Ferroelectricity in Ternary II-VI Compounds

D. J. Fu,이동진,W.C. Lee,J. C. Lee,T. W. Kang 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.3

This paper presents a study on polarization hysteresis, current-voltage characteristics, and temperature dependence of polarization and capacitance of CdZnTe. The polarization-electric eld measurement shows a polarization of 0.6C/cm2 in CdZnTe, and the hysteresis is signicantly in uenced by carriers. The capacitance of CdZnTe consists of ferroelectric and depletion components. Electrical conduction in CdZnTe is modulated by the polarization, leading to hysteresis in the current-voltage characteristics. The polarization decreases in a continuous and diusive manner. Temperature dependent capacitance measurement demonstrates a maximum capacitance around 90C. Fitting of the capacitance data with the Curie-Weiss law shows the occurrence of a second-order type phase transition.

Nuclear Receptor-Induced Chromosomal Proximity and DNA Breaks Underlie Specific Translocations in Cancer

Lin, C.,Yang, L.,Tanasa, B.,Hutt, K.,Ju, B.g.,Ohgi, K.A.,Zhang, J.,Rose, D.W.,Fu, X.D.,Glass, C.K.,Rosenfeld, M.G. Cell Press ; MIT Press 2009 Cell Vol.139 No.6

Chromosomal translocations are a hallmark of leukemia/lymphoma and also appear in solid tumors, but the underlying mechanism remains elusive. By establishing a cellular model that mimics the relative frequency of authentic translocation events without proliferation selection, we report mechanisms of nuclear receptor-dependent tumor translocations. Intronic binding of liganded androgen receptor (AR) first juxtaposes translocation loci by triggering intra- and interchromosomal interactions. AR then promotes site-specific DNA double-stranded breaks (DSBs) at translocation loci by recruiting two types of enzymatic activities induced by genotoxic stress and liganded AR, including activation-induced cytidine deaminase and the LINE-1 repeat-encoded ORF2 endonuclease. These enzymes synergistically generate site-selective DSBs at juxtaposed translocation loci that are ligated by nonhomologous end joining pathway for specific translocations. Our data suggest that the confluence of two parallel pathways initiated by liganded nuclear receptor and genotoxic stress underlies nonrandom tumor translocations, which may function in many types of tumors and pathological processes.

China Spallation Neutron Source: Accelerator Design Iterations and R&D Status

J. Wei,C.-D. Deng,C.-H. Wang,C.-T. Shi,H. Sun,H.-F. Ouyang,H.-M. Qu,H.-Y. Dong,J. Li,J. Zhang,J.-S. Cao,J.-Y. Tang,L. Dong,L.-L. Wang,Q. Qin,Q.-B. Wang,S. Wang,S.-N. Fu,S.-X Fang,T. -G. Xu,W. Kang,Y.- 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.50 No.I

The China Spallation Neutron Source (CSNS) is a high-power, accelerator-based project currently under preparation. The accelerator complex consists of an H$^-$ ion source, an H$^-$ linac, a rapid-cycling proton synchrotron, and the transport lines. During the past year, the design of most accelerator systems went through major iterations, and initial research and developments was started on the prototyping of several key components.

A COLD NEPTUNE-MASS PLANET OGLE-2007-BLG-368Lb: Cold neptunes are common

Sumi, T.,Bennett, D. P.,Bond, I. A.,Udalski, A.,Batista, V.,Dominik, M.,Fouqué,, P.,Kubas, D.,Gould, A.,Macintosh, B.,Cook, K.,Dong, S.,Skuljan, L.,Cassan, A.,Abe, F.,Botzler, C. S.,Fukui, A.,Fu IOP Publishing 2010 The Astrophysical journal Vol.710 No.2

<P>We present the discovery of a Neptune-mass planet OGLE-2007-BLG-368Lb with a planet-star mass ratio of q = [9.5 +/- 2.1] x 10(-5) via gravitational microlensing. The planetary deviation was detected in real-time thanks to the high cadence of the Microlensing Observations in Astrophysics survey, real-time light-curve monitoring and intensive follow-up observations. A Bayesian analysis returns the stellar mass and distance at M(l) = 0.64(-0.26)(+0.21) M(circle dot) and D(l) = 5.9(-1.4)(+ 0.9) kpc, respectively, so the mass and separation of the planet are M(p) = 20(-8)(+7) M(circle plus) and a = 3.3(-0.8)(+1.4) AU, respectively. This discovery adds another cold Neptune-mass planet to the planetary sample discovered by microlensing, which now comprises four cold Neptune/super-Earths, five gas giant planets, and another sub-Saturn mass planet whose nature is unclear. The discovery of these 10 cold exoplanets by the microlensing method implies that the mass ratio function of cold exoplanets scales as dN(pl)/d log q alpha q(-0.7+/-0.2) with a 95% confidence level upper limit of n < -0.35 ( where dN(pl)/d log q alpha q(n)). As microlensing is most sensitive to planets beyond the snow-line, this implies that Neptune-mass planets are at least three times more common than Jupiters in this region at the 95% confidence level.</P>

In-situ high-energy synchrotron X-ray diffraction study of micromechanical behavior of multiple phases in Ni₄₇Ti₄₄Nb₉ shape memory alloy

Sun, G.A.,Wang, X.L.,Wang, Y.D.,Woo, W.C.,Wang, H.,Liu, X.P.,Chen, B.,Fu, Y.Q.,Sheng, L.S.,Ren, Y. Elsevier Sequoia 2013 Materials science & engineering. properties, micro Vol.560 No.-

High-energy synchrotron X-ray diffraction technique was used to in-situ characterize microstructure, lattice strain, and phase transition behavior of a Ni<SUB>47</SUB>Ti<SUB>44</SUB>Nb<SUB>9</SUB> shape memory alloy. Phase transformation kinetics and deformation mechanisms were studied under a uniaxial tension at three testing temperatures, i.e., -70<SUP>o</SUP>C, 25<SUP>o</SUP>C, and 150<SUP>o</SUP>C. At a testing temperature of -70<SUP>o</SUP>C, a complicated phase transformation with four stages of micromechanical deformation was identified which is associated with changes of martensite substructures. At room temperature of 25<SUP>o</SUP>C, there was no stress-induced selection process of variants of B19' phases observed. Whereas at a testing temperature of 150<SUP>o</SUP>C, there was no any phase transformation observed. It is verified that β-Nb phase, an effective stabilizer for the austenite, delays the process of martensitic transformation and relaxes the strain energy without strengthening the matrix. This new finding is important to understand the relationship between the micromechanical deformation behavior and phase transformations in the Ni<SUB>47</SUB>Ti<SUB>44</SUB>Nb<SUB>9</SUB> SMA.

CO2 Corrosion Mechanism of Carbon Steel in the Presence of Acetate and Acetic Acid

( D. Liu ),( C. Y. Fu ),( Z. Y. Chen ),( X. P. Guo ) 한국부식방식학회 2007 Corrosion Science and Technology Vol.6 No.5

Large-area aligned CuO nanowires arrays: Synthesis, anomalous ferromagnetic and CO gas sensing properties

C.W. Zou,J. Wang,F. Liang,W. Xie,L.X. Shao,D. J. Fu 한국물리학회 2012 Current Applied Physics Vol.12 No.5

Thermal evaporation was carried out in a horizontal quartz tube under an oxygen flow of about 50 ml/min and the influence of reaction time and temperature on the microstructure of the CuO nanowires (CNWs) is examined. The magnetic susceptibilities of the as-synthesized CNWs in the 5e300 K range were studied. It is interesting to note that the CNWs with a much larger diameter than 10 nm exhibit anomalous ferromagnetic behavior which has never been reported previously, demonstrating the effect of their peculiar morphology. The saturation magnetization (MS) and coercive field (Hc) of CNWs grown at 700 ℃ are 2.39 × 10-4 emu and 48 Oe, respectively. We fabricated gas sensors based on p-type single CNWs and demonstrate that CuO nanowires could be a promising candidate for a gas sensor with good performance. The reaction between the reducing gas and O leads to a decrease of the hole density in the surface charge layer and an increase of the CuO resistance.

Functions and values of sulfated polysaccharides from seaweed

D. P. Nagahawatta,N. M. Liyanage,Thilina U. Jayawardena,Fengqi Yang,H. H. A. C. K. Jayawardena,M. J. M. S. Kurera,Fahe Wang,Xiaoting Fu,전유진 한국조류학회I 2023 ALGAE Vol.38 No.4

Sulfated polysaccharides (SPs) isolated from seaweed have emerged as remarkable bioactive compounds with a wide spectrum of biological activities and have substantial value in the scientific and industrial domains. The current study explores the diverse biological activities of SPs and their relationship with their structures. This aids in an in-depth examination of the multifaceted biological activities of SPs, including anticoagulant, anti-inflammatory, antiviral, antioxidant, and immunomodulatory properties, which underpin their potential health benefits. Furthermore, the current study explores the complicated properties of SPs, with their extraction methodologies and techniques for precise characterization. Elucidation of the commercial significance of SPs derived from brown, red, and green seaweed by highlighting their potential applications has emphasized their importance in human well-being. Further, this review emphasizes the challenges needed to overcome research and industrial innovations for SPs. Collaboration among researchers, industry stakeholders, and regulatory authorities can overcome these challenges and elevate the potential of SPs to revolutionize industries such as pharmaceuticals, cosmeceuticals, food, and biotechnology.

DNA vaccines for cervical cancer: from bench to bedside

Chien-Fu Hung,Archana Monie,Ronald D. Alvarez,T.-C. Wu 생화학분자생물학회 2007 Experimental and molecular medicine Vol.39 No.6

ciated with human papillomaviruses (HPVs), partic-ularly HPV type 16. The clear association between HPV infection and cervical cancer indicates that HPV serves as an ideal target for development of preventive and therapeutic vaccines. Although the recently licensed preventive HPV vaccine, Gardasil, has been shown to be safe and capable of generating significant pro-tection against specific HPV types, it does not have therapeutic effect against established HPV infections teins, E6 and E7, are consistently co-expressed in HPV-expressing cervical cancers and are important in the induction and maintenance of cellular transforma-tion. Therefore, imunotherapy targeting E6 and/or E7 proteins may provide an opportunity to prevent and treat HPV-associated cervical malignancies. It has been established that T cel-mediated imunity is one of the most crucial components to defend against HPV infections and HPV-associated lesions. Therefore, ef-fective therapeutic HPV vaccines should generate ponses. DNA vaccines have emerged as an atractive approach for antigen-specific T cell-mediated im-munotherapy to combat cancers. Intradermal admin-istration of DNA vacines via a gene gun represents an efficient way to deliver DNA vaccines into professional antigen-presenting cells in vivo. Professional anti-gen-presenting cells, such as dendritic cells, are the most efective cells for priming antigen-specific T cells. Using the gene gun delivery system, we tested ing strategies for enhancing MHC class I and class II presentation of encoded model antigen HPV-16 E7. Furthermore, we have developed a strategy to prolong the life of DCs to enhance DNA vaccine potency. More recently, we have developed a strategy to generate an-tigen-specific CD4+T cell imune responses to further enhance DNA vaccine potency. The impressive pre- clinical data generated from our studies have led to several HPV DNA vaccine clinical trials.

GaN films prepared by middle frequency magnetron sputtering

M. Li,C. W. Zou,M. L. Yin,C. S. Liu,L. P. Guo,D. J. Fu 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.-

A middle-frequency (MF) sputter system was developed for the growth of GaN films. The key part of the system is dish-shape twin targets back cooled by refrigerated water and powered by a 40-kHz MF power supply. GaN films prepared on Si(111) by this system were hexagonal in structure. The X-ray diffraction pattern shows (002) as the preference orientation. GaN films produced under optimal conditions have an almost 1:1 N:Ga ratio as determined by energy-dispersive spectroscopy. We obtained a band gap of 3.2 eV by extrapolating absorption plots for GaN films deposited on glass substrate under standard conditions. A middle-frequency (MF) sputter system was developed for the growth of GaN films. The key part of the system is dish-shape twin targets back cooled by refrigerated water and powered by a 40-kHz MF power supply. GaN films prepared on Si(111) by this system were hexagonal in structure. The X-ray diffraction pattern shows (002) as the preference orientation. GaN films produced under optimal conditions have an almost 1:1 N:Ga ratio as determined by energy-dispersive spectroscopy. We obtained a band gap of 3.2 eV by extrapolating absorption plots for GaN films deposited on glass substrate under standard conditions.