Multiple heterologous M2 extracellular domains presented on virus-like particles confer broader and stronger M2 immunity than live influenza A virus infection

Kim, M.C.,Lee, J.S.,Kwon, Y.M.,O, E.,Lee, Y.J.,Choi, J.G.,Wang, B.Z.,Compans, R.W.,Kang, S.M. Elsevier/North-Holland 2013 Antiviral research Vol.99 No.3

The influenza M2 ectodomain (M2e) is poorly immunogenic and has some amino acid changes among isolates from different host species. We expressed a tandem repeat construct of heterologous M2e sequences (M2e5x) derived from human, swine, and avian origin influenza A viruses on virus-like particles (M2e5x VLPs) in a membrane-anchored form. Immunization of mice with M2e5x VLPs induced protective antibodies cross-reactive to antigenically different influenza A viruses and conferred cross protection. Anti-M2e antibodies induced by heterologous M2e5x VLPs showed a wider range of cross reactivity to influenza A viruses at higher levels than those by live virus infection, homologous M2e VLPs, or M2e monoclonal antibody 14C2. Fc receptors were found to be important for mediating protection by immune sera from M2e5x VLP vaccination. The present study provides evidence that heterologous recombinant M2e5x VLPs can be more effective in inducing protective M2e immunity than natural virus infection and further supports an approach for developing an effective universal influenza vaccine.

Graphene/M_xWO₃ (M=Na, K) nanohybrids with excellent electrical properties

Liu, B.,Yin, S.,Wu, X.,Wang, Y.,Huang, Y.,Wu, J.,Sekino, T.,Matsushita, J.,Lee, S.W.,Kobayashi, M.,Kakihana, M.,Sato, T. Pergamon Press ; Elsevier Science Ltd 2015 Carbon Vol.94 No.-

Graphene/M<SUB>x</SUB>WO<SUB>3</SUB> (M=Na, K) nanocomposites with different weight ratios were successfully synthesized using MBH<SUB>4</SUB> as a reducing agent in aqueous solution, followed by crystallization of amorphous precursors under calcination in H<SUB>2</SUB> (5vol.%)/N<SUB>2</SUB> atmosphere at 600<SUP>o</SUP>C. The coupled samples showed good shielding properties in NIR wavelength range together with certain visible lights transparency. The as-prepared tungsten bronze nanoparticles are homogeneously anchored on graphene sheets, and the graphene/tungsten bronze nanocomposite showed an enhanced electrical conductivity with good shielding properties in the NIR range together with certain visible lights transparency. With the increment of graphene amount in the composites, the contact between the graphene sheets was enhanced, and the M<SUB>x</SUB>WO<SUB>3</SUB> might enhance the charge transport properties of graphene by generating the short conductive path for electrons over the remained oxygenated functional groups. The synergistic effects could be observed in the composites. When 5wt.% or more graphene were composed into M<SUB>x</SUB>WO<SUB>3</SUB>, the hybrid composite showed the higher electrical conductivity than those of uncoupled graphene and tungsten bronze alone.

Groundwater Dynamics and Balance in the Western Part of Greater Kushtia District of Bangladesh

M. Nozibul Haque,Mumnunul Keramat,Shamsuddin Shahid,Morteza Mohsenipour,Xiao-Jun Wang 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.5

Groundwater dynamics and balance have been studied for the assessment of groundwater abstraction status in the western part of grater Kushtia district, Bangladesh using data from 28 groundwater level monitoring wells, 180 lithologs, and one rainfall station for the period 2001-2007. The groundwater levels in the study area were found to vary at a depth between 0.0 m and 9.34 m. During peak season of groundwater abstraction (pre-monsoon), the maximum and minimum groundwater level with respect to mean sea level (MSL) were found to vary from 9.36 to 11.3 m and 2.3 to 4.9 m, respectively, whereas in post-monsoon these values were found to vary from 13.2 to 15.6 m and 7.6 to 9.6 m, respectively. The groundwater flow in the area was driven by topography, directed from the northwest to the southeast. This study revealed a declining trend in groundwater table both in pre- and post-monsoon seasons in the area. It has also been noticed that the rate of declination is increasing with time. The volumetric analysis of groundwater also showed a net negative balance, which indicates overexploitation of groundwater. The study concluded that the unsustainable utilization of groundwater resources in the study area has caused depletion in groundwater table.

Fabrication of highly permeable thin-film nanocomposite forward osmosis membranes <i>via</i> the design of novel freestanding robust nanofiber substrates

Obaid, M.,Kang, Yesol,Wang, Sungrok,Yoon, Myung-Han,Kim, Chang-Min,Song, Jun-ho,Kim, In S. The Royal Society of Chemistry 2018 Journal of Materials Chemistry A Vol.6 No.25

<P>Although forward osmosis (FO) technology is considered to be a sustainable solution for the water and energy shortage, it has not been commercialized yet due to a few factors. Internal concentration polarization (ICP) is one of the most important barriers preventing the commercialization of the technology. To overcome the ICP obstacle, novel high-performance thin-film nanocomposite (TFN) membranes were successfully fabricated <I>via</I> interfacial polymerization on robust freestanding graphene oxide (GO) incorporated polyvinylidene fluoride (PVDF) nanofiber substrates. Compared to the pristine PVDF nanofiber substrate, the incorporation of GO (ranging from 0.1-15 wt%) significantly alters the chemical structure, porosity, wettability, morphology, and mechanical properties of the substrate, leading to an enhancement in the TFN membrane performance. The results showed that TFN5 (containing 5% GO) membrane possesses the lowest structural parameter of 85.5 μm (one of the best values in the literature), indicating a low internal concentration polarization (ICP) effect, resulting in a remarkably heightened water permeability (<I>A</I>; 2.96 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP>, enhanced by 167% compared to TFC). As a result, the membrane achieved the highest FO water flux at all draw solution concentrations (0.5-2 M NaCl), and the maximum FO water flux was 80.9 L m<SUP>−2</SUP> h<SUP>−1</SUP> (LMH) with a comparable specific salt flux (<I>J</I>s/<I>J</I>v) of 0.41 g L<SUP>−1</SUP> in the active layer facing the deionized feed water (AL-FS) when 2 M NaCl was applied as a draw solution. Interestingly, TFN5 was found to be the strongest material, with outstanding flexibility and strength over that of the TFC membrane. Furthermore, it showed high stability and durability during long-term FO operation. More importantly, the interaction mechanism between PVDF and GO was proposed schematically. Overall, the obtained results show highly efficient and promising TFN membranes that may overcome the drawbacks of the aforementioned FO membranes.</P>

Is iron unique in promoting electrical conductivity in MOFs?

Sun, L.,Hendon, C.,Park, S.,Tulchinsky, Y.,Wan, R.,Wang, F.,Walsh, A.,Dinca, M. Royal Society of Chemistry 2017 Chemical Science Vol.8 No.6

<P>Identifying the metal ions that optimize charge transport and charge density in metal-organic frameworks is critical for systematic improvements in the electrical conductivity in these materials. In this work, we measure the electrical conductivity and activation energy for twenty different MOFs pertaining to four distinct structural families: M-2(DOBDC)(DMF)(2) (M = Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+); H4DOBDC = 2,5-dihydroxybenzene-1,4-dicarboxylic acid; DMF = N, N-dimethylformamide), M-2(DSBDC)(DMF)(2) (M = Mn2+, Fe2+; H4DSBDC = 2,5-disulfhydrylbenzene-1,4-dicarboxylic acid), M2Cl2(BTDD)(DMF)(2) (M = Mn2+, Fe2+, Co2+, Ni2+; H2BTDD = bis(1H-1,2,3-triazolo[4,5-b],[40,50-i]dibenzo[1,4]dioxin), and M(1,2,3-triazolate)(2) (M = Mg2+, Mn2+, Fe2+, Co2+, Cu2+, Zn2+, Cd2+). This comprehensive study allows us to single-out iron as the metal ion that leads to the best electrical properties. The iron-based MOFs exhibit at least five orders of magnitude higher electrical conductivity and significantly smaller charge activation energies across all different MOF families studied here and stand out materials made from all other metal ions considered here. We attribute the unique electrical properties of iron-based MOFs to the high-energy valence electrons of Fe2+ and the Fe3+/2+ mixed valency. These results reveal that incorporating Fe2+ in the charge transport pathways of MOFs and introducing mixed valency are valuable strategies for improving electrical conductivity in this important class of porous materials.</P>

Characteristics and composition of atmospheric aerosols in Phimai, central Thailand during BASE-ASIA

Li, C.,Tsay, S.C.,Hsu, N.C.,Kim, J.Y.,Howell, S.G.,Huebert, B.J.,Ji, Q.,Jeong, M.J.,Wang, S.H.,Hansell, R.A.,Bell, S.W. Pergamon Press ; Elsevier [distribution] 2013 Atmospheric environment Vol.78 No.-

Comprehensive measurements of atmospheric aerosols were made in Phimai, central Thailand (15.183<SUP>o</SUP>N, 102.565<SUP>o</SUP>E, elevation: 206 m) during the BASE-ASIA field experiment from late February to early May in 2006. The observed aerosol loading was sizable for this rural site (mean aerosol scattering: 108 +/- 64 Mm<SUP>-1</SUP>; absorption: 15 +/- 8 Mm<SUP>-1</SUP>; PM<SUB>10</SUB> concentration: 33 +/- 17 μg m<SUP>-3</SUP>), and dominated by submicron particles. Major aerosol compounds included carbonaceous (OC: 9.5 +/- 3.6 μg m<SUP>-3</SUP>; EC: 2.0 +/- 2.3 μg m<SUP>-3</SUP>) and secondary species (SO<SUB>4</SUB><SUP>2-</SUP>: 6.4 +/- 3.7 μg m<SUP>-3</SUP>, NH<SUB>4</SUB><SUP>+</SUP>: 2.2 +/- 1.3 μg m<SUP>-3</SUP>). While the site was seldom under the direct influence of large forest fires to its north, agricultural fires were ubiquitous during the experiment, as suggested by the substantial concentration of K<SUP>+</SUP> (0.56 +/- 0.33 μg m<SUP>-3</SUP>). Besides biomass burning, aerosols in Phimai during the experiment were also strongly influenced by industrial and vehicular emissions from the Bangkok metropolitan region and long-range transport from southern China. High humidity played an important role in determining the aerosol composition and properties in the region. Sulfate was primarily formed via aqueous phase reactions, and hygroscopic growth could enhance the aerosol light scattering by up to 60%, at the typical morning RH level of 85%. The aerosol single scattering albedo demonstrated distinct diurnal variation, ranging from 0.86 +/- 0.04 in the evening to 0.92 +/- 0.02 in the morning. This experiment marks the first time such comprehensive characterization of aerosols was made for rural central Thailand. Our results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow.

Activation of Neuronal Nitric Oxide Synthase by M2 Muscarinic Receptors Associated with a Small Increase in Intracellular Calcium

Wang, Shou-Zhen,Lee, Seok-Yong,Zhu, Sheng-Zu,Wotta, Diane R.,Parsons, Ann M.,El-Fakahany, Esam E. 성균관대학교 약학연구소 1998 成均藥硏論文集 Vol.10 No.1

We investigated the coupling of the M2 muscarinic acetylcholine receptors expressed in Chinese hamster ovary cells to activation of neuronal nitric oxide(NO) synthase. Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an indirect measure of the generation of NO in Chinese hamster ovary cells. The muscarinic agonist carbachol induced marked time-and concentration-dependent enhancement of the activity of NO synthase. Activation of neuronal NO synthase by M2 muscarinic receptors was associated with a small increase in the concentration of intracellular Ca^2+. These data suggest the presence of alternate mechanisms of activation of neuronal NO synthase which might be operative in the absence of large changes in the concentration of cellular Ca^2+. These findings help to understand the mechanisms of activation of NO synthase.

Novel chromenedione derivatives displaying inhibition of protein tyrosine phosphatase 1B (PTP1B) from Flemingia philippinensis

Wang, Y.,Yuk, H.J.,Kim, J.Y.,Kim, D.W.,Song, Y.H.,Tan, X.F.,Curtis-Long, M.J.,Park, K.H. Pergamon Press 2016 Bioorganic & medicinal chemistry letters Vol.26 No.2

Protein tyrosine phosphatase 1B (PTP1B) is an important target to treat obesity and diabetes due to its key roles in insulin and leptin signaling. The MeOH extracts of the root bark of Flemingia philippinensis yielded eight inhibitory molecules (1-8) capable of targeting PTP1B. Three of them were identified to be novel compounds, philippin A (1), philippin B (2), and philippin C (3) which have a rare 3-phenylpropanoyl chromenedione skeleton. The other compounds (4-8) were known prenylated isoflavones. All compounds (1-8) inhibited PTP1B in a dose dependent manner with IC<SUB>50</SUB>s ranging between 2.4 and 29.4μM. The most potent compound emerged to be prenylated isoflavone 5 (IC<SUB>50</SUB>=2.4μM). In kinetic studies, chromenedione derivatives (1-3) emerged to be reversible, competitive inhibitors, whereas prenylated isoflavones (5-8) were noncompetitive inhibitors.

Fabrications and dielectric performances of novel composites: Calcium copper titanate / Polyvinylidene fluoride

Wang J.J.,Deng Q.J.,He Y.Y.,Feng Y.N.,Kang M.P.,Duan X.L.,Yang Y.L. 한국물리학회 2022 Current Applied Physics Vol.39 No.-

CCTO (Calcium copper titanate) powder as inorganic filler was synthesized by the Sol-gel method firstly. CCTO/ PVDF (Polyvinylidene fluoride) composite was fabricated by solution mixing based on high temperature resistance of PVDF and insulated property of CCTO. The composite of CCTO/PVDF were characterized by X-ray diffraction, Fourier Transform infrared spectroscopy, Scanning Electron Microscope and impedance analysis. The results showed that the addition of CCTO and increasing in its content did not affect the phase- and microstructure of the composites,but the increase of CCTO content can induce the generation of C–F new bonds. PVDF/CCTO composites were enhanced in performance of thermal and frequency-depended stability with increasing in the fraction of CCTO. The dielectric constant of CCTO/PVDF composite materials with 50% CCTO achieved to a maximum value of 50 almost, which is 5 times higher the pure PVDF. The conductivity felled into 10-8 to 10-1 S m-1 during the frequency of 102–108 Hz. The composite material would be expected to be applied in the field of integrated circuit.

Ground-based Parallax Confirmed by<i>Spitzer</i>: Binary Microlensing Event MOA-2015-BLG-020

Wang, Tianshu,Zhu, Wei,Mao, Shude,Bond, I. A.,Gould, A.,Udalski, A.,Sumi, T.,Bozza, V.,Ranc, C.,Cassan, A.,Yee, J. C.,Han, C.,Abe, F.,Asakura, Y.,Barry, R.,Bennett, D. P.,Bhattacharya, A.,Donachie, M. American Astronomical Society 2017 The Astrophysical journal Vol.845 No.2

<P>We present the analysis of the binary gravitational microlensing event MOA-2015-BLG-020. The event has a fairly long timescale (similar to 63 days) and thus the light curve deviates significantly from the lensing model that is based on the rectilinear lens-source relative motion. This enables us to measure the microlensing parallax through the annual parallax effect. The microlensing parallax parameters constrained by the ground-based data are confirmed by the Spitzer observations through the satellite parallax method. By additionally measuring the angular Einstein radius from the analysis of the resolved caustic crossing, the physical parameters of the lens are determined. It is found that the binary lens is composed of two dwarf stars with masses M-1= 0.606 +/- 0.028M(circle dot) and M-2= 0.125 +/- 0.006 M-circle dot in the Galactic disk. Assuming that the source star is at the same distance as the bulge red clump stars, we find the lens is at a distance D-L = 2.44 +/- 0.10 kpc. We also provide a summary and short discussion of all of the published microlensing events in which the annual parallax effect is confirmed by other independent observations.</P>