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Urethane imide anhydride oligomers with terminal groups as anhydride groups were designed and synthesized using second‐order nonlinear optical chromophore molecule, bisphenol AF‐type diethylidene dianhydride, and toluene diisocyanate as monomers. Polyurethaneimide (PUI) second‐order nonlinear optical polymers with the structure of imide and amino ester chain segments were then synthesized by the polycondensation reaction between urethane imide anhydride oligomers and aromatic diamine monomers. The glass transition temperature (Tg) of PUI reached 186°C, and the 5% heat‐loss decomposition temperature was 320°C. The corona‐polarized PUI had an electro‐optic (EO) coefficient (γ33) of 82 pm/V tested by the reflection method. The loss of light transmission of the polymer waveguide prepared with PUI as electro‐optical material was 1.13 dB/cm at 1550 nm. Mach–Zehnder type polymer waveguide electro‐optical modulators have been prepared based on the properties of the electro‐optic material PUI. The fabricated polymer EO modulators had favorable electro‐optic modulation response performance for low‐frequency electrical signals. The good modulation characteristics of the manufactured electro‐optical modulators proved that the synthesized PUI was a waveguide polymer material with good comprehensive performance. Highlights: Electro‐optic fluorinated polyurethaneimide was synthesized.Polyurethaneimide as core material, polymer waveguide EO modulators were fabricated.The prepared modulators had good electro‐optic modulation performance. [ABSTRACT FROM AUTHOR]

Climate change poses several challenges in the wine industry, including increasing risks related to chemical food contaminants such as biogenic amines and ethyl carbamate (EC). In this work, we focused on urea removal in red wines by immobilized acid urease aiming at limiting EC formation during wine storage. By considering separable kinetics of catalyst deactivation and urea hydrolysis, it was possible to model the time course of urea removal in repeated uses in stirred batch reactors. Treatments based on immobilized urease of red wine enriched with 30 mg/L of urea allowed the reduction in the contaminant concentration to <5 mg/L. After 28.5 h of treatment, the observed urea level was reduced to about 0.5 mg/L, corresponding to a decrease in the potential ethyl carbamate (PEC) from 1662 μg/L to 93 μg/L, below the level of the non-enriched wine (187 μg/L). As a comparison, when treating the same wine with the free enzyme at maximum doses allowed by the EU law, urea and PEC levels decreased to only 12 mg/L and 415 μg/L respectively, after 600 h of treatment. These results show that, for red wines, urease immobilization is an effective strategy for urea removal and, thus, effective reduction in ethyl carbamate as a process contaminant. This study provides the scientific background for the future scaling-up of the process at an industrial level. [ABSTRACT FROM AUTHOR]

Photocuring 3D printing of materials exhibiting high fracture toughness and excellent mechanical properties (flexural strength/modulus) is challenging. Nowadays, most of the photocurable 3D printing resins are based on a mixture of multifunctional (meth)acrylates and provide therefore brittle materials. This article describes further developments of a toughening strategy based on the incorporation of block copolymers in low crosslink density methacrylate‐based materials. Six dimethacrylates bearing a bisphenol A core and urethane groups are successfully synthesized. Various spacers between the bisphenol A core and the methacrylate groups are selected. Each monomer is combined with (octahydro‐4,7‐methano‐1H‐indenyl)methyl acrylate as a monofunctional monomer and a poly(ε‐caprolactone)‐polydimethylsiloxane‐poly(ε‐caprolactone) triblock copolymer is added as toughener. It is shown that the addition of the triblock copolymer results for all mixtures in a strong increase of the fracture toughness. Moreover, the higher the amount of monofunctional monomer, the stronger the increase. The nature of the urethane dimethacrylate is found to have a significant influence on the fracture toughness, flexural strength, and flexural modulus of cured materials. Two of the synthesized dimethacrylates are identified as promising candidates for the development of fracture‐tough photocuring 3D printing materials. [ABSTRACT FROM AUTHOR]

Cellulose nanopaper is a material structure that possesses high mechanical performance and is widely regarded as a promising 2D reinforcement for polymer matrix composites. This work explores the use of low grammage bacterial cellulose (BC) nanopaper as reinforcement for poly(acrylated urethane) interlayer adhesive to increase the impact performance of multilayer acrylic composites. The BC nanopaper is impregnated with an acrylated urethane resin and laminated between acrylic sheets to create BC/acrylic composites consisting of one, three, and five layers of BC nanopaper‐reinforced poly(acrylated urethane) interlayer adhesive(s). Both the poly(acrylated urethane)‐filled BC nanopaper interlayer adhesive and the resulting laminated acrylic composites are optically transparent. The incorporation of BC nanopaper into the poly(acrylated urethane) interlayer adhesive improves the tensile modulus by eightfold and the single‐edge notched fracture toughness by 60% compared to neat poly(acrylated urethane). It is also found that using poly(acrylated urethane)‐filled BC nanopaper interlayer adhesive proves beneficial to the impact properties of the resulting laminated acrylic composites. In Charpy impact testing, the impact strength of the multilayer acrylic composites increases by up to 130% compared to the "gold‐standard" impact‐modified monolithic acrylic, with a BC loading of only 1.6 wt%. [ABSTRACT FROM AUTHOR]

Summary: Ethyl carbamate (EC) concentration is an important indicator of the safety of rice wine. In this study, the effects of replacing traditional starters with synthetic starters on the quality of rice wine were studied to provide a basis for the application of laboratory strains to explore the metabolic basis of EC formation in rice wine fermentation systems. The effects of synthetic starters on the physicochemical indices, free amino acids, flavour compounds, urea and EC of rice wine were studied. The results showed that the microorganism species and inoculation fermentation method strongly influenced the physicochemical and flavour properties of the rice wine, among which continuous co‐fermentation improved the mellowness and flavour of the rice wine. The concentrations of urea and EC in rice wine fermented with synthetic starters decreased significantly compared with those in the control group, in which the urea content decreased by up to 97.4% and the EC content decreased by up to 90.9%. In addition, the flavour compound data showed that the differences in the aromas of rice wine fermented with different starters were mainly due to the differences in the contents of alcohols and esters. These findings suggest that EC can be regulated by changes in starters and provide guidance for the optimal configuration of mixed fermentation systems. [ABSTRACT FROM AUTHOR]

Commercially available resin cements consist of various filler sizes, filler content and monomers, and it is unclear which of these factors have the greatest effect on the color stability of laminate veneers. To evaluate the color stability of lithium disilicate-reinforced laminate veneers inserted with three commercial resin cements with various filler sizes/contents and monomers upon accelerated aging. Veneers were fabricated and cemented on resin abutments using three commercially available resin cements comprised of two different monomers and varying filler sizes/contents: 1) triethylene glycol dimethacrylate, TEGDMA (RelyX™ Veneer = 0.6 µm/66 %, Calibra® Esthetic Light Cure =1.2 µm/65 %); and 2) urethane dimethacrylate, UDMA (Variolink Esthetic LC = 0.1 µm/38 %). A total of 60 specimens were fabricated (n = 20 for each cement). The relative number of particles (N) and relative surface area (A) were calculated for each filler size/content. Color coordinates (L*, a*, b*) were measured, and color change (ΔE 00) was calculated after cementation and following aging at 150, 300, 450, and 600 h using xenon light. Differences in color coordinates and color change were determined using repeated measures ANOVA followed by Tukey's post hoc test (α =.05). A post-hoc power analysis was performed to confirm reliability of the results. Based on a post-hoc power analysis of a repeated measures ANOVA with two between-factors and 1 within-factor, we had 89 % power to detect a difference of effect by cement type, 10 % power to detect a difference by shade, and 100 % power to detect a difference of effect by aging. The UDMA-based cement (0.1 µm/38 %) was least affected by aging, despite having the largest number of particles (N = 1010) and largest particle surface area (A = 7.02). The TEGDMA-based cements exhibited a significant color change, with 0.6 µm/66 % (A = 2.03, N = 8.12) producing a larger ΔE 00 than 1.2 µm/65 % (A = 1.00, N = 1.00). Among the commercial cements tested, UDMA-based resin (0.1 µm/38 %) provided better color stability than TEGDMA-based resin cements. The color change after aging was affected by the relative surface area and relative number of particles for the TEGDMA-based resin cement (0.6 µm/66 % and 1.2 µm/65 %), with a larger surface area and a higher relative number of particles, accelerated color change with aging. The present study demonstrates a novel approach to determine color stability for any resin cement with particulate filler. The dental practitioner should be selective in choosing a commercial light cure cementation product for laminate veneers, as UDMA containing resin cement is more resistant to color changes over time than TEGDMA, regardless of the filler size/content. [ABSTRACT FROM AUTHOR]

High-energy-density Li-CO2 batteries are promising candidates for large-capacity energy storage systems. However, the development of Li-CO2 batteries has been hindered by low cycle life and high overpotential. In this study, we propose a CO2-based thermoplastic polyurethane (CO2-based TPU) with CO2 adsorption properties and excellent self-healing performance to replace traditional polyvinylidene fluoride (PVDF) as the cathode binder. The CO2-based TPU enhances the interfacial concentration of CO2 at the cathode/electrolyte interfaces, effectively increasing the discharge voltage and lowering the charge voltage of Li-CO2 batteries. Moreover, the CO2 fixed by urethane groups (-NH-COO-) in the CO2-based TPU are difficult to shuttle to and corrode the Li anode, minimizing CO2 side reactions with lithium metal and improving the cycling performance of Li-CO2 batteries. In this work, Li-CO2 batteries with CO2-based TPU as the multifunctional binders exhibit stable cycling performance for 52 cycles at a current density of 0.2 A g−1, with a distinctly lower polarization voltage than PVDF bound Li-CO2 batteries. [ABSTRACT FROM AUTHOR]

Until recently, recycling thermoset polyurethanes (PUs) was limited to degrading methods. The development of covalent adaptable networks (CANs), to which PUs can be assigned, has opened novel possibilities for actual recycling. Most efforts in this area have been directed toward inventing new materials that can benefit from CAN theory; presently, little or nothing has been applied to industrially producible materials. In this study, both an industrially available polyol (Sovermol780®) and isocyanate (Tolonate X FLO 100®) with percentages of bioderived components were employed, resulting in a potentially scalable and industrially producible material. The resultant network could be reworked up to three times, maintaining the crosslinked structure without significantly changing the thermal properties. Improvements in mechanical parameters were observed when comparing the pristine material to the material exposed to three rework processes, with gains of roughly 50% in elongation at break and 20% in tensile strength despite a 25% decrease in Young's modulus and crosslink density. Thus, it was demonstrated that theory may be profitably applied even to materials that are not designed including additional bonds but instead rely just on the dynamic urethane bond that is naturally present in the network. [ABSTRACT FROM AUTHOR]

Aims: To explore the role of voltage‐gated calcium channels (VGCC) in 5‐HT2A/2C receptor agonist 2,5‐dimethoxy‐4‐iodophenyl‐2‐aminopropane hydrochloride's improvement of spinal cord injury (SCI) induced detrusor sphincter dyssynergia and the expressions of the 5‐hydroxy tryptamine (5‐HT) 2A receptors and VGCCs in lumbosacral cord after SCI. Methods: Female Sprague–Dawley rats were randomized into normal control group and SCI group (N = 15 each). Cystometrogram (CMG), simultaneous CMG, and external urethral sphincter electromyography (EUS‐EMG) were conducted in all groups under urethane anesthesia. Drugs were administered intrathecally during CMG and EUS‐EMG. Rats were euthanized and L6‐S1 spinal cord were acquired for immunofluorescence. Results: In SCI rats, intrathecal administration of 2,5‐dimethoxy‐4‐iodophenyl‐2‐aminopropane hydrochloride or L‐type VGCC blocker, nifedipine, could significantly increase voiding volume, voiding efficiency, and the number of high‐frequency oscillations. They could also prolong EUS bursting activity duration on EUS‐EMG. Moreover, the effect of 2,5‐dimethoxy‐4‐iodophenyl‐2‐aminopropane hydrochloride can be eliminated with the combined administration of L‐type VGCC agonist, (±)‐Bay K 8644. No significant differences were observed in CMG after intrathecal administration of T‐type VGCC blocker TTA‐P2. Additionally, immunofluorescence of the lumbosacral cord in control and SCI rats showed that the 5‐HT2A receptor and Cav1.2 immunolabeling‐positive neurons in the anterior horn of the lumbosacral cord were increased in SCI rats. Conclusions: Our study demonstrated that 5‐HT2A/2C agonist 2,5‐dimethoxy‐4‐iodophenyl‐2‐aminopropane hydrochloride may improve SCI‐induced DSD by inhibiting the L‐type voltage‐gated calcium channel in lumbosacral cord motoneurons. [ABSTRACT FROM AUTHOR]

Sustainable carbon dots comprising surficial oxime ester groups following homolytic bond cleavage exhibit potential as photoinitiators for traditional free radical photopolymerization. Carbon dots were made following a solvothermal procedure from sustainable furfural available from lignocellulose. Surficial aldehyde moieties reacted with hydroxylamine to the respective oxime while reaction with benzoyl chloride resulted in a biobased Type I photoinitiator comprising sustainable carbon dot (CD‐PI). Photoinitiating ability was compared with the traditional photoinitiator (PI) ethyl (2,4,6‐trimethyl benzoyl) phenyl phosphinate (TPO‐L) by real‐time FTIR with UV exposure at 365 nm. Photopolymer composition based on a mixture of urethane dimethacrylate (UDMA) and tripropylene glycol diacrylate (TPGDA) resulted in a similar final conversion of about 70 % using either CD‐PI or TPO‐L. Nevertheless, it appeared homogeneous in the case of compositions processed with CD‐PI, while those made with TPO‐L were heterogeneous as shown by two glass transition temperatures. Moreover, the migration rate of CD‐PI in the cured samples was lower in comparison with those samples using TPO‐L as PI. [ABSTRACT FROM AUTHOR]

The permeability for gases through polyurethane (PUR) aerogels prepared from unsorted PUR scraps by means of a recycling technique is measured with a dynamic pressure method. The permeabilities are in the range of 10−15 to 10−13 m2 and thus reflect the pore morphology observed with scanning electron microscopy. The permeability depends on the envelope density and microstructural features of the aerogels and decreases with increasing inner surface area. The comparison of the permeability with the Porod constant, which is obtained independently via small‐angle X‐ray scattering (SAXS), yields a high consistency with the expected theoretical relationship. However, a calculation of inner surface area based on permeability yields lower results than expected from data based on the established SAXS technique, revealing that the famous Carman–Kozeny law correlates only by trend, which is attributed to additional gas transport through the micro‐ and mesopores. A possible approach for the correlation of this behavior to the tortuosity is given. Several models accounting for the combined action of viscous flow, Knudsen diffusion, and molecular slip along pore walls are fitted to the experimental data, effectively qualifying the permeability measurement as time‐efficient and inexpensive technique for the characterization of structural features of aerogels. [ABSTRACT FROM AUTHOR]

Functionalized monomer with specific chain length leads to different behaviors of UV-curable polymers. Due to the high demand for high-performance bio-based coating, this research was conducted to understand the effect of fluoroacrylate monomer (FAM) additions on physicochemical properties of palm oil-based polyurethane (POPU) coating. POPU oligomer was synthesized through a series of steps which was acrylation and isocyanation to form acrylated epoxidized palm oil (AEPO) and POPU oligomer, respectively. The POPU oligomer was further added with trimethylolpropane triacrylate and 1,6 hexamethyl diacrylate monomers at 60/30/10 wt% compositions respectively to form 100 wt% resin and followed by the addition of FAM at different concentrations (2–12 parts per hundred resin, phr). The sample was cast on a silicone mold at 1 mm thickness and cured under UV radiation for 60 s. The chemical structure elucidation was successfully done by NMR on AEPO and POPU. In 1H NMR analysis, C = C group was detected at 2.0–3.0 ppm and OH peak at 3.687 ppm. For POPU, peak at 3.0 ppm in 1H NMR analysis suggested that NH functional has formed. In 13C NMR, the existence of urethane linkage at 172 ppm further confirmed the reaction. The SEM and XRD results revealed that the addition of FAM induced separation between molecules, which lowered the crosslinking density of POPU coating. The thermal properties of POPU improved glass transition temperature (Tg) of the coating by 2.64% at the addition of 2 phr FAM. The physical properties of POPU was also improved as excellent adhesion properties of FPOPU was shown at 2–6 phr FAM addition: for glass (4B), wood (3B), and steel (5B to 4B). The hardness also improved across all substrates, such as glass (2H to 6H), wood (3H to 4H), and steel (7H to 8H). On the other hand, the addition of higher FAM concentrations (8–12 phr) showed a reduction in thermal properties as the Tg decreased by 7.54%. Moreover, physical properties of FPOPU also deteriorate as high concentration of FAM added. The hardness decreased for glass (6H to 3H) and steel (6H to 5H). Adhesion also decreased for all the substrates tested, including glass (3B to 2B), wood (3B to 2B), and steel (5B to 3B). The optimum FAM addition contributing to high adhesion, hardness and thermal performance was observed at 4 phr, and the best surface application was steel surface. [ABSTRACT FROM AUTHOR]

SUMMARY: Barley produces several specialized metabolites, including five α‐, β‐, and γ‐hydroxynitrile glucosides (HNGs). In malting barley, presence of the α‐HNG epiheterodendrin gives rise to undesired formation of ethyl carbamate in the beverage production, especially after distilling. Metabolite‐GWAS identified QTLs and underlying gene candidates possibly involved in the control of the relative and absolute content of HNGs, including an undescribed MATE transporter. By screening 325 genetically diverse barley accessions, we discovered three H. vulgare ssp. spontaneum (wild barley) lines with drastic changes in the relative ratios of the five HNGs. Knock‐out (KO)‐lines, isolated from the barley FIND‐IT resource and each lacking one of the functional HNG biosynthetic genes (CYP79A12, CYP71C103, CYP71C113, CYP71U5, UGT85F22 and UGT85F23) showed unprecedented changes in HNG ratios enabling assignment of specific and mutually dependent catalytic functions to the biosynthetic enzymes involved. The highly similar relative ratios between the five HNGs found across wild and domesticated barley accessions indicate assembly of the HNG biosynthetic enzymes in a metabolon, the functional output of which was reconfigured in the absence of a single protein component. The absence or altered ratios of the five HNGs in the KO‐lines did not change susceptibility to the fungal phytopathogen Pyrenophora teres causing net blotch. The study provides a deeper understanding of the organization of HNG biosynthesis in barley and identifies a novel, single gene HNG‐0 line in an elite spring barley background for direct use in breeding of malting barley, eliminating HNGs as a source of ethyl carbamate formation in whisky production. [ABSTRACT FROM AUTHOR]

Lignin is the most abundant aromatic natural polymer, and receiving great attention in replacing various petroleum-based polymers. The aim of this study is to investigate the feasibility of technical lignin as a polyol for the synthesis of non-isocyanate polyurethane (NIPU) adhesives to substitute current polyurethane (PU) adhesives that have been synthesized with toxic isocyanate and polyols. Crude hardwood kraft lignin (C-HKL) was extracted from black liquor from a pulp mill followed by acetone fractionation to obtain acetone soluble-HKL (AS-HKL). Then, C-HKL, AS-HKL, and softwood sodium lignosulfonate (LS) were used for the synthesis of technical lignin-based NIPU adhesives through carbonation and polyamination and silane as a cross-linker. Their adhesion performance was determined for plywood. FTIR spectra showed the formation of urethane bonds and the reaction between lignin and silane. The NIPU adhesives prepared with C-HKL showed the highest adhesion strength among the three lignin-based NIPU adhesives. As the silane addition level increased, the adhesion strength of NIPU adhesives increased whereas formaldehyde emission decreased for all NIPU adhesives prepared. These results indicate that NIPU adhesives based on technical kraft lignin have a great potential as polyol for the synthesis of bio-based NIPU adhesives for wood bonding. [ABSTRACT FROM AUTHOR]

Currently, the preparation and application of bio-based thermoplastic polyurethane (TPU) are hot research topics in the field of polyurethane. In the present work, a series of polylactic acid (PLA)-based TPUs were synthesized using bio-based PLA and 4,4'-methylene diphenyl diisocyanate (MDI). The effects of three chain extenders, including 1,3-propanediol (PDO, PD), 1,4-butanediol (BDO, BD), and 1,6-hexanediol (HDO, HD), on the characteristics and properties of PLA-based TPUs were investigated. The successful synthesis of PLA-based TPUs was confirmed by the absence of isocyanate groups and the presence of characteristic peaks corresponding to urethane and other functional groups. The analyses revealed the potential for greater crystallization in the PLA-BD and PLA-HD series. Among the examined groups, the PLA-HD variant with a 55% hard segment content displayed the highest molecular weight and fracture stress, and an appropriate elongation value, indicating its suitability for specific applications. The study also investigated the stress relaxation rates and residual forces and found them to be within clinically acceptable ranges. These findings demonstrate the potential of these synthesized TPUs for orthodontic applications, with the ability to tailor mechanical properties by adjusting hard segment contents and modifying chain extenders. [ABSTRACT FROM AUTHOR]

Here, we describe an approach to synthesis of three-arm urethane derivatives bearing alkyloxybiphenyl units. Four new families of oligomers derived from 1,6-hexamethylene diisocyanate and their di- or trimers (uretdione, biuret or isocyanurate) and ω-hydroxyalkylated biphenyls were prepared. Their mesomorphic and optical properties were investigated by differential scanning calorimetry and POM. Mesomorphic properties were substantially impacted by the structure of the central core spacer (urethane, uretdione, biuret, or isocyanurate). The synthesized compounds shown the rich smectic polymorphism form from one to three different smectic phase. Stabilization of the LC state of synthesized oligomers was attributed to the H-bonding interactions confirmed by FT-IR spectra. The part of H-bonded urethane units is maximal for compounds with star-shaped central core. [ABSTRACT FROM AUTHOR]

Arginine deimination by Tetragenococcus halophilus , a halophilic lactic acid bacterium, is an undesirable reaction in soy sauce brewing because it is responsible for the production of ethyl carbamate, a potential carcinogen. Therefore, arginine deiminase system-deficient mutants have been generated and used as starter cultures. However, the pre-existing screening method for arginine deiminase system-deficient mutants was time consuming. To reduce the burden of this screening process, we established a method to isolate mutants incapable of arginine deimination using the arginine analog canavanine. Strains lacking arginine deiminase system were less sensitive to canavanine than wild type strain, which is likely because arginine deiminase consumes arginine in the cytoplasm and increases the relative concentration of canavanine in the cells and enhances its toxicity. This report provides an industrially useful method to efficiently obtain arginine deiminase system-deficient mutants. [ABSTRACT FROM AUTHOR]

Abstract Lung cancer (LC) ranks second most prevalent cancer in females after breast cancer and second in males after prostate cancer. Based on the GLOBOCAN 2020 report, India represented 5.9% of LC cases and 8.1% of deaths caused by the disease. Several clinical studies have shown that LC occurs because of biological and morphological abnormalities and the involvement of altered level of antioxidants, cytokines, and apoptotic markers. In the present study, we explored the antiproliferative activity of indeno[1,2-d]thiazolo[3,2-a]pyrimidine analogues against LC using in-vitro, in-silico, and in-vivo models. In-vitro screening against A549 cells revealed compounds 9B (8-methoxy-5-(3,4,5-trimethoxyphenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) and 12B (5-(4-chlorophenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) as potential pyrimidine analogues against LC. Compounds 9B and 12B were docked with different molecular targets IL-6, Cyt-C, Caspase9, and Caspase3 using AutoDock Vina 4.1 to evaluate the binding affinity. Subsequently, in-vivo studies were conducted in albino Wistar rats through ethyl-carbamate (EC)- induced LC. 9B and 12B imparted significant effects on physiological (weight variation), and biochemical (anti-oxidant [TBAR’s, SOD, ProC, and GSH), lipid (TC, TG, LDL, VLDL, and HDL)], and cytokine (IL-2, IL-6, IL-10, and IL-1β) markers in EC-induced LC in albino Wistar rats. Morphological examination (SEM and H&E) and western blotting (IL-6, STAT3, Cyt-C, BAX, Bcl-2, Caspase3, and caspase9) showed that compounds 9B and 12B had antiproliferative effects. Accordingly, from the in-vitro, in-silico, and in-vivo experimental findings, we concluded that 9B and 12B have significant antiproliferative potential and are potential candidates for further evaluation to meet the requirements of investigation of new drug application.

Lung cancer (LC) ranks second most prevalent cancer in females after breast cancer and second in males after prostate cancer. Based on the GLOBOCAN 2020 report, India represented 5.9% of LC cases and 8.1% of deaths caused by the disease. Several clinical studies have shown that LC occurs because of biological and morphological abnormalities and the involvement of altered level of antioxidants, cytokines, and apoptotic markers. In the present study, we explored the antiproliferative activity of indeno[1,2-d]thiazolo[3,2-a]pyrimidine analogues against LC using in-vitro, in-silico, and in-vivo models. In-vitro screening against A549 cells revealed compounds 9B (8-methoxy-5-(3,4,5-trimethoxyphenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) and 12B (5-(4-chlorophenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) as potential pyrimidine analogues against LC. Compounds 9B and 12B were docked with different molecular targets IL-6, Cyt-C, Caspase9, and Caspase3 using AutoDock Vina 4.1 to evaluate the binding affinity. Subsequently, in-vivo studies were conducted in albino Wistar rats through ethyl-carbamate (EC)- induced LC. 9B and 12B imparted significant effects on physiological (weight variation), and biochemical (anti-oxidant [TBAR's, SOD, ProC, and GSH), lipid (TC, TG, LDL, VLDL, and HDL)], and cytokine (IL-2, IL-6, IL-10, and IL-1β) markers in EC-induced LC in albino Wistar rats. Morphological examination (SEM and H&E) and western blotting (IL-6, STAT3, Cyt-C, BAX, Bcl-2, Caspase3, and caspase9) showed that compounds 9B and 12B had antiproliferative effects. Accordingly, from the in-vitro, in-silico, and in-vivo experimental findings, we concluded that 9B and 12B have significant antiproliferative potential and are potential candidates for further evaluation to meet the requirements of investigation of new drug application. [ABSTRACT FROM AUTHOR]

Baijiu is a renowned Chinese distilled liquor, notable for its distinctive flavor profile and intricate production process, which prominently involves fermentation and distillation. Ethyl carbamate (EC), a probable human carcinogen, can be potentially formed during these procedures, thus prompting significant health concerns. Consequently, the contamination of EC during Baijiu production has become an increasingly pressing issue. In this study, we developed a rapid and easily operable immunoassay for determining EC in the fermented materials used in Baijiu production. The development of a high-quality antibody specific to EC facilitated a streamlined analytical procedure and heightened method sensitivity. Furthermore, we systematically evaluated other essential parameters. Following optimization, the method achieved an IC50 value of 11.83 μg/kg, with negligible cross-reactivity against EC analogs. The recovery study demonstrated the method's good accuracy and precision, with mean recovery rates ranging from 86.0% to 105.5% and coefficients of variation all below 10%. To validate the feasibility of the technique, we collected and analyzed 39 samples simultaneously using both the proposed immunoassay and confirmatory gas chromatography–mass spectrometry (GC-MS). A robust correlation was observed between the results obtained from the two methods (R2 > 0.99). The detected EC levels ranged from 2.36 μg/kg to 7.08 μg/kg, indicating an increase during the fermentation process. [ABSTRACT FROM AUTHOR]

Effects of xanthene dyes and aerosil nanoparticles on the structure and dynamic characteristics of the cross-linked polyurethane were investigated by the IR-spectroscopy, dynamic-mechanical analysis, and electronic paramagnetic resonance methods. Dye molecule presence causes self-association of urethane groups within polymer rigid segments, weaker interactions between urethane groups and flexible oligoether parts and increased oligoether mobility. Increased mobility of flexible segments by xanthene dyes provides the necessary beam strength due to compensating the nanofiller network effect. The most efficient polyurethane material in the radiation resistance is expected to be a polymer composite with the highest permeability and the lowest modulus of elasticity. [ABSTRACT FROM AUTHOR]

Concise route for the synthesis of (-)-isoaltholactone and (±)-5-epi-OBn-Goniotriol were described. Key features for the (-)-isoaltholactone synthesis involved; a) diastereoselective and enantioselective aldol reaction between chiral pyrrolidine substituted γ-benzyloxy vinylogous urethane enolate and cinnamaldehyde afforded highly stereoselective syn δ-lactone, b) allylic 1,3-strain controlled epoxidation of styryl alkene following the stereospecific opening of the epoxide assisted by a proximal benzyloxy group completed the synthesis. Reaction of simple pyrrolidine substituted γ-benzyloxy vinylogous urethane enolate and cinnamaldehyde gave anti δ-lactone. Epoxidation and epoxide opening of the styryl alkene substrate of anti δ-lactone derivative was also investigated, which led to the synthesis of (±)-5-epi-OBn-Goniotriol. [ABSTRACT FROM AUTHOR]

In this paper, urethane-based acrylates (UA) were prepared via an environmentally friendly non-isocyanate route. Isophorone diamine (IPDA) reacted with ethylene carbonate (EC), producing carbamate containing amine and hydroxyl groups, which further reacted with neopentyl glycol diacrylate (NPGDA) by aza Michael addition, forming UA. The structures of the obtained intermediates and UA were characterized by 1H NMR and electrospray ionization high-resolution mass spectrometry (ESI-HRMS). The photopolymerization kinetics of UA were investigated by infrared spectroscopy. The composite with obtained UA can be UV cured quickly to form a transparent film with a tensile strength of 21 MPa and elongation at break of 16%. After UV curing, the mono-functional urethane acrylate was copolymerized into the cross-linked network in the form of side chains. The hydroxyl and carbamate bonds on the side chains have high mobility, which make them easy to form stronger dynamic hydrogen bonds during the tensile process, giving the material a higher tensile strength and elongation at break. Therefore, the hydrogen bonding model of a cross-linked network is proposed. The composite with UA can be 3D printed into models. [ABSTRACT FROM AUTHOR]

The receptor ability of diethyl N,N′‐(1,3‐phenylene)dicarbamate (1) to form host–guest complexes with theophylline (TEO) and caffeine (CAF) by mechanochemistry was evaluated. The formation of the 1–TEO complex (C12H16N2O4·C7H8N4O2) was preferred and involves the conformational change of one of the ethyl carbamate groups of 1 from the endo conformation to the exo conformation to allow the formation of intermolecular interactions. The formation of an N—H...O=C hydrogen bond between 1 and TEO triggers the conformational change of 1. CAF molecules are unable to form an N—H...O=C hydrogen bond with 1, making the conformational change and, therefore, the formation of the complex impossible. Conformational change and selective binding were monitored by IR spectroscopy, solid‐state 13C nuclear magnetic resonance and single‐crystal X‐ray diffraction. The 1–TEO complex was characterized by IR spectroscopy, solid‐state 13C nuclear magnetic resonance, powder X‐ray diffraction and single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

This study explores the synthesis of nanoparticles through the thermal decomposition of single‐source precursors, a method gaining popularity due to its low cost, minimal environmental toxicity, rapidity, scalability, and the ability to form nanoparticles with few defects. Zinc ethyl carbamate was synthesized and characterized using 1H NMR and infrared spectroscopy. Its purity was confirmed through microelemental analysis and melting point determination. The melting point of the complex was determined to be 165 °C. The thermogravimetric analyses indicated a one‐step decomposition of zinc ethyl carbamate with a decomposition onset of of 200 °C, yielding a stable ZnS residue. Further thermal decomposition led to the formation of wurtzite phase ZnS nanoparticles, as evidenced by XRD. SEM micrographs displayed mixed spherical, and cubic unevenly sized, polydispersed nanoparticles, while EDX revealed approximately a 1 : 1 Zn to S ratio. Estimated band gap from the Tauc's plot gave 3.93 eV and 3.42 eV for the nanoparticles synthesized at 300 and 400 °C respectively. The wide difference in the band gaps may be as a result of the larger particles observed at 400 °C and the deformations in the sample as observed in the SEM. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) plays an important role as a signalling molecule in the biological system. Organoselenium-coated or grafted biomaterials have the potential to achieve controlled NO release as they can catalyse decomposition of endogenous S-nitrosothiols to NO. However, such biomaterials are often challenged by the loss of the catalytic sites, which can affect the stability in tissue repair applications. In this work, we prepare a diselenide-containing poly(ester urethane)urea (SePEUU) polymer with Se–Se in the backbone, which is further electrospun into fibrous membranes by blending with poly(ester urethane)urea (PEUU) without diselenide bonds. The presence of catalytic sites in the main chain demonstrates stable and long-lasting NO catalytic activity, while the porous structure of the fibrous membranes ensures uniform distribution of the catalytic sites and better contact with the donor-containing solution. PEUU/SePEUU50 in 50/50 mass ratio has a physiologically adapted rate of NO release, with a sustained generation of NO after exposure to PBS at 37 °C for 30 d. PEUU/SePEUU50 has a low hemolysis and protein adsorption, with mechanical properties in the wet state matching those of natural vascular tissues. It can promote the adhesion and proliferation of human umbilical vein endothelial cells in vitro and control the proliferation of vascular smooth muscle cells in the presence of NO generation. This study exhibits the electrospun fibrous membranes have potential for utilizing as hemocompatible biomaterials for regeneration of blood-contacting tissues. Electrospun membranes of diselenide-containing poly(ester urethane)urea exhibit stable catalytic activity of NO generation, which promotes human umbilical vein endothelial cell proliferation and control the proliferation of vascular smooth muscle cells for potential applications as blood-contacting biomaterials. [ABSTRACT FROM AUTHOR]

The novel dioxane-polyether polyurethanes underwent a 12-month outdoor soil burial test to look into how they would degrade in a natural setting. The structure, thermal properties, surface features, and mechanical strength of the polyurethane films were compared. The initial chemical structure and subsequent chemical alterations were identified using FTIR spectroscopy. The polyurethane samples were less thermally stable throughout the duration of the soil burial test, according to TG/DTG curves. According to all findings, polyurethanes containing 1,3-dioxane-5,5-dimethanol exhibit excellent physical characteristics and mild degradation levels after being buried in soil for a year. These polyether urethanes can break down if the rigid domain structure is exposed to moisture and if microorganisms can spread into the polymer matrix. The physical properties, surface features, and degradation of polyether polyurethanes can be improved by varying the molar ratios of the hard segment components and the dioxane derivative structures. [ABSTRACT FROM AUTHOR]

WO3-based composite films synthesized using peroxo iso-polytungstic acid (W-IPA) and a transparent urethane resin exhibit reversible photochromic properties when irradiated with light. In this study, low-molecular-weight polyethylene glycols (PEGs, average molecular weights: 200-1000) were added to WO3-based composite films and their photochromic properties were evaluated. The WO3 particles in the composite films did not vary significantly in size, irrespective of the molecular weight of the added PEG. The addition of low-molecular-weight PEGs led to composite films with higher coloring and bleaching rates, with a remarkably high bleaching rate observed for the composite film containing PEG with a molecular weight of 400. The improved bleaching properties of the prepared films are mainly attributable to electron transfer associated with the presence of low-molecular-weight PEGs in the composite films. [ABSTRACT FROM AUTHOR]

We have innovatively formulated solid propellants by employing a catalyst‐free azide‐alkyne cycloaddition approach, steering away from the conventional urethane curing system reliant on moisture‐sensitive isocyanate compounds. These conventional systems exhibits poor compatibility with the eco‐friendly ionic oxidizers. Azide polymers, including polycaprolactone ether (PCE), polycaprolactone (PCL), and polyethylene glycol (PEG) were incorporated, with their terminal hydroxyl groups strategically modified with azides. Additionally, glycidyl azide polymer (GAP), characterized by an abundance of azides in its side chains, was introduced. For polybutadiene‐based solid propellants, a departure from the norm was pursued. We employed polybutadiene (PB) terminated with electron‐deficient alkynes(propiolate), synthesized through a urethane reaction involving an unsymmetric divalent chain‐linker containing both isocyanate and propiolate functionalities with hydroxyl‐terminated polybutadiene (HTPB). This approach diverged from the common practice of modifying other polymers with azides at the terminal. To ensure the attainment of optical mechanical properties in azide‐terminated polymer‐based solid propellants, trivalent propiolate curatives were judiciously combined with divalent propiolate curatives in an appropriate blend ratio. A meticulously synthesized series of polymeric bonding agents, designed to establish chemical links between solid oxidizers and polymer binder, revealed the idenfication of exceptional bonding agents. These agents played a pivotal role in delivering outstanding mechanical properties in solid propellants based on ammonium perchlorate (AP) and nitramine‐typed oxidizers. GAP‐based solid propellants were meticulously prepared, incorporating both urethane moieties at the terminal and triazole moieties at the side chains. Trivalent azide‐terminal curatives were introduced for crosslinking PB terminated with propiolates. Generally, triazole‐curing system resulted in solid propellants exhibiting notably higher burning rates compared to those crosslinked through urethanes. In summary, this research presents a sophisticated approach to the formulation of solid propellants, emphasizing a departure from conventional systems, strategic polymer modifications, and the meticulous synthesis of bonding agents to achieve superior mechanical properties and burning rates. [ABSTRACT FROM AUTHOR]

This article explores the use of dual bioorthogonal and orthogonal metabolic labeling techniques to study interactions in biological environments. The researchers developed modified 2'-desoxynucleosides to overcome the challenge of cross-reactivity and successfully linked genomic DNA in cells with two different fluorogenic markers. The study demonstrates the potential for advanced metabolic labeling strategies for nucleic acids, particularly in living cells. The authors conducted experiments to investigate the reactivity and selectivity of certain nucleosides in two different reactions, IEDDA and photoclick, for potential use in DNA labeling. While successful DNA marking was achieved using the IEDDA reaction, attempts to mark DNA using the photoclick reaction were unsuccessful. The authors also tested the nucleosides for metabolic labeling of cellular DNA, but no successful labeling was observed. Overall, this study provides a foundation for future research in metabolic labeling strategies for nucleic acids, including experiments in living cells. [Extracted from the article]

The goal of this work was to create shape memory polymer blends for the additive manufacturing technology of fused filament fabrication. An iterative approach was taken to develop a binary blend of polycaprolactone (PCL) and thermoplastic urethane (TPU). The composition of equal parts by mass PCL and TPU exhibited the best mechanical and shape memory properties. It was then decided to compound a ternary blend of PCL, TPU, and polylactic acid (PLA) where all components were of equal parts by mass. Constituents were chosen because they are all long chain polyesters with similar Hildebrand solubility parameters, because they are biocompatible, and because they all have some level of shape memory properties on their own. Dynamic mechanical analysis was performed to determine the recovery temperature for specimens that were deformed at room temperature. Scanning electron microscopy was used to perform fracture surface analysis of spent tensile test specimens. X-ray diffraction was used to explore aspects related to crystallinity of the blend materials. Transmission electron microscopy was used to characterize the mixing of the blend constituents where both the binary and ternary blends were found to be immiscible. The work presented here demonstrates materials selection based on structure, polymer family, and solubility parameter as a strategy for the development of multi-constituent polymer blends without the use of compatibilizers. [ABSTRACT FROM AUTHOR]

A general mechanism for catalytic urethane formation in the presence of acid catalysts, dimethyl hydrogen phosphate (DMHP), methanesulfonic acid (MSA), and trifluoromethanesulfonic acid (TFMSA), has been studied using theoretical methods. The reaction of phenyl isocyanate (PhNCO) and butan-1-ol (BuOH) has been selected to describe the energetic and structural features of the catalyst-free urethane formation. The catalytic activities of DMHP, MSA, and TFMSA have been compared by adding them to the PhNCO–BuOH model system. The thermodynamic properties of the reactions were computed by using the G3MP2BHandHLYP composite method. It was revealed that in the presence of trifluoromethanesulfonic acid, the activation energy was the lowest within the studied set of catalysts. The achieved results indicate that acids can be successfully employed in urethane synthesis and the mechanism was described. [ABSTRACT FROM AUTHOR]

Urethane acrylate (UA) was synthesized from various di-polyols, such as poly(tetrahydrofuran) (PTMG, Mn = 1000), poly(ethylene glycol) (PEG, Mn = 1000), and poly(propylene glycol) (PPG, Mn = 1000), for use as a polymer binder for paint. Polymethyl methacrylate (PMMA) and UA were blended to form an acrylic resin with high transmittance and stress-strain curve. When PMMA was blended with UA, a network structure was formed due to physical entanglement between the two polymers, increasing the mechanical properties. UA was synthesized by forming a prepolymer using di-polyol and hexamethylene diisocyanate, which were chain structure monomers, and capping them with 2-hydroxyethyl methacrylate to provide an acryl group. Fourier transform infrared spectroscopy was used to observe the changes in functional groups, and gel permeation chromatography was used to confirm that the three series showed similar molecular weight and PDI values. The yellowing phenomenon that appears mainly in the curing reaction of the polymer binder was solved, and the mechanical properties according to the effects of the polyol used in the main chain were compared. The content of the blended UA was quantified using ultravioletvisible spectroscopy at a wavelength of 370 nm based on 5, 10, 15, and 20 wt%, and the shear strength and tensile strength were evaluated using specimens in a suitable mode. The ratio for producing the polymer binder was optimized. The mechanical properties of the polymer binder with 5–10 wt% UA were improved in all series. [ABSTRACT FROM AUTHOR]

Although several force application concepts are known that can be used to deform shape memory polymers (SMPs) within the scope of programming, controlled deformation is challenging in the case of samples with a cylinder-like shape, which need to be homogeneously compressed starting from the lateral surface. To solve this problem, this contribution follows a material approach that takes advantage of four-dimensional (4D) printing. Fused filament fabrication (FFF) was used as an additive manufacturing (AM) technique to produce a thermoresponsive tool in a cylindrical shape from a polyether urethane (PEU) having a glass transition temperature (Tg) close to 55 °C, as determined by differential scanning calorimetry (DSC). Once it was 4D-printed, a sample of laser cut polyester urethane urea (PEUU) foam with a cylindrical wall was placed inside of it. Subsequent heating to 75 °C and keeping that temperature constant for 15 min resulted in the compression of the foam, because the internal stresses of the PEU were transferred to the PEUU, whose soft segments were completely molten at 65 °C as verified by DSC. Upon cooling to −15 °C and thus below the offset temperature of the soft segment crystallization transition of the PEUU, the foam was fixed in its new shape. After 900 days of storage at temperatures close to 23 °C, the foam recovered its original shape upon reheating to 75 °C. In another experiment, a 4D-printed cylinder was put into hibernation for 900 days before its thermoresponsiveness was investigated. In the future, 4D-printed tools may be produced in many geometries, which fit well to the shapes of the SMPs to be programmed. Beyond programming SMP foams, transferring the forces released by 4D-printed tools to other programmable materials can further expand technical possibilities. [ABSTRACT FROM AUTHOR]

This research aimed to address the issue of aflatoxin B1 (AFB1) contamination, which posed severe health and economic consequences. This study involved exploring unique species resources in the Qinghai-Tibet Plateau, screening strains capable of degrading AFB1. UPLC-Q-Orbitrap HRMS and NMR were employed to examine the degradation process and identify the structure of the degradation products. Results showed that Bacillus amyloliquefaciens YUAD7, isolated from yak dung in the Qinghai-Tibet Plateau, removed 91.7% of AFB1 from TSB-AFB1 medium with an AFB1 concentration of 10 µg/mL (72 h, 37°C, pH 6.8) and over 85% of AFB1 from real food samples at 10 µg/g (72 h, 37°C), exhibiting strong AFB1 degradation activity. Bacillus amyloliquefaciens YUAD7's extracellular secretions played a major role in AFB1 degradation mediated and could still degrade AFB1 by 43.16% after boiling for 20 min. Moreover, B. amyloliquefaciens YUAD7 demonstrated the capability to decompose AFB1 through processes such as hydrogenation, enzyme modification, and the elimination of the-CO group, resulting in the formation of smaller non-toxic molecules. Identified products include C12H14O4, C5H12N2O2, C10H14O2, C4H12N2O, with a structure consisting of dimethoxyphenyl and enoic acid, dimethyl-amino and ethyl carbamate, polyunsaturated fatty acid, and aminomethyl. The results indicated that B. amyloliquefaciens YUAD7 could be a potentially valuable strain for industrial-scale biodegradation of AFB1 and providing technical support and new perspectives for research on biodegradation products. [ABSTRACT FROM AUTHOR]

Animals must distinguish the sensory consequences of self-generated movements (reafference) from those of other-generated movements (exafference). Only self-generated movements entail the production of motor copies (i.e., corollary discharges), which are compared with reafference in the cerebellum to compute predictive or internal models of movement. Internal models emerge gradually over the first three postnatal weeks in rats through a process that is not yet fully understood. Previously, we demonstrated in postnatal day (P) 8 and P12 rats that precerebellar nuclei convey corollary discharge and reafference to the cerebellum during active (REM) sleep when pups produce limb twitches. Here, recording from a deep cerebellar nucleus (interpositus, IP) in P12 rats of both sexes, we compared reafferent and exafferent responses with twitches and limb stimulations, respectively. As expected, most IP units showed robust responses to twitches. However, in contrast with other sensory structures throughout the brain, relatively few IP units showed exafferent responses. Upon finding that exafferent responses occurred in pups under urethane anesthesia, we hypothesized that urethane inhibits cerebellar cortical cells, thereby disinhibiting exafferent responses in IP. In support of this hypothesis, ablating cortical tissue dorsal to IP mimicked the effects of urethane on exafference. Finally, the results suggest that twitch-related corollary discharge and reafference are conveyed simultaneously and in parallel to cerebellar cortex and IP. Based on these results, we propose that twitches provide opportunities for the nascent cerebellum to integrate somatotopically organized corollary discharge and reafference, thereby enabling the development of closed-loop circuits and, subsequently, internal models. [ABSTRACT FROM AUTHOR]

In this study, we investigate the reaction between water and the cis and trans limonene oxide mixture in the presence of ethyl carbamate ((R)-N-(α-methyl-benzyl)ethyl-carbamate), producing (1 R, 2 R, 4 R)-limonene-1,2-diol and trans limonene oxide. This study is carried out using the quantum mechanical density functional theory (DFT) method B3LYP-D3/6-31+G (d,p) to theoretically explain that 1,2-limonene diol is the hydrolysis product derived from cis limonene oxide, with trans limonene oxide not reacting (regioselectivity). For this reason, we exploit Fukui's frontier molecular orbital theory (FMO), local softness and local hardness ratios, transition states of the obtained products, the Fukui indices, and the thermodynamic quantities (enthalpy, entropy, free energy calculations). The theoretical results effectively elucidate the observed regioselectivity and corroborate the experimental findings. [ABSTRACT FROM AUTHOR]

'Top Shelf' (Reg. no. CV‐380, PI 704478), experimental designation DH162310, is a two‐row winter barley (Hordeum vulgare L.) released by Oregon Agricultural Experiment Station in 2023. It is a malting cultivar that is known to be a non‐producer of glycosidic nitrile (GN0). GN0 is the precursor to a regulated compound (ethyl carbamate) in distilled spirits and thus, the GN0 trait is becoming a requisite for malting cultivars geared toward distilling. While GN0 spring cultivars have been available for over 20 years, Top Shelf is the first winter GN0 cultivar to be released in North America, and only the second globally. In addition to its GN0 status it exceeds contemporary agronomic and malt quality expectations. Over 5 years of field trials in Oregon it performed equal to or better than the check entries. It shows high yields, plump grains, and test weights. It also has good resistance to scald (caused by Rhynchosporium commune) and preliminary data suggest resistance to barley stripe rust (Puccinia striiformis f. sp. hordei). Results were confirmed in field trials in southern Idaho, a major malting barley production region, and a target environment for this cultivar. Under standard malting protocols Top Shelf meets the guidelines for malt and all‐malt and/or grain distilling, and has high extract, enzymatic activity, and free amino nitrogen. When malted under optimized conditions, mimicking commercial distilling malt production, it produced even better results. As one of only a handful of GN0 cultivars available in the United States with potential for mainstream production, Top Shelf provides an important option for the distilling supply chain. Core Ideas: 'Top Shelf' is a non‐producer of glycosidic nitrile.'Top Shelf' is the first GN0 winter barley released in the United States.'Top Shelf' is well adapted to the Pacific Northwest (Idaho, Oregon, Washington).'Top Shelf' produces exceptional malt quality for distilling purposes. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the effect of varying printing layer thicknesses on the mechanical properties of a new 3D-printed polymer blend made of polylactic acid (PLA) and polycarbonate urethane (PCU). The specimen was created using the fused filament fabrication process. A universal testing machine and a Shore D durometer were used to perform the compression and hardness tests, respectively. Scanning electron microscopy (SEM) and an optical microscope were used to examine the surface morphology and failure mode of the tested specimens. The results showed that adding PCU to PLA decreased the compressive strength and Young's modulus of the 3D-printed polymer blend compared to 3D-printed PLA. The mechanical properties of 3D-printed specimens are also affected by the printing layer thickness. The hardness-to-elasticity ratio was also discovered to be a crucial characteristic when designing and selecting materials to enable proper load transfer. From the SEM image analysis, the cross-sectional surface area of the compression-molded specimen is smoother than that of the 3D-printed specimen, contributing to various types of failure modes for both specimens. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC) is a natural by-product in the production of fermented food and alcoholic beverages and is carcinogenic and genotoxic, posing a significant food safety concern. In this study, Clavispora lusitaniae Cl-p with a strong EC degradation ability was isolated from Daqu rich in microorganisms by using EC as the sole nitrogen source. When 2.5 g/L of EC was added to the fermentation medium, the strain decomposed 47.69% of ethyl carbamate after five days of fermentation. It was unexpectedly found that the strain had the ability to produce aroma and ester, and the esterification power reached 30.78 mg/(g·100 h). When the strain was added to rice wine fermentation, compared with the control group, the EC content decreased by 41.82%, and flavor substances such as ethyl acetate and β-phenylethanol were added. The EC degradation rate of the immobilized crude enzyme in the finished yellow rice wine reached 31.01%, and the flavor substances of yellow rice wine were not affected. The strain is expected to be used in the fermented food industry to reduce EC residue and improve the safety of fermented food. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, has released a list of papers published in 2024. These papers cover a wide range of topics in the field of chemistry, including photothermal properties of MXenes, pseudomorphic transformation of silica, and adsorption behavior of chloramphenicol. Other papers explore drug abuse detection in hair samples, photocatalytic performance, small-molecule tracer imaging, catalytic studies, colorimetric sensing, and more. These papers offer valuable research and insights in various areas of chemistry. [Extracted from the article]

Diethyl carbonate (DEC) was synthesized from ethanol and ethyl carbamate (EC) over Mg–Y composite oxides with excellent yield. Mg–Y composite oxide calcined at 450 °C demonstrated excellent catalytic activity and 70.3% yield was obtained. Note that the production capacity of catalysts (PCC) reached 5987 mgDEC gcat−1 h−1 under the optimized conditions, which was far higher than that reported in previous literature reports. Furthermore, other carbamates such as methyl carbamate (MC) and butyl carbamate (BC) could be also successfully converted into the corresponding dialkyl carbonates. The catalyst could be easily recovered four times under identical conditions. The origin of the catalytic performance was studied using various characterization techniques, and the TPD results showed that the MgY-450 catalyst exhibited more accessible moderate and strong basic sites, which was beneficial to expressing excellent catalytic performance. [ABSTRACT FROM AUTHOR]

Non-isocyanate polyurethane synthesis by non-Sn catalysis is an essential challenge toward green polyurethane synthesis. Bismuth compounds are attractive candidates due to their low cost, low toxicity, and availability to urethane chemistry. This work applied various Bi catalysts to the self-polycondensation of a bishydroxyurethane monomer and found BiCl3 to be an excellent catalyst through optimization. The catalytic activity and price of BiCl3 are comparable to those of Bu2SnO, while its toxicity is significantly low. BiCl3 is, therefore, a promising alternative to Sn-based catalysts in non-isocyanate polyurethane synthesis. [ABSTRACT FROM AUTHOR]

A sudden increase in polyurethane (PU) production necessitates viable recycling methods for the waste generated. PU is one of the most important plastic materials with a wide range of applications; however, the stability of the urethane linkage is a major issue in chemical recycling. In this work, termination reactions of a model urethane molecule, namely methyl N-phenyl carbamate (MPCate), are investigated using G3MP2B3 composite quantum chemical method. Our main goal was to gain insights into the energetic profile of urethane bond termination and find an applicable chemical recycling method. Hydrogenation, hydrolysis, methanolysis, peroxidation, glycolysis, ammonolysis, reduction with methylamine and termination by dimethyl phosphite were explored in both gas and condensed phases. Out of these chemicals, degradation by H2, H2O2 and CH3NH2 revealed promising results with lower activation barriers and exergonic pathways, especially in water solvation. Implementing these effective PU recycling methods can also have significant economic benefits since the obtained products from the reactions are industrially relevant substances. For example, aniline and dimethyl carbonate could be reusable in polymer technologies serving as potential methods for circular economy. As further potential transformations, several ionizations of MPCate were also examined including electron capture and detachment, protonation/deprotonation and reaction with OH−. Alkaline digestion against the model urethane MPCate was found to be promising due to the relatively low activation energy. In an ideal case, the transformation of the urethane bond could be an enzymatic process; therefore, potential enzymes, such as lipoxygenase, were also considered for the catalysis of peroxidation, and lipases for methanolysis. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC), a multisite carcinogenic compound, is naturally produced from urea and ethanol in alcoholic beverages. In order to reduce the content of EC in wine, the accumulation of arginine in Saccharomyces cerevisiae was regulated by genetic modifying genes involved in arginine transport and synthesis pathways to reduce the production of urea. Knockout of genes encoding arginine permease (Can1p) and amino acid permease (Gap1p) on the cell membrane as well as argininosuccinate synthase (Arg1) respectively resulted in a maximum reduction of 66.88% (9.40 µg/L) in EC, while overexpressing the gene encoding amino acid transporter (Vba2) reduced EC by 52.94% (24.13 µg/L). Simultaneously overexpressing Vba2 and deleting Arg1 showed the lowest EC production with a decrease of 68% (7.72 µg/L). The yield of total higher alcohols of the mutants all decreased compared with that of the original strain. Comprehensive consideration of flavor compound contents and sensory evaluation results indicated that mutant YG21 obtained by deleting two allele coding Gap1p performed best in must fermentation of Cabernet Sauvignon with the EC content low to 9.40 μg/L and the contents of total higher alcohols and esters of 245.61 mg/L and 41.71 mg/L respectively. This study has provided an effective strategy for reducing the EC in wine. • Modifying amino acid transporter and argininosuccinate synthase can reduce EC production. • EC content in the wine brewed by YVA11 is as low as 7.72 μg/L with a 68% decrease. • The higher alcohols produced by the recombinants reduced and the esters increased. • Recombinant strains YG11 and YG21 improve the flavor and sensory quality of wine. [ABSTRACT FROM AUTHOR]

A chitosan-based network was fabricated using hexamethylene diisocyanate as a crosslinking agent. The effect was investigated of incorporating star-shaped polycaprolactone (stPCL) into chitosan-based networks (CS/stPCL), where the stPCL content varied from 10 to 50 wt%. Quantitative analyses of the urethane/urea linkages and of the stPCL content in the networks were determined based on curve fitting and Soxhlet extraction, respectively. The optimum weight ratio was 80:20 for CS and stPCL (80CS20stPCL), with the highest urethane/urea linkages and stPCL content in the network (30.73%). The compressive testing and rheological analysis indicated that incorporating stPCL enhanced the compressive strength and rheological properties of the chitosan-based network. In addition, the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-2H-tetrazolium bromide assay of the CS/stPCL network had a cell viability percentage greater than 70%. The CS/stPCL network promoted the formation of an apatite layer on the surface, indicating that the CS/stPCL network could be a promising candidate for tissue engineering. [ABSTRACT FROM AUTHOR]

An NP‐GLIDE coating, featuring a liquid‐like polymer brush layer on its surface and nanopools of a grafted liquid ingredient for dewetting enablement within its matrix, is normally covalently cross‐linked (CX). This paper introduces a dually cross‐linked (DX) NP‐GLIDE coating, employing urethane bonds and H─bonds for crosslinking. Both the DX and CX coatings, utilizing poly(dimethyl siloxane) (PDMS) as the dewetting enabler, exhibit low ice adhesion strengths (τ). Post‐lubrication with silicone oil (SO), ice is readily shed under gravity from the coatings. The DX coating maintains low τ over numerous icing/de‐icing cycles, outlasting the CX coating. This durability is likely due to the lubricant‐loss‐responsive nature of the DX matrix. The matrix increases its H─bond cross‐links responding to lubricant loss and the cross‐linking density increase triggers additional lubricant release into the PDMS brush layer. This cyclic process persists over time. Under optimal conditions after 31 icing/de‐icing cycles, the lubricated DX coating demonstrates an impressively low τ of 1.8 ± 0.5 kPa. In contrast, the lubricated CX counterpart has a τ of 32 ± 11 kPa, while plain glass records a τ of 325 ± 14 kPa. This study underscores the significant potential of dual cross‐linking for enhancing ice‐shedding endurance of coatings. [ABSTRACT FROM AUTHOR]