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The Silk Road is a land artery connecting China and the West, an important passage for East-West trade, and glass products are one of the treasures of early exchanges. Due to different production techniques, the composition and performance of Eastern and Western glass are often very different, but the identification of glass has always been a problem in ancient times. Aiming at the analysis of the composition and source of ancient glass products, this paper designs a mathematical model to avoid duplication of work. Based on the data, this paper calculates the classification rules of the main components of high potassium glass, lead-barium glass; and by selecting the appropriate chemical components as the subcomponents for each category, the specific division methods and division results are given, and the rationality and sensitivity of the classification results are analyzed. And the chemical composition of the unknown category of glass artifacts is identified by the model to identify the type they belong to, and the sensitivity of the classification results is analyzed.

Bismuth oxyhalide (Bi-O-X) is a group of layered semiconductors, which are promising candidates for photocatalysis due to their inherent internal electric field and adjustable band gap through comp...

Oxygen evolution reaction (OER) is the bottleneck reaction of the overall water splitting process despite the intensive research in the past decades. Efficient yet stable low-cost OER catalysts have been widely explored but further improvement is still highly demanded. Herein, a type of hybrid OER catalyst was prepared by the growth of CoFe-LDH (layered double hydroxide) on the surface of Ti3C2 MXene nanosheets, which exhibits superior OER performance than the state-of-the-art RuO2. The enhancement of the OER performance could be attributed to the combination of oxygen-breaking ability of CoFe-LDH and metallic conductivity of Ti3C2 MXene substrate. Meanwhile, the direct growth of CoFe-LDH on the hydroxyl-rich surface of MXene effectively prevents itself from aggregation, exposing more CoFe-LDH edge active sites. What's more important is that the intimate interface between CoFe-LDH and Ti3C2 MXene brings in efficient charge transfer and oxygen activation, which is supported by the DFT calculation results. The direct growth of CoFe-LDH on MXene endows the insulating LDH with metallic features with the O 2p states become distributed above the Fermi level which is mediated by the possible anionic redox process. This work demonstrates the great potential of MXene-based hybrid nanostructure for energy conversion applications.

One of the major hurdles of nickel-rich cathode materials for lithium-ion batteries is the low cycling stability, especially at high temperature and high voltage, originating from severe structural degradation, which makes this class of cathode less practical. Herein, we compared the effect of single and dual ions on electrochemical performance of high nickel (LiNi0.88Mn0.03Co0.09O2, NMC) cathode material in different temperatures and voltage ranges. The addition of a few amounts of tantalum (0.2 wt%) and boron (0.05 wt%) lead to improved electrochemical performance. The co-modified LiNi0.88Mn0.03Co0.09O2 displays an initial discharge capacity of 234.9 mAh/g at 0.1 C and retained 208 mAh/g at 1 C after 100 cycles at 45 °C, which corresponds to a capacity retention of 88.5%, compared to the initial discharge capacity of 234.1 mAh/g and retained capacity of 200.5 mAh/g (85.6%). The enhanced capacity retention is attributed to the synergetic effect of foreign elements by acting as a surface structural stabilizer without sacrificing specific capacity.

Nickel-rich cathode materials are increasingly being applied in commercial lithium-ion batteries to realize higher specific capacity as well as improved energy density. However, low structural stability and rapid capacity decay at high voltage and temperature hinder their rapid large-scale application. Herein, a wet chemical method followed by a post-annealing process is utilized to realize the surface coating of tantalum oxide on LiNi0.88Mn0.03Co0.09O2, and the electrochemical performance is improved. The modified LiNi0.88Mn0.03Co0.09O2 displays an initial discharge capacity of ∼ 233 mAh/g at 0.1 C and 174 mAh/g at 1 C after 150 cycles in the voltage range of 3.0 V–4.4 V at 45 °C, and it also exhibits an enhanced rate capability with 118 mAh/g at 5 C. The excellent performance is due to the introduction of tantalum oxide as a stable and functional layer to protect the surface of LiNi0.88Mn0.03Co0.09O2, and the surface side reactions and cation mixing are suppressed at the same time without hampering the charge transfer kinetics.

Porous niobium oxide nanowires synthesized via a solvothermal method exhibited decreased bandgap, enhanced light absorption and reduced charge-recombination rate. The porous Nb2O5 nanowires showed increased performance for the photocatalytic H2 evolution and photodegradation of rhodamine B, as compared to their solid counterparts, which could be ascribed to the peculiar porous nanostructure.

This paper presents a comprehensive investigation on the effects of tool and turning parameters on surface integrity and fatigue behavior in turning γ-TiAl alloy. The wear of inserts surface, cutting forces, and surface roughness were studied to optimize PVD-coated carbide inserts. Surface topography, residual stresses, microhardness, and microstructure were analyzed to characterize the surfaces layer under different turning parameters. Surface integrity and fatigue life tests of γ-TiAl alloy were conducted under turning and turning-polishing processes. The results show that compared to CNMG120412-MF4, CNMG120408-SM is more suitable because it obtained low cutting force, surface roughness, and tool wear. With increasing the cutting speed and depth, the depths of the compressive residual stress layer, hardening layer, and plastic deformation layer increased. For turning and turning-polishing specimens, the compressive residual stress was relaxed by less than 20%–30% after 107 cycles. The fatigue life of a turning-polishing specimen with Ra = 0.15 µm has increased 3 times from that of a turning specimen with Ra = 0.43 µm. Keywords: Fatigue behavior, Microhardness, Residual stress, Surface roughness, γ-TiAl alloy, Tool wear

Bismuth oxyhalide (Bi-O-X) is a group of layered semiconductors, which are promising candidates for photocatalysis due to their inherent internal electric field and adjustable band gap through composition and morphology control. Bismuth-rich Bi-O-X has improved stability and advantageous band structure compared to those of Bi-O-X and hence has attracted an increasing amount of research interest. In this work, ultrathin nanotubes of Bi

// Jiannan Lin 1 and Tieliu Shi 1 1 The Center for Bioinformatics and Computational Biology, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China Correspondence to: Tieliu Shi, email: tieliushi01@gmail.com Keywords: A to G mutation, mutational mechanism, error-prone DNA polymerase, oxidative stress, RAS mutation Received: August 29, 2016 Accepted: October 29, 2016 Published: November 11, 2016 ABSTRACT Mutational processes for A→G mutations in tumors are not well understood. To uncover the mutational mechanisms, we analyzed molecular profiles of more than 9,000 tumor samples from The Cancer Genome Atlas (TCGA). The present study found that error-prone DNA polymerases were involved in stomach tumors with high fraction of A→G mutations. High levels of apoptosis in kidney cancers and high levels of energy metabolism in thyroid cancers increased A→G mutation rate, which was associated with high oxidative stress. We also found that the frequencies of RAS gene mutations were increased in thyroid cancers with high level of energy metabolism because of high-frequency A→G mutations.

Chinese hamster ovary (CHO) cells are frequently used for the production of recombinant proteins for therapeutical applications. However, the recombinant protein expression level of CHO cells may reduce during long-term culture. The physiological changes related to the stability of expression were not well understood. In this study, we performed a series of genetic analysis on stable and unstable clonal derived populations. Transcriptome analysis revealed that a large number of differentially expressed genes (>100) were identified in the unstable population between early and late generations, while only a few differentially expressed genes were found in the stable population, suggesting that the gene expression change is related to the instability of recombinant protein production. On the other hand, no significant differences were found in promoter methylation or gene copy numbers in the unstable population. Taken together, our data help better understand the molecular mechanism underlying the stability of recombinant protein production in CHO cells.

Photocatalytic nitrogen fixation has been burgeoning since the 20th century because the conventional Haber–Bosch process is quite energy-intensive, so other sustainable alternatives are highly required. This work uses a facile way to synthesize ultrasmall metal ruthenium on TiO2(P25) for photocatalytic nitrogen fixation at ambient temperature and pressure. The metal ruthenium is 2–3 nm in size and evenly dispersed over TiO2(P25). Both Indophenol method and ion chromatography are used to detect the ammonia yield, and possible mechanism is also proposed.

In this work, we report RuO2-loaded TiO2–MXene hybrid nanostructure as a promising photocatalyst possessing remarkable activity for photocatalytic nitrogen fixation in water at room temperature. The MXene was synthesized by HF etching of the precursor Ti3AlC2 and used as the substrate for the growth of RuO2 nanoparticles and TiO2 through a hydrothermal reaction. The benign activity is mainly attributed to the synergetic effect among MXene, TiO2, and RuO2 in photocatalytic ammonia synthesis by combining light harvesting and nitrogen activation.

Previous phylogenetic analyses have led to incongruent evolutionary relationships between tree shrews and other suborders of Euarchontoglires. What caused the incongruence remains elusive. In this study, we identified 6845 orthologous genes between seventeen placental mammals. Tree shrews and Primates were monophyletic in the phylogenetic trees derived from the first or/and second codon positions whereas tree shrews and Glires formed a monophyly in the trees derived from the third or all codon positions. The same topology was obtained in the phylogeny inference using the slowly and fast evolving genes, respectively. This incongruence was likely attributed to the fast substitution rate in tree shrews and Glires. Notably, sequence GC content only was not informative to resolve the controversial phylogenetic relationships between tree shrews, Glires, and Primates. Finally, estimation in the confidence of the tree selection strongly supported the phylogenetic affiliation of tree shrews to Primates as a monophyly.

Nucleosome positioning and histone modification play a critical role in gene regulation, but their role during reprogramming has not been fully elucidated. Here, we determined the genome-wide nucleosome coverage and histone methylation occupancy in mouse embryonic fibroblasts (MEFs), induced pluripotent stem cells (iPSCs) and pre-iPSCs. We found that nucleosome occupancy increases in promoter regions and decreases in intergenic regions in pre-iPSCs, then recovers to an intermediate level in iPSCs. We also found that nucleosomes in pre-iPSCs are much more phased than those in MEFs and iPSCs. During reprogramming, nucleosome reorganization and histone methylation around transcription start sites (TSSs) are highly coordinated with distinctively transcriptional activities. Bivalent promoters gradually increase, while repressive promoters gradually decrease. High CpG (HCG) promoters of active genes are characterized by nucleosome depletion at TSSs, while low CpG (LCG) promoters exhibit the opposite characteristics. In addition, we show that vitamin C (VC) promotes reorganizations of canonical, H3K4me3- and H3K27me3-modified nucleosomes on specific genes during transition from pre-iPSCs to iPSCs. These data demonstrate that pre-iPSCs have a more open and phased chromatin architecture than that of MEFs and iPSCs. Finally, this study reveals the dynamics and critical roles of nucleosome positioning and chromatin organization in gene regulation during reprogramming.

An increased incidence of cardiovascular events and sudden death occurs after an earthquake. However, the mechanism underlying this is not clear. Previous studies attributed this phenomenon to earthquake-induced elevation of sympathetic activity. This study investigated the acute cardiovascular effects of the Wenchuan earthquake on hypertensive or suspected hypertensive patients. We studied the role of earthquake-induced changes in blood pressure and heart rate in the occurrence of post-earthquake cardiovascular events. This study included 11 patients who were undergoing ambulatory blood pressure monitoring when the Wenchuan earthquake occurred. Trends in blood pressure and heart rate were analyzed, and blood pressure variability (BPV) data were obtained. The mean post-earthquake blood pressure rose rapidly from 125.8+/-17.3/72.1+/-11.9 to 150.5+/-20.3/98+/-10.6 mm Hg (average time of first measurement was 13.8+/-6.3 min after the first tremor), and blood pressure remained high until 6 h after the earthquake. Nighttime blood pressure declined to the mean pre-earthquake daytime levels. The mean daytime blood pressure after the earthquake was greater than the pre-earthquake daytime mean (systolic blood pressure: 138.9+/-14.6 vs. 129.5+/-13.6 mm Hg, P=0.009; diastolic blood pressure (DBP): 81.8+/-13.1 vs. 76.9+/-11.9 mm Hg, P=0.011). Pre- and post-earthquake BPV differed among individuals, but circadian variation was absent in all cases and nightly decreases were less than 10%. These data strongly suggest that significant post-earthquake elevation of blood pressure and abnormal circadian variation of blood pressure are related to the occurrence of post-earthquake cardiovascular events.

Prevention and treatment of geological hazards is important for the sustainable development of human society. Surface geological hazards alone caused direct economic losses of ¥3.47 billion, with 768 deaths and 785 injuries in Guangdong Province, South China, from 1994 to 2005. The major factors causing geological hazards can be categorised into three types: geo-environmental, climatic-meteorological and human activity. Accompanied by rapid economic development and population growth, human activities can cause geological hazards that are as serious as those caused by natural factors. The authors propose some suggestions for prevention and treatment of geological hazards to achieve sustainable development on the Chinese coast.