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Zhang CC, Zhang ZM, Dai RC, Wang ZP, Ding ZJ. High pressure luminescence and Raman studies on the phase transition of Gd2O3:Eu3+ nanorods. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2011; 11:9887-9891. [PMID: 22413315 DOI: 10.1166/jnn.2011.5228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The cubic Gd2O3:Eu3+ nanorods were synthesized by a hydrothermal method. The SEM image indicated the nanorods with diameter of 30-35 nm and length of 200-500 nm. The structural stability of Gd2O3:Eu3+ nanorods was investigated by in situ high pressure luminescence and Raman spectra up to 18.9 GPa at room temperature. The results reveals a pressure-induced phase transition from cubic to hexagonal structure at about 11.3 GPa. After releasing pressure, the part of hexagonal structure is retained and the other transfers to monoclinic phase.
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Wang LP, Zhang ZM. Phonon-mediated magnetic polaritons
in the infrared region. OPTICS EXPRESS 2011; 19 Suppl 2:A126-35. [PMID: 21445214 DOI: 10.1364/oe.19.00a126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Magnetic polaritons that couple electromagnetic waves with magnetic excitation can be used for tailoring the radiative properties of materials in energy-harvesting and other applications. Previous studies used metallic microstructures to induce magnetic responses. With rigorous coupled-wave analysis (RCWA), transmission enhancement with a SiC slit array and coherent thermal emission with a SiC deep grating is theoretically demonstrated in the infrared within the phonon absorption band. The field distributions and the agreement in the resonance frequencies predicted from both RCWA and LC circuit models strongly suggest that magnetic polaritons exist in the SiC microstructures. This type of magnetic polariton is mediated by vibration of atoms in polar materials (i.e., optical phonons), rather than by free electrons in metals. Our results suggest that phonon-mediated magnetic polaritons have promising applications such as filters and selective coherent emitters in the infrared spectral region.
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Zhu XS, Zhang ZM, Mao HQ, Geng DC, Zou J, Wang GL, Zhang ZG, Wang JH, Chen L, Yang HL. A novel sheep vertebral bone defect model for injectable bioactive vertebral augmentation materials. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:159-164. [PMID: 21127948 DOI: 10.1007/s10856-010-4191-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 11/19/2010] [Indexed: 05/30/2023]
Abstract
New injectable bone substitutes have been developed that are, unlike polymethylmethacrylate, biologically active and have an osteogenic effect leading to osteogenesis and bone remodeling for vertebroplasty or kyphoplasty. In this study, we developed a sheep vertebral bone defect model to evaluate the new bioactive materials and assessed the feasibility of the model in vivo. Bone voids were experimentally created on lumbar vertebrae L2-L5 with L1 and L6 left intact as a normal control in mature sheep. The defect vertebrae L2-L5 in each sheep were randomized to receive augmentation with calcium phosphate cement (CPC) or sham. Vertebrae (L1-L6) were collected after 2 and 24 weeks of the cement augmentation and their strength and stiffness, as well as osseointegration activity and biodegradability, were evaluated. Finally, CPC significantly improved the strength and stiffness of vertebrae but did not yet restore it to the normal level at 24 weeks. Osteogenesis occurred at a substantially high level after 24 weeks of CPC augmentation or sham. Therefore, the sheep vertebral model with one void, 6.0 mm in diameter and 15.0 mm in depth, is replicable and can be used for evaluating the new injectable bioactive materials in vertebral augmentation or reconstruction.
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Huang Q, Gao SB, Zhang ZM, Lin HJ, Pan GT, Yang KC, Rong TZ. Construction of root library by SSH and preliminary analysis of genes responsible for phosphorus deficiency in maize. GENETIKA 2010; 46:1619-1625. [PMID: 21428250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An elite maize inbred line with high tolerance to low phosphorus, 178, was studied for constructing root library and analyzing some genes closely related to phosphorus (P) deficiency using SSH and Semi-quantitative RT-PCR. As a result, 3648 preliminary clones were obtained for root library under stress of P deficiency. By DNA sequencing of 34 random clones, we obtained 23 unique EST sequences which are involved in functions of root cell structure, tolerance and defense, protein modification and composition, transcription regulation, metabolism, and other unknown aspects. Five representative genes were further analyzed for their expression models. The results suggested that the molecular mechanism to adapt P deficiency in maize, performed by multi-genes with different contributions, is similar to rice, Arabidopsis and soybean. The expression order of 5 low P tolerant genes in maize root was PAP, GCS, TOM, PDI and AIP. And it was considered preliminarily that physiological and biochemical changes were prior to morphologic changes in maize root and the essential tolerance to low P may be determined by extending absorption of P to wide soil range through adaption of root architecture and root secretions, which is the greatest difference between tolerant and sensitive maize varieties under low P stress.
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Dai RC, Zhang ZM, Zhang CC, Ding ZJ. Photoluminescence and raman studies of Y2O3:Eu(3+) nanotubes under high pressure. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:7629-7633. [PMID: 21137998 DOI: 10.1166/jnn.2010.2752] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this work, the cubic compound Y2O3:Eu(3+) nanotubes with diameter of 70-90 nm and length of 2-3 microm are synthesized by a hydrothermal method. Photoluminescence and Raman spectra of Y2O3:Eu(3+) nanotubes in a diamond anvil cell under high pressure are measured at room temperature. The 5D0 --> 7F(0,1,2) transitions of the Eu(3+) ions exhibit red shifts to higher wavelength with pressure increasing. Above 13.4 GPa, all the Raman active modes disappear. When the pressure is released from 25.6 GPa to ambient pressure, these Raman peaks are not retrieved; this fact indicates that the nanotubes are transformed into amorphous from cubic phase at about 13.4 GPa. It may be related to the collapse of nanotube form under high pressure condition.
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Mei HP, Zhang ZM, Ding ZJ. Monte Carlo simulation of X-ray photoemission electron microscopic image for Ag/Si nano-structure. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:7824-7828. [PMID: 21138042 DOI: 10.1166/jnn.2010.2925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
With the development of the third generation synchrotron radiation sources the X-ray photoemission electron microscopy (XPEEM) is playing as a powerful tool for analyzing specimens with spatial resolution about tens of nanometer. It has been used to observe the chemical reaction process, and to investigate the surfaces, interfaces, thin films, buried layers and nano-structures. XPEEM image signals are contributed from photoelectrons, Auger electrons, backscattering electrons and secondary electrons excited by X-rays of certain energy. In this work, a Monte Carlo model for XPEEM image simulation is built. XPEEM images in total electron yield (TEY) mode are simulated with this model for several nanostructures (spheres and cylinders) of silver deposited on/in a silicon substrate (Ag/Si). The simulated XPEEM image in TEY mode for Ag dot array on a Si substrate is quite close to an experimental image. Furthermore, the XPEEM image simulation has been performed for different incident X-rays and for different geometric structures.
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Wang XJ, Flicker JD, Lee BJ, Ready WJ, Zhang ZM. Visible and near-infrared radiative properties of vertically aligned multi-walled carbon nanotubes. NANOTECHNOLOGY 2009; 20:215704. [PMID: 19423943 DOI: 10.1088/0957-4484/20/21/215704] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This work investigates the reflection and scattering from vertically aligned carbon nanotubes, fabricated on silicon substrate using thermally enhanced chemical vapor deposition with both tip-growth and base-growth mechanisms. The directional-hemispherical reflectance in the visible and near-infrared wavelengths was measured with an integrating sphere. The polarization-dependent bidirectional reflectance distribution function was characterized with a laser scatterometer at the wavelength of 635 nm. The effective medium theory was used to elucidate the mechanism of high absorptance (greater than 0.97 in the spectral region from 400 to 1800 nm) of the multi-walled carbon nanotube samples. It is observed that scattering by impurities on the top of the nanotubes, by the nanotube tips, and by defects and misalignment can significantly increase the reflectance and introduce retroreflection. This study may facilitate application of carbon nanotubes in pyroelectric detectors as well as thermophotovoltaic emitters and absorbers.
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Pan Q, Xu WJ, Tang YQ, Yang Y, Ma J, Zhang ZM, Liu Y, Zhou QS, Peng LY, Li PJ, Liang DD, Chen HZ, Li J, Xiao JJ, Zhang J, Chen YH. Unique histological features of the left atrial posterior wall. J Int Med Res 2009; 37:392-9. [PMID: 19383233 DOI: 10.1177/147323000903700214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The left atrial posterior wall (LAPW) plays a critical role in atrial fibrillation, but the underlying mechanism remains unclear. In the present study, we sought to characterize the histological features of the LAPW. Different atrial regions were dissected from hearts of normal Sprague-Dawley rats and humans. Haematoxylin/eosin and van Gieson staining were used to analyse atrial cardiomyocyte arrangement and collagen distribution, respectively. Intercellular junctions were evaluated by transmission electron microscopy. In contrast with other atrial regions, the LAPW exhibited more disorganized cardiomyocytes, larger intercellular spaces and variable myocardial fibre arrangement. The proportion of collagen was significantly higher in the LAPW than in other atrial regions. Interestingly, desmosomes were sparse along with intercellular gaps in the LAPW. In summary, distinct disarrangement of cardiomyocytes and an abundance of collagen exist in the LAPW. The sparsity of desmosomes in the LAPW may be related to the heterogeneous distribution and separation of atrial myocytes.
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Shen B, Sun FH, Zhang ZM. Experimental and molecular dynamics investigation on tribological properties of nanocrystalline diamond films. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:788-792. [PMID: 19441393 DOI: 10.1166/jnn.2009.c025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Nanocrystalline diamond films were deposited on cemented tungsten carbide substrates using hot filament chemical vapor deposition (HFCVD) method, and their tribological properties were investigated by friction experiments and classical molecular dynamics simulations. The friction tests were performed on a ball-on-plate type reciprocating friction tester under various normal loads and sliding velocities conditions; the experimental results suggested that the friction coefficient of diamond films showed increasing tendency with the growing normal load and sliding velocity. Furthermore, classical molecular dynamics simulations were conducted to investigate the changes in atomic scale friction behaviors of diamond films under extremely high normal load and sliding velocity conditions, the atomistic sliding mechanism was also discussed in this study.
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Xiao SM, Zhang ZM, Li HM, Ding ZJ. Monte Carlo simulation of scanning electron microscope image of sidewall shape for linewidth measurement. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1655-1658. [PMID: 19441593 DOI: 10.1166/jnn.2009.c225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Scanning electron microscope (SEM) has been an important tool for the observation of surface micro-structures of various kinds of materials. The secondary electron image, which uses secondary electrons that escaped from the surface under a primary electron beam bombardment as imaging signals, can provide the surface topographic information with a resolution up to sub-nm with a modern SEM. Therefore, it can be used for nanometrology with improved measurement accuracy by critical dimension scanning electron microscope (CD-SEM). This work aims to develop a Monte Carlo simulation method for application to the nanometer linewidth measurement for semiconductor devices by SEM. The simulation will provide a theoretical analysis of the influence of various parameters of specimen and electron beam on the estimation of linewidth and the sidewall angles. The result will be helpful for the improvement of the measurement precision by CD-SEM.
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Peng HF, Zhang ZF, Wu B, Chen XH, Zhang GQ, Zhang ZM, Wan BH, Lu YP. Molecular mapping of two reverse photoperiod-sensitive genic male sterility genes (rpms1 and rpms2) in rice (Oryza sativa L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2008; 118:77-83. [PMID: 18810384 DOI: 10.1007/s00122-008-0877-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Accepted: 08/23/2008] [Indexed: 05/26/2023]
Abstract
The reverse photoperiod-sensitive genic male sterility (PGMS) and thermo-sensitive genic male sterility (TGMS) lines have an opposite phenotype compared with normal PGMS and TGMS lines widely used by the two-line system in current hybrid rice seed production. Thus, the application of reverse PGMS and TGMS lines can compensate PGMS and TGMS lines in hybrid rice production. YiD1S is a reverse PGMS line, in which pollen fertility is mainly regulated by day-length, but also influenced by temperature. Genetic analysis indicated that male sterility of YiD1S was controlled by two recessive major genes. An F(2) population from a cross between YiD1S and 8528 was developed and used for molecular mapping of the two reverse PGMS genes which were first named rpms1 and rpms2. Both simple sequence repeat (SSR) markers and bulked segregant analysis (BSA) were used in this study. As a result, one reverse PGMS gene (rpms1) was mapped to the interval between SSR markers RM22980 (0.9 cM) and RM23017 (1.8 cM) on chromosome 8. Eight SSR markers, YDS818, RM22984, RM22986, RM22997, YDS816, RM23002, RM339 and YDS810 completely co-segregated with the rpms1 gene. Another reverse PGMS gene (rpms2) was mapped to the interval between SSR markers RM23898 (0.9 cM) and YDS926 (0.9 cM) on chromosome 9. The physical mapping information from publicly available resources shows that the rpms1 and rpms2 loci are located in a region of 998 and 68 kb, respectively. The analysis based on marker genotypes showed that the effect of rpms1 was slightly larger than that of rpms2 and that the two genes interacted in controlling male sterility.
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Lee BJ, Wang LP, Zhang ZM. Coherent thermal emission by excitation of magnetic polaritons between periodic strips and a metallic film. OPTICS EXPRESS 2008; 16:11328-11336. [PMID: 18648451 DOI: 10.1364/oe.16.011328] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 07/10/2008] [Indexed: 05/26/2023]
Abstract
The present paper theoretically demonstrates coherent thermal emission in the infrared region by exciting magnetic polaritons between metallic gratings and an opaque metallic film, separated by a dielectric spacer. The coupling of the metallic strips and the film induces a magnetic response that is characterized by a negative permeability and positive permittivity. On the other hand, the metallic film intrinsically exhibits a negative permittivity and positive permeability in the near infrared. This artificial structure is equivalent to a pair of single-negative materials. By exciting surface magnetic polaritons, large emissivity peaks can be achieved at the resonance frequencies and are almost independent of the emission angle. The resonance frequency of the magnetic response can be predicted by an analogy to an inductor and capacitor circuit. The proposed structure can be easily constructed using micro/nanofabrication.
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63
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Zhao HW, Sun LT, Zhang XZ, Guo XH, Cao Y, Lu W, Zhang ZM, Yuan P, Song MT, Zhao HY, Jin T, Shang Y, Zhan WL, Wei BW, Xie DZ. Intense beam production of highly charged heavy ions by the superconducting electron cyclotron resonance ion source SECRAL. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:02A315. [PMID: 18315105 DOI: 10.1063/1.2804900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
There has been increasing demand to provide higher beam intensity and high enough beam energy for heavy ion accelerator and some other applications, which has driven electron cyclotron resonance (ECR) ion source to produce higher charge state ions with higher beam intensity. One of development trends for highly charged ECR ion source is to build new generation ECR sources by utilization of superconducting magnet technology. SECRAL (superconducting ECR ion source with advanced design in Lanzhou) was successfully built to produce intense beams of highly charged ion for Heavy Ion Research Facility in Lanzhou (HIRFL). The ion source has been optimized to be operated at 28 GHz for its maximum performance. The superconducting magnet confinement configuration of the ion source consists of three axial solenoid coils and six sextupole coils with a cold iron structure as field booster and clamping. An innovative design of SECRAL is that the three axial solenoid coils are located inside of the sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. During the commissioning phase at 18 GHz with a stainless steel chamber, tests with various gases and some metals have been conducted with microwave power less than 3.5 kW by two 18 GHz rf generators. It demonstrates the performance is very promising. Some record ion beam intensities have been produced, for instance, 810 e microA of O(7+), 505 e microA of Xe(20+), 306 e microA of Xe(27+), and so on. The effect of the magnetic field configuration on the ion source performance has been studied experimentally. SECRAL has been put into operation to provide highly charged ion beams for HIRFL facility since May 2007.
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Lee BJ, Chen YB, Zhang ZM. Surface waves between metallic films and truncated photonic crystals observed with reflectance spectroscopy. OPTICS LETTERS 2008; 33:204-206. [PMID: 18246129 DOI: 10.1364/ol.33.000204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have analyzed and demonstrated surface-wave excitations, by propagating waves in air, at the interface between a truncated photonic crystal (PC) and a silver film in the near-infrared. The truncated PC was fabricated with several unit cells of alternating SiO(2) and Si(3)N(4) layers. The dispersion relation of surface waves was calculated using the supercell method. A Fourier-transform infrared spectrometer measured the spectral reflectance of the fabricated sample at different incidence angles. An angle-resolved laser scatterometer measured the reflectance as a function of the incidence angle at the wavelength of 891 nm. The agreement between the resonance conditions obtained from experiments and the calculated dispersion relation manifests that surface waves at the PC-Ag interface may be utilized to build coherent thermal-emission sources.
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Sun LT, Shang Y, Ma BH, Zhang XZ, Feng YC, Li XX, Wang H, Guo XH, Song MT, Zhao HY, Zhang ZM, Zhao HW, Xie DZ. An electron cyclotron resonance ion source based low energy ion beam platform. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:02B711. [PMID: 18315202 DOI: 10.1063/1.2821504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
To satisfy the requirements of surface and atomic physics study in the field of low energy multiple charge state ion incident experiments, a low energy (10 eV/q-20 keV/q) ion beam platform is under design at IMP. A simple test bench has been set up to test the ion beam deceleration systems. Considering virtues such as structure simplicity, easy handling, compactness, cost saving, etc., an all-permanent magnet ECRIS LAPECR1 [Lanzhou all-permanent magnet electron cyclotron resonance (ECR) ion source No. 1] working at 14.5 GHz has been adopted to produce intense medium and low charge state ion beams. LAPECR1 source has already been ignited. Some intense low charge state ion beams have been produced on it, but the first test also reveals that many problems are existing on the ion beam transmission line. The ion beam transmission mismatches result in the depressed performance of LAPECR1, which will be discussed in this paper. To obtain ultralow energy ion beam, after being analyzed by a double-focusing analyzer magnet, the selected ion beam will be further decelerated by two afocal deceleration lens systems, which is still under design. This design has taken into consideration both ions slowing down and also ion beam focusing. In this paper, the conceptual design of deceleration system will be discussed.
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Xia YL, Ding J, Zhang ZM, Rong TZ, Shi LY, Pan GT. Isolation of EF1gamma from calli regenerating SSH library in Maize (Zea mays). GENETIKA 2007; 43:1647-1650. [PMID: 18592691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
18599Hong, a good Maize (Zea mays) inbred line as well as good transformation acceptor with high regeneration capacity, was used for isolating embryonic callus regeneration genes. Subtractive library was constructed by Suppression subtractive hybridization and screened by Reverse Northern Hybridization. The clones of No. 27 was randomly picked to sequence. NCBI blastx results showed the similarity to elongation factor 1gamma in rice.
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Li YY, Wang R, Zhang GL, Zheng YJ, Zhu P, Zhang ZM, Fang XX, Feng Y. An archaeal histone-like protein mediates efficient p53 gene transfer and facilitates its anti-cancer effect in vitro and in vivo. Cancer Gene Ther 2007; 14:968-75. [PMID: 17853924 DOI: 10.1038/sj.cgt.7701086] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The improvement of the transfection efficiency of the non-viral-based gene delivery systems is a key issue for the application in gene therapy. We have previously described an archaeal histone-like protein-based (HPhA) gene delivery system and showed that HPhA formed stable non-covalent complexes with nucleic acids and improved their delivery by using beta-galactosidase as a reporter gene. In this study, the wild-type p53 gene was transfected into the cancer cells using the HPhA as a vector, and the expression level and the activity of p53 gene were evaluated both in vitro and in vivo. Gene expression was determined by real-time reverse transcriptase-PCR and western blotting analysis. The cellular growth inhibition and apoptosis of HPhA-mediated p53 transfection were assessed by XTT (sodium 3'-[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro)benzene sulfonic acid hydrate) assay and annexin V-FITC (fluorescein isothiocyanate) staining, respectively. Further more, transfection of HPhA/p53 into CNE (nasopharyngeal carcinoma cell line)-xenografted nude mice was performed and tumor growth was measured. The present study demonstrates that HPhA enhances the efficiency of p53 gene transfer and antitumor activity compared with the widely used Lipofectamine. These results demonstrate that HPhA enhances the in vitro and in vivo efficiency of p53 gene transfer and suggest that it may be served as a promising tool for gene delivery and gene therapy.
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Sun LT, Zhao HW, Zhang ZM, Wang H, Ma BH, Zhang XZ, Li XX, Feng YC, Li JY, Guo XH, Shang Y, Zhao HY. 36-segmented high magnetic field hexapole magnets for electron cyclotron resonance ion source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:053302. [PMID: 17552813 DOI: 10.1063/1.2740147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Two high magnetic field hexapoles for electron cyclotron resonance ion source (ECRIS) have successfully fabricated to provide sufficient radial magnetic confinement to the ECR plasma. The highest magnetic field at the inner pole tip of one of the magnets exceeds 1.5 T, with the inner diameter (i.d.)=74 mm. The other hexapole magnet provides more than 1.35 T magnetic field at the inner pole tip, and the i.d. is 84 mm. In this article, we discuss the necessity to have a good radial magnetic field confinement and the importance of a Halbach hexapole to a high performance ECRIS. The way to design a high magnetic field Halbach structure hexapole and one possible solution to the self-demagnetization problem are both discussed. Based on the above discussions, two high magnetic field hexapoles have been fabricated to be utilized on two high performance ECRISs in Lanzhou. The preliminary results obtained from the two ECR ion sources are given.
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Zhang ZM, Zhao MJ, Ding HP, Rong TZ, Pan GT. QTL mapping analysis of plant height and ear height of maize (Zea mays L.). GENETIKA 2006; 42:391-6. [PMID: 16649666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Genetic map containing 103 microsatellite loci obtained on 200 F2 plants derived from the cross R15 x 478 was used for quantitative trait loci (QTL) mapping in maize. QTL were characterized in a population of 200 F2:4 lines, derived from selfing the F2 plants, and were evaluated with two replications in two environments. QTL determinations were made from the mean of these two environments. Plant height (PH) and ear height (EH) were measured. Using composite interval mapping (CIM) method, a total of 14 distinct QTLs were identified: nine for PH and five for EH. Additive, partial dominance, dominance, and overdominance actions existed among all detected QTL affecting plant height and ear height. The QTL explained 78.27% of the phenotypic variance of PH and 41.50% of EH. The 14 QTLs displayed mostly dominance or partial dominance gene action and mapped to chromosomes 2, 3, 4, 8 and 9.
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Fu CJ, Zhang ZM, Tanner DB. Planar heterogeneous structures for coherent emission of radiation. OPTICS LETTERS 2005; 30:1873-5. [PMID: 16092374 DOI: 10.1364/ol.30.001873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The coupling of excited surface polaritons with thermal radiation through diffraction by gratings results in coherent thermal emission in a certain frequency range toward well-defined directions for p polarization. A planar coherent source is proposed that uses multilayers of negative permittivity (epsilon) and negative permeability (mu) materials. Owing to the excitation of surface polaritons at the interface between the negative-epsilon and negative-mu layers, coherent emission can be achieved for both s and p polarization. Moreover, one can control the emission frequency and direction by adjusting the layer thicknesses.
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Lougovski P, Solano E, Zhang ZM, Walther H, Mack H, Schleich WP. Fresnel representation of the Wigner function: an operational approach. PHYSICAL REVIEW LETTERS 2003; 91:010401. [PMID: 12906520 DOI: 10.1103/physrevlett.91.010401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2002] [Revised: 04/16/2003] [Indexed: 05/24/2023]
Abstract
We present an operational definition of the Wigner function. Our method relies on the Fresnel transform of measured Rabi oscillations and applies to motional states of trapped atoms as well as to field states in cavities. We illustrate this technique using data from recent experiments in ion traps [Phys. Rev. Lett. 76, 1796 (1996)]] and in cavity QED [Nature (London) 403, 743 (2000)]]. The values of the Wigner functions of the underlying states at the origin of phase space are W(|0>)(0)=+1.75 for the vibrational ground state and W(|1>)(0)=-1.4 for the one-photon number state. We generalize this method to wave packets in arbitrary potentials.
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Liang SC, Wang H, Zhang ZM, Zhou YY, Zhang HS. Spectrofluorimetric determination of thiols by use of N[P-(2-benzoxazolyl)phenyl]maleimide. FRESENIUS' JOURNAL OF ANALYTICAL CHEMISTRY 2001; 370:1117-9. [PMID: 11583099 DOI: 10.1007/s002160100777] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The weak fluorescence of N-[P-(2-benzoxazolyl)phenyl]maleimide (BOPM) can be greatly enhanced by thiol-containing compounds. A sensitive and simple spectrofluorimetric method based on the use of BOPM has been developed for the determination of thiols such as cysteine (Cys) and reduced glutathione (GSH). Calibration plots were linear in the concentration range from 0 to 1.6 x 10(-7) mol L(-1) for Cys and 0 to 1.7 x 10(-7) mol L(-1) for GSH. The detection limits (3a) were 2.36 x 10(-10) mol L(-1) for Cys and 1.49 x 10(-10) mol L(-1) for GSH. Many other amino acids (present at 100-fold greater concentrations) did not interfere with the determination. The proposed method has been used for the determination of Cys in protein hydrolysate and cystine electrolyte or GSH in serum, with recoveries of 95.4-103.7%.
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73
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Rautaharju PM, Nelson JC, Kronmal RA, Zhang ZM, Robbins J, Gottdiener JS, Furberg CD, Manolio T, Fried L. Usefulness of T-axis deviation as an independent risk indicator for incident cardiac events in older men and women free from coronary heart disease (the Cardiovascular Health Study). Am J Cardiol 2001; 88:118-23. [PMID: 11448406 DOI: 10.1016/s0002-9149(01)01604-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
T-axis shift has been reported to be an indicator of increased mortality risk. We evaluated the association of spatial T-axis deviation with incident coronary heart disease (CHD) events in older men and women free from clinically overt CHD. Spatial T-axis deviation was measured from the standard 12-lead electrocardiogram of a subgroup of 4,173 subjects considered free of CHD at baseline in the Cardiovascular Health Study, a prospective cohort study of risk factors for CHD and stroke in older men and women. Cox regression analysis was used to evaluate the association of altered repolarization with the risk of incident CHD events. The prevalence of marked T-axis deviation (> or =45 degrees ) was 12%. During the median follow-up of 7.4 years, there were 161 CHD deaths, 743 deaths from all causes, and 679 incident CHD events. Adjusting for demographic and clinical risk factors, including other electrocardiographic abnormalities, there was a nearly twofold excess risk of CHD death, and approximately a 50% excess risk of incident CHD and all-cause mortality for those with marked T-axis deviation. From other electrocardiographic abnormalities, only QT prolongation was associated with excess risk for incident CHD comparable to that for abnormal T-axis deviation. These results suggest that T-axis deviation is an easily quantified marker for subclinical disease and an independent indicator for the risk of incident CHD events in older men and women free of CHD.
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Zielenska M, Zhang ZM, Ng K, Marrano P, Bayani J, Ramirez OC, Sorensen P, Thorner P, Greenberg M, Squire JA. Acquisition of secondary structural chromosomal changes in pediatric ewing sarcoma is a probable prognostic factor for tumor response and clinical outcome. Cancer 2001; 91:2156-64. [PMID: 11391597 DOI: 10.1002/1097-0142(20010601)91:11<2156::aid-cncr1244>3.0.co;2-i] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The Ewing sarcoma (ES) group of tumors commonly have the t(11;22)(q24;q12) or other rearrangements involving 22q12. In addition to these consistent aberrations, both numeric and structural aberrations have been reported: namely gains of chromosomes 8 and 12, the unbalanced translocation t(1;16), and deletions at the short arm of chromosome 1. METHODS To evaluate the frequency and to study the prognostic implications of some of these aberrations in children, the authors performed a pilot study of 26 ES pediatric patients by classic cytogenetics and/or interphase fluorescence in situ hybridization (FISH) and compared these data with clinical parameters. RESULTS Gains of chromosomes 8 and 12 were detected, by interphase FISH, in 48% (10 of 21) and 38% (6 of 16) of the tumors, respectively, and this was not significant with respect to treatment response. Statistical analysis revealed that the presence of additional secondary structural chromosomal aberrations was associated with an unfavorable outcome (P = 0.0034 as an independent prognostic value as an unfavorable marker). Presence of metastasis at diagnosis also was found to be associated with poor outcome (P = 0.0131). Spectral karyotyping analysis was shown to facilitate the detection of more complex structural chromosomal aberrations in a representative ES tumor. CONCLUSIONS It is important to determine whether additional structural chromosomal aberrations are present in ES tumors because it appears that a more complex karyotype with multiple chromosomal aberrations is associated with poor outcome in ES.
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MESH Headings
- Adolescent
- Bone Neoplasms/genetics
- Bone Neoplasms/pathology
- Child
- Child, Preschool
- Chromosome Aberrations/genetics
- Chromosomes, Human, Pair 1/genetics
- Chromosomes, Human, Pair 12/genetics
- Chromosomes, Human, Pair 8/genetics
- Female
- Follow-Up Studies
- Humans
- In Situ Hybridization, Fluorescence
- Infant
- Karyotyping
- Male
- Prognosis
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/pathology
- Survival Analysis
- Treatment Outcome
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Zhang ZM, Yang SL. [Change of Fo and vocal range of pathological voice]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2000; 14:260-1. [PMID: 12541533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the relationship between Fo and true or falsetto range in four phonation modes. METHOD Testing Fo of lowest true voice, comfortable voice, highest true voice and falsetto voice. RESULT In pathological voice, Fo of lowest true voice increases, Fo of highest falsetto voice reduces, true and falsetto voice range become thin and the change of falsetto voice range is more obvious. CONCLUSION Fo of falsetto highest voice reduces, falsetto voice rang become thin in pathological voice.
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