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A significant deceleration effect on a stored coasting ion beam by a continuous-wave laser light was observed in the Schottky-noise spectrum during the laser experiments with lithium-like oxygen ion beams stored at a relativistic energy of 275.7 MeV/u at the heavy-ion storage ring CSRe in Lanzhou, China. The observed deceleration range of the laser (Δp/p≈5.7×10−6) is much broader than the expected capture range (Δp/p≈3.6×10−8), as calculated from the natural linewidth of the O5+ ion’s electronic transition (2S1/2 −2 P1/2). In order to explain this huge deviation, a phase space tracking code has been developed to investigate the interaction between the stored coasting ion beam and the laser light. Simulations reveal that the deceleration range of the typically narrow CW laser force is highly enlarged by taking into account the transverse betatron oscillation of the ions with larger emittance and the angular misalignment of the laser light direction. The experimental observation is well described by the systematic simulations. The present work is crucial for forthcoming laser cooling and precision laser spectroscopy experiments and simulations on heavy highly charged ions at the CSRe and the future facility HIAF.

Purpose/Objective(s) This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based regimens in a real-world cohort of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL). Materials/Methods In the modern era, we identified 376 patients who received combined radiotherapy with either ASP-based (asparaginase, platinum and gemcitabine, n = 286) or non-ASP-based (platinum and gemcitabine, n = 90) regimens. The patients were stratified into low-, intermediate- and high-risk groups using the early stage-adjusted nomogram-revised risk index (ES-NRI). Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses. Results ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% vs. 73.2%, P = 0.021) and DMFS (84.4% vs. 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients. Moreover, ASP-based regimens decreased DM, with 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based regimens remained consistent after adjusting the confounding variables by IPTW and multivariate analyses. Additional sensitivity analyses confirmed these results. Conclusion These findings provide an evidence supporting ASP-based regimens as a first-line combined-modality treatment for intermediate- and high-risk early-stage ENKTCL.

This paper studies the buckling problem of nanowires (NWs) and carbon nanotubes (CNTs) freely standing on a substrate and subjected to distributed axial loads. NWs and CNTs are modeled as elastic nanocolumns and due to their high Young's modulus, the substrate is reasonably considered as an elastic foundation. The junction between the nanocolumn and substrate is described by a rotational spring. A new approach is suggested to solve the stability of axially-loaded nanocolumns with a rotational spring junction. An approximation expression for the critical load with high accuracy is derived in closed form. The results are confirmed for a rectangular Ag NW by FEM. Numerical results of the critical length of NWs and CNTs under their own weight are presented in graphs and tables. Obtained results indicate that the critical length is sensitive to small Young's modulus of the elastic substrate and becomes insensitive for enough large Young's modulus of the elastic substrate. When the rotational spring stiffness is sufficiently large, the case reduces to a free-standing NW on a rigid foundation.

Background Cancer-induced bone pain remains a clinical challenge due to the poor understanding of the mechanisms. Recent study revealed extracellular adenosine triphosphate (ATP) and P2X receptors may be implicated in nociceptive signalling under cancer pain state. Therefore, here we investigated the potential role of P2X3 receptor in a rat model of bone cancer pain. Methods Walker 256 tumour cells were inoculated into the left tibia of Wistar rats. The model was verified by X-ray imaging, pathology and behaviour examinations. The expression of P2X3 receptors in dorsal root ganglia (DRG) was examined. Functional significance of altered P2X3 receptors was investigated by measuring influx upon α,β-meATP stimulation in acutely dissociated DRG neurons. Moreover, A-317491, an antagonist of P2X3 receptors, was administrated intrathecally or locally to evaluate its analgesia effect in the cancer pain animals. Results The P2X3 receptor was up-regulated for about 50% in DRG neurons in rats with bone cancer at both protein and mRNA levels and correlated with the pain behaviour in bone cancer rats. A 51.9% increase of α,β-me ATP (10 μM, for 4 s) evoked transient response currents and a higher percentage of neurons responsive to the application of α,β-me ATP was detected in bone cancer rats. Intrathecal or local injection of A-317491 significantly attenuated pain behaviour induced by bone cancer. Conclusions These results suggest that the P2X3 receptor is functionally up-regulated in DRG in cancer rats. P2X3 receptor is a promising target for therapeutic intervention in cancer patients for pain management.

Titanium silicate thin films have been grown on Si substrates by photo-induced chemical vapor deposition using 222-nm ultraviolet excimer lamps. Titanium tetraisopropoxide (TTIP) and tetraethoxysilane (TEOS) were used as precursors. TTIP and TEOS were dissolved together in cyclohexane and introduced into the photochemical reaction chamber through a droplet injector vaporizer. The composition of the film was controlled by changing the ratio of TTIP to TEOS in the precursor solution. High quality titanium silicate films with various Ti/Si ratios and low carbon content have been achieved as revealed by X-ray photoelectron spectroscopy measurements. The atomic percentage of Ti content in the grown silicate films is significantly larger than that in the precursor solution. The films were measured to be 30-80 nm in thickness and 1.91-2.31 in refractive index by ellipsometry. Both the growth rate and refractive index increase with increasing Ti percentage in the silicate films. The evolution of Fourier transform infrared spectra of the silicate films with solution composition shows that the Ti-O-Si absorption at approximately 920 cm-1becomes stronger, while the Ti-O absorption at approximately 430 cm-1becomes weaker with decreasing Ti percentage in the solution. A small feature at ∼1035 cm-1related to Si-O-Si bonds is also observed in the SiO2-rich Ti silicate film. © 2003 Elsevier B.V. All rights reserved.

The ultraviolet photo-induced chemical vapour deposition (UV-photo-CVD) process is a highly flexible and efficient technique for fabrication of thin oxide films. We report in this work the deposition of Er-doped SiO2-TiO2 thin films using UV-photo-CVD at temperatures between 350 and 500degreesC. Erbium isopropoxide, titanium tetraisopropoxide (TTIP) and tetraethoxysilane (TEOS) are used as precursors. The films are measured to be around 20-100 nm in thickness with refractive indices from 1.60 to 1.90. The chemical, optical, microstructural and spectroscopic properties of the films have been investigated by Fourier transform infrared spectroscopy (FTIR), ellipsometry, photoluminescence (PL) spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). High quality as-deposited films with various Ti/Si ratios and low carbon contents have been confirmed by XPS measurement. Er-doped titanic-silica films were produced by UV-photo-CVD and effect of thermal and UV annealing on these films has also been studied. (C) 2003 Elsevier B.V. All rights reserved.

In previous work, we have grown 4–10 nm Ta 2 O 5 films by photo-induced chemical vapour deposition (photo-CVD) using a special precursor injection system, which exhibited leakage currents as low as 2.19×10 −7 A/cm 2 at 1 MV/cm. However properties of these films are known to deteriorate with decreasing film thickness. UV annealing at low temperatures using an excimer UV source can improve the electrical properties of these films dramatically. In this paper, tantalum pentoxide thin films with thicknesses of approximately 40 nm grown by photo-CVD have been annealed at low temperature using an excimer UV lamp. Film properties have been characterised using ellipsometry, Fourier transform infrared spectroscopy, UV spectrophotometry, capacitance–voltage and current–voltage techniques. After UV annealing, improved leakage current densities as low as 4.0×10 −8 A/cm 2 at 1 MV/cm, and breakdown fields higher than 3.0 MV/cm can be achieved. Investigation of the interfacial SiO x layer formed during deposition and after UV annealing by X-ray photoelectron spectroscopy and TEM reveals that thickness increases with UV annealing time and that the suboxides in the film and at the interface are converted into stoichiometric oxide, leading to an improvement of the electrical properties.

TiO 2 -doped HfO 2 thin films, as potential replacements for SiO 2 as high- k gate dielectric material, have been grown by photo-induced CVD using 222 nm excimer lamps at a temperature of 400 °C. Vaporised titanium isopropoxide and hafnium (IV) tetra- t -butoxide were used as the precursors. Films from approximately 45–70 nm in thickness with refractive indices from 1.850 to 2.424 were grown with various Ti:Hf ratios. The as-deposited films were found to be amorphous by X-ray diffraction when the Ti/(Ti+Hf) value was up to 33%, while the crystalline TiO 2 anatase phase formed when the Ti/(Ti+Hf) was 41%. We also found that the refractive index increased sharply when the Ti/(Ti+Hf) was over 25%. Fourier transform infrared spectroscopy, XPS and TEM were also used to monitor as well as the presence of Ti, interface and microstructure of the films on Si-substrate. The effect of UV-annealing on the electrical properties of these films will also be discussed.

Outliers are difficult to handle because some of them can be measurement errors, while others may represent phenomena of interest, something "significant" from the viewpoint of the application domain. Statistical and computational methods have been proposed to detect outliers, but further analysis of outliers requires much relevant domain knowledge. In our previous work (1994), we suggested a knowledge-based method for distinguishing between the measurement errors and phenomena of interest by modeling "real measurements" - how measurements should be distributed in an application domain. In this paper, we make this distinction by modeling measurement errors instead. This is a cautious approach to outlier analysis, which has been successfully applied to a medical problem and may find interesting applications in other domains such as science, engineering, finance, and economics.

We report the use of UV lamp sources, providing high photon fluxes over large-areas, to initiate the photo-deposition of ultrathin tantalum pentoxide (Ta 2 O 5 ) films with physical thickness between 4-10 nm at low temperatures (below 350°C). The photo-deposited film properties, determined using various standard methods and electrical measurements, have shown that good quality films can be produced. We have found that although a thin sub-stoichiometric silicon oxide layer (SiO x ) was present at the Ta 2 O 5 /Si interface. The electrical properties of these tantalum oxide films are significantly improved following an UV annealing step in 1000 mbar of pure oxygen. XPS profiles revealed that the SiO x layer could be transformed to SiO 2 after the UV annealing process. These XPS results are critically important for the understanding of the interface properties of the tantalum oxide films on Si in the quest to further improve the photo-CVD process.

A software-based visual-field testing (perimetry) system is described which incorporates several AI components, including machine learning, an intelligent user interface and pattern discovery. This system has been successfully used for self-screening in several different public environments.

The pitting behavior of passive 304 stainless steel in 0.25 M Na 2 SO 4 media of pH 1 containing chloride ions of different concentrations has been investigated using EIS technique. The characteristics of measured impedance spectra have been analysed. It is proposed that an intermediate complex (MOHCl)com will form in both the pit initiation and propagation stages. The reaction mechanism models for pit initiation and propagation, and an equivalent circuit model to simulate the electrode impedance in pit propagation stage have been suggested. The factors which control the pit growth kinetics have been discussed.

Deposition of Sn on the Pt(111) surface followed by annealing at 1000 K leads to the formation of ordered phases showing (2 × 2 and ( 3 × 3 ) R 30° LEED patterns, depending on the surface coverage of Sn. Both these phases were studied by LEED dynamical analysis. The best agreement between experimental and calculated I–V curves was obtained by means of models based on the formation of mixed Pt-Sn layers on the surface where Pt and Sn atoms are nearly coplanar with a slight upward buckling of Sn atoms. The structures of these phases are similar to those already observed for the Pt 3 Sn(111) surface.

One of the main difficulties in obtaining reliable data from patients in glaucomatous tests is the measurement noise caused by the learning effect, inattention, failure of fixation, fatigue, etc. Using Kohonen's self-organising feature maps, we have developed a computational method to distinguish between the noise and true measurement. This method has been shown to provide a satisfactory way of locating and rejecting noise in the test data, an improvement over conventional statistical methods. >

The effects of the substitutions of Dy and Er for Sm on the crystal structure and magnetic properties of Sm/sub 2/Fe/sub 17/ and Sm/sub 2/Fe/sub 17/N/sub y/ compounds have been investigated. The structures of (Sm/sub 1-x/R/sub x/)/sub 2/ Fe/sub 17/N/sub y/ compounds with R=Dy and Er and the hosts change from Th/sub 2/Zn/sub 17/-type to Th/sub 2/Ni/sub 17/-type with increasing Dy and Er contents. The replacement of Sm by Dy or Er results in a decrease in Curie temperature, saturation magnetization, and magnetic anisotropy field in the (Sm/sub 1-x/R/sub x/)/sub 2/Fe/sub 17/N/sub y/ compounds. A tentative spin phase diagram of the (Sm/sub 1-x/Dy/sub x/)/sub 2/Fe/sub 17/N/sub y/ compounds is suggested. >

Outliers are difficult to handle because some of them can be measurement errors, while others may represent phenomena of interest, something “significant” from the viewpoint of the application domain. Statistical methods for managing outliers do not distinguish between these two possibilities. In our previous work, we suggested a method for distinguishing these two possibilities by modelling “real measurements” — how measurements should be distributed in a domain of interest. In this paper, we make this distinction by modelling measurement errors instead. The proposed method is better suited to those applications where it is difficult to obtain relevant knowledge about real measurements. The test data collected from a recent glaucoma case finding study in a general practice are used to evaluate the method.

A resonant Schottky pickup was built into the experimental storage ring at GSI Darmstadt in 2010 and a similar one in the CSRe storage ring at IMP Lanzhou in 2011. Single-ion sensitivity was achieved at 400 MeV u−1. The pickup has also been used in many storage ring experiments ever since. A brief description of the pickup and its application in single-ion lifetime spectroscopy is provided in this work.

The Computer Controlled Video Perimetry (CCVP) is a computer screening test for detecting visual function loss caused by onchocerciasis, glaucoma, etc. Installed on portable computers, the CCVP has been shown to be high acceptability in field community investigation. However, it is regarded to be difficult in obtaining reliable results from portable computer screening tests because of human behavioural variants and the lack of standard testing environment. In this paper, we propose an architecture for implementing a more reliable CCVP system. In particular, a self-organising neural network is applied to manage measurement noise caused by behavioural factors. A control unit is introduced to manage the overall behaviour of the system. The integrated test system has been used to screen optic nerve disease in onchocercal communities of rural Nigeria and the experimental results obtained from a large number of test records are very encouraging: reliable results from volatile test environments may be obtained using the proposed method.

Diagnosis of visual function losses in glaucomatous patients depends to a large extent on the analysis of the data collected from corresponding psychophysical tests. One of the main difficulties in obtaining reliable data from patients in these tests is the measurement noise caused by the learning effect, inattention, failure of fixation, fatigue etc. Using Kohonen's self-organising feature map, we have developed a computational method to distinguish between the noise and true measurement and to provide an instant assessment of reliability of the computer-based visual function test. In particular we have experimented with 270 test records from glaucoma patients and glaucoma suspects and found that this method provides a satisfactory way of locating and rejecting noise in the test data, an improvement over conventional statistical methods. This method can also provide doctors with a clear view of the patient's behaviour during the test, thus assisting in their diagnostic decision making process.

An experimental end-to-end anastomosis of the common femoral artery was performed in 45 adult Wistar rats. The vessel wall condition was assessed at 10 min, 3 days, 1, 2, 4, and 8 weeks following surgery by scanning and transmission electron microscopy. The microsurgical procedure inflicts extensive trauma in all layers of the arterial wall, with a desendothelialization largely surpassing the surgical field. Reendothelialization was completed at 2 weeks. Apparently, and as compared to less damaging vessel wall manipulations, such deep medial and wide endothelial lesions do not retard vessel wall healing to normal functionality. Moreover, the formation of primary atherogenic structures by smooth muscle cell migration to the intima seems restricted.