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Oxime ethers are attractive compounds in medicinal scaffolds due to the biological and pharmaceutical properties, however, the crucial and widespread step of industrial oxime formation using explosive hydroxylamine (NH2OH) is insecure and troublesome. Herein, we present a convenient method of oxime ether synthesis in a one‐pot tandem electrochemical system using magnesium based metal‐organic framework‐derived magnesium oxide anchoring in self‐supporting carbon nanofiber membrane catalyst (MgO‐SCM), the in situ produced NH2OH from nitrogen oxides electrocatalytic reduction coupled with aldehyde to produce 4‐cyanobenzaldoxime with a selectivity of 93 % and Faraday efficiency up to 65.1 %, which further reacted with benzyl bromide to directly give oxime ether precipitate with a purity of 97 % by convenient filtering separation. The high efficiency was attributed to the ultrafine MgO nanoparticles in MgO‐SCM, effectively inhibiting hydrogen evolution reaction and accelerating the production of NH2OH, which rapidly attacked carbonyl of aldehydes to form oximes, but hardly crossed the hydrogenation barrier of forming amines, thus leading to a high yield of oxime ether when coupling benzyl bromide nucleophilic reaction. This work highlights the importance of kinetic control in complex electrosynthetic organonitrogen system and demonstrates a green and safe alternative method for synthesis of organic nitrogen drug molecules. [ABSTRACT FROM AUTHOR]

Plant protein‐based adhesives, particularly those derived from soybean meal (SM), have been available for various product applications. However, the high cost of SM has limited large‐scale manufacturing, despite sufficient production capacity. Peony seed meal (PSM) is abundant in proteins, polysaccharides, and polyphenols, the protein in PSM contains highly hydrophobic amino acids, resulting in low water solubility and water holding capacity. It is worth investigating whether the unique composition of hydrophobic amino acids in PSM protein can enhance the water resistance of PSM‐based adhesives. Additionally, the lower price of PSM, which is approximately two‐thirds of the cost of SM, makes it a more valuable raw material for adhesives. Herein, we report a simple and practical approach for preparing PSM‐based wood adhesives by utilizing the highly active cross‐linking agent of polyamidoamine‐epichlorohydrin (PAE). The results showed PSM‐based adhesives possessed excellent adhesion, especially the adhesive of "PSM‐36%", with the wet bond strength and the aged bond strength reaching 1.60 and 0.83 MPa, respectively, meeting the standards outlined for indoor‐use plywood (≥0.98 MPa). Mechanistic studies indicated that the adhesion mechanism of such PSM‐based adhesives might involve high solid content, low viscosity, high thermal stability, and the formulation of covalent bonds and hydrogen bond networks. [ABSTRACT FROM AUTHOR]

Inorganic nitrogen oxide (NOx) species, such as NO, NO2, NO3−, NO2− generated from the decomposition of organic matters, volcanic eruptions and lightning activated nitrogen, play important roles in the nitrogen cycle system and exploring the origin of life. Meanwhile, excessive emission of NOx gases and residues from industry and transportation causes troubling problems to the environment and human health. How to efficiently handle these wastes is a global problem. In response to the growing demand for sustainability, scientists are actively pursuing sustainable electrochemical technologies powered by renewable energy sources and efficient utilization of hydrogen energy to convert NOx species into high‐value organonitrogen chemicals. In this minireview, recent advances of electrocatalytic systems for NOx species valorization in organonitrogen synthesis are classified and described, such as amino acids, amide, urea, oximes, nitrile etc. that have been widely applied in medicine, life science and agriculture. Additionally, the current challenges including multiple side reactions and complicated paths, viable solutions along with future directions ahead in this field are also proposed. The coupling electrocatalytic systems provide a green mode for fixing nitrogen cycle bacteria and bring enlightenment to human sustainable development. [ABSTRACT FROM AUTHOR]

Pyridine oximes produced from aldehyde or ketone with hydroxylamine (NH2OH) have been widely applied in pharmaceutics, enzymatic and sterilization. However, the important raw material NH2OH exhibits corrosive and unstable properties, leading to substantial energy consumption during storage and transportation. Herein, this work presents a novel method for directly synthesizing highly valuable pyridine oximes using in situ generated NH2OH from electrocatalytic NO reduction with well‐design nanofiber membranes (Al‐NFM) derived from NH2‐MIL‐53(Al). Particularly, 2‐pyridinealdoxime, the precursor of antidote pralidoxime (2‐PAM) for nerve agents suffering from scarcity and high cost, was achieved with a Faraday efficiency up to 49.8 % and a yield of 92.1 %, attributing to the high selectivity of NH2OH production on Al‐NFM, further easily reacted with iodomethane to produce 2‐PAM. This study proposes a creative approach, having wide universality for synthesizing pyridine and other oximes with a range of functional groups, which not only facilitates the conversion of exhaust gas (NO) and waste water (NO2−) into valuable chemicals especially NH2OH production and in situ utilization through electrochemistry, but also holds significant potential for synthesis of neuro detoxifying drugs to humanity security. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative disease characterized by cartilage wear and degradation. Ginkgolide K (GK) is a natural compound extracted from Ginkgo biloba leaves and possesses anti‐inflammatory and anti‐apoptotic effects. We found that the biological characteristics of GK were highly consistent with those of OA medications. This study aimed to determine and verify the therapeutic effect of GK on OA and mechanism of its therapeutic effect. For the in vivo experiment, OA rats were regularly injected in the articular cavity with GK, and the curative effects were observed after 4 and 8 weeks. For the in vitro experiment, we treated OA chondrocytes with different concentrations of GK and then detected the related indices of OA. Through the in vivo and in vitro experiments, we found that GK could promote the production of major components of the cartilage extracellular matrix. Transcriptome sequencing revealed that GK may activate hypoxia‐inducible factor 1 alpha via the hypoxia signaling pathway, which, in turn, activates yes‐associated protein and inhibits apoptosis of OA chondrocytes. GK has a therapeutic effect on OA and, therefore, has the potential to be developed into a new drug for OA treatment. [ABSTRACT FROM AUTHOR]

Few investigations of river evolution have incorporated the series of upper vortex flow disturbances induced by quasi‐knickpoints, and it is unclear whether the regulating ability of riparian vegetation in maintaining meandering channel patterns is valid. In this study, we therefore conducted meander evolution experiments to confirm the effects of vegetation species and vegetation strength on this complex system. Two nonleguminous plants with salinity and alkalinity resistance had non‐uniform degrees of normal seedling growth and different root network lengths. Our findings show that braided swales formed between the upstream developing zone of the vortex flow and the nearest bend and the riparian vegetation generally consolidated the single‐thread channel planform without branching outward under the conditions of flooding flow. Transverse point bars on inner banks were replaced by downstream scroll bars in the overall channel for long time, unless riparian vegetation and flood scour were coupled. Shallow‐rooted plants were inadequate to withstand the inner‐banks being cut by the upper vortex flow. Deep‐rooted plants can significantly stabilize bank lines and thalwegs but are vulnerable to locally low vegetation coverage. Using evolutionary spectral analysis based on thalwegs, we found that the streamwise high‐frequency distribution of bed topography was primarily concentrated downstream of the bifurcation interface when a flood was present in the unvegetated scenario, shrank to the isolated turning interface of the upper reach and the large‐scale spiral swale of the lower reach in the shallow‐rooted scenario and stood out along the area disturbed by bare roots in the deep‐rooted scenario. This experimental study broadens our understanding of vegetation effects in hydro‐bio‐geomorphological system engineering. [ABSTRACT FROM AUTHOR]

The conversion of industrial exhaust gases of nitrogen oxides into high‐value products is significantly meaningful for global environment and human health. And green synthesis of amino acids is vital for biomedical research and sustainable development of mankind. Herein, we demonstrate an innovative approach for converting nitric oxide (NO) to a series of α‐amino acids (over 13 kinds) through electrosynthesis with α‐keto acids over self‐standing carbon fiber membrane with CoFe alloy. The essential leucine exhibits a high yield of 115.4 μmol h−1 corresponding a Faradaic efficiency of 32.4 %, and gram yield of products can be obtained within 24 hours in lab as well as an ultra‐long stability (>240 h) of the membrane catalyst, which could convert NO into NH2OH rapidly attacking α‐keto acid and subsequent hydrogenation to form amino acid. In addition, this method is also suitable for other nitrogen sources including gaseous NO2 or liquidus NO3− and NO2−. Therefore, this work not only presents promising prospects for converting nitrogen oxides from exhaust gas and nitrate‐laden waste water into high‐value products, but also has significant implications for synthetizing amino acids in biomedical and catalytic science. [ABSTRACT FROM AUTHOR]

How to transfer industrial exhaust gases of nitrogen oxides into high‐values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α‐amino acids from nitric oxide (NO) by reacting with α‐keto acids through electrocatalytic process with atomically dispersed Fe supported on N‐doped carbon matrix (AD‐Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mgcat−1 is delivered at −0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X‐ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α‐keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α‐amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO3−). Our findings not only provide a creative method for converting nitrogen oxides into high‐valued products, which is of epoch‐making significance towards artificial synthesis of amino acids, but also benefit in deploying near‐zero‐emission technologies for global environmental and economic development. [ABSTRACT FROM AUTHOR]

New Findings What is the topic of this review? This review summarizes chemoreflex physiology in health and disease, with specific focus on chemoreflex-mediated pathophysiology in obstructive and central sleep apnoea., What advances does it highlight? Chemoreflex mechanisms are thought to contribute significantly to the pathophysiology and adverse outcomes seen in sleep apnoea. Clinical implications of altered chemoreflex function in sleep apnoea from recent studies in humans, including cardiac arrhythmias, coronary artery disease, systolic/diastolic heart failure and sudden cardiac death are highlighted., Activation of the chemoreflex in response to hypoxaemia results in an increase in sympathetic neural outflow. This process is predominantly mediated by the peripheral chemoreceptors in the carotid bodies and is potentiated by the absence of the sympatho-inhibitory influence of ventilation during apnoea, as is seen in patients with sleep apnoea. In these patients, repetitive nocturnal hypoxaemia and apnoea elicit sympathetic activation, which may persist into wakefulness and is thought to contribute to the development of systemic hypertension and cardiac and vascular dysfunction. Chemoreflex activation could possibly lead to adverse cardiovascular outcomes, such as nocturnal myocardial infarction, systolic and/or diastolic heart failure, cardiac arrhythmias and sudden death in patients with sleep apnoea. This review summarizes chemoreflex physiology in health and disease, with specific focus on chemoreflex-mediated pathophysiology in obstructive and central sleep apnoea. Measurement of the chemoreflex response may serve as a potential avenue for individualized screening for cardiovascular disease. Whether modulation of this response in sleep apnoea may aid in the prevention and treatment of adverse cardiovascular consequences will require further study. [ABSTRACT FROM AUTHOR]