同步辐射在生命科学中的应用──兼谈北京同步辐射装置（BSRF）

简要叙述了同步辐射在生命科学中的应用领域和方法,介绍北京同步辐射装置（ＢＳＲＦ）可以用于生命科学研究的实验站及业已开展的工作。     

同步辐射在显微CT中的应用

计算机X射线断层成像技术（CT）是利用X射线的穿透能力对物体进行扫描,所得信号经过反投影的算法而得到物体二维分布的一种成像方法,已经在医学诊断、工业探伤等领域广泛应用。但是由于实验室光源的低通量,光源点大小及其单色性等限制了其向高分辨发展,通常其分辨率在0．5mm左右。利用微焦点X射线源作为光源的显微CT分辨率可以达到微米量级,但是由于其光通量低且为非单色光,对不同样品有不同程度的束线硬化,影响了其真实分辨率。同步辐射作为一种新兴的光源有高亮度、高光子通量、高准直性、高极化性、高相干性及宽的频谱范围的特点,配合高分辨的X射线探测器,可以发展同步辐射显微CT,其分辨率可达10μm以下。利用同步辐射的高空间相干性开展位相衬度显微CT的研究,对低吸收物质也可以清晰三维成像。新建的上海光源的X射线成像及生物医学应用线站开展了三维显微CT方面的研究,经过初步试验,得到了较好的结果。     

同步辐射在植物科学研究中的应用

同步辐射是一种新型的光源,逐步被广泛应用于物理、化学、材料以及生命科学等研究领域。本文简单介绍了同步辐射在植物科学领域的应用成果。     

同步辐射X-ray光源在生物学研究中的应用与进展

20世纪七十年代以来,同步辐射装置经历了三个迅速发展阶段,现在,第四代X-ray自由电子激光线站已经建成。同步辐射光源已经成为生命科学、医学、化学、物理学、材料科学等学科领域最先进的实验设施,具有广泛而重要的应用前景。本文概述了同步辐射X-ray光源的特性,介绍了同步辐射X-ray光源在生物学研究中新的应用和进展。     

稀土元素在生命科学中的应用

稀土元素在生命科学中的应用蒋宇扬，张成刚，蔺继尚（中国科学院沈阳应用生态研究所，１１００１５）稀土元素又称稀土金属（简称ＲＥ）是指元素周期表中皿Ｂ族的斓系元素（镧、铈、镨、钕、钷、钐、、钆、铽、镐、钬、铒、铥、镜、锗）和抗与记。除抗外其它１６个元素化...     

磷光分析法在生命科学中的应用新进展

本文介绍了近年来磷光分析法在氨基酸,DNA和蛋白质研究中的应用,以及磷光分析法与其它分析技术相结合的研究进展。     

DNA芯片及其在生命科学中的应用

对DNA芯片的发生、发展、技术特点及在生命科学中的应用作了回顾,结果表明DNA芯片通过DNA或RNA样品与阵列的的杂交,可用于基因测序、基因表达、新基因的发现、突变的检测等等领域,虽然DNA芯片目前存在着不足和缺陷,但它正成为基因组和后基因组研究的重要工具.     

上海光源成功申办2012年同步辐射生物医学应用(MASR2012)国际会议

<正>2010年2月15～19日同步辐射生物医学应用国际会议在澳大利亚墨尔本召开,会议内容涵盖了世界主要同步辐射设施生物医学应用线站建设新近展、新的X-射线成像方法学研究以及众多基于同步辐射光的     

转基因小鼠在现代生命科学中的应用

随着分子生物学的发展,转基因技术取得了巨大的进步,并且在现代生命科学中得到了广泛的应用.针对转基因技术在生物医学研究领域中的重要作用,结合近年来转基因技术及转基因动物的研究成果,着重介绍转基因小鼠的发展,转基因的方法及在医学中的应用,并对转基因小鼠在现代生命科学中的应用前景进行了展望.     

Contact microscopy with synchrotron radiation

Soft X-ray contact microscopy with synchrotron radiation offers the biologist, and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM, or SEM methods (i.e., hydrated samples, samples easily damaged by an electron beam, electron-dense samples, thick specimens, unstained, low-contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash X-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of X-ray wavelengths or specific individual wavelengths that optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of X-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples.     

Aluminum site structure in serum transferrin and lactoferrin revealed by synchrotron radiation X-ray spectroscopy

The Al site structure of serum transferrin and lactoferrin is investigated using X-ray absorption near edge structure (XANES) spectroscopy. Al K-edge spectra in the mono- and dialuminum forms of the proteins have been recorded for the first time. Our results show that the aluminium ion is hexa-coordinated in an octahedral-like symmetry and that the monoaluminum form, where only the C-terminal binding site is saturated, has an increased structural distortion around the metal site.     

同步辐射技术在环境污染监测及生态毒理研究中的应用

随着环境问题的日趋严重,其研究也愈加深入,更多的高新技术也应用到该领域中。同步辐射是电子以接近光速的速度作圆周运动或蛇形运动,在改变运动方向时,沿着运动轨道的切线方向发出的电磁辐射,可在宽广的能量区域中利用高亮度、性能优越的光。本文综述了同步辐射技术在水体、大气和极地环境的污染监测中的作用,同时总结了其在有机化合物、典型重金属元素生态毒性研究中的应用,并进一步展望了该技术在环境领域的应用前景。     

A synchrotron radiation X-ray diffraction study of the crystallinity of tendon fibres

The equatorial diffraction pattern of tendon collagen fibres was measured during short successive exposures at different lengths using a double focusing X-ray synchrotron radiation camera with film and with an area detector. Similarly, patterns from thin fibres from premature rats were recorded. The patterns unambiguously illustrate the relationship between fibre crystallinity and the age of the animal. Further, the results indicate that in the initial part of the linear region of the stiffness-versus-length curve, the collagen fibres are characterized by a quasihexagonal arrangement of collagen molecules, whereas at the end of this region, the molecular arrangement becomes hexagonal.     

Data issues in the life sciences

We review technical and sociological issues facing the Life Sciences as they transform into more data-centric disciplines - the "Big New Biology". Three major challenges are: 1) lack of comprehensive standards; 2) lack of incentives for individual scientists to share data; 3) lack of appropriate infrastructure and support. Technological advances with standards, bandwidth, distributed computing, exemplar successes, and a strong presence in the emerging world of Linked Open Data are sufficient to conclude that technical issues will be overcome in the foreseeable future. While motivated to have a shared open infrastructure and data pool, and pressured by funding agencies in move in this direction, the sociological issues determine progress. Major sociological issues include our lack of understanding of the heterogeneous data cultures within Life Sciences, and the impediments to progress include a lack of incentives to build appropriate infrastructures into projects and institutions or to encourage scientists to make data openly available.     

Biological trace-element measurements using synchrotron radiation

The feasibility of performing X-ray fluorescence trace-element determinations at concentrations substantially below the ppm level for biological materials is demonstrated. Conditions for achieving optimum sensitivity were ascertained. Results achieved for five standard reference materials were, in most cases, in excellent agreement with listed values. Minimum detectable limits of 20 ppb were measured for most elements.     

Structure and growth of ultrasmall protein microcrystals by synchrotron radiation: II. microGISAX and microscopy of lysozyme

The early steps of growth and nucleation of the lysozyme microcrystals by classical and nanotemplate-based hanging vapor diffusion methods are studied using microGISAXS at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Out-of-plane cuts in the Yoneda regions of the 2D scattering profiles point to the detection of ultrasmall lysozyme crystals by microGISAXS quite before than by light microscopy. Furthermore lysozyme crystal formation occurs quite earlier with the nanotemplate than with the classical method. Our data are compatible with two distinct modes of crystal nucleation and growth for P450sc and lysozyme.     

Synchrotron radiation in life sciences

Synchrotron Radiation (SR) presents itself as a "play-ground" with a large range of methods and techniques suitable to unveil the mysteries of life. Here we attempt to present a few of these methods that complement those employed in the home laboratory. SR diffraction, spectroscopy and imaging methods relevant to the atomic structure determination and characterization of the properties and function of chemical compounds and macromolecules of biological relevance, are introduced.     

Prospects for microcomputerized-tomography using synchrotron radiation

A microversion of a computerized tomograph (CT) is described, in which the object is subjected to a successive series of translations with rotation by a small angle in between. The spatial resolution is determined by collimators and translation step lengths and is today, with clinical X-ray tube, of the order of 100 μm. The use of synchrotron radiation instead of X-ray tubes offers the advantages of much higher fluence rates, which can be used to diminish the exposure times from days to minutes or to increase the spatial resolution from 100 μm to about 1 μm. The possibility to receive monoenergetic photons of selectable energy makes it possible to avoid spectral hardening image artifacts, as well as to optimize the information sampling with regard to average absorbed dose or exposure time. Selectable photon energies are valuable also for tomochemistry applications.