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Three-dimensional graphene (3D-GN)/Cu/Fe3O4 composite support materials were synthesized by a modified chemical reduction method using graphene oxide precursor. A 3D-GN/Cu/Fe3O4 biosensor was prepared by coating the electrode with laccase. The electrochemical properties of the biosensor were investigated by cyclic voltammetry (CV) and differential pulse voltammetry using potassium ferricyanide, phosphate-buffered saline (PBS) solution, and bisphenol A (BPA) solution. The current response of 3D-GN/Cu/Fe3O4 biosensors presents a remarkable sensitivity based on CV. The linear range of BPA is 7.2–18 μM using differential pulse voltammetry in PBS solution (pH = 4.0). A linear fitting equation of the laccase biosensor was observed for the current response as a function of BPA concentration. The detection limit was decreased to 1.7 μM. The detection approach herein turns out to be highly sensitive, has a wide linear range, and exhibits excellent stability.
Annexin A2 (ANXA2) is reported to be associated with cancer development. To investigate the roles ANXA2 plays during the development of cancer, the RNAi method was used to inhibit the ANXA2 expression in caco2 (human colorectal cancer cell line) and SMMC7721 (human hepatocarcinoma cell line) cells. The results showed that when the expression of ANXA2 was efficiently inhibited, the growth and motility of both cell lines were significantly decreased, and the development of the motility relevant microstructures, such as pseudopodia, filopodia, and the polymerization of microfilaments and microtubules were obviously inhibited. The cancer cell apoptosis was enhanced without obvious significance. The possible regulating pathway in the process was also predicted and discussed. Our results suggested that ANXA2 plays important roles in maintaining the malignancy of colorectal and hepatic cancer by enhancing the cell proliferation, motility, and development of the motility associated microstructures of cancer cells based on a possible complicated signal pathway.
Compared with end pumping fiber combiner, one of the advantages for side pumping combiner is the unlimited pumping points, which means multi-point or cascaded side pumping can be realized. However, the loss mechanism of the cascaded structure is rarely discussed. In this paper, we present the numerical and experimental investigation about the loss mechanism of a two-stage-cascaded side pumping combiner based on tapered-fused technique. The influence of loss mechanism on the coupling efficiency and thermal load of the fiber coating is analyzed according to simulations and experiments with different tapering ratios for the first stage. Based on the analysis, a cascaded component with total pump coupling efficiency of 96.4% handling a pump power of 1088 W is achieved by employing 1018 nm fiber laser as the pump source. Future work to further improve the performance of a cascaded side pumping combiner is discussed and prospected.
Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid β-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid β-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.
In studying Galactic open clusters based on LAMOST DR3, we deliberately selected several nearby cluster, which have relatively large projection area and reliable proper motion measurements. For each cluster, we firstly determine the typical proper motion distribution profiles in the cluster-core and the outskirt region, respectively, and perform field-star decontamination on the cluster area. We then calculate kinematic membership probability for each star in the cluster area and cross-match the highly probable members with LAMOST DR3 spectral catalog. Based on enhanced signal of cluster-member radial velocity distribution emerging from the whole field, we have also obtained reliable radial velocity membership probability for each star. Finally, we perform isochrones fitting with MCMC technique to study basic properties of these cluster, including age, metallicity, and distance modulus.
Graphene nanoribbons as a quasi-one-dimensional form of graphene has attracted intensive attention in energy related devices. Upon oxidation and cutting of multiwall carbon nanotubes (MWCNTs), highly dispersive graphene oxide nanoribbons (GONRs) were obtained, on which Zn2+ and Sn4+ can be homogenously deposited. The reduced graphene oxide nanoribbons (rGONRs)/Zn2SnO4 composite with a homogeneous distribution of nanoparticles on the nanoribbons have been prepared through facile in situ chemical co-reduction process. It is worth noting that the size of Zn2SnO4 particles tightly dispersed on rGONRs is about 15 nm. Benefit from the introduction of rGONRs, the specific surface area and electrode conductivity of rGONRs/Zn2SnO4 can both be effectively enhanced. The as-prepared rGONRs/Zn2SnO4 as anode material for lithium-ion batteries displays desirable electrochemical performance (727.2 mA h/g after 50 cycles at the current density of 100 mA/g), which is mainly attributed to the uniformly distributed Zn2SnO4 nanoparticles and the immobilizing and conducting effects of rGONRs.
In this paper, we focus on studying the high energy emission of GRB 160625B. The lightcurve of prompt emission is composed of three episodes: short-soft precursor, hard main burst, and possible long extended emission. The spectra of first and third episode can be fitted by a multi-color blackbody and cutoff power-law model, respectively. However, the spectrum of second episode was contributed by both multi-color blackbody and cutoff power-law. One can estimate the Lorenz factor of jet of first two episodes by invoking photosphere model as Γ0 ~ 175 and 1694, respectively. It suggests that the ejecta of this case evolved from photosphere dominated initially to internal shock later. On the other hand, the optical emission is very bright during the second episode, which is likely a prompt optical emission. Finally, a more shallower normal decay segment appeared, which is consistent with standard external shock model.
Feeding regime is an important concern for sea urchin aquaculture. However, optimal feed regimes have not been established for land-based sea urchin ventures using a formulated feed. In this study, we investigated the effects of short-term continuous and intermittent feeding regimes on food consumption, growth, gonad production and quality of the sea urchin Strongylocentrotus intermedius (54.90 ± 2.28 mm of test diameter) fed a formulated feed. The results showed that (1) compared with initial conditions, all involved traits except a* (test diameter, test height, body weight, gonad weight, gonad index, gonad moisture, L* and b*) showed significant increase at the end of the experiments; (2) only the longest term feed regime tested in this trial (S2) significantly negatively affected growth and gonad production of S. intermedius fed a formulated feed; (3) there was a trend but this was not significant for inhibiting gonad development of S. intermedius in intermittent feeding regimes and there was no change in the gonad colour and sweetness; (4) S0.5 (fasting half day and then feeding half day) is the optimal intermittent feeding regime for S. intermedius fed a formulated feed. To our knowledge, the present study is the first report of finding an effective intermittent feeding regime for land-based cultured sea urchins of relatively large size, and thus has direct application potential in the field of aquaculture.
The objective of this study was to build a database to collect infectious disease information at the scene of a disaster through the use of 128 epidemiological questionnaires and 47 types of options, with rapid acquisition of information regarding infectious disease and rapid questionnaire customization at the scene of disaster relief by use of a personal digital assistant (PDA).
SQL Server 2005 (Microsoft Corp, Redmond, WA) was used to create the option database for the infectious disease investigation, to develop a client application for the PDA, and to deploy the application on the server side. The users accessed the server for data collection and questionnaire customization with the PDA.
A database with a set of comprehensive options was created and an application system was developed for the Android operating system (Google Inc, Mountain View, CA). On this basis, an infectious disease information collection system was built for use at the scene of disaster relief. The creation of an infectious disease information collection system and rapid questionnaire customization through the use of a PDA was achieved.
This system integrated computer technology and mobile communication technology to develop an infectious disease information collection system and to allow for rapid questionnaire customization at the scene of disaster relief. (Disaster Med Public Health Preparedness. 2017;11:668–673)
In this work, we present a set of M-type star candidates selected from the LAMOST DR1. A discrimination method with the spectral index diagram is used to separate M giants and M dwarfs. Then, we have successfully assembled a set of M giants templates from M0 to M6, using the spectra identified from the LAMOST spectral database. After combining the M dwarf templates in Zhong et al. (2015a) and the new created M giant templates, we use the M-type spectral library to perform the template-fit method to classify and identify M-type stars in the LAMOST DR1. A catalog of M-type star candidates including 8639 M giants and 101690 M dwarfs/subdwarfs is provided. As an additional results, we also present other fundamental parameters like proper motion, photometry, radial velocity and spectroscopic distance.
This paper presents a novel metamaterial constructed with wires, spheres and hollow slabs (WSHS), which simultaneously exhibits negative permittivity and permeability. An electromagnetic wave simulation is performed based on the proposed metamaterial and shows that a negative refractive index is achieved for this metamaterial. Adjusting the lattice constant of the unit cell is an easy way to manipulate the frequency of negative index of this structure. A left-hand material prism is designed composed of metamaterial unit cells and the simulation on the proposed prism proves the left-hand behavior of the designed metamaterial.
Cytosol Ca2+ overload plays a vital role in ischemic neuronal damage, which is largely contributed by the Ca2+ influx through L-type voltage-gated calcium channels (L-VGCCs) and N-methyl-D-aspartate (NMDA) type glutamate receptors. In this article, L-VGCCs were activated by depolarization to investigate the cross-talk between NMDA receptors and L-VGCCs.
Depolarization was induced by 20 minutes incubation of 75 mM KCl in cultured rat cortical neuron. Apoptosis-like neuronal death was detected by DAPI staining. Tyrosine phosphorylation of NMDA receptor subunit 2A (NR2A), interactions of Src and NR2A were detected by immunoblot and immunoprecipitation.
Depolarization induced cortical neuron apoptosis-like cell death after 24 hours of restoration. The apoptosis was partially inhibited by 5 mM EGTA, 100 μM Cd2+, 10 μM nimodipine, 100 μM genistein, 20 μM MK-801, 2 μM PP2 and combined treatment of nimodipine and MK-801. NR2A tyrosine phosphorylation increased after depolarization, and the increase was inhibited by the drugs listed above. Moreover, non-receptor tyrosine kinase Src bound with NR2A after depolarization and restoration. The binding was also inhibited by the drugs listed above.
The results indicated that depolarization-induced neuronal death might be due to extracellular Ca2+ influx through L-VGCCs and subsequently Src activationmediated NR2A tyrosine phosphorylation.
Background: The molecular pathogenesis of depression and psychopharmacology of antidepressants remain elusive. Recent hypotheses suggest that changes in neurogenesis and plasticity may underlie the aetiology of depression. The hippocampus is affected by depression and shows neuronal remodelling during adulthood.
Objective: The present study on the adult rat hippocampus, was to evaluate the dose-related effects of chronic venlafaxine on the expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cyclic-AMP response element binding protein (pCREB).
Methods: Sprague-Dawley rats were exposed to a variety of chronic unpredictable stressors (CUSs) to establish a depression model. Rats were treated for either 14 or 28 days with venlafaxine (5 and 10 mg/kg, respectively). The hippocampal expression of pCREB and BDNF mRNA and protein was assessed by using immunohistochemistry, western blotting and reverse transcription polymerase chain reaction (RT-PCR).
Results: Rats subjected to CUS procedure consumed less sucrose solution compared with non-stressed rats. The CUS influenced exploratory activity resulting in a reduction of the motility counts. Chronic low dose (5 mg/kg, 14 and 28 days), but not high dose (10 mg/kg, 14 and 28 days) of venlafaxine treatment increased the expression of pCREB and BDNF mRNA and protein in the CUS rat hippocampus.
Conclusion: Neuronal plasticity-associated proteins such as pCREB and BDNF play an important role both in stress-related depression and in antidepressant effect.
Silicon-germanium (Si1−xGex:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH4 and GeH4 and measured during growth using real time spectroscopic ellipsometry. A two-layer virtual interface analysis has been applied to study the structural evolution of Si:H films prepared in multistep processes utilizing alternating intermediate and low H2-dilution material layers, which have been designed to produce predominately amorphous films with a controlled distribution of microcrystalline particles. The compositional evolution of alloy-graded a-Si1−xGex:H has been studied as well using similar methods. In each case, depth profiles of microcrystalline content, fμc, or Ge content, x, have been extracted. Additionally, real time spectroscopic ellipsometry has been used to monitor post-deposition exposure of a-Si:H, a-Si1−xGex:H, and a-Ge:H films to a hydrogen plasma in situ in order to determine sub-surface amorphous film modification similar to that which would occur when a highly H2-diluted layer is deposited on a layer prepared with lower dilution. These analyses provide guidance for enhanced performance of Si:H based solar cells, through controlled bandgap grading using compositionally graded amorphous binary alloys (a-Si1−xGex:H) or the incorporation of controlled fractions of microcrystallites into bulk amorphous i-layer materials, and by providing a fundamental understanding of the modification of component layers during the deposition of subsequent layers in multilayer stacks.
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