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Ethylene/polar monomer coordination copolymerization offers an attractive way of making functionalized polyolefins. However, ethylene copolymerization with industrially relevant short chain length alkenoic acid remain a big challenge. Here we report the efficient direct copolymerization of ethylene with vinyl acetic acid by tetranuclear nickel complexes. The protic monomer can be extended to acrylic acid, allylacetic acid, ω-alkenoic acid, allyl alcohol, and homoallyl alcohol. Based on X-ray analysis of precatalysts, control experiments, solvent-assisted electrospray ionization-mass spectrometry detection of key catalytic intermediates, and density functional theory studies, we propose a possible mechanistic scenario that involves a distinctive vinyl acetic acid enchainment enabled by Ni···Ni synergistic effects. Inspired by the mechanistic insights, binuclear nickel catalysts are designed and proved much more efficient for the copolymerization of ethylene with vinyl acetic acid or acrylic acid, achieving the highest turnover frequencies so far for both ethylene and polar monomers simultaneously., The applications of polyolefins are limited by the nonpolar nature of the polymer. Here the authors show a method to copolymerize ethylene with the protic vinyl acetic acid via well defined multinuclear nickel catalysts.

BackgroundPast studies have found a strong relationship between alcohol drinking and human health.MethodsIn this study, we first tested the association of rs671 with alcohol use in 2349 participants in southeast China. We then evaluated the causal impact between alcohol use and cardiovascular traits through a Mendelian randomisation (MR) analysis.ResultsWe found strong evidence for the association of rs671 in the ALDH2 gene with alcohol drinking (p=6.08×10-47; ORadj G=4.50, 95% CI 3.67 to 5.52). We found that female G carriers of rs671 had a higher proportion of non-drinkers than male G carriers (88.01% vs 38.70%). In non-drinkers, the female G allele frequency was higher than the male G allele frequency (71.1% vs 55.2%). MR analysis suggested that alcohol use had a causal effect on blood pressure (increasing 9.46 mm Hg for systolic blood pressure (p=9.67×10-4) and 7.50 mm Hg for diastolic blood pressure (p=9.62×10-5)), and on hypertension in men (p=0.011; OR =1.19, 95% CI 1.04 to 1.36) and in pooled samples (p=0.013; OR =1.20, 95% CI 1.04 to 1.39), but not in women. We did not observe a causal effect of alcohol use on body mass index and lipid levels; further studies are needed to clarify the non-causal relationship.ConclusionsCompared to never-drinkers, current and previous alcohol use had a causal effect on blood pressure and hypertension in pooled samples and in men. These results reflect Chinese culture which does not encourage women to drink.

Multi-carbon alcohols such as ethanol are valued as fuels in view of their high energy density and ready transport. Unfortunately, the selectivity toward alcohols in CO2/CO electroreduction is diminished by ethylene production, especially when operating at high current densities (>100 mA cm−2). Here we report a metal doping approach to tune the adsorption of hydrogen at the copper surface and thereby promote alcohol production. Using density functional theory calculations, we screen a suite of transition metal dopants and find that incorporating Pd in Cu moderates hydrogen adsorption and assists the hydrogenation of C2 intermediates, providing a means to favour alcohol production and suppress ethylene. We synthesize a Pd-doped Cu catalyst that achieves a Faradaic efficiency of 40% toward alcohols and a partial current density of 277 mA cm−2 from CO electroreduction. The activity exceeds that of prior reports by a factor of 2., The electrocatalytic upgrading of CO to higher-value fuels provides a promising route to multi-carbon alcohol products. Here, the authors show that high alcohol selectivity and activity can be achieved by incorporating palladium in copper.

The core of the loline family of insecticidal alkaloids is the bicyclic pyrrolizidine unit with an additional strained ether bridge between carbons 2 and 7. Previously reported genetic and in vivo biochemical analyses showed that the presumptive iron- and 2-oxoglutarate-dependent (Fe/2OG) oxygenase, LolO, is required for installation of the ether bridge upon the pathway intermediate, 1-exo-acetamidopyrrolizidine (AcAP). Here we show that LolO is, in fact, solely responsible for this biosynthetic four-electron oxidation. In sequential 2OG- and O2-consuming steps, LolO removes hydrogens from C2 and C7 of AcAP to form both carbon–oxygen bonds in N-acetylnorloline (NANL), the precursor to all other lolines. When supplied with substoichiometric 2OG, LolO only hydroxylates AcAP. At higher 2OG:AcAP ratios, the enzyme further processes the alcohol to the tricyclic NANL. Characterization of the alcohol intermediate by mass spectrometry and nuclear magnetic resonance spectroscopy shows that it is 2-endo-hydroxy-1-exo-acetamidopyrrolizidine (2-endo-OH-AcAP). Kinetic and spectroscopic analyses of reactions with site-specifically deuteriated AcAP substrates confirm that the C2–H bond is cleaved first and that the responsible intermediate is, as expected, an FeIV–oxo (ferryl) complex. Analyses of the loline products from cultures fed with stereospecifically deuteriated AcAP precursors, proline and aspartic acid, establish that LolO removes the endo hydrogens from C2 and C7 and forms both new C–O bonds with retention of configuration. These findings delineate the pathway to an important class of natural insecticides and lay the foundation for mechanistic dissection of the chemically challenging oxacyclization reaction.

By using terahertz time-domain spectroscopy (THz-TDS), the transmission spectral images of a series of aliphatic monohydric liquid alcohols were investigated in this work. The image gray value indicated the non-uniform distribution of the liquid. After noise reduction, the depth distribution was computed from the image content, which depended on the wettability of the container surface by the liquid. Then the volume of the liquid crept up to the container surface was compared quantitatively. Our result showed that the surface wettability of the PS container surface by the liquids increased with the alcohol alkyl chain increasing, which was verified by the contact angle of the liquid and the surface. The study indicated that the THz image might offer a potential technique for detecting the wettability of liquid directly without an additional contact angle experiment.

Peach fruit volatile acetate esters impact consumer sensory preference and contribute to defense against biotic stresses. Previous studies showed that alcohol acyltransferase (AAT) family PpAAT1 is correlated with volatile ester formation in peach fruits. However, fruits also contain carboxylesterase (CXE) enzymes that hydrolyze esters. The functions of this family with regard to volatile ester content has not been explored. Here, we observed that content of acetate ester was negatively correlated with expression of PpCXE1. Recombinant PpCXE1 protein exhibited hydrolytic activity toward acetate esters present in peach fruit. Kinetic analysis showed that PpCXE1 showed the highest catalytic activity toward E-2-hexenyl acetate. Subcellular localization demonstrated that PpCXE1 is present in the cytoplasm. Transient expression in peach fruit and stable overexpression in tomato fruit resulted in significant reduction of volatile esters in vivo. Taken together, the results indicate that PpCXE1 expression is associated with catabolism of volatile acetate esters in peach fruit.

Traditionally, hollow CdS spheres can be prepared via a template-free hydrothermal process that requires higher Cd2+-to-S2− molar ratios with lower yields. In this research, we report a facile and template-free alcohol thermal approach for the synthesis of high-surface area hollow CdS microspheres at a 1 : 1 Cd2+-to-S2− molar ratio. The effects of the precursor chemical concentrations, reaction temperature and reaction time indicate that the formation of CdS hollow nanospheres was due to the Ostwald ripening mechanism. The stoichiometric Cd2+-to-S2− ratio promotes higher production of hollow CdS particles. The activities of the prepared CdS samples are evaluated based on the visible light photocatalytic degradation of methylene blue (MB) solution. Results indicate that the MB photocatalytic degradation rate is linearly related to the surface area of CdS particles with the highest photocatalytic activity for the hollow CdS microsphere samples having the highest surface area.

Chronic heavy alcohol consumption is a risk factor for cortical bone fractures in males. The increase in fracture risk may be due, in part, to reduced bone quality. Intracortical (osteonal) bone remodeling is the principle mechanism for maintaining cortical bone quality. However, it is not clear how alcohol abuse impacts intracortical bone remodeling. This study investigated the effects of long-duration heavy alcohol consumption on intracortical bone remodeling in a non-human primate model. Following a 4-month induction period, male rhesus macaques (Macaca mulatta, n = 21) were allowed to voluntarily self-administer water or alcohol (4% ethanol w/v) for 22 h/d, 7 d/wk for 12 months. Control monkeys (n = 13) received water and an isocaloric maltose-dextrin solution. Tetracycline hydrochloride was administered orally 17 and 3 days prior to sacrifice for determination of active mineralization sites. Animals in the alcohol group consumed 2.7 ± 0.2 g alcohol/kg/d (mean ± SE) during the 12 months of self-administration, resulting in a mean daily blood alcohol concentration of 77 ± 9 mg/dl from samples taken at 7 h after the start of a daily session. However, blood alcohol concentration varied widely from day to day, with peak levels exceeding 250 mg/dl, modeling a binge-drinking pattern of alcohol consumption. The skeletal response to alcohol was determined by densitometry, microcomputed tomography and histomorphometry. Significant differences in tibial bone mineral content, bone mineral density, and cortical bone architecture (cross-sectional volume, cortical volume, marrow volume, cortical thickness, and polar moment of inertia) in the tibial diaphysis were not detected with treatment. However, cortical porosity was lower (1.8 ± 0.5 % versus 0.6 ± 0.1 %, p = 0.021) and labeled osteon density was lower (0.41 ± 0.2/mm2 versus 0.04 ± 0.01/mm2, p < 0.003) in alcohol-consuming monkeys compared to controls, indicating a reduced rate of intracortical bone remodeling. In concordance, plasma CTx was lower (2.5 ± 0.3 ng/ml versus 1.7 ± 0.1 ng/ml, p = 0.028) in the alcohol group. These results suggest that chronic heavy alcohol consumption may negatively impact bone health, in part, by suppressing intracortical bone remodeling.

Oyster extract is an effective bioactivity component. It has abundant nutritional value and antiviral, antitumor and immune defense functions. The role of oyster extract in treating liver injury has been paid more attention. We use Wistar rats to make alcoholic liver disease model through injecting alcohol into rats’ stomachs. These rats were randomly divided into five groups: model group, control group, low-dose, middle-dose and high-dose experimental group with a dose of 0.12 g kg−1, 0.40 g kg−1, and 1.20 g kg−1 alcoholic. After nine weeks, serum biomarkers (ALT, AST, TG and TCHO), malondialdehyde (MDA), glutathione (GSH), C3a, C5a, IL-17, TNF-α, anti-MAA-HAS IgG, CD3+, CD4+, CD8+, NK cell activation and zinc content were assessed. The results showed that the serum biomarkers(ALT, AST, TG and TCHO), MDA content, anti-MAA-HSA IgG, serum C3a, C5a IL-17 and TNF-α levels of oyster extract treatment groups were significantly decreased in comparison with model group. On the contrary, GSH showed adverse trend. Serum CD3+, CD4+ and NK cell activation were significantly increased in middle-dose group and high-dose group compared with model group, and there was decrease of CD8+ activity in high-dose group. Plasma Zn level was decreased in model group compared with that in control group. Meanwhile, Mean plasma Zn levels increased dramatically following the dose increase of a given oyster extract.

Aims Previous studies have shown inconsistent findings with regard to the association between amount of spending money and adolescent smoking. Drinking alcohol may be a mediator of the association between spending money and adolescent smoking. However, no studies have examined this potential role. The objective of this study was to investigate the association between amount of spending money and adolescent smoking and the potential mediation role of alcohol use in this association. Design The 2003 Ontario Student Drug Use Survey of students in grades 7–12. Measurements Multivariable logistic, probit and linear regression models were used to investigate the association between amount of spending money and smoking, and the contribution of drinking alcoholic beverages to this relationship. Findings Spending money was associated positively with experimental smoking, current smoking and daily consumption of cigarettes (P

Alcohols were derivatised to their carbazole-9-N-acetic acid (CRA) esters with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC.HCl) as the dehydrating agent. Studies on derivatisation conditions indicated that the coupling reaction proceeded rapidly and smoothly in the presence of a base catalyst in acetonitrile to give the corresponding sensitively fluorescent derivatives. The retention behaviour of alcohol derivatives was investigated by varying mobile phase compositions (ACN-water and MeOH-water). The parameters from the equation log k'=A-BX were evaluated by retention data of derivatives using an isocratic elution with different mobile phases. The results indicated that the parameters derived allowed computation of retention factors in good agreement with experiments. At the same time, a general equation was derived that makes possible predictions of partition coefficient in binary mobile phases with different proportions of organic solvent to water based on some simple regression analysis. The LC separation for the derivatised alcohols containing higher carbon alcohols showed good reproducibility on a reversed-phase C18 column with gradient elution. The detection limits (excitation at 335 nm, emission at 360 nm) for derivatised alcohols (signal-to-noise ratio=3:1) were in the range of 0.1-0.4 pg per injection.

Microwave-assisted extract process for flavonoids from ginger (FG) was studied. Influences of concentration of extracting agent, microwave power, material ratio and irradiation time on the extraction were investigated. From orthogonal experiments the optimum extracting parameters were determined as follows: microwave power, 640W, concentration of alcohol, 80%, the materials ratio, 1:30 (W: V) and irradiation time, 25s. Under this optimal condition, the yield of flavonoids was 16.97 mg/g. In this study, the antioxidant activity of FG was evaluated by various methods with BHT and ascorbic acid as control standards. Antioxidant experiments showed that FG exhibited a strong DPPH radical scavenging activity, reducing power and inhibition of lipid peroxidation activity, and antioxidant activity increased with increasing concentration.