DNA capturing machinery through spore‐displayed proteins

Park, T.J.,Lee, S.J.,Pan, J.&#x2010,G.,Jung, H.&#x2010,C.,Park, J.Y.,Park, J.P.,Lee, S.Y. Blackwell Publishing Ltd 2011 Letters in applied microbiology Vol.53 No.4

<P><B>Abstract</B></P><P><B>Aims: </B> The purpose of this study was to develop a general method for the facile development of a new DNA biosensor which utilizes streptavidin‐displayed spores as a molecular machinery.</P><P><B>Methods and Results: </B> Fluorescence spectroscopy was used as a monitoring tool for the streptavidin displayed on the surface of <I>Bacillus thuringiensis</I> spores and as a diagnosis method for DNA detection. As a proof‐of‐concept, four pathogenic bacteria including <I>Pseudomonas aeruginosa</I>, <I>Acinetobacter baumannii</I>, <I>Escherichia coli</I> and <I>Klebsiella pneumonia</I> were used for the detection of pathogenic species. In addition, a set of mutant variants of Wilson’s disease were also used for the detection of single nucleotide polymorphism (SNP) in this system.</P><P><B>Conclusions: </B> This strategy, utilizing streptavidin‐displayed spores, is capable of capturing DNA targets for the detection of pathogenic bacteria and for mutation analysis in Wilson’s disease.</P><P><B>Significance and Impact of the Study: </B> This approach could be useful as a simple platform for developing sensitive spore‐based biosensors for any desired DNA targets in diagnostic applications.</P>

Response of plasma rotation to resonant magnetic perturbations in J-TEXT tokamak

Yan, W,Chen, Z Y,Huang, D W,Hu, Q M,Shi, Y J,Ding, Y H,Cheng, Z F,Yang, Z J,Pan, X M,Lee, S G,Tong, R H,Wei, Y N,Dong, Y B IOP 2018 Plasma physics and controlled fusion Vol.60 No.3

<P>The response of plasma toroidal rotation to the external resonant magnetic perturbations (RMP) has been investigated in Joint Texas Experimental Tokamak (J-TEXT) ohmic heating plasmas. For the J-TEXT’s plasmas without the application of RMP, the core toroidal rotation is in the counter-current direction while the edge rotation is near zero or slightly in the co-current direction. Both static RMP experiments and rotating RMP experiments have been applied to investigate the plasma toroidal rotation. The core toroidal rotation decreases to lower level with static RMP. At the same time, the edge rotation can spin to more than 20 km s<SUP>−1</SUP> in co-current direction. On the other hand, the core plasma rotation can be slowed down or be accelerated with the rotating RMP. When the rotating RMP frequency is higher than mode frequency, the plasma rotation can be accelerated to the rotating RMP frequency. The plasma confinement is improved with high frequency rotating RMP. The plasma rotation is decelerated to the rotating RMP frequency when the rotating RMP frequency is lower than the mode frequency. The plasma confinement also degrades with low frequency rotating RMP.</P>

Passive Q-switching of microchip lasers based on Ho:YAG ceramics

Lan, R.,Loiko, P.,Mateos, X.,Wang, Y.,Li, J.,Pan, Y.,Choi, S. Y.,Kim, M. H.,Rotermund, F.,Yasukevich, A.,Yumashev, K.,Griebner, U.,Petrov, V. Optical Society of America 2016 Applied Optics Vol.55 No.18

<P>A Ho:YAG ceramic microchip laser pumped by a Tm fiber laser at 1910 nm is passively Q-switched by single-and multi-layer graphene, single-walled carbon nanotubes (SWCNTs), and Cr2+:ZnSe saturable absorbers (SAs). Employing SWCNTs, this laser generated an average power of 810 mW at 2090 nm with a slope efficiency of 68% and continuous wave to Q-switching conversion efficiency of 70%. The shortest pulse duration was 85 ns at a repetition rate of 165 kHz, and the pulse energy reached 4.9 mu J. The laser performance and pulse stability were superior compared to graphene SAs even for a different number of graphene layers (n = 1 to 4). A model for the description of the Ho:YAG laser Q-switched by carbon nanostructures is presented. This modeling allowed us to estimate the saturation intensity for multi-layered graphene and SWCNT SAs to be 1.2 +/- 0.2 and 7 +/- 1 MW/cm(2), respectively. When using Cr2+:ZnSe, the Ho:YAG microchip laser generated 11 ns/25 mu J pulses at a repetition rate of 14.8 kHz. (C) 2016 Optical Society of America</P>

Enhanced ferroelectric, piezoelectric and dielectric properties of (1-x)CaBi2Nb2O9-xBaZr0.2Ti0.8O3 high-temperature piezoelectric composite ceramics

Pan C.B.,Zhao G.C.,Li S.M.,Shu M.F.,Wu J.,Wang J.M.Z.,Yin L.H.,Song W.H.,Zhu X.B,Yang J.,Sun Y.P. 한국물리학회 2022 Current Applied Physics Vol.34 No.-

Among Aurivillius layer-structured materials, CaBi2Nb2O9 is a best potential candidate for ultrahigh-temperature applications because of its highest Curie temperature of about 940 ◦C. In this paper, (1-x)CaBi2Nb2O9- xBaZr0.2Ti0.8O3 composite ceramics were prepared by conventional solid-state sintering method. The dielectric results show that the introduction of BaZr0.2Ti0.8O3 not only increases the permittivity of the material, but also reduces its dielectric loss. The optimum electrical properties were obtained in the x = 0.01 sample with piezoelectric coefficient (d33) of 15.1 pC/N and high ferroelectric remnant polarization (Pr) of 9.9 μC/cm2. Furthermore, the composite samples show good thermal depoling performance, the d33 of the x = 0.01 sample is 13.8 pC/N, which is about 91% of the initial value after depoling at 800 ◦C. Therefore, (1-x)CaBi2Nb2O9- xBaZr0.2Ti0.8O3 is one of the candidates for high temperature piezoelectric materials.

Tailoring the Impact Toughness of Sintered NdFeB Magnets via Surface Coating

X. G. Cui,J. X. Pan,C. Y. Cui,P. Mei,X. H. Wang,C. Fang,T. Y. Ma,C. Wang,X. C. Peng 한국자기학회 2018 Journal of Magnetics Vol.23 No.1

Metallic coating by electroplating is commonly attractive for improving the corrosion resistance of sintered NdFeB magnets. However, its tailoring of mechanical characteristics for sintered NdFeB magnets has been seldom concerned. Herein, the impact toughnesses of sintered NdFeB magnets with various metallic coatings (Ni or Ni/Sn) were comparatively investigated. The results indicate that the impact toughnesses of sintered NdFeB magnets are both improved by Ni coating and Ni/Sn bilayer coating. And Ni/Sn bilayer coating exhibits more enhancement of the impact toughness, increased by 41.6% compared with the original magnet. Moreover, the microstructural observations of the metallic coatings and the fracture were conducted, and the enhanced mechanism of impact toughness for the magnet is analyzed. These findings may provide a reference for toughening the brittle materials.

Analysis on the Voltage Stability and the Allowed Penetration Capacity of Distributed Generations in Yuhang Power Grid

X. Hu,X. Zhang,X. Lou,X. Meng,J. Zhang,T. Li,S. Pan 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

The increasing amount of the integration of distributed generations (DG) will bring about some adverse effects on the static and transient voltage stability, or even threaten the reliability and the safety of the whole power grid. The integration capacity of DGs is the main fact that contributes to the impact on the voltage stability. As DGs are connected to the grid through electronic interface, different kinds of control methods affect voltage stability significantly as well. This work mainly focuses on the DG integration to Yuhang power grid, and the outside part of this grid can be equivalent to a Thevenin circuit. The analytic expressions of the voltage and the power penetration rate at the DG connected node are derived. On this basis, the stability characteristics of the load voltage under different DG penetration rates are analyzed. Moreover, the effects of different reactive power control strategies on voltage static stability are compared with each other, and the transient voltage stabilities under different DG penetration rates are also discussed. Finally, the allowed penetration rate for Yuhang power grid is determined after checking the static and transient stability. The results show that the system can support more loads if the penetration of DG is increased appropriately.

Cyst-Like Osteolytic Formations in Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) Augmented Sheep Spinal Fusion

Pan, H.C.,Lee, S.,Ting, K.,Shen, J.,Wang, C.,Nguyen, A.,Berthiaume, E.A.,Zara, J.N.,Turner, A.S.,Seim, H.B.,Kwak, J.H.,Zhang, X.,Soo, C. American Association of Pathologists and Bacteriol 2017 The American journal of pathology Vol.187 No.7

<P>Multiple case reports using recombinant human bone morphogenetic protein-2 (rhBMP-2) have reported complications. However, the local adverse effects of rhBMP-2 application are not well documented. In this report we show that, in addition to promoting Lumbar spinal fusion through potent osteogenic effects, rhBMP-2 augmentation promotes local cyst-like osteolytic formations in sheep trabecular bones that have undergone anterior lumbar interbody fusion. Three months after operation, conventional computed tomography showed that the trabecular bones of the rhBMP-2 application groups could fuse, whereas no fusion was observed in the control group. Micro computed tomography analysis revealed that the core implant area's bone volume fraction and bone mineral density increased proportionately with rhBMP-2 dose. Multiple cyst-Like bone voids were observed in peri-implant areas when using rhBMP2 applications, and these sites showed significant bone mineral density decreases in relation to the unaffected regions. Biomechanically, these areas decreased in strength by 32% in comparison with noncystic areas. Histologically, rhBMP-2 affected void sites had an increased amount of fatty marrow, thinner trabecular bones, and significantly more adiponectin- and cathepsin K-positive cells. Despite promoting successful fusion, rhBMP-2 use in clinical applications may result in local adverse structural alterations and compromised biomechanical changes to the bone.</P>

Interaction of JMJD6 with single-stranded RNA

Hong, X.,Zang, J.,White, J.,Wang, C.,Pan, C.-H.,Zhao, R.,Murphy, R.C.,Dai, S.,Henson, P.,Kappler, J.W. National Academy of Sciences 2010 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.107 No.33

Improvement of OMI ozone profile retrievals in the upper troposphere and lower stratosphere by the use of a tropopause-based ozone profile climatology

Bak, J.,Liu, X.,Wei, J. C.,Pan, L. L.,Chance, K.,Kim, J. H. Copernicus GmbH 2013 Atmospheric measurement techniques Vol.6 No.9

<P><p><strong>Abstract.</strong> Motivated by the need of obtaining a more accurate global ozone distribution in the upper troposphere and lower stratosphere (UTLS), we have investigated the use of a tropopause-based (TB) ozone climatology in ozone profile retrieval from the Ozone Monitoring Instrument (OMI). Due to the limited vertical ozone information in the UTLS region from OMI backscattered ultraviolet radiances, better climatological a priori information is important for improving ozone profile retrievals. We present the new TB climatology and evaluate the result of retrievals against previous work. The TB climatology is created using ozonesonde profiles from 1983 through 2008 extended with climatological ozone data above sonde burst altitude (~35 km) with the corresponding temperature profiles used to identify the thermal tropopause. The TB climatology consists of the mean states and 1σ standard deviations for every month for each 10° latitude band. Compared to the previous TB climatology by Wei et al. (2010), three additional processes are applied in deriving our climatology: (1) using a variable shifting offset to define the TB coordinate, (2) separating ozonesonde profiles into tropical and extratropical regimes based on a threshold of 14 km in the thermal tropopause height, and (3) merging with an existing climatology from 5-10 km above the tropopause. The first process changes the reference of profiles to a variable position between local and mean tropopause heights within ±5 km of the tropopause and to the mean tropopause elsewhere. The second helps to preserve characteristics of either tropical or extratropical ozone structures depending on tropopause height, especially in the subtropical region. The third improves the climatology above ozonesonde burst altitudes and in the stratosphere by using climatology derived from many more satellite observations of ozone profiles. With aid from the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) tropopause height, the new climatology and retrieval can better represent the dynamical variability of ozone in the tropopause region. The new retrieval result demonstrates significant improvement of UTLS ozone, especially in the extratropical UTLS, when evaluated using ozonesonde measurements and the meteorological data. The use of TB climatology significantly enhances the spatial consistency and the statistical relationship between ozone and potential vorticity/tropopause height in the extratropical UTLS region. Comparisons with ozonesonde measurements show substantial improvements in both mean biases and their standard deviations over the extratropical lowermost stratosphere and upper troposphere. Overall, OMI retrievals with the TB climatology show improved ability in capturing ozone gradients across the tropopause found in tropical/extratropical ozonesonde measurements.</p> </P>

100KW DC Arc Plasma of CVD System for Low Cost Large Area Diamond Film Deposition

Lu, F.X.,Zhong, G.F.,Fu, Y.L.,Wang, J.J.,Tang, W.Z.,Li, G.H.,Lo, T.L.,Zhang, Y.G.,Zang, J.M.,Pan, C.H.,Tang, C.X.,Lu, Y.P. The Korean Ceramic Society 1996 The Korean journal of ceramics Vol.2 No.4

In the present paper, a new type of DC arc plasma torch is disclosed. The principles of the new magnetic and fluid dynamic controlled large orifice long discharge tunnel plasma torch is discussed. Two series of DC Plasma Jet diamond film deposition equipment have been developed. The 20kW Jet equipped with a $\Phi$70 mm orifice torch is capable of deposition diamond films at a growth rate as high as 40$\mu\textrm{m}$/h over a substrate area of $\Phi$65 mm. The 100kW high power Jet which is newly developed based on the experience of the low power model is equipped with a $\Phi$120 mm orifice torch, and is capable of depositing diamond films over a substrate area of $\Phi$110 mm at growth rate as high as 40 $\mu\textrm{m}$/h, and can be operated at gas recycling mode, which allows 95% of the gases be recycled. It is demonstrated that the new type DC plasma torch can be easily scaled up to even higher power Jet. It is estimated that even by the 100kW Jet, the cost for tool grade diamond films can be as low as less than $4/carat.