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We report herein two lemniscular carbon nanohoops bis-po-CC and bis-pm-TC with contiguous conjugation from planar chiral [2.2]paracyclophane, and elucidate the influence of the regioselective synthesis on their topological chirality.

We report the first highly diastereo- and enantioselective C–C bond-forming reaction of racemic α-branched ketones to construct tertiary alcohols with adjacent stereocenters. Accordingly, a highly ...

We describe here an approach for synthesizing quinolines either from

Owing to the flammability of dendrites and organic liquid electrolytes, the safety performance of lithium-ion batteries cannot be effectively ensured. The sodium-ion solid electrolyte is anticipated to become the leading next generation battery in commercial applications due to the high thermal stability and low price. Yet, the insufficient ionic conductivity of Na3Zr2Si2PO12 solid electrolytes, along with the large interfacial resistance between the cathode material and the solid electrolyte, substantially restricts the performance of room-temperature all-solid-state sodium rechargeable batteries. In the present study, the effects of Bi2O3 additive on the phase, microstructure and ionic conductivity of Na3.1Y0.1Zr1.9Si2PO12 ceramic electrolyte are reported. Moreover, a significant room temperature conductivity of 1.21 × 10-3 S cm-1 and the dense microstructure was attained by adding 1 wt% Bi2O3 to Na3.1Y0.1Zr1.9Si2PO12 sintered at 1100 °C for 6 h. Simultaneously, an electrochemical test exhibited that the electrochemical stability window increased to 4.8 V and revealed good cycle stability.

To study the influence of B4C particle size on the microstructure and damping capacities of (B4C+Ti)/Mg composites, in situ reactive infiltration technique was utilized to prepare Mg-matrix composites. The microstructure, produced phases and damping capacities of the composites prepared with different particle size of B4C were characterized and analyzed. The results show that the reaction between B4C and Ti tends to be more complete when finer B4C particle was used to prepare the composites. But the microstructure of the as-prepared composites is more homogenous when B4C and Ti have similar particle size. The strain-dependent damping capacities of (B4C+Ti)/Mg composites improve gradually with the increase of strain amplitude, and composites prepared with coarser B4C particles tend to have higher damping capacities. The temperature-dependent damping capacities improve with increasing the measuring temperatures, and the kind of damping capacities of the composites prepared with 5 B4C are inferior to those of coarser particles. The dominant damping mechanism for the strain-damping capacity is dislocation damping and plastic zone damping, while that for the temperature-damping capacity is interface damping or grain boundary damping.

Globba ruiliensis, a new species of Zingiberaceae from Ruili City, Yunnan Province, China, is described and illustrated. This new species is similar to G. multiflora, but clearly differs in its oblong or ovate-lanceolate leaves, 18–25 × 6–12 cm, adaxially strigose along veins, lateral staminodes are nearly equal to corolla lobes, 7–8 mm long, ovate-oblong, apex rounded, yellow to orange labellum, and verrucose ovary and fruit. A comparison table of related species is provided.

New antibiotics are urgently required in clinical treatment and agriculture with the development of antimicrobial resistance. However, products discovered by repeating previous strategies are either not antibiotics or already known antibiotics. There is a growing demand for efficient strategies to discover new antibiotics. With the continuous improvement of gene sequencing technology and genomic data, some mining strategies have emerged. These strategies are expected to alleviate the current dilemma of antibiotics. In this review, we discuss the recent advances in discovery of bacterial antibiotics from the following aspects: activation of silent gene clusters, genome mining and metagenome mining. In the future, we envision the discovery of natural antibiotic will be accelerated by the combination of these strategies.

The gene PSEN2 encodes presenilin-2, a subunit of γ-secretase. Mutations in PSEN2 are not only related to Alzheimer's disease but are also involved in other diseases. The Chinese tree shrew (Tupaia belangeri chinensis) is a potential animal model for Alzheimer's disease, although little is known about its cDNA sequence, protein structure, and PSEN2 expression. To better understand PSEN2 in the tree shrew, we cloned this gene by rapid amplification of cDNA ends technology. Hence, we analyzed the sequence and molecular characteristics of PSEN2 mRNA, predicted its spatial structure, and analyzed its expression profiles. We found that tree shrew PSEN2 is 1539 base pairs in length and encodes 330 amino acids. It is homologous and genetically similar to humans (97.64% identity). The protein structure of tree shrew PSEN2 indicated similarities to human PSEN2, both being comprised of numerous transmembrane helices. However, tree shrew PSEN2 possesses seven α-helices, and thus lacks three compared with human PSEN2. Tree shrew PSEN2 mRNAs were ubiquitously detected in all tissues, with a tissue- and temporal-specific pattern. These results pave the way towards the function of tree shrew PSEN2, which will give insights into the mechanisms leading to neurodegenerative and other diseases in humans.

Aspidistra purpureomaculata, a new species from Pakse, Laos, is described and illustrated. This new species resembles A. xuansonensis in the shape of perianth and stigma, but can be distinguished by its perianth tube colour mainly purple and stamens in the middle of the perianth tube. Aspidistra purpureomaculata is also similar to A. laongamensis in the shape of perianth and the position of stamens but is distinguishable by perianth lobes 6, pale green or white inside, and stigma 6-lobed. Detailed description is provided.

Stixis villiflora (Resedaceae), a new species from Mengla, Yunnan, China, is described and illustrated. It is compared with four morphologically similar species S. philippinensis, S. suaveolens, S. ovata subsp. fasciculata and S. scandens. It differs from the preceding species by both leaf surfaces being pubescent and full of pustules, stamens 14–18, filaments lower half pubescent, upper half sparsely pubescent or glabrous, androgynophores ca. 1 mm long, lower half glabrous, upper half tomentose, gynophores and ovary with densely white hairs. A complete morphological description of Stixis villiflora is provided, together with photographs, a conservation assessment, and a diagnostic key to 10 species and 1 subspecies of Stixis from Asia.

Begonia daunhitam, a new species from West Kalimantan, Indonesia with strongly bullate black leaves is described and illustrated here, and details of the distribution, ecology and conservation status are provided.

Allergic rhinitis (AR) is a chronic inflammatory disease of the nasal mucosa. M2 macrophage polarization can reduce inflammation and repair tissue injury during AR development. Studies have substantiated the involvement of miRNAs in AR pathogenesis. Herein, the molecular mechanism of miR-214-3p in AR development was explored. To mimic the AR environment, ovalbumin (OVA) was used to treat macrophages. MiR-214-3p and glycogen synthase kinase 3 beta (GSK3B) expression in nasal mucus tissues and macrophages was assessed by RT-qPCR. The M2 phenotypic signature of CD206 in macrophages was assessed by flow cytometry. The protein expression of GSK3B and M2 macrophage markers (ARG-1 and IL-10) was evaluated by western blotting. The correlation between miR-214-3p and GSK3B was validated by a luciferase reporter assay. We found that miR-214-3p was overexpressed in macrophages and nasal mucus tissues from AR patients. MiR-214-3p facilitated M2 polarization of macrophages upon OVA stimulation. Mechanistically, miR-214-3p targeted the GSK3B 3' untranslated region in macrophages. In addition, GSK3B was downregulated in macrophages and nasal mucus tissues from AR patients. In rescue assays, GSK3B downregulation reversed the inhibitory effects of miR-214-3p silencing on M2 polarization of macrophages treated with OVA. Overall, miR-214-3p facilitates M2 macrophage polarization by targeting GSK3B.

Ichtyoselmis macrantha subsp. porphyrantha J. Y. Shen & Q. B. Gong a new subspecies from West Yunnan and North Myanmar is described. The new subspecies differs from Ichtyoselmis macrantha subsp. macrantha by its outer petals purplish red and with minute red-purple spots as well as transversal lines on the apical swollen margin, and inner petals white with red-purple spots. It is distributed well to the Southwest of the distribution area of I. macrantha subsp. macrantha.

Begonia austroyunnanensis, a new species from Yunnan (China) is described and illustrated. This new species is similar to B. subhowii in having short erect stems, obliquely ovate leaves and white flowers, but can be distinguished by its stem, petioles and peduncle having conspicuous, red, linear dots and the much longer abaxial wing of the capsule. A detailed description, data on distribution, ecology and an illustration are provided.

Begonia zhongyangiana, a new species in Begonia sect. Platycentrum (Begoniaceae) from Motuo (SE Xizang, China), is described and illustrated. This new species is similar to B. versicolor, B. scintillans and B. smithiae, but can be distinguished by its shorter rhizome lacking or rarely with short stems when blooming, orange-yellow flowers, 2 styles and 2-loculed ovary.

Cynanchum brevipedunculatum (Apocynaceae), a new species from Menghai, Yunnan, China, is described and illustrated. It is compared with two morphologically similar species, Cynanchum decipiens and C. longipedunculatum. Cynanchum brevipedunculatum differs from the preceeding species in having much bigger leaves, adaxially sparsely strigillose, abaxially glabrous or sparsely strigillose on veins, shorter peduncle and the very distinctive bowl-shaped corona. A comprehensive morphological description of C. brevipedunculatum is provided, together with photographs, and a conservation assessment for this rare vine species.

Rhodococcus strains not only have been widely used in industries but also have a potential ability of producing new structural natural products. Integration of heterologous genes into chromosomes of Rhodococcus strains for gene expression can facilitate the studies and applications of these strains. A conjugation system was optimized in order to transfer enhanced green fluorescent protein (EGFP) encoding gene as a reporter from Escherichia coli into Rhodococcus erythropolis D-1. The influence of three native ribosome binding sites (RBSs) and two designed RBSs on the target protein production in R. erythropolis D-1 was also characterized. An efficient conjugation system of R. erythropolis D-1 was established to integrate EGFP gene into its chromosome. Among of five RBSs, RBS3 showed the highest translational activity in R. erythropolis D-1.

Begonia xishuangbannaensis W.G. Wang & L.J. Jiang (Begoniaceae), a new tuberous species from Yunnan, China, is described and illustrated. It belongs to Begonia sect. Diploclinium. Morphologically, it is similar to B. fimbristipula and B. exposita in its tuberous habit and pubescent leaves, but can be distinguished from both by its asymmetrical leaf blade, 16–18 stamens, filaments that are free at base, and pistillate flowers having five tepals.

The gene

Begonia puerensis sp. nov., a new tuberous species of Begonia sect. Reichenheimia (Begoniaceae) from Yunnan, China is described and illustrated. The morphological similarity between the new species and the similar species B. discreta, B. harmandii and B. qingchengshanensis is compared and discussed and a key to Begonia sect. Reichenheimia in China is provided. The new species is assessed as Endangered (EN) following the IUCN Red List Categories and Criteria.

To investigate the effect of smoking status, cumulative smoking exposure and smoking cessation on the outcomes of patient with non-muscle-invasive bladder cancer (NMIBC). We collected smoking data from 484 patients with NMIBC who were treated with transurethral resection (TUR); smoking status was categorized as (never smokers vs current smokers vs former smokers). Cumulative smoking exposure was categorized as high smoking exposure (cigarette index ≥400) versus low smoking exposure (cigarette index

Salacia malipoensis X.D. Ma & J.Y. Shen (Celastraceae), a new species from Malipo, Yunnan, China, is described and illustrated. It is similar to S. oblongifolia, S. glaucifolia, S. polysperma and S. menglaensis, but easily distinguished by 4–8 mm long petioles (8–17 mm long in S. oblongifolia, ca. 10 mm long in S. glaucifolia and S. polysperma, 8–10 mm long in S. menglaensis), crenulate or serrulate leaf margin (entire in S. glaucifolia and S. menglaensis, subentire to crenulate in S. oblongifolia, sinuate, weakly serrulate in S. polysperma), 1–3 mm long peduncle (ca. 5 mm long in S. oblongifolia, ca. 10 mm long in S. glaucifolia and S. polysperma, 5–20 mm long in S. menglaensis), reflexed petals (explanate in the other species), ovules 2 per locule (same in S. glaucifolia and S. menglaensis, ovules 4–6 per locule in S. oblongifolia, unknown in S. polysperma), and 1–2 seeds (1–2 seeds in S. menglaensis, usually 12 in S. polysperma, unknown in S. glaucifolia and S. polysperma). An identification key of all 12 Chinese species are provided.

This study is to detect candidate genes as potential cause forcataract in tree shrewsand to find novelclueto reveal the genetic pathogenesis of tree shrewcataract

A Markov repairable system with history-dependent up and down states is presented. The state space of the repairable system is divided into three sets, which are up states, down states and changeable states. Using aggregated stochastic processes, we can get the multi-interval availability and multi-point availability for the Markov repairable system. Finally, numerical examples are given to illustrate the obtained results.

Based on the data of core, thin section, scanning electron microscopy and geochemical analysis.etc, from the dissolution phenomenon of laumontite in the carboniferous volcanic reservoirs of Santanghu Basin,the exploratory study of alkaline diagenesis and the formation mechanism in volcanic reservoir was carried out.

Synthesis and characterization of a novel hexabenzocoronene (HBC) derivative attached with four alkyl swallow-tailed chains and two sulfur-containing chains are described. The designed peripheral decoration with dove tails as solubilizer and sulfur-containing groups as functionalizer is expected to improve the solubility of molecules, change the columnar spacing stacks and make for its orientation on matrix surface. Its UV−vis absorption spectra appeared in 350-400 nm region as same as typical that of this kind of compounds. The thermal properties as discotic liquid crystal and its orientation on matrix are being studied.

Inspired by the transition-metal-oxo cubical Mn

Synthesis and characterization of a novel hexabenzocoronene (HBC) derivative bearing swallow-tailed fluorinated alkoxy chains are described. The six peripheral fluorinated chains, well known for their low van der Waals forces, should result as expected in reduced inter-columnar interactions. The UV−vis absorption spectra of this compound appeared in 230-390 nm region. The thermal properties are waiting for the follow-up study.

LiFePO4/graphene composites were prepared via a simple hydrothermal method. The as-prepared LiFePO4/graphene composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), galvanostatic charge-discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests. The lithium-ion batteries using LiFePO4/graphene composites as cathode material exhibited a discharge capacity of 165 mAh/g, which was 97% of the theoretical capacity of 170 mAh/g.

By measuring the nail holding power used in the decoration of bamboo integrated timber, analyze the influence of bolt category,diameter of guiding bore and screwing depth. The results show that the bolt joint strength of bamboo integrated timber was obviously increased in usage with the decreasing of diameter of guiding bore and the increasing of screwing depth.

This paper based on the field outcrop ,core data, logging data , physical property data and testing data to research the weathering crust of the deep volcanic in xujiaweizi depression. Take red clay layer that developed on the top of volcanic rock as the identification mark, and take the logging response characteristics of volcanic rock weathering crust as division standard, to research weathering crust of volcanic rock. Results show that recognized 31 wells that developed volcanic rock weathering crust of deep K1yc1 and K1yc3 volcanic of xujiaweizi depression that mainly distributed in Xuzhong and Anda region. Find that the main components of weathering crust are composed of rhyolite, volcanic breccia and tuff, and divide out dissolution and disintegration belt that are in conformity with the actual gas reservoir exploration position.

The distribution of oil and water in Xinmiaoxi-Xinbei area Fuyu reservoir is very complicated and the variation of productivity is very large. The distribution on the whole is continuous,but there are special hydrocarbon accumulation characteristics that lower place oiliness but high location multi-water. From the six major geological factors: source, reservoir and cap rock, trap, migration,and preservation condition, synthetically considering the distribution of mature source rock, underwater distributary channels distribution, the matching relation of fault and sand, single trap and inherited palaeostructure, combined with the distribution regular of reservoir to study the enrichment regularity of research. Finally find that this research area has a accumulate characteristics, that is, ancient tectonic controlled potential, the single trap reservoir control the reservoir, lithology control boundary, single sand bodies control layer. Among these, the high ancient structure formed before the peak of hydrocarbon expulsion is the advantage point oil and gas migration, is also the main control factors of continuous distribution of oil and gas; Single trap is the main controlling factor of the complex oil-water distribution that "high position is water and low position is oil", and then we can determine the cause of the complex regularities of oil-water distribution.

In order to reduce the risk of the range missile experiment and decrease the cost of the range missile development, we design and implement a scene federate in the proving ground simulation platform based on HLA, and analyze and solve the key problems of entity behavior modeling, multi-channel display. By integrating the under tested radar measuring system, optical measuring system with the computer simulation system, utilizes the feature information of the proving ground and weapon systems, and the missile trajectory measurement parameters to vividly exhibit a three-dimensional scene for the whole process of the missile proving ground test. The system can aid the experimentalist for observation, command, and decision-making.

Dim target detection from sea clutter is one of the difficult topics in ocean remote sensing application. By aiming at the shortcoming of false alarms when using track before detect (TBD) based on dynamic programming, a new discrimination method called statistics of direction histogram (SDH) is proposed, which is based on different features of trajectories between the true target and false one. Moreover, a new series of discrimination schemes of SDH and Local Extreme Value method (LEV) are studied and applied to simulate the actually measured radar data. The results show that the given discrimination is effective to reduce false alarms during dim targets detection.

A new HBC derivative HBC-C17containing 6 odd-carbon alkyl chains surrounding the hexabenzocoronene core was synthesized, and investigated as discotic liquid crystal along with HBC-C13and HBC-C15. The thermal behaviors have been investigated by using differential scanning calorimetry (DSC). And mesomorphic phase behavior of HBC-C17was observed by polarizing optical microscopy (POM). A remarkable variation in the phase transition temperatures was observed for these three HBC derivatives (HBC-C13, HBC-C15and HBC-C17). Moreover, the mesomorphism of these HBC derivatives can be compared with HBC-C12, HBC-C14and other HBCs with even carbon alkyl chains, meanwhile the relationship between the length of substitutes and thermal properties of HBCs is also studied.

A novel dibromo-substituted HBC derivative, whose side chains contains oxygen heteroatoms, has been successfully synthesized by Diels-Alder reaction of asymmetric synthesis. It possesses bromo-functional groups to provide possibility to further synthesize more complex HBC derivatives. The final compound’s structure has been confirmed by1HNMR,13CNMR and MALDI-TOF mass spectrometry.

A hexa-peri-hexabenzocoronene (HBC) derivative, substituted at periphery by six swallow-tailed alkyl chains containing ether linkages, has been synthesized. Its thermal properties and self-organization were investigated using differential scanning calorimetry (DSC) and polarized optical microscopy (POM). Results showed that the peripheral side chains substituted to the aromatic core could lead the HBC to a dramatically lowered isotropization temperature compared with those reported previously, allowing thermal processing at practical temperatures.