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Nitrogen is an essential component of living organisms and a major nutrient that limits life on Earth. Until now, freely available nitrogen mainly comes from atmospheric nitrogen, but most organisms rely on bioavailable forms of nitrogen, which depends on the complex network of microorganisms with a wide variety of metabolic functions. Microbial-mediated nitrogen cycling contributes to the biogeochemical cycling of wetlands, but its specific microbial abundance, composition, and distribution need to be studied. Based on the metagenomic data, we described the composition and functional characteristics of microbial nitrogen cycle-related genes in the Napahai plateau wetland. Six nitrogen cycling pathways existed, such as dissimilatory nitrate reduction, denitrification, nitrogen fixation, nitrification, anammox, and nitrate assimilation. Most genes related to the nitrogen cycling in this region come from bacteria, mainly from Proteobacteria and Acidobacteria. Habitat types and nitrogen cycle-related genes largely explained the relative abundance of total nitrogen pathways. Phylogenetic trees were constructed based on nitrogen cycle-related genes from different habitats and sources, combined with PCoA analysis, most of them clustered separately, indicating richness and uniqueness. Some microbial groups seemed to be special or general in the nitrogen cycling. In conclusion, it suggested that microorganisms regulated the N cycling process, and may lead to N loss throughout the wetland, thus providing a basis for further elucidation of the microbial regulation of N cycling processes and the Earth’s elemental cycles. [ABSTRACT FROM AUTHOR]

Microbial communities of wetlands play key roles in the earth's ecology and stability. To elucidate the cold adaptation mechanisms of bacteria in plateau wetlands, we conducted comparative genomic analyses of Pseudomonas sivasensis and closely related lineages. The genome of P. sivasensis W-6, a cold-adapted bacterium isolated from the Napahai plateau wetland, was sequenced and analyzed. The genome length was 6,109,123 bp with a G+C content of 59.5%. Gene prediction yielded 5360 protein-coding sequences, 70 tRNAs, 24 gene islands, and 2 CRISPR sequences. The isolate contained evidence of horizontal gene transfer events during its evolution. Two prophages were predicted and indicated that W-6 was a lysogen. The cold adaptation of the W-6 strain showed psychrophilic rather than psychrotrophic characteristics. Cold-adapted bacterium W-6 can utilize glycogen and trehalose as resources, associated with carbohydrate-active enzymes, and survive in a low-temperature environment. In addition, the cold-adapted mechanisms of the W-6 included membrane fluidity by changing the unsaturated fatty acid profile, the two-component regulatory systems, anti-sense transcription, the role played by rpsU genes in the translation process, etc. The genome-wide analysis of W-6 provided a deeper understanding of cold-adapted strategies of bacteria in environments. We elucidated the adaptive mechanism of the psychrophilic W-6 strain for survival in a cold environment, which provided a basis for further study on host-phage coevolution. [ABSTRACT FROM AUTHOR]

Viruses play important roles in ecosystems by interfering with the central metabolic pathways of the host during infection via the expression of auxiliary metabolic genes (AMGs), altering the productivity of ecosystems and thus affecting geochemical cycling. In this study, the genetic diversity of phosphorus metabolism AMGs phoH, phoU and pstS was investigated by phylogenetic analysis, PCoA analysis, and alpha diversity analysis based on metagenomic data. It was found that the majority of the sequences were unique to Napahai plateau wetland. It was shown that the genetic diversity of phoH, phoU and pstS genes was independent of both habitats and host origins. In addition, the metabolic pathway of AMGs associated with the phosphorus cycling was identified based on metagenomic data. When phosphorus is deficient, virus utilizes AMGs to affect the metabolic pathway, contributing to higher phosphorus levels in the host and facilitating virus survival, replication, and propagation in the host cell. [ABSTRACT FROM AUTHOR]

To protect Cr–50Nb alloys from high-temperature oxidation, the Al 2 O 3 /Si–Al multilayer coatings were produced by pack cementation process, followed by sol–gel process and hot pressing. The results indicate that the multilayer coating is dense and exhibits good adherence to the substrate, which consists of a compact Al 2 O 3 outer layer and an inner layer composed of Si, Al, Cr, Nb. Uncoated Cr–50Nb alloy occurs catastrophic oxidation at the initial oxidation stage at 1200 °C. However, the scale spalling resistance of the multilayer coating is improved significantly, and the multilayer coating exhibits good resistance to oxidation. During cyclic oxidation in air at 1200 °C for 100 h, the weight loss is 0.13 mg/cm 2 and the mass gain is 3.38 mg/cm 2 . [ABSTRACT FROM AUTHOR]

YSZ@Ni core–shell nanoparticles were used to prepare a composite coating on an Fe-based alloy by laser cladding. Samples were sintered layer-by-layer with a laser power P in the range of 800–2000 W, scanning velocity V in the range of 240–600 mm/min, and the laser beam diameter D =5 mm. The microstructures, phase constituents, and microhardness of a monolayer coating were investigated and compared with those of a multilayer coating. The results showed that the existing forms of core-YSZ in the monolayer coating comprised of four types: flower-like YSZ aggregates, few nanoscale YSZ particles at the grain boundaries, proeutectic YSZ phases, and YSZ/FeCr 2 O 4 eutectic structure. Moreover, the multilayer coating structure was more homogeneous than the monolayer one. Interestingly, the YSZ@Ni core–shell nanoparticles were separated into core-YSZ and shell-Ni layer with a stratification feature during the laser cladding process. [ABSTRACT FROM AUTHOR]

To protect Cr–50Nb alloys from high-temperature oxidation, the silicide diffusion coating and Si–Al coating were produced by pack cementation. The results indicate that the two coatings have three-layer structure and the interfaces are smooth. Uncoated Cr–50Nb alloy occur catastrophic oxidation at the initial oxidation stage at 1200 °C. However, the scale spalling resistance of the two coatings are improved significantly, and Si–Al coating exhibits excellent resistance to oxidation. During cyclic oxidation in air at 1200 °C for 100 h, the weight loss of Si–Al coating is 1.39 mg/cm 2 and the mass gain is 6.01 mg/cm 2 . [ABSTRACT FROM AUTHOR]

How to achieve atomical regulation of quantitative relationship between materials has become a key strategy to develop solid electrolyte with excellent electrochemical properties for fluoride-ion batteries. Based on the unsatisfactory fluoride-ion conductivity of BaSnF 4 (3.50 × 10−4 S/cm) at 300 K, we have further designed successfully the optimal structure of Ba 0.875 Nd 0.125 SnF 4.125 with much higher fluoride-ion conductivity (5.35 × 10−3 S/cm at 300 K) after clarifying the physical and chemical role of Nd-dopant in accelerating fluoride-ion diffusion at atomic scale. This attributes to the case that structural reconstruction of barium-fluoride tetrahedron occurs with Nd atomic concentration of 12.5%, inducing the increasing disorder degree of barium-fluoride coordinate structure. As a result, it owing low fluorine-ion diffusion barrier (0.18 eV). Meanwhile, it can afford high and wide range stable of voltage plateau when Ba (Nd) metal is served as anode materials (4.86 V – 5.66 V for Ba and 6.38 V–7.57 V for Nd). Besides, it is noted Nd 5 Sn 3 is expected to the most favorable raw material to provide Nd-dopant for the fabrication of Ba 0.875 Nd 0.125 SnF 4.125. Meanwhile, it is also confirmed that Ba 0.875 Nd 0.125 SnF 4.125 has excellent thermal stability at 300 K by simulation. This study cases new insights to design quickly and accurately solid electrolyte for fluoride-ion batteries. [Display omitted] • Ba 0.875 Nd 0.125 SnF 4.125 has high fluoride-ion conductivity (5.35 × 10−3 S/cm at 300 K). • Ba 0.875 Nd 0.125 SnF 4.125 has excellent thermal stability. • Ba 0.875 Nd 0.125 SnF 4.125 has excellent electrochemical stability. [ABSTRACT FROM AUTHOR]

Abstract: The Lorentz and Lorentz–Gauss beams are extended to the nonparaxial regime. Analytical propagation expressions of nonparaxial Lorentz and Lorentz–Gauss beams in free space are derived, and the propagation of paraxial Lorentz and Lorentz–Gauss beams is treated as a special case of our general results. The propagation properties of Lorentz and Lorentz–Gauss beams are illustrated and compared with numerical examples. [ABSTRACT FROM AUTHOR]

Abstract: A method for the simulation and optimization of the source-field distribution of a diode bar laser (DBL) beam by using the stimulated annealing and experimental data in the far field is proposed and illustrated by an example of a DBL JOLD-60-CPNN-1L, showing the applicability of the method. As compared with the previous models, this method is not restricted to the type of diode lasers (DLs), and the reconstructed results are accurate so long as the experimental data are sufficiently accurate. [Copyright &y& Elsevier]

Abstract The uniform distribution of nano-sized conductive fillers in conductive papers is still a big challenge. Herein, we report a novel cycled film-liquid interface culture (CFLIC) method to produce flexible, ultra-strong, and highly conductive papers based on bacterial cellulose (BC) and graphene (GE). During this biosynthesis process, the GE nanosheets uniformly dispersed in the culture medium are closely bundled by growing BC nanofibers, which leads to a sophisticated multilayered GE/BC nanocomposite. The as-prepared GE/BC paper shows greatly improved tensile strength (93% improvement) and electrical conductivity (10 orders of improvement) over bare BC paper while still retaining the excellent flexibility of BC paper. The strategy is versatile, facile, and scalable and the resultant paper shows promise in numerous fields such as energy storage and electromagnetic interference shielding. Graphical abstract Image 1 Highlights • Flexible conductive papers were made via a film-liquid interface culture method. • The papers consist of bacterial cellulose and highly dispersed graphene nanosheets. • The papers show greatly improved tensile strength and electrical conductivity. [ABSTRACT FROM AUTHOR]

Background: Brucine is an alkaloid derived from the natural plant seeds of Strychnos nux-vomica, also known as a medicinal herb, and broadly employed in Chinese medicine for liver cancer. Objectives: The main intention of these hypothesis anticancer effects of brucine on 7,12-dimethylbenz(a)anthracene (DMBA)-induced skin cancer in mouse model through phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) regulating signaling pathway via the suppressive effect on cell proliferation and apoptotic pathways in mouse model. Materials and Methods: Brucine action on DMBA-induced mouse skin body weight, tumor volume, histology, biochemical, molecular marker analysis using spectrophotometric, Western blotting, and real-time polymerase chain reaction analysis. Results: Brucine stifled the lipid peroxidation (TBARS), suggestively augmented the levels of antioxidants (superoxide dismutase, catalase, glutathione peroxidase, and glutathione), and brought back the status of xenobiotic enzymes (Cyt-p450, Cyt-b5, and glutathione S-transferases). In brucine administered since skin tissues presented the cell proliferative protein marker expression of PI3K, and AKT were downregulated compared to the DMBA-applied skin tumor tissues protein. Further, brucine has downregulated the proliferating cell nuclear antigen, cyclin-D1, and p53 expressions. In the apoptotic expression, markers such as Bcl-2, Bax, caspase-3, and caspase-9 were upregulated compared to the DMBA-induced skin cancer. From these data, we diseased and brucine potential to suppress the proliferative cell markers induces apoptotic expressions. Conclusion: The current search settled that administering brucine chemopreventive and chemotherapeutic effect means for the cancer management in clinical tactic. [ABSTRACT FROM AUTHOR]

High-performance anode materials are highly desirable to the application of lithium-ion batteries (LIBs) in electric/hybrid electric vehicles and renewable energy storage. Herein, a nanocomposite composed of CoFe 2 O 4 nanocubes homogeneously dispersed and closely stuck on graphene (CoFe 2 O 4 /G) has been constructed via a facile one-pot strategy. The obtained results show that the introduced graphene oxide can trigger the formation of nanocubic CoFe 2 O 4 and the intimate interfacial contact between CoFe 2 O 4 and graphene can be achieved. The CoFe 2 O 4 /G electrode displays outstanding cycling performance (1109 mA h g −1 after 100 cycles at 0.2 A g −1 and 835 mA h g −1 after 200 cycles at 1 A g −1 ) and excellent rate capability (420 mA h g −1 at 5 A g −1 ). It is believed that this synthesis strategy can be extended to preparation of other ferrite/graphene nanocomposites. [ABSTRACT FROM AUTHOR]

In this study, we report the construction of a ternary flexible nanocomposite of bacterial cellulose/graphene/polyaniline (BC/GE/PANI) via a facile two-step strategy. Bacterial cellulose/graphene (BC/GE) is first prepared by a novel in situ membrane-liquid-interface method, in which the three-dimensional continuous BC nanofibers can be maintained and the introduced GE can improve the mechanical properties mainly due to the uniform dispersion of GE in the BC matrix. To construct the effectively interconnected conductive paths between separated GE nanosheets, polyaniline (PANI) is simultaneously deposited on the surfaces of both BC nanofibers and GE nanosheets to obtain BC/GE/PANI with excellent electrical conductivity. It is found that the as-prepared BC/GE/PANI has an electrical conductivity of 1.7 ± 0.1 S cm −1 , which is higher than most of PANI-based composites. It is believed that the BC/GE/PANI nanocomposite possesses great potential for applications in electromagnetic shielding and flexible electrodes. [ABSTRACT FROM AUTHOR]

Thermomechanical behavior has an important effect on reliability and lifetime of high-power diode lasers (HPDLs). Finite-element analysis (FEA) model and analytical solution model of the conduction-cooled package (CS) HPDL are established to analyze the thermomechanical behavior including normal stress, shearing stress, and displacement in reflowing process and working process. Moreover, in order to simulate and analyze the thermomechanical behavior in total process, reflowing thermal stress and displacement are considered as the residual stress and the initial condition of working process. We find that shearing stress is the origin of other thermomechanical behavior due to coefficient thermal expansion (CTE) mismatch, while both CTE mismatch and temperature gradient cause the thermal stress and displacement in working process. Although thermal stresses and displacement induced in reflowing process are larger than working process, the working process has great impact on smile and causes much worse total smile. The influence of different working temperatures on smile is also studied in total process with analytical solution, FEA, and experiment. For analytical solution, the total smile value is inversely proportional to the working temperature, while for FEA the smile value is proportional to the working temperature and FEA result accords with experimental result. [ABSTRACT FROM PUBLISHER]

Purpose: Cancer is still a clinical challenge, with many efforts invested in order to achieve timely detection. Unexplained elevated blood carcinoembryonic antigen levels are occasionally observed in an asymptomatic population and considered as a risk factor of cancers. The purpose of this study was to determine the validity of 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography (F-18 FDG-PET/CT) for detecting cancer in an asymptomatic population with an unexplained elevation in blood carcinoembryonic antigen (CEA) levels. Methods: This retrospective study included a total of 1920 asymptomatic examinees conducted from August 2011 through September 2013. The participants underwent CEA assay and conventional medical imaging (CEA-conventional), or CEA assay and F-18 FDG-PET/CT (CEA-PET/CT). The validity of conventional medical imaging and CEA-PET/CT scanning for detecting cancer and early-stage cancer in an asymptomatic population with an unexplained elevation in blood CEA levels were evaluated. Results: Sensitivity, specificity, cancer detection rate, missed cancer detection rate, early-stage cancer detection rate, and early-stage cancer ratio using the CEA-PET/CT scanning were 96.6 %, 100 %, 10.4 %, 0.4 %, 3.7 %, and 34.5 %, respectively. In contrast, the corresponding values obtained using the conventional medical imaging were 50.6 % ( P < 0.0001), 100 % ( P > 0.9999), 50.6 % ( P < 0.0001), 99.9 % ( P = 0.055), 2.6 % ( P < 0.0001), 2.5 % ( P = 0.04), 0.7 % ( P = 0.0004), and 14.5 % ( P = 0.002), respectively. Conclusion: The F-18 FDG-PET/CT scanning significantly improved the validity of the cancer detection program in the asymptomatic population with an unexplained elevation in CEA levels. [ABSTRACT FROM AUTHOR]

The package structure critically influences the major characteristics of semiconductor lasers, such as thermal behavior, output power, wavelength, and far-field distribution. In this paper, a new single emitter package structure called F-mount is designed and compared with the conventional package structure C-mount. The influence of package structure on their performances is characterized and analyzed. The thermal resistances of lasers with different package structures are calculated through simulation, and are contrasted with experimental results. Some devices are also tested for the maximum output power level. Under the continuous wave (CW) condition, the maximum power of F-mount reaches 12.6 W at 808 nm while the output power only reaches 10.9 W for C-mount. Under the condition of 0.5% duty cycle (100 \mus, 50 Hz), the catastrophic optical mirror damage level reaches 58.7 W at 74 A for F-mount, and 54.8 W at 57 A for C-mount are reported for the first time. It is experimentally found that there is an obvious wavelength difference between the two type structure lasers: about 1.37 nm in CW mode and 2.89 nm in quasi CW mode. Theoretical analysis shows that red-shift and blue-shift is a result of external strain in the package process of F-mount and C-mount, respectively. It is also found that the package structure has an effect on the divergence angle of slow axis far fields, but little impact on that of fast axis far fields. The analysis shows that package structure has a strong influence on the performance of the laser; therefore, the package should be optimized to achieve better performance for some special applications. [ABSTRACT FROM AUTHOR]

Summary Macrophages are a dominant leukocyte population in the tumor microenvironment and actively promote cancer progression. However, the molecular mechanism underlying the role of macrophages remains poorly understood. Here we show that polarized M2 macrophages enhance 3-phosphoinositide-dependent protein kinase 1 (PDPK1)-mediated phosphoglycerate kinase 1 (PGK1) threonine (T) 243 phosphorylation in tumor cells by secreting interleukin-6 (IL-6). This phosphorylation facilitates a PGK1-catalyzed reaction toward glycolysis by altering substrate affinity. Inhibition of PGK1 T243 phosphorylation or PDPK1 in tumor cells or neutralization of macrophage-derived IL-6 abrogates macrophage-promoted glycolysis, proliferation, and tumorigenesis. In addition, PGK1 T243 phosphorylation correlates with PDPK1 activation, IL-6 expression, and macrophage infiltration in human glioblastoma multiforme (GBM). Moreover, PGK1 T243 phosphorylation also correlates with malignance and prognosis of human GBM. Our findings demonstrate a novel mechanism of macrophage-promoted tumor growth by regulating tumor cell metabolism, implicating the therapeutic potential to disrupt the connection between macrophages and tumor cells by inhibiting PGK1 phosphorylation. Graphical Abstract Highlights • Macrophages regulate tumor cell aerobic glycolysis through PGK1 • PGK1 T243 phosphorylation regulates the direction of PGK1-catalyzed reaction • Inhibition of PGK1 T243 phosphorylation abrogates protumoral function of macrophages • PGK1 T243 phosphorylation correlates with grades and prognosis of GBM patients Macrophages are a dominant leukocyte population in the tumor microenvironment and actively promote cancer progression. Zhang et al. demonstrate that resident tissue macrophages secrete IL-6 to regulate the direction of a PGK1-catalyzed reaction by increasing PDPK1-dependent PGK1 phosphorylation in tumor cells, promoting tumor cell glycolysis and tumorigenesis. [ABSTRACT FROM AUTHOR]