Xia li

Chongqing Medical University · pediatricd

Objective: To evaluate the application of a mobile platform-based system in the management of fundus disease in outpatient settings. Methods: In the outpatient departments of fundus disease, premature babies requiring eye examination under general anesthesia and adults requiring intraocular surgery were enrolled as the subjects. According to the ex...

A 2.45 GHz intense pulsed ECR proton source and low energy beam transport (LEBT) system was developed by Tsinghua University for the compact pulsed hadron source (CPHS). The proton injector provides proton beam into a 3.2 MeV RFQ accelerator. The 50 keV/75 mA hybrid beam extracted by a 4-electrode extraction system from the ion source passes throug...

A high intensity ECR proton source with 14 GHz microwave heating was proposed and successfully developed at IMP. In 2013, the experimental platform was set up and the preliminary commissioning was performed. The experimental results indicate that the source can produce a total of 4 mA CW hydrogen beams with microwave power of 200 W and extraction v...

The measurement of cosmic ray energy spectra, in particular for individual species, is an essential approach in finding their origin. Locating the "knees" of the spectra is an important part of the approach and has yet to be achieved. Here we report a measurement of the mixed Hydrogen and Helium spectrum using the combination of the ARGO-YBJ experi...

A negative hydrogen (H(-)) ion source with hot cathode arc discharge was designed and fabricated as a primary injector for a 10 MeV PET cyclotron at IMP. 1 mA dc H(-) beam with ɛ N, RMS = 0.08 π mm mrad was extracted at 25 kV. Halbach hexapole was adopted to confine the plasma. The state of arc discharge, the parameters including filament current,...

The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured, below the so-called "knee", by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber (RPC) array of the ARGO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic...

The ARGO-YBJ detector is an extensive air shower array that has been used to monitor the northern $\gamma$-ray sky at energies above 0.3 TeV from 2007 November to 2013 January. In this paper, we present the results of a sky survey in the declination band from $-10^{\circ}$ to $70^{\circ}$, using data recorded over the past five years. With an integ...

We report the observation of a very high energy \gamma-ray source, whose position is coincident with HESS J1841-055. This source has been observed for 4.5 years by the ARGO-YBJ experiment from November 2007 to July 2012. Its emission is detected with a statistical significance of 5.3 standard deviations. Parameterizing the source shape with a two-d...

Excitation of the geodesic acoustic mode continuum by drift wave turbulence is studied using the wave kinetic approach. For a model profile of weak non-uniform ion temperature, the forms of growth rate and radial structure of geodesic acoustic modes are obtained analytically. The growth rate is analyzed for several conditions for present-day tokama...

Background: Macular hole retinal detachment (MHRD) causes severe decrease of vision. Pars plana vitrectomy has been applied for MHRD. Silicone oil and C3F8 have been used as intraocular tamponade materials, while there are still controversity on their efficacy. Objective: This trial was to evaluate the efficacy of vitreous surgery combined with sil...

As one of the brightest active blazars in both X-ray and very high energy $\gamma$-ray bands, Mrk 501 is very useful for physics associated with jets from AGNs. The ARGO-YBJ experiment is monitoring it for $\gamma$-rays above 0.3 TeV since November 2007. Starting from October 2011 the largest flare since 2005 is observed, which lasts to about April...

The ARGO-YBJ experiment detects extensive air showers in a wide energy range by means of a full-coverage detector which is in stable data taking in its full configuration since November 2007 at the YBJ International Cosmic Ray Observatory (4300 m a.s.l., Tibet, People’s Republic of China). In this paper the measurement of the light-component spectr...

A new room temperature electron cyclotron resonance (ECR) ion source, DRAGON, is under construction at IMP. DRAGON is designed to operate at microwaves of frequencies of 14.5-18 GHz. Its axial solenoid coils are cooled with evaporative medium to provide an axial magnetic mirror field of 2.5 T at the injection and 1.4 T at the extraction, respective...

The structure and preliminary commissioning results of a new 2.45 GHz ECR proton ion source and a dual-lens low energy beam transport (LEBT) system are presented in this paper. The main magnetic field of the ion source is provided by a set of permanent magnets with two small electro-solenoid magnets at the injection and the extraction to fine tune...

A laser (Nd:YAG laser, 3 J, 1064 nm, 8-10 ns) ion source has been built and under development at IMP to provide pulsed high-charge-state heavy ion beams to a radio frequency quadrupole (RFQ) for upgrading the IMP accelerators with a new low-energy beam injector. The laser ion source currently operates in a direct plasma injection scheme to inject t...

Ion beam transport from the Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) electron cyclotron resonance ion source was studied at the Institute of Modern Physics during 2010. Particle-in-cell simulations and experimental results have shown that both space charge and magnetic aberrations lead to a la...

Cosmic ray antiprotons provide an important probe to study the cosmic ray propagation in the interstellar space and to investigate the existence of dark matter. Acting the Earth-Moon system as a magnetic spectrometer, paths of primary antiprotons are deflected in the opposite sense with respect to those of the protons in their way to the Earth. Thi...

A wide field of view Cherenkov/fluorescence telescope array is one of the main components of the Large High Altitude Air Shower Observatory project. To serve as Cherenkov and fluorescence detectors, a flexible and mobile design is adopted for easy reconfiguring of the telescope array. Two prototype telescopes have been constructed and successfully...

The charge readout of Resistive Plate Chambers (RPCs) is implemented in the ARGO-YBJ experiment to measure the charged particle density of the shower front up to 10(4)/m(2), enabling the study of the primary cosmic rays with energies in the "knee" region. As the first time for RPCs being used this way, a telescope with RPCs and scintillation detect...

The ARGO-YBJ experiment at YangBaJing in Tibet (4300 m a.s.l.) has been taking data with its full layout since October 2007. Here we present a few significant results obtained in gamma-ray astronomy and cosmic-ray physics. Emphasis is placed on the analysis of gamma-ray emission from point-like sources (Crab Nebula, MRK 421), on the preliminary lim...

Detecting and monitoring emissions from flaring gamma-ray sources in the very-high-energy (VHE, 4 100 GeV) band is a very important topic in gamma-ray astronomy. The ARGO-YBJ detector is characterized by a high duty cycle and a wide field of view. Therefore, it is particularly capable of detecting flares from extragalactic objects. Based on fast re...

Detecting and monitoring emissions from flaring gamma-ray sources in the very-high-energy (VHE, > 100 GeV) band is a very important topic in gamma-ray astronomy. The ARGO-YBJ detector is characterized by a high duty cycle and a wide field of view. Therefore, it is particularly capable of detecting flares from extragalactic objects. Based on fast re...

Shear flows induced by the nonlinear evolution of double tearing modes are studied numerically using Hall magnetohydrodynamics simulations in a slab geometry. The Hall effect is shown to plays an important role when the thickness of current sheets decrease and falls in the range of ion inertia length d i . Effective shear flows in the magnetic isla...

The primers for amplifying various lengths of human PrP and HAX-1

To gain a comprehensive understanding of plant response to Cd, physiological and proteomic changes in wheat (Triticum aestivum L.) leaves exposed to a range of Cd concentrations (10, 100 and 200 μM) were investigated. Leaf elongation was decreased, whereas the H2O2 and malondialdehyde content increased significantly at higher Cd concentrations. Cha...

Electron-loss cross sections in Cq+(q=1-4)collisions with He, Ne, Ar are measured in the intermediate-velocity regime, and the ratio of the two-electron-loss cross section to the one-electrom-loss cross section, R21, are calculated. It is shown that a single-channel analysis is not sufficient to explain the results, and that projectile electron los...

Cosmic rays are hampered by the Moon and a deficit in its direction is expected (the so-called Moon shadow). The Moon shadow is an important tool to determine the performance of an air shower array. Indeed, the westward displacement of the shadow center, due to the bending effect of the geomagnetic field on the propagation of cosmic rays, allows th...

ARGO-YBJ is an air shower detector array with a fully covered layer of resistive plate chambers. It is operated with a high duty cycle and a large field of view. It continuously monitors the northern sky at energies above 0.3 TeV. In this paper, we report a long-term monitoring of Mrk 421 over the period from 2007 November to 2010 February. This so...

We show that entangled entanglement can be obtained from a multimode Raman laser. In this system, all lasing modes constitute a quantum-beat. Equivalently, one collective mode is operated well above threshold and exhibits the sub-Poissonian statistics, while other orthonormal collective modes are excluded from the interacting system and stay in vac...

Prion protein (PrP) is a ubiquitous conserved glycoprotein predominantly expressed in neurons of the central nervous system (CNS). To elucidate on its cellular function, we performed a yeast two-hybrid screen within an adult human brain cDNA library for potential PrP-binding molecules. A novel protein, HS-1 associated protein X-1 (HAX-1), was ide...

The PrP patterns in the cells transiently expressing PrP-WT, PrP-A117V, PrP-G114V, PrP-E200K or PrP-P102L prior to the treatments of PK and PNGase F (left panel) and digested with PNGase F alone (right panel) in Western blot. Various PrP constructs were indicated at bottom. (1.03 MB TIF)

The sun blocks cosmic ray particles from outside the solar system, forming a detectable shadow in the sky map of cosmic rays detected by the ARGO-YBJ experiment in Tibet. Because the cosmic ray particles are positive charged, the magnetic field between the sun and the earth deflects them from straight trajectories and results in a shift of the shad...

SECRAL (Superconducting ECR ion source with Advanced design in Lanzhou) is an advanced superconducting ECR ion source built with an innovative solenoid-inside-sextupole structure in 2005. Since 2007, SECRAL has delivered a good variety of highly-charged ion beams to HIRFL (Heavy Ion Research Facility in Lanzhou), such as 129 Xe 27+ ， 78 Kr 19+ ， 20...

The Large High Altitude Air Shower Observatory project is proposed to study high energy gamma ray astronomy ( 40 GeV-1 PeV ) and cosmic ray physics ( 20 TeV-1 EeV ). The wide field of view Cherenkov telescope array, as a component of the LHAASO project, will be used to study energy spectrum and compositions of cosmic ray by measuring the total Cher...

In 2008, the blazar Markarian 421 entered a very active phase and was one of the brightest sources in the sky at TeV energies, showing frequent flaring episodes. Using the data of ARGO-YBJ, a full coverage air shower detector located at Yangbajing (4300 m a.s.l., Tibet), we monitored the source at gamma-ray energies E>0.3 TeV during the whole year....

Phospho-tau deposition has been described in a rare genetic human prion disease, Gerstmann-Sträussler-Scheinker syndrome, but is not common neuropathological picture for other human and animal transmissible spongiform encephalopathies (TSEs). This study investigated the possible changes of tau and phosphorylated tau (p-tau, at Ser396, Ser404, and S...

In the condition of reactor scale plasma, the influence of incident wave power density on electron cyclotron current drive and power deposition is studied with the relativistic Fokker-Planck equation incorporated into a beam-tracing code. The results show that current drive efficiency is reduced slightly; power deposition profile is broaden and mov...

A numerical simulation of electron cyclotron current drive under ITER (International Thermonuclear Experimental Reactor) parameters was performed with the relativistic Fokker-Planck equation incorporated into a ray tracing code. While the toroidal incident angles are not very large, the wave power deposits in the high-filed-side of ITER. While the...

Superconducting electron cyclotron resonance ion source with advance design in Lanzhou (SECRAL) is an 18–28 GHz fully superconducting electron cyclotron resonance (ECR) ion source dedicated for highly charged heavy ion beam production. SECRAL, with an innovative superconducting magnet structure of solenoid-inside-sextupole and at lower frequency an...

Superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is an all-superconducting-magnet electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged ion beams to meet the requirements of the Heavy Ion Research Facility in Lanzhou (HIRFL). To further enhance the performance of...

Annexin A1 (ANXA1) is a calcium- and phospholipid-binding protein and is considered to play an important role in tumorigenesis. However, the correlation between ANXA1 expression and tumor clinicopathological features in patients with breast cancer remains unclear. This study investigated the prognostic value of ANXA1 protein as breast cancer marker...

Three different ionic liquids (ILs) were used for the crystallization of lysozyme and thaumatin. It would be a promising solvent for applications in protein chemistry, due to its unusual features such as excellent solubility of inorganic and organic materials, enhancement of protein activity and stability, etc. Here, [BMIm][BF4] was used as precipi...

The proton-air cross section in the energy range 1–100 TeV has been measured by the ARGO-YBJ cosmic ray experiment. The analysis is based on the primary cosmic ray flux attenuation for different atmospheric depths (i.e. zenith angles) and exploits the detector capabilities of selecting the shower development stage by means of hit multiplicity, dens...

To report eight cases of central mucoepidermoid carcinoma of the jaws (CMCJ) and to analyze its clinical and pathological features. Eight cases of central mucoepidermoid carcinoma were diagnosed between 1989 and 2008. The clinical manifestation, radiological and histopathological changes were analyzed. The mean age of this group of patients was 43....

The ARGO-YBJ experiment has been taking data for nearly 2 years. In order to monitor continuously the performance of the Resistive Plate Chamber detectors and to study the daily temperature effects on the detector performance, a cosmic ray muon telescope was setup near the carpet detector array in the ARGO-YBJ laboratory. Based on the measurements...

Two rice (Oryza sativa L.) cultivars differing in chilling sensitivity, Changbaijiu (chilling-tolerant) and Zhongjian (chilling-sensitive) were pre-treated with 0.5, 1.0 and 2.0 mM salicylic acid (SA) for 24 h before chilling at 5°C for 1 d. Chilling induced SA accumulation, particularly conjugated SA in both leaves and roots of the two rice cultiv...

To compare the effect of intravitreal bevacizumab vs intravitreal triamcinolone for the treatment of non-ischaemic central retinal vein occlusion (CRVO). The comparative nonrandomized retrospective clinical interventional study included 72 patients with non-ischaemic CRVO, divided into a bevacizumab group of 30 patients (1.25 mg bevacizumab) and a...

To investigate the hot electrons in highly charged electron cyclotron resonance (ECR) plasma, Bremsstrahlung radiations were measured on two ECR ion sources at the Institute of Modern Physics. Used as a comparative index of the mean energy of the hot electrons, a spectral temperature, Tspe, is derived through a linear fitting of the spectra in a se...

Soft tissue clear cell sarcoma usually occurred in the end of the limbs, especially foot and ankle. Soft tissue clear cell sarcoma occurring in the torso and head and neck were even fewer. In this article, parapharyngeal soft tissue clear cell sarcoma was reported.

The ARGO-YBJ (Astrophysical Radiation Ground-based Observatory at YangBaJing) experiment is designed for very high energy γ-astronomy and cosmic ray researches. Due to the full coverage of a large area (5600 m2) with resistive plate chambers at a very high altitude (4300 m a.s.l.), the ARGO-YBJ detector is used to search for transient phenomena, su...

Many factors have effects on crystallization. The major influencing factors during protein crystallization are summarized in this paper. Recommendations are made about the basic process of crystallization and the analysis of the thermodynamic effects on crystallization, and the dynamics factors effecting crystallization during an equilibrium proces...

In this paper, the effective area of the ARGO‐YBJ experiment to detect the gamma rays with energy range from 10 GeV to 1 TeV for different incident zenith angles (0,10,20,30,40 degrees) is given respectively. The optimal event selections to search for GRB counterparts with different cutoff energy models ( Ecut = 100 GeV and 1 TeV) are studied. U...

The ARGO-YBJ experiment is a full coverage array made of Resistive Plate Chambers (RPCs) operated in streamer mode to detect the extensive array showers (EASs). With large field of view (>2sr) and high duty cycle (>90%), the ARGO-YBJ detector is the right ground-based apparatus to detect VHE GRBs, while the high altitude (4300 m a.s.l) and scaler w...

Posttraumatic stress disorder (PTSD) is one of the most common psychiatric disorders. Despite the extensive study of the neurobiological correlates of this disorder, the underlying mechanisms of PTSD are still poorly understood. Recently, a study demonstrated that dexamethasone (Dex), a synthetic glucocorticoid, can up-regulate p11, known as S100A1...

An optical imaging based fully automatic stereo vision system for aircraft assembly online measurement is presented and analyzed. In this system, the relative position of the two cameras can easily calibrated by imaging an optical reference bar in different locations and orientations throughout the measurement space according to epipolar constraint...

Guidelines on oxygenation policies and on the prevention and treatment of retinopathy of prematurity (ROP) were issued by the Chinese Medical Association in 2004. This study was undertaken to determine the incidence of and risk factors for ROP among preterm infants in Beijing, the capital of China, after implementation of the guidelines. Neonates w...

In order to investigate the hot electron component in electron cyclotron resonance (ECR) plasmas, the volume bremsstrahlung spectra in the x-ray photon energy range were measured with a high-purity germanium detector on Lanzhou ECR Ion Source No. 2 Modified (LECR2M). A collimation system similar to Bernhardi's was used to focus at the central part...

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 han...

Extreme ultraviolet lithography (EUVL) is considered as the most promising solution at and below dynamic random access memory 32 nm half pitch among the next generation lithography, and EUV light sources with high output power and sufficient lifetime are crucial for the realization of EUVL. However, there is no EUV light source completely meeting t...

A 320 kV high voltage (HV) platform has been constructed at Institute of Modern Physics (IMP) to satisfy the increasing requirements of experimental studies in some heavy ion associated directions. A high charge state all-permanent magnet ECRIS-LAPECR2 has been designed and fabricated to provide intense multiple charge state ion beams (such as 1000...

The amplification and cloning of promoters are regularly employed procedures to study the mechanism of gene regulation. In the present study we developed a method to construct T-vectors used for the direct and unidirectional cloning and analysis of promoters. These so-called T-vectors, pEGFP-T and pGL3-T, were derived from their parent promoterless...

Tanshinone IIA (TSA) is a major constituent of Salvia miltiorrhiza Bunge widely used in the treatment of stroke. This current study aimed to investigate the nature of brain penetration of TSA using several in vitro and in vivo models. The uptake and efflux of TSA in primary rat brain microvascular endothelial cells (RBMVECs) were altered in the pre...

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 th...

The recently developed SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) ion source is a high-performance nextgeneration 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 pla...

The objective of this research was to discuss the influence of pretreatment on the result of mineralogical analysis for low mass dust aerosol samples. Three dust aerosol samples were collected at Dunhuang during three dust storm events in spring, 2002. Each sample was operated by the pretreatment method and X-ray diffraction experiment for five tim...

Diffuse reflectance spectrometry was used to study iron-oxide minerals and to investigate the reflectance characteristics of eolian dust collected during the spring of 2001 and 2002 on bulk filters from three sites in northern China. The first derivatives of the reflectance spectra were consistent with signals from two iron-oxide minerals, hematite...

With a latest developed electric-sweep scanner system, we have done a lot of experiments for studying this scanner system and ion beam emittance of electron cyclotron resonance (ECR) ion source. The electric-sweep scanner system was installed on the beam line of Lanzhou electron resonance ion source No. 3 experimental platform of Institute of Moder...

Superconducting electron cyclotron resonance (ECR) ion source with advanced design in Lanzhou (SECRAL) is a next generation ECR ion source and aims for developing a very compact superconducting ECR ion source with a structure and high performances for highly charged ion-beam production. The ion source was designed to be operated at 18 GHz at initia...

Electron cyclotron resonance (ECR) ion sources have been used for atomic physics research for a long time. With the development of atomic physics research in the Institute of Modern Physics (IMP), additional high performance experimental facilities are required. A 300 kV high voltage (HV) platform has been under construction since 2003, and an all...

To study the injection of additional electrons from an external electron gun into the plasma of a Penning ionization gauge (PIG) ion source, a test bench for the external electron-beam enhancement of the PIG (E-PIG) ion source was set up. A source magnet assembly was built to satisfy the request for magnetic field configuration of the E-PIG ion sou...

In order to diagnose the electron cyclotron resonance (ECR) plasma, electron bremsstrahlung spectra were measured by a HPGe detector on Lanzhou ECR Ion Source No. 3 at IMP. The ion source was operated with argon under various working conditions, including different microwave power, mixing gas, extraction high voltage (HV), and so on. Some of the me...

Uranium ion beams were produced from electron cyclotron resonance (ECR) ion sources by sputtering method this year at the Institute of Modern Physics. At first, we chose the Lanzhou ECR No. 3 ion source to implement the production experiment of U ion beams. Finally, 11 e μA of U28+, 5 e μA of U32+, and 1.5 e μA of U35+ were obtained. A U26+ ion bea...

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 bee...

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...

A low concentration (10 nM) of adenosine potentiated hippocampal neuronal activity via A(2a) adenosine receptors without affecting presynaptic glutamate release or postsynaptic glutamatergic conductance. Adenosine inhibited glutamate uptake through the glial glutamate transporter, GLT-1, via A(2a) adenosine receptors. In addition, adenosine stimula...

A new electron cyclotron resonance (ECR) ion source (LECR3—Lanzhou Electron Cyclotron Resonance Ion Source No. 3) has been constructed this year. The main purpose of this source is to provide highly charged ion beams for atomic physics and surface physics research. The design of this ion source is based on the IMP 14.5 GHz ECR ion source (LECR2—Lan...

Polymorphism of the dopamine receptor type-2 (D(2)) gene is associated with essential hypertension. To assess whether D(2) receptors participate in regulation of blood pressure (BP), we studied mice in which the D(2) receptor was disrupted. In anesthetized mice, systolic and diastolic BPs (in millimeters of mercury) were higher in D(2) homozygous a...

To determine if the defective interactions among D(1)-like receptors, G proteins, and Na(+)/H(+) exchanger 3 (NHE3) are consequences of hypertension, we studied these interactions in rats, before (2--3 wk) and after (12 wk) the establishment of hypertension. To eliminate the confounding influence of second messenger action on D(1) receptor-NHE3 int...