We report a Pd-catalyzed intermolecular hydrophosphinylation of 1,3-dienes to afford chiral allylic phosphine oxides. Commodity dienes and air stable phosphine oxides couple to generate ...organophosphorus building blocks with high enantio- and regiocontrol. This method constitutes the first asymmetric hydrophosphinylation of dienes.
Pancreatic cancer (PC) is a serious malignancy with high mortality and poor prognosis due to nonspecific incipient symptoms and early metastasis. Also, increasing evidence indicates that a panel of ...genes is newly identified in the pathogenesis of PC. As is a regulatory subunit, elevated cyclin B1 (CCNB1) expression has been detected in different cancers including PC. This study is designed to investigate the effects of CCNB1 silencing on cell cycle, senescence, and apoptosis through the p53 signaling pathway in PC. PC tissues and normal pancreatic tissues were collected. Cells were transfected and assigned into different groups. The expressions of CCNB1, p53, MDM2, Bax, caspase‐9, caspase‐3, and p21 in tissues and cells were detected by reverse transcription quantitative polymerase chain reaction and western blot analysis. β‐Galactosidase staining, MTT assay, and flow cytometry were conducted to test cell senescence, proliferation, cell cycle, and apoptosis. PC tissues showed higher expressions of CCNB1 and MDM2 and lower expressions of Bax, caspase‐9, caspase‐3, and p21. Cells transfected with shCCNB1 had lower expressions of CCNB1 and MDM2, whereas higher expressions of Bax, caspase‐9, caspase‐3, p53, and p21. The shCCNB1 group had decreased proliferation and S‐phase cell proportion and increased apoptosis, senescence, and G0/G1‐phase cell proportion. The PFT‐α group showed higher expressions of MDM2 and lower expressions of Bax, caspase‐9, caspase‐3, p53, and p21. The PFT‐α group had increased proliferation and S‐phase cell proportion and declined apoptosis, senescence, and G0/G1‐phase cell proportion. CCNB1 silencing inhibits cell proliferation and promotes cell senescence via activation of the p53 signaling pathway in PC.
CCNB1 silencing inhibits cell proliferation and promotes cell senescence via activation of the p53 signaling pathway in pancreatic cancer.
The invention and application of the electric power technology triggered the second industrial revolution in human history, which marked the human society entered the age of electricity. Electricity ...provides the sustainable power for economic and social development. With the rapid development of economy, the electricity consumption is also increasing. The increase of electricity consumption has further promoted the progress of the industrial economy. In order to achieve the goal of improving the level of economic development while reducing energy consumption, it is necessary to reveal the relationship between electricity consumption and economic growth. This study is an extensive overview of the literature surrounding this topic. In this paper, we focus on the relationship between electricity consumption and economic growth in China. We first analyze the general situation of China's electricity consumption and economic development. Then we explore the relationship between China's electricity consumption and economic growth from three dimensions, i.e., the time dimension, the regional dimension and the industrial dimension. Finally, we study the key issues in the research of the relationship between electricity consumption and economic growth, including variable selection, model construction and results discussion. This work suggests that the nature of the nexus in China should and can be explored from a wider perspective, by developing a suitable integrated methodological framework.
Microglia are endogenous immune cells in the brain, and their pyroptosis and phenotype dichotomy are proved to play roles in neurodegenerative diseases. We investigated whether and how hypoxia ...affected pyroptosis and phenotype polarization in mouse microglia. Primary mouse microglia and BV2 microglia were exposed to hypoxia. Pyroptosis and M1/M2 phenotype were assessed by measuring gasdermin D truncation and M1/M2 surface marker expression. Mechanisms including purinergic ionotropic receptor (P2XR), peroxisome proliferator‐activated receptor coactivator‐1α (PGC‐1α) and NOD‐like receptor protein 3 (NLRP3) inflammasome were investigated. We reported hypoxia (90% N2, 5% O2 and 5% CO2) induced pyroptosis and promoted M1 phenotype polarization in primary mouse microglia and BV2 microglia, and the effect appeared after 6 h exposure. Although hypoxia (90% N2, 5% O2 and 5% CO2, 6 h) had no effect on P2X1R and P2X7R expression, it increased P2X4R expression and decreased PGC‐1α expression. Interestingly, blockade of P2X4R or P2X7R abolished hypoxia‐modulated PGC‐1α expression, pyroptosis and M1 polarization. PGC‐1α overexpression or overactivation alleviated hypoxia‐induced pyroptosis and M1 polarization, while PGC‐1α knockdown or deactivation promoted pyroptosis and M1 polarization under normoxic situation. Further, hypoxia induced NLRP3 expression and activated caspase‐1 and induced the phosphorylation of NF‐κB and reduced the phosphorylation of STAT3/6. NLRP3 inhibitor and caspase‐1 inhibitor abolished hypoxia‐induced pyroptosis, while NF‐κB inhibitor and STAT phosphorylation inducer ameliorated hypoxia‐induced M1 polarization. In addition, NF‐κB activator and STAT3/6 inhibitor caused microglia M1 polarization under normoxic situation. We concluded in cultured mouse microglia, hypoxia may induce pyroptosis via P2XR/PGC‐1α/NLRP3/caspase‐1 pathway and trigger M1 polarization through P2XR/PGC‐1α/NF‐κB/STAT3/6 pathway.
In this Article, we expand upon the catalytic hydrothiolation of 1,3-dienes to afford either allylic or homoallylic sulfides with high regiocontrol. Mechanistic studies support a pathway in which ...regioselectivity is dictated by the choice of counterion associated with the Rh center. Non-coordinating counterions, such as SbF6 –, allow for η4-diene coordination to Rh complexes and result in allylic sulfides. In contrast, coordinating counterions, such as Cl–, favor neutral Rh complexes in which the diene binds η2 to afford homoallylic sulfides. We propose mechanisms that rationalize a fractional dependence on thiol for the 1,2-Markovnikov hydrothiolation while accounting for an inverse dependence on thiol in the 3,4-anti-Markovnikov pathway. Through the hydrothiolation of an essential oil (β-farnesene), we achieve the first enantioselective synthesis of (−)-agelasidine A.
Image dehazing is a crucial image processing step for outdoor vision systems. However, images recovered through conventional image dehazing methods that use either haze-relevant priors or heuristic ...cues to estimate transmission maps may not lead to sufficiently accurate haze removal from single images. The most commonly observed effects are darkened and brightened artifacts on some areas of the recovered images, which cause considerable loss of fidelity, brightness, and sharpness. This paper develops a variational image dehazing method on the basis of a color-transfer image dehazing model that is superior to conventional image dehazing methods. By creating a color-transfer image dehazing model to remove haze obscuration and acquire information regarding the coefficients of the model by using the devised convolutional neural network-based deep framework as a supervised learning strategy, an image fidelity, brightness, and sharpness can be effectively restored. The experimental results verify through quantitative and qualitative evaluations of either synthesized or real haze images, and the proposed method outperforms existing single image dehazing methods.
Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health
. Bats have been recognized as one of the most important reservoirs for emerging ...viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS)
. Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.
Two-dimensional materials such as graphene and transition metal dichalcogenides have been identified and drawn much attention over the last few years for their unique structural and electronic ...properties. However, their rise begins only after these materials are successfully isolated from their layered assemblies or adhesive substrates into individual monolayers. Mechanical exfoliation and transfer are the most successful techniques to obtain high-quality single- or few-layer nanocrystals from their native multi-layer structures or their substrate for growth, which involves interfacial peeling and intralayer tearing processes that are controlled by material properties, geometry and the kinetics of exfoliation. This procedure is rationalized in this work through theoretical analysis and atomistic simulations. We propose a criterion to assess the feasibility for the exfoliation of two-dimensional sheets from an adhesive substrate without fracturing itself, and explore the effects of material and interface properties, as well as the geometrical, kinetic factors on the peeling behaviors and the torn morphology. This multi-scale approach elucidates the microscopic mechanism of the mechanical processes, offering predictive models and tools for the design of experimental procedures to obtain single- or few-layer two-dimensional materials and structures.
•Investigates online and offline bicycle sharing service quality perceived by customers.•Examines the influences of bicycle sharing service quality on customer satisfaction.•Uncovers the moderating ...effect of gender on bicycle sharing service quality.
The widespread usage of smart bicycle-sharing and the dockless bicycle design creates a new development trend for the public transportation service. Drawing on service quality theory, this study proposes a theoretical model to uncover the impacts of five online to offline service qualities on user satisfaction and behavioral intention with regard to dockless bicycle-sharing. Our results suggest that location reliability, prompt response, customization, transaction assurance and vividness exhibit different extent of influences on customers’ confirmation of a bicycle-sharing service. Moreover, customers’ confirmation is positively related to perceived usefulness and satisfaction, which further enhances their continuance intention. A multi-group analysis suggests that males and females react differently to the five service qualities. Particularly, male users are more likely affected by location reliability and vivid appearance, whilst female users focus more on transaction assurance.
NOx gas sensor based on Si-doped graphene
Si-doped graphene nanosheets (SiGNS) has been successfully prepared and the as-prepared SiGNS-400 shows excellent NOx sensing performance.
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...•Si-doped graphene nanosheets realized the NOx gas detection.•The doped Si species were verified as the active sites for NOx sensing.•Si atom has been successfully doped into graphene’s carbon network.•The sensing selectivity of Si doped graphene to NOx is very unique.
Si-doped graphene nanosheets (SiGNSs) were constructed via high temperature annealing of the precursor mixture (the graphene oxide and tetraethoxysilane) in a sealed glass ampoule. Si-doped graphene nanosheets annealed at 400 °C (SiGNS-400) exhibited excellent NOx sensing ability with a high response value (21.5%–50 ppm of NO2), a fast response (126s), a fast recovery (378s), a broad detectable concentration range (300 ppm∼18 ppb) and outstanding selectivity. The doped Si atoms play a key role in NOx sensing. The sensor prepared by SiGNS-400 detected NOx not only in environments with a single harmful gas but also in complex environments containing several harmful gases. The detectable concentration range of the SiGNS-400 sensor decreased with increasing operating temperature.
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