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The Sumochaganaobao (Sucha) deposit in Siziwang Banner, Inner Mongolia is considered to be the largest single fluorite deposit known in the world, and apart from a small amount of localized pyritization, no metal mineralization has been found for many years. In recent years larger scale Pb–Zn polymetallic veins have been uncovered which indicates the potential for large scale metal mineralization in this deposit in addition to fluorite ore. Laser-ablation inductively coupled mass spectroscopy (LA-ICPMS) technique is used to investigate the distribution and substitution of trace elements in sphalerite and pyrite. The confirming results show that sphalerite is mainly rich in Fe, Mn, Cd, Co, Ni, Cu, In and poor in Sb and Mo. Pyrite is mainly rich in Ni, As, Sb, Cr, Mn, Co, Cu, Sn, Pb, Tl, Se and poor in Cd, Au, Ga, In, Bi. Iron, Mn, Cd, In, Co, Ni, Cr, Bi and Cu in sphalerite and Ni, As, Sb, Mn, Co, Cu, Ni, As, Pb, Tl, and Se in pyrite are generally lattice-bounded, while Pb and Cd present both in solid solution and/or discrete micro/nano-inclusions. The elemental contents of Fe, Mn and In and elemental ratios of Ga/In, Zn/Cd and In/Ge illustrate the trace elemental characteristics of medium temperature sphalerite. The trace elements in pyrite are diverse along with both relatively high-temperature elements (e.g. Ni, Co, Sn, Cu, etc.) and relatively low-temperature elements (e.g. As, Sb, Pb, etc.). The Co/Ni ratios indicate that the pyrite formed under a low-temperature condition. The crystallisation from sphalerite to pyrite may have undergone a relatively rapid cooling process from medium to low temperature. The characteristics of sphalerite and trace elements indicate that the genesis of this deposit is closest to that of SEDEX type deposit. Considering the marine sedimentation or marine volcanic eruption, jasperite development, clastic rock hosting, layered ore-body, and the geochemical characteristics of trace elements of this deposit, the newly discovered Pb–Zn vein should belong to the SEDEX type. • The Pb–Zn polymetallic veins were found firstly in the world known fluorite deposit. • The concentrations of trace elements were detected on LA-ICPMS technique firstly in this deposit. • The mineralization temperature and ore genesis of lead-zinc vein were constrained. [ABSTRACT FROM AUTHOR]

Abstract Nanofluidic channels with a depth of ∼100 nm were developed as a leak element, where the fluidic channels were etched on silicon wafer by reactive ion etching and then enclosed by direct silicon bonding. Instead of the Torr-seal gluing method, a tight lamination between the chip and the vacuum flange was achieved using indium gasket sealing, eliminating the influence of Torr-seal outgassing. Two leak elements with different amount of parallel channels were fabricated and their values were characterized by the difference method. The results demonstrate that the conductance of the leak elements behave in reasonable agreement with their theoretically calculated conductance with relative errors of approximately 4.9% and 42.7%, respectively. The gas flow through these leak elements realizes molecular flow at pressures ranging from high vacuum up to 105 Pa for helium, argon, and nitrogen and can therefore be used as predictable leak elements for any gas. Highlights • Nanofluidic channels with a depth of ∼100 nm are developed as a leak element and enclosed by direct silicon bonding. • A new leak element is packaged with an indium gasket to eliminate the influence of Torr-seal outgassing. • The conductance of the two leak elements is measured based on difference method. • The gas flow through the leak element is molecular flow range up to 105 Pa for helium, argon, and nitrogen. [ABSTRACT FROM AUTHOR]

Wax gourd (2n = 2 x = 24) is an important vegetable species in Cucurbitaceae . Because it can be stored for a very long period of time, it plays an important role in ensuring the annual supply and regulating off-season supply of the vegetables. However, the availability of genetic information about wax gourd is limited. This study aimed to identify the useful genetic information for wax gourd. The conserved domains of reverse transcriptase (RT) genes of Ty1- copia retrotransposons were isolated from the genome of wax gourd using degenerate oligonucleotide primers. A total of twenty eight RT sequences were obtained, which showed high heterogeneity with the similarity ranging from 47.5% to 94.3%. Sixteen (57.1%) of them were found to be defective, being disrupted by stop codons and/or frameshift mutations. These 28 sequences were divided into five subfamilies. The comparative phylogenetic analysis with other Cucurbitaceae species from GenBank database showed that most retrotransposons derived from the same genus tended to cluster together, although there were a few exceptions. These results indicate that both vertical transmission and horizontal transmission are the sources of Ty1- copia retrotransposons in wax gourd. Fluorescent in situ hybridization (FISH) with Ty1- copia retrotransposon sequences as probes revealed that this kind of retrotransposons had a dispersed genomic organization, physically distributed among all the chromosomes of wax gourd, with clusters in the heterochromatin regions. This is the first report of Ty1- copia retrotransposons in wax gourd, which would be helpful for our understanding about the organization and evolutions of wax gourd genome and also provide valuable information for our utilization of wax gourd retrotransposons. [ABSTRACT FROM AUTHOR]

Abstract: Proline potassium salt was successfully firstly used to catalyze the Friedlander annulation toward the synthesis of 4-trifluoromethyl-substituted quinolines from the substituted 2-trifluoroacetyl anilines and variety carbonyl compounds under mild conditions in good to excellent yields. This catalyst provides several advantages, such as shorter reaction time, high regioselectivity, functional group tolerance, and broad substrate scope. [Copyright &y& Elsevier]