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The Jiangnan Orogen in the South China Block collapsed rapidly after the Neoproterozoic assembly of the Yangtze and Cathaysia blocks. Extensional collapse of orogens is generally triggered by post-orogenic extension and/or continental rifting. Detrital zircon U-Pb geochronology and trace elements geochemistry was conducted on sedimentary rocks across the Neoproterozoic angular unconformity in the Northwestern Zhejiang Basin. Detrital zircon U-Pb ages indicate that the Chentangwu Formation (upper Pingshui Group) and the Heshangzhen Group were deposited from 840 to 820 Ma and 810-780 Ma, respectively. The Trace elements geochemistry of early Neoproterozoic detrital zircons suggests that the source rocks of the Chentangwu Formation were derived from continental arcs and oceanic islands whereas those of the Heshangzhen Group (the Luojiamen and the Hongchicun formations) were likely related to continental arcs, oceanic islands and mid-oceanic ridges. This study reveals that the Chentangwu Formation was probably deposited in a Neoproterozoic back-arc basin which was filled by sediments from the Cathaysia Block, the Shuangxiwu Arc, and the Jiangnan Orogen. The source regions of the Hongchicun formations outcrops in the eastern and western Northwestern Zhejiang Basin are the Cathaysia Block and the Jiangnan Orogen, respectively. However, the Shangshu Formation in the west has the same source regions as the underlying Hongchicun Formation in the east. The variations in thickness and source rocks exhibited by the Hongchicun formations in the west and east are controlled by normal faulting along the Dexing-Huangshan fault zone, which is the western boundary fault of the Northwestern Zhejiang Basin. The growth fault resulted in the formation of a ridged rollover anticline in the middle of the Northwestern Zhejiang Basin and prevented ∼810 Ma zircons from being transported to the west during deposition of the Hongchicun Formation. Comprehensive analysis reveals that the extensional collapse of the Jiangnan Orogen resulted from 810 to 780 Ma post-orogenic extension.

Many factors, including improper maintenance and material aging, may lead to the occurrence of defects during the operation of the various functions of buildings. Building defect information is normally stored in a discrete and unstructured way, and for this reason, building a case-based reasoning framework regarding building defects to enhance the level of building maintenance management has become an important field in the related research. At present, there is limited research available on the integration of geometric data models that are built by means of scanning and multi-attribute selection strategies. This study proposes an integrated information management framework for superficial defects in buildings, which is compatible with a point clouds model as a central data source. It features the attributes of defects used in multi-criteria decision analysis. A CBR (case-based reasoning) approach that considers case-based distance is used to enhance the performance of similarity calculations and case retrieval. A case-based distance model is utilized for the data processing stage and concentrates on a smaller case set that contains best alternatives. The potential benefit offered by this approach is that more efficient results can be obtained from classified cases during the retrieval phase process. A comparison of a CBR query with ungrouped sample data is performed to establish patterns to verify the effectiveness of the calculation method of determining case similarity, which is supported by the pre-processing of classified information about the building defects. The analytical results show that the proposed method performs well in solving the multi-attribute classification of building defects and avoiding ambiguous answers retrieved from unrelated subsets. This approach might be capable of investigating the practical problems involved in building maintenance in the AEC domains.

Background Few studies are available on the mechanism of intestinal dysfunction in newborn piglets with intrauterine growth restriction (IUGR). This work aimed to study the mechanism of jejunum dysfunction in IUGR newborn piglets through RNA-seq and improve their performance by dimethylglycine sodium salt (DMG-Na) supplementation after weaning. Methods In total, 13 normal birth weight (NBW) newborn piglets and 23 IUGR newborn piglets were obtained. Among them, 3 NBW and 3 IUGR newborn piglets were selected and stunned by electric shock after birth without suckling and collected the jejunum samples for RNA-sEq. After weaning at 21 days, they were randomly assigned to 3 groups (n = 10): NBW weaned piglets fed with common basal diets (N); IUGR weaned piglets fed with common basal diets (I); IUGR weaned piglets fed with common basal diets plus 0.1% DMG-Na (ID). All piglets are slaughtered at 49 days of age to collect serum and jejunum samples. Results The hub genes, including ATP8, C11orf86, CDKN1C, DDX58. HPX, INHBB, LECT2, ND1, NFIX, PRDM5, PSD3, SCD, and ZNF770, were found from the data analyzed by RNA-seq and WGCNA. Interestingly, we found ATP8 was the most significantly changed gene, which was crucial in maintaining mitochondrial function. After weaning, the growth performance of ID group was improved (P P P

Sex reversal, representing an extraordinary sexual plasticity during the life cycle, not only triggers reproduction in animals but also affects reproductive and endocrine system-related diseases and cancers in humans. Sex reversal has been broadly reported in animals, however, an integrated resource hub of sex reversal information is still lacking. Here, we constructed a comprehensive database named ASER (Animal Sex Reversal) by integrating sex reversal-related data of 18 species from teleostei to mammals. We systematically collected 40,018 published papers and mined the sex reversal-associated genes (SRGs), including their regulatory networks, from 1611 core papers. We annotated homologous genes and computed conservation scores for whole genomes across the 18 species. Furthermore, we collected available RNA-seq datasets and investigated the expression dynamics of SRGs during sex reversal or sex determination processes. In addition, we manually annotated 550 in situ hybridization (ISH), fluorescencein situhybridization (FISH), and immunohistochemistry (IHC) images of SRGs from the literature and described their spatial expression in the gonads. Collectively, ASER provides a unique and integrated resource for researchers to query and reuse organized data to explore the mechanisms and applications of SRGs in animal breeding and human health. The ASER database is publicly available at http://aser.ihb.ac.cn/.

T-cell recognition of somatic mutation-derived cancer neoepitopes can lead to tumor regression. Due to the difficulty to identify effective neoepitopes, constructing a database for sharing experimentally validated cancer neoantigens will be beneficial to precise cancer immunotherapy. Meanwhile, the routine neoepitope prediction in silico is important but laborious for clinical use. Here we present NEPdb, a database that contains more than 17,000 validated human immunogenic neoantigens and ineffective neoepitopes within human leukocyte antigens (HLAs) via curating published literature with our semi-automatic pipeline. Furthermore, NEPdb also provides pan-cancer level predicted HLA-I neoepitopes derived from 16,745 shared cancer somatic mutations, using state-of-the-art predictors. With a well-designed search engine and visualization modes, this database would enhance the efficiency of neoantigen-based cancer studies and treatments. NEPdb is freely available at http://nep.whu.edu.cn/.

Background Coronary artery spasm (CAS) and stress cardiomyopathy (SC) have different characteristic clinical manifestations in the case of suspicious myocardial infarction with nonobstructive coronary arteries. Established recurrence rates of both conditions have been reported, however, alternate recurrent CAS and SC in the same individual have not been described. Case presentation A 59-year-old man suffered from atypical chest pain in the first episode, acute heart attack in the second and third episodes (totally 3 times over a period of approximately 5 years). During the first episode, he visited our hospital with mild paroxysmal chest pain without obvious inducement for approximately 2 years. He was underdiagnosed at that time without other obvious findings except the poor R wave progression in V1–3 leads revealed in electrocardiogram. At 4 months after the first episode, he suffered from a heart attack (the second episode) and was diagnosed with SC based on the coronary angiography (CAG) and left ventriculography findings of nonobstructive coronary arteries combined with a classic apical ballooning shape. At 31 months after the second episode, he suffered another heart attack (the third episode) and was diagnosed with CAS based on the CAG results of recoverable severe multivessel stenoses. During the episodes, partial reversible nature of apical hypokinesis was observed in echocardiogram. In retrospect, the patient suffered silent CAS in the first episode, SC in the second episode, and severe multivessel CAS in the third episode. Conclusion The unusual presentations observed in this case have not been reported. This case suggests that cardiologists should be aware of the possibility of alternate recurrent CAS and SC in the same individual. Provocative tests for spasm and cardiac magnetic resonance imaging might help gain more insights into this issue.

The objective of this paper is to optimize a design of a slotted horseshoe type axial magnetic field (AMF) contacts, which is used for 126 kV vacuum interrupters (VIs). Through Box-Behnken Design method and finite element calculation, the AMF characteristics and loop resistance of the contact system with seven design parameters were obtained. Seven contact parameters included the outer diameter of the iron plates ( $D$ ), the inner diameter of the iron plates ( $d$ ), the height of iron plates ( $h$ ), the slot angle of iron plates ( $\theta$ ), length of the slope on iron plates ( $s$ ), the height of chamfer on the tip of iron plates ( $h_{t}$ ), the height of chamfer on the back side of iron plates ( $l$ ). Three optimization objectives were chosen as follows: the maximum axial magnetic flux density at current peak ( $B$ ), the maximum area of “effective region” ( $S$ ), and the minimum loop resistance of contact system ( $R$ ). Based on the simulation results, the equations of AMF characteristics and loop resistance of the contact system were determined. Then the AMF characteristics were optimized by multi-objective optimization. The optimum values of $D,\ d,\ h,\ \theta,\ s,\ h_{t}$ , and $l$ were determined as 92 mm, 72 mm, 59 mm, 104.6°, 70 mm, 0 and 20 mm, respectively, which achieved the optimal performance. The optimized $B,\ S$ and $R$ were 186.2 mT, 2766.9 mm2, and $7.7\ \mu\Omega$ , respectively. After optimization, $B$ increased 45.47%, $S$ increased 81.28%, $R$ decreased 54.50%.

CuCr contact materials are dominant in vacuum circuit breakers. It is interesting to find superior material than the CuCr. Mo has a higher melting point and boiling point, so that it becomes a potential candidate to replace Cr. The objective of this paper is to compare the distribution characteristics of cathode spots (CSs) on Cr and Mo cathodes in drawn vacuum arcs with an external axial magnetic field (AMF). The experiments were carried out in a demountable vacuum chamber. A pair of Helmholtz coils were set in the chamber to supply a uniform AMF. The arc current in the experiments was 10 kA (rms) at 44.5 Hz. The AMF flux density were 75, 133, and 187 mT, respectively. The experimental results showed that, under the three levels of AMF, the constriction of the CSs of Mo cathode was more serious than those of Cr cathode, which would lead to the more severe erosion of Mo cathode. Especially, before current zero, much cathode spot plasma particles jetted from the Mo cathode contact, while that of Cr cathode was much less. Therefore, Mo could not replace Cr for vacuum circuit breakers, indicating that the thermal parameters could not be used alone as a criterion for selecting contact materials.

Tuberculosis (TB), one major threat to humans, can infect one third of the worldwide population, and cause more than one million deaths each year. This study aimed to identify the effective diagnosis and therapy biomarkers of TB. Hence, we analyzed two microarray datasets (GSE54992 and GSE62525) derived from the Gene Expression Omnibus (GEO) database to find the differentially expressed genes (DEGs) of peripheral blood mononuclear cell (PBMC) between TB patients and healthy specimens. Functional and pathway enrichment of the DEGs were analyzed by Metascape database. Protein-protein interaction (PPI) network among the DEGs were constructed by STRING databases and visualized in Cytoscape software. The related transcription factors regulatory network of the DEGs was also constructed. A total of 190 DEGs including 36 up-regulated genes and 154 down-regulated genes were obtained in TB samples. Gene functional enrichment analysis showed that these DEGs were enriched in T cell activation, chemotaxis, leukocyte activation involved in immune response, cytokine secretion, head development, etc. The top six hub genes (namely, LRRK2, FYN, GART, CCR7, CXCR5, and FASLG) and two significant modules were got from PPI network of DEGs. Vital transcriptional factors, such as FoxC1 and GATA2, were discovered with close interaction with these six hub DEGs. By systemic bioinformatic analysis, many DEGs associated with TB were screened, and these identified hub DEGs may be potential biomarkers for diagnosis and treatment of TB in the future.

Pilot-scale floating constructed wetlands (FCWs) under varying influent salinities were implemented, and the effects of influent salinity on pollutant removal efficiency (RE) and macrophyte species selection were identified. The results suggest that a salinity increase generally decreased pollutant REs, while some macrophytes, such as Iris pseudacorus, could effectively resist this decrease. The average coefficients of variation between macrophyte species in REs of chemical oxygen demand, ammonium nitrogen, nitrate nitrogen and total phosphorus increased from 28.6% at low salinity to 91.3% at high salinity, which suggests the greater importance of macrophyte selection under high salinity. With an increase in salinity, the rhizosphere bacterial community showed convergent evolution or convergence followed by slight divergent evolution between macrophyte species, while the importance of macrophyte parameter selection in characterizing pollutant REs decreased. Therefore, influent salinity is a key factor to consider in macrophyte selection and application, especially in FCWs without soil.

Background Receptor tyrosine kinase AXL has been found to be highly expressed in osteosarcoma and positively associated with poor prognosis. There are tumor groups with high or low AXL expression, which had different capabilities of invading vessels and forming distal metastases. Exosome‐transmitted lncRNA may be transferred intercellularly to promote tumor cells’ proliferation and invasion. Methods Exosomes were detected by electron microscopy, particle size analysis, and western blotting. High‐throughput sequencing helped to find the highest differentially expressed lncRNA in AXL‐associated exosomes. Clone formation, wound healing, transwell assay, and xenograft model in nude mice were performed to evaluate cells’ proliferation, migration, and invasion in vitro and in vivo. Lentiviral transfection was used to up‐ or down‐regulate the lncRNA levels in cell lines. Luciferase reporter assay and RNA FISH etchelped to indicate the molecular mechanisms. The results in the cell lines were proved in the osteosarcoma tissues with clinical analysis. Results The exosomes derived from donor cells with high AXL expression could promote the proliferation and invasion and upregulate AXL expression of the receiver cells with low AXL. Linc00852 was the highest differentially expressed lncRNA in AXL‐associated exosomes and was also regulated by AXL expression. Although the mechanisms of linc00852 in nucleus were unrevealed, it could upregulate AXL expression partly by competitively binding to miR‐7‐5p. The AXL‐exosome‐linc00852‐AXL positive feedback loop might exist between the donor cells and the receiver cells. Clinically, linc00852 was significantly highly expressed in osteosarcoma tissues and positively associated with tumor volumes and metastases, which was also obviously related with AXL mRNA expression. Conclusion AXL‐associated exosomal linc00852 up‐regulated the proliferation, migration, and invasion of osteosarcoma cells, which would be considered as a new tumor biomarker and a special therapeutic target for osteosarcoma., Exosomal linc00852 promotes osteosarcoma migration and invasion by upregulating AXL. AXL‐associated exosomal linc00852 may be considered as a new tumor biomarker and a special therapeutic target for osteosarcoma.

To determine the pathogeny for the mass death in the golden pompano Trachinotus ovatus in Hainan, China, the potential pathogens (HAINUV01, HAINUV02, and HAINUV03) were isolated from the infected pompano. The infected fish showed swollen, hyperemic livers and spleens, yellowish effusion in the gut, and different degrees of ulcerations on the bases of dorsal and pelvic fins. HAINUV01 had the strongest virulence to the pompano with a lethal dose (LD50) of 14 days of 1.75 × 102 CFU/g fish by intraperitoneal (i.p.) injection. HAINUV01 was Gram-negative, straight rods, 2.37 ± 0.12 μm in length by 0.857 ± 0.003 μm width, with only one polar flagellum (4.78 ± 0.33 μm). Neighbor-joining phylogenetic analysis based on 16S rRNA, mreB, pyrH, recA and rpoA genes identified HAINUV01 as Vibrio ponticus. These findings provide direction for controlling V. ponticus-related disease occurrences in the future.

Segmenting a skeleton feature sequence into pose and motion feature segments can improve the effectiveness of key pose based human activity recognition. Nevertheless, the fixed number of atomic motions in feature segments results in the lost of temporal information, it makes the segmentation technique hardly suitable for all scenarios of feature sequences. To address this issue, this paper proposes a human activity recognition method using dynamic representation and matching of skeleton feature sequences based on the segmentation technique. In our method, a skeleton feature sequence is first segmented into key pose and atomic motion segments according to the potential differences. Afterwards, a learning strategy is proposed to select some frame sets with high confidence value, and we then extract series of poses (i.e., atomic motion series) with different numbers of poses from the learnt frame sets to represent motion feature segments, while a fixed number of centroids obtained by K -Means are used to represent pose feature segments. Finally, the shape dynamic time warping (shapeDTW) algorithm is utilized to measure the distance between the corresponding motion feature segments of two feature sequences. Comprehensive experiments are conducted on three public human activity datasets, and the results show that our method achieves superior performances in comparison with some state-of-the-art methods.

The images and videos captured in bad weather usually have low quality caused by reduced contrast and faded color. However, traditional techniques are not sufficient to solve the problems of halo artifacts and brightness distortion. In this paper, a multi-focus fusion method for single fog image restoration is proposed. Firstly, we estimate the global atmospheric light only in the sky regions to minimize interference from other regions. Secondly, we introduce a novel fast local Laplacian filtering with adaptive boundary constraint to optimize the transmission properly so as to reduce the halo artifacts. Finally, we remove the haze and produce a more natural effect on visual recovery by using a new multi-focus image fusion method. Experimental results show that the proposed method outperforms state-of-the-art haze removal methods in terms of efficiency and dehazing visual effect.

Object detection plays an important role in the underwater object recognition technology of sonar equipment. We propose a Novel quantum-inspired shuffled frog leaping algorithm (NQSFLA) to obtain more accurate detection results in this paper. The proposed NQSFLA adopts a fitness function combining intra-class difference with inter-class difference to evaluate the frog position more accurately and a new quantum evolution update strategy to improve the searching ability in the searching process. In order to avoid the disadvantages of Quantuminspired shuffled frog leaping algorithm (QSFLA), a fuzzy membership matrix with spatial information model is developed, which can remove isolated regions and further improve the detection accuracy. Segmentation, distribution and noise entropy (SDNE) model is also proposed to quantitatively evaluate the detection results. The detection results of the original sonar images demonstrate the effectiveness and adaptability of the proposed method.

CoB/ZIF-8 supported catalysts were successfully prepared using Co/Zn-ZIF-8 as the precursor by single-step reduction, which was applied in hydrogen release from the hydrolysis of NaBH4. Reducible Co ions of Co/Zn-ZIF-8 can be partially in-situ transformed into CoB by direct reduction, whereas ZIF-8 framework structure can be well preserved due to the resistance of Zn to reducing ambiences. Accordingly, CoB active components can be highly loaded onto ZIF-8 support to produce CoB/ZIF-8 catalysts. The texture evolution of Co/Zn-ZIF-8 during reduction was investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscope and nitrogen adsorption–desorption isotherms. Compared with the reduction of Co-ZIF-67, the framework structure of Co/Zn-ZIF-8 can be effectively preserved although Co ions of Co/Zn-ZIF-8 were partially reduced into cobalt-based alloy. In the hydrogen release from hydrolysis of NaBH4, CoB/ZIF-8 supported catalyst exhibits excellent catalytic activity. The effect of NaOH concentration, NaBH4 concentration and reaction temperature on hydrolysis reaction of NaBH4 was deeply studied based on this catalyst. Compared with other published catalysts, this catalyst exhibits relatively low activation energy of about 57.72 kJ mol−1.

Enrichment of bio-based platform compound ABE (acetone-butanol-ethanol) from extremely diluted raw medium is pivotal for the full utilization of ABE and selective conversion of them into value-added chemicals. Vapor permeation process through mixed matrix membranes (MMMs) demonstrates an energy-efficient solution to this challenge. Here, MMMs, by doping two-dimensional ZIF-L nanosheets with porous skeletons into an oleophilic matrix (poly-R-siloxane), were produced to synchronously enrich ABE from the simulated fermentation broth (total ABE of 3.0 wt% or lower, and composition of A: B: E = 3: 6: 1). The good compatibility of ZIF-L and polymer matrix renders MMMs with significantly improved flux and separation factor of organics over water. Typically, MMMs incorporating 5.0 wt% of ZIF-L fillers contribute to an increase of 72.3% and 106% in liquid flux and butanol/water separation factor, respectively, when compared with the pure polymer membranes. Through ZIF-L based MMMs, the water content in the permeant is controlled below 30 wt%, which is a prerequisite for utilization of ABE in the real bio-refinery industry.

Social risks posed by infrastructure projects can seriously threaten the successful implementation of the project and the social stability of the city more broadly. There is thus a need to better understand how social risks are originated and developed so that decision makers can better manage them. In this study, nine social risk factors and twelve stakeholders associated with these social risks are identified based on a literature review and 43 infrastructure cases. Social networks among these stakeholders in social risks are formalized using social network analysis (SNA). To reflect the evolution of social risk evolution more accurately, the behaviors of the general public in five different behavior states (appeal, pussyfoot, probably protest, protest, withdraw) are simulated by means of agent-based modeling (ABM), with the developed model being applied to a real-world case for demonstration purposes. Two scenarios are evaluated in terms of the communication effects and the risk governance effects in the evolution of social risk. This SNA-based ABM model can be a powerful tool for testing the response effectiveness of different risk mitigation strategies with respect to the impacts of the social risk development process, as well as for supporting social risk management decision making in infrastructure projects.

Ethanol protocol, two-step protocol and enzymatic extraction were used to extract prolamins from seven kidney beans (P. vulgaris L.) compared with Osborne protocol. 70-80% (v/v) ethanol concentrations were beneficial to the extraction, and two-step protocol was conducive to higher prolamin content. Varied protein subunits were observed in electrophoresis profiles, and further differences in composition were identified by LC-MS/MS while potential functions were annotated. Stronger hydrophobicity was found with prolamins enrichment from light speckled kidney bean (LSKB), black speckled kidney bean (BSKB), and red kidney bean (RKB), which was negative correlation with α-helix content based on the principal component analysis (PCA). The crude prolamins from the two kinds of white kidney beans possessed higher sulfhydryl and exhibited better water holding capacity (WHC), while higher oil absorption capacity (OAC) was observed in LSKB, BSKB, and RKB. Compared with zein, kidney bean prolamins could be used as food packaging materials due to hydrophobicity.

Because the probiotic and growth characteristics of probiotics are strain-specific features, it is crucial to be able to distinguish the probiotic strains from the other strains in the same species. To rapidly identify Lactobacillus rhamnosus at the strain level through PCR, a method for searching for several strain-specific sequences in the genome of a strain was investigated. The whole genomes of L. rhamnosus hsryfm 1301 and L. rhamnosus LV108 were sequenced, and gene family analysis was performed with using L. rhamnosus GG and L. rhamnosus Lc705 as reference strains. Thirty-one and 19 strain-specific open reading frames (ORFs) were found in L. rhamnosus hsryfm 1301 and L. rhamnosus LV108, respectively. Thus, strain-specific primer pairs could be designed in a more rational and controllable manner. Concatenation of several strain-specific primer pairs designed from the strain-specific ORFs (and their adjacent regions) were able to distinguish L. rhamnosus LV108 (primer pairs V2, V4, V5, and V9) or L. rhamnosus hsryfm 1301 (primer pairs H1, H2, H3, and H4) from 12 other L. rhamnosus strains. This strain-specific identification method was determined to be accurate, rapid, economical, reproducible and easy to perform.

The aim of this study is to investigate the effects of a nitric oxide (NO) donor S-nitrosoglutathione (GSNO) on the metabolism and improvement of preservation quality in apheresis platelets. A GSNO solution with a certain concentration was added into fresh apheresis platelets, and the parameters associated with platelet morphology, metabolism and function were temporally monitored for 7 days. The results showed that the NO level in GSNO group were remarkably higher than those in the control group during the whole storage stage. No significant morphology or function difference was observed between the control and GSNO groups such as Platelet count, platelet distribution width, mean platelet volume and mitochondrial metabolic activity. But in metabolism there are something differences from morphology data: pCO2, pO2, cHCO3 − were also found to have no clear difference between the control and GSNO groups; the lactic acid content, sugar consumption and Lactate dehydrogenase activity in the GSNO group were lower than that in the control group at some time point; and pH values in the GSNO group were higher than the control group. Our study discovered that the NO donor GSNO can reduce the metabolism and maintain the cellular characteristics of platelets in vitro during the platelet storage period.

To investigate the role of Fe ions for oxygen evolution reaction, a series of BaZrxFe1-xO3-δ (0 ≤ x ≤ 0.2) perovskite oxides were synthesized and systematically evaluated as electrocatalysts. The OER activity of cubic BaZrxFe1-xO3-δ (0.05 ≤ x ≤ 0.2) is higher than that of the parent BaFeO3-δ with a monoclinic structure and close to that of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), indicating cubic perovskite structure is favorable to the OER, and Fe ions are active for the reaction. Moreover, for cubic BaZr0.15Fe0.85O3-δ samples, the OER performance is closely related to the ratio of Fe4+ to Fe3+, which was tuned by treating BaZr0.15Fe0.85O3-δ powders at 500 °C for 5 h at different atmospheres, such as O2, air, Ar and 5% H2/Ar mixture.

Lipids and lipases/esterases are essential for Mycobacterium tuberculosis (Mtb) survival and persistence, even virulence. Mycobacterium tuberculosis H37Rv Rv1076 (LipU), a member of lipase family, is homologous to the human Hormone Sensitive Lipase (HSL) based on the presence of conserved motif ‘GXSXG’. To define the enzymatic characteristics of rv1076 , the gene was cloned, and expressed in Escherichia coli . The protein was purified for enzymatic characterization. LipU showed high specific activity for the hydrolysis of short carbon chain substrates with optimal activity at 40 °C/pH 8.0 and stability at low temperature and near-neutral pH. The specific activity, K m and V max of LipU was calculated to 176.7 U/mg, 1.73 μM and 62.24 μM/min respectively. Ionic detergents can inhibit its activity. The active-site residues of LipU were determined to be Ser140, Asp244 and His269 by site-directed mutagenesis. The upregulation of Mycobacterium tuberculosis rv1076 under nutritive stress implicates a role in starvation.

Numerous metro accidents expose the vulnerability of metro system. As cities are rapidly building and expanding metro systems, it is essential to thoroughly explore the nature of metro operation safety. Metro accidents can be regarded as an emergent property that arises from the unusual interactions of system components. These interactions could give rise to the phenomenon that several interrelated hazards simultaneously emerge in one single accident. Understanding these interrelations among hazards is indispensable to study metro operation safety. From this standpoint, 28 hazards and 48 interrelations among hazards were identified from 134 accidents and expert interviews, which were the foundation of establishing metro operation hazard network (MOHN). Whereby complex network theory, seven parameters were applied to further reveal the structural properties of MOHN. The results indicate that the MOHN is a scale-free network for the cumulative degree distribution obeys power-law distribution. The scale-free property of MOHN is indicative of its robustness to random attacks and its vulnerability to deliberate attacks. Nichetargeting controlling hazards of high degrees and betweenness centrality can significantly decrease the metro operation risks. Moreover, MOHN also possesses the small-world property for having a relatively high clustering coefficient and small shortest path length. This indicates that risks would be transmitted very quickly in MOHN. Secondary and derivative hazards should receive enough attention for the rapid propagation of MOHN. Revealing the inherent properties of MOHN assist in making beforehand strategies prior to metro accident and contributes to elevate system safety of metro operation.

The safety climate of construction teams has become increasingly important in the processes of construction safety management because of the significantly high rate of casualties in construction teams. This study examined safety climate dimensions (SCDs) and identified critical safety climate indicators (SCIs) at the level of the construction team from three perspectives: construction team workers, the safety environment, and safety management and supervision. Based on the survey data gathered from the construction team workers in Nanjing, China, a confirmatory factor analysis was carried out. As a result, six SCDs ( workers’ self-perception of safety, workers’ involvement in safety, co-workers’ interaction, safety environment, safety management involvement, and safety personnel support ) were significantly important to the safety climate of the construction teams. An improved model was then developed. Furthermore, the effects of SCIs on SCDs as well as SCDs and SCIs on the safety climate were evaluated and discussed. The results showed that (a) safety management involvement and safety personnel support significantly influenced the safety climate of construction teams more than the other dimensions; (b) working pressure would be more helpful than workers’ safety awareness and mentality for improving the workers’ self-perception of safety ; and (c) safety procedure and policy was the most important indicator of the safety climate among all twenty SCIs for construction teams in China. These findings might be helpful for improving the measurement and management of the safety climate within construction teams.

Recently environment-friendly hydrogen generation for NaBH4 hydrolysis using improved method has attracted much attention. Here a novel catalyst NiB/NiFe2O4 was developed through an impregnation-chemical reduction method, which was utilized in hydrogen production from NaBH4 hydrolysis. In this study, NiFe2O4 ferrite supports were prepared via a combined EDTA-citric acid complexing method. NiFe2O4 ferrites were characterized in terms of phase structure and surface morphologies using X-ray diffractometer as well as scanning electron microscopes. It can be found that the particle size of NiFe2O4 calcined at 873 K is about 30–40 nm which exhibits an optimized spherical morphologies. The factors such as active metal loading amount, reaction temperature and recycling number on NiB/NiFe2O4 catalyst were investigated in detail. A hydrogen generation rate as high as 299.88 ml min−1 g−1 for NiB/NiFe2O4 catalyst can be achieved using 5wt.% NaBH4 solution at 298 K which is much higher than pure NiB. Moreover, an improved recycling stability can be obtained for supported NiB/NiFe2O4 catalyst. The 83.3% of initial catalytic activity can be retained for NiB/NiFe2O4 catalyst after the fifth run. The experimental results show that the usage of NiFe2O4 support can enhance the catalytic activity and recycling stability of NiB active metals.

Stem/progenitor cells serve an important role in the process of blood vessel repair. However, the mechanism of vascular repair mediated by C-X-C chemokine receptor type 4-positive (CXCR4+) bone marrow-derived mesenchymal stem cells (BMSCs) following myocardial infarction remains unclear. The aim of the present study was to investigate the effects of vascular endothelial growth factor (VEGF) on vessel endothelial differentiation from BMSCs. CXCR4+ BMSCs were isolated from the femoral bone marrow of 2-month-old mice and the cells were treated with VEGF. Expression of endothelial cell markers and the functional properties were assessed by reverse transcription-quantitative polymerase chain reaction, flow cytometry and vascular formation analyses. The results indicated that the CXCR4+ BMSCs from femoral bone marrow cells expressed putative cell surface markers of mesenchymal stem cells. Treatment with VEGF induced platelet/endothelial cell adhesion molecule-1 (PECAM-1) and von Willebrand factor (vWF) expression at the transcriptional and translational levels, compared with untreated controls. Moreover, VEGF treatment induced CXCR4+ BMSCs to form hollow tube-like structures on Matrigel, suggesting that the differentiated endothelial cells had the functional properties of blood vessels. The results demonstrate that the CXCR4+ BMSCs were able to differentiate into vessel endothelial cells following VEGF treatment. For cell transplantation in vascular disease, it may be concluded that CXCR4+ BMSCs are a novel source of endothelial progenitor cells with high potential for application in vascular repair.

Based on a Structural Vector Autoregression (SVAR) model, this paper decomposes oil price changes into four components: oil supply shocks, global demand shocks, domestic demand shocks and precautionary demand shocks. Then, this paper investigates the impacts of these oil price shocks on the stock returns of China’s listed companies in the oil industrial chain using data from 2009 to 2014. The empirical results show that the returns of the listed companies in the whole oil industrial chain benefit from appreciation in the oil price, the impacts of oil supply shocks and precautionary demand shocks are the most significant, and there is a structural change in the impacts of oil price shocks in 2012. Among the four oil price shocks, the impacts of oil supply shocks and precautionary demand shocks are the most significant. Moreover, there is a gradual increase in the aggregate contributions of oil price shocks to the changes in stock returns. A robustness check with different global crude oil prices and a different industry classification standard confirms that the above empirical results are robust. The empirical results of the paper imply that stock investors, oil-related companies and the government need pay close attention to sudden changes that may affect current and future oil availability and pay greater attention to the stocks at the two ends of the oil industrial chain.

The objective of this paper is to propose a novel contact structure for 126 kV vacuum interrupters, and determine its arc characteristics. The contact consists of an inner arcing contact and an outer main contact. A 3/4 coil-type contact with contact diameter of 100 mm was used as the arcing contact. A butt type contact with diameter of 140 mm was used as the main contact. For this contact, nominal rated current flows through both the main contact and arcing contact. When breaking the fault current, the main contact first opens and current transfers to arcing contact. Then the arcing contact opens and vacuum arc burns and distinguishes between the arcing contact. Drawn arc experiments of the novel contact were carried out in an L-C discharging circuit. Experiment current was up to 30 kA rms. From the experimental results, the proposed contact can control vacuum arc effectively, and the erosion on outer main contact was slight. With the increasing of vertical distance between inner arcing contact and outer main contact, the arc expanded to outer main contact later. And in partial erosion case, the erosion on outer main contact was more severe than in normal case.