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Dynamical theories of atomic number sensitive image (or Z-contrast image) formed by thermal diffusely scattered (TDS) electrons are proposed based on first-principles considerations. `Exact' theories are derived for simulating images obtained either in scanning transmission electron microscopy (STEM) using an annular dark-field detector or in transmission electron microscopy (TEM) using an on-axis objective aperture under hollow-cone beam illumination. The atom thermal vibrations are described using lattice dynamics with consideration of phase correlations. The effects that are comprehensively covered in the theory include: dynamical diffraction of the beam before and after TDS, thickness-dependent beam broadening or channelling, Huang scattering from defect regions, coherence of the thermal diffusely scattered electrons generated from the atomic layers packed within the coherent length, multiphonon and multiple phonon excitations, and the detector geometry. Simplified theories have been derived from this unified approach under various approximations. It has been shown that the incoherent imaging theory is a much simplified case of the practical imaging condition, and can be applied only for qualitative image interpretation. The coherent length in the z direction varies with the change of atomic mass in the column. It is thus possible that the z coherence may disappear for heavy elements. Finally, the theory of Huang scattering in high-angle dark-field TEM imaging has been illustrated, and the theoretically expected results have been observed experimentally.

We investigated the effects of cadmium on lung cell DNA in immature mice. The mice were randomly divided into four groups: control group, low-dose group (1/100 LD(50)), middle-dose group (1/50 LD(50)), and high-dose group (1/25 LD(50)); they were supplied with cadmium chloride or control water for 40 days. Lung cells collected from sacrificed mice were used to evaluate the extent of DNA damage by comet assay. The ratio of tailing cells, DNA tail length, DNA comet length, DNA tail moment, DNA olive tail moment, and percentage of DNA in the comet tail were measured. The rate of tailing lung cells exposed to cadmium increased significantly; the low-concentration group had significantly (P0.05) higher rates, and the middle- and high-concentration groups had higher (P0.01) rates compared to the control. DNA tail length, DNA comet length, DNA tail moment, and DNA olive tail moment all increased with the increase in cadmium doses, but compared with those of the control group, no significant differences in low-dose group were found (P0.05), and the differences in middle- and high-dose groups were all highly significant (P0.01). The degree of DNA damage also increased with the increase of the cadmium concentrations. We conclude that cadmium significantly increases DNA damage in lung cells of immature mice in a dose-dependent manner.

In this paper, we assume the platform with visual observer is moved on flat ground and a constrained camera-platform configuration. The constrained camera-platform is used to simplify the camera motion model. Based on the assumption and simplified camera- platform configuration, the 3D camera motion can be separately estimated by planar region alignment between two frames. Firstly, a detected 2D motion between two frames is used to align corresponding planar regions, such an alignment or registration can removes the effects of camera rotation, and the resulting residual parallax displacement field between the two region-aligned images is an epipolar field centered at the FOE (Focus-of-Expansion). Then the camera translation can be recovered from the epipolar field. The camera rotation is recovered from the computed 3D translation and the detected 2D motion. The camera motion model is derived and represented by two parts, and a multistage ego-motion estimation process is introduced. Some experiments with real images demonstrate the robustness of the proposed motion estimation method.

This report gives a review about the study of the novel slow-wave structures and their application in millimeter wave and terahertz band vacuum devices in National Key Laboratory of Science and Technology on Vacuum Electronics(NKLST-VE) in China, including the development of some promising slow wave structures, the design and experiment work of the MM and Terahertz vacuum devices based upon some of these SWSs.

With mycobacteriosis increasing, the study of non-tuberculous mycobacteria is imperative for clinical therapy and management. Nontuberculous mycobacteria are naturally resistant to most anti-tuberculosis drugs. Accordingly, it is important to decipher the biology of the novel non-tuberculous mycobacteria through complete genomic analysis of novel pathogenic mycobacteria. We describe Mycobacterium sinense JDM601, a novel, slow-growing mycobacterium of the Mycobacterium terrae complex resistant to nine antibiotics, by clinical presentation, cultural and biochemical characteristics, minimal inhibitory concentrations, and genome-sequencing analysis. JDM601 is closest to Mycobacterium nonchromogenicum according to mycolic acid composition, but closest to Mycobacterium algericum sp. nov according to 16S rDNA. JDM601 is resistant to isoniazid, streptomycin, rifampin, euteropas, protionamide, capromycin, ciprofloxacin, amikacin and levofloxacin but not ethambutol. The clinical information, mycolic acid composition, and virulence genes indicate that JDM601 is an opportunistic pathogen.

In studying the multiple scattering of acoustic waves by a half-space of distributed discrete scatterers, the quasicrystalline approximation(QCA) approach together with the hole correction (HC) or the pair distribution functions (PDF) have been used extensively, in which a system of simultaneous equations must be solved to determine the effective propagation constant and the expansion coefficients of the coherent exciting field. In this paper, we analyse the same problem under Foldy's approximation (EFA) by using the so-called modified T-matrix approach (MTMA) which was first proposed by Twersky. Two equations in a considerably simple and clear form are obtained for determining the effective propagation constant and the amplitude of the coherent transmitted field, as the scatterers are identical spheres. The numerical results in the low-frequency limit are also discussed in brief.

In studying the multiple scattering of acoustic waves by distributed discrete scatterers, the ‘two-exterior’ T-matrix or the modified T-matrix is needed. In this paper, the modified T-matrix formulae for a scatterer of arbitrary shape are derived, based on Huygen's principle and the method of optimal truncation (MOOT), respectively. Analytical expressions are given for the modified T-matrix elements of a spheroid in the low-frequency limit. The agreement with the existing results is shown to be exact to the given order of ka. It is also shown that the results based on Huygen's principle are merely the special cases of those based on MOOT.

Rare earth complexes ofm-nitrobenzoic acid (LnL3·2H2O,Ln=La-Lu and Y, except Pm, HL=m-nitrobenzoic acid) were synthesized and characterized by elemental analysis, chemical analysis, IR spectroscopy and X-ray diffraction analysis. The dehydration behaviour of these complexes was studied in detail by means of TG-DTA and DSC. Dehydration occurs over the temperature range 76–215°C, and the temperature of formation of the anhydrous complexes decreases with increasing atomic number of the rare earth. The activation energies and enthalpy changes for te dehydration were obtained.

In studying multiple scattering of electromagnetic waves by distributed discrete scatterers, the 'two exterior spaces' T-matrix or the modified T-matrix is needed. In this paper, the modified T-matrix formulae for a scatterer of arbitrary shape are derived, based on Huygen's principle of scattered waves and the method of optimal truncation respectively. Analytical expressions are given for the modified T-matrix elements of a spheroid in the low-frequency limit. Agreement with existing results is shown to be exact to the given order of ka. It is also shown that the results based on Huygen's principle are merely special cases of those based on the method of optimal truncation.

In studying multiple scattering of waves by a half-space of distributed discrete scatterers, the approach of the quasi-crystalline approximation together with hole correction or pair distribution functions has been used extensively. In this approach a system of simultaneous equations must be solved to determine the effective propagation constant and the expansion coefficients of the coherent exciting field. In this paper, we analyse the same problem under Foldy's approximation by using the so-called modified T-matrix approach. Two simple and clear equations are obtained for determining the effective propagation constant and transmission coefficient of the coherent transmitted field when the scatterers are identical spheres. The expressions for the coherent reflected field and incoherent scattered intensity are also given. It is shown that, in the limit of low frequency and sparsely distributed scatterers, our solutions reduce to the well-known results. The numerical results for ka=0.2 also show that our results with the modified T-matrix and Foldy's approximation are better than Foldy's approximation alone, but are still worse than the quasi-crystalline approach with pair distribution functions and Monte Carte simulations because we have not incorporated the pair distribution functions into our modified T-matrix approach. It should be pointed out that the modified T-matrix approach can be generalized to the case of pair distribution functions in which the exciting field is also travelling with the effective propagation constant.

Hepatitis B virus (HBV) genotypes/mutants are known to affect natural outcomes. The virologic differences among HBV genotype, precore and basal core promoter (BCP) mutations were investigated. HBV strains were isolated from 18 hepatitis B e antigen (HBeAg)-positive patients (nine genotype B and nine genotype C). All had precore and BCP wild-type sequences. After cloning of full-length HBV genome, the effects of viral genotype, precore and BCP mutations singly or additively on the expression of viral DNA and antigens were investigated by mutagenesis and transfection assays in Huh7 cells. Significant findings included the following: (i) expression of intracellular core protein increased when precore or BCP mutation was introduced in genotype C strains; (ii) expression of intracellular surface protein was lower in genotype C precore wild-type strain compared with genotype B; (iii) precore mutation was associated with a lower extracellular expression level of HBV DNA; (iv) secretion of hepatitis B surface antigen in genotype C was lower than that in genotype B; and (v) secretion of HBeAg in genotype B was lower than that in genotype C. No additive effect was observed by combining precore and BCP mutations. Hence, HBV genotype and precore/BCP mutations correlate with intrahepatic expression of viral antigens in vitro.

The objective of this study is to investigate the strength behavior and plastic limit pressure of hot-tapped pipelines under an internal pressure load. Two full scale test models were fabricated for the experiment. A three-dimensional nonlinear finite element analysis was also carried out. The plastic limit pressure was determined approximately by use of the twice the elastic-slope criterion. The results indicate that plastic limit pressures obtained by experiment and finite element analysis are in good agreement. On the basis of the above results, a parametric analysis of the plastic limit pressure was carried out and resulted in the development of formulas useful for the design of hot-tapped pipelines.

It has been shown that grating based x‐ray phase contrast imaging (GPI) can be performed on x‐ray tubes and therefore has a great potential for a wide application in many fields. So far to extract and to separate the phase information from other contributions, a phase‐stepping approach is normally adopted. One of the gratings is scanned transversely to the incident beam while acquiring multiple projections of the sample. However, during the grating scanning, the sample is supposed to be static, and the resulting poor time resolution is one of the major drawbacks of this method. It is clear that a method that would extract the phase information without the need of multiple stepping would be a breakthrough enabling fast, highly sensitive (phase‐contrast) x‐ray imaging. According to the similar physics and mathematics between diffraction enhanced imaging (DEI) and GPI, here we report how the DEI methods can be generalized for GPI and how GPI can use the same acquisition procedure as the conventional absorption CT without grating scanning.

Uranyl luminescences in phosphoric acid system has been studied. Uranyl excited by a nitrogen laser shows single or biexponential luminescence decays in the phosphoric acid system. When the uranyl ion or phosphoric acid concentration are lower, a single exponential luminescence decay appears, whereas at higher uranyl ion or phosphoric acid concentrations, biexponential decay is observed. Time-resolved spectra of uranyl in this system are measured. The reasons of the phenomena are tentatively established.

Electron-energy-loss spectroscopy for the oxygen K edge was performed at and near grain boundaries of YBa 2 Cu 3 O 7 using an electron beam of 20 A diameter in a transmission electron microscope. The analysis of the pre-peak at the absorption edge revealed that there exist both oxygen-deficient (100 A or less wide) and fully oxygenated grain boundaries. These differences depend on the structural misorientations between grains separated by boundaries. The results were consistent with earlier predictions of variable oxygen contents at YBa 2 Cu 3 O 7 , grain boundaries, depending on the misorientations, based on the constrained coincident-site lattice model for the boundary structures

A novel hypderchaotic system with two larger Lyapunov exponents and wider parameter range is built based on the three-order Qi chaotic system. The properties of this system are studied detailedly, such as the balance point and stability, Lyapunov exponent spectrum and the fractal dimension, and the phase portraits of hyperchaotic attractor. A practical circuit is designed to realize the system by EDA technology based on FPGA platform. The experimental result is in full accord with the simulation result‥

A full-range shear experiment of 6 groups with 18 specimens was carried out to investigate the effective adherence of new and old concrete in structure strengthening. The influence of various techniques to interface shear properties is examined. The experiment results show that the shear strength of the interface can be improved remarkably with bonded-in reinforcement. Based on the research results, the practical calculation formula was put forward which can take account of the influence of roughness, agent and bonded-in reinforcement. The formula was also validated by other experiments and can be used in the strengthening design for concrete structure.

SUMMARY Cleaved α-aluminium oxide (0,1,2) surfaces are studied using combined techniques of scanning reflection electron microscopy and reflection electron energy-loss spectroscopy. An α-aluminium oxide (0,1,2) surface can terminate with a layer of either oxygen or Al atoms depending on where the bonds break. Aluminium metal can be reduced only from the domains initially terminated with oxygen by an intensive electron beam. The interpretation of this damage effect is based on the desorption process of oxygen atoms after Auger decay. The resistance to beam damage of the domains initially terminated with Al is found to be due to the protection of the surface adsorbed amorphous oxygen layer.

The effects of two structurally similar pyrazine derivatives, tetramethylpyrazine (TMP) and tetraethylpyrazine (TEP) on the contractile responses of dog saphenous vein to KCl (via membrane depolarization), phenylephrine (PHE, α1-adrenergic agonist), and B-HT 920 (α2-adrenergic agonist) were investigated. The relaxant or inhibitory effect of TMP and TEP was most potent on KCl-induced responses and least potent on PHE-induced responses. Their effect on KCl-induced responses was more prominent at 30 mM KCl than at 100 mM KCl. In Ca2+-free medium, PHE and B-HT 920 elicited transient responses, which were also markedly and reversibly inhibited by TMP and TEP. Similar results were also obtained when prostaglandin F2α was used as an agonist. In all four types of contractile responses involving different receptors, the inhibitory effect of TEP was consistently more potent than that of TMP. We conclude that both TMP and TEP behave as a nonselective smooth muscle relaxant having similar and multiple actions including their general interference with the processes involving both Ca2+ entry and intracellular Ca2+ release.Key words: vascular smooth muscle, calcium channels, tetramethylpyrazine, tetraethylpyrazine, α-adrenoceptors, saphenous vein.

Based on the acid rain observation data and the contemporaneous historical synoptic charts of Mid-Eastern Fujian during the period of 1991 to 2003, we analyzed the distribution characteristics of acid rain in different seasons, weather types, precipitation grades and wind directions. The results showed that the acid pollution in Mid-Eastern Fujian was still serious. In winter, the precipitation pH value was 4.79, and the acid rain frequency was 60.62% which was twice higher than that in summer. The pH value of warm shear-type precipitation at 850 hPa was 4.79. Nearly half of these precipitations had the problems of acid rain pollution. The acid rain frequency of the inverted trough type was only 26.11% which was the lowest one in all types. There was no marked difference of the acid rain distribution characteristics between ahead-of-trough and behind-the-trough. The precipitation pH values of the five grades were lower than 5.30 and the acid rain frequency changed as an inverted U shape with the increasing of the rainfall. The pH values of precipitations in the eight wind directions were generally below 5.20, and the acid rain frequencies were about 40%.

The structural response of coexisting multiple martensites to stress field in a Ni-Mn-Ga multifunctional alloy was investigated by the in situ high-energy x-ray diffraction technique. Stress-induced transformation between coexisting multiple martensites was observed at 110 K, at which five-layered modulated (5M), seven-layered modulated (7M) and non-modulated (NM) martensites coexist. We found that a tiny stress of as low as 0.5 MPa could trigger the transformation from 5M and 7M martensites to NM martensite and this transformation is partly reversible. Besides the transformation between coexisting multiple martensites, rearrangement of martensite variants also occurs during loading, at least at high stress levels. The present study is instructive for designing advanced multifunctional alloys with easy actuation.

To prepare monoclonal antibodies against West Nile virus (WNV) envelope protein domain.BALB/c mice were immunized with recombinant antigen of West Nile virus envelope protein domain, and the spleen cells of the mice were used to prepare the monoclonal antibodies (McAb) by hybridoma technique.Three hybridoma cell strains secreting McAbs against WNV envelope protein domain, designated as 4F7, 6H3 and 8E4, respectively, were obtained and were identified by indirect enzyme linked immunosorbent assay (ELISA), they belonged to IgG1, IgG1 and Ig2a, respectively. Two epitopes of envelope protein domain were determined, among them, 4F7 and 6H3 were against the same epitope and 8E4 to another one.The results of indirect ELISA, Western blot and indirect immunofluorescence experiment indicated that these three McAbs were specific for West Nile virus envelope protein domain and did not cross-react with Japanese encephalitis virus and other viruses, so they can be used for specific detection of West Nile virus.

We report a size-manipulable synthesis of single-crystalline nanorods/nanowires of barium manganite (BaMnO(3)) and barium titanium manganite (BaTi(1/2)Mn(1/2)O(3)) by using the composite-hydroxide-mediated approach. The synthesis cleanly yields nanorods with a hexagonal perovskite structure. Typical nanorods have widths ranging between 50 and 100 nm, and the lengths can be easily controlled by time and temperature or by adding a small amount of water during the synthesis process. Resistance measurement shows that a phase transition happened at 58 K on BaMnO(3). The photoluminescence spectrum of BaTi(1/2)Mn(1/2)O(3) presents two emission peaks at wavelengths of 465 and 593 nm, corresponding to blue and green fluorescence. The ability to synthesize nanorod manganites of a desired length should enable detailed investigations of the size-dependent evolution of magnetism, magnetoresistance, nanoscale phase separation, and realization of a nanodevice of magnetic sensors.

Seven-nanometer cobalt nanocrystals are synthesized by colloidal chemistry. Gentle annealing induces a direct structural transition from a low crystalline state to the hexagonal close packed (hcp) phase without changing the size, size distribution, and the lauric acid passivating layer. The hcp structured nanocrystals can be easily redispersed in solvent for further application and processing. We found that the magnetization at saturation and the magnetic anisotropy are strongly modified through the annealing process. Monolayer self-assembly of the hcp cobalt nanocrystals is obtained, and due to the dipolar interaction, ferromagnetic behavior close to room temperature has been observed. This work demonstrates a novel approach for obtaining small size hcp structured cobalt magnetic nanocrystals for many technological applications.

A uniform nanolayer of europium-doped Gd2O3 was coated on the surface of preformed submicron silica spheres by a Pechini sol-gel process. The resulted SiO2 @ Gd2O3:Eu3+ core-shell structured phosphors were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as kinetic decays. The XRD results show that the Gd2O3:Eu3+ layers start to crystallize on the SiO2 spheres after annealing at 400 degrees C and the crystallinity increases with raising the annealing temperature. The core-shell phosphors possess perfect spherical shape with narrow size distribution (average size: 640 nm) and non-agglomeration. The thickness of the Gd2O3:Eu3+ shells on the SiO2 cores can be adjusted by changing the deposition cycles (70 nm for three deposition cycles). Under short UV excitation, the obtained SiO2@Gd2O3:Eu3+ particles show a strong red emission with 5D0-7F2 (610 nm) of Eu3+ as the most prominent group. The PL intensity of Eu3+ increases with increasing the annealing temperature and the number of coating cycles.

A vapor phase transport growth process has been developed to synthesize ZnO quantum dots (QDs) on Si substrates. The characteristics were investigated for as-prepared ZnO QDs without any additional treatment. The formation of ZnO QDs with 6 nm in height and 15 nm in diameter is confirmed by scanning electron microscope and atomic force microscopy. Room-temperature photoluminescence reveals that the as-prepared ZnO QDs exhibit a predominant ultraviolet emission at 3.32 eV while the low energy defect-related blue-green emission is significantly quenched. The band gap of ZnO QDs is determined to be 3.41 eV, which evidently indicates the quantum confinement effects.

In this article, we demonstrated the synthesis of metallodielectric composite particles comprising a metal shell on a dielectric core and an outer coating of an insulating dielectric layer by depositing silver on silica supporting cores followed by coating of titania. A combination of surface reaction and surface seeding techniques is exploited for the formation of a complete silver shell on silica spheres. The additional outer coating of titania on silver shell particles is then performed by hydrolyzing tetra-n-butyl titanate in ethanol at room temperature. The morphologies of silver shells and titania coating are studied with electron microscopy, and their existences are confirmed with X-ray diffraction and energy-dispersive X-ray measurement.

The Kanggurtag gold belt is located in the eastern Tianshan Late Paleozoic orogenic belt, where three types of gold deposit are developed on the south margin of an east-west-trending ductile shear zone. From a tectonic point of view, we suggest that gold mineralization is dominantly controlled by post-collisional dextral strike-slip faults, and gold resources are the product of the same metallogenetic event in the Late Carboniferous-Early Permian. The spatial distribution of different types of gold deposits is restricted to different strain distribution along the shear zone. This proposed structural model has important implications for further exploration in this belt.

On the basis of previous studies, this paper provides a preliminary summary of recent research on mafic-ultramafic intrusions and related magmatic Cu-Ni sulfide ore deposits in northern Xinjiang. The authors argue that there is still a need to study some key problems concerning the origin and tectonic settings of these intrusions and sulfide deposits.

Interface microstructures of BaTiO3/LaAlO3 grown by metalorganic chemical vapor deposition (MOCVD) are studied using high‐resolution transmission electron microscopy (HRTEM). Interface dislocations in BaTiO3/LaAlO3 have been shown to be directly linked up with the 90° domain boundaries in BaTiO3. This association is a result of strain relief due to a phase transformation when cooled down from the growth temperature. The Burgers vector of the interface dislocations is 〈010〉.

Shock compaction was used to consolidate exchange‐coupled R2Fe14B/α‐Fe (R=Nd, Pr) hard/soft phase nanocomposite powders using a three‐capsule plate‐impact gas‐gun loading system. Design of the consolidation fixture, densification conditions, and starting powder properties allowed control of the final density and microstructure of the shock‐compacted samples. Highly dense compacts (∼99% of full density) with minimal interparticle melted/re‐solidified zones and free from macrocracks were obtained under optimum consolidation conditions, in which case a laminar microstructure of the ribbon‐shaped powders was observed. TEM characterization revealed complete retention of the nanostructure of the hard and soft phases, which grain sizes were within 20–25 nm in the final shock‐compacted composite magnets. Retention of nanostructure ensured exchange coupling between the hard and soft phases, resulting in magnetic properties in the shock consolidated compacts similar to those of starting powders.

To investigate the signal transduction pathway of NF-kB activated by minimally modified low density lipoprotein (mm-LDL) in endothelial cells and the effect of NF-kB on platelet derived growth factor b (PDGFb) mRNA expression.mm-LDL was prepared through iron oxidation by dialyzing the native LDL against FeSO4 in PBS. Endothelial cells were incubated in a medium containing mm-LDL, TNF, and IL-1 respectively and electrophoretic mobility shift assay (EMSA) was displayed to check on the activation of NF-kB. Luciferase reporter gene was analysed to investigate the effect of nuclear factor inducing kinase (NIK), inhibitor of NF-kB kinase alpha (IKK alpha) and inhibitor of NF-kB kinase beta (IKK beta) on NF-kB activation. In addition, endothelial cells were transfected using PDGFb promoter-luciferase for reporter gene analysis or transfected with mut-NIK for slot blot analysis to study the effect of NF-kB on PDGFb mRNA expression.mm-LDL was able to activate NF-kB in endothelial cells. mut-NIK and mut-IKK beta inhibited luciferase activity induced by mm-LDL. mm-LDL could also enhance luciferase activity controlled by upstream sequence of PDGFb promoter which contains element interacting with NF-kB. Result of slot blot showed inhibition of PDGFb mRNA expression by mut-NIK in the endothelial cells stimulated by mm-LDL.mm-LDL may activate NF-kB through NIK-IKK beta pathway and promote PDGFb mRNA expression in endothelial cells.

Study on (1) inhibition of oxidized low density lipoprotein (oxLDL) effect on the uptake and clearance of intra-cellular 3H-cholesterol in vascular smooth muscle cells (v-SMC) originated from the human-apoAI transgenic mice (C57BL/6); (2) change of human-apolipoprotein AI (h-apoAI) mRNA expression in v-SMC after oxLDL stimulation and the protective effect of expressed h-apoAI on v-SMC against oxLDL intoxication.(1) v-SMC isolated from human apoAI transgenic mice possessing a recombined gene connected beforehand with a mouse metallothionein-I (MT-I) as the promoter; (2) study of h-apoAI mRNA expression from v-SMC of the transgenic mice by RT-PCR and Northern blot.oxLDL (30 micrograms/ml) strongly promoted v-SMC proliferation. No difference found on 3H-cholesterol uptake between smooth muscle from normal mouse aorta (n-SMC) and smooth muscle cells from transgenic mouse aorta (tr-SMC) of the control groups, the uptake rates of both kinds of SMC rose 100% after oxLDL stimulation. The efflux rates of 3H-cholesterol in tr-SMC were much higher than those of n-SMC (40%-50%). After oxLDL stimulation, the clearance rates fell by 28% and 10% respectively for n-SMC and tr-SMC. The result of RT-PCR and Northern blot showed a marked increase of h-apoAI gene expression after oxLDL stimulation.Expression of h-apoAI gene in C57BL/6 mice enables to decrease the accumulation of cholesterol in v-SMC. tr-SMC are capable to alleviate the harmful effect of oxLDL on v-SMC due to the increase of h-apoAI expression.

Crystalline nanobelts of ZnO and SnO2 were prepared from a thermal evaporation of oxide powders inside an alumina tube in the absence of catalysts. Typical dimensions of the nanobelt samples ranged from approximately 10 to 100 microns in length, 30 to 300 nm in width, and 6 to 30 nm in thickness. Room temperature Raman spectra were obtained on pressed mats of nanobelt samples and compared with the corresponding spectra of the starting oxide powders and bulk materials. Collectively, our Raman data indicated that the as-prepared nanobelt samples used in this study were oxygen deficient. Upon annealing at 900 degrees C in flowing oxygen for 1 h, the nanobelt samples exhibited Raman features that corresponded to those expected in respective bulk semiconducting oxides. The dimensions of the nanobelts were a bit too large to expect significant quantum size effects on the phonon structure similar to those observed in carbon nanotubes and short-period semiconductor superlattices.

The maize CMS-S near isogenic line (NIL) developed by author and the backcross progeny (BC1) derived from it were used to identify molecular markers linked to the Rf3 gene and subsequently determine its chromosomal location on the linkage map of maize. Bulk segreant analysis was performed using AFLP technique. From the survey of AFLP primer combination, two AFLP markers, (EcoRI-AGG/MseI-CAC and EcoRI-AAC/MseI-CAG), which were named RR6 and RR7 respectively, linked to the Rf3 gene were identified. However, AFLP marker RR6 showed polymorphism between parents, and bulks were used to survey the available 100 individuals of the BC1 population, 2 out of 100 shed recombination. The recombination-rate was 2%. The genetic distance between Rf3 gene and AFLP marker RR6, was approximately 2.0 cM. And then, the RR6 was successfully cloned and sequenced, primer synthesized and converted to SCAR marker so that PCR marker can be developed for the marker-assisted selection. In RFLP analysis, marker RR6 linked to Rf3 was found to be located between RFLP loci asg20 and php20581b, and mapped on chromosome 2L.

Based on the analysis of the substrate permeabling through the cytoplasmic membrane, the corresponding simple transport models are proposed. By coupling of the model with the Monod kinetics, it was discovered that form of Monod kinetics doesn't change, but the kinetics parameter affected by the transport processes. This result is fit well with the literature conclusion and experimental data.

Inducible nitric oxide synthase (iNOS) is up-regulated in rejecting allografts and is protective against allograft arteriosclerosis; it suppresses neointimal smooth muscle cell accumulation and inhibits adhesion of platelets and leukocytes to the endothelium. However, the functional importance of endothelial NOS (eNOS) in the rejecting allografts remains unclear.We examined the effects of selective eNOS deficiency in aortic allografts in a murine chronic rejection model using grafts from eNOS knockout (KO) mice (C57BL/6 background; H2b) and normal C3H (H2K) as recipients. Grafts from wild-type C57BL/6 mice served as controls. Grafts from iNOS KO mice served as a second group of controls where the contribution from iNOS was eliminated but eNOS was preserved. Aortic grafts were harvested and analyzed at days 10-14, 18-22, and 26-30 after transplantation.Endothelial NOS-deficient grafts showed significantly increased intima/media ratios at days 26-30 compared to controls. Immunostaining demonstrated that in eNOS KO grafts, eNOS was not detectable whereas iNOS was expressed prominently in infiltrating recipient mononuclear cells. In control grafts, eNOS expression was preserved in the endothelium even by day 30, and associated with a decrease in intimal thickening. We further demonstrated that early overexpression of iNOS by ex vivo gene transfer completely prevented the development of arteriosclerosis associated with eNOS deficiency.We found that eNOS plays a protective role in allografts, and that in eNOS-deficient allografts, early overexpression of iNOS is capable of preventing the development of allograft arteriosclerosis. In allografts with dysfunctional vascular endothelium and impaired eNOS activity as a result of ischemia or native arteriosclerotic disease, iNOS gene therapy may serve to improve their long-term survival and function.

Nanocrystalline diamond films were grown by microwave plasma assisted chemical vapor deposition using N-2 and CH4 as precursors. The microstructure of the films such as the diamond grain size, graphite content, and N incorporation, was controlled by introducing a small amount of hydrogen gas (0-10 sccm) in the growth. Effects of the growth parameters on the film microstructure were investigated using transmission electron microscopy, x-ray diffraction, Raman spectroscopy, and secondary ion mass spectroscopy. A surface stabilizing model is suggested to explain the formation mechanism of the uniformly grain size-controlled nanocrystalline diamond. A systematic investigation on the film microstructure and their field electron emission (FEE) property is presented for various films of different diamond grain sizes and graphite contents. It was found that the FEE property highly depended on the diamond/graphite mixed phase structure. Novel field emission properties (1 V/mum emission threshold and 10 mA/cm(2) emission current) are obtained by optimizing the growth parameters. A transport-tunneling mechanism is applied to explain the experimental observations. Our results showed that nanocrystalline diamond film can be a very promising cold cathode material for field emission applications. (C) 2000 American Institute of Physics. [S0021-8979(00)07117-6].

The present experiment was designed to study the mechanism underlying the stimulatory effect of histamine (HA, i.c.v.) on the gastric acid secretion in subdiaphragmatic vagotomized SD rats. Gastric acid was continuously washed out with 37 degrees C saline by a perfusion pump. Drugs were injected into the third ventricle or the vein to examine the effect on gastric acid secretion and the level of plasma corticosterone. The results are as follows: (1) HA (1.0 microgram, i.c.v.) potentiated gastric acid secretion induced by G-5, which could be abolished by preintramuscular injection of diphenhydramine hydrochloride (8.0 micrograms). (2) Corticotropin-releasing factor (CRF) (0.5 microgram, 1.0 microgram, i.c.v.) augmented gastric acid secretion in a dose dependent manner. (3) HA (1.0 microgram, i.c.v.) increased the plasma corticosterone level. (4) Intravenous injection of corticosterone 21-sulfale (15, 30 micrograms) augmented gastric acid secretion in a dose dependent manner. These results suggested that intracerebroventricular injection of HA could stimulate the release of CRF by specificably binding with H1 receptor in some areas of hypothalamus, which, in turn, increased gastric acid secretion induced by G-5 via increasing the level of plasma corticosterone.