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The asymmetrical growth of a single‐wall carbon nanotube (SWCNT) by introducing a change of a local atomic structure, is usually inevitable and supposed to have a profound effect on the chirality control and property tailor. However, the breaking of the symmetry during SWCNT growth remains unexplored and its origins at the atomic‐scale are elusive. Here, environmental transmission electron microscopy is used to capture the process of breaking the symmetry of a growing SWCNT from a sub‐2‐nm platinum catalyst nanoparticle in real‐time, demonstrating that topological defects formed on the side of a SWCNT can serve as a buffer for stress release and inherently break its axis‐symmetrical growth. Atomic‐level details reveal the importance of the tube‐catalyst interface and how the atom rearrangement of the solid‐state platinum catalyst around the interface influences the final tubular structure. The active sites responsible for trapping carbon dimers and providing enough driving force for carbon incorporation and asymmetric growth are shown to be low‐coordination step edges, as confirmed by theoretical simulations. [ABSTRACT FROM AUTHOR]

Introduction: Numerous studies have found that expert players anticipate better than novices. If more accurate prediction represents performance monitoring of experts, what are the advantages of elite basketball players in identifying and processing available cues? There is still a lack of sufficient evidence. This study examined the visual search in basketball players and explored the performance monitoring of action anticipation, adopting an expert–novice paradigm and eye‐movement technology. Methods: Forty basketball players were recruited in this study: 20 in the expert group and 20 in the novice group. Participants were asked to predict the outcome of videotaped basketball throws and their accuracy and eye‐movement characteristics were record. Results: The accuracy of the expert was significantly higher than that of the novice. The experts were able to instantly search and identify important cues in anticipation, and the gaze area of the experts was concentrated on the area of interest of the body. Additionally, the expert group showed long, repetitive, and rapid visual search of vital information, and improved their performance of the task. Conclusion: The experts could monitor the performance of prediction by grabbing vital shooting information (such as the body of a player). The results suggest the athletes and coaches that if they want to improve the ability of prediction, it may be useful to shift their focus of attention from ball trajectory to body action. [ABSTRACT FROM AUTHOR]

Despite widespread use of the deuterium isotope effect, selective deuterium labeling of chemical molecules remains a major challenge. Herein, a facile and general electrochemically driven, organic mediator enabled deuteration of styrenes with deuterium oxide (D2O) as the economical deuterium source was reported. Importantly, this transformation could be suitable for various electron rich styrenes mediated by triphenylphosphine (TPP). The reaction proceeded under mild conditions without transition‐metal catalysts, affording the desired products in good yields with excellent D‐incorporation (D‐inc, up to >99 %). Mechanistic investigations by means of isotope labeling experiments and cyclic voltammetry tests provided sufficient support for this transformation. Notably, this method proved to be a powerful tool for late‐stage deuteration of biorelevant compounds. [ABSTRACT FROM AUTHOR]

Forming high‐temperature α‐Al2O3 phase under soft sparking is an intriguing phenomenon in plasma electrolytic oxidation (PEO) of Al alloys, which contradicts the low energy input of the process. In this study, α‐Al2O3 doped with black CuO is formed beneath an amorphous white outer layer on Al–Cu–Li alloy by PEO in a dilute silicate electrolyte under soft sparking. In comparison, reddish coatings with dominating γ‐Al2O3 are formed under the conventional plasma discharges, although blackish inner layer with α‐Al2O3 can also be exposed by heavily polishing the samples. In order to know the underlying mechanism, temperatures at the coating surface and the underlying substrate have been monitored by a thermocouple under the conventional and soft sparking PEO regimes, respectively. Interestingly, high temperatures are detected in the case of soft sparking rather than PEO with strong discharges. The formation of CuO, quartz, and cristobalite within the soft sparking coating also supports the existence of high temperature. Hence, the formation of α‐Al2O3 under soft sparking can be resolved to the conventional thermal activation mechanism, without the need of seeking other plausible explanations. Thermal condition evaluation for soft sparking PEO suggests that values of the effective thermal conductivity during PEO process for the outer layer and the barrier layer at the coating/substrate interface might be lower than ∼0.05 and ∼0.0017 W m−1 K−1, respectively. It is believed that the amorphous structure of the outer and barrier layers effectively blocks the heat dissipation, facilitating the formation of a highly wear‐resistant inner layer with α‐Al2O3, CuO, and the other high‐temperature species under soft sparking. [ABSTRACT FROM AUTHOR]

Herein, an electrochemically driven NiH‐catalyzed reductive coupling of alkyl halides and alkyl alkenes for the construction of Csp3−Csp3 bonds is firstly reported. Notably, alkyl halides serve dual function as coupling substrates and as hydrogen sources to generate NiH species under electrochemical conditions. The tunable nature of this reaction is realized by introducing an intramolecular coordinating group to the substrate, where the product can be easily adjusted to give the desired branched products. The method proceeds under mild conditions, exhibits a broad substrate scope, and affords moderate to excellent yields with over 70 examples, including late‐stage modification of natural products and drug derivatives. Mechanistic insights offer evidence for an electrochemically driven coupling process. The sp3‐carbon‐halogen bonds can be activated through single electron transfer (SET) by the nickel catalyst in its low valence state, generated by cathodic reduction, and the generation of NiH species from alkyl halides is pivotal to this transformation. [ABSTRACT FROM AUTHOR]

This paper constructs a local classical solution of degenerate hyperbolic problem for the two‐dimensional nonlinear wave system. To deal with the parabolic degeneracy, we introduce a new set of coordinates to transform the nonlinear wave system to a new system that has explicitly singularity‐regularity structures. By constructing a weighted metric space, we establish the existence of solution for the new system. Returning the solution to the original variables, we obtain the existence of the classical solution for the nonlinear wave system with degenerate boundary value problem. [ABSTRACT FROM AUTHOR]

Two persistent and heavy haze episodes during the COVID‐19 lockdown (from 20 Jan to 22 Feb 2020) still occur in northern China, when anthropogenic emissions, particularly from transportation sources, are greatly reduced. To investigate the underlying cause, this study comprehensively uses in‐situ measurements for ambient surface pollutants, reanalysis meteorological data and the WRF‐Chem model to calculate the contribution of NOx emission change and weather‐climate change to the "unexpectedly heavy" haze. Results show that a substantial NOx reduction has slightly decreased PM2.5 concentration. By contrast, the weakest East Asian winter monsoon (EAWM) in the 2019–2020 winter relative to the past decade is particularly important for haze occurrence. A warmer and moister climate is also favorable. Model results suggest that climate anomalies lead to a 25–50 μg m−3 increase of PM2.5 concentration, and atmospheric transport is also an important contributor to two haze episodes. The first haze is closely related to the atmospheric transport of pollutants from NEC to the south, and fireworks emissions in NEC are a possible amplifying factor that warrants future studies. The second one is caused by the convergence of a southerly wind and a mountain wind, resulting in an intra‐regional transport within BTH, with a maximal PM2.5 increment of 50–100 μg m−3. These results suggest that climate change and regional transport are of great importance to haze occurrence in China, even with significant emission reductions of pollutants. Plain Language Summary: During the COVID‐19 lockdown (from 20 Jan to 22 Feb 2020), anthropogenic emissions, particularly from transportation sources, are significantly reduced. However, there are still two heavy haze pollution events occurred in northern China. Our modeling study constrained by measurements show that the substantial NOx reduction only leads to a slight decrease in PM2.5 concentration. In contrast, the weakest East Asian winter monsoon in the 2019–2020 winter relative to the past decade is very important for the haze occurrence. Climate anomalies contribute 25–50 μg m−3 to the PM2.5 concentration. Atmospheric transport such as the transport of pollutants from Northeast China to the south and the intra‐regional transport within the Beijing‐Tianjin‐Hebei, also plays an important role in the haze formation. The results suggest that weather‐climate anomalies and regional transport can significantly worsen air quality during the COVID‐19 lockdown in northern China, in spite of significant reductions in air pollutants and precursors. Key Points: Emission reduction and two heavy haze episodes simultaneously occur in northern China during the COVID‐19 lockdownAnomalously warm and moist climate with a weak East Asian Winter Monsoon, and regional atmospheric transport contribute to COVID‐19 hazeA substantial reduction of NOx emission slightly mitigates haze during the lockdown period [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID‐19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). In China, the Acacia catechu (AC)‐Scutellariae Radix (SR) formula has been widely used for pulmonary infection in clinical practice for several centuries. However, the potential role and mechanisms of this formula against COVID‐19 remains unclear. The present study was designed to dissect the active ingredients, molecular targets, and the therapeutic mechanisms of AC‐SR formula in the treatment of COVID‐19 based on a systems pharmacology strategy integrated by ADME screening, target prediction, network analysis, GO and KEGG enrichment analysis, molecular docking, and molecular dynamic (MD) simulations. Finally, Quercetin, Fisetin(1‐), kaempferol, Wogonin, Beta‐sitosterol, Baicalein, Skullcapflavone II, Stigmasterol were primarily screened to be the potentially effective active ingredients against COVID‐19. The hub‐proteins were TP53, JUN, ESR1, MAPK1, Akt1, HSP90AA1, TNF, IL‐6, SRC, and RELA. The potential mechanisms of AC‐SR formula in the treatment of COVID‐19 were the TNF signaling pathway, PI3K‐Akt signaling pathway and IL‐17 signaling pathway, etc. Furthermore, virtual docking revealed that baicalein, (+)‐catechin and fisetin(1‐) exhibited high affinity to SARS‐CoV‐2 3CLpro, which has validated by the FRET‐based enzymatic inhibitory assays with the IC50 of 11.3, 23.8, and 44.1 μM, respectively. And also, a concentration‐dependent inhibition of baicalein, quercetin and (+)‐catechin against SARS‐CoV‐2 ACE2 was observed with the IC50 of 138.2, 141.3, and 348.4 μM, respectively. These findings suggested AC‐SR formula exerted therapeutic effects involving "multi‐compounds and multi‐targets." It might be working through directly inhibiting the virus, improving immune function, and reducing the inflammatory in response to anti‐COVID‐19. Ultimately, this study would provide new perspective for discovering potential drugs and mechanisms against COVID‐19. [ABSTRACT FROM AUTHOR]

In this study, we build a multi‐station phase‐picking model named EdgePhase by integrating an Edge Convolutional module with a state‐of‐the‐art single‐station phase‐picking model, EQTransformer. The Edge Convolutional module, a variant of Graph Neural Network, exchanges information relevant to seismic phases between neighboring stations. In EdgePhase, seismograms are first encoded into the latent representations, then converted into enhanced representations by the Edge Convolutional module, and finally decoded into the P‐ and S‐phase probabilities. Compared to the standard EQTransformer, EdgePhase increases the precision (fraction of phase identifications that are real) and recall (fraction of phase arrivals that are identified) rate by 5% on our training and test data sets of Southern California earthquakes. To evaluate its performance in regions of different tectonic settings, we applied EdgePhase to detect the early aftershocks following the 2020 M7.0 Samos, Greece earthquake. Compared to a local earthquake catalog, EdgePhase produced 190% additional detections with an event distribution more conformative to a planar fault interface, suggesting higher fidelity in event locations. This case study indicates that EdgePhase provides a strong regional generalization capability in real‐world applications. Plain Language Summary: Identifying seismic phases from continuous waveforms is an important task for earthquake monitoring and early warning systems. Traditional phase recognition methods include visual inspection and detections based on mathematical functions (e.g., STA/LTA, kurtosis, AIC). Recently, machine learning technology has been applied to this task because of its fast operation speed and complete automation. A variety of neural‐network‐based models take the waveforms of a single station as input and predict the P‐phases and S‐phases. In this study, we improve the model performance by taking into account the mutually consistent features in multiple stations. We incorporate a Graph Neural Network module to exchange information relevant to seismic phases between neighboring stations. Compared to the standard single station model, our multi‐station model performs better on seismic data in Southern California in terms of the precision and recall rate. We also tested our model on the 2020 M7.0 Greece, Samos Earthquake and found that it detected significantly more aftershocks compared to local catalogs in the first month after the mainshock. Key Points: We developed EdgePhase, a multi‐station phase‐picking model, by fine‐tuning EQTransformer with Graphic Neural NetworksCompared to the standard EQTransformer, EdgePhase increases the F1 score by 5% on the Southern California Seismic data setPerformance evaluation of EdgePhase shows its strong generalization ability in real‐world applications [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is an abundant, inexpensive, renewable C1 resource and the main component of greenhouse gas, thereby the research for its sustainable and efficient conversion has received notable attention in recent years. Electrochemical organic synthesis, as a green and efficient synthetic method, is convinced to be an ideal approach for CO2 utilization. In this review, recent advances in electrocarboxylation with CO2 were summarized through different reaction types, which would disclose the great potential of electrocarboxylation in green organic synthesis. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is an abundant, inexpensive, renewable C1 resource and the main component of greenhouse gas, thereby the research for its sustainable and efficient conversion has received notable attention in recent years. Electrochemical organic synthesis, as a green and efficient synthetic method, is convinced to be an ideal approach for CO2 utilization. In this review, recent advances in electrocarboxylation with CO2 were summarized through different reaction types, which would disclose the great potential of electrocarboxylation in green organic synthesis. [ABSTRACT FROM AUTHOR]

Determination of the orientation of microfibrils within ultra-high molecular weight polyethylene (UHMWPE) fibers is considered to be an important method in evaluating the mechanical properties of the fibers. Four commonly used orientation evaluation methods are summarized and used to evaluate UHMWPE fibers at different drawing stages in the industrial line, and the results exhibit certain limitations. To overcome these limitations, a new evaluation method for quantitive characterization of UHMWPE fiber properties is proposed. Meanwhile, in situ small-angle X-ray scattering data of an UHMWPE fiber drawn at 100 °C were used to perform a Pearson correlation coefficient test, and the results show a very strong correlation between the strain ratio and the evaluated coefficient. [ABSTRACT FROM AUTHOR]

Identifying the sources of atmospheric Carbon dioxide (CO2) is an important prerequisite for developing effective mitigation strategies. Here we conducted regular observations of the atmospheric CO2 mixing ratio and its carbon isotope compositions (i.e., Δ14C and δ13C) in Xi'an and Beijing during winter, to estimate source contributions of CO2 emissions in Chinese megacities. The results showed that CO2 emissions in both Xi'an and Beijing originated mainly from fossil‐fuel sources, which contributed 65 ± 3% and 82 ± 2% of the total CO2 enhancement, respectively, during the sampling period; the results also revealed a substantial biogenic CO2 contribution during winter. We further separated the fossil‐fuel sources into contributions from coal, oil and natural gas combustions. We found that coal combustion was the dominant anthropogenic source in Xi'an, accounting for 54 ± 4% of the total fossil‐fuel emissions, and oil and natural gas contribute almost equally to the emissions. In contrast, emission from natural‐gas combustion was the main fossil‐fuel source in Beijing, accounting for more than half of the total fossil‐fuel emissions, whereas, coal combustion contributed only 17 ± 10%. These top‐down results are generally consistent with emission inventory when seasonal variations of emissions are considered; some differences between the two methods indicated that the inventory for Xi'an might be underestimating the emissions from oil consumption. This pilot study confirms the potential of direct verification between top‐down and bottom‐up methods from the perspective of source attribution. Plain Language Summary: Quantifying Carbon dioxide (CO2) sources from cities is crucial for formulating policies and evaluating targets because cities have become the key region and basic unit for regulating emissions. Here, we take Xi'an and Beijing, two Chinese megacities, as the study case to conduct source attribution of atmospheric CO2 based on the powerful tracer ability of dual carbon isotopes (14C and 13C). We estimated the emission contributions of fossil source CO2 (CO2ff) and the fractions of different fossil fuels in CO2ff. We also performed independent evaluation for emission inventory data by the direct comparisons between the fractions of different fossil fuels obtained from "top‐down" and "bottom‐up" methods. This study can provide a new perspective for the verification of urban carbon emission data, and is of great significance to further improve the reliability of carbon budgets for Chinese cities. Key Points: The Carbon dioxide (CO2) emission patterns regarding the source contributions are completely different between Beijing and Xi'anBiogenic CO2 is also an important source for megacities and need to be considered in urban carbon budgetsWe confirm the potential of direct verification between top‐down and bottom‐up methods from a new perspective [ABSTRACT FROM AUTHOR]

Herein, we disclose a straightforward, robust, and simple route to access β‐substituted desaturated cyclic amines via an electrochemically driven desaturative β‐functionalization of cyclic amines. This transformation is based on multiple single‐electron oxidation processes using catalytic amounts of ferrocene. The reaction proceeds in the absence of stoichiometric amounts of electrolyte under mild conditions, affording the desired products with high chemo‐ and regioselectivity. The reaction was tolerant of a broad range of substrates and also enables late‐stage β‐C(sp3)−H acylation of potentially valuable products. Preliminary mechanistic studies using cyclic voltammetry reveal the key role of ferrocene as a redox mediator in the reaction. [ABSTRACT FROM AUTHOR]

This phase 1, 2‐part, 2‐period, open‐label, drug‐drug interaction study evaluated the potential for pharmacokinetic interactions between upadacitinib and rosuvastatin, an organic anion transporting polypeptide (OATP) 1B1 and breast cancer resistance protein substrate, or atorvastatin, a cytochrome P450 3A, OATP1B1, and OATP1B3 substrate, in 36 healthy volunteers. During period 1, a single dose of rosuvastatin (5 mg; part 1) or atorvastatin (10 mg; part 2) was administered on day 1, followed by a washout period of 5 days. During period 2, once‐daily doses of upadacitinib extended‐release (30 mg) were administered on days 1 to 10, and a single dose of rosuvastatin (5 mg; part 1) or atorvastatin (10 mg; part 2) was administered 1 hour after the upadacitinib dose on day 7. Serial blood samples were collected for assays of drug concentrations. In Part 1, rosuvastatin maximum observed plasma concentration (Cmax) and area under the plasma concentration–time curve from time 0 to infinity (AUCinf) were 23% and 33% lower, respectively, when administered with upadacitinib relative to when administered alone. In part 2, atorvastatin Cmax and AUCinf was 11% and 23% lower, respectively, when administered with upadacitinib relative to when administered alone. The Cmax and AUCinf of the active metabolite ortho‐hydroxyatorvastatin remained unchanged. Administration of a single 5‐mg dose of rosuvastatin or a single 10‐mg dose of atorvastatin had no relevant effect on upadacitinib Cmax or area under the plasma concentration–time curve. These results demonstrated that upadacitinib has no clinically relevant effect on the pharmacokinetics of rosuvastatin and atorvastatin or on substrates transported by OATP1B or breast cancer resistance protein. [ABSTRACT FROM AUTHOR]

Recently, the microwave‐assisted heating method has become a commonly used and environmentally friendly heating technology in the field of organic and polymeric synthetic chemistry. A series of poly(5,5‐dimethyl trimethylenecarbonate‐co‐2‐phenyl‐5,5‐bis[oxymethyl] trimethylenecarbonate) (P[DTC‐co‐PTC]) were synthesized by microwave‐assisted ring‐opening polymerization of 5,5‐dimethyl trimethylene carbonate (DTC) and 2‐phenyl‐5,5‐bis(oxymethyl) trimethylene carbonate (PTC) using tin(II) 2‐ethylhexanoate and aluminum isopropoxidase, the catalysts. These co‐polycarbonates were further reduced by a palladium‐carbon catalyst (Pd/C catalyst, 10%) to make partly deprotected polycarbonates (HPDPC). These two co‐polycarbonates were characterized by gel permeation chromatography, 1HNMR, Fourier transform infrared spectroscopy, UV, differential scanning calorimetry, and automatic contact‐angle measurements. The influences of the microwave irradiation time, microwave power, monomer feed molar ratio, different catalysts, and monomer/catalyst feed molar ratio on the molecular weights of co‐polycarbonates were also investigated. In vitro water absorption, degradation and drug release tests indicated that partly deprotected co‐polycarbonate HPDPC possessed greater hydrophilicity, faster degradation rate, and faster drug release rate than that of corresponding P(DTC‐co‐PTC). Therefore, microwave‐assisted polymerization is a clean and cheap heating method and can be used for ring‐opening copolymerization of carbonates, which enhances the hydrophilicity and biodegradation rate of aliphatic polycarbonates. [ABSTRACT FROM AUTHOR]

A variety of climatological indices have been established to illustrate the impact of climate change on air pollution in China, but major facts for causing variations of air pollution attributed to climate change are still unclear. Here, using in‐situ PM2.5 (particles with the aerodynamic diameter less than 2.5 μm) measurement, atmospheric reanalysis data and a chemical transport model, we show that meridional distribution of PM2.5 loadings is strongly modulated by the intensity of East Asian winter monsoon (EAWM). The EAWM drives the heavily polluted zone in eastern China to migrate southward, i.e., under stronger EAWM, more southward migration of air pollution occurs. We expect that the migration will likely re‐distribute carbon sources‐ and sinks‐related ecosystem, posing a new challenge for the Chinese government, who needs to implement region‐different emission reduction plans in the future, to mitigate air pollution and to go carbon neutral. Plain Language Summary: The relationship between the severe air pollution in China and climate has drawn much attention from scientific community, which still remains unclear. In this study, we present that air pollution with high PM2.5 loadings in winter, China is significantly modulated by East Asian winter monsoon (EAWM) based on ambient PM2.5 measurements, atmospheric reanalysis data and the GEOS‐Chem model. We find that the change in EAWM intensity dominates the location of heavily polluted zone and its meridional distribution. Stronger EAWM generally drives the zone to migrate more southward in eastern China, highlighting the predominant role of EAWM in redistributing air pollution of China during wintertime. Under climate change, the inter‐annual variability and decadal oscillation of EAWM projected by CMIP5 and CMIP6 models indicate a southward migration of the heavily polluted zone in next decades, probably approaching the Yangtze River Delta. This result may pose new challenges in air pollution control for local governments in different regions regarding climatic influence. Key Points: East Asian winter monsoon strongly modulates PM2.5 levels meridionally in eastern ChinaUnder climate change, the heavily polluted zone will likely move southward to Yangtze River Delta in the next decadesChina needs to implement regional‐different emission reduction measures regarding to the influence of climate change [ABSTRACT FROM AUTHOR]

The atmospheric oxidizing capacity (AOC) plays a key role in atmospheric chemistry, determining the removal of most reduced gases in the atmosphere. In this study, we assess the summertime AOC from 7 to 22 June 2014 associated with a field campaign conducted at Wangdu in the Beijing‐Tianjin‐Hebei region (BTH), China using the WRF‐Chem model. The model reasonably well reproduces the incident solar radiation, ambient O3 and fine particulate matter (PM2.5) concentrations, the photolysis rates of O3 and NO2, and radical concentrations against measurements in the BTH. The model results show high daytime AOC levels in urban areas and relatively low AOC in remote areas of the BTH. The diurnal cycle of the AOC exhibits a unimodal pattern with peaks at noon. OH radical contributes about 68% of the daily average AOC in Beijing, followed by O3 (27%) and NO3 (5%). At Wangdu, the production rate of OH radical reaches around 13 ppb h−1 at noon, which is mainly resulted from the reaction of HO2 with NO. The OH radical loss is primarily contributed by reactions with volatile organic compounds, followed by CO and NO2. Statistically, the population hourly or afternoon average O3 and Ox (=O3 + NO2) concentrations are significantly correlated with the AOC in Beijing, constituting potential simplified tracers to indicate the AOC level. Key Points: The summertime atmospheric oxidizing capacity (AOC) over the Beijing‐Tianjin‐Hebei area is assessed combining a field campaign and WRF‐Chem simulationOH radical contributes about 68% of the daily average AOC in Beijing, followed by O3 (27%) and NO3 (5%)Population hourly or afternoon average O3 and Ox (=O3 + NO2) concentrations constitute potential simplified tracers for the AOC level [ABSTRACT FROM AUTHOR]

A series of new alkali-metal-based coordination polymers, [Li(H2IMDC)(H2O)]n (1), [Na2(H2IMDC)2(H3IMDC)2(H2O)4]n (2), and [K(H2IMDC)(H2O)]n (3), have been constructed under solvothermal conditions by using imidazole-4,5-dicarboxylic acid (H3IMDC) as ligand. The structure of the complexes has been determined by single-crystal X-ray diffraction and further characterized by elemental analyses, IR spectra, powder X-ray diffraction and thermogravimetric analyses. The single crystal Xray structural studies showed that their structural dimensionalities varying from 1-D zigzag chain, 2-D 44-sql network to 3-D 4,6-connected coordination framework are strongly governed by the ionic radii and coordination geometries of the metal cations. For the first time, the alkali-metal-based coordination polymers were demonstrated to be effective catalysts for the solvent-free ring-opening polymerization (ROP) of ɛ-caprolactone. The catalytic activity of complexes 1–3 depends on the metal cations, increasing in the order Li+ < Na+ < K+. [ABSTRACT FROM AUTHOR]

The input‐output finite‐time stability and stabilization of a class of fractional‐order switched singular continuous‐time systems with order 0<α<1 are studied in this paper. First, based on the average dwell time switching technique, by constructing multiple Lyapunov functions, the sufficient conditions of input‐output finite‐time stability for the considered systems are derived in the form of linear matrix inequalities (LMIs). Second, a suitable LMI‐based state feedback controller is designed. Finally, an illustrative example is presented to show the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

This phase 1 study characterized the effect of multiple doses of upadacitinib, an oral Janus kinase 1 selective inhibitor, on the pharmacokinetics of the cytochrome P450 (CYP) 2B6 substrate bupropion. Healthy subjects (n = 22) received a single oral dose of bupropion 150 mg alone (study period 1) and on day 12 of a 16‐day regimen of upadacitinib 30 mg once daily (study period 2). Serial blood samples for measurement of bupropion and hydroxybupropion plasma concentrations were collected in each study period. The central values (90% confidence intervals) for the ratios of change were 0.87 (0.79‐0.96) for bupropion maximum plasma concentration (Cmax), 0.92 (0.87‐0.98) for bupropion area under the plasma‐concentration time curve from time 0 to infinity (AUCinf), 0.78 (0.72‐0.85) for hydroxybupropion Cmax, and 0.72 (0.67‐0.78) for hydroxybupropion AUCinf when administered with, relative to when administered without, upadacitinib. After multiple‐dose administration of upadacitinib 30 mg once daily, upadacitinib mean ± SD AUC0‐24 was 641 ± 177 ng·h/mL, and Cmax was 83.3 ± 30.7 ng/mL. These results confirm that upadacitinib has no relevant effect on pharmacokinetics of substrates metabolized by CYP2B6. [ABSTRACT FROM AUTHOR]

The tropical Pacific plays an important role in the global carbon cycle. However, little is known on the large-scale variability of particulate organic carbon (POC) and the contribution of phytoplankton carbon (PhyC) in this region. Here, we used a basin-scale model to study the spatiotemporal variability of POC and PhyC contribution over 1981–2016 in the tropical Pacific. The model reproduces the spatial and temporal variability of the observed POC in this region. Both satellite and modeled POC show a clear west-to-east increase (from 40 to 60 mg m−3) in the equatorial Pacific. The contribution of PhyC to POC is greater in the iron-limited eastern region (∼30%) than in the nitrogen-limited western region (∼20%). There are strong interannual variabilities in both POC and the contribution of PhyC to POC, which are largely associated with the El Niño–Southern Oscillation (ENSO) events. POC stock and downward flux show significant increases (10%–20%) in the frontal region (near the dateline) but smaller changes in the eastern equatorial Pacific post-1998, due to the Pacific Decadal Oscillation (PDO) regime shift. There were significant increases (∼5–10% to the west and ∼5% to the east) in the transfer efficiency of POC across the basin during 1999–2014 due to the PDO regime shift. This study highlights the impacts of iron and nitrogen co-limitations on phytoplankton dynamics and physical forcing on the carbon cycle of the tropical Pacific, with implications for the global carbon cycle. [ABSTRACT FROM AUTHOR]

Boar sperm are susceptible to oxidative damage caused by reactive oxygen species (ROS) during storage. Adenosine monophosphate (AMP)‐activated protein kinase (AMPK) is an important therapeutic target, because it is a cellular metabolism energy sensor and key signalling kinase in spermatozoa. We evaluated the effects of rosmarinic acid (RA), an antioxidant, on boar sperm during liquid storage to determine whether it protects boar sperm via AMPK activation. Boar ejaculates were diluted with Modena extender with different concentrations of RA and stored at 17°C for 9 days. Sperm quality parameters, antioxidant capacity, energy metabolism, AMPK phosphorylation and fertility were analysed. Compared with the control, 40 μmol/L significantly improved sperm motility, plasma membrane integrity and acrosome integrity (p <.05). The effective storage time of boar sperm was up to 9 days. On the third and seventh days, the sperm with RA exhibited increased total antioxidant capacity (T‐AOC), superoxide dismutase (SOD) activity, adenosine triphosphate (ATP) content, mitochondrial membrane potential (ΔΨm) and glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) activity, whereas malondialdehyde (MDA) content was significantly decreased (p <.05). Western blot showed that RA, as well as AICAR (AMPK activator), promoted AMPK phosphorylation, whereas Compound C (AMPK inhibitor) inhibited this effect. The sperm–zona pellucida binding experiment showed that 40 μmol/L RA increased the number of sperm attached to the zona pellucida (p <.05). These findings suggest meaningful methods for improved preservation of boar sperm in vitro and provide new insights into the mechanism by which RA protects sperm cells from oxidative damage via AMPK activation. [ABSTRACT FROM AUTHOR]

In this study, the Dynamical‐Statistical‐Analog Ensemble Forecast model for landfall typhoon precipitation (the DSAEF_LTP model), which has been developed by Ren et al., in 2020, is applied to precipitation simulations for super‐typhoon Lekima (2019), a tropical cyclone (TC) that produced heavy rainfall over eastern China. A new variable, TC intensity, is introduced into the generalized initial value (GIV) of the DSAEF_LTP model. Two different groups of simulation experiments, one group including the new TC intensity variable in the GIV and the other group excluding it, have been conducted. Results show that, with TC intensity, the ability of the DSAEF_LTP model to forecast heavy rainfall (i.e. accumulated precipitation exceeding thresholds of 250 and 100 mm) for Lekima is improved. Its threat score (TS) ranks the second compared with that of three numerical weather prediction models (i.e. ECMWF, GRAPES and GFS). Further study shows that three factors prevent the DSAEF_LTP model from achieving more satisfactory results for Lekima: the historically rare occurrence of extreme precipitation in northern China during Lekima, the increase of forecast track error when Lekima moved northwards, and the calculation of similarity between tracks of Lekima and historical TCs within an improper region (i.e. similarity region). To solve the third problem, new similarity region schemes are adopted that produce higher TS, in which case TS of precipitation greater than 100 mm (TS100) ranks first and TS of precipitation greater than 250 mm (TS250) gets closer to the first place. [ABSTRACT FROM AUTHOR]

An important manifestation of the background or coseismic deformation surrounding megathrust earthquakes is the offshore microseismicity, which are difficult to be directly detected by land‐based seismic instruments. Here, we improve the capability of detecting offshore events by combining two popular techniques: backprojection (BP) imaging and matched‐filter (MF) detection. The BP method is effective in retrieving offshore seismicity (Mw > 4.5) buried in the coda wave of large earthquakes. The capability of the MF method depends on the availability of the template pool; therefore, the BP‐inferred events can be used as additional templates to expand the MF detections (BP‐MF). We performed the BP‐MF approach in the period within 600 days after the 2011 Mw 9.0 Tohoku earthquake. We find overall 44.2% more offshore events than those listed in the Japan Meteorological Agency (JMA) catalog. In the near‐trench area, we detect 213% more events. Among the newly detected Mw > 4 events, the BP template contributions are twice more than those matched by the JMA templates. Based on the spatial consistency between aftershock‐depleted zones and large coseismic slip, we identify a possible large coseismic slip zone in the near‐trench region offshore Fukushima. Large b values (≥1.2) are found close to large aftershocks, possibly indicating localized pockets of small differential stresses. At several locations close to the trench, p values (0.93–1.11) are higher than those in the inland area (0.64–0.85). This may be due to the larger coseismic slip and hence larger stress drop of the outer‐rise normal‐faulting events compared to the deeper thrust‐faulting events. Key Points: We improve the capability of detecting offshore events by combining backprojection imaging and matched‐filter detection (BP‐MF)The BP‐MF approach detects twice more events in the near‐trench region than those of the JMA catalogWe identify a possible large‐slip zone in the near‐trench region offshore Fukushima based on aftershock‐depleted zones [ABSTRACT FROM AUTHOR]

As a high‐efficient photocatalyst, g‐C3N4/TiO2 (PCN) was successfully prepared by thermal polymerization. In addition, the structure and morphological characteristics of the as‐prepared samples were investigated by XRD, BET, XPS, SEM, TEM, and UV‐vis DRS. The results revealed that in the presence of g‐C3N4, the physicochemical properties of the catalyst and the band gap of PCN decreased from 3.09 eV to 2.98 eV, clearly indicative of the enhanced photocatalytic performance relative to pure P25 or g‐C3N4 under sunlight. Furthermore, the photocatalytic properties of PCN were examined by the degradation of pyridine and other nitrogen heterocyclic pollutants under sunlight irradiation. Next, the main factors affecting the photocatalytic activity were investigated in detail, including the initial concentration of the pollutant, the mass of the photocatalyst, the initial pH of the solution, and the doping amount of g‐C3N4, as well as different free‐radical scavengers. On the other hand, the reusability of PCN demonstrated that photocatalysts exhibit outstanding photocatalytic stability after 10 cycles. Hence, high efficiency photocatalysts demonstrate potential for industrial applications such as sewage treatment. [ABSTRACT FROM AUTHOR]

GSTP1 has been considered to be a marker for malignancy in many tissues. However, the existing GST fluorescent probes are unfavorable for in vivo imaging because of the limited emission wavelength or insufficient fluorescence enhancement (six‐fold). The limited fluorescence enhancement of GST fluorescent probes is mainly ascribed to the high background signals resulting from the spontaneous reaction between GSH and the probes. In this work, a highly specific GST probe with NIR emission has been successfully developed through optimization of the essential unit of the probe to repress the spontaneous reaction. The novel GST probe exhibits over 100‐fold fluorescence enhancement upon incubation with GSTP1/GSH and high selectivity over other potential interference. In addition, the probe has been proved to be capable of tracking endogenous GST in A549 cells. Finally, the in vivo imaging results demonstrate that the probe can be used for effective imaging of endogenous GST activity in subcutaneous tumor mouse with high contrast. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the effects of upadacitinib, a Janus kinase 1 inhibitor, on in vivo activity of different cytochrome P450 (CYP) enzymes using a cocktail approach. Healthy subjects (n = 20) received single oral doses of the modified Cooperstown 5+1 cocktail drugs (midazolam [CYP3A], caffeine [CYP1A2], warfarin + vitamin K [CYP2C9], omeprazole [CYP2C19], and dextromethorphan [CYP2D6]) without upadacitinib and on day 11 (midazolam) or 12 (all other probes) of a 15‐day regimen of upadacitinib 30 mg once daily (extended‐release formulation). Serial blood samples and 12‐hour urine samples were collected for assays of the probe substrates and select metabolites. The ratio (90%CI) of area under the plasma concentration‐time curve from time 0 to infinity (AUCinf) central values when the cocktail drugs were administered with upadacitinib relative to when administered alone were 0.74 (0.68‐0.80) for midazolam, 1.22 (1.15‐1.29) for caffeine, 1.11 (1.07‐1.15) for S‐warfarin, 1.07 (0.95‐1.22) for dextromethorphan, and 0.82 (0.72‐0.94) for omeprazole. The ratio (90%CI) was 1.09 (1.00‐1.19) for 5‐hydroxy‐omeprazole to omeprazole AUCinf ratio and 1.17 (0.97‐1.41) for dextromethorphan to dextrorphan 12‐hour molar urinary ratio. Upadacitinib 30 mg once daily (a dose that is twice the optimal dose in rheumatoid arthritis based on phase 3 results) has a limited effect on CYP3A activity (26% decrease in exposure of midazolam, a sensitive CYP3A substrate) and no relevant effects on CYP1A2, CYP2C9, CYP2C19, or CYP2D6 activity in vivo. No clinically relevant changes in plasma exposures are expected for drugs that are substrates for the evaluated CYP enzymes when coadministered with upadacitinib. [ABSTRACT FROM AUTHOR]

Acacia catechu (L.f.) Willd (ACW) and Scutellaria baicalensis Georgi (SBG) are one of the most famous couplet Chinese medicines, widely used for treating infantile cough, phlegm, and fever caused by pulmonary infection. However, the underlying molecular mechanism of their anti-inflammatory activity has not been determined. The aim of this study was to evaluate the protective effect of this couplet Chinese medicines (ACW-SBG) on lipopolysaccharide (LPS)-induced inflammatory responses in acute lung injury (ALI) model of rats and the potential molecular mechanisms responsible for anti-inflammatory activities in alveolar epithelial type II cells (AEC-II). Standardization of the 70% ethanol extract of ACW and SBG was performed by using a validated reversed-phase high-pressure liquid chromatography method. Rats were pretreated with ACW-SBG for 7 days prior to LPS challenge. We assessed the effects of ACW-SBG on the LPS-induced production of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) in the bronchoalveolar lavage fluid (BALF). The wet-to-dry weight ratio was calculated, and hematoxylin and eosin staining of lung tissue was performed. Cell viability of AEC-II was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Real-time quantitative reverse transcription polymerase chain reaction assay was carried out to quantify the relative gene expression of TNF-α and IL-1β in AEC-II. The western blotting analysis was executed to elucidate the expression of mediators linked to nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and phosphatidylinositol-3 kinase-protein kinase B (PI3K-Akt) signaling pathways. ACW-SBG significantly decreased lung wet-to-dry weight ratio, ameliorated LPS-induced lung histopathological changes, and reduced the release of inflammatory mediators such as TNF-α and IL-1β in BALF. In AEC-II, we found that the expression of TNF-α mRNA was also inhibited by ACW-SBG. ACW-SBG blocked NF-κB activation by preventing the phosphorylation of NF-κB (p65) as well as the phosphorylation and degradation of the inhibitor of kappa B kinase. ACW-SBG extracts also inhibited the phosphorylation of respective MAPKs (c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38) as well as Akt. The present study demonstrated that ACW-SBG played a potent anti-inflammatory role in LPS-induced ALI in rats. The potential molecular mechanism was involved in attenuating the NF-κB, MAPKs, and PI3K-Akt signaling pathways in LPS-induced AEC-II. [ABSTRACT FROM AUTHOR]

Sulfanilamide (SA) is an effective broad‐spectrum antibacterial agent in human and veterinary medicine. The purpose of this study was to evaluate the effects of SA on boar sperm quality during liquid storage at 17°C and determine the optimal concentration of SA and its effects on bacterial growth, microbial composition, and maternal fertility. Boar ejaculates were diluted with a basic extender, containing different concentrations of SA, and stored in a 17°C incubator for 6 days. The sperm motility, plasma membrane integrity, and acrosome integrity were measured daily. The results showed that when the concentration of SA was 0.02 g/L, the sperm quality parameters were significantly higher than those of all other treatment groups (p < .05). We also monitored the bacterial growth and compared the differences in the microbial species between the 0.02 g/L SA group and the control by 16S rDNA sequencing. The results revealed that some bacteria, such as Staphylococcus and Pseudomonas, were considerably lower in the 0.02 g/L SA group than in the control group (p < .05). In addition, preserved semen was used for artificial insemination, and results showed that 0.02 g/L SA group had a higher litter size, and its pregnancy rate was 92.5%. [ABSTRACT FROM AUTHOR]

Upadacitinib is a selective Janus kinase 1 inhibitor being developed for the treatment of several inflammatory autoimmune diseases, including rheumatoid arthritis. Upadacitinib is a nonsensitive substrate for metabolism by cytochrome P450 3A enzymes. This open‐label, single‐dose, multicenter study assessed the pharmacokinetics of upadacitinib following oral administration of a single 15‐mg dose of the upadacitinib extended‐release formulation in subjects with mild (n = 6) and moderate (n = 6) hepatic impairment relative to demographically matched healthy subjects (n = 6). Subjects were assigned to 1 of the 3 groups according to the Child‐Pugh classification. Relative to subjects with normal hepatic function, the ratios (90% confidence intervals) of upadacitinib area under the plasma concentration‐versus‐time profile from time 0 to infinity (AUCinf) for subjects with mild and moderate hepatic impairment were 1.28 (0.91‐1.79) and 1.24 (0.87‐1.76), respectively. The central ratios of upadacitinib maximum observed concentration (Cmax) were 1.04 (0.77‐1.39) and 1.43 (1.05‐1.95) in subjects with mild and moderate hepatic impairment, respectively, compared with subjects with normal hepatic function. No clinically significant changes in vital signs or hematology measurements were observed, and no new safety events were identified in this study. These results indicate that mild and moderate hepatic impairment has no clinically relevant effect on upadacitinib pharmacokinetics. [ABSTRACT FROM AUTHOR]

Homogeneous hollow CuO-ZnO-Al2O3 microspheres, which were synthesised, used carbonaceous saccharide as a template by the hydrothermal treatment at 180°C. The hollow microspheres structure of composite metal oxides was characterised by the methods of X-ray powder diffraction, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption isothermal. In the evaluation of the hydrogenation of carbon dioxide, the synthesised hollow CuO/ZnO/Al2O3 composite microspheres exhibited higher selectivity and yield of methanol than CuO/ZnO/Al2O3 prepared by a co-precipitation method. An optimum yield of methanol of 15.3% with the 24.7% CO2 per pass conversion was obtained under the reaction conditions of pressure at 3.0 MPa, space velocity at 1800 ml gcat -1 h-1, the volume ratio of CO2/H2 at 1:3 and temperature at 262°C. [ABSTRACT FROM AUTHOR]

In this study, we translated and localized the Adult Decision‐making Competence scale (A‐DMC) and tested its reliability and validity with large samples. Results show the Chinese A‐DMC has relatively good reliability (Cronbach's alpha above 0.6 and test–retest reliability coefficients ranging from 0.44 to 0.78 on all subscales), comparable with the original version. Regarding validity, results of exploratory factor analysis and confirmatory factor analysis support the one‐factor model, indicating the A‐DMC has good internal consistency and construct validity. A‐DMC scores correlated positively with cognitive ability, constructive decision‐making styles, and good decision outcomes. Additionally, individuals with higher A‐DMC scores were found to perform better on the Cambridge gambling task and Iowa gambling task. These results confirm the validity of the Chinese version of the A‐DMC, which is suitable for measuring decision‐making competence in Chinese adults. [ABSTRACT FROM AUTHOR]

Adding a certain amount of antioxidants to semen extender has been shown to improve semen quality. The aim of present study was to elucidate whether the supplementation of melatonin to the Tris‐based extender (CTR) could enhance the quality of ram spermatozoa during storage at 4°C. Ram semen samples were collected and diluted with CTR extender containing different concentrations (0, 0.05 (M 0.05), 0.1 (M 0.1), 0.2 (M 0.2) or 0.4 (M 0.4) mM) of melatonin. Sperm routine indicators, mitochondrial activity, total antioxidant capacity (T‐AOC) and malondialdehyde (MDA) content were analysed in control and melatonin treatment groups. The higher per cent of motility, plasma membrane integrity, mitochondrial activity and T‐AOC activity was observed in M 0.05, M 0.1 and M 0.2 groups compared to control group at 5 days of storage (p < 0.05), while lower percentage of MDA content was observed among these groups (p < 0.05). In addition, there were no significant differences in acrosome integrity among the control and M 0.05, M 0.1 and M 0.2 groups during the experiment. The above results show that the addition of 0.05, 0.1, 0.2 mM of melatonin is beneficial to the preservation of ram semen during liquid storage at 4°C mainly through antioxidative stress. [ABSTRACT FROM AUTHOR]

Upadacitinib is a novel selective Janus kinase 1 inhibitor developed for treatment of rheumatoid arthritis and other autoimmune diseases. The objective of this study was to assess the pharmacokinetics and safety of a single upadacitinib dose in subjects with normal renal function and in subjects with renal impairment. A total of 24 subjects between the ages of 18 and 75 years were assigned to 1 of 4 renal function groups based on estimated glomerular filtration rate (normal, mild, moderate, severe; N = 6/group). A single 15‐mg dose of upadacitinib extended‐release formulation was administered under fasting conditions. Serial plasma and urine samples were assayed to evaluate the effect of renal impairment on upadacitinib exposure through regression analysis and analysis of covariance. The primary analysis was the regression analysis of upadacitinib exposures versus estimated glomerular filtration rate. The point estimates for upadacitinib plasma exposure ratios (90% confidence interval [CI]) in subjects with mild, moderate, and severe renal impairment were 1.18 (90%CI, 1.06–1.32), 1.33 (90%CI, 1.11–1.59), and 1.44 (90%CI, 1.14–1.82) for area under the plasma concentration–time curve and 1.06 (90%CI, 0.92–1.23), 1.11 (90%CI, 0.88–1.40), and 1.14 (90%CI, 0.84–1.56) for maximum observed plasma concentration, respectively, relative to subjects with normal renal function based on the regression analysis. The analysis of covariance categorical analysis provided consistent results. Upadacitinib was well tolerated by all subjects, and no safety issues were identified in subjects with renal impairment. Renal impairment has a limited effect on upadacitinib pharmacokinetics. This is in agreement with the known limited role of urinary excretion in upadacitinib elimination. Based on the limited impact on exposure, no dose adjustment is necessary for upadacitinib in subjects with impaired renal function. [ABSTRACT FROM AUTHOR]

Upadacitinib is a novel selective oral Janus kinase 1 (JAK) inhibitor being developed for treatment of several inflammatory diseases. Oral contraceptives are anticipated to be a common concomitant medication in the target patient populations. This study was designed to evaluate the effect of multiple doses of upadacitinib on the pharmacokinetics of ethinylestradiol and levonorgestrel in healthy female subjects. This phase I, single‐center, open‐label, 2‐period crossover study evaluated the effect of multiple doses of 30 mg once daily extended‐release upadacitinib on the pharmacokinetics of a single oral dose of ethinylestradiol/levonorgestrel (0.03/0.15 mg; administered alone in period 1 and on day 12 of a 14‐day regimen of upadacitinib in period 2) in 22 healthy female subjects. The ratios (90% confidence intervals) for maximum plasma concentration and area under the plasma drug concentration–time curve from time zero to infinity following administration of ethinylestradiol/levonorgestrel with upadacitinib compared with administration of ethinylestradiol/ levonorgestrel alone were 0.96 (0.89–1.02) and 1.1 (1.04–1.19), respectively, for ethinylestradiol, and 0.96 (0.87–1.06) and 0.96 (0.85–1.07), respectively, for levonorgestrel. The harmonic mean terminal half‐life for ethinylestradiol (7.7 vs 7.0 hours) and levonorgestrel (37.1 vs 33.1 hours) was similar in the presence and absence of upadacitinib. Ethinylestradiol and levonorgestrel were bioequivalent in the presence and absence of upadacitinib. Therefore, upadacitinib can be administered concomitantly with oral contraceptives containing ethinylestradiol or levonorgestrel. [ABSTRACT FROM AUTHOR]

A novel synthesis of cyclobutanol‐fused 2‐nitronaphthalen‐1‐ols and nitrocyclobutane‐fused naphthalene‐1,2‐diones through cascade reactions of benzene‐linked allenynes with tert‐butyl nitrite is presented. The formation of the title compounds involves a tandem process including allenyne [2+2] cycloaddition, radical addition onto the in situ formed cyclobutenyl moiety followed by radical coupling/oxidation. Interestingly, different kinds of functionalized naphthalene derivatives could be obtained selectively from the same substrates, and the selectivity was easily controlled by finely tuning the reaction conditions. [ABSTRACT FROM AUTHOR]

The roles of anthropogenic emissions and weather conditions in air pollution over eastern China have been widely discussed but still controversial. Here we focus on the impact of the intraseasonal variability of midtropospheric weather circulations on air quality during 2015–2016 winter. We use the European Center for Medium‐Range Weather Forecasts reanalysis data to calculate westerly wind index (WI) and meridionality in the midtroposphere and also calculate the intensity of Siberian High at the surface. The results suggest that there were lower WI, higher meridionality, and strengthened Siberian High in January 2016 compared with the conditions in December 2015. Lower WI and higher meridionality imply for wavier midtropospheric weather circulations and stronger surface northerly winds, thereby causing more southward cold fresh air advection and resulting in the lower PM2.5 concentrations over eastern China in January 2016. Sensitivity experiments conducted by the Weather Research and Forecasting Chemical model show that the intraseasonal weather variability dominantly causes lower PM2.5 concentrations in January 2016. It not only counteracts increments in PM2.5 concentrations induced by the increased emission but also reduces PM2.5 concentrations by an extra 25–100 μg/m3. We also simulate two extreme weather patterns and compare their effects on PM2.5 concentrations. Difference in these two weather patterns induces changes in PM2.5 concentrations by 50–200 μg/m3 over eastern China and the maximal change exceeding 200 μg/m3. These findings suggest that understanding the variability of the dominant midtropospheric circulation is the key to successfully forecasting short‐term air quality over eastern China in winter. Plain Language Summary: The subseasonal variation of PM2.5 concentrations is dominantly induced by the intraseasonal variability of weather circulations during 2015–2016 winter. In the early winter (December 2015), a straight westerly wind prevails at the midtroposphere, confining cold air within the high latitudes and causing the accumulation of PM2.5 concentrations in eastern China, while in the late winter (January 2016), a north‐to‐south oriented airflow at the midtroposphere allows cold air advection to eastern China, reducing PM2.5 concentrations. Consequently, the intraseasonal weather variability leads to the maximal reduction of PM2.5 concentrations by 50–200 μg/m3. These findings suggest that understanding the variability of the midtroposphere circulation patterns is the key to successfully forecasting and improving air quality in winter. Key Points: Monthly emission change in 2015‐2016 winter results in an increment in PM2.5 concentrations by 10‐50 micrograms per cubic meter in eastern ChinaWeather variability not only offsets PM2.5 increments due to emission change but also reduces PM2.5 concentrations by an extra 25‐100 micrograms per meterMidtropospheric westerly wind circulations are the key to understanding subseasonal variations of PM2.5 concentrations [ABSTRACT FROM AUTHOR]

Abstract: China has suffered severe air pollutions during wintertime as national industrialization and urbanization have been increasingly developed in the past decades. Recent studies suggest that climate change has important impacts on extreme haze events in northern China. This study uses reanalysis datasets to analyze the trend and variability of Siberian High (SiH) intensity, and its relationship with the Arctic temperature and sea ice cover (SIC) in past two decades. The results show that Arctic is warming accompanied by a rapid decline of SIC, while Eurasia is cooling and SiH intensity is gradually enhancing. The statistics illustrates that the SiH has a significantly positive correlation to the temperature (R = 0.70), and a significant anticorrelation to the SIC (R = −0.69), and this is because the warming Arctic and the reducing SIC enhanced the SiH. The enhanced SiH leads to strengthened northerly winds in the North China Plain (NCP). The WRF‐Chem model calculation reveals the strengthened northerly winds during the stronger SiH period in January 2016 produce a significant decrease in PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) concentrations by 100–200 µg m−3 than that during the weaker one in January 2013. A sensitivity calculation figures out the reduction of PM2.5 concentrations due to a decrease of 50% in emissions is comparable to changes from the weak SiH condition to the strong SiH condition, suggesting that extreme climate variability in the past few years could have an equivalent impact as a consequence of a large emission reduction on wintertime air pollution in the NCP. [ABSTRACT FROM AUTHOR]

Background and Aims Recent genome-wide association studies have shown associations between variants in loci (4q28.1, 6p21.32, 6p21.1, 6q16.1, 10q22.1 and 10q22.3) and chronic obstructive pulmonary disease (COPD) or smoking behaviors. The objective of this study was to look for associations between 16 single nucleotide polymorphisms (SNP) at these six loci and COPD susceptibility in Hainan region. Methods A case-control cohort was composed of 200 COPD cases and 401 controls that were genotyped and analyzed statistically. Odds ratios (OR) and 95% confidence intervals (CIs) were computed by chi-square (χ2) test and genetic models by unconditional logistic regression. Results After Hardy-Weinberg equilibrium (HWE) P value screening, we excluded the SNP rs12220777 with P < 0.001. By χ2 test only rs9296092 which located on 6p21.32 was provided the strongest evidence of an increasing risk of COPD with an OR of 3.28 (95% CI = 1.03 - 2.32; P = 0.003) between cases and controls. By genetic models analysis, we not only found rs9296092 increased COPD risk, but also found in the over-dominant model the genotype 'C/T' (OR = 0.55; 95% CI = 0.33 - 0.93; P = 0.023) of rs950063 was proved to be associated with decreased COPD risk. Conclusions This study is the first to provide evidence of importance of rs9296092 and rs950063 for risk of COPD in Hainan Province. Further studies are needed to characterize the functional sequences that cause COPD. [ABSTRACT FROM AUTHOR]

CRM197 is a naturally nontoxic diphtheria toxin mutant that binds and inhibits heparin-binding epidermal growth factor-like growth factor. CRM197 serves as carrier protein for vaccine and other therapeutic agents. CRM197 also inhibits the growth, migration, invasion, and induces apoptosis in various tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we aimed to investigate the role and mechanism of CRM197 combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion, and apoptosis of glioblastoma cells. U87 and U251 human glioblastoma cells were treated with CRM197 (10 µg/ml) and shRNA interfering technology was employed to silence VCAM-1 expression. Cell viability, migration, invasiveness, and apoptosis were assessed with CCK8, Transwell and Annexin V-PE/7-AAD staining. Activation of cleaved caspase-3, 8, and 9, activity of matrix metalloproteinase-2/9 (MMP-2/9), and expression of phosphorylated Akt (p-Akt) were also checked. Results showed that CRM197 and shRNA-VCAM-1 not only significantly inhibited the cell proliferation, migration, invasion, but also promoted the apoptosis of U87 and U251 cells. Combined treatment of both displayed enhanced inhibitory effects on the malignant biological behavior of glioma cells. The activation of cleaved caspase-3, 8, 9 was promoted, activity of MMP-2 and MMP-9 and expression of p-Akt were inhibited significantly by the treatment of CRM197 and shRNA-VCAM-1 alone or in combination, indicating that the combination of CRM197 with shRNA-VCAM-1 additively inhibited the malignant behavior of human glioblastoma cells via activating caspase-3, 8, 9 as well as inhibiting MMP-2, MMP-9, and Akt pathway. J. Cell. Physiol. 230: 1713-1728, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background and aims: Great interest persists in useful therapeutic targets in glioblastoma (GBM). Deregulation of microRNAs (miRNAs) expression has been associated with cancer formation through alterations in gene targets. In this study, we reported the role of miR-101 in human glioblastoma stem cells (GSCs) and the potential mechanisms. Methods and results: Quantitative real-time PCR showed that miR-101 expression was decreased in GSCs. Overexpression of miR-101 reduced the proliferation, migration, invasion, and promoted apoptosis of GSCs. One direct target of miR-101, the transcription factor Kruppel-like factor 6 (KLF6), was identified using the Dual-Luciferase Reporter Assay System, which mediated the tumor suppressor activity of miR-101. This process was coincided with the reduced expression of Chitinase-3-like protein 1 (CHI3L1) whose promoter could be bound with and be promoted by KLF6 demonstrated by luciferase assays and chromatin immunoprecipitation assays. The downregulation of CHI3L1 led to the inactivation of MEK1/2 and PI3K signal pathways. Furthermore, nude mice carrying the tumors of overexpressed miR- 101 combined with knockdown of KLF6 produced the smallest tumors and showed the highest survival rate. Conclusions: Our findings provided a comprehensive analysis of miR-101 and further defining it as a potential therapeutic candidate for GBM. [ABSTRACT FROM AUTHOR]

An efficient and environmentally friendly protocol has been developed for CuSO4-catalyzed N-arylation of nitrogen-containing nucleophiles with aryl halides in water. The method uses 2-hydroxybenzohydrazides as ligand, avoids the use of organic solvents, and tolerates functional groups well. [ABSTRACT FROM AUTHOR]

Electrochemistry. An electrochemical desaturative α‐acylation of cyclic N‐aryl amines to access α‐substituted enamines is reported in the Communication by Youai Qiu et al. (e202115178). [ABSTRACT FROM AUTHOR]