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An efficient and versatile synthesis of alcohols via transfer hydrogenation from ketones with isopropanol, utilizing [Ni(6,6′‐(OH)2‐2,2′‐bpy)][Br2] under alkaline conditions, has been documented. It was noteworthy that many readily reducible or labile functional groups such as nitro, cyano, and halide, within the same molecular framework, did not undergo any change under the standard reaction conditions. Furthermore, the gram scale transfer hydrogenation reaction was successfully carried out with good yield using a common route with only a single purification by column chromatography. [ABSTRACT FROM AUTHOR]

Exercise‐induced microRNA (miRNA) and HIPPO pathways participate in the regulation of skeletal muscle plasticity but their underlying mechanisms remain unclear. We aimed to investigate the effect of high‐intensity interval training (HIIT) on miRNA expression and the HIPPO pathway in the skeletal muscle of aging rats to determine its role in the amelioration of muscle aging. Thirty‐six 18‐month‐old female rats were randomly divided into sedentary control (SED, n = 12), moderate‐intensity continuous training (MICT, n = 12), and HIIT (n = 12) groups, with continuous exercise for 8 months. Quantitative reverse transcription‐polymerase chain reaction, immunoblotting, KEGG enrichment, and dual‐luciferase assays were performed on the target skeletal muscle. Compared with the SED group, the MICT and HIIT groups showed a significant trend of improvement in Lee's index and grip strength and a marked increase in skeletal muscle mitochondrial function, apoptosis, antioxidant, and lipolysis‐related protein expression. They also exhibited PI3K/AKT pathway activation and a decrease in expression of HIPPO pathway‐related proteins; 20 miRNAs were differentially expressed and enriched in the exercise group compared with the SED group, including the HIPPO pathway and metabolic pathways. Further analysis of L6 cells confirmed that miR‐182 may target PTEN, which indirectly regulates HIPPO signaling, but not Mob1. the combined application of HIIT and MICT increased the antioxidant and lipolytic capacities of skeletal muscle and improved atrophy of aging skeletal muscle; HIIT was more effective than MICT. This may be related to HIIT‐mediated AKT pathway activation and HIPPO pathway inhibition by miRNAs (miR‐486 and miR‐182). [ABSTRACT FROM AUTHOR]

Si69 and Si75, typical commodities of silane coupling agents, are often employed in tire recipes to work as the bridges connecting silica and polymers, with which rolling resistance and wet traction are enhanced without loss in abrasion resistance. In this article, the reactivities of Si69 and Si75 with silica and various rubbers were theoretically investigated by using density functional theory (DFT). When the agents were coupled with silica, not only the acid+water condition but also the pure acid condition was confirmed to readily trigger the condensation reactions. The corresponding Gibbs free energy barriers were related to the charge distributions of reaction regions. As the agents suffered from the homolysis of central SS bonds, the generated single‐S‐tailer radicals (RS·) showed significantly higher reactivities of both the radical addition and the α‐H transfer reactions with rubbers, due to the stronger radical philicities of the terminal sulfur radicals with larger condensed local softnesses [s0(S)]. When the agents underwent the heterolysis of central SS bonds, the terminal sulfur anions with smaller s−(S) indices, however, facilitated the nucleophilic addition reactions with rubbers. Several derivative indices based on the condensed local softnesses were also proposed here to shed light on the reactivities from the viewpoint of the relationship between energy barriers and electronic characteristics. The above findings pave the way for the design of new kinds of silane coupling agents using computer‐aided techniques, and meanwhile, provide references for the practical application of Si69 and Si75 to the silica/rubbers systems. [ABSTRACT FROM AUTHOR]

Fe3+ is a promising dopant for designing near‐infrared (NIR) phosphors due to its broadband emitting, non‐toxic, and inexpensive properties. However, the 4E (4D) and 4E + 4A1 (4G) levels of Fe3+ ions are independent of the crystal‐field parameter, and the spectral regulation has become a huge challenge. Herein, a broadband NIR‐emitting phosphor Ca2.5Hf2.5(Ga, Al)3O12: Fe3+ is successfully developed toward long‐wave ultraviolet (LWUV) light‐pumped NIR phosphor‐converted LED (pc‐LED). Significantly, the excited transition reverse of Ca2.5Hf2.5Ga3O12: Fe3+ can be realized by simply adjusting Fe3+ concentration, which results in the largely enhanced excitation around 410 nm and matches well with the commercial LWUV LED. Moreover, Ca2.5Hf2.5Ga3O12: Fe3+ can exhibit a broadband NIR emission centered at 770 nm with optimized doping content at 0.01 mol%, which are demonstrated to ascribe to Fe3+ occupying both octahedral Hf 4+ and tetrahedral Ga3+ sites. Further, a simple cation modulation strategy is proposed to successfully break the lattice symmetry around Fe3+ ions and largely enhance the NIR‐emission intensity to 200% as much as before. Finally, a NIR pc‐LED is fabricated by employing Ca2.5Hf2.5Ga3O12: Fe3+, Al3+ coating on a 410 nm LED chip, which shows great potential in non‐destructive inspection applications. [ABSTRACT FROM AUTHOR]

This study simulates the distributions of 13 endemic and near-endemic genera ( Ammopiptanthus, Sympegma, Iljinia, Elachanthemum, Potaninia, Tugarinovia, Kaschgaria, Sarcozygium, Timouria, Zollikoferia, Stilpnolepis, Synstemon and Tetraena) to indicate areas of plant diversity and conservation importance within the eastern Central Asian desert, and to identify the determinant environmental variables contributing to the spatial distribution patterns. Using known distribution localities and 14 environmental variables, the Maxent and Domain species distribution models were employed to map the patterns of geographic distribution. The power of predictability of the models was tested using the receiver operating characteristic method and the jackknife validation approach, according to the different number of species localities available. The estimated richness and the superimposed potential distributions of 13 genera were used to indicate endemic patterns of distribution. The comparison of Maxent and Domain further identified previously unknown areas of endemism and described the distribution for each taxon. Both observed species occurrence and the species occurrence predicted from the Maxent indicated that the eastern Alashan of Inner Mongolia is the most noticeable endemic area, and the northwestern and northern Tarim Basin of Xinjiang is the secondary center of plant diversity. These regions were then prioritized for conservation importance. Potential evapotranspiration ratio and precipitation seasonality played important roles in driving the observed patterns of endemic distribution. [ABSTRACT FROM AUTHOR]

We studied the arid shrub Amygdalus pedunculata to better understand biogeographic histories and the impact of climate fluctuations during the Quaternary in shaping genetic variation and in northwest China. Three chloroplast DNA intergenic spacers (psbK‐psbI, trnL‐trnF and trnV) were sequenced in 129 individuals from 10 populations across the range of A. pedunculata, and 17 haplotypes were identified, with one haplotype that was distributed across all sampled populations. High levels of total gene diversity (HT = 0.965) and within‐population diversity (HS = 0.669) were identified. Analysis of molecular variance (AMOVA) indicated that most genetic variation occurred within populations. Neutrality tests and mismatch distribution analysis suggested past range expansions of A. pedunculata. As such, A. pedunculata has likely undergone a substantial postglacial range expansion northward and southward along the margins of the northern Yin Mountains and Mu Us Desert, respectively. Principal coordinate analyses, median‐joining network analysis and Beast analysis revealed that 17 haplotypes mainly formed three clusters, corresponding to the Northern (Damao Banner) and Central (Wula Mountains and Guyang County) regions of Inner Mongolia and the Southern region (Bulang Township) in northern Shannxi. The local adaptative differentiation is speculated to have occurred among the three regions mainly resulting from geographical isolation caused by the uplift and extension of the Yinshan Mountains during the Quaternary. [ABSTRACT FROM AUTHOR]

Integrating multiple mechanisms to maximize photothermal conversion efficiency is a significant strategy but remains challenging to construct therapeutic agents toward photothermal tumor treatment. Here, an approach to synthesize asymmetric Bi2Se3/CdSe‐Au hierarchical nanorods with excellent photothermal conversion is reported. Ag wetting‐layer is firstly grown to help overcome the interfacial lattice mismatch and promote the site‐selective growth of AgCdSe onto one end or side surface of Au nanorods. Subsequently, extraction of Ag+ ions out of lattice is observed during cation exchange reaction and epitaxial growth of Bi2Se3 shell. Bi2Se3/CdSe heterojunction with type‐II band alignment is formed and located at the plasmonic hotspots of Au nanorods, which experiences enhanced light absorption and accelerates the charge separation of photo‐excited carriers. Under excitation of near‐infrared 808 nm laser, the matchstick‐like Bi2Se3/CdSe‐Au nanorods show an excellent photothermal conversion, with 4.3 times temperature increment (ΔT) than that of bare Au nanorods. Moreover, in vitro and in vivo experiments verify them as excellent photothermal therapeutic agents. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play important roles in the initiation and progression of various cancers, including laryngeal squamous cell carcinoma (LSCC). Recently, lncRNA Sox2 overlapping transcript (SOX2‐OT) has been identified as an oncogene in various cancers. However, the functional role and the regulatory mechanism of SOX2‐OT in LSCC remains unclear. In this study, we found that SOX2‐OT expression was increased and negatively correlated with PTEN expression in LSCC tissues. Furthermore, SOX2‐OT overexpression promoted LSCC cell proliferation, migration, invasion, and suppressed cell apoptosis in vitro, as well as facilitated the in vivo tumorigenicity. By contrast, SOX2‐OT silencing exerted the opposite effect. Mechanically, SOX2‐OT interacted with EZH2 and recruited EZH2 to induce H3K27me3 and epigenetically inhibited PTEN expression in LSCC cells. Additionally, EZH2 silencing and PTEN overexpression significantly abrogated the SOX2‐OT overexpression‐mediated promotion of LSCC cell malignant behavior. Collectively, our findings demonstrate that SOX2‐OT inhibits PTEN expression to facilitate LSCC development through EZH2‐mediated H3K27me3. © 2019 IUBMB Life, 71(9):1230–1239, 2019 [ABSTRACT FROM AUTHOR]

Carrier density control is of great importance to modulate the topological phase and topological transport for the topological crystalline insulators (TCIs). Here, the transport property modulation of TCI SnTe thin films grown on SrTiO3 (111) by tuning the carrier density is reported. The low temperature magneto‐transport in a typical SnTe film with high hole carrier density in the as grown films exhibits a giant linear magnetoresistance (GLMR) effect (up to 1849% at 2 K under 14 T) and then the magnetoresistance becomes much weaker and weak anti‐localization (WAL) appears in the same SnTe film by n‐type doping in vacuum after aging 30 days. Alternatively, the hole carrier density of the as grown SnTe films is lowered by enhancing the growth temperature to promote Sn diffusion to reduce Sn vacancies and the as grown samples exhibit a WAL with two‐dimensional (2D) characteristics. This work provides promising application for magnetoelectronic sensors and spintronics based on TCI SnTe thin film. [ABSTRACT FROM AUTHOR]