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We use the multiband Fe-based superconductor (FeSC) Ba0.5K0.5Fe2As2 and the conventional superconductor Nb to fabricate a hybrid Josephson junction where an Al layer serves as a highly transparent barrier. Detailed electrical transportations are studied including the Shapiro steps and the Fraunhofer-like pattern, which indicate strong Josephson effects. An unusual temperature-dependent critical current was observed, which cannot be well described by the conventional Ambegaokar–Baratoff relation. We utilize a model considering both multiband properties in the FeSC and the conventional superconductor/normal metal/superconductor Josephson junction theory, proving that this temperature dependence on critical current is attributed to the barrier transparency of the Josephson junction. We hope our studies can be a reference for the applications or physics research of FeSC Josephson junctions. [ABSTRACT FROM AUTHOR]

The aim of present work is to evaluate pyrolysis characteristics of poly(methyl methacrylate) (PMMA) and its blends with sugarcane bagasse (SB) contents of 10 and 20 mass % for the purpose of exploring the effect of SB on pyrolysis of PMMA. Non-isothermal pyrolysis determinations of three PMMA samples were performed thermogravimetrically and the initial pyrolysis temperatures of two PMMA blends are significantly lower than that of pure PMMA while the main pyrolysis shifts to higher temperature range. Using model-free isoconversional methods, pyrolysis activation energies calculated are varying within 71.7 ~ 154.0, 107.8 ~ 192.0 and 121.3 ~ 171.0 kJ·mol−1 for PMMA and its 10 or 20 mass % SB blends, respectively. The added SB turns to increase the activation energy of PMMA and thus make pyrolysis of PMMA become more arduous to accomplish. With the model-fitting method, the order-based F2/3, F3 and F3 chemical reaction models are found to be the most appropriate pyrolysis mechanisms for PMMA and its 10 or 20 mass % SB blends, respectively. Accordingly, their pre-exponential factor values are estimated to separately span in the range of 3.23 × 104 ~ 1.76 × 1011, 3.52 × 108 ~ 7.63 × 1016 and 1.55 × 1010 ~ 1.13 × 1015 min−1. The findings acquired from present work can provide necessary information for performing potential pyrolysis designs of PMMA and its biomass blended wastes. [ABSTRACT FROM AUTHOR]

In this research project, we first synthesized the magnetic manganese nanocatalyst by immobilizing the MnCl2 on the surface of magnetic Fe3O4 nanoparticles modified with catechol and piperazine/phenanthroline ligand [Fe3O4@Catechol/PZ-Phen-MnCl2], then we evaluated its catalytic performance in the synthesis of propargyl amines through the A3 and KA2-coupling three-component reactions aromatic aldehydes or ketones, with alkynes, and amines. FT-IR, SEM, TEM, EDX, XRD, TGA, VSM, ICP-OES and elemental mapping analyzes confirmed the successful synthesis of Fe3O4@Catechol/PZ-Phen-MnCl2 nanocatalyst. The results of the coupling reactions confirmed that the Fe3O4@Catechol/PZ-Phen-MnCl2 nanocomposite is a very efficient catalyst for the preparation of various derivatives of propargyl amines. This method has significant features compared to the previous methods, which can be mentioned as follows: synthesis of products with very high efficiency, carrying out the reaction under mild conditions and compatible with the environment, using green and recyclable catalyst, can being applicable to a wide range of substrates and providing NMR analysis for all propargyl amine products.Graphical Abstract: In this research project, we first synthesized the magnetic manganese nanocatalyst by immobilizing the MnCl2 on the surface of magnetic Fe3O4 nanoparticles modified with catechol and piperazine/phenanthroline ligand [Fe3O4@Catechol/PZ-Phen-MnCl2], then we evaluated its catalytic performance in the synthesis of propargyl amines through the A3 and KA2-coupling three-component reactions aromatic aldehydes or ketones, with alkynes, and amines. FT-IR, SEM, TEM, EDX, XRD, TGA, VSM, ICP-OES and elemental mapping analyzes confirmed the successful synthesis of Fe3O4@Catechol/PZ-Phen-MnCl2 nanocatalyst. The results of the coupling reactions confirmed that the Fe3O4@Catechol/PZ-Phen-MnCl2 nanocomposite is a very efficient catalyst for the preparation of various derivatives of propargyl amines. This method has significant features compared to the previous methods, which can be mentioned as follows: synthesis of products with very high efficiency, carrying out the reaction under mild conditions and compatible with the environment, using green and recyclable catalyst, can being applicable to a wide range of substrates and providing NMR analysis for all propargyl amine products. [ABSTRACT FROM AUTHOR]

Tm3+ doped YAlO3 (Tm:YAP) crystals with different concentrations were grown successfully by Czochralski method. The full width at half maximum of 0.007–0.008° shows high crystalline quality. The shape of dislocation etching pit is consistent with its crystal structure. The absorption spectra show an intensive peak located at 794 nm. The fluorescence lifetimes of 6.06, 4.68, 4.22, 4.01, and 1.93 ms decrease monotonically with the increase of Tm3+ concentration in the range of 2–7.5 at%. The fluorescence spectra exhibit two strong peaks appeared near 1775 and 1853 nm, respectively. Among them, the 4 at.% Tm:YAP crystal possesses the largest fluorescence intensity at 1853 nm, indicating that it is a promising gain material operated at ~ 1.9 μm for the development of diode-pumped solid-state lasers and the dopant concentration larger than 4 at.% may cause decline in laser performance owing to larger reabsorption loss and higher nonradiative decay rate. [ABSTRACT FROM AUTHOR]

The application of lipophilic composite nanoparticle photocatalysts to denitrification is an important issue, because the lipophilic catalyst exhibits excellent performance compared to other photocatalysis. Taking inspiration from the super-hydrophobic self-cleaning ability of lotus leaf, we reported here that BiVO4–TiO2-570/sepiolite nanosheet composites were prepared by a facile hydrothermal method. The photo-generated carriers in the heterojunction can be separated efficiently and rapidly under the electric field formed in the space charge region to enhance the catalytic activity and lifetime. In this paper, we organically modified the catalyst by adding silane coupling agent (KH-570), which not only reduces the specific surface energy of the catalyst, but also realizes the lipophilicity by constructing the micro-nano structure, so that it is uniformly dispersed in the oil. Meanwhile, using inexpensive nano-sepiolite as a carrier to provide an electron transport medium, accelerate hole-electron separation and increase specific surface area. The catalytic performance of the lipophilic composite nanoparticles was demonstrated by the photocatalytic degradation rate of pyridine contained in simulation oil. The experiment results shows that modified super-lipophilic nanoparticles was obviously higher than that of pure TiO2, which might provide a simple and environmentally friendly approach for the photocatalytic degradation of oil nitrides. [ABSTRACT FROM AUTHOR]

An Er:Y3Ga5O12 crystal doped with 30 at% Er3+ was grown by the Czochralski method. The crystal structure and component, thermal and spectroscopic properties are studied systematically. The laser performance of a Φ 3 mm × 66 mm Er:YGG crystal was investigated with LD side-pumped method in the CW mode. The maximum output power of 7.25 W is much higher than that has been realized in the LD end-pumped Er:YGG crystal. The results indicate that the Er:YGG crystal is an ideal material to realize 3 μm laser and the LD side-pumping is a preferred approach to achieve high-power CW laser. [ABSTRACT FROM AUTHOR]

The rapid development of mobile broadband services with continuously increasing traffic volumes has resulted in a number of challenges, including ubiquitous network coverage, high bandwidth, and reliable services for reasonable price, etc. To address these challenges, evolved packet system (EPS) is proposed as the evolution of the packet core network. While resource management and load balancing issues in EPS are discussed in 3GPP standardization, relatively few research works consider mechanism design for load information monitoring and evaluation. Furthermore, even though some load balancing algorithms have been proposed for integrated networks, the load balancing scheme design which achieves the optimization of joint system performance has not been extensively studied. In this paper, an inter-access system anchor based load balancing mechanism is introduced which performs load monitoring and evaluation for access gateways and networks, and an optimal load balancing algorithm is proposed for heterogeneous integrated networks. To characterize the performance of integrated networks, the concept of utility function is introduced and the comprehensive performance of integrated networks which support both single type service and multimedia service is modeled mathematically. Applying vertical handoff as an efficient mechanism for achieving load balancing, the optimal number of handoff users is obtained through solving the optimization problem. Numerical results demonstrate that load balancing between access networks can be achieved, and the optimal number of handoff users corresponding to the maximal joint network utility can be obtained. [ABSTRACT FROM AUTHOR]

Poly (β- l-malic acid) (PMLA) is a water-soluble polyester with many attractive properties in chemical industry and medicine development. However, the low titer of PMLA in the available producer strains limits further industrialization efforts and restricts its many potential applications. In order to solve this problem, a new strain with the distinguished high productivity of PMLA was isolated from fresh plants samples. It was characterized as the candidate of Aureobasidium pullulans based on the morphology and phylogenetic analyses of the internal transcribed spacer sequences. After the optimization of culture conditions, the highest PMLA concentration (62.27 g l) could be achieved in the shake flask scale. In addition, the contribution of the carbon flux to exopolysaccharide (EPS) and PMLA could be regulated by the addition of CaCO in the medium. This high-level fermentation process was further scaled up in the 10 l benchtop fermentor with a high PMLA concentration (57.2 g l) and productivity (0.35 g l h), which are the highest level in all the literature. Finally, the suitable acid hydrolysis conditions of PMLA were also investigated with regard to the production of l-malic acid, and the kinetics of PMLA acid hydrolysis was modeled to simulate the whole degradation process. The present work paved the road to produce this multifunctional biomaterial (PMLA) at industrial scale and promised one alternative method to produce l-malic acid in the future. [ABSTRACT FROM AUTHOR]

Poly(β-L-malic acid) (PMLA) is a water-soluble, biodegradable, and biocompatible polymer with broad prospective applications and can be hydrolyzed to produce widely used acidulant L-malic acid. In order to meet an increasing demand of PMLA, we employed two effective cell-recycling strategies to produce PMLA from raw cassava hydrolysate by Aureobasidium pullulans ZD-3d. In fed-batch fermentation with raw cassava hydrolysate, 101.9 g/L PMLA was obtained with the productivity and yield of 0.77 g/L/h and 0.40 g/g, respectively. Further, three times of membrane filtration–based cell recycling fermentation was carried out, with a high productivity and yield of 1.04–1.64 g/L/h and 0.5–0.84 g/g achieved, respectively. While harnessing centrifugation-based cell recycling fermentation for five times, the productivity and yield approached 0.98–1.76 g/L/h and 0.78–0.86 g/g, respectively. To our knowledge, the processes showed the highest average PMLA productivity compared with others using low-cost biomass, which offered efficient and economical alternatives for PMLA production. Key points: • PMLA production from raw cassava hydrolysate by Aureobasidium pullulans was studied • High PMLA productivity and yield were obtained via two cell recycling strategies • The highest average PMLA productivity from low-cost biomass to date was achieved [ABSTRACT FROM AUTHOR]

Yb3+ and Ho3+ co-doped Lu2.55Y0.45Al5O12 (Yb,Ho:LuYAG) crystal with a size of Φ 28 mm × 120 mm was successfully grown by the Czochralski method. The lattice parameters of the as-grown Yb,Ho:LuYAG crystal were obtained by Rietveld refinement with the XRD data. The result of X-ray rocking curve indicated that the grown crystal has a high crystalline quality. From strong absorption band near 935 nm and emission bands within 2700–3000 nm, we found that the Yb3+ ions can be acted as the sensitizer for the activator ions Ho3+. Furthermore, the lifetimes of the 5I6 and 5I7 levels of the Ho3+ ions were 68.25 μs and 7.58 ms, respectively. These results indicated that the Yb,Ho:LuYAG crystal is a promising gain material for 2.91 μm laser pumped by a 940 nm LD. [ABSTRACT FROM AUTHOR]

A novel series of ocotillol-type triterpenoid derivatives have been synthesized to evaluate for their antibacterial activity, structure-activity relationships (SARs), and antibacterial mechanism. Compound (Vl), which were found to be the most active one, displayed good antibacterial activity with minimum inhibitory concentrations (MICs) of 2–8 μg/mL against Gram+ bacteria and 8–32 μg/mL against Gram– bacteria. Further testing against drug-resistant bacteria also showed that (Vk) and (Vl) exhibited potent antibacterial activity with MICs of 4–32 μg/mL against MRSA and K. pneumonia. The following synergistic antibacterial activity revealed that compound (Vl) significantly improved the susceptibility of MRSA USA300 and E.coli DH5α to kanamycin and chloramphenicol. Further research suggested that (Vl) displayed obvious bactericidal activity against MRSA at 2 MIC while it only showed bacteriostatic effects at MIC. This active molecule (Vl) also induced bacterial resistance more slowly than norfloxacin and chloramphenicol. Moreover, compound (Vl) not only had low toxicity, but also could rapidly inhibit the growth of drug-resistant bacteria by damaging cell membranes, and the incidence of drug resistance was obviously lower than that of positive control group. Additionally, the properties of absorption, distribution, metabolism, and excretion (ADME) of these compounds demonstrated their drug-likeness with moderate oral absorption and blood-brain barrier permeability. Preliminary in vivo results also confirmed that (Vl) could reduce the number of viable colonies in the infected cornea at a high concentration (3.2 mg/mL). These results suggested that ocotillol-type triterpenoid derivatives represent as potential leads for the development of antibacterial agents against antibiotic-resistant superbugs and deserve further attention. [ABSTRACT FROM AUTHOR]

Uncovering mechanisms underlying epileptogenesis aids in preventing further epilepsy progression and to lessen seizure severity and frequency. The purpose of this study is to explore the antiepileptogenic and neuroprotective mechanisms of EGR1 in neuron injuries encountered in epilepsy. Bioinformatics analysis was conducted to identify the key genes related to epilepsy. The mice were rendered epileptic using the kainic acid protocol, followed by measurement of seizure severity, high amplitude and frequency, pathological changes of hippocampal tissues and neuron apoptosis. Furthermore, an in vitro epilepsy model was constructed in the neurons isolated from newborn mice, which was then subjected to loss- and gain-of-function investigations, followed by neuron injury and apoptosis assessment. Interactions among EGR1, METTL3, and VIM were analyzed by a series of mechanistic experiments. In the mouse and cell models of epilepsy, VIM was robustly induced. However, its knockdown reduced hippocampal neuron injury and apoptosis. Meanwhile, VIM knockdown decreased inflammatory response and neuron apoptosis in vivo. Mechanistic investigations indicated that EGR1 transcriptionally activated METTL3, which in turn downregulated VIM expression through m6A modification. EGR1 activated METTL3 and reduced VIM expression, thereby impairing hippocampal neuron injury and apoptosis, preventing epilepsy progression. Taken together, this study demonstrates that EGR1 alleviates neuron injuries in epilepsy by inducing METTL3-mediated inhibition of VIM, which provides clues for the development of novel antiepileptic treatments. [ABSTRACT FROM AUTHOR]

40 small watersheds in the Source Area of the Yellow River were investigated recently to sample surface waters, groundwater and ground ice, and their water isotopic signatures (2H, 18O, 3H, and 222Rn) have been measured. A novel isotope mass balance approach was developed to estimate annual surface and surface flow discharges in catchment combined water age dating. This approach revealed the changing surface and subsurface runoff patterns were along the hydrological trajectory of progressive permafrost degradation. To build up the linkages between the hydrological indictors and environmental and biological features was recommended, which would benefit a better understanding the significant impacts of permafrost degradation on social, ecological and economic developments in cold regions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to obtain large deviations, moderate deviations and normal deviations for the convergence of martingale generated by a supercritical Galton–Watson process with a Poisson process as its time index. Harmonic moments and Shröder index play an important role in the proofs. [ABSTRACT FROM AUTHOR]

Recently, wearable electronic devices and human–computer interaction are developing prosperously, which expands the requirement of flexible sensing materials. Graphene and its derivatives with extraordinary advantages are highly attractive precursors. However, it is difficult to assemble graphene into macroscopic cubes with good fatigue resistance performance. Here, we propose an efficient way to manufacture a lamellar-structural rGO aerogel with enhanced stiffness and deflection of lamellae, by using MXene as a rigidity additive. The addition of MXene (Ti3C2Tx) improves the mechanical and fatigue resistance properties of the aerogel, making it super compressible and elastic. The highly stable structure of the aerogel can withstand extremely high compressive strain of 90% and long-term compression at 50% strain for at least 10,000 cycles. The lamellar structure makes a great contribution to achieve good sensing performance including high linear sensitivity, low testing limit, wide testing strain range and quick response. These features make the MXene/rGO aerogel a promising sensing material for flexible wearable devices to monitor the subtle and obvious biosignals of the human body movement. [ABSTRACT FROM AUTHOR]

Methylobacterium sp. CLZ was isolated from soil contaminated with chemical wastewater. This strain simultaneously synthesizes Pyrroloquinoline quinone (PQQ), Coenzyme Q10 (CoQ10), and carotenoids by utilizing methanol as a carbon source. Comparative genomic analysis was performed for five Methylobacterium strains. As per the outcomes, the Methylobacterium CLZ strain showed the smallest genome size and the lowest number of proteins. Thus, it can serve as an ideal cell model for investigating the biological process of Methylobacterium and constructing genetically engineered Methylobacterium. The Methylobacterium CLZ strain's pqqL gene, which does not occur in other Methylobacterium strains but plays a crucial role in PQQ synthesis. This was a surprising finding for the study of PQQ biosynthesis in Methylobacterium. Methylobacterium sp. NI91 strain was generated by random mutagenesis of CLZ strain, and NI91 strain showed a 72.44% increase in PQQ yield. The mutation in the mxaJ gene involved in the methanol dehydrogenase (MDH) synthesis was identified through comparative genomic analysis of the whole genome of mutant strain NI91 and wild-type strain CLZ. The mxaJ gene was found to be upregulated in the NI91 strain. Thus, the up-regulation of the mxaJ gene could be correlated with the high yield of PQQ, and it could provide valuable clues for strain engineering to improve PQQ production. [ABSTRACT FROM AUTHOR]

The complexity of unsaturated soil means that its permeability coefficient and seepage law are important topics in soil mechanics and geotechnical engineering. In this study, a new type of equipment for measuring the seepage of unsaturated soil was used to study the steady seepage of unsaturated loess soil collected from northern Shaanxi province in China. The entire process of the steady seepage of unsaturated soil under different seepage hydraulic gradients was obtained, and the permeability coefficient in the steady seepage state was measured. When the soil water content was low, the soil moisture remained only in small pores or at the junction of soil particles, the effective seepage area of the sample was reduced, and the seepage path was extended. Therefore, the lower the water content, the smaller the permeability coefficient of unsaturated soil and the longer the time required for the seepage to reach a steady state. The matric suction of the unsaturated loess soil was measured under different water contents. With decreasing water content, water remained only in the smaller pores, which provided shrink films with a smaller radius of curvature. This allowed the shrink films to withstand a larger pore air pressure and transmit a smaller pore water pressure, so that the matric suction of the loess soil increased with decreasing soil water content. The Gardner model provided an accurate fit of how the matric suction varied with the volumetric water content of the unsaturated soil. The seepage velocity and seepage hydraulic gradient were correlated well with a linear relationship, indicating that the seepage law of unsaturated loess soil accords with Darcy's law. The experimental results show that the new unsaturated soil permeameter has good performance and controllability, thereby providing support for studying the steady seepage of unsaturated soil. [ABSTRACT FROM AUTHOR]

Rapid, high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae, which are responsible for algal blooms, such as red and green tides. In this study, we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously, namely Alexandrium tamarense, Gyrodinium instriatum, Heterosigma akashiwo, Karenia mikimotoi, Prorocentrum donghaiense, Prorocentrum minimum, Ulva compressa, Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection (LOD) of 0.5 ng of genomic DNA (orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether, 230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%, respectively, relative to conventional morphological methods. This indicated that this high-throughput, automatic, and specific method is well suited for the detection of algae in water samples. [ABSTRACT FROM AUTHOR]

Objectives: Recent data in human and mice suggest that monocyte chemokine receptors CX3CR1 and CCR2 are involved in the pathogenesis of atherosclerosis. Our previous study showed that hydrogen sulfide, a novel gaseous mediator hampered the progression of atherosclerosis in fat-fed apoE mice with downregulating CX3CR1 and CX3CL1 expressions. However, there is a paucity of information regarding the clinical association between endogenous HS metabolism and alterations of monocyte chemokine receptors in patients with cardiovascular disease. Therefore, in this study, we investigated circulating monocyte heterogeneity with differential expressions of CCR2 and CX3CR1 and its relevance to plasma HS level in patients with coronary artery disease (CAD). Methods: Sixty-three CAD patients with acute coronary syndrome (ACS, n = 46) or stable angina pectoris (SAP, n = 17) undergoing either percutaneous coronary intervention or coronary angiography and eleven non-CAD patients were enrolled in the study. Plasma levels of HS as well as chemokines (CCL2 and CX3CL1) and expressions of CCR2 and CX3CR1 on peripheral monocytes were measured. Results: It was found that plasma HS level was significantly reduced, whereas plasma CCL2 and CX3CL1 levels were substantially elevated in patients with ACS, as compared with patients with SAP or non-CAD patients. Furthermore, patients with ACS had significantly higher proportion of CD14CCR2CX3CR1 and CD14CCR2CX3CR1 monocytes but lower percentage of CD14CCR2CX3CR1 monocytes than SAP or non-CAD patients did. Lastly, plasma HS level showed a significantly negative correlation with the proportion of CD14CCR2CX3CR1 monocytes, but not other monocyte subsets. Conclusions: These data indicate that decreased endogenous HS production may predispose stable CAD patients to rupture of vulnerable plaque and thus to ACS, probably in relation to circulating monocyte phenotypic transformation with differential expressions of CCR2 and CX3CR1. [ABSTRACT FROM AUTHOR]

A continuum theoretical scheme for self equilibrium, self bending and symmetry lowering of nanofilms was obtained by considering surface elasticity, surface stress and the corresponding surface slice thickness. When surface stress and surface elasticity are both balance, the nanofilm is simply compressed (or expanded). When the surface stress or surface elasticity is imbalance, the nanofilm will bend. On the other hand, surface stress and surface elasticity imbalances induce a nanofilm to curl into a nanotube when the nanofilm is very thin. The surface stress and surface elasticity balances induce uniform in-plane strain (the overall film relaxation), while the vertical direction of the nanofilm relaxes reversely due to Poisson's effect. And then, the crystal lattice constants of in-plane and vertical directions are different from each other, the ratio of these two lattice constants decrease with film thickness increase. Hence, the symmetry of the nanofilm is lowered by the overall film relaxation. [ABSTRACT FROM AUTHOR]