光纤智能复合材料

对光纤型智能复合材料的工作原理，性能特点和应用前景作了介绍，并讨论了制造成型的技术问题。     

Prognostic factors of primary liver cancer

To investigate the prognostic factors of primary liver cancer (PLC) and improve the long-term results, 1,248 cases of PLC were analysed. Univariate analysis demonstrated that discovery approach, staging of PLC, original gamma-GPT, resection, radical resection, original AFP, tumor size, tumor number, and tumor capsule have very significant effects on prognosis of PLC (all P < 0.001); cirrhosis, HBsAg, local resection, and tumor embolus in portal vein were also significant difference (all P < 0.05); age, sex, original AFP, hepatitis, and differentiation of PLC cells were no significant difference (all P > 0.05). Multivariate analysis demonstrated that original gamma-GPT, radical resection, tumor size, and tumor number were the most significant prognostic factors (all P < 0.001). Some aspects improving long-term survival were discussed.     

金刚石光电导探测器研制及在软X光测量中的初步应用

介绍了我们自己设计制造的天然Ⅱａ型金刚石光导探测器的结构，原理，制造工艺，实验标定及其在ＩＣＦ实验中软Ｘ光测量中的应用等。     

Analysis of dinosaur samples by nuclear microscopy

Several dinosaur bone and eggshell fossil samples unearthed at different sites in China were analyzed by means of nuclear microscopy. Concentrations and distributions of elements such as Na, Mg, Al, P, S, Ca, Cr, Mn, Fe, Cu, Zn, As, Br, Sr, Y, Ce, Pb and U, etc. were obtained for each sample. The results of quantitative PIXE and RBS analyses show unusually high concentrations of U and Ce in several samples obtained from a period near the K-T boundary (between Cretaceous and Tertiary periods, 65 million years ago), suggesting that some form of environmental pollution could be the cause of dinosaur extinction.     

Designing the MPC105 PCI bridge/memory controller

The MPC105 peripheral component interconnection bridge/memory controller provides a platform-specification-compliant bridge between Power PC microprocessors and the PCI bus. With it, designers can create systems using peripherals already designed for a variety of standard PC interfaces. This bridge chip also integrates a secondary cache controller and high-performance memory controller that supports DRAM or synchronous DRAM and ROM or flash ROM     

Where should health services go: local authorities versus the NHS?

The Association of Metropolitan Authorities has recently proposed that responsibility for the NHS should pass from health authorities to local authorities. One of the fiercest debates at the outset of the NHS was whether the hospitals should be run by local authorities. In the end the minister for health, Aneurin Bevan, decided against local democracy and in favour of a national health service. His arguments included the fact that equality of treatment could not be guaranteed if facilities varied with local finances and that even the largest authorities were not big enough to pool risks and expertise. All these arguments still apply today, and the recent changes in community care provide an insight into how a market model of local authority control might work. The changes have been accompanied by a shift from public to private sector provision and the introduction of charges for services that the NHS once provided free. As important, the willingness and ability of local authorities to raise extra revenue from local taxes and charges affect the service they can provide, so leading to inequalities of provision. Local authorities have yet to make the case that they can preserve the fundamental principles and benefits of the NHS, including its reliance on central taxation and unified funding formulas.     

Comparison of protein adsorption isotherms and uptake rates in preparative cation-exchange materials

Adsorption isotherms and effective diffusivities of lysozyme in a set of six preparative cation-exchange stationary phases were determined from batch uptake data in a stirred vessel. Both a pore diffusion and a homogeneous diffusion model were used in estimating diffusivities, with the isotherms fitted to a non-Langmuirian analytical isotherm equation. The capacities inferred from the isotherms are found to be correlated with the surface area accessible to lysozyme, the effective surface concentrations obtained being in agreement with values measured by different methods in various non-chromatographic systems. The pore diffusivities show systematic trends with protein and salt concentration, and effects of pore size and connectivity are also evident. Some trends in the homogeneous diffusivities are quite different to those in the pore diffusivities, but these differences largely disappear when the homogeneous diffusivities are rescaled to account for adsorption equilibrium behavior. Additional information is required to elucidate further the mechanisms of coupled diffusion and adsorption in stationary phases.     

Experimental study of the interaction range and association rate of surface-attached cadherin 11

We describe a method allowing quantitative determination of the interaction range and association rate of individual surface-attached molecules. Spherical beads (1.4 micro(m) radius) were coated with recombinant outer domains of the newly described classical type II cadherin 11, a cell adhesion molecule. Beads were driven along cadherin-coated surfaces with a hydrodynamic force of approximately 1 pN, i.e., much less than the mechanical strength of many ligand-receptor bonds. Spheres displayed periods of slow motion interspersed with arrests of various duration. Particle position was monitored with 50 Hz frequency and 0.025 micro(m) accuracy. Nearly 1 million positions were recorded and processed. Comparison between experimental and computer-simulated trajectories suggested that velocity fluctuations might be related quantitatively to Brownian motion perpendicular to the surface. The expected amplitude of this motion was of order of 100 nm. Theoretical analysis of the relationship between sphere acceleration and velocity allowed simultaneous determination of the wall shear rate and van der Waals attraction between spheres and surface. The Hamaker constant was estimated at 2.9 x 10(-23) J. The frequency of bond formation was then determined as a function of sphere velocity. Experimental data were consistent with the view that the rate of association between a pair of adhesion molecules was approximately 1.2 x 10(-3) s-1 and the interaction range was approximately 10 nm. It is concluded that the presented methodology allows sensitive measurement of sphere-to-surface interactions (with approximately 10 fN sensitivity) as well as the effective range and rate of bond formation between individual adhesion molecules.