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An efficient radial-polarization Yb-fiber laser with an intracavity Brewster axicon is demonstrated. The fraction of ASE at low pumping and parasitical oscillation are minimized by adopting bidirectional pumping and angle-polished fiber end. So far, except for the improvement in polarization purity and cylindrical symmetry of output beam, 39-mW output power is obtained at 460-mW launched pump power with 13.8% slope efficiency. And also a new type of low-V-parameter multi-mode gain fiber with doughnut concentration distribution of active ions in fiber core profile is predicted to be promising in improving the laser performance further.

The photoluminescence spectra of titanium dioxide (TiO2) nanocrystals doped with Eu3+ (molar ratio Eu3+/TiO2 = 0, 1, 2, 4%) are investigated under different excitation wavelengths. An ultraviolet band of emission energy higher than the energy gap is found for excitation wavelengths larger than 315 nm when the Eu3+ content is higher than 2%. The new emission band redshifts and its emission intensity is intensified with the increase of excitation wavelength. The emission mechanism for the new ultraviolet emission band is analyzed.

The recently developed SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) ion source is a high-performance next- generation ECR ion source. It is designed to produce high current, high charge state heavy ion beams for HIRFL (Heavy Ion Research Facility in Lanzhou) cyclotrons. In August 2005, the first plasma was obtained at 18 GHz. Preliminary performances of SECRAL on gaseous elements such as oxygen, argon and xenon are quite promising, with many world record ion beams being delivered such as 2.3 emA O 6+ , 0.81 emA O 7+ , 0.81 emA Ar 11+ , 0.5 emA Xe 20+ , 306 eμA Xe 27+ and 9 eμA Xe

The sample of Eu 3+ -doped TiO 2 (Eu 3+ /TiO 2 ) nanocrystals is synthesized by the sol–gel method with hydrothermal treatment. Raman and photoluminescence (PL) spectra of the sample have been investigated under high pressure up to 18 GPa using a diamond anvil cell. At ambient pressure, a strong PL signal associated with the 5 D 0 → 7 F J (J=0,1,2,3,4) transition of Eu 3+ under the excitation wavelength at 514.5 nm is observed. The emission peaks red shift slightly and the intensity decreases with the increase of pressure, while the intensity ratio between 5 D 0 → 7 F 2 and 5 D 0 → 7 F 1 decreases dramatically. A phase transition is observed at 8.2–10.6 GPa by the Raman spectra analysis. Reducing of the intensity ratio between 5 D 0 → 7 F 2 and 5 D 0 → 7 F 1 value indicates the rising of the site symmetry and the weakening of the covalency of Eu–O bond.

Pressure-induced changes on fluorescence spectra of Congo red molecules were examined up to 8.7 GPa using a diamond anvil cell at room temperature. The spectra changes are demonstrated to be sensitive to the pressure and solvent conditions. At hydrostatic pressure and with a solvent used as a pressure transmitting medium the fluorescence spectra show increase of intensity with elevated pressure up to about 2.3 GPa and then drop at higher pressures. For Congo red crystal under quasi-hydrostatic condition without solvent the fluorescence intensity decreases monotonically and the lower energy band becomes dominant with the pressure increasing. The three vibronic bands show red shifts with increase of pressure.

Pressure-induced changes of the fluorescence spectra of Nd:YVO 4 crystals have been studied up to 10.88 GPa using a diamond anvil cell at ambient temperature. The changes of spectra indicate that pressure has remarkably influenced both the fluorescence intensity and the energy levels of Nd:YVO 4 crystals. With pressure increasing up to 7.45 GPa, the intensity of the spectra decreases and the peak positions shift red gradually. For pressure above 7.5 GPa, the fluorescence intensity decreases quickly and the shift rates of the peaks is slowed down. This suggests that 7.5 GPa is a critical point of the pressure at which the crystal may have a pressure-induced phase transition and the crystal-field changes. The new characters of the fluorescence spectra remain stable as the pressure is released to ambient pressure.

Based on the introduction of the construction and basic principle of the airborne optoelectronic pod, in accordance with the performance standards of the pod, the total solution scheme of the automatic test system used for testing the combination property is proposed in this paper. The main structure, hardware and software design of the system based on the virtual instruments technology are also discussed in detail. The result of the true run proves the practicality, efficiency, high accuracy and other characteristics of the computer aided testing system based on virtual instruments.

A brief overview is given on several aspects of applications of the Monte Carlo (MC) simulation method to surface-related electron spectroscopy and microscopy. For the MC modeling of electron interaction with solids, the electron inelastic scattering cross section is calculated by the use of bulk dielectric function with optical constants in a dielectric functional approach. This has enabled the systematic reproductions of the experimental energy distributions of backscattered electrons for a number of elemental materials. An improved calculation of backscattering factor for quantitative AES analysis has been performed on the basis of a new definition and by making use of the up-to-date relevant cross sections. The physical reason is given for the backscattering factor that can be less than unity for very low primary energies close to the ionization energy and/or for large incident angles. For the MC modeling of electron interaction with surfaces, the inelastic scattering of electrons moving in a surface region is treated in a self-energy formalism. The model has enabled the evaluation of the surface excitation effect through the calculation of position-dependent electron IMFP. A simulation of REELS spectra for Ag is compared with an experiment; a reasonable agreement found on the surface plasmon peak intensity normalized with elastic peak intensity thus verifies this modeling of electron interaction with surfaces. Finally, the MC simulation code has been extended to deal with complex sample geometries. By using basic building blocks to construct a complex geometry and the ray-tracing technique for correction of electron flight-step-length sampling, the structured and/or inhomogeneous sample can be modeled with reasonable flexibility. Copyright © 2006 John Wiley & Sons, Ltd.

The electron inelastic scattering in silver is studied both experimentally and theoretically. The reflection electron energy loss spectroscopy (REELS) spectra were measured using the ESA-31. It is shown that the surface excitation is enhanced with decreasing primary energy. For the higher resolution spectra with the narrower energy distribution of elastically scattered electrons, the Tougaard’s recursive formula describes inelastic scattering cross section from the measured energy loss spectrum as well as the extended Landau approach. At low primary energies, the differential inverse inelastic mean free path (DIIMFP) for low loss energies extracted by Tougaard’s recursive method is smaller than that by the extended Landau approach. The latter method is better for measured REELS spectra with a large full width at half maximum (FWHM) of elastic peak (e.g. for a CMA). The effective energy loss function (EELF) has been derived from these experiments based on the extended Landau approach. The Monte Carlo simulated REELS spectra with the derived EELF agree well with the experimental spectra. Copyright  2006 John Wiley & Sons, Ltd.

The contribution to total electron yield (TEY) from all emitted electrons consisting of photoelectrons, Auger electrons, their inelastic-scattering background and secondary electrons that are excited by X rays with energies near the Ag L3 edge was calculated by a Monte Carlo simulation method that describes electron scattering processes in solids as well as the secondary electron cascade production. The simulated TEYs at different energies are very close to the experimental values, and the ratio of TEYs at the X-ray energies of 3370 and 3340 eV also agrees with the measured one. The secondary electrons contribute ∼65% to all emitted electrons; while ∼30% is due to the widely distributed energy-loss background for inelastic scattered electrons. X-ray absorption near-edge structure (XANES) spectrum in TEYs simulated on the basis of a Monte Carlo method reproduces the measured spectrum with considerable success. Copyright © 2006 John Wiley & Sons, Ltd.

The no-loss peak of Ag 3d photoelectrons and 3d XPS spectra at different incidence angles of X-rays were measured with a double angular photoelectron intelligent analyzers (DAPHNIA) attached to a wide energy range X-ray beam line BL15XU at SPring-8. Ag 3d X-ray photoelectron spectroscopy (XPS) spectra were simulated by a Monte Carlo (MC) method using an effective energy loss function. Confirming that the MC simulation based on the use of the effective energy loss function describes successfully Ag 3d XPS spectrum, we applied the MC simulation to the angular distribution of Ag 3d X-ray photoelectrons for different incidence angles of X-rays, and for different take-off angles of photoelectrons. The simulation results agree very well the experimental data for small and medium incidence angle; but there is a large discrepancy for X-ray glancing incidence due to stronger surface generations of photoelectrons in this case.

Intense heavy ion beams have been produced from IMP 14.5 GHz LECR3 by optimization of the ion source conditions and transmission efficiency. Highly charged stable beams, such as 325 eμA of Ar11+, 95 eμA of Xe26+, 7 eμA of Xe30+, 140 eμA of Fe13+, and 75 eμA of Ni12+, were obtained by 14.5 GHz rf power 800–1000 W. Furthermore, an advanced superconducting ECR ion source named SECRAL is being constructed. SECRAL is designed to operate at rf frequency 18–28 GHz with axial mirror magnetic fields 4.0 T at injection, 2.2 T at extraction, and sextupole field 2.0 T at the plasma chamber wall. The unique feature of this superconducting ECR source is that the sextupole is located outside of the three axial solenoid coils to reduce the interaction force and make the source more compact. Fabrications of the superconducting coils, cryostat, beam transmission line, and other components are almost completed. Tests of the superconducting magnet with sextupole and solenoid coils are under way.

The microstructure of the extruded Mg-1Zn alloy doped with different content of manganese was analyzed by optical microscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray diffractometry. The mass-loss immersion method and electrochemical test were used to evaluate the corrosion properties. The results show that the microstructure of the extruded Mg-1%Zn-x%Mn (mass fraction, x=0.4, 0.8, 1.2) alloys consists of α-Mg and α-Mn, the grain size of α-Mg decreases with increasing Mn content. Electrochemical corrosion behavior of the alloys is similar. Mn has considerable effect on the corrosion rate, the corrosion process is exacerbated by the galvanic corrosion occurred at interface between α-Mg and α-Mn. The corrosion rate increases as the Mn content increases. Mg-1%Zn-0.4% Mn alloy exhibits the best corrosion resistance between the Mg-1%Zn-x%Mn alloys

To explore the efficacy and safety of CT-guided radioactive Iodine-125 seed implantation in treating mediastinal tumors in the thorax with artificial pneumothorax.Artificial pneumothorax was created using the 22 G thoracic puncture needle in 36 patients with mediastinal tumors, followed by CT-guided radioactive Iodine-125 seed implantation. An equal volume of gas was extracted after the treatment.The treatment was completed in 35 patients. The tumor target volumes for the radiation treatment were not significantly different before and after the artificial pneumothorax (p = 0.265). No severe complications such as refractory pneumothorax, hemoptysis, or diffuse hemorrhage in the implantation area was observed.Artificial pneumothorax can reduce the CT image interference caused by the needle tract bleeding during the radioactive Iodine-125 implantation.

Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10-8), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10-11) and 8q12 (minimum p value 1.82×10-11) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. "Replication-level" association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.

At Institute of Modern Physics, a cw 35 keV, 20 mA intense proton source and the low energy beam transport system (LEBT) have been developed for China Initiative Accelerator Driven Sub-Critical reactor system. In order to ensure high quality transmission of the intense ion beam from the exit of ion source to Radio Frequency Quadrupole (RFQ), a low energy beam transport line is used to focus beam to the RFQ entrance and match the Twiss parameters to the RFQ requirements. The 35 keV, 20 mA ion beam extracted by a three-electrode extraction system from the ion source passes through the LEBT to the RFQ entrance and the root-mean-square emittance is measured to be less than 0.2 π mm mrad. The commissioning results of the ion source and low energy beam transport system are described in this paper. The beam quality and transmission efficiency are also studied.

For a surface localized nano-structure, the XPS quantification based only on peak intensity analysis is inaccurate. In this work, we have developed an algorithm that is more elaborate and convenient for application to XPS quantification of nanoscale thin film on substrate by considering the background in a region of about 100eV following the film signal peak. A W/SiO 2 overlayer sample is investigated in this work. Theoretical evaluation of the spectra is compared with the experimental result and a pertinent algorithm is derived for application to the film thickness analysis.

A low energy beam transport (LEBT) system has been built for a compact pulsed hadron source (CPHS) at Tsinghua University in China. The LEBT, consisting of two solenoids and three short-drift sections, transports a pulsed proton beam of 60 mA of energy of 50 keV to the entrance of a radio frequency quadrupole (RFQ). Measurement has shown a normalized RMS beam emittance less than 0.2 π mm mrad at the end of the LEBT. Beam simulations were carried out to compare with the measurement and are in good agreement. Based on the successful CPHS LEBT development, a new LEBT for a China ADS projector has been designed. The features of the new design, including a beam chopper and beam simulations of the LEBT are presented and discussed along with CPHS LEBT development in this article.

We have designed and built an emittance scanner which was installed at the beam line of IMP LECR3. The scanner measures the emittance of ECR ion source by the method of electric-sweep, typically named as Electric-Sweep Scanner (ESS). The horizontal and vertical emittances were both measured by two ESSs at the beam line of IMP LECR3. Some preliminary results were obtained. The detailed results and discussions will be presented.

Many experiments have been made to produce metallic ion beams since 1998 at IMP (Institute of Modern Physics). We have designed a small oven that can reach a temperature of more than 1300 °C using 110 W electric power. Typical ion beam currents of 70 eμA of Ca12+, 60 eμA of Mg8+, 25 eμA of Pb27+ have been provided to the IMP cyclotron operation by the LECR2 (LanZhou ECR No. 2). We have also obtained some good results by the metallic ions from volatile compounds method on LECR3 (LanZhou ECR No. 3).

Laser amplification in plasma, including stimulated Raman scattering amplification and strongly coupled stimulated Brillouin scattering (sc-SBS) amplification, is very promising to generate ultrahigh-power and ultrashort laser pulses. But both are quite complex in experiments: at least three different laser pulses must be prepared; temporal delay and spatial overlap of these three pulses are difficult. We propose a single pulse compression scheme based on sc-SBS in plasma. Only one moderately long laser is applied, the front part of which ionizes the gas to produced plasma, and gets reflected by a plasma mirror at the end of the gas channel. The reflected front quickly depletes the remaining part of the laser by sc-SBS in the self-similar regime. The output laser is much stronger and shorter. This scheme is at first considered theoretically, then validated by using 1D PIC simulations.

Vegetative growth and reproductive growth strongly competes with each other during panicle development in litchi (Litchi chinensis Sonn.). We herein investigated the roles of hydrogen peroxide and nitric oxide in the competition between growth of rudimentary leaves and panicle development. The results show that the chilling-induced flowering increased H2O2 and NO contents in the mixed buds. Treatments with sodium nitroprusside (SNP), the NO donor, and methyl viologen dichloride hydrate (MV), the superoxide generator, increased NO and H2O2 contents in the mixed buds. MV and SNP treatments promoted abscission of rudimentary leaves and encouraged panicle development before or at the stage of panicle emergence. The nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) and the H2O2 trapper dimethylthiourea (DMTU) inhibited a chilling-induced flowering. SNP promoted the expression of litchi LEAFY homolog (LcLFY). These promotive effects were suppressed by the NO scavenger, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl3-oxide (PTIO) and the H2O2 trapper, DMTU. The results suggest that H2O2 and NO promote reproductive growth by inhibiting the growth of rudimentary leaves as well as by promoting the expression of the flower related gene, LcLFY.

Electron cyclotron resonance (ECR) ion sources are used for cyclotron complex and atomic physics research at the Institute of Modern Physics (IMP). Intense beams of highly charged gaseous and metallic ions could be produced by the IMP 14.5 GHz ECR ion source (LECR2-Lanzhou Electron Cyclotron Resonance Ion Source No. 2). A particular emphasis has been put on the production of metallic ion beams recently. Metallic ion beams of Mg, Ca, Fe, Ni, Cu, Zn, and Pb were tested at the IMP 14.5 GHz ECR ion source (LECR2) to improve beam intensities and long-term stability. A new ECR ion source (Lanzhou Electron Cyclotron Resonance Ion Source No. 3), an upgraded version of the IMP 14.5 GHz ECR (LECR2) but with double-frequency wave heating (10 GHz+14.5 GHz), is under commissioning. The preliminary results of this new source will be presented. To satisfy the requirements of the heavy ion cooling storage ring that is under construction at IMP, a fully superconducting ECR ion source (Lanzhou Electron Cyclotron Resonance ...

The high risk of recurrence in post-operative hepatocellular carcinoma (HCC) highlights the need for an effective adjuvant treatment. A systematic review of randomised controlled trials (RCTs) was performed to evaluate the clinical efficacy of adjuvant adoptive immunotherapy (AIT) for post-operative HCC patients. Electronic (MEDLINE, EMBASE and Cochrane Library databases) and manual searches were conducted throughout May 2011 to identify RCTs evaluating postoperative AIT for patients with HCC. Methodological quality was assessed in accordance with the QUOROM statement. Four RCTs totalling 423 patients met the eligibility criteria. All RCTs reported significantly improved disease-free survival rate or reduced recurrence rate after treating with adjuvant AIT (p0.05). The overall survival rates of AIT group are slightly higher than those of the control group in one study. Moreover, AIT was a safe treatment, with fever as the main adverse effects. This study adds to the evidence that postoperative HCC patients treated with adjuvant AIT show an improvement in disease-free survival rate or recurrence rate.

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.

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.

Seroconversion from hepatitis B surface antigen (HBsAg) to antibodies against HBsAg (anti-HBs) usually indicates resolution of hepatitis B virus (HBV) infection. Here, two HBV-infected patients with seroconversion to anti-HBs were found to be persistently positive for HBeAg and HBV DNA. Immunohistology of liver biopsies confirmed the expression of HBV proteins in the liver of one patient. The neutralizing ability of anti-HBs in patient sera was demonstrated by blocking HBV infection of primary tupaia hepatocytes. Analysis of the HBsAg-encoding region of HBV isolates from patients indicated the coexistence of heterogeneous HBV genomes in patients. The majority of recombinant variant HBsAg was reactive in HBsAg assays and was able to bind to anti-HBs. Circulating immune complexes (CIC) of HBsAg in patient sera could be detected by polyethylene glycol precipitation and trypsin digestion. Thus, neutralizing anti-HBs may appear in chronic HBV carriers for long periods but does not necessarily lead to complete viral clearance.

Some of the methods of slices satisfying moment equilibrium derived for circular slip surfaces have been extended to accommodate noncircular (or composite) type slip surfaces. A question arises regarding the point about which moment equilibrium should be taken and whether varying the center for moment equilibrium has a significant effect upon the computed factor of safety. This paper addresses the question of the effect of the center for moment equilibrium as it pertains to noncircular (or composite) slip surfaces. In particular, extensions of the Ordinary, Bishop's simplified, and the General Limit Equilibrium (GLE) methods are examined. The results show that considerable variations in the factor of safety can occur when using the extended Ordinary method. The extended Bishop's simplified method shows varying factors of safety as the moment axis moves vertically. Variations in the computed factor of safety can generally be expected to be less than 12%. The GLE, Morgerstern–Price, and Spencer methods are independent of the axis for moment equilibrium. Key words : slope stability, limit equilibrium, moment equilibrium, factor of safety, noncircular slip surface.

The epitaxial-grown diamond thin film on a natural diamond (111) substrate from a mixture of hydrogen and acetone by hot-filament-assisted CVD is studied. The deposited thin film is characterized by REM, RHEED, SEM, optical microscopy, the Laue method, Raman spectroscopy and X-ray topography. The deposited film is found to be completely epitaxial to the substrate with good crystallinity and a high degree of surface smoothness in a deposition area of about 4 mm2. No grown defect is observed except regular cleaving grooves formed during growth. REM has been employed for the characterization of the surface fine structure. It is shown that the growth of the (111) thin film occurred by the lateral motion of two sets of straight steps of atomic height consisting of (112) and (110) planes in the surface normal. This lateral epitaxial-grown pattern accounts well for the formation of large-area (111) single-crystal thin film with high quality.

This paper analyzes the inherent contradictions that exist in most of the conventional approaches disposing of dishware problem in student refectory, and presents an effective approach, based on axiomatic design (AD) and systematic inventive thinking (SIT). In the process of searching for a cost effective solution, the hierarchy framework of AD provides a framework for the application of SIT and a logical structure for problem orientation of SIT. SIT is introduced into the AD framework for removing functional dependency and searching for an uncoupled design, when the system hierarchy has been created and the interdependent functional requirements (FRs) have been found out by AD framework. SIT provides a set of thinking tools and principles. Thinking tools can lead designers to break the conventional thinking pattern and also shorten the path for a satisfied solution. Through the proposed uncoupling procedure, we can obtain a solution avoiding measuring functional dependency, harmonizing parameters, or searching substitutable technological ideas. The operational solution to dishware problem avoids the disadvantages of very poor cost effectiveness and crowded student refectory. The developed concept is based upon enlisting the students to disposing of the dishware problem successfully by taking away the dishware by the way after dinning. The detailed technological and operational concept is described, including: operation modes, implementation method, 3D representation of student refectory etc.

We report the first observation to our knowledge of coherent emission at 473 nm from an intracavity-doubled Nd:YAG microlaser. The d32 coefficient of potassium niobate was used in a 90-deg, temperature-tuned, Type I phase-matching configuration to generate the second harmonic of the 946-nm intracavity field. Output powers in excess of 5 mW at optical conversion efficiencies of approximately 2% have been observed with dye-laser pumping at 588 nm.

Abnormally increased subthalamic nucleus output to the internal pallidal segment and the reticular part of the substantia nigra plays a critical pathophysiological role in the development of parkinsonism. Because synaptic transmission of subthalamic output is glutamatergic and mediated, in part, by the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) subtype of glutamate receptor, AMPA receptor antagonists may possess antiparkinsonian properties. We report that in monoamine-depleted rats, 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX) (Novo-Nordisk, Copenhagen, Denmark)--a selective antagonist of the AMPA subtype of glutamate receptor--suppressed muscular rigidity but had no effect on akinesia. NBQX microinjected into the subthalamic nucleus, internal pallidal segment, and reticular part of the substantia nigra, but not into the laterodorsal neostriatum of the rats, stimulated locomotor activity and reduced muscular rigidity. In aged Rhesus monkeys with bilateral 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonism, intramuscular NBQX produced clinically apparent improvement in akinesia, tremor, posture, and gross motor skills. NBQX also potentiated the antiparkinsonian effects of L-3,4-dihydroxyphenylalanine in both rats and monkeys. Blockade of excitatory synaptic transmission by AMPA receptor antagonists may provide a new therapeutic strategy for Parkinson's disease (PD).

Long-time precursors of order 5 times the global energy confinement time are observed for disrupting plasmas at the high-density limit on the Texas Experimental Tokamak. These precursors, occurring well in advance of any change in the plasma MHD activity, are reflected in the electron particle and heat transport along with the density fluctuation level. Enhanced microturbulence is proposed as the physical mechanism for the confinement degradation and subsequent disruption.

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.

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.

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.

Porous tin dioxide (SnO(2)) nanostructures consisting of nanoplates are prepared through thermal decomposition of the mixed solution composed of dibutyltin dilaurate and acetic acid. The aggregations of the nanoplates give rise to large macropores with the size of about 100-300 nm. These nanoplates have a wormhole-like porous structure with the size of about 4 nm and possess high surface area. X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, infrared spectroscopy, and nitrogen sorption have been employed to characterize the obtained porous structures. It is found that the obtained nanostructures exhibit excellent catalytic activity toward methanol decomposition. Such porous structures with high surface area have promising industrial applications as catalysts.

Land surface temperature (LST) retrieval has always been a key issue in the thermal infrared remote sensing research area. Landsat5 TM data with a higher spatial resolution thermal infrared band of 120 m was often used to retrieve land surface temperature. However, the fact that Landsat 5 possesses only one thermal infrared band is also a critical limitation for LST retrieval, which does not allow applying a split-window method. LST retrieval from the radiative transfer equation using in situ radiosounding data is often not practical because of the scarcity of in situ radiosounding data. Therefore in most cases, only at-satellite brightness temperature was obtained from TM6 data, which is far different from the land surface temperature. Hence the precision of land surface temperature retrieval was actually not so satisfied. While the proposal of the generalized single-channel algorithm in 2003 makes it possible to figure out land surface temperature from TM6 data with high precision. Based on this algorithm, a test for land surface temperature retrieval of Beijing region was carried out with Landsat5 TM data acquired on 6 May 2005. MODIS data received on the same date was used to compute the total atmospheric water vapor content which is necessary for the algorithm. Furthermore, the retrieving result has been validated using simultaneously measured in situ data. A significantly high precision with a root mean square deviation (rmsd) of 1.67 K has been achieved by the approach introduced in this paper, which shows the advantages of synthetically utilizing multi-satellite data.

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.

An emittance scanner named Electric‐Sweep Scanner had been designed and fabricated in IMP. And it has been set up on the LECR3 beam line for the ion beam quality study. With some development, the ESS system has become a relatively dependable and reliable emittance scanner. Its experiment error is about 10 percent. We have done a lot of experiments of emittance measurement on LECR3 ion source, and have researched the relations between ion beam emittance and the major parameters of ECR ion source. The reliability and accuracy test results are presented in this paper. And the performance analysis is also discussed.

18GHz microwave has been fed to the LECR3 ion source to produce intense highly charged ion beams although this ion source was designed for 14.5GHz. Then 1.1 emA Ar8+ and 325 eμA Ar11+ were obtained at 18GHz. During the source running for atomic physics experiment, some higher charge state ion beams such as Ar17+ and Ar18+ were detected and have been validated by atomic physics method. Furthermore, a few special gases, e.g. SiH4 and SF6, were tested on LECR3 ion source to produce required ion beams to satisfy the requirements of atomic physics experiments.

A high performance all permanent Electron Cyclotron Resonance Ion Source (ECRIS) LAPECR2 (Lanzhou All Permanent ECR ion source No. 2) has been under construction in IMP for one year. This ECRIS is running at 14.5GHz. The magnetic field configuration is designed according to the famous magnetic scaling laws: Binj = 1.4T (2.2T with an iron plug at the injection side), Bex1 = 1.1T, Bmin = 0.43T and Brad = 1.2T. According to the final design, the source body is φ650mm×560mm in dimension and about 900kg in weight. The source turns out to be the largest all permanent ECRIS in the world. To fabricate such an ion source is really very difficult, however we have succeeded in overcoming the many difficulties and the source has been set up recently. In this article, the typical parameters of the constructed ion source are presented.

Two new space charge compensation methods developed in IMP are discussed in this paper. There are negative high voltage electrode method (NHVEM) and electronegative charge gas method (EGM). Some valuable experimental data have been achieved, especially using electronegative gas method in O6+ and O7+ dramatic and stable increasing of ion current was observed.

The stripping mode for production of multi‐charged radioactive ion beams is discussed, and its advantages are also discussed. A 2.45 GHz ECRIS serving as the primary ion source was designed for production of singly charged radioactive ion beams. This source is compact, reliable, and economical. The magnetic field of the source provided by two permanent magnet rings has been calculated with POISSON code. Additionally, the structure of the source is presented.

With the development of Electron Cyclotron Resonance Ion Source (ECRIS), very high performance ECRIS nowadays have been set up one by one around the world, such as the GTS in Grenoble, SERSE in Catania, LECR3 in Lanzhou and etc, which can produce very intense Multiply Charged Ion (MCI) beam. But till now, the study of the extracted MCI beam from an ECRIS remains open. In this article, we present a theoretical and experimental study of the extracted MCI beam. In the theoretical part, the influences of the extraction system on the extracted ion beam quality are mainly analyzed. The aspects that have influences on the extracted ion beam quality have been analyzed. With the instruction of the analysis, the PBGUNS code is used to simulate the influences of some important aspects concerning the extraction system. The influences of the extraction system geometry design, magnetic field, and the space charge effect will be detailedly presented in this article. In the experimental part, with an Electric‐Sweep Scanner (ESS) emittance detection system, the influences on the extracted ion beam emittance of some typical parameters of ECRIS have been researched, such as the injected RF power, the RF frequency, the magnetic field and etc. The obtained results and the corresponding explanations are presented. Some of the results are well in accord with some empirical laws, but some other results seem to be disputed.

To study the relationship between Fo and true or falsetto range in four phonation modes.Testing Fo of lowest true voice, comfortable voice, highest true voice and falsetto voice.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.Fo of falsetto highest voice reduces, falsetto voice rang become thin in pathological voice.

The effects of glutamate on the transient outward potassium current of dissociated hippocampal CA(1) neurons of 7-10 d rats were studied by the whole-cell patch clamp technique. It was found that glutamate could block the transient potassium current in a dose- and time-dependent manner. The effect was partly voltage-dependent. These results suggest that glutamate may decrease the membrane conductance of K(+) channels in hippocampal neurons.