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Direct hydroxylation via the functionalization of tertiary benzylic C(sp(3))-H bonds is of great significance for obtaining tertiary alcohols, which find wide applications in pharmaceuticals as well as in fine chemical industries. However, current synthetic procedures use toxic reagents, and therefore, the development of a sustainable strategy for the synthesis of tertiary benzylic alcohols is highly desirable. To solve this problem, herein, we report a metal-free heterogeneous photocatalyst to synthesize the hydroxylated products using oxygen as the key reagent. Various benzylic substrates were employed into our mild reaction conditions to afford the desirable products in good to excellent yields. More importantly, the gram-scale reaction was achieved via harvesting direct solar energy and exhibited high quantity of the product. The high stability of the catalyst was proved via recycling the catalyst and spectroscopic analyses. Finally, a possible mechanism was proposed based on electron paramagnetic resonance and other experimental evidence.

The derivatives of 7-amino-6-nitro-[1,2,5]oxadiazolo[3,4-b]pyridine-1-oxide (named A–L) are optimized to obtain their molecular geometries and electronic structures at the both DFT-B3LYP/6-31+G(d,p) and DFT-B3PW91/6-31+G(d,p) levels of theory. Similar quantum chemical results are obtained by B3LYP and B3PW91 methods. The sublimation enthalpies and heats of formation (HOFs) in gas phase and solid state of these compounds were calculated. The detonation performance had been estimated via Kamlet-Jacobs equation. Sensitivity was evaluated by characteristic heights (H50). The results show that all the derivations have large positive HOFs values. The detonation properties (D = 9.54 km s–1, P = 40.89 GPa, Q = 2248.39 cal g–1) and impact sensitivities of derivative K are superior to the conventional explosives such as RDX, HMX. 7-Amino-6-nitro-5-nitro-[1,2,5]oxadiazolo[3,4-b]pyridine-1-oxide (derivative K) can be regarded as potential candidates of high energy density compounds.

Recent extensive studies of long non-coding RNAs (lncRNAs) have shown that lncRNAs play an important role in plant development and growth. Populus euphratica Oliv. is the only natural tree species in the Taklimakan desert with leaves that change shapes at different growth stages. LncRNAs can affect biological functions in P. euphratica heterophyllous morphogenesis, but there are few reports on this subject in the literature. In this study, chain-specific transcriptome sequencing and small RNA sequencing were performed using linear, lanceolate, broad-ovate and ovoid leaves of P. euphratica. A total of 442 novel P. euphratica lncRNAs were predicted and the expression profiles of 4460 lncRNAs were analyzed. 371 lncRNAs were significantly different among the varied leaf shapes studied. Using co-expression analysis and according to the principle of competing endogenous RNA (ceRNA), we found that 28 lncRNAs could regulate the expression of 133 mRNAs by antagonizing 17 miRNAs. These mRNAs are involved in 23 biological functions, such as cell growth, developmental processes, metabolic processes and biological regulation, thereby affecting the formation of P. euphratica heteromorphic leaves. These results provide the foundation to study the formation of P. euphratica heteromorphic leaves, revealing the function of lncRNAs in the development of leaves in plants.

Populus euphratica Oliv. has typical heterophylly. Linear, lanceolate, ovate and broad-ovate leaves appeared in turn from sprouting to development, to maturity. The environmental adaptabilities of P. euphraticas with different leaves were also different. To explore the role of circRNAs on the morphogenesis of P. euphratica heteromorphic leaves (P.hl) and their stress response, the expression profile of circRNAs was analyzed by strand-specific RNA sequencing for the above four kinds of heteromorphic leaves. According to ceRNA hypothesis, 18 differentially expressed cirRNAs (DECs) could influence the expression of 84 mRNAs by antagonizing 23 miRNAs in five sample-pairs. Based on the function of 84 mRNAs, these DECs participate in development process, response to stimulus, response to hormonal et al. Therefore, these circRNAs were involved in the P.hl morphogenesis and stress response by interacting with miRNAs and mRNAs. Our study complemented the genebank of P. euphratica and provided a new strategy for studying leaf development.

With the booming of deep learning, massive attention has been paid to developing neural models for multilabel text categorization (MLTC). Most of the works concentrate on disclosing word-label relationship, while less attention is taken in exploiting global clues, particularly with the relationship of document-label. To address this limitation, we propose an effective collaborative representation learning (CRL) model in this article. CRL consists of a factorization component for generating shallow representations of documents and a neural component for deep text-encoding and classification. We have developed strategies for jointly training those two components, including an alternating-least-squares-based approach for factorizing the pointwise mutual information (PMI) matrix of label-document and multitask learning (MTL) strategy for the neural component. According to the experimental results on six data sets, CRL can explicitly take advantage of the relationship of document-label and achieve competitive classification performance in comparison with some state-of-the-art deep methods.

Circular RNAs (circRNAs) and long-noncoding RNAs (lncRNAs) are a class of non-protein-coding RNA, in eukaryotic genomes, that participate in the regulation of physiological and pathological processes such as stem cell maintenance, cell differentiation, cell growth, apoptosis, signal transduction, and immune response. In this study, based on RNA-Seq and competing endogenous RNAs hypothesis, 14 circRNAs and 28 lncRNAs, involved in the regulation of salt stress response were screened and identified from the RNA-Seq of Populus euphratica Oliv. heteromorphic leaves (P. hl), and their functions were predicted. We found that these circRNAs and lncRNAs may not only enhance the tolerance of plants to salt stress by participating in biological events such as ion compartmentation, oxidative stress, and cell division in plant cells but also play an important role in the occurrence of P. hl by participating in gene expression regulation, metabolism, and hormone regulation. This study provides theoretical support for studying the regulation mechanism of salt stress response of Populus euphratica Oliv., and lays an important foundation for using Populus euphratica Oliv. gene resources to cultivate new salt-resistant varieties.

The desert plant Populus euphratica Oliv. has typical heterophylly; linear (Li), lanceolate (La), ovate (Ov) and broad-ovate (Bo) leaves grow in turn as trees develop to maturity. P. euphratica is therefore a potential model organism for leaf development. To investigate the roles of RNAs (including mRNAs, miRNAs, lncRNAs and circRNAs) in the morphogenesis of P. euphratica heterophylls, juvenile heterophylls were sampled individually, and then, the expression patterns of miRNAs, mRNAs, lncRNAs and circRNAs were analysed by small RNA sequencing and strand-specific RNA sequencing. We found that 1374 mRNAs, 19 miRNAs, 71 lncRNAs and 2 circRNAs were P. euphratica heterophyll morphogenesis–associated (PHMA) RNAs; among them, 17 PHMA miRNAs could alter the expression of 46 PHMA mRNAs. Furthermore, 11 lncRNAs and 2 circRNAs interacted with 27 PHMA mRNAs according to the ceRNA hypothesis. According to GO and KEGG pathway analysis, PHMA RNAs were mainly involved in metabolism, response to stimulus and developmental processes. Our results indicated that external environmental factors and genetic factors in P. euphratica co-regulated the expression of PHMA RNAs, repressed cell division, reinforced cell growth, and ultimately resulted in the morphogenesis of P. euphratica heterophylls.

Circular RNAs (circRNAs) are a novel class of non-coding RNAs that are characterized by a covalently closed circular structure. They have been widely found in Populus euphratica Oliv. heteromorphic leaves (P. hl). To study the role of circRNAs related to transcription factors (TFs) in the morphogenesis of P. hl, the expression profiles of circRNAs in linear, lanceolate, ovate, and broad-ovate leaves of P. euphratica were elucidated by strand-specific sequencing. We identified and characterized 22 circRNAs related to TFs in P. hl at the four developmental stages. Using the competing endogenous RNAs hypothesis as a guide, we constructed circRNA–miRNA–TF mRNA regulatory networks, which indicated that circRNAs antagonized microRNAs (miRNAs), thereby influencing the expression of the miRNA target genes and playing a significant role in transcriptional regulation. Gene ontology annotation of the target TF genes predicted that these circRNAs were associated mainly with the regulation of leaf development, leaf morphogenesis, signal transduction, and response to abiotic stress. These findings implied that the circRNAs affected the size and number of cells in P. hl by regulating the expression of TF mRNAs. Our results provide a basis for further studies of leaf development in poplar trees.

Polyhedral oligomeric silsesquioxane (POSS)-coated nanodiamonds (NDs@POSS) were prepared via the amide formation between amine-functionalized POSS and oxygen-containing groups of NDs. The POSS structures grafted on the surface of NDs enable the NDs@POSS nanocomposites to be well-dispersed in organic solvents and polymers for multifunctional applications. The surface coating of NDs with POSS also bring other incidental advantages such as enhanced thermal stability and superhydrophobic of the NDs. NDs@POSS nanocomposites-embedded hybrid films based on polycarbonate and polyvinyl butyral were fabricated by solution blending methods, showing tunable refractive indexes in the range of 1.49–1.61. Furthermore, the powders of NDs@POSS were superhydrophobic with contact angle of water/air of 154°. Liquid marbles formed by coating the water droplet with NDs@POSS were prepared, and the process intensification effects of the NDs@POSS-based miniature reactors for degradation of methylene and fabrication of Ag nanoparticles were also demonstrated, respectively.

The poplar species Populus euphratica Oliv. exhibits a typical heterophylly; lanceolate and broad-oval leaves grow on young and adult trees, respectively. It is therefore an ideal model species for studying leaf shape development. MicroRNAs (miRNAs) have important regulatory functions in plant growth and development, such as the developmental regulation of adaxial–abaxial polarity. To investigate the miRNAs involved in the development of the apical–basal and medial–lateral axes of P. euphratica leaves, an unfolded piece method and microscopy measuring techniques were employed to study the leaf shape variations between lanceolate and broad-oval leaves within buds. We found that the leaf shape of P. euphratica is determined between the first and the third or fifth macroscopic leaf during the germination period. The first three tender leaves of lanceolate and broad-oval leaf buds were obtained to construct six cDNA libraries from small RNAs. MicroRNAs were identified using high-throughput sequencing, and 165 novel miRNAs were found. By comparing the expression levels of the miRNAs between these two kinds of samples (lanceolate and broad-oval leaves), we found that nine miRNAs (six novel miRNAs and three conserved miRNAs) and their 113 target genes are involved in the development of the apical–basal and medial–lateral axes. The expression profiles of these miRNAs and their targets were further validated by quantitative reverse transcription polymerase chain reaction. Moreover, functional information on the targets was annotated using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases.

Remote control of microfluidic locomotion by external stimuli is attracting extensive attention due to its practical applications in various areas such as chemical reactors, gas sensors and transporters. Within this report we describe an effective method of preparing liquid marbles (LMs) stabilized by super-hydrophobic luminescent carbon dots (CDs) and demonstrate their outstanding photothermics, fluorescence and diamagnetism. The super-hydrophobic CDs were synthesized by surface functionalization using polyhedral oligomeric silsesquioxane (POSS) and manipulation of the LMs was achieved using light, electricity and magnetism. LMs could act as ideal models of collision-triggered miniature reactors for enhanced chemical reactions, with fast mixing of microfluidics leading to substantial improvement in reaction rate and selectivity. For the first time, the use of collisions triggered by multi-external stimuli has been demonstrated, showing an intensification to the micromixing process and therefore an enhancement to the microreactions. We expect that these LMs can be applicable in microfluidics, miniaturized reactors and many other associated industries.

In recent years, many efforts based on deep learning have been made to address the issue of text tagging. However, these work generally neglect to consider the neighborhood effect which may help improve the accuracy of predictions. For this, we present a neighborhood-aware deep model for text tagging (NATT). A neural component which combines bi-directional recurrent neural network and self-attention mechanism, is firstly selected as the text encoder to encode the target document into one feature vector. Then, k-nearest-neighbor documents of the target document are identified and encoded into feature vectors one by one with the same text encoder. Simultaneously, an independent attention module is introduced to aggregate these neighboring documents into a special feature vector, which will represent features of the neighborhood. Finally, the two feature vectors are fused to match the embedding vectors of tags. To optimize the NATT model, we build the objective function with pairwise hinge loss and specially develop a neighborhood-aware negative sampling strategy to form training data. Experimental results on four datasets demonstrate that NATT outperforms some state-of-the-art neural models. Additionally, NATT is economical on achieving the best results with less training epochs and a smaller number of nearest neighbors.

An extracellular lipase from Yarrowia lipolytica (YlLip2) has been purified by ion exchange chromatography on Q sepharose FF, followed by hydrophobic interaction chromatography on butyl sepharose FF. SDS-PAGE showed that the molecular weight of this lipase is about 38 kDa. N-terminal amino acid sequencing and MALDI-TOF mass spectral analysis showed that this lipase is encoded by gene LIP2 (GenBank accession no. AJ012632 ). Enzymatic deglycosylation showed that this lipase is a glycosylated protein which contains about 12% sugar. The corresponding deglycosylated lipase remained 88% specific activity of untreated lipase. There was a high amino acid sequence identity (91%) between YlLip2 and Candida deformans lipase CdLip1 (GenBank accession no. AJ428393 ). The optima temperature and pH for the purified lipase was 40 °C and 8.0, respectively. The lipase showed a preference for long chain fatty acid methyl esters (C12–C16), with the highest activity toward methyl myristate (C14). Lipase activity was stimulated by Ca 2+ and Mg 2+ and inhibited by Zn 2+ , Ni 2+ and Cu 2+ , whereas EDTA had no effect on its activity. A 0.1% of Tween 80 and Span 65 increased slightly the enzyme activity and SDS inhibited it.