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Polysaccharides from litchi (Litchi chinensis) seeds were isolated and purified using ion exchange column chromatography. Molecular weight distribution of polysaccharides and monosaccharides were detected. Preliminary structural characterisation of polysaccharides was conducted using infrared, nuclear magnetic, and other spectroscopy techniques in combination with methylation analysis. In vitro cell culture experiments were designed to detect the effects of polysaccharides on cell growth and cellular glucose consumption. We extracted and analysed three polysaccharides from litchi seed. Monosaccharide composition and infrared spectroscopy detection showed that the skeleton structure of polysaccharides consisted of glucose and mannose. Polysaccharides 1 and 2 are similar and have relatively high glucose content (around 70%); polysaccharide 3 has 39.17% glucose only but is rich in arabinose (about 21.03%). In a certain range of use (50~1000 μg ml–1), polysaccharides 1 and 2 have no significant impacts on cell growth, while polysaccharide 3 can promote proliferation to some extent. All three polysaccharides can promote in vitro cellular glucose consumption, especially polysaccharide 3, which shows the strongest promotion, a significant dose effect, and synergistic effect with insulin. The above results highlight important roles of litchi seed polysaccharides in promoting cell growth and validate litchi seed polysaccharides as potential drugs for hypoglycaemia.

The effects of laser peening (LP) with different laser peening coverage rates on residual stresses and fatigue crack growth (FCG) properties of Ti–6Al–4V titanium alloy were investigated. Residual stresses after LP and micro-structure with different fatigue striation patterns on fracture cross-sections were analyzed. Compressive residual stresses and dense dislocation arrangements can be obtained in the superficial layer after LP. The influence of compressive residual stresses induced under different LP coverage rates on FCG properties was revealed. LP coverage rate had an apparent influence on FCG properties as confirmed by the fatigue striation spacing on fracture cross-sections. Moreover, FCG rate decreased with the increase of compressive residual stresses perpendicular to the crack growth direction, which indicated that LP had an obvious inhibitory effects on FCG.

Buffalo grass [Buchloe dactyuloides (Nutt.) Engelm.] plants can be either male, female, or hermaphrodite (monoecious). As there is no morphological difference in the early vegetative growth of these three classes of plants, it is worthwhile to use molecular biological methods to attempt to identify the sex of a plant at this early growth period. In this study, we identified 23 plants that had a stable sex for over at least 3 years. Of these, 9 were male plants, 10 were female plants, and 4 were hermaphrodites. Screening of 300 RAPD primers identified a primer, namely S211 (5'-ttccccgcga-3'), which is capable of identifying male plants. The specific fragment was cloned, sequenced, and submitted to the GenBank database (accession No. JN982469). When used to identify the sex of 188 plants during their first growing season, the S211 primer correctly identified 85.8% of all male plants. Our results showed that the S211 primer can identify the male, and in doing so, it facilitates buffalo grass breeding work.

BACKGROUND AND PURPOSE: We reported the MR findings of spinal metastatic lesions after SRS according to the volumetric changes (in press). However, in the case of osteoblastic metastatic lesions, tumor volume usually doesn9t change during remission. In this study, we retrospectively analyzed pre- and post-SRS CT and MR imaging findings of locally controlled osteoblastic spinal metastatic lesions besides volumetric changes MATERIALS AND METHODS: Among 113 spinal metastatic lesions in 72 patients, 10 lesions were osteoblastic. CT and MR images were reviewed to identify 4 parameters: 1) changes in tumor volume, 2) changes in CT attenuation, 3) changes in T2 signal intensities and 4) changes in degrees of contrast enhancement. RESULTS: Tumor volume was unchanged in 9 lesions and increased in 1 lesion. CT attenuation increased in 7 lesions and T2 signal intensities were heterogenous with dark signal foci within the tumor in 3 of 7 lesions and with dark and bright signal foci within the tumor in 4 of 7 lesions. In 3 lesions where CT attenuation decreased, T2 signal intensity became heterogenous with dark and bright foci in 2 of 3 lesions and T2 signal intensity became normalized in 1 lesion. The degree of contrast enhancement decreased in 8 lesions but 2 lesions showed persistent contrast enhancement. CONCLUSIONS: Further progression of sclerotic changes was a more common finding than loss of sclerotic foci. Main MR imaging features of osteoblastic lesions after treatment were development of dark with or without bright signal foci, with decrease in contrast enhancement.

In the experiments reported here, we used the female ladybirdCoccinella septempunctataL. as a model to identify diapause-associated proteins using proteomics technology. Our results indicated that protein expression patterns of diapausing and nondiapausing individuals were highly differentiated. A total of 58 spots showed significant differences in abundance (Ratio > 2 andP< 0.05) according to two-dimensional electrophoresis and GE Image Scanner III analysis. Sixteen protein spots were further investigated using mass spectrometry. Eight proteins were characterized, including chaperones and proteins involved in glucose metabolism, lipid metabolism, and the tricarboxylic acid cycle. Among these proteins, five proteins were upregulated in diapausing female adults, including a chaperone (Symbionin symL), malate dehydrogenase (putative), two proteins linked to lipid metabolism (unknown and conserved hypothetical protein) and phosphoglyceromutase (partial). By contrast, isocitrate dehydrogenase (RH49423p), fumarylacetoacetate hydrolase (AGAP001942-PA), and a putative medium chain acyl-CoA dehydrogenase were downregulated. These results contribute to the understanding of diapause mechanisms of the ladybirdC. septempunctataand may suggest methods for improving the application of this natural enemy insect.

The inner and outer car panels for bonnet, door, and trunk lid are assembled by hemming rather than welding. To achieve successful fabrication of these panels, the complicated timing chart of hemming units for pre-and main hemming stages should be made to optimal one. In this study, a design system for automatic timing chart generation is developed. Using AutoCAD VBA and EXCEL data chart, hemming die design parameters and guidelines were put into the program to give hemming unit drawings and consequent timing charts. Then the prepared timing charts were checked and modified. The effectiveness of the system is verified by applying it successfully to hemming unit design for bonnet panel joining.

The multi-target localization method for distributed multiple-input multiple-output (MIMO) radar is investigated in this paper. A geometric-model-based method is proposed for multi-target localization and it is still efficient in the case when some targets with multiple spatial reflections become unobservable in some transmitter-receiver channels. Weight coefficients are used to determine the position of targets. Simulation results demonstrate that the proposed method effectively accomplishes multi-target localization with the distributed MIMO radar across scattering cross-section (RCS) and it outperforms the existing method both at search time and localization accuracy.

Ternary Al2O3-ZrO2-Y2O3 samples with a eutectic composition were prepared using the rapid quenching method, with some samples further annealed at 1300°C for 30 min and then slow cooled. The microstructural evolution was observed with XRD, SEM, and TEM. The SEM and TEM observations of the ternary samples agreed with the XRD. The rapid quenched sample was an amorphous phase with a small amount of crystalline phase mixed in. Observations showed that the rapid quenched and annealed sample was completely crystalline with a granular structure and well defined crystals of 40-60 nm in size.

A quasi-monochromatic X-ray source based on a KAERI SC linac system has been designed and is being manufactured now. 10 MeV 10 mA electron beam together with 20 W 1.06 μm laser beam will be used for 1.8 keV Compton X-ray generation with a few percentage of energy spread and 10 7 photons /s flux. A simple straight beamline was designed to deliver the electron beam with no degradation of its emittance and energy spread and to focus it to a proper size to produce the desired X-rays. We expect the first demonstration of 1.8 keV Compton X-ray generation in autumn 2006.

A project of a high-power FEL at Korea Atomic Energy Research Institute is described. The FEL is driven by a superconducting energy recovery linac. The future ERL will be connected to the existing machine without any modification. It consists of two 180° bents and two straight sections: one is for the FEL, another for a Compton X-ray source. One can choose the regime controlling the lenses. The total ERL is isochronous to avoid any problem with longitudinal beam instability. The total relative emittance degradation through the whole machine is ≈1.5. The FEL will be based on a 2 m helical in-vacuum undulator made of permanent magnets. One mirror of the optical cavity is blind and made of copper, the other one, the outcoupler, is semi-transparent and made of CVD diamond. The expected average power is a few kW, the tuning range 35–70 μm.

The role of friction between the microhardness indenter and the test specimen is addressed through the analysis of dry (unlubricated) and lubricated tests on iron by Atkinson and Shi. Quantitative evaluation through a proportional specimen resistance model accurately describes the results. It suggests that friction is a major portion of the observed hardness increase at low test loads, the indentation size effect. The ISE is related to the surface-area-to-volume ratio of the indentation, which is inversely related to the indentation dimension.

This paper considers the problem of designing a feeding buffer included in a manufacturing system, in combination with a manufacturing shop equipped with multiple pallets where items (raw material) are periodically delivered in batches, according to the “order up to R” inventory policy from a central warehouse to the local feeding buffer and then loaded by pallet for processing at the manufacturing shop whenever pallets are available. The objective is to determine the optimal storage capacity of the feeding buffer, for which the problem analysis is made in a periodic-review inventory model approach under the assumptions that demand rates at the manufacturing shop are dependent on on-hand raw-item inventory (state-dependent) and the periodic review interval is given. In the problem analysis, a sufficient condition for the total cost function to be convex is derived. Therewith, the problem solution is found so as to minimize the sum of the expected inventory holding costs and the expected production loss (due to raw-item shortage) costs.

The power loss characteristics of Mn-Zn ferrites were observed up to 1 MHz at 25 mT as a function of temperature. At 100 kHz the temperature at which the power loss minimum occurred was near 70/spl deg/C, at 500 kHz 50/spl deg/C and at 1 MHz even lower. The contribution of eddy current loss to the temperature dependence of the total power loss was negligibly small at 1 MHz because the resistivity is independent of temperature. The contribution of the residual loss due to magnetic rotation was significant and strongly temperature dependent at 1 MHz. The frequency where the residual loss starts to increase was in good agreement with the onset frequency of dissipation of the complex permeability.

The effect of oxygen partial pressure during sintering process on the electromagnetic properties of Mn-Zn ferrites has been studied. Equilibrium oxygen partial pressure was precisely controlled according to log Po/sub 2/=A-14540/T(K). At low oxygen partial pressure, significant Zn volatilization as well as loss of oxygen was observed. As the oxygen parameter (A) decreased from 8.2 to 7.6, the power loss minimum and the second maximum of initial permeability moved to lower temperatures. These shifts were not clearly observed with oxygen parameters below 7.6. The core sintered at A=7.0 showed the prominent second permeability peak.

Summary form only given. The use of Bi/sub 2/O/sub 3/ additive for promoting the sintering of NiCuZn ferrites is examined. The Bi/sub 2/O/sub 3/ content dependences of the grain size, abnormal grain growth, bulk density, permeability and quality factor are presented.

The sintering temperature significantly changed the microstructure and effected the power loss behavior at the frequency range over 100kHz. The best power loss characteristics at l00kHz-200mT and 500kHz-50mT were observed in the samples sintered at 1300°C and 1250°C, respectively. Those results indicated that the power loss depended on the grain size, electrical resistivity and density of sintered cores. To maintain the stoichiometry at the sintering condition, the ferrite cores were processed on the isocomposition lines within the spinel phase boundary when being cooled. The zinc vapor pressure as well as the oxygen partial pressure was controlled. The high zinc loss condition had an adverse effect on the microstructure of the sintered core surface and degraded the power loss characteristics.

Ferroelectric superlattice structures composed of three-dimensionally epitaxial PbTiO3 and PLT thin films have been successfully grown on SrTiO3 substrates by metalorganic chemical vapor deposition. The modulation structures were confirmed by θ-2θ XRD, and the excellent in-plane orientational relationship between the superlattice film and the substrate by (100), (110), and (111)-pole figures. The φ-scans through the (110) and (111) reflections were used as additional evidence for three-dimensional epitaxy. The substrate dependence of the epitaxial orientation of PLT and PbTiO3 single-layered thin films was investigated. PbTiO3 thin films with very high crystalline perfection can be successfully grown on KTaO3 substrates.

The diffusion coefficient of sodium, 22 Na, and silver, 110 Ag, and electrical conductivity for sodium borate glasses (4–24 mol% Na 2 O) has been measured from 100°C to slightly below the glass transition temperature, T g . Unlike silicate glasses where the self-diffusion coefficient is much larger than the impurity diffusion coefficient, D Na and D Ag had close to the same magnitude in the sodium borate glasses. In some glasses, D Ag was slightly larger than D Na . Na 2 O-Ag 2 O-B 2 O 3 glasses show a relatively small mixed alkali effect, despite the significant mass difference between Ag(≈108) and Na(≈23). It is concluded that the mixed alkali effect is more dependent upon the difference in ionic radii rather than differences in mass.