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Carbapenem-resistant Acinetobacter baumannii (CRAB) is a prevalent pathogen contributing to hospital infections. Pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and core-genome MLST (cgMLST) are frequently used methods to illuminate the nosocomial transmission of CRAB. In this study, we compared the discriminatory power of the three typing methods.Antimicrobial susceptibility tests were performed by the broth microdilution and Vitek2 methods. PFGE, MLST and cgMLST were conducted to determine the clonality and phylogenetic relationship of the strains. Whole-genome sequence data were acquired by an Illumina HiSeq 2000, and cgMLST was analysed by the Ridom SeqSphere+ v.7.2.3 software.A total of 149 carbapenem-resistant A. baumannii isolates had 15 different PFGE profiles (A-O type), and 73 of the isolates had related subtypes (A1 and A2), accounting for the majority of type A isolates. The maximum-likelihood phylogenetic analysis based on the cgMLST genes grouped the same PFGE clonal pattern A into nine different clusters. ST_Pasteur grouped all the strains into ST2, whereas ST_Oxford grouped the PFGE clonal pattern A isolates into six STs. In addition, the gdhB allele in the ST_Oxford scheme had two copies in five strains, which complicated the ST_Oxford typing.cgMLST was more discriminant than PFGE and MLST. CgMLST is the most suitable and comprehensive method for genotyping A. baumannii in surveillance and epidemiological research.

Exclusive bus lanes (XBLs) have been widely discussed and implemented worldwide in recent years. An improved and more flexible transit lane management strategy—intermittent bus lanes (IBLs)—prove to be potentially more efficient and car-friendly than XBLs. The common benefit of XBLs and IBLs arises from the fact that they separate the bus and car traffic and hence eliminate the impacts of slowly moving buses on the car traffic. Compared to XBLs, the application of IBLs has not been broadly adopted in the real world so far except very few cases, because managing an urban IBL segment or area typically involves extra traffic signals and message signs and the switch between its regular and protected statuses could potentially cause unexpected traffic chaos and safety issues. The recent emergence of connected and automated vehicle (CAV) technologies, however, favors relieving these concerns and bring the dawn to a future application of this theoretically sound traffic control strategy. This paper is dedicated to evaluating the network performance of XBLs and IBLs and optimizing the networkwide configurations of these two strategies for future urban traffic networks where CAVs prevail. For this purpose, we formulate a system-optimal dynamic traffic assignment (SO-DTA) problem with car-exclusive lane segments, on the basis of a cell transmission model for separate car and bus traffic (CTM-SCB). By limiting its applicable context to morning commute networks and emergency evacuation networks, this model is set with only one real or virtual destination, which greatly eases its modeling and solution complexity. On the basis of the single-destination SO-DTA model, an XBL-based network design problem and an IBL-based network design problem are then both formulated into mixed integer programming models and solved by a discrete optimization solver, where the former problem statically configures bus lanes while the later one allows a dynamic allocation of bus lanes. Insightful findings obtained by applying the models and solver to a synthetic corridor network and a real commute network illustrate the great promise of these two lane-based strategies in mixed car and bus traffic management.

Background Arteriovenous fistulae (AVF) are the preferred mode of vascular access for hemodialysis. Before use, AVF remodel by thickening and dilating to achieve a functional conduit via an adaptive process characterized by expression of molecular markers characteristic of both venous and arterial identity. Although signaling via EphB4, a determinant of venous identity, mediates AVF maturation, the role of its counterpart EphrinB2, a determinant of arterial identity, remains unclear. We hypothesize that EphrinB2 signaling is active during AVF maturation and may be a mechanism of venous remodeling. Methods Aortocaval fistulae were created or sham laparotomy was performed in C57Bl/6 mice, and specimens were examined on Days 7 or 21. EphrinB2 reverse signaling was activated with EphB4-Fc applied periadventitially in vivo and in endothelial cell culture medium in vitro. Downstream signaling was assessed using immunoblotting and immunofluorescence. Results Venous remodeling during AVF maturation was characterized by increased expression of EphrinB2 as well as Akt1, extracellular signal-regulated kinases 1/2 (ERK1/2), and p38. Activation of EphrinB2 with EphB4-Fc increased phosphorylation of EphrinB2, endothelial nitric oxide synthase, Akt1, ERK1/2, and p38 and was associated with increased diameter and wall thickness in the AVF. Both mouse and human endothelial cells treated with EphB4-Fc increased phosphorylation of EphrinB2, endothelial nitric oxide synthase, Akt1, ERK1/2, and p38 and increased endothelial cell tube formation and migration. Conclusions Activation of EphrinB2 signaling by EphB4-Fc was associated with adaptive venous remodeling in vivo while activating endothelial cell function in vitro. Regulation of EphrinB2 signaling may be a new strategy to improve AVF maturation and patency.

In order to investigate the behavior of potassium (K) isotopes during metamorphic dehydration and to further constrain its implications for K recycling in the subduction zone, we measured K isotopic compositions of whole-rocks and separated minerals (phengite, omphacite, amphibole) from Sumdo eclogites, Tibet, using a recently established high-precision analysis method. Our data reveal that the δ41K (‰) of the whole-rock eclogites (−1.64 to −0.24) displays dramatically lower values than observed in fresh mid-ocean ridge basalts (MORB) (−0.43 ± 0.17) and altered MORB (−0.76 to −0.11). In addition, the δ41K values of eclogites show a positive correlation with both K2O contents and K/Nb ratios, which suggests that the low δ41K values were most likely caused by dehydration during subduction. Thus, isotopically heavy K may be released into the mantle wedge, while the light component is subducted into the deep mantle. Therefore, the K isotope systems have the potential to trace subducted crustal materials and to create heterogeneity within the mantle. Mineral separates from Sumdo eclogites are highly heterogeneous in K isotopic compositions, ranging from −0.98 to +0.23 in phengite, from −1.25 to −1.10 in omphacite and from −1.16 to −0.09 in amphibole. The K isotope fractionations between amphibole and phengite and between amphibole and omphacite vary from −0.30 to +0.25 and from −0.04 to +0.63, respectively, indicating K isotopic disequilibrium between amphibole and omphacite/phengite, which might result from the multistage growth of minerals during subduction metamorphism. However, generally phengites show heavier K isotopic compositions than the coexisting omphacite (Δ41Kphengite-amphibole = +0.25) and amphibole (Δ41Kphengite-amphibole = +0.03 ∼ +0.30, except TB193 is −0.25), which may imply that the K isotopic fractionation is controlled by the difference in coordination numbers of K between phengite (6) and omphacite (7 to 8)/amphibole (8).

In this work, Ag3PO4/PANI/Cr:SrTiO3 photocatalysts were designed to effectively eliminate organic pollutants including Rhodamine B and phenol from high salinity wastewater under visible light. The phase composition, optical properties, and morphology of powders were studied, and the effects of inorganic salts on removal performance of the as-prepared particles were also tested. Results showed that the photocatalytic activities of Ag3PO4/PANI/Cr:SrTiO3 composites for Rhodamine B and phenol reached 100% within 10 min and 18 min, respectively. The reaction rate of pure Ag3PO4 was 7 times less than that of the ternary composite with the adding of PANI and Cr:SrTiO3. The activity of Ag3PO4/PANI/Cr:SrTiO3 remained at 92.25% after five cycles, so the photocatalytic and recyclable performance of ternary composite was greatly improved. In addition, when there was SO42− with a content of ranging from 1% to 21%, the degradation activity of the ternary catalyst under visible light was not changed for Rhodamine B, which indicated that the ternary catalyst exhibited the excellent sulfate resistance ability. Results from ESR and radical trapping experiments showed that O2− and h+ made an important contribution to visible-light photocatalytic activities.

Bi2S3/1T@2H-MoS2 composite photocatalyst was designed by a simple and safe microwave hydrothermal synthesis method. 1T@2H-MoS2 enhance the catalytic performance of Bi2S3 by double-sided coordination as an electron hole inhibitor and a cocatalyst. The composite photocatalyst possesses a broad photo-absorption band and exhibits a significant enhancement in the 400–800 nm region. Compared with bare Bi2S3, the Bi2S3/1T@2H-MoS2 composite exhibits significantly enhanced photocatalytic activity for Cr(VI) and methylene blue (MB) degradation under visible light irradiation. This study shows that the introduction of 1T and 2H MoS2 in a semiconductor photocatalyst is a good strategy for optimizing photocatalytic performance.

Hybrid vigour, or heterosis, refers to the increased productivity and growth rate of hybrid offsprings relative to the parents. Various heterosis have been well exploited in fish for fisheries. However, the molecular mechanisms underlying heterosis are largely unknown in fish. In this study, two inbred and hybrid lines between the northern snakehead (NS, Channa argus) and blotched snakehead (BS, Channa maculata) were generated. The analysis on various growth traits, including body length, head length, and body height, showed that hybrid fry obviously exhibited a spontaneous growth heterosis over the inbred. Moreover, the methylation-sensitive amplification polymorphism (MSAP) analysis revealed that the DNA methylation levels were negatively related to the body growth in all fry. Especially, the DNA methylation levels in the hybrid fry were significantly lower than those in the inbred. Additionally, qRT-PCR showed that the snakehead fish Dnmt3a mRNA was initially detectable in embryos at 12 hpf and gradually increased as developing. Intriguingly, the level of Dnmt3a mRNA expression was found to be closely correlated to the DNA methylation level in embryos/fry. The results of this study firstly demonstrated the correlations between growth heterosis, DNA methylation level and Dnmt3a mRNA expression in fish fry. The findings of this study implied that the hybrids' heterosis formation is probably accompanied by DNA methylation alterations and modulated by Dnmt3a gene in fish. This study would provide new clues for further investigations on mechanisms behind heterosis formation in fish hybrid.

The Sumdo metamorphic belt, located in the Lhasa terrane of Tibet, is a key area for unraveling the Paleo-Tethys evolution. In order to identify the fluid evolution in oceanic subduction zones, eclogite from the Sumdo metamorphic belt, has been investigated in a combined study of petrography, mineral chemistry, fluid inclusions and oxygen isotopes. On the basis of petrography and mineral chemistry, two kinds of garnet were distinguished. The core part of Grt-I shows increasing grossular content and contains prograde mineral inclusions, suggesting that it grew during prograde metamorphism, while the rim of Grt-I shows varying grossular and pyrope contents, representing subsequent overgrowth. Grt-II displays a composition comparable with the outermost part of Grt-I, indicating that Grt-II grew at the peak or initial retrograde stage. Garnet trace element zoning patterns and P-T estimates suggest that the Sumdo eclogite experienced a heating stage during an initial exhumation after the peak metamorphic event. Based on textural criteria and host minerals, three types of fluid inclusions were distinguished: Type-I are primary NaCl dominated intermediate to high-salinity (10–22 wt% NaCl) fluid inclusions hosted by omphacite, which were most likely released during dehydration of the subducting oceanic crust and reflect the composition of eclogite-facies fluids; Type-II are defined as primary low-salinity (1–6 wt% NaCl) fluid inclusions hosted by epidote/clinozoisite, representing fluids that evolved towards low-salinity during uplift; Type-III are secondary low-salinity (0–7 wt% NaCl) fluid inclusions hosted by matrix quartz (i.e., minerals other than the mineral inclusions) and rarely by omphacite and must have formed at a very late stage. In addition, the eclogite displays δ18O values (δ18O = +5.0 to +8.9‰) similar to its protolith, low-temperature altered oceanic crust (δ18O = +4.9 to +12.7‰). The equilibrium oxygen isotope fractionations (Δ18OQtz-Min) between quartz and garnet/omphacite suggest isotopic equilibrium and a closed fluid system during eclogite facies metamorphism. Our data indicate that the Sumdo eclogite experienced “hot” exhumation, during which large amounts of fluids were released by dehydration. Fluids in the Sumdo eclogite were typically aqueous fluids of varying salinities and now preserved as fluid inclusions in HP metamorphic minerals. In comparison with continental subduction zones, we confirm previous conclusion that the fluid regime in oceanic subduction zones is relatively simple (i.e. mainly NaCl bearing brines) with seawater-altered slabs as the dominant source.