Ring-opening reaction via selective cleavage of C-C bond is known as a powerful strategy for construction of complex molecules. Complementary to the ionic process focusing on mostly small ring ...systems, radical-mediated C-C bond cleavage offers a solution for further diverse enantioselective functionalization benefited from its mild conditions, whereas such asymmetric transformations are still limited to three-membered rings so far. Herein, we describe radical-mediated ring-opening and enantioselective cyanation of four- and five-membered cycloketone oxime esters to access chiral 1,5- and 1,6-dinitriles. Employment of dual photoredox/copper catalysis is essential for the asymmetric ring-opening cyanation of cyclopentanone oxime esters. Both reactions proceed under mild conditions giving chiral dinitriles in high yields and enantioselectivity with low catalyst loading and broad substrate scope. The products dinitriles can be converted to valuable optically active diamides and diamines. Mechanistic studies indicate that the benzylic radical generated via C-C single bond cleavage is involved in the catalytic cycle.
•The potential gains and carbon emissions reduction of carbon trading are detected.•Three scenarios of carbon trading schemes are considered and compared.•Sectoral trading may create potential gains ...of 268.02 trillion yuan in 2006–2015.•Carbon emissions may decrease by 17.17 billion tonnes under sectoral trading scheme.•Sectoral trading decreases industrial carbon intensity by 19.80% during 2015–2020.
Carbon trading is an important market tool in driving growth and carbon dioxide emissions reduction in industrial sectors in China. This paper attempts to assess the impacts of carbon trading on economic output and carbon dioxide emissions reduction in China’s industrial sectors by employing the data envelopment analysis (DEA) based optimization models, based on three carbon trading schemes, i.e., no trading (NT), sectoral trading (ST), and sectoral-and-temporal trading (STT) during 2006–2015. Comparing with the no-trading scheme, the results indicate that, (1) the ST and STT schemes may create potential gains of 268.02 and 612.26 trillion yuan in the whole industrial during the study period, i.e., the industrial value-added would be increased by 55.17% and 73.76%, respectively; (2) the ST and STT schemes could reduce 17.17 and 19.22 billion tonnes of carbon dioxide emissions, respectively, accounting for 58.30% and 65.25% of emissions reduction in the whole industry; and (3) if carbon trading were adopted in China since 2006, its carbon intensity of industrial sectors would decrease by 34.89%, 47.44% and 19.80% under the ST scheme, and 58.93%, 31.50% and 10.25% under the STT scheme during the11th, 12th and 13th Five-Year Plan periods, respectively.
Nanoelectrodes allow precise and quantitative measurements of important biological processes at the single living‐cell level in real time. Cylindrical nanowire electrodes (NWEs) required for ...intracellular measurements create a great challenge for achieving excellent electrochemical and mechanical performances. Herein, we present a facile and robust solution to this problem based on a unique SiC‐core–shell design to produce cylindrical NWEs with superior mechanical toughness provided by the SiC nano‐core and an excellent electrochemical performance provided by the ultrathin carbon shell that can be used as such or platinized. The use of such NWEs for biological applications is illustrated by the first quantitative measurements of ROS/RNS in individual phagolysosomes of living macrophages. As the shell material can be varied to meet any specific detection purpose, this work opens up new opportunities to monitor quantitatively biological functions occurring inside cells and their organelles.
Nanoelectrodes for biology: A facile and robust strategy for the fabrication of high performance nanowire electrodes (NWEs) was developed. The NWEs allowed the measurement of reactive oxygen and nitrogen species (ROS/RNS) within individual phagolysosomes inside living macrophages.
In today’s information explosion, simple text and pictures have long lost the market, replaced by the multidimensional expression form which integrates text, pictures, sound and other elements and ...mobilizes people’s vision, hearing, smell and other senses. Therefore, in the context of digital technology, this paper deeply explores the innovative propagation modes of short video works by establishing the CONVLSTM propagation model. The results show that the innovation of the similarity symbol system in the content of short video works is 65%. The innovation of symbol interpretation in the content of short video works is 73%. Then, with respect to the form strategy of short video works, the innovations of short video works on Weibo, Douyin, Kuaishou and Wechat platforms are 54%, 93%, 24% and 45% respectively. Therefore, it is concluded that the unique expression of Douyin short video works is the most innovative point, which differentiate from the traditional TV-style short video works on Wechat and Weibo platforms.
This paper first studied the association rule algorithm model’s mining steps and algorithm features and improved the algorithm by quantifying attributes and frequent clustering. Then, the “Internet ...+” English teaching scheme for agricultural majors is proposed, the corresponding teaching system is designed, and a fresh approach to teaching English is developed. The impact of the teaching reform was evaluated using the indices of English efficiency, ability change, and learning status. The mean values of students’ learning attitude, interest, strategy and efficiency increased by 0.299, 0.844, 0.522 and 1.074, respectively, after using the “Internet + Classroom” teaching mode, which indicates that the new English teaching mode has significant teaching effects. This study provides new ideas and practical experience for reforming English courses in agriculture.
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•It is the first time to report visible light photodegradation of tetracycline (TC) over TiO2.•56.7% of TC was removed by TiO2 under visible (500 nm) light irradiation.•Different ...active species were found in TC degradation under different light irradiations.•UV and visible light irradiations generated different degradation products.
TiO2 is widely exploited as a photocatalyst to degrade antibiotic residues in water under UV irradiation, but it is inefficient for visible light photocatalysis due to its large band gap. Herein, it is the first time to report the photodegradation of tetracycline (TC) over TiO2 under visible light irradiation. 25.1% of removal efficiency for TC was achieved even under 700 nm light irradiation. Furthermore, it was demonstrated that O2− species, which were generated from photoexciting of a surface complex between TC molecules and TiO2, played a critical role in the visible light photocatalytic degradation of TC. In addition, it was found that the visible light photocatalytic degradation generated different active species and intermediate products from those under UV irradiation. N-doped TiO2 exhibited even better performance for visible-light photocatalytic degradation of TC with higher removal efficiency and larger mineralization rate, which followed different degradation-mechanism.
In China, the dynamics of the central-local relations vary significantly within legislative, executive, and judicial branches. In the field of law enforcement oversight, signs of cooperative ...federalism have emerged, presenting a drastic contrast to the unitary system. The lacking of a legal basis to directly supervise local governments forces the National People's Congress Standing Committee to actively seek cooperation from local governments. Three different approaches have been applied by the top legislature to achieve the goal. Easing the resistance from local governments through delegating the oversight power represents a move of compromise. Removing hurdles affecting law enforcement, reducing law enforcement cost, and soliciting suggestions on statutory revision from localities is a form of reciprocity. Eliminating local protectionism, enhancing cross-regional law enforcement, and sharing law enforcement experiences is an act of altruism.
The maternal‐foetal interface is an immune‐privileged site where the semi‐allogeneic embryo is protected from attacks by the maternal immune system. Uterine macrophages are key players in ...establishing and maintaining pregnancy, and the dysregulation of the M1‐M2 subpopulation balance causes abortion. We separated two distinct mouse uterine macrophage subpopulations during early pregnancy, CD45+F4/80+CD206− M1‐like (M1) and CD45+F4/80+CD206+ M2‐like (M2) cells. The M1 preponderance was significantly exaggerated at 6 hours after lipopolysaccharide (LPS) treatment, and adoptive transfer of M2 macrophages partially rescued LPS‐induced abortion. RNA sequencing analysis of mouse uterine M2 versus M1 revealed 1837 differentially expressed genes (DEGs), among which 629 was up‐regulated and 1208 was down‐regulated. Histone deacetylase 9 (Hdac9) was one of the DEGs and validated to be significantly up‐regulated in uterine M2 as compared with M1. Remarkably, this differential expression profile between M1 and M2 was also evident in primary splenic macrophages and in vitro polarized murine peritoneal, bone marrow–derived and RAW 264.7 macrophages. In Hdac9/HDAC9 knockout RAW 264.7 and human THP‐1–derived macrophages, the expression of M1 differentiation markers was unchanged or decreased whereas M2 markers were increased compared with the wild‐type cells, and these effects were unrelated to compromised proliferation. Furthermore, Hdac9/HDAC9 ablation significantly enhanced the phagocytosis of fluorescent microspheres in M2 Raw 264.7 cells yet decreased the capacity of THP‐1‐derived M1 macrophages. The above results demonstrate that Hdac9/HDAC9 deficiency exaggerates M2 macrophage polarization in mouse and human macrophages, which may provide clues for our understanding of the epigenetic regulation on macrophage M1/M2 polarization in maternal‐foetal tolerance.
Aims and objectives
To investigate, for the first time, aberrant time‐varying local brain activity in nurses following night shift–related sleep deprivation (SD) and its association with memory ...decline.
Background
Prior studies have elucidated alterations in static local brain activity resulting from SD in the occupations outside medical profession.
Design
A longitudinal study followed the STROBE recommendations.
Methods
Twenty female nurses underwent resting‐state functional magnetic resonance imaging and memory function assessment (by Complex Figure Test (CFT) and the California Verbal Learning Test, Second Edition (CVLT‐II)) twice, once in a rested wakefulness (RW) state and another after SD. By combining the sliding‐window approach and amplitude of low‐frequency fluctuation (ALFF) analysis, the dynamic ALFF (dALFF) variability was calculated to reflect the characteristics of dynamic local brain activity.
Results
Poor performance on the CFT and CVLT‐II was observed in nurses with night shift–related SD. Reduced dALFF variability was found in a set of cognition‐related brain regions (including the medial/middle/superior frontal gyrus, anterior/posterior cingulate gyrus, precuneus, angular gyrus, orbitofrontal and subgenual areas, and posterior cerebellum lobe), while increased dALFF variability was observed in the somatosensory‐related, visual and auditory regions. SD‐related dALFF variability alterations correlated with changes in subjects' performance on the CFT and CVLT‐II.
Conclusions
Night shift–related SD disturbed dynamic brain activity in high cognitive regions and induced compensatory reactions in primary perceptual cortex. Identifying dALFF variability abnormalities may broaden our understanding of neural substrates underlying SD‐related cognitive alterations, especially memory dysfunction.
Relevance to clinical practice
Night shift–related SD is as an important occupational hazard affecting brain function in nurses. The effective countermeasure addressing the adverse outcomes of SD should be advocated for nurses.
Patient or public contribution
Patients or public were not involved in the design and implementation of the study or the analysis and interpretation of the data.
The first example of highly enantioselective fluoroarylation of gem‐difluoroalkenes with aryl halides is presented by using a new chiral sulfinamide phosphine (Sadphos) type ligand TY‐Phos. ...N‐Me‐TY‐Phos can be easily synthesized on a gram scale from readily available starting materials in three steps. Salient features of this work including readily available starting materials, good yields, high enantioselectivities as well as broad substrate scope make this approach very practical and attractive. Notably, the asymmetric synthesis of an analogue of a biologically active molecule is also reported.
Highly enantioselective fluoroarylation of gem‐difluoroalkenes with aryl halides is presented by using a new chiral sulfinamide phosphine (Sadphos) type ligand (TY‐Phos). The salient features of this reaction include readily available starting materials, high yields and enantioselectivity, and broad substrate scope.
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