Direct synthesis of N‐(hetero)arylated heteroarenes has been realized through Cu‐mediated C−N coupling of NH azaheterocycles with aryl C−H bonds under aerobic conditions. This method features a broad ...scope of both heterocyclic arenes (pyridine, quinoline, pyrazole, imidazole, furan, thiophene, benzofuran, and indole) and NH azaheterocycles (imidazole, pyrazole, indole, azindole, purine, indazole, benzimidazole, pyridone, carbazole), providing a versatile method for the synthesis of pharmaceutically important N‐(hetero)arylated heteroarenes. The versatility of this reaction was further demonstrated through late‐stage modification of marketed drugs and the synthesis of a key intermediate for accessing a class of angiotensin II receptor 1 antagonists.
N‐(hetero)arylated heteroarenes were synthesized through Cu‐mediated C−H amination with NH azaheterocycles. This directing‐group (DG)‐mediated reaction proceeds with air as the sole oxidant, and its outstanding compatibility with heterocycles enables late‐stage diversification of a wide range of drug compounds containing multiple heterocycles.
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•Novel wind speed interval forecasting approach in multi-objective formulation introduced.•Hybrid framework building on data feature selection method.•Simultaneously the lower and upper bounds of the ...prediction intervals of future wind speed time series constructed.•The best compromise solution selected by the smallest coverage width criterion method.
Accurate forecast of wind speed is the first prerequisite to supply high quality power energy to customer in a secure and economic manner. However, traditional point forecast may not be sufficiently reliable and accurate for decision-makers to perform operational strategies purely when the uncertainty level increases. For the sake of quantifying the uncertainty associated with point predictions, it is necessary to conduct interval prediction to provide reliable and accurate wind speed information. In this work, a hybrid model framework based on combinatorial modules was proposed and successfully adopted to construct the prediction intervals of the future wind speed. Feature selection methods are developed to determine the most suitable modes of original time series and the optimal input form of the model, while the optimization forecasting module is applied to model the wind speed series based on the machine learning method and the multi-objective optimization algorithm, then the compromise solution of Pareto front is chosen by “Min-max” method. Finally, the proposed combined model was investigated via the hourly wind speed data from two different periods in Penglai, China. Besides, the study’s experimental results indicated that the prediction intervals generated perform well and are satisfactory in both criterion functions of high coverage and small width through discussion among single-objective models and other multi-objective models (signal pre-processing method comparison included).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Although thousands of long noncoding RNAs (lncRNAs) have been annotated, only a limited number of them have been functionally characterized. Here, we identified an oncogenic lncRNA, named lnc‐UCID ...(lncRNA up‐regulating CDK6 by interacting with DHX9). Lnc‐UCID was up‐regulated in hepatocellular carcinoma (HCC), and a higher lnc‐UCID level was correlated with shorter recurrence‐free survival of HCC patients. Both gain‐of‐function and loss‐of function studies revealed that lnc‐UCID enhanced cyclin‐dependent kinase 6 (CDK6) expression and thereby promoted G1/S transition and cell proliferation. Studies from mouse xenograft models revealed that tumors derived from lnc‐UCID‐silenced HCC cells had a much smaller size than those from control cells, and intratumoral injection of lnc‐UCID small interfering RNA suppressed xenograft growth. Mechanistically, the 850‐1030‐nt domain of lnc‐UCID interacted physically with DEAH (Asp‐Glu‐Ala‐His) box helicase 9 (DHX9), an RNA helicase. On the other hand, DHX9 post‐transcriptionally suppressed CDK6 expression by binding to the 3′‐untranslated region (3′UTR) of CDK6 mRNA. Further investigation disclosed that lnc‐UCID enhanced CDK6 expression by competitively binding to DHX9 and sequestering DHX9 from CDK6‐3′UTR. In an attempt to explore the mechanisms responsible for lnc‐UCID up‐regulation in HCC, we found that the lnc‐UCID gene was frequently amplified in HCC. Furthermore, miR‐148a, whose down‐regulation was associated with an increase of lnc‐UCID in HCC, could bind lnc‐UCID and inhibit its expression. Conclusion: Up‐regulation of lnc‐UCID, which may result from amplification of its gene locus and down‐regulation of miR‐148a, can promote HCC growth by preventing the interaction of DHX9 with CDK6 and subsequently enhancing CDK6 expression. These findings provide insights into the biological functions of lncRNAs, the regulatory network of cell cycle control, and the mechanisms of HCC development, which may be exploited for anticancer therapy.
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Driven by the persisting poor understanding of the sluggish kinetics of the hydrogen evolution reaction (HER) on Pt in alkaline media, a direct correlation of the interfacial water structure and ...activity is still yet to be established. Herein, using Pt and Pt–Ni nanoparticles we first demonstrate a strong dependence of the proton donor structure on the HER activity and pH. The structure of the first layer changes from the proton acceptors to the donors with increasing pH. In the base, the reactivity of the interfacial water varied its structure, and the activation energies of water dissociation increased in the sequence: the dangling O−H bonds < the trihedrally coordinated water < the tetrahedrally coordinated water. Moreover, optimizing the adsorption of H and OH intermediates can re‐orientate the interfacial water molecules with their H atoms pointing towards the electrode surface, thereby enhancing the kinetics of HER. Our results clarified the dynamic role of the water structure at the electrode–electrolyte interface during HER and the design of highly efficient HER catalysts.
On nickel–platinum alloy nanoparticles under alkaline conditions, the reactivity of interfacial water varies with its structure and the order of water dissociation. The inclusion of nickel re‐orientates interfacial water molecules with their hydrogen atoms pointing towards the electrode surface, thereby enhancing the kinetics of the hydrogen evolution reaction (HER).
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Three data fusion strategies (low-llevel, mid-llevel, and high-llevel) combined with a multivariate classification algorithm (random forest, RF) were applied to authenticate the geographical origins ...of
Panax notoginseng
collected from five regions of Yunnan province in China. In low-level fusion, the original data from two spectra (Fourier transform mid-IR spectrum and near-IR spectrum) were directly concatenated into a new matrix, which then was applied for the classification. Mid-level fusion was the strategy that inputted variables extracted from the spectral data into an RF classification model. The extracted variables were processed by iterate variable selection of the RF model and principal component analysis. The use of high-level fusion combined the decision making of each spectroscopic technique and resulted in an ensemble decision. The results showed that the mid-level and high-level data fusion take advantage of the information synergy from two spectroscopic techniques and had better classification performance than that of independent decision making. High-level data fusion is the most effective strategy since the classification results are better than those of the other fusion strategies: accuracy rates ranged between 93% and 96% for the low-level data fusion, between 95% and 98% for the mid-level data fusion, and between 98% and 100% for the high-level data fusion. In conclusion, the high-level data fusion strategy for Fourier transform mid-IR and near-IR spectra can be used as a reliable tool for correct geographical identification of
P. notoginseng
.
Graphical abstract
The analytical steps of Fourier transform mid-IR and near-IR spectral data fusion for the geographical traceability of
Panax notoginseng
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Due to its wide applications, remote sensing (RS) image scene classification has attracted increasing research interest. When each category has a sufficient number of labeled samples, RS image scene ...classification can be well addressed by deep learning. However, in the RS big data era, it is extremely difficult or even impossible to annotate RS scene samples for all the categories in one time as the RS scene classification often needs to be extended along with the emergence of new applications that inevitably involve a new class of RS images. Hence, the RS big data era fairly requires a zero-shot RS scene classification (ZSRSSC) paradigm in which the classification model learned from training RS scene categories obeys the inference ability to recognize the RS image scenes from unseen categories, in common with the humans' evolutionary perception ability. Unfortunately, zero-shot classification is largely unexploited in the RS field. This article proposes a novel ZSRSSC method based on locality-preservation deep cross-modal embedding networks (LPDCMENs). The proposed LPDCMENs, which can fully assimilate the pairwise intramodal and intermodal supervision in an end-to-end manner, aim to alleviate the problem of class structure inconsistency between two hybrid spaces (i.e., the visual image space and the semantic space). To pursue a stable and generalization ability, which is highly desired for ZSRSSC, a set of explainable constraints is specially designed to optimize LPDCMENs. To fully verify the effectiveness of the proposed LPDCMENs, we collect a new large-scale RS scene data set, including the instance-level visual images and class-level semantic representations (RSSDIVCS), where the general and domain knowledge is exploited to construct the class-level semantic representations. Extensive experiments show that the proposed ZSRSSC method based on LPDCMENs can obviously outperform the state-of-the-art methods, and the domain knowledge further improves the performance of ZSRSSC compared with the general knowledge. The collected RSSDIVCS will be made publicly available along with this article.
A cluster of pneumonia cases were reported by Wuhan Municipal Health Commission, China in December 2019. A novel coronavirus was eventually identified, and became the COVID-19 epidemic that affected ...public health and life. We investigated the psychological status and behavior changes of the general public in China from January 30 to February 3, 2020.
Respondents were recruited via social media (WeChat) and completed an online questionnaire. We used the State-Trait Anxiety Inventory, Self-rating Depression Scale, and Symptom Checklist-90 to evaluate psychological status. We also investigated respondents' behavior changes. Quantitative data were analyzed by t-tests or analysis of variance, and classified data were analyzed with chi-square tests.
In total, 608 valid questionnaires were obtained. More respondents had state anxiety than trait anxiety (15.8% vs 4.0%). Depression was found among 27.1% of respondents and 7.7% had psychological abnormalities. About 10.1% of respondents suffered from phobia. Our analysis of the relationship between subgroup characteristics and psychological status showed that age, gender, knowledge about COVID-19, degree of worry about epidemiological infection, and confidence about overcoming the outbreak significantly influenced psychological status. Around 93.3% of respondents avoided going to public places and almost all respondents reduced Spring Festival-related activities. At least 70.9% of respondents chose to take three or more preventive measures to avoid infection. The three most commonly used prevention measures were making fewer trips outside and avoiding contact (98.0%), wearing a mask (83.7%), and hand hygiene (82.4%).
We need to pay more attention to public psychological stress, especially among young people, as they are likely to experience anxiety, depression, and psychological abnormalities. Different psychological interventions could be formulated according to the psychological characteristics of different gender and age groups. The majority of respondents followed specific behaviors required by the authorities, but it will take time to observe the effects of these behaviors on the epidemic.
A pair of propeller‐like chiral trinuclear CuI clusters (R/S‐Cu3) with unique photoinduced fluorescence enhancement were prepared. R/S‐Cu3 showed intense variable luminescence after UV light ...irradiation, which was attributed to the stepwise oxidation of ligand in the clusters. It exhibited typical aggregation‐induced emission (AIE) (αAIE=17.3). Mechanism studies showed that metal cluster‐centered (MCC) and triplet metal‐to‐ligand charge‐transfer (3MLCT) processes are the origin of the luminescence; the processes are regulated by a restriction of intramolecular motions mechanism in a different state. The chiral structure and AIE feature endow R/S‐Cu3 with remarkable circularly polarized luminescence (glum=2×10−2) in the aggregated state. It shows good capability for producing reactive oxygen species. This work enriches the kinds of atomically precise AIE clusters, gains insight into their luminescence mechanism, and offers the prospect of application in multifunctional materials.
All in a spin: A pair of propeller‐like chiral trinuclear CuI clusters with typical aggregation induced emission (AIE) features were developed. They exhibit exceptional photoinduced fluorescence enhancement.
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The existence of breast cancer stem cells (BCSCs) is a major reason underlying cancer metastasis and recurrence after chemotherapy and radiotherapy. Targeting BCSCs may ameliorate breast cancer ...relapse and therapy resistance. Here we report that expression of the pseudokinase Tribble 3 (TRIB3) positively associates with breast cancer stemness and progression. Elevated TRIB3 expression supports BCSCs by interacting with AKT to interfere with the FOXO1-AKT interaction and suppress FOXO1 phosphorylation, ubiquitination, and degradation by E3 ligases SKP2 and NEDD4L. The accumulated FOXO1 promotes transcriptional expression of SOX2, a transcriptional factor for cancer stemness, which in turn, activates FOXO1 transcription and forms a positive regulatory loop. Disturbing the TRIB3-AKT interaction suppresses BCSCs by accelerating FOXO1 degradation and reducing SOX2 expression in mouse models of breast cancer. Our study provides insights into breast cancer development and confers a potential therapeutic strategy against TRIB3-overexpressed breast cancer.
Summary
Malate, the predominant organic acid in many fruits, is a crucial component of the organoleptic quality of fruit, including taste and flavor. The genetic and environmental mechanisms ...affecting malate metabolism in fruit cells have been studied extensively. However, the transcriptional regulation of malate‐metabolizing enzymes and vacuolar transporters remains poorly understood. Our previous studies demonstrated that MdMYB1 modulates anthocyanin accumulation and vacuolar acidification by directly activating vacuolar transporters, including MdVHA‐B1, MdVHA‐E, MdVHP1 and MdtDT. Interestingly, we isolated and identified a MYB transcription factor, MdMYB73, a distant relative of MdMYB1 in this study. It was subsequently found that MdMYB73 protein bound directly to the promoters of MdALMT9 (aluminum‐activated malate transporter 9), MdVHA‐A (vacuolar ATPase subunit A) and MdVHP1 (vacuolar pyrophosphatase 1), transcriptionally activating their expression and thereby enhancing their activities. Analyses of transgenic apple calli demonstrated that MdMYB73 influenced malate accumulation and vacuolar pH. Furthermore, MdCIbHLH1 interacted with MdMYB73 and enhanced its activity upon downstream target genes. These findings help to elucidate how MdMYB73 directly modulates the vacuolar transport system to affect malate accumulation and vacuolar pH in apple.
Significance Statement
In this study we found that the R2R3‐MYB transcription factor MdMYB73 is involved in malate accumulation and vacuolar acidification in apple.
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