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Commercial (protiated) samples of the "green" and biodegradable bioester 2-ethylhexyl laurate (2-EHL) were mixed with D-2-EHL synthesized by hydrothermal deuteration, with the mixtures demonstrating bulk structuring in small-angle neutron scattering measurements. Analysis in a polymer scattering framework yielded a radius of gyration (R (g)) of 6.5 angstrom and a Kuhn length (alternatively described as the persistence length or average segment length) of 11.2 angstrom. Samples of 2-EHL dispersed in acetonitrile formed self-assembled structures exceeding the molecular dimensions of the 2-EHL, with a mean aggregation number (N-agg) of 3.5 +/- 0.2 molecules across the tested concentrations. We therefore present structural evidence that this ester can function as a nonionic (co)-surfactant. The available surfactant-like conformations appear to enable performance beyond the low calculated hydrophilic-lipophilic balance value of 2.9. Overall, our data offer an explanation for 2-EHL's interfacial adsorption properties via self-assembly, resulting in strong emolliency and lubricity for this sustainable ester-based bio-oil., QC 20240223

Zirconocene triflate is a powerful moisture-tolerant catalyst for activation of C O bonds in carboxylic acids and alcohols in the absence of water scavenging techniques. Herein, an overview of the use of this robust metal complex for direct amidation, esterification, and etherification is presented, along with a discussion on mechanistic aspects of the transformations and the catalyst class., QC 20231108

TW transparent wood/polymer biocomposite laminates are of interest as multifunctional materials with good longitudinal modulus, tensile strength and optical transmittance. The effect of filling the pore space in wood with a polymer matrix on fracture toughness and crack growth is not well understood. Here, we carried out in-situ fracture tests on neat birch wood and laminates made of four layers of delignified birch veneers impregnated with poly(methyl methacrylate) (PMMA) and investigated crack growth in the tangential-radial (TR) fracture system. Fracture toughness KIc and JIc at crack initiation were estimated, including FEM analysis. SEM microscopy revealed that cracks primarily propagate along the ray cells, but cell wall peeling and separation between the PMMA and wood phases also take place. A combination of in-situ tests and strain field measured by digital image correlation (DIC) showed twice as long fracture process zone of TW laminates compared with neat birch.

Bioplastics that possess characteristics like durability and low cost are desired for versatile applications in industries such as automotive manufacturing, marine transport manufacturing, aerospace applications, and the building industry. The automotive industry is an example of an industry that is now shifting towards a more focused approach addressing the issue concerning sustainability and the development of sustainable material. To achieve a lightweight and sustainable construction, one of the methods used by the automotive original equipment manufacturers is by substituting conventional fossil-based, non-renewable composites, and metallic materials with a bio-based alternative. One of the drawbacks with biobased polymers can be the poor interfacial adhesion, leading to poor mechanical properties when compares to conventional material. The aim of this research is to investigate if a low-cost by-product could be used as a component in a composite matrix material in the automotive industry to reduce the final weight and increase the non-petrochemical material usage of composite material without compromising the thermal and mechanicals properties demanded. In this research, lignin was chemically altered by esterification the functional groups to increase the compatibility with polylactic acid. The esterification was performed with the use of acetic acid anhydride and pyridine. To evaluate and determine the esterification, Fourier transform Infrared Spectroscopy was used. By blending the modified lignin with polylactic acid the intention was to improve the thermomechanical properties and the interfacial linkage between the components. The effects of lignin acetylation on the tensile properties, impact strength, and thermal stability and moisture repellence behaviour were investigated. According to the experimental results the modification of lignin, increased the impact strength for all the blends containing acetylated lignin compares to pristine lignin. The larges

Background: Human chorionic gonadotropin (hCG) is produced by the placenta and plays an essential role in the maintenance of pregnancy. Endocrine disrupting chemicals (EDCs) have the potential to interfere with functions related to the production and secretion of hCG; however associations between exposure to EDCs and hCG concentrations in humans remain to be elucidated. Objectives: To investigate the association of urinary, serum and plasma concentrations of EDCs during pregnancy with serum hCG concentrations. Methods: We utilized data form the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy (SELMA) study. We investigated the association of 26 EDCs measured in early pregnancy urine or blood with serum hCG concentrations using multi-variable adjusted linear regression models per EDC and Weighted Quantile Sum (WQS) regression with repeated holdout validation for the EDCs mixture. Results: In 2,039 included women, higher exposure to bisphenol A was associated with lower hCG (beta [95% CI]: −0.06 [−0.11 to −0.002]) while higher triclosan exposure was associated with a higher hCG (0.02 [0.003 to 0.04]). Higher exposure to several phthalates, including mono-ethyl and mono-butyl phthalates (MEP and MBP) as well as metabolites of di-2-ethylhexyl phthalate (DEHP) was associated with a lower hCG (beta [95% CI] for sum of DEHP metabolites: −0.13 [−0.19 to −0.07]). Likewise, higher exposure to several polychlorinated biphenyls (PCBs) was associated with a lower hCG. In the WQS regression, each quartile increase in the EDCs mixture was associated with −0.27 lower hCG (95% CI: −0.34 to −0.19). Discussion: Higher exposure to several EDCs during pregnancy was associated with a lower hCG; and despite the small effect sizes, still indicating that the exposure may negatively affect production or secretion of hCG by the placenta. Our results provide the impetus for future experimental studies to investigate the placenta as a target organ for adverse effects of

Naturally occurring peptides with high membrane permeability often have ester bonds on their backbones. However, the impact of amide-to-ester substitutions on the membrane permeability of peptides has not been directly evaluated. Here we report the effect of amide-to-ester substitutions on the membrane permeability and conformational ensemble of cyclic peptides related to membrane permeation. Amide-to-ester substitutions are shown to improve the membrane permeability of dipeptides and a model cyclic hexapeptide. NMR-based conformational analysis and enhanced sampling molecular dynamics simulations suggest that the conformational transition of the cyclic hexapeptide upon membrane permeation is differently influenced by an amide-to-ester substitution and an amide N-methylation. The effect of amide-to-ester substitution on membrane permeability of other cyclic hexapeptides, cyclic octapeptides, and a cyclic nonapeptide is also investigated to examine the scope of the substitution. Appropriate utilization of amide-to-ester substitution based on our results will facilitate the development of membrane-permeable peptides.

IntroductionOverhead photoselective shade films installed in vineyards improve berry composition in hot grape-growing regions. The aim of the study was to evaluate the flavonoid and aroma profiles and composition of wines from Cabernet Sauvignon grapes (Vitis vinifera L.) treated with partial solar radiation exclusion.MethodsExperimental design consisted in a randomized experiment with four shade films (D1, D3, D4, D5) with differing solar radiation spectra transmittance and compared to an uncovered control (C0) performed over two seasons (2021 and 2022) in Oakville (CA, USA). Berries were collected by hand at harvest and individual vinifications for each treatment and season were conducted in triplicates. Then, wine chemical composition, flavonoid and aromatic profiles were analyzed.ResultsThe wines from D4 treatment had greater color intensity and total phenolic index due to co-pigmentation with anthocyanins. Shade film wines D5 and D1 from the 2020 vintage demonstrated increased total anthocyanins in the hotter of the two experimental years. In 2021, reduced cluster temperatures optimized total anthocyanins in D4 wines. Reduced cluster temperatures modulated anthocyanin acylation, methylation and hydroxylation in shade film wines. Volatile aroma composition was analyzed using gas chromatography mass spectroscopy (GCMS) and D4 wines exhibited a more fruity and pleasant aroma profile than C0 wines.DiscussionResults provided evidence that partial solar radiation exclusion in the vineyard using overhead shade films directly improved flavonoid and aroma profiles of resultant wines under hot vintage conditions, providing a tool for combatting air temperatures and warmer growing conditions associated with climate change.

Incorporation of a small content of undecenoic acid is proposed as an approach to introduce polar groups within the macromolecular architecture of high density polyethylene-based materials in order to promote an easier degradation after their useful service life. The influence of these hydrophilic groups during thermo and photo-oxidation processes has been then evaluated by several complementary techniques. In addition to different degradation rates, distinct ratios of oxidized species (lactones, ketones, carboxylic acids, esters and aldehydes) are found depending on: a) the initial material (neat high density polyethylene or ethylene-co-undecenoic acid copolymer); b) the type of oxidation (thermo or photoinduced); and c) the absence or presence of a specific prodegradant additive. An important increase of crystallinity has been observed in the final oxidized samples, indicating that the extent of degradation is rather significant., MICINN, Depto. de Química Orgánica, Sección Deptal. de Química Orgánica (Óptica y Optometría), Fac. de Ciencias Químicas, Fac. de Óptica y Optometría, TRUE, pub

Harnessing the potential of phase change materials can revolutionise thermal energy storage, addressing the discrepancy between energy generation and consumption. Phase change materials are renowned for their ability to absorb and release substantial heat during phase transformations and have proven invaluable in compact thermal energy storage technologies and thermal management applications. Present-day solutions mainly comprise of non-renewable phase change materials, where cyclability and sustainability concerns are increasingly being discussed. In pursuit of sustainable energy models, phase change material research has shifted towards biobased materials. This review explores the growing field of biobased phase change materials, aiming to identify prevailing trends, potential opportunities, and future applications. In addition, the persisting challenges of biobased phase change materials are discussed, where a critical dialogue on the current obstacles and research gaps is presented, offering a glimpse into the future of this rapidly evolving field. The authors furthermore present novel methods to enhance the integration of biobased phase change materials into thermal energy storage applications, ensuring their seamless adoption and maximum efficacy. With an analysis of 180 selected works, this review paints a vivid picture of the capabilities and promising prospects of biobased phase change materials, whilst highlighting the future research questions needing to be addressed., + ID der Publikation: hslu_99939 + Art des Beitrages: Wissenschaftliche Medien + Sprache: Englisch + Letzte Aktualisierung: 2024-01-15 10:44:02

Práce se zabývá možností využití methylesterů dvou typů rostlinných olejů (řepkový a lničkový) jako výchozích látek pro přípravu povrchově ochranných nátěrových hmot. V teoretické části je popsáno složení olejů, produkty, které se z olejů získávají (především epoxidy a jejich využití), základy povrchové ochrany a základy polymerace (zejména kationtové). V rámci experimentální práce byla provedena transesterifikace olejů, epoxidace vzniklých esterů a jejich aplikace v povrchové ochraně materiálů (kationtová polymerace pomocí UV záření) včetně měření různých vlastností. Výsledkem práce bylo zjištění, že samostatné epoxidy, připravené z přírodních olejů, jsou k povrchové ochraně materiálů nevhodné kvůli nízké reaktivitě epoxidových skupin na alifatickém řetězci. Nicméně směsi epoxidů s komerčně dostupnými pojivy jsou vhodné. Mechanické zkoušky pak dokázaly, že u směsí epoxidů s komerčními pojivy došlo ke zvýšení pružnosti a snížení tvrdosti filmů oproti čistým komerčním pojivům., The thesis is focusing on possibility of using methyl esters of two types of vegetable oils (rapeseed and camelina) as raw materials for the preparation of surface-protective coatings. Theoretical part describes composition of oils, products derived from oil (mainly epoxy and their use), foundations of surface protection and foundations of polymerization (mainly cationic). The experimental work included transesterification of oils, epoxidation of formed esters and their application in surface protection of materials (cationic polymerization by UV radiation) including measurement of various properties. It was found that pure epoxies, prepared from vegetable oils, were unsuitable for surface protection of materials due to low reactivity of epoxy groups on aliphatic chain. However, the mixtures of epoxides with commercially available binders are suitable for protection. The mechanical testing proved that mixtures of epoxides with commercial binders increased elasticity and reduced hardness in contrast to pure commercial binders., Fakulta chemicko-technologická, 1. Prezentace výsledků bakalářské práce a diskuze k posudku vedoucího bakalářské práce. Student zodpověděl všechny dotazy a připomínky k BP., Dokončená práce s úspěšnou obhajobou

Fermentation employing Saccharomyces cerevisiae has produced alcoholic beverages and bread for millennia. More recently, S. cerevisiae has been used to manufacture specific metabolites for the food, pharmaceutical, and cosmetic industries. Among the most important of these metabolites are compounds associated with desirable aromas and flavors, including higher alcohols and esters. Although the physiology of yeast has been well-studied, its metabolic modulation leading to aroma production in relevant industrial scenarios such as winemaking is still unclear. Here we ask what are the underlying metabolic mechanisms that explain the conserved and varying behavior of different yeasts regarding aroma formation under enological conditions? We employed dynamic flux balance analysis (dFBA) to answer this key question using the latest genome-scale metabolic model (GEM) of S. cerevisiae. The model revealed several conserved mechanisms among wine yeasts, for example, acetate ester formation is dependent on intracellular metabolic acetyl-CoA/CoA levels, and the formation of ethyl esters facilitates the removal of toxic fatty acids from cells using CoA. Species-specific mechanisms were also found, such as a preference for the shikimate pathway leading to more 2-phenylethanol production in the Opale strain as well as strain behavior varying notably during the carbohydrate accumulation phase and carbohydrate accumulation inducing redox restrictions during a later cell growth phase for strain Uvaferm. In conclusion, our new metabolic model of yeast under enological conditions revealed key metabolic mechanisms in wine yeasts, which will aid future research strategies to optimize their behavior in industrial settings.

Fermentation employing Saccharomyces cerevisiae has produced alcoholic beverages and bread for millennia. More recently, S. cerevisiae has been used to manufacture specific metabolites for the food, pharmaceutical, and cosmetic industries. Among the most important of these metabolites are compounds associated with desirable aromas and flavors, including higher alcohols and esters. Although the physiology of yeast has been well-studied, its metabolic modulation leading to aroma production in relevant industrial scenarios such as winemaking is still unclear. Here we ask what are the underlying metabolic mechanisms that explain the conserved and varying behavior of different yeasts regarding aroma formation under enological conditions? We employed dynamic flux balance analysis (dFBA) to answer this key question using the latest genome-scale metabolic model (GEM) of S. cerevisiae. The model revealed several conserved mechanisms among wine yeasts, for example, acetate ester formation is dependent on intracellular metabolic acetyl-CoA/CoA levels, and the formation of ethyl esters facilitates the removal of toxic fatty acids from cells using CoA. Species-specific mechanisms were also found, such as a preference for the shikimate pathway leading to more 2-phenylethanol production in the Opale strain as well as strain behavior varying notably during the carbohydrate accumulation phase and carbohydrate accumulation inducing redox restrictions during a later cell growth phase for strain Uvaferm. In conclusion, our new metabolic model of yeast under enological conditions revealed key metabolic mechanisms in wine yeasts, which will aid future research strategies to optimize their behavior in industrial settings

The high level of consumption of processed foods has an effect on human health. The consumption of doughnuts, pastries, fried chicken, French fried potatoes, snack chips, and imitation cheese is high among teenagers. These foods are generally rich in fats, although the focus has often been on the quantity rather than the quality of these fats. These products often contain saturated and trans fatty acids, which have adverse effects on triglycerides and cholesterol levels and raise lipoprotein(a) levels in plasma. These modifications are associated with the risk of developing certain health conditions, such as heart disease, stroke, type 2 diabetes, and obesity. It is important to note that not all fats have this negative effect on health. Dietary fats are an essential part that cannot be substituted for a healthy diet. A diet rich in healthy fats, such as monounsaturated and polyunsaturated fats, has an important benefit in human health. For this reason, it is crucial to read, identify, and interpret food labels in processed food to identify the presence of saturated or trans fats and choose healthier alternatives. Therefore, in this workshop, students in the first year of baccalaureate extracted oils and fats from a range of processed foods, quantifying and characterizing their nature by analyzing their fatty acid composition by gas chromatography. Subsequently, students compared their results according to the information given on the food package label and the literature. Finally, the students gave a talk on the work done in the laboratory and the knowledge gained from the students in lower grades, third and fourth years of high school, to raise awareness among these students.

Although the current literature describes significant advances in biocatalytic ester syntheses, few industrial plants worldwide are currently producing esters using biocatalysts. Green and sustainable esters can be obtained via a biocatalytic route, including some operational advantages over conventional syntheses. An analysis of the literature revealed that most articles neglect or describe the economic issues generically, without quantitative information. Scaling-up studies are also scarce in this field. The main disadvantage of biocatalysis using immobilized lipases—their cost—has not been studied at the same level of depth as other technical aspects. This gap in the literature is less intense in enzymatic biodiesel production studies and, despite the lack of a strict correlation, enzymatic biodiesel commercial plants are relatively more common. Preliminary techno-economic assessments are crucial to identify and circumvent the economic drawbacks of biocatalytic ester syntheses, opening the way to broader application of this technology in a large-scale context.

BACKGROUND: Attention-deficit/hyperactivity-disorder (ADHD) is a leading neurodevelopmental disorder in children worldwide; however, few modifiable risk factors have been identified. Organophosphate esters (OPEs) are ubiquitous chemical compounds that are increasingly prevalent as a replacement for other regulated chemicals. Current research has linked OPEs to neurodevelopmental deficits. The purpose of this study was to assess gestational OPE exposure on clinically-assessed ADHD in children at age 3 years. METHODS: In this nested case-control study within the Norwegian Mother, Father, and Child Cohort study, we evaluated the impact of OPE exposure at 17 weeks gestation on preschool-age ADHD. Between 2007 and 2011, 260 ADHD cases were identified using the Preschool Age Psychiatric Assessment and compared to a birth-year-stratified control group of 549 children. We categorized bis(2-butoxyethyl) phosphate (BBOEP) and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) as values < limit of detection (LOD) (BBOEP N = 386, BDCIPP N = 632), ≥LOD but < limit of quantification (LOQ) (BBOEP N = 413; BDCIPP N = 75), or above LOQ (BBOEP N = 70; BDCIPP N = 102). Diphenyl phosphate (DPhP) and di-n-butyl phosphate (DnBP) were categorized as quartiles and also modeled with a log10 linear term. We estimated multivariable adjusted odds ratios (ORs) using logistic regression and examined modification by sex using an augmented product term approach. RESULTS: Mothers in the 3rd DnBP quartile had 1.71 times the odds of having a child with ADHD compared to the 1st quartile (95%CI: 1.13, 2.58); a similar trend was observed for log10 DnBP and ADHD. Mothers with BDCIPP ≥ LOD but < LOQ had 1.39 times the odds of having a child with ADHD compared to those with BDCIPP < LOD (95%CI: 0.83, 2.31). Girls had lower odds of ADHD with increasing BBOEP exposure (log10 OR: 0.55 (95%CI: 0

Pd-catalyzed asymmetric allylic substitution (AAS) is a highly effective method for producing chiral molecules with alkene-substituted frameworks which can be further derivatized. However, its stereochemical outcome is affected by the steric requirements of the substrate and only a narrow set of nucleophiles yield excellent enantioselectivities. In this regard, phosphite-oxazolines have emerged as strong candidates to be privileged ligands for this process, providing results that surpass most of the previously published studies. They have provided high enantiocontrol when used in the Pd-AAS of several hindered and unhindered substrates, using a wide range of C-, O-, and N-nucleophiles. In this concept, we review and discuss the current progress made in the design of tailor-made phosphite-oxazoline ligand libraries for the Pd-AAS of a broad range of substrates and nucleophiles and its application in the construction of chiral complex molecules.

The storage of olives in large hoppers is a widespread practice in oil mills, but these large volumes and their unloading can cause a physical deterioration of the olives that will affect the quality of the oil obtained. This research deals with the effect of hopper charge on the formation of alkyl alcohols in olive fruits and its relationship with the sensory quality losses of ‘Arbequina’ virgin olive oil. The contents of ethanol, methanol, and acetaldehyde were measured in olive samples loaded and stored for a short time in a large hopper and analyzed at three different hopper-discharging times, which are related to three different positions inside the hopper. The corresponding oil from each sampling was obtained by using ABENCOR and was evaluated by a trained tasting panel. Results showed that the ethanol content in olives increased during their storage in the hopper, while methanol and acetaldehyde contents did not show significant differences. Regarding their position in the hopper, fruits located at the bottom or on the lateral sides showed a greater deterioration. The sensory analyses showed an inverse relationship between the positive attributes of olive oils and their content of alcohols.

AimsIn a retrospective analysis of dal-Outcomes, the effect of dalcetrapib on cardiovascular events was influenced by an adenylate cyclase type 9 (ADCY9) gene polymorphism. The dal-GenE study was conducted to test this pharmacogenetic hypothesis.Methods and resultsdal-GenE was a double-blind trial in patients with an acute coronary syndrome within 1-3 months and the AA genotype at variant rs1967309 in the ADCY9 gene. A total of 6147 patients were randomly assigned to receive dalcetrapib 600 mg or placebo daily. The primary endpoint was the time from randomization to first occurrence of cardiovascular death, resuscitated cardiac arrest, non-fatal myocardial infarction, or non-fatal stroke. After a median follow-up of 39.9 months, the primary endpoint occurred in 292 (9.5%) of 3071 patients in the dalcetrapib group and 327 (10.6%) of 3076 patients in the placebo group [hazard ratio 0.88; 95% confidence interval (CI) 0.75-1.03; P = 0.12]. The hazard ratios for the components of the primary endpoint were 0.79 (95% CI 0.65-0.96) for myocardial infarction, 0.92 (95% CI 0.64-1.33) for stroke, 1.21 (95% CI 0.91-1.60) for death from cardiovascular causes, and 2.33 (95% CI 0.60-9.02) for resuscitated cardiac arrest. In a pre-specified on-treatment sensitivity analysis, the primary endpoint event rate was 7.8% (236/3015) in the dalcetrapib group and 9.3% (282/3031) in the placebo group (hazard ratio 0.83; 95% CI 0.70-0.98).ConclusionDalcetrapib did not significantly reduce the risk of occurrence of the primary endpoint of ischaemic cardiovascular events at end of study. A new trial would be needed to test the pharmacogenetic hypothesis that dalcetrapib improves the prognosis of patients with the AA genotype.Clinical trial registrationTrial registration dal-GenE ClinicalTrials.gov Identifier: NCT02525939.

Growth suppression and defence signalling are simultaneous strategies that plants invoke to respond to abiotic stress. Here, we show that the drought stress response of poplar trees (Populus trichocarpa) is initiated by a suppression in cell wall derived methanol (MeOH) emissions and activation of acetic acid (AA) fermentation defences. Temperature sensitive emissions dominated by MeOH (AA/MeOH <30%) were observed from physiologically active leaves, branches, detached stems, leaf cell wall isolations and whole ecosystems. In contrast, drought treatment resulted in a suppression of MeOH emissions and strong enhancement in AA emissions together with volatiles acetaldehyde, ethanol, and acetone. These drought-induced changes coincided with a reduction in stomatal conductance, photosynthesis, transpiration, and leaf water potential. The strong enhancement in AA/MeOH emission ratios during drought (400%-3500%) was associated with an increase in acetate content of whole leaf cell walls, which became significantly 13 C2 -labelled following the delivery of 13 C2 -acetate via the transpiration stream. The results are consistent with both enzymatic and nonenzymatic MeOH and AA production at high temperature in hydrated tissues associated with accelerated primary cell wall growth processes, which are downregulated during drought. While the metabolic source(s) require further investigation, the observations are consistent with drought-induced activation of aerobic fermentation driving high rates of foliar AA emissions and enhancements in leaf cell wall O-acetylation. We suggest that atmospheric AA/MeOH emission ratios could be useful as a highly sensitive signal in studies investigating environmental and biological factors influencing growth-defence trade-offs in plants and ecosystems.

Polymethylmethacrylate is clinically used as a bone cement in various orthopedic and trauma surgeries. Post the surgery, such conventional acrylic bone cement has been reported to cause adjacent vertebral fractures; modifying it by adding linoleic acid in the formulation has shown potential in averting such fractures thanks to bone-compliant mechanical properties, besides providing convenient handling properties. Although the resulting properties are attractive, the understanding of how linoleic acid imparts such advantageous properties remain unclear. Linoleic acid is typically sterilized in an autoclave before being used in the bone cement formulation; however, there are apprehensions whether the sterilization causes degradation. In this research, sterilized and unsterilized linoleic acid were evaluated alone and with different components of bone cement, such as activator, initiator, monomer, and inhibitor, and the ensuing structural changes in linoleic acid were monitored through 1H NMR and UV–Vis. The results reveal that linoleic acid degrade due to sterilization. In addition, evidence for reactions of sterilized/unsterilized linoleic acid with activator and initiator have been collected. We hypothesize that these reactions can reduce the availability of the components for the in situ polymerization of methyl methacrylate monomer and cause the improvement in handling properties and decrease in mechanical properties., QC 20221214

The development of magnetic hybrid films containing diblock copolymers (DBCs) and magnetic nanoparticles (NPs) by printing is a highly promising method for scalable and low-cost fabrication. During printing, the drying and arrangement kinetics of the DBC and magnetic NPs play an important role in the film formation concerning morphology and magnetic properties. In this study, the morphology evolution of ultrahigh molecular weight DBC polystyrene-block-poly(methyl methacrylate) and magnetic iron platinum (FePt) NPs is investigated with grazing-incidence small-angle X-ray scattering (GISAXS) in situ during printing. For comparison, a pure DBC film is printed without FePt NPs under the same conditions. The GISAXS data suggest that the addition of NPs accelerates the solvent evaporation, leading to a faster film formation of the hybrid film compared to the pure film. As the solvent is almost evaporated, a metastable state is observed in both films. Compared with the pure film, such a metastable state continues longer during the printing process of the hybrid film because of the presence of FePt NPs, which inhibits the reorganization of the DBC chains. Moreover, investigations of the field-dependent magnetization and temperature-dependent susceptibility indicate that the printed hybrid film is superparamagnetic, which makes this film class promising for magnetic sensors., QC 20220511

Voltage-gated sodium channels (NaVs) are targets for a number of acute poisons. Many of these agents act as allosteric modulators of channel activity and serve as powerful chemical tools for understanding channel function. Herein, we detail studies with batrachotoxin (BTX), a potent steroidal amine, and three ester derivatives prepared through de novo synthesis against recombinant NaV subtypes (rNaV1.4 and hNaV1.5). Two of these compounds, BTX-B and BTX-cHx, are functionally equivalent to BTX, hyperpolarizing channel activation and blocking both fast and slow inactivation. BTX-yne-a C20-n-heptynoate ester-is a conspicuous outlier, eliminating fast but not slow inactivation. This property differentiates BTX-yne among other NaV modulators as a unique reagent that separates inactivation processes. These findings are supported by functional studies with bacterial NaVs (BacNaVs) that lack a fast inactivation gate. The availability of BTX-yne should advance future efforts aimed at understanding NaV gating mechanisms and designing allosteric regulators of NaV activity.

Organophosphate esters (OPEs) have been detected within car interior dust, suggesting that the indoor microenvironment of vehicles may represent a potential route of human exposure to OPEs. We recently showed that people with longer commutes are exposed to higher concentrations of tris(1,3-dichloro-2-isopropyl)phosphate (TDCIPP) - a widely used OPE - and other studies have suggested that dust removal may lead to lower exposure to chemicals. Therefore, the overall objective of this study was to determine if a decrease in interior car dust results in mitigation of personal OPE exposure. Participants (N = 49) were asked to wear silicone wristbands, and a subset of them wiped interior parts at the front of their vehicles prior to one study week (N = 25) or both study weeks (N = 11). There were no significant differences in total OPE concentrations (77.79-13,660 ng/g) nor individual OPE concentrations (0.04-4852.81 ng/g) across the different wiping groups nor in relation to participant residence ZIP codes and AC/Heater usage. These findings suggest that higher exposure to TDCIPP for participants with longer commutes may be independent of dust located on interior parts at the front of the vehicle. Therefore, our study demonstrates that there is a need for research on the potential contribution of other sources of TDCIPP exposure within car interiors.

Many disease-causing viruses target sialic acids on the surface of host cells. Some viruses bind preferentially to sialic acids with O-acetyl modification at the hydroxyl group of C7, C8, or C9 on the glycerol-like side chain. Studies of proteins binding to sialosides containing O-acetylated sialic acids are crucial in understanding the related diseases but experimentally difficult due to the lability of the ester group. We recently showed that O-acetyl migration among hydroxyl groups of C7, C8, and C9 in sialic acids occurs in all directions in a pH-dependent manner. In the current study, we elucidate a full mechanistic pathway for the migration of O-acetyl among C7, C8, and C9. We used an ab initio nanoreactor to explore potential reaction pathways and density functional theory, pKa calculations, and umbrella sampling to investigate elementary steps of interest. We found that when a base is present, migration is easy in any direction and involves three key steps: deprotonation of the hydroxyl group, cyclization between the two carbons, and the migration of the O-acetyl group. This dynamic equilibrium may play a defensive role against pathogens that evolve to gain entry to the cell by binding selectively to one acetylation state.

Fluorescent molecules have recently been used to observe and quantify biochemical processes. Within the last ten years, these molecules have been used to study serine hydrolases to learn more about how each one functions and what type of chemical groups they prefer. The data from the research on the BS2 serine hydrolase has revealed that there is a need to look further into the fluorogenic ester substrates that contain a cyclopropyl ring after data showed a strong preference to these substrates. This research project focused on the synthesis of fluorogenic cyclopropyl esters in preparation for biochemical assays. The synthesis was performed utilizing an original method developed by Dr. Luke Lavis. This original method needed to be altered for certain carboxylic acids, which revealed that extra steps to prevent hydrolysis of these unstable esters can lead to a larger yield, and success where past methods had failed. In total, thirteen syntheses were successfully completed, expanding the library of fluorescent molecules, and thus allowing further testing of the serine hydrolase preferences related to these substituted cyclopropyl ester derivatives. In the future, the modified methods used here could allow for further expansion of the library to include more unstable esters that have thus far been unattainable.

Supstituisani estri 1,4-dihidropiridina (1,4-DHP) nastaju u reakciji etil-acetoacetata i odgovarajućih supstituisanih aldehida u prisustvu amonijaka. Nastali estri sa primarnim aminima formiraju amide. Serija amida nastalih od navednih jedinjenja je sintetisana sa namerom da se ispitaju njihove karakteristike i antioksidativna aktivnost. U ovde prikazanom istraživanju za aminolizu upotrebljen je 2-aminotiazol. Antioksidativna aktivnost je ispitivana DPPH (2,2-difenil-1-pikrilhidrazil-radikal) i ABTS (2,2'-azino-bis(3-etilbenzotiazolin-6-sulfonska kiselina)) metodama, a pored toga određene su tačke topljenje, snimljeni IR spektri i izvršena je elementalna analiza., The substituted esters of 1,4-dihydropyirdines (1,4-DHP) are formed in the reaction of ethyl acetoacetate and corresponding substituted aldehydes in the presence of ammonia. Amides form from esters of substituted 1,4-DHP by aminolysis employing primary amines. A series of amides of the mentioned compounds was synthesized with the aim to analyze their chemical properties and antioxidative activity. The amine used in the present research was 2-aminothiazole. The antioxidative activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) methods; melting points and IR were measured and elemental analysis was performed.

The paper describes the properties of glycerol produced by transesterification, especially the ester content in the glycerol phase (ester losses) including the distribution of esters according to higher fatty acids. Glycerol, produced by transesterification of oil as a side product -the polar glycerol phase, is an important chemical raw material. The decreasing of ester losses is important because it (i) increases the ester yield and especially (ii) decreases the cost of glycerol purification. The transesterification of oils (rapeseed, olive, palm, sunflower and Camelina Sativa) with various distributions of fatty acids was carried out by methanol, ethanol and butanol including different transesterification stopping. The losses of ethyl and butyl esters are much higher than losses of methyl ester (approximately 2-3x). The dis-tribution of ethyl and butyl esters in the glycerol phase is the same as in the ester phase, whereas distribution of methyl ester is different and depends on the way of transesterification stopping. The reason is the different polarity of methyl esters, which depends on the type of fatty acid. The polarity increases with increasing of double bonds, i.e. the most soluble is methyl ester of linolenic acid in the glycerol phase. (c) 2021 Elsevier Ltd. All rights reserved., Práce popisuje vlastnosti glycerolu produkovaného transesterifikací, zejména z pohledu obsahu esterů v glycerolové fázi včetně distribuce esterů. Posuzovány byly ztráty esterů, jejich výtěžek a čistota glycerolu pro různé přírodní oleje zpracovávané metodou transesterifikace.

The chemistry of boron compounds has been profoundly investigated in the last decades, leading to ubiquity in many synthetic applications as well as biologically active molecules. Since the advent of photoredox catalysis, an upsurge in the discovery of suitable radical precursors has been witnessed, and boron is becoming a protagonist in this field. Despite many studies focused on trifluoroborates, the use of boronic acids and esters have received much less attention in this regard. Because of their high oxidation potential, the development of methods to enable their involvement in photocatalyzed reactions is only recent. Nonetheless, this review summarizes novel strategies developed to unlock their role as radical precursors in photochemical reactions and discloses the potential that boronic acids and esters own, when their intrinsic chemical properties are exploited.

Palladium catalyzes the cydclopropanation of 2-substituted 1,1-diborylalkenes with (trimethylsilyl)diazomethane. The relative stereoselectivity is controlled via a carbene insertion sequence generating an exclusive anti conformation between the R and SiMe3 substituents. Mixed 1,1-diborylalkenes also contributed to the formation of stereoselective B, B, Si-cyclopropanes. Orthogonal activation with (NaOBu)-Bu-t gives protodeborylation preferentially on the boron moiety syn to the aryl group. Further oxidation gives access to polyfunctional cycloopropyl alcohols with controlled enantioselectivity when chiral boryl motifs are involved.

In this article, we synthesized a novel dendritic 2-oxazoline, 2-(3,4,5-tris(4-dodecyloxybenzyloxy)phenyl)-4,5-dihydro-1,3-oxazole), and its amide precursor N-(2-hydroxyethyl)-3,4,5-tris(4-dodecyloxybenzyloxy)benzamide. Of the distinct synthetic routes explored, it was established that the direct amidation of esters with sodium methoxide followed by the dehydrative cyclisation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone as oxidizing agent and triphenylphosphine was the most efficient route to synthesize the dendritic 2-oxazoline. Besides, N-(2-hydroxyethyl)-3,4,5-tris(4-dodecyloxybenzyloxy)benzamide exhibited a monotropic columnar mesophase, whilst the dendritic 2-oxazoline does not exhibited a liquid crystalline mesophase. At the end, the first attempts to polymerize the 2-oxazoline monomer via cationic ring opening polymerization showed promising results. Therefore, the dendritic 2-oxazoline could be used as a mesogenic monomer in the synthesis of side-chain liquid-crystalline polyoxazolines that might self-assembly into columnar structures.© 2022. The Author(s).

Bioproduction of renewable chemicals is considered as an urgent solution for fossil energy crisis. However, despite tremendous efforts, it is still challenging to generate microbial strains that can produce target biochemical to high levels. Here, we report an example of biosynthesis of high-value and easy-recoverable derivatives built upon natural microbial pathways, leading to improvement in bioproduction efficiency. By leveraging pathways in solventogenic clostridia for co-producing acyl-CoAs, acids and alcohols as precursors, through rational screening for host strains and enzymes, systematic metabolic engineering-including elimination of putative prophages, we develop strains that can produce 20.3 g/L butyl acetate and 1.6 g/L butyl butyrate. Techno-economic analysis results suggest the economic competitiveness of our developed bioprocess. Our principles of selecting the most appropriate host for specific bioproduction and engineering microbial chassis to produce high-value and easy-separable end products may be applicable to other bioprocesses.

Chiral phase-transfer catalysis provides high level of enantiocontrol, however no experimental data showed the interaction of catalysts and substrates. 1 H NMR titration was carried out on Cinchona and Maruoka ammonium bromides vs. nitro, carbonyl, heterocycles, and N-F containing compounds. It was found that neutral organic species and quaternary ammonium salts interacted via an ensemble of catalyst + N-C-H and (sp2 )C-H, specific for each substrate studied. The correspondent BArF salts interacted with carbonyls via a diverse set of + N-C-H and (sp2 )C-H compared to bromides. This data suggests that BArF ammonium salts may display a different enantioselectivity profile. Although not providing quantitative data for the affinity constants, the data reported proofs that chiral ammonium salts coordinate with substrates, prior to transition state, through specific C-H positions in their structures, providing a new rational to rationalize the origin of enantioselectivity in their catalyses.

[ES] La cicloadición 1,3-dipolar entre alquinos y azidas ("Click Chemistry") catalizada por cobre (I), para formar 1,2,3-triazoles, es una de las reacciones más populares debido a su fiabilidad, especificidad y biocompatibilidad. Este tipo de mecanismos tienen el potencial de acortar los procedimientos y optimizarlos consiguiendo una economía atómica del 100%, además tienen la posibilidad de llevar a cabo la reacción en distintas condiciones y en un gran número de disolventes distintos, incluyendo el agua. Esta combinación de factores hace que las reacciones tipo "click" sean de gran utilidad para el diseño y la síntesis de una gran variedad de compuestos en condiciones óptimas de reacción. Un gran avance sería el descubrimiento de una reacción tipo "click" para amidas y esteres, que son compuestos químicos que se encuentran tanto en la naturaleza como en los laboratorios y de los cuales se conocen numerosos métodos sintéticos, sin embargo, estos no suelen ser sostenibles y generalmente requieren de reactivos peligrosos y condiciones violentas de reacción. Por estos motivos, en este trabajo se ha propuesto la síntesis de esteres y amidas a partir de la apertura de anillo de derivados de la ciclopropenona en presencia de aminas y alcoholes según los mecanismos de "Click Chemistry", utilizando distintas condiciones de reacción (temperatura, disolventes, catalizadores, etc.)., [EN] 1,3-dipolar cycloaddition between alkynes and azides catalyzed by copper (I) (click reaction), to form 1,2,3-triazoles, is one of the most popular reactions due to its reliability, specificity, and biocompatibility. Click reactions have the potential to perform shorter procedure and optimize them, achieving an atomic economy of 100%, and operate in different conditions and in many conventional solvents, including water. This combination of factors makes click reactions of great utility for the design and synthesis of a plethora compounds under optimal reaction conditions. A great advance would be the discovery of a click reaction for amides and esters synthesis, which are common chemicals in Nature, industry and academic laboratories. Indeed, a plethora of synthetic methods have been developed over the years, however, these methods are not sustainable and generally require harsh reagents or reaction conditions. For these reasons, in this work has been proposed the synthesis of esters and amides form the ring-opening of cyclopropenones derivatives in the presence of amines and alcohols according to the mechanisms of Click Chemistry.

Background: The extent of thyroid disruptive effects of phthalates during pregnancy remains unclear. Aim: To investigate the association of maternal urinary phthalates with markers of the thyroid system during early pregnancy. Methods: Urinary concentrations of phthalate metabolites and serum concentrations of thyroid stimulating hormone (TSH), free and total thyroxine (FT4 and TT4) and free and total triiodothyronine (FT3 and TT3) were measured in pregnant women in early pregnancy in the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy study (2007-ongoing), a population-based prospective cohort. Results: In the 1,996 included women, higher di-ethyl-hexyl phthalate (DEHP) metabolites were associated with a lower FT4 (β [SE] for the molar sum: −0.13 [0.06], P = 0.03) and a higher TSH/FT4 ratio (0.003 [0.001], P = 0.03). Higher concentrations of di-iso-nonyl phthalate (DINP) metabolites were associated with a lower TT4 (β [SE] for the molar sum: 0.93 [0.44], P = 0.03) as well as with lower TT4/FT4 and TT4/TT3 ratios. Higher metabolites of both dibutyl and butyl-benzyl phthalate (DBP and BBzP) were associated with lower T4/T3 ratio (free and total) and higher FT4/TT4 and FT3/TT3 ratios. A higher diisononyl cyclohexane dicarboxylate (DINCH) metabolite concentration was associated with a higher TT3. Conclusions: These results translate results from experimental studies suggesting that exposure to phthalates may interfere with the thyroid system during pregnancy. This is also true for compounds that have been introduced to replace known disruptive phthalates. Further experimental studies should take into account the human evidence to better investigate the potential underlying mechanisms of thyroid disruption by phthalates.

The host cell serine protease TMPRSS2 is an attractive therapeutic target for COVID-19 drug discovery. This protease activates the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and of other coronaviruses and is essential for viral spread in the lung. Utilizing rational structure-based drug design (SBDD) coupled to substrate specificity screening of TMPRSS2, we have discovered covalent small-molecule ketobenzothiazole (kbt) TMPRSS2 inhibitors which are structurally distinct from and have significantly improved activity over the existing known inhibitors Camostat and Nafamostat. Lead compound MM3122 (4) has an IC50 (half-maximal inhibitory concentration) of 340 pM against recombinant full-length TMPRSS2 protein, an EC50 (half-maximal effective concentration) of 430 pM in blocking host cell entry into Calu-3 human lung epithelial cells of a newly developed VSV-SARS-CoV-2 chimeric virus, and an EC50 of 74 nM in inhibiting cytopathic effects induced by SARS-CoV-2 virus in Calu-3 cells. Further, MM3122 blocks Middle East respiratory syndrome coronavirus (MERS-CoV) cell entry with an EC50 of 870 pM. MM3122 has excellent metabolic stability, safety, and pharmacokinetics in mice, with a half-life of 8.6 h in plasma and 7.5 h in lung tissue, making it suitable for in vivo efficacy evaluation and a promising drug candidate for COVID-19 treatment.

New thermoset composite material made from cardanol-based resin blended with microfibrillar cellulose was compared to petroleum-based vinyl ester and glass-fiber-reinforced unsaturated polyester in terms of mechanical, thermal, rheological and surface properties of produced polymers and composites. The bio-sourced material was less resistant than the commercial vinyl ester but comparable to the unsaturated polyester resin. Microfibrillar cellulose increased the tensile strength and modulus but increased the resin viscosity and decreased the mixture homogeneity. The bio-sourced and commercial resins displayed similar hydrophobic behavior, and cellulose slightly decreased composite hydrophobicity. The glass transition temperature of the bio-sourced material was comparable to that of the unsaturated polyester. Thermal decompositions of composites and thermoset polymers were also similar. Cellulose and cardanol thus may be adequate as sustainable components in the composite materials industry. © The Author(s) 2021.

This work aimed to study the biodegradation dynamics of plasticized cellulose acetate samples (etrols) with different content of plasticizers. Isophthalic acid dimethyl ester and orthophosphoric acid tributyl ester were used as plasticizers. The targets of the study also included assessing the effect of the plasticizers' content on the degradation rate. The biodegradability of plasticized cellulose acetate samples was assessed by measuring the weight loss after exposure to active soil. For the experiment, an active soil of the following composition was prepared: garden soil - 89 vol. %, distilled water - 10 vol. %, microbiological preparation "Tamir"- 1 vol. %. All etrols samples showed a tendency to decomposition in active soil. The rate of sample degradation varied significantly. The highest degradation rate in active soil was shown by a sample containing 16 wt. % tributyl phosphate and 22 wt. % dimethyl isophthalate, as good as ertols sample containing 8 wt. % tributyl phosphate and 14 wt. % dimethyl isophthalate. The expected decomposition time of these samples in the active soil for 90% is 599 and 732 days, respectively. Changing of dimethyl isophthalate content did not affect the degradation rate. Withal the content of tributyl phosphate in the etrols induced a significant effect on the samples' weight loss. The consequence of the plasticizers' content on the weight loss rate for 145 days of exposure in the active soil is described by the equation y=-4.76+1.25•Z 1+1.49•Z2-0.04•Z 12-0.086•Z22+0.000141 where Z1 is the content of dimethyl isophthalate, Z2 is the content of tributyl phosphate. © Published under licence by IOP Publishing Ltd.

Consumers look for unique wines, offering pleasant experiences. Wine producers need to open new markets and are targeting countries with fewer traditions in drinking red and complex wines, such as Poland, Russia and Germany. The use of less popular aging vessels (e.g., clay-tinajas) will help in creating unique wines. The aim of this study was to evaluate the effect of the aging vessel on the volatile and sensory profiles and consumer acceptance of red wine in Spain and Poland (model of potential new markets). Three wines were studied: (i) wine A, aged in a clay-tinaja with non-permeable coating); (ii) wine B, aged in clay-tinaja without coating; and (iii) wine C, aged in oak barrels (control). The key families in the volatile profiles were esters (wines B and C) and organic acids and terpenes (wine A). Wine A was described as sour and bitter, wine B had a distinctive mineral note, and wine C had a complex profile with typical wood notes. Finally, wines C and A were the preferred ones for Spanish and Polish consumers, respectively. Clay-tinaja wine A can be a good option to introduce clay-tinaja wines in Polish and similar markets because it is a unique product and fulfills the sensory demands/habits of Polish consumers.