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Efficient occlusion of particulate additives into a single crystal has garnered an ever‐increasing attention in materials science because it offers a counter‐intuitive yet powerful platform to make crystalline nanocomposite materials with emerging properties. However, precisely controlling the spatial distribution of the guest additives within a host crystal remains highly challenging. We herein demonstrate a unique, straightforward method to engineer the spatial distribution of copolymer nanoparticles within calcite (CaCO3) single crystals by judiciously adjusting initial [Ca2+] concentration used for the calcite precipitation. More specifically, polymerization‐induced self‐assembly is employed to synthesize well‐defined and highly anionic poly(3‐sulfopropyl methacrylate potassium)41‐block‐poly(benzyl methacrylate)500 [PSPMA41‐PBzMA500] diblock copolymer nanoparticles, which are subsequently used as model additives during the growth of calcite crystals. Impressively, such guest nanoparticles are preferentially occluded into specific regions of calcite depending on the initial [Ca2+] concentration. These unprecedented phenomena are most probably caused by dynamic change in electrostatic interaction between Ca2+ ions and PSPMA41 chains based on systematic investigations. This study not only showcases a significant advancement in controlling the spatial distribution of guest nanoparticles within host crystals, enabling the internal structure of composite crystals to be rationally tailored via a spatioselective occlusion strategy, but also provides new insights into biomineralization. [ABSTRACT FROM AUTHOR]

2‐Acylindoles possess widespread applications in functional chemicals. However, the convenient and selective synthesis of such important substructures has to date remained a challenge. Herein, a method to achieve 2‐acylindoles from sulfoxonium ylides with o‐aminoaryl aldehydes catalysed by Iridium has been developed with the merits of broad substrate scope, good functional tolerance, high efficiency and operational simplicity, which provides an alternative way to access functionalized indoles. [ABSTRACT FROM AUTHOR]

The persistent heavy precipitation during summer in 1998 and 2020 in the middle and lower reaches of the Yangtze River basin (MLYRB) caused the most influential floods in the region during recent 30 years. Previous studies paid lots of attention to those events by analysing the spatial–temporal distributions and the circulation backgrounds; however, the comparison of moisture contribution to summer precipitation in the MLYRB in 1998 and 2020 have rarely been well addressed. This study tracked the moisture sources of summer precipitation in 1998 and 2020 in the MLYRB based on an Eulerian moisture tracking model (WAM‐2layers) forced with ERA5 dataset and explored the similarities and differences of moisture transport and moisture contribution during the two periods. Results showed that the moisture contribution to summer precipitation in the MLYRB mainly transported by the southwest monsoon system, with the major sources extended across the Indo‐China Peninsula, the Bay of Bengal and the Arabian Sea, to the south Indian Ocean. During the summer of 1998 and 2020, increased moisture contributions were mainly from the southwestern sources, particularly the Indo‐China Peninsula and its surroundings. Meanwhile, decreased moisture contributions were found from the local recycling and the northeastern sources. In comparison with summer 1998, there were less moisture can be transported from the low‐latitude oceans (particularly the Arabian Sea and the Bay of Bengal) to the MLYRB during summer 2020, except for the Northwestern Pacific. [ABSTRACT FROM AUTHOR]

Biominerals can exhibit exceptional mechanical properties owing to their hierarchically‐ordered organic/inorganic nanocomposite structure. However, synthetic routes to oriented artificial biominerals of comparable complexity remain a formidable technical challenge. Herein we design a series of soft, deformable nanogels that are employed as particulate additives to prepare nanogel@calcite nanocomposite crystals. Remarkably, such nanogels undergo a significant morphological change—from spherical to pseudo‐hemispherical—depending on their degree of cross‐linking. This deformation occurs normal to the growth direction of the (104) face of the calcite and the underlying occlusion mechanism is revealed by in situ atomic force microscopy studies. This model system provides new mechanistic insights regarding the formation of oriented structures during biomineralization and offers new avenues for the design of synthetic nanocomposites comprising aligned anisotropic nanoparticles. [ABSTRACT FROM AUTHOR]

A nickel‐catalyzed transfer hydrogenation of aryl alkenes has been developed using hydrosilane as the hydrogen source. Sterically hindered disubstituted or trisubstituted alkenes were employed to test the efficiency of this transformation. Mechanism studies showed that hydrogenation took place smoothly with more sterically‐hindered trans‐alkenes. While uncongested cis‐alkenes could hardly convert to the alkanes but hydrosilylation products were generated instead. Moreover, certain amount of water was found to be a promotion for the protonation process and could partly serve as the hydrogen source. Not only for simple stilbenes, this easy handle protocol also showed tolerance for substrates involving other unsaturated groups as well as heterocycles. [ABSTRACT FROM AUTHOR]

3‐Acylquinolines possess widespread applications in functional chemicals. However, the convenient and selective synthesis of such important substructures has to date remained a challenge. Herein, we report a method to access 3‐acylquinolines from α, β‐unsaturated ketones and 2‐aminoaryl alcohols in one pot with a copper nanocatalyst supported on nitrogen‐silica‐doped carbon (Cu/N−SiO2−C). Mechanistically, the construction of the product involves a cascade procedure including radical‐type oxidation of 2‐aminoaryl alcohols, aza‐Michael addition and annulation. This developed protocol proceeds with merits of mild reaction conditions, good functional group tolerance, earth‐abundant and reusable copper catalyst, easily available stocks and O2 as the sole oxidant, which provides an alternative way for the sustainable synthesis of quinoline derivatives. [ABSTRACT FROM AUTHOR]

Objective: To investigate the epidemiology, clinical features, treatment and outcome of Noninvasive ventilation (NIV)‐treated acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients in secondary hospitals of Shanghai. Method: Relying on Shanghai alliances for respiratory diseases, a retrospective observational study was performed in 34 secondary hospitals of Shanghai. The AECOPD patients treated with NIV and admitted to the respiratory department or respiratory intensive care unit were recruited between December 1, 2016, and November 30, 2017. Results: There were 555 patients finally recruited in this study. The age was 75.8 ± 9.6 years old and 380 patients (68.5%) were male. 70.5% of all patients had respiratory acidosis (pH <7.35). 55.3% of all patients received nebulised bronchodilator and 77.7% were treated with systemic or inhaled corticosteroids during hospitalisation. 525 patients (94.6%) recovered successfully and the mortality was 3.2%. The hospitalisation was 15.3 ± 6.7 days and hospital expenses were 22 911 ± 13 595 RMB. Inadequate and nonstandard drug treatments were the most important problems during management. Conclusion: The NIV can be successfully used for AECOP patients in local hospitals of Shanghai, but accompanied by high costs and long hospital stays. However, the treatments for exacerbation and stable COPD patients are still insufficient. [ABSTRACT FROM AUTHOR]

A nonreciprocal‐amplified scheme for signal transmission is proposed in a coupled rotation‐cavity system, where the two cavities rotate with opposite directions, and an optical parametric amplifier (OPA) is attached to one cavity. The coupling between cavities can effectively compensate and enhance the frequency shift of the Sagnac effect, and a perfect nonreciprocity can be achieved. Owing to the introduction of an OPA medium, eigenvalues of the dynamic matrix exhibit exceptional points (EPs), and the amplified‐nonreciprocal transmission can be obtained around EPs. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous catalyst nickel oxide supported on graphene nanoplatelets (NiO/Gr) has been developed for the aerobic and additive‐free dehydrogenation of N‐heterocycles. This catalyst was easily prepared by atomic layer deposition from nickel(II) diketonate–diamine and ozone, which has advantages of excellent activity, low metal loading, simple preparation, stability for multiple reuse. The reactions proceed in good yields with broad substrate scope under mild conditions by using tiny quantity of catalyst. Interestingly, pharmaceutically relevant tetrahydro‐β‐carboline derivative can also be oxidized successfully to afford the important intermediate. The control experiments suggest that this catalytic dehydrogenation experiences radical‐type oxidation. [ABSTRACT FROM AUTHOR]

In the conventional scheme of generating strong mechanical squeezing by the joint effect between mechanical parametric amplification and sideband cooling, the resolved sideband condition is required so as to overcome the quantum backaction heating. In the unresolved sideband regime, to suppress the quantum backaction, a χ(2) nonlinear medium is introduced to the cavity. The result shows that the quantum backaction heating effect caused by unwanted counter‐rotating term can be completely removed. Hence, the strong mechanical squeezing can be obtained even for the system far from the resolved‐sideband regime. [ABSTRACT FROM AUTHOR]

Celastrol, a pentacyclic tritepene extracted from Tripterygium Wilfordi plant, showing potent liver protection effects on several liver‐related diseases. However, the anti‐inflammatory potential of celastrol in liver fibrosis and the detailed mechanisms remain uncovered. This study was to investigate the anti‐inflammatory effect of celastrol in liver fibrosis and to further reveal mechanisms of celastrol‐induced anti‐inflammatory effects with a focus on AMPK‐SIRT3 signalling. Celastrol showed potent ameliorative effects on liver fibrosis both in activated hepatic stellate cells (HSCs) and in fibrotic liver. Celastrol remarkably suppressed inflammation in vivo and inhibited the secretion of inflammatory factors in vitro. Interestingly, celastrol increased SIRT3 promoter activity and SIRT3 expression both in fibrotic liver and in activated HSCs. Furthermore, SIRT3 silencing evidently ameliorated the anti‐inflammatory potential of celastrol. Besides, we found that celastrol could increase the AMPK phosphorylation. Further investigation showed that SIRT3 siRNA decreased SIRT3 expression but had no obvious effect on phosphorylation of AMPK. In addition, inhibition of AMPK by employing compound C (an AMPK inhibitor) or AMPK1α siRNA significantly suppressed SIRT3 expression, suggesting that AMPK was an up‐stream protein of SIRT3 in liver fibrosis. We further found that depletion of AMPK significantly attenuated the inhibitory effect of celastrol on inflammation. Collectively, celastrol attenuated liver fibrosis mainly through inhibition of inflammation by activating AMPK‐SIRT3 signalling, which makes celastrol be a potential candidate compound in treating or protecting against liver fibrosis. [ABSTRACT FROM AUTHOR]

A new one-pot synthetic protocol, enabling the facile access to 2-alkylaminoquinolines and 1,8-naphthyridines by successive ruthenium-catalyzed dehydrogenative annulation and N-alkylation processes, has been demonstrated. A series of 2-aminoarylmethanols were efficiently converted in combination with different types of nitriles and alcohols into various desired products in moderate to excellent yields after isolation. Advantageously, the synthesis proceeds with high atom-efficiency, broad substrate scope, operational simplicity, no need for external hydrogen sources and less environmentally benign halogenated reagents, thus offering a practical approach to access these two types of compounds that are currently difficult to prepare with the conventional methods. [ABSTRACT FROM AUTHOR]

Via a base-catalyzed hydrogen-transfer coupling reaction, a straightforward synthesis of 2-arylquinoxalines from readily available 2-nitroanilines with only an equimolar amount of monoalcohols has been developed. The synthetic protocol proceeds in a step- and atom-economic fashion together with the advantages of operational simplicity, broad substrate scope, water as the only byproduct, and no need for noble transition-metal catalysts, external reducing agents, or less environmentally benign halogenated reagents, offers a highly practical approach to access 2-arylquinoxalines. [ABSTRACT FROM AUTHOR]

A squeezed‐coherent‐cat state (SCCS) in a mechanical system not only plays an important role for macroscopic quantum coherence, but also can be a carrier for quantum information. A scheme to generate a SCCS in a two‐mode optomechanical system is proposed, in which the modulated hopping interaction of two cavities is introduced. The two cavity modes couple with the same mechanical mode with linear and quadratic interaction, respectively. The SCCS is analytically deduced under an appropriate initial state, and the average phonon number and the parameter of squeeze are numerically calculated. Wigner function shown the properties of superposition and squeezing is plotted. Including the dissipation of the environment, the results show that a high quality mechanical resonator and a low noise environment are required to obtain high fidelity. [ABSTRACT FROM AUTHOR]

The article discusses the hydrogen transfer mediated direct ß-alkylation of aryl-1,8-naphthyridines with alcohols in transition metal catalyst free conditions.

The article presents information on the synthesis of 2-arylquinoxalines from 2-nitroanilines.

A novel synthesis of tetrahydronaphthyridines from o-aminopyridyl methanols and alcohols is developed. [ABSTRACT FROM AUTHOR]

This methodology can be employed to synthesize a wide range of target compounds and to introduce different functional groups into the β-aminoketone skeleton. [ABSTRACT FROM AUTHOR]

This is the first report about Ullmann-type N-arylation of 2-amino-cyanopyridines (I) with aryl halides using a bis(phenanthroline)-copper(I) complex as catalyst. [ABSTRACT FROM AUTHOR]

The reaction proceeds regioselectively in the case of disubstituted anilines such as (VI) or β-naphthylamine (IV). [ABSTRACT FROM AUTHOR]