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Light transmission at the Au/air interface was measured for wedge-shaped Au film samples. Light refraction continuously changing its sign from positive to negative at the Au/air interface in the spectrum range of 470–700 nm was observed with a zero refraction occurred at about 525 nm. The results indicate that the effective refraction index n e of samples are not correlated with wedge angles, implying that n e can be considered an intrinsic characteristic of the metal material. The positive and negative refractions observed in the experiment can be attributed to the dispersive feature of the dielectric function of Au with qualitative explanation according to the mechanisms of electron transition and the boundary conditions restricted at the interface. [ABSTRACT FROM AUTHOR]

• Indium nanoparticles with different size distributions are studied by ellipsometry. • The optical properties are obtained by the multi-oscillator Lorentz model. • Resonances in large and small particles are modeled by two oscillators. • Delocalization of electrons is modeled by an oscillator with a low energy. Indium has attracted widespread attention due to its compelling optical properties for promising applications in plasmonics. In this work, we employ spectroscopic ellipsometry to investigate the optical properties of indium nanoparticle films with different size distributions fabricated by using electron beam evaporation. We propose a method to distinguish optical responses arising from electron behaviors in different structures by fitting the multi-oscillator Drude-Lorentz dispersion model. For the particle films with bimodal size distributions, localized surface plasmon resonances arising from electron oscillations in both large and small particles are modeled by applying two oscillators. The formation of densified structures, resulting from contacts of adjacent particles, is revealed by adding an oscillator with a center energy close to zero. The validity of the multi-oscillator model is qualitatively verified by using scanning electron microscopy and atomic force microscopy. Reflectance spectra justify quantitively the proposed model. This study is beneficial for the applications of nanostructured indium films in advanced plasmonic devices. The ellipsometric modeling on indium particle films provides a means of distinguishing the contributions of diverse electron behaviors to optical responses in complex nanostructures. [ABSTRACT FROM AUTHOR]

• Brief review of the history of SE research and development in China. • Exploration of future challenges to tackle by the SE community. • The new configurations of DRC-MMIE and high speed SE system without mechanic moving parts in parallel mode are presented. Following the fast and advanced development of technologies worldwide in the early 1970s, especially focusing on industry and academic applications, research on spectroscopic ellipsometry (SE) has been significantly performed in many universities and institutes in China, which is a typical developing country. Through strong international cooperation, various SE configurations have been proposed and achieved in real and practical applications. Improvements in SE instrumentation have been stimulated and approached in the broad spectral region, providing powerful tools to study the optical properties of materials and micro/nanostructures under variable experimental conditions. Thus, a brief review of the historical research and development of SE in China is presented, and future challenges are discussed. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 nanocrystal/nanotube hybrids were presented and prepared by incubating non-prefabricated TiO2 nanocrystals in anodized TiO2 nanotubes. TiO2 nanocrystals were incubated inside the nanotubes with tuning size and aggregation morphology by means of a block copolymer-assisted evaporation induced self-assembly (EISA) process. Compared with that of the bare TiO2 nanotubes, a ∼44% increase of the concentration of dye absorbed in the TiO2 nano-hybrids was estimated from the absorption spectra. The nanostructure hybrids increased internal surface area, and were used to optimize TiO2-based photo-electrochemical conversion. The contrast of light conversion efficiency revealed an improvement from 0.75% to 1.87% when the TiO2 nano-hybrids were used as photoanodes instead of the bare nanotube arrays. [Copyright &y& Elsevier]

An effective method for determining the optical constants of TaO thin films deposited on crystal silicon (c-Si) using spectroscopic ellipsometry (SE) measurement with a two-film model (ambient-oxide-interlayer-substrate) was presented. TaO thin films with thickness range of 1-400 nm have been prepared by the electron beam evaporation (EBE) method. We find that the refractive indices of TaO ultrathin films less than 40 nm drop with the decreasing thickness, while the other ones are close to those of bulk TaO. This phenomenon was due to the existence of an interfacial oxide region and the surface roughness of the film, which was confirmed by the measurement of atomic force microscopy (AFM). Optical properties of ultrathin film varying with the thickness are useful for the design and manufacture of nano-scaled thin-film devices. [ABSTRACT FROM AUTHOR]

The Ag:Bi2O3 composite samples with nano-sized Ag particles embedded in the bismuth oxide matrices have been prepared by using the co-sputtering method. The concentration of Ag particles was varied from 13.2 to 59.3% in the films as determined by Rutherford back-scattering method. The surface plasma resonance peaks shown in the optical absorption spectra are shifted to the long wavelength with increasing Ag concentration because of the increasing electromagnetic interaction between metal particles and the Mie multiple scattering effect. The complex refractive index data obtained by the ellipsometric method are qualitatively in agreement with the simulated ones based on the effective mass approximation model that is suitable for the structure of composite films as revealed by the transmission electron microscope image picture. [Copyright &y& Elsevier]

The 2D magnet Fe 3 GaTe 2 has received considerable attention for its high Curie temperature ( T C ), robust intrinsic ferromagnetism, and significant perpendicular magnetic anisotropy (PMA). In this study, the dynamic magnetic properties of Fe 3 GaTe 2 are systematically investigated using an all-optical pump-probe technique. We find that the spin precession frequency ( f ) is as high as 351.2 GHz at T = 10 K under a field of H = 70 kOe. However, it decreases to 242.8 GHz at 300 K, mainly due to the reduced effective PMA field ( H keff ). The Gilbert damping factor (α) is modest, which increases from 0.039 (10 K) to 0.075 (300 K) owing to the enhanced scattering rate. Interestingly, when Fe 3 GaTe 2 is coupled with 2 nm of Co, the H keff , f , and α just decrease slightly, highlighting the dominant influence of Fe 3 GaTe 2 . These findings substantially deepen our understanding of Fe 3 GaTe 2 , promoting the development of spintronic devices based on advanced 2D magnetic materials.

Broader spectra, lower reflectivity and higher reliability are the performance requirements for broadband antireflective (BBAR) films. In this work, a BBAR film structure was proposed, which maintains extremely low reflectivity, ultra-wide spectra, low polarization sensitivity and practical reliability. The BBAR film consists of a dense multilayer interference stack on the bottom and a nano-grass-like alumina (NGLA) layer with a gradient low refractive index distribution on the top. The film was deposited by atomic layer deposition, while the NGLA layer was formed by means of a hot water bath on Al 2 O 3 layer. The top NGLA layer has extremely high porosity and ultra-low refractive index, along with extremely fragile structure. To surmount the fragility of NGLA layer, a sub-nano layer of SiO 2 was grown by atomic layer deposition to solidify its structure and also to adjust the refractive index with different thicknesses of SiO 2 . Finally, in the wide wavelength range of 400-1100 nm, the average transmittance of the double-sided coated fused quartz reaches 99.2%. The absorption, light scattering, reliability and polarization characteristics of BBAR films were investigated. An optimized BBAR film with low polarization-sensitivity and improved reliability was realized, which should be potentially promising for application in optical systems.

It is of great technological importance in the field of plasmonic color generation to establish and understand the relationship between optical responses and the reflectance of metallic nanoparticles. Previously, a series of indium nanoparticle ensembles were fabricated using electron beam evaporation and inspected using spectroscopic ellipsometry (SE). The multi-oscillator Lorentz-Drude model demonstrated the optical responses of indium nanoparticles with different sizes and size distributions. The reflectance spectra and colorimetry characteristics of indium nanoparticles with unimodal and bimodal size distributions were interpreted based on the SE analysis. The trends of reflectance spectra were explained by the transfer matrix method. The effects of optical constants n and k of indium on the reflectance were demonstrated by mapping the reflectance contour lines on the n - k plane. Using oscillator decomposition, the influence of different electron behaviors in various indium structures on the reflectance spectra was revealed intuitively. The contribution of each oscillator on the colorimetry characteristics, including hue, lightness and saturation, were determined and discussed from the reflectance spectral analysis.

Background: Positron emission tomography (PET) imaging is a non-invasive method to visualize and quantify the tumor microenvironment. This study aimed to explore the feasibility of 18 F-AIF-NOTA-E[PEG 4 -c(RGDfk)] 2 (denoted as 18 F-RGD) PET quantitative parameters to distinguish the angiogenesis in colorectal cancer (CRC) mice which has different metastatic potential., Methods: Twenty LoVo and twenty LS174T of CRC liver metastases animal models were established by implantation of human CRC cell lines via intrasplenic injection. Radiotracer-based micro-PET imaging of animal model was performed and the uptake of 18 F-RGD tracer in the tumor tissues was quantified as tumor-to-liver maximum or mean standardized uptake value (SUVmax or SUVmean) ratio. Pearson correlation was used to analyze the relationship between radioactive parameters and tumor markers., Results: The SUVmax and SUVmean ratios of LoVo model were significantly higher than those of LS174T in both liver metastasis and primary tumor lesions (P < 0.05). A significant difference was observed in both vascular endothelial growth factor (VEGF) and Ki67 expressions between LoVo and LS174T primary tumors (P < 0.05). The tumor-to-liver SUVmax or SUVmean ratio of 18 F-RGD showed a moderate correlation with VEGF expression (r = 0.5700, P = 0.001 and r = 0.6657, P < 0.001, respectively), but the SUVmean ration showed a weak correlation with Ki67 expression (r = 0.3706, P < 0.05). The areas under the receiver operating characteristic (ROC) curves of 18 F-RGD SUVmean ratio, SUVmax ratio for differentiating LoVo from LS174T tumor were 0.801 and 0.759, respectively., Conclusions: The tumor-to-liver SUVmean ratio of 18 F-RGD was a promising image parameter for the process of monitoring tumor angiogenesis in CRC xenograft mice model., (Copyright © 2021 First Affiliated Hospital, Zhejiang University School of Medicine in China. Published by Elsevier B.V. All rights reserved.)

Monolayer MoS2 is a direct bandgap semiconductor which is believed to be one of the most promising candidates for optoelectronic devices. Chemical vapor deposition (CVD) is the most popular method to synthesize monolayer MoS2 with a large area. However, many defects are always found in monolayer MoS2 grown by CVD, such as sulfur vacancies, which severely degrade the performance of devices. This work demonstrates a concise and effective method for direct growth of high quality monolayer MoS2 by using SiO2/Si substrates pretreated with sulfur vapor. The MoS2 monolayer obtained using this method shows about 20 times PL intensity enhancement and a much narrower PL peak width than that grown on untreated substrates. Detailed characterization studies reveal that MoS2 grown on sulfur vapor pretreated SiO2/Si substrates has a much lower density of sulfur vacancies. The synthesis of monolayer MoS2 with high optical quality and low defect concentration is critical for both fundamental physics studies and potential practical device applications in the atomically thin limit.

Objective: To observe the effect of acupuncture plus moxibustion on the synaptic ultrastructure and expression of synaptic skeleton related proteins in the prefrontal cortex (PFC) of heroin re-addicted rats, so as to reveal its mechanisms underlying improvement of heroin addiction., Methods: Twenty-four Wister rats (half male and half female) were randomly divi-ded into normal control, model and acupuncture groups ( n ＝8 in each group). The heroin re-addicted model was established by muscular injection of heroin into the hind limbs for 8 days (incremental 0.8-3.6 mg, once daily for 6 days, and twice daily for 2 days), followed by conventional breeding for 5 days (detoxification), the procedure (addition－detoxification) was repeated 3 cycles. For rats of the acupuncture group, "Baihui" (GV20) was needled with filiform needles which were retained for 30 min, and moxibustion was then applied to bilateral "Shenshu" (BL23) for 30 min. The treatment was conducted once daily during the deto-xification. On the 39 th day of experiment, the bilateral prefrontal cortex tissues were sampled for examining the ultrastructure by using transmission electron microscope (TEM) after fixative solution immersion and for determining the expression of genes and proteins of activity-regulated cytoskeleton-associated protein (Arc), microtubule-asso-ciated protein-2 (MAP-2) and microtubule-associated protein Tau (Tau) with quantitative real-time PCR and Western blot, respectively., Results: After modeling, the expression levels of Arc mRNA and protein were significantly up-regulated, and those of MAP-2 and Tau mRNA and proteins ob-viously down-regulated in the model group relevant to the normal control group ( P <0.05). Following the intervention, the up-regulated Arc protein and mRNA and the down-regulated MAP-2 and Tau were obviously reversed relevant to the model group ( P <0.05). Outcomes of TEM showed unclear pre- and post-membranes of the synapses, narrowing of the synaptic gap and non-uniform of the density of the thickened dense plaque after modeling, which was relatively milder in the acupuncture group., Conclusion: Acupuncture plus moxibustion can improve changes of synaptic ultrastructure in heroin re-addicted rats, which may be related to their effect in regulating the expression of some synaptic skeleton proteins and genes.

Background: Positron emission tomography (PET) imaging is a non-invasive functional imaging method used to reflect tumor spatial information, and to provide biological characteristics of tumor progression. The aim of this study was to focus on the application of 18 F-fluoromisonidazole (FMISO) PET quantitative parameter of maximum standardized uptake value (SUVmax) ratio to detect the liver metastatic potential of human colorectal cancer (CRC) in mice., Methods: Colorectal liver metastases (CRLM) xenograft models were established by injecting tumor cells (LoVo, HT29 and HCT116) into spleen of mice, tumor-bearing xenograft models were established by subcutaneously injecting tumor cells in the right left flank of mice. Wound healing assays were performed to examine the ability of cell migration in vitro. 18 F-FMISO uptake in CRC cell lines was measured by cellular uptake assay. 18 F-FMISO-based micro-PET imaging of CRLM and tumor-bearing mice was performed and quantified by tumor-to-liver SUVmax ratio. The correlation between the 18 F-FMISO SUVmax ratio, liver metastases number, hypoxia-induced factor 1α (HIF-1α) and serum starvation-induced glucose transporter 1 (GLUT-1) was evaluated using Pearson correlation analysis., Results: Compared with HT29 and HCT116, LoVo-CRLM mice had significantly higher liver metastases ratio and shorter median survival time. LoVo cells exhibited stronger migration capacity and higher radiotracer uptake compared with HT29 and HCT116 in in vitro. Moreover, 18 F-FMISO SUVmax ratio was significantly higher in both LoVo-CRLM model and LoVo-bearing tumor model compared to models established using HT29 and HCT116. In addition, Pearson correlation analysis revealed a significant correlation between 18 F-FMISO SUVmax ratio of CRLM mice and number of liver metastases larger than 0.5 cm, as well as between 18 F-FMISO SUVmax ratio and HIF-1α or GLUT-1 expression in tumor-bearing tissues., Conclusions: 18 F-FMISO parameter of SUVmax ratio may provide useful tumor biological information in mice with CRLM, thus allowing for better prediction of CRLM and yielding useful radioactive markers for predicting liver metastasis potential in CRC., (Copyright © 2019 First Affiliated Hospital, Zhejiang University School of Medicine in China. Published by Elsevier B.V. All rights reserved.)

MgxZn1-xO (ZMO) thin films with tunable Mg content were deposited by atomic layer deposition (ALD) on silicon substrates at 190 °C. The elemental and structural properties were acquired by X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy and X-ray diffraction. Spectroscopic ellipsometry measurements were performed to reveal the evolution of the dielectric functions and critical points in the ZMO thin films by point-by-point fit in the photon energy range of 1.2-6.0 eV. The dependence of the dielectric functions on doping content is clearly demonstrated and physically explained. The critical point energies and the types of interband optical transitions were extracted from standard lineshape analysis of the second derivatives of the dielectric functions. The critical point features were discussed in terms of band structure modification and structural homogeneity arisen by introducing the Mg dopant into the films. Controlling these transitions by changing the doping content will be of practical significance in emerging ZMO-based thin-film photonic and optoelectronic devices.

Oxidative stress is known to be associated with various age-related diseases. D-galactose (D-gal) has been considered a senescent model which induces oxidative stress response resulting in memory dysfunction. Pyrroloquinoline quinone (PQQ) is a redox cofactor which is found in various foods. In our previous study, we found that PQQ may be converted into a derivative by binding with amino acid, which is beneficial to several pathological processes. In this study, we found a beneficial glutamate mixture which may diminish neurotoxicity by oxidative stress in D-gal induced mouse. Our results showed that PQQ may influence the generation of proinflammatory mediators, including cytokines and prostaglandins during aging process. D-gal-induced mouse showed increased MDA and ROS levels, and decreased T-AOC activities in the hippocampus, these changes were reversed by PQQ supplementation. Furthermore, PQQ statistically enhanced Superoxide Dismutase SOD2 mRNA expression. PQQ could ameliorate the memory deficits and neurotoxicity induced by D-gal via binding with excess glutamate, which provide a link between glutamate-mediated neurotoxicity, inflammation and oxidative stress. In addition, PQQ reduced the up-regulated expression of p-Akt by D-gal and maintained the activity of GSK-3β, resulting in a down-regulation of p-Tau level in hippocampus. PQQ modulated memory ability partly via Akt/GSK-3β pathway.

The optical properties of aluminum-doped zinc oxide (AZO) thin films were calculated rapidly and accurately by point-by-point analysis from spectroscopic ellipsometry (SE) data. It was demonstrated that there were two different physical mechanisms, i.e., the interfacial effect and crystallinity, for the thickness-dependent permittivity in the visible and infrared regions. In addition, there was a blue shift for the effective plasma frequency of AZO when the thickness increased, and the effective plasma frequency did not exist for AZO ultrathin films (< 25 nm) in the infrared region, which demonstrated that AZO ultrathin films could not be used as a negative index metamaterial. Based on detailed permittivity research, we designed a near-perfect absorber at 2-5 μm by etching AZO-ZnO alternative layers. The alternative layers matched the phase of reflected light, and the void cylinder arrays extended the high absorption range. Moreover, the AZO absorber demonstrated feasibility and applicability on different substrates.

Titanium dioxide (TiO 2 ) ultrathin films with different thicknesses below 20 nm were grown by atomic layer deposition (ALD) on silicon substrates at 300 °C. Spectroscopic ellipsometry (SE) measurements were operated to investigate the effect of thickness on the optical properties of ultrathin films in the spectra range from 200 to 1000 nm with Forouhi-Bloomer (F-B) dispersion relation. It has been found that the refractive index and extinction coefficient of the investigated TiO 2 ultrathin film increase while the band gap of TiO 2 ultrathin film decreases monotonically with an increase in film thickness. Furthermore, with the purpose of studying the temperature dependence of optical properties of TiO 2 ultrathin film, the samples were annealed at temperature from 400 to 900 °C in N 2 atmosphere. The crystalline structure of deposited and annealed films was deduced by SE and supported by X-ray diffraction (XRD). It was revealed that the anatase TiO 2 film started to transform into rutile phase when the annealing temperature was up to 800 °C. In this paper, a constructive and effective method of monitoring the phase transition in ultrathin films by SE has been proposed when the phase transition is not so obvious analyzed by XRD.

This report mainly focuses on the investigation of morphological, optical, and electrical properties of Al 2 O 3 /ZnO nanolaminates regulated by varying bilayer thicknesses. The growth mechanism of nanolaminates based on atomic layer deposition and Al penetration into ZnO layer are proposed. The surface roughness of Al 2 O 3 /ZnO nanolaminates can be controlled due to the smooth effect of interposed Al 2 O 3 layers. The thickness, optical constants, and bandgap information of nanolaminates have been investigated by spectroscopic ellipsometry measurement. The band gap and absorption edge have a blue shift with decreasing the bilayer thickness on account of the Burstein-Moss effect, the quantum confinement effect and the characteristic evolution of nanolaminates. Also, the carrier concentrations and resistivities are found to be modified considerably among various bilayer thicknesses. The modulations of these properties are vital for Al 2 O 3 /ZnO nanolaminates to be used as transparent conductor and high resistance layer in optoelectronic applications.

Objectives: To evaluate regulation of the endoplasmic reticulum stress (ERS) response by acupuncture and to investigate its neuroprotective effect on brain injury caused by heroin addiction., Methods: A total of 48 male Sprague-Dawley rats were randomly divided into a healthy control group (Control), an untreated heroin exposed group (Heroin) and a heroin exposed group receiving electroacupuncture (EA) treatment at GV14 and GV20 (Heroin+acupuncture) with n=16 rats per group. A rat model of heroin addiction was established by intramuscular injection of incremental doses of heroin for 8 consecutive days. A rat model of heroin relapse was established according to the exposure (addiction) → detoxification method. Apoptotic changes in nerve cells in the hippocampus and ventral tegmental area (VTA) were evaluated in each group of rats using terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay. PERK, eIF2a, CHOP, IRE1 and JNK gene expression and protein expression were measured using quantitative real-time PCR (RT-qPCR) assay and immunohistochemical assay, respectively., Results: The total number of positive nerve cells in the hippocampus and VTA was significantly lower in the Heroin+acupuncture group than in the Heroin group (p<0.01). Compared with the Heroin group, mRNA and protein expression of PERK, eIF2a, CHOP, IRE1 and JNK in the hippocampus and VTA were significantly downregulated in the Heroin+acupuncture group (p<0.05)., Conclusion: The acupuncture-regulated ERS response appears to mediate the neuroprotective effect of acupuncture in heroin-addicted rats with brain injury. Inhibition of CHOP and JNK upregulation and reduction of nerve cell apoptosis may be the main mechanisms underlying the effects of acupuncture on heroin addiction-induced brain injury., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Bismuth selenide (Bi 2 Se 3 ), with a wide bulk band gap and single massless Dirac cone at the surface, is a promising three-dimensional topological insulator. Bi 2 Se 3 possesses gapless surface states and an insulator-like bulk band gap as a new type of quantum matter. Different Bi 2 Se 3 nanostructures were prepared using electron beam evaporation with high production efficiency. Structural investigations by energy-dispersive X-ray analysis, scanning electron microscopy, and X-ray diffraction revealed the sample stoichiometries and the structural transition mechanism from nanocrystals to nanoflakes. The optical properties systematically probed and analyzed by spectroscopic ellipsometry showed strong dependence on the nanostructures and were also predicted to have structure-modifiable technological prospects. The optical parameters, plasma frequencies, scattering rates of the free electrons, and optical band gaps were related to the topological properties of the Bi 2 Se 3 nanostructures via light-matter interactions, offering new opportunities and approaches for studies on topological insulators and spintronics. The high-quality Bi 2 Se 3 nanostructures provide advantages in exploring novel physics and exploiting prospective applications.

Centimeter-scale WS 2 ultrathin films were synthesized on sapphire substrates, and they showed highly oriented crystallographic growth along the c axis. Afterwards, the as-grown samples were systematically characterized using various detection methods. Reliable values of the roughness layer thickness and the film thickness were extracted using both atomic force microscopy (AFM) and spectroscopic ellipsometry (SE), and identified using Raman spectroscopy as well. The expansion and tensile strain along the [001] direction were discovered using X-ray diffraction (XRD) measurements. Accurate dielectric functions of WS 2 films were derived from the point-by-point fitting results. The critical points (CPs) of WS 2 , which have not been reported so far, are precisely extracted from the standard critical point (SCP) model. Their origins are uniquely assigned to different interband electronic transitions in the Brillouin zone, including some novel optical structures above 3 eV, which were not investigated in earlier studies. In this work, it is found that dielectric functions are thickness-dependent, while CPs have an opposite nature, and their intrinsic mechanisms are revealed. The as-obtained results can be expected to help people develop more extensive applications of WS 2 .

In this work, 4-layered SiO 2 /Bi 2 Te 3 /SiO 2 /Cu film structures were designed and fabricated and the optical properties investigated in the wavelength region of 250-1200 nm for their promising applications for direct solar-thermal-electric conversion. A typical 4-layered film sample with the structure SiO 2 (66.6 nm)/Bi 2 Te 3 (7.0 nm)/SiO 2 (67.0 nm)/Cu (>100.0 nm) was deposited on a Si or K9-glass substrate by magnetron sputtering. The experimental results agree well with the simulated ones showing an average optical absorption of 96.5%, except in the shorter wavelength region, 250-500 nm, which demonstrates the superior absorption property of the 4-layered film due to the randomly rough surface of the Cu layer resulting from the higher deposition power. The high reflectance of the film structure in the long wavelength region of 2-20 μm will result in a low thermal emittance, 0.064 at 600 K. The simpler 4-layered structure with the thermoelectric Bi 2 Te 3 used as the absorption layer may provide a straightforward way to obtain solar-thermal-electric conversion more efficiently through future study.

The tuning of structural, optical, and electrical properties of Al-doped ZnO films deposited by atomic layer deposition technique is reported in this work. With the increasing Al doping level, the evolution from (002) to (100) diffraction peaks indicates the change in growth mode of ZnO films. Spectroscopic ellipsometry has been applied to study the thickness, optical constants, and band gap of AZO films. Due to the increasing carrier concentration after Al doping, a blue shift of band gap and absorption edge can be observed, which can be interpreted by Burstein-Moss effect. The carrier concentration and resistivity are found to vary significantly among different doping concentration, and the optimum value is also discussed. The modulations and improvements of properties are important for Al-doped ZnO films to apply as transparent conductor in various applications.

Purpose: The benefit of adjuvant chemotherapy (AC) in locoregionally advanced nasopharyngeal carcinoma (NPC) is controversial. This study compared concurrent chemoradiotherapy plus AC (CCRT/AC) with CCRT., Methods: Pair-matched analysis based on eight clinicopathological features of 244 patients treated with platinum-based CCRT/AC or CCRT alone was performed. Survival outcomes were assessed using the Kaplan-Meier method and log-rank test. Toxicities and response rates were compared using Fisher's exact test., Results: Four-year overall survival, progression-free survival, distant failure-free survival, and locoregional failure-free survival were 72 %, 61 %, 71 %, and 81 %, respectively, for the CCRT arm, compared to 74 % (hazard ratio, HR 0.89; 95 % confidence interval, CI 0.64-1.23; P = 0.474), 62 % (HR 0.91, 95 % CI 0.68-1.20, P = 0.489), 73 % (HR 0.84, 95 % CI 0.59-1.18, P = 0.316), and 84 % (HR 0.84, 95 % CI 0.52-1.24, P = 0.323), respectively, for the CCRT/AC arm. Cox multivariate regression analysis demonstrated AC was not an independent prognostic factor. Overall, there was a higher incidence of grade 3-4 toxicities in the CCRT/AC arm. The most common grade 3-4 adverse events in the CCRT/AC arm were vomiting (27 %), nausea (43 %), leukopenia/neutropenia (23 %), thrombocytopenia (8.8 %), and anemia (6.2 %)., Conclusion: Addition of AC to CCRT increased toxicities but did not improve survival in locoregionally advanced NPC.

The aluminum oxide (Al2O3) thin films with various thicknesses under 50 nm were deposited by atomic layer deposition (ALD) on silicon substrate. The surface topography investigated by atomic force microscopy (AFM) revealed that the samples were smooth and crack-free. The ellipsometric spectra of Al2O3 thin films were measured and analyzed before and after annealing in nitrogen condition in the wavelength range from 250 to 1,000 nm, respectively. The refractive index of Al2O3 thin films was described by Cauchy model and the ellipsometric spectra data were fitted to a five-medium model consisting of Si substrate/SiO2 layer/Al2O3 layer/surface roughness/air ambient structure. It is found that the refractive index of Al2O3 thin films decrease with increasing film thickness and the changing trend revised after annealing. The phenomenon is believed to arise from the mechanical stress in ALD-Al2O3 thin films. A thickness transition is also found by transmission electron microscopy (TEM) and SE after 900°C annealing.

The BiFeO3 (BFO) thin film was deposited by pulsed-laser deposition on SrRuO3 (SRO)-buffered (111) SrTiO3 (STO) substrate. X-ray diffraction pattern reveals a well-grown epitaxial BFO thin film. Atomic force microscopy study indicates that the BFO film is rather dense with a smooth surface. The ellipsometric spectra of the STO substrate, the SRO buffer layer, and the BFO thin film were measured, respectively, in the photon energy range 1.55 to 5.40 eV. Following the dielectric functions of STO and SRO, the ones of BFO described by the Lorentz model are received by fitting the spectra data to a five-medium optical model consisting of a semi-infinite STO substrate/SRO layer/BFO film/surface roughness/air ambient structure. The thickness and the optical constants of the BFO film are obtained. Then a direct bandgap is calculated at 2.68 eV, which is believed to be influenced by near-bandgap transitions. Compared to BFO films on other substrates, the dependence of the bandgap for the BFO thin film on in-plane compressive strain from epitaxial structure is received. Moreover, the bandgap and the transition revealed by the Lorentz model also provide a ground for the assessment of the bandgap for BFO single crystals.

The microstructure and fracture morphology of carbon coatings were investigated by means of Raman spectrometer and scanning electron microscopy (SEM), which were prepared by chemical vapor deposition (CVD) on the surface of SiC fiber with C2 H2 + H2 and C2 H2 +C3 H8 + Ar as the reactants. The results show that the spectra of the carbon coating contain characteristic D, D" and G peaks around 1 350, 1 400-1 500 and 1 600 cm(-1) respectively, indicating a disordered-graphite structure with a small amount of amorphous carbon. The size of microcrystallite increased with the increase in temperature, and the degree of order, together with the uniformity in the carbon coating was improved simultaneously. It was observed on the fracture surface that coatings prepared by C2 H2 + H2 are flat and dense, whereas those prepared by C2 H2 + C3 H8 + Ar exhibit a flexural lamellar structure, which should be attributed to the relatively low degree of order and the non-uniformity in the microstructure.

The effect of acupuncture on substance withdrawl syndromes and craving relapse prevention of the recent 10 years were reviewed as well as its mechanism. The therapeutic effect and the possible mechanism were analyzed on the basis. From the three aspects of anti protracted abstinence symptoms, craving relapse prevention and mechanism of acupuncture, the development tendency and the prospect of application on drug withdrawl with acupuncture were expected. And it is proposed that clinical observation of acupuncture intervention on craving should be developed, the mechanism of acupuncture impact on cognitive behavior, blocking study and memory processing related to drug addiction should be explored, so as to further give play to the advantages of acupuncture on anti-drug addiction.

The effectiveness of Resovist-labeled bone marrow stem cells (BMSCs) was evaluated in vivo following their cerebral transplantation in a model of Parkinson's disease (PD) in rats using MRI, and the MRI findings were further compared with the behavior and histopathological manifestations of these rats. Forty PD rats were randomly assigned into five groups according to the cell doses injected into the rat brain site: control group (normal saline injection) and groups injected with 1 × 10(5), 1.5 × 10(5), 2 × 10(5), and 2.5 × 10(5) BMSCs. Gradient echo T2-weighted images were obtained immediately after cell transplantation and repeatedly taken 1, 4, 8, and 12 week(s) after cell transplantation. The rotational behavior of the animals was observed before and 1, 4, and 8 week(s) after transplantation. The rats were killed after the last MRI scanning, the brain tissues were analyzed by histopathology techniques, and RNAs were extracted for the expression analysis of selected genes using RT-PCR. One week following cell transplantation, all injected sites showed well-defined hypointense areas on MR images, with the most significant effect observed in rats injected with 2 × 10(5) BMSCs. These MR findings in PD rats lasted up to 12 weeks. The effectiveness of BMSC transplantation revealed by MRI was well confirmed by the behavioral and histopathological observations as well as indirectly supported by gene expression analyses. With the use of SPIO labeling, MRI techniques provided a dynamic evaluation of the spatial and temporal changes following cell transplantation and allowed the association analysis among the imaging, functions, and gene expression analysis in rats. These data also suggest the therapeutic potential of transplanted BMSCs. It is reasonable to speculate that the use of MRI in in vivo evaluation of the effect and fate of transplanted cells in various disease models will be beneficial to developing new strategies of cell-based gene therapy.

Objective: To observe the effect of acupuncture and moxibustion on the conditional position preference (CPP) and prefrontal cortical ultrastructure in heroin re-addicted rats., Methods: Thirty-two Wistar rats were randomly divided into normal, model, medication and acu-moxibustion (acu-moxi) groups, with 8 cases in each. Re-addiction model was established by repeated intramuscular injection of heroin into the hindlimbs. Rats of medication group were treated with intragastric administration of Methadone during detoxification. For rats in acu-moxi group, acupuncture needle was inserted into "Baihui" (GV 20) and moxibustion treatment was used to bilateral "Shenshu" (BL 23) for 30 min during detoxification. Rats in normal group were given with intramuscular injection of normal saline during addiction. CPP tests were conducted once daily in a spatial place preference box for 8 days. On the 39th day of the experiment, the rats under anesthesia were killed for sampling the prefrontal cortex (PFC) tissue on an ice plate, then, the ultrastructure of the neurons was observed by using a transmission electron microscope., Results: After modeling, the rats' staying duration in the dark-box was shortened obviously (P < 0. 1). After the treatment, the staying duration in dark-box in acu-moxi group was significantly longer than that in model and medication groups (P < 0.01). Compared with normal control group, electron-microscopic results indicated that in PFC tissues of model and medication groups, vacuoles and edema of cytoplasm at different degrees, enlargement of the rough endoplasmic reticulum (REPR), vacuoles or disappearance of mitochondria, reduction of ribosome in number, and widening of the nuclear intermembrance interstice were seen. While in acu-moxi group, the number of mitochondria and ribosome increased slightly, the mitochondrial cristae was clear, the number of REPR increased relatively but dilated slightly, and the intermembrance space was basically normal., Conclusion: Acu-moxibustion can improve heroin re-addicted rats' conditional position preference and has a protection effect on the cerebral cortical neurons. disappearance of mitochondria, reduction of ribosome in number, and widening of the nuclear intermembrance interstice were seen. While in acu-moxi group, the number of mitochondria and ribosome increased slightly, the mitochondrial cristae was clear, the number of REPR increased relatively but dilated slightly, and the intermembrance space was basically normal., Conclusion: Acu-moxibustion can improve heroin re-addicted rats' conditional position preference and has a protection effect on the cerebral cortical neurons.

Objective: To explore the underlying mechanism of electroacupuncture (EA) in relieving morphine withdrawal syndrome in rats., Methods: Forty SD rats were randomly divided into normal control group, model group 1, model group 2 and EA group. Morphine withdrawal syndrome model was established by muscular injection of morphine (5 mg/kg on the 1st day, progressively increasing everyday till 100 mg/kg on the 20th day) in the hind limbs. Then, rats of model group 1 were anesthetized (10% chloraldurat) to be killed on the 21st day, and those of model group 2 killed on the 27th day. EA (2/100 Hz, 2-4 mA) was applied to bilateral "Zusanli" (ST 36) for 30 mm, once a day for 7 days. The rat's thymus was removed (after anesthesia), cut into sections (4 pm) and stained with immunohistochemical method for displaying the expression of apoptotic promoters Bax, Fas, Fas Ligand (FasL) as well as anti-apoptotic peptide Bcl-2., Results: Compared with normal group, Bcl-2 immunoreaction (IR)-positive cell number of model group 1 and group 2 decreased significantly while Sax, Fas and FasLIR-positive cell number and Bax/Bcl-2 in two model groups increased considerably (P < 0.01). In comparison with model group 2, Bcl-2 IR-positive cell number of model group 1 decreased significantly (P < 0.05), Bax, Fas and FasL IR-positive cell number and Bax/Bcl-2 of model group 1 were significantly higher (P < 0.01, fl. 05). After EA, in comparison with model group 2, Fas and FasL IR-positive cell number and Bax/Bcl-2 decreased significantly (P < 0.01, 0.05), and Bcl-2 IR-positive cell number increased markedly in EA group (P < 0.05); in comparison with model group 1, Bcl-2 IR-positive cell number increased significantly (P < 0.01), while Bax, Fas and FasL IR-positive cell number and Bax/Bcl-2 decreased evidently in EA group (P < 0.01)., Conclusion: EA at "Zusanli" (ST 36) can inhibit morphine-induced downregulation of Bcl-2 and upregulation of Fas and FasL expression, which may contribute to its effect in resisting thymus apoptosis in morphine withdrawal rats.

Aim: To study the effect of recombinant hirudin (rH) on tPA-induced fibrinolysis and the possible mechanism of its action., Methods: The effect of rH on thrombin-fibrin complex (Th-Fn) was detected by 99mTc labeled rH. In the in vitro clot lysis, tPA as plasminogen activator, and recalcified plasma as plasminogen resource were used to study the influence of rH on fibrinolysis by detecting TAFIa, D-Dimer and FXIII., Results: In a canine model of femoral artery thrombosis, a clear radioactivity strip was imaged in 30 - 60 min on a part image, and the femoral vein thrombosis developed at 30 min. rH efficiently inhibited clot regeneration. Addition of TM could inhibit clot lysis obviously, and CPI could shorten the delay of clot lysis which due to TAFIa. There was a dose-dependent relationship with TM concentration and TAFI activation. FXIII activation was inhibited by low concentration of rH ( < or = 0.2 u x mL(-1)), and the level of fibrinolysis product, D-Dimer, increased., Conclusion: rH could inhibit the thrombin binding to fibrin. rH inhibited the activation of TAFI and FXIII by combining with thrombin which resulted in enhancement of thrombolysis.

Objective: To explore the relationship between expression thange of P-selectin after brain injury and secondary brain damage., Methods: Sixty SD rats were randomized into 3 equal groups, namely the control group, mild injury group and severe injury group and animal models of brain injury were established in SD rats according to the method of Feeney. P-selectin expression in the brain tissues were determined at 6 h and l, 3, and 7 days following brain injury (n=5 for each time point). Imaging analysis was performed using computerized imaging technique., Results: P-selectin expression and neutrophil infiltration in the brain tissues increased significantly 6 h after brain injury (P<0.05), reaching the peak level at postoperative 24 h and then gradually decreased., Conclusion: P-selectin expression and neutrophil infiltration increase significantly following brain injury, and the time course and distribution of P-selectin expression are consistent with the secondary damage of the brain, strongly suggesting the involvement of P-selectin upregulation in the secondary insult after brain injury.

Aim: To study the inhibitory effect of 23-HBA on angiogenesis in vitro., Methods: The effect of 23-hydroxy butulinic acid (23-HBA) on the in vitro proliferation of human microcapillary endothelial cells(HMECs) was examined by sulfonylrhodamine B (SRB) assay. The effect of 23-HBA on endothelial cell migration, and tubule formation on Matrigel was also observed. The CD31 expression in HMECs was dectected by immunohistochemical staining., Results: The proliferation of HMECs was inhibited significantly by 23-HBA with IC(50) being 40.44 mg/L. 23-HBA inhibited endothelial cell migration and tubule formation in a dose-dependent manner. The expression of CD31 in HMECs was reduced after treatment with 10 mg/L 23-HBA., Conclusion: 23-HBA can inhibit angiogenesis in vitro, which would become a promising antiangiogenic drug.

Objective: To analyze secondary abdominal surgery after Stark cesarean section., Methods: A retrospective analysis of the secondary operation after cesarean section was performed. Group A was Stark cesarean section (n = 89), group B was the longitudinal incision cesarean section (n = 212), and group C was Pfannenstiel incision cesarean section (n = 52). Stark cesarean section was compared with Pfannenstiel incision cesarean section and the longitudinal incision cesarean section in abdominal wall scar healing, adhesion of rectus muscles, peritoneum, omentum, and healing or adhesion of visceral peritoneum., Results: The rate of good abdominal incision healing and slender scar was 86.5% (77/89) in group A, 29.3% (62/212) in group B, and 75.0% (39/52) in group C, respectively. The rate of adhesion of rectus muscles was 25.8% (23/89) in group A, 53.8% (114/212) in group B, and 13.5% (12/89) in group C, respectively. The rate of adhesion of omentum was 13.5% (12/89) in group A, 56.1% (119/212) in group B, and 25.0% (13/52) in group C, respectively. The rate of peritoneal adhesion was 15.7% (14/89) in group A, 46.2% (98/212) in group B, and 11.5% (6/52) in group C, respectively. Only one case in group C the peritoneum was not healed. The rate of adhesion of visceral peritoneum was 15.7% (14/89) in group A, 55.2% (117/212) in group B, and 13.5% (7/52) in group C, respectively. Abdominal wall scar healing, adhesion of rectus muscles, omentum, peritoneum, and visceral peritoneum in group A were all better than group B. The difference was statistically significant (P < 0.05). There were no differences between group A and group C (P > 0.05)., Conclusions: The study shows that the Stark cesarean section is better than the longitudinal incision cesarean section in healing of abdominal wall scar, adhesion of rectus muscles, omentum, peritoneum, and visceral peritoneum, but compared with Pfannenstiel incision cesarean section, there is no difference statistically. However, the advantages of the Stark cesarean section lie in short surgical time, few injury, little bleeding, quick recovery, and short hospital stay time, thus it should be further popularized.

Objective: To investigate the effect of compound Salvia injection (CSI) on blood coagulatory function in patients with traumatic cerebral infarction (TCI)., Methods: Sixty-four patients with TCI were randomly divided into two groups, 32 in each group. The treated group were treated with CSI plus conventional treatment of western medicine, and the control group treated with conventional treatment alone. Changes of symptoms, levels of plasma P-selectin (P-S), von Willebrand's factor (vWf) and D-dimer were observed with ELISA., Results: The treated group was superior to the control group in Glasgow outcome scale (P < 0.01). Before treatment, the levels of plasma P-S, vWf and D-dimer in the TCI patients were higher than those in healthy people. After treatment, all the parameters lowered in both groups, but the effect of lowering was greater in the treated group than that in the control group., Conclusion: Blood coagulation disorder exists in patients with TCI, CSI could improve it, and might alleviate the cerebral damage to a certain extent.

An analytical method has been developed for directly calculating the principal angle theta(p) at which the phase difference between the two reflection coefficients is equal to 90 degrees and at which the ratio of /r(p)/ to /r(s)/ is equal or close to a minimum. The equations given here can be used in many optical applications. For example, ellipsometric data measured at an incidence angle theta(p) will have higher precision than data measured at other incidence angles. theta(p) is the principal angle. Instead of three principal angles, there is only one principal angle, which can be found in the region of 0 < or = theta(p) < or = 90 degrees for most metallic materials used in applications. Results show good agreement between the measured and the calculated spectra of delta(p) and rho(po).