a decrease in DTX release rate. The in vitro antiproliferative activity and selectivity studies revealed that DTX-loaded P(D,L)LA1230-b-PEG113 nanoparticles demonstrate better anticancer performance than free DTX. Favorable freeze-drying conditions for DTX nanoformulation based on P(D,L)LA1230-b-PEG113 particles were also established.

A series of amphoteric surfactants containing carboxyl group and sodium sulfonate were synthesized from fatty amine (CnH2n + 1NH2, n = 12, 14, 16, 18), acrylic acid and sodium 3-chloro-2-hydroxypropyl sulfonate by two-step reaction. The surface activity and thermodynamic parameters were obtained by the measurement of surface tension and conductivity. The surface activity parameters showed that the critical micelle concentration (CMC) and adsorption area (ACMC) decreased with the increase of hydrophobic carbon chain length (n), while the balance surface tension (γCMC) first decreased and then increased with the increase of hydrophobic carbon chain length. The thermodynamic parameters show that the formation of micelles in aqueous solution is spontaneously exothermal and entropy-driven. The molar conductance reveals the existence of pre-micellization in the surfactant solutions for long hydrophobic carbon chain length. Water separation experiment showed that n = 18 had the strongest emulsifying ability. Foam experiments showed that the foaming property and foam stability of product n = 14 were the best. The series of amphoteric surfactants are low foaming surfactants. Synthesis and surface properties of amphoteric surfactants. [ABSTRACT FROM AUTHOR]

The present study aimed to systematically investigate the effects of different Abelmoschus manihot gum (AMG) concentrations (0–0.5%, w/w) on the formation of myofibrillar protein (MP) gels during heating process (30–80 °C) based on conformational alterations, protein aggregation behavior and molecular interactions. With the increase of temperature, the fluorescence intensity and α-helix content significantly decreased, revealing conformational transition of MP molecular. Dynamic rheological results indicated that MP had completely denatured and formed temporary gel at 50 °C, and completely formed irreversible cross-linked three-dimensional network structure at 80 °C. Moreover, the addition of AMG decreased the fluorescence intensity, as well as induced the transition of MP from α-helix to β-sheet during the whole heating process. Furthermore, AMG addition significantly decreased the turbidity and improved solubility of MP (P < 0.05), especially for at 0.3% AMG concentration, indicating that AMG accelerated the early unfolding and aggregation of MP during heating process. This was verified by the dynamic rheological results. Additionally, hydrophobic interactions and disulfide bonds were the main molecular forces to induce the formation of MP-AMG mixed gel. Therefore, our present results provided the new insights into the formation of MP-AMG mixed thermal-induced gel, and also contributed to the practical application of AMG in meat processing. [Display omitted] • Abelmoschus manihot gum (AMG) affects the myofibrillar protein (MP) gelation. • AMG promoted the unfolding of secondary structures and tertiary structures of MP. • Adding AMG was beneficial for the aggregation of the MP during heating process. • Aggregation of heads and cross-linking of tails of MP were enhanced by adding AMG. • The major interactions were hydrophobic interaction and disulfide bond over 50 °C. [ABSTRACT FROM AUTHOR]

The gastric aggregation characteristics of micellar casein (MC) are closely related to the surrounding digestive environment. Together with pepsin and gastric acid, the effect of serum Ca2+ in a digestive fluid is inevitable for the formation of those aggregates. In this study, MC powders with different levels of colloidal calcium phosphate (CCP) were controlled by quick-freezing process. The unique aggregation behaviors accompanied by the addition of exogenous Ca2+ during in vitro simulated digestion were investigated. The results showed that quick-freezing could significantly reduce the CCP level up to 50 % compared to controls. The dissociated micelle structure provided plenty of exposed binding sites, which was prone to recombine with serum Ca2+ in gastric fluids and thus formed the oversized nanoclusters and massive aggregates in stomach. Only about 40 % of the aggregates were dissolved and hydrolyzed after 120 min of gastric digestion. The results of wide-angle coupled small-angle X-ray scattering demonstrated that serum Ca2+ triggered aggregation behaviors largely depend on the pepsin and gastric acids. The para-κ-casein produced by pepsin could be quickly cross-linked by Ca2+-induced connections; while the exposed phosphoserine residues caused by gastric acids allowed more monomers to become nanoclusters by the effect of Ca2+ bridges. [Display omitted] • Quick-freezing induced significant exposure of Ca2+-binding sites in casein micelles. • The dissociated micelle was prone to recombine with serum Ca2+ in gastric fluids. • WAXS/SAXS was used to characterize the possible aggregation mechanism of MC. • Serum Ca2+ triggered aggregation behaviors largely depend on pepsin and gastric acids. [ABSTRACT FROM AUTHOR]

Abstract Polymer‐protein complexing systems have been extensively studied because of their wide application in biomedicine and industry. Here, we studied the aggregation behavior of the hydrophobically associating water‐soluble polymer poly(acrylic acid‐co‐octadecyl methacrylate) [P(AA‐co‐OMA)] prepared with nonionic surfactant as an emulsifier and bovine serum albumin (BSA) in aqueous solution. We identified the optimal composite conditions of P(AA‐co‐OMA) and BSA aqueous solution. We measured the zeta potential, dynamic light‐scattering particle size, and surface tension of P(AA‐co‐OMA) and BSA mixed aqueous solution. The results showed that the aggregation behavior between the polymer and BSA relied mainly on the hydrophobic interactions between the molecules. In addition, the best compounding condition was 8 wt.% of P(AA‐co‐OMA) content. The structure of hydrophobically associating polymer P(AA‐co‐OMA) and its aggregation with BSA were characterized by Fourier‐transform infrared spectroscopy. The infrared spectroscopy results identified the hydrogen bonding behavior of the amino and carboxyl groups between the polymer and BSA. This behavior was also confirmed using thermogravimetric analysis and differential scanning calorimetry. The thermal decomposition temperature and melting temperature of BSA changed before and after it was combined with the polymer. We measured the morphology of the polymer BSA aggregate with 8 % polymer content by transmission electron microscopy. The binding mechanism was investigated, as well.

• The content of −SO 3 − has significant effects on the aggregation behavior of WPET. • 14.1 % S-0 % PEG has the characteristics of rapid aggregation and rapid hydrolysis. • The conformation of 14.1 %S-0 %PEG was looser and NaOH was more likely to penetrate into the molecule. • The increase of NaOH concentration can accelerate the aggregation and hydrolysis of WPET. • This fundamental research is significant for predicting the stability and phase change of WPET in NaOH solution. Amphiphilic water-dispersed polyester (WPET) has broad application prospects in the textile field. However, due to the potential interactions between WPET molecules, the stability of WPET solution is susceptible to external factors. In NaOH solution, WPET was first aggregated and then hydrolyzed, and the molecular structure of WPET had a certain effect on the aggregation behavior and hydrolysis rate. In this paper, the aggregation patterns and hydrolysis rate of hydrophilic WPETs with different sulfonate contents in NaOH solution were studied. The results showed that the sulfonate content had a great effect on the aggregation behavior and hydrolytic process in NaOH solution in the PEG-free water-dispersed polyester. Compared with the water-dispersed polyester 9.5 % S-0 % PEG with low sulfonate content, the conformation of the water-dispersed polyester with high sulfonate content 14.1 % S-0 % PEG was looser (ρ = 1.65), and NaOH was more likely to penetrate into the molecule. Hence it is more sensitive to NaOH solution and has the characteristics of rapid aggregation and rapid hydrolysis. The increase of NaOH concentration can accelerate the aggregation and hydrolysis of WPET. Furthermore, the aggregation mechanism of WPET in NaOH solution was revealed. These findings are very useful for predicting the stability and phase transition of water-dispersed polyester in NaOH solution and are of great significance for promoting the application of water-dispersed polyester in the textile field. [ABSTRACT FROM AUTHOR]