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1.
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。  相似文献   

2.
白琦锋  王文华  袁涛 《生态学杂志》2012,31(7):1855-1861
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。  相似文献   

3.
<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  相似文献   

4.
同步辐射方法在生命科学研究中有着十分重要的应用。上海光源是我国建造的第一个第三代同步辐射装置,本文结合上海光源首批建造的光束线站,介绍了几类同步辐射实验方法在生命科学中的应用。  相似文献   

5.
上海同步辐射装置线站概念设计研讨会暨用户筹备会于1998年12月28日至29日在上海嘉定举行。此次会议由上海同步辐射装置工程指挥部主办、中国科学院上海原子核研究所具体承办,以方守贤院士为主任、冼鼎昌院士为副主任的上海同步辐射装置(SSRF)科学技术委...  相似文献   

6.
夏星  杨建军 《生态学杂志》2019,30(1):348-358
铁氧化物在土壤中广泛赋存,因其比表面积大,对重金属具有很强的吸附固定能力,深刻影响着土壤重金属的形态转化过程.因此,研究土壤铁氧化物对重金属的固定机制,对于深入理解重金属在土壤系统中的环境化学行为以及评估污染土壤重金属生物有效性具有重要意义.然而,采用传统的吸附模型和化学提取法研究土壤铁氧化物固定重金属的机制具有明显的局限性,无法从分子水平上阐明其固定机制.同步辐射技术在环境土壤学的应用显著推进了在分子水平上认识土壤铁氧化物吸附重金属及其受典型环境因子影响的分子机制.本文主要从同步辐射技术的发展历程、模拟系统和实际土壤系统中铁氧化物在多种因素影响下对重金属固定的分子机制等方面进行了综述,同时对同步辐射技术的未来发展趋势及其在该研究领域的应用进行了展望.  相似文献   

7.
张智印  陶冶 《生命科学》2011,(7):714-722
同步辐射圆二色谱与普通圆二色谱相比,特点在于向真空紫外波段(〈200nm)拓展,以及同步辐射所提供的高强度紫外和真空紫外光源。糖的圆二色谱结构主要在200nm以下。蛋白质和核酸在200nm以下的真空紫外范围,也具有丰富的光谱结构。因此向真空紫外拓展,伴随新的电子跃迁,对应新的光谱结构,包含更丰富的结构信息,确定的结构种类就越多和越精确。同步辐射高强度的真空紫外光源,是获得高质量真空紫外圆二色谱数据的保证,为糖及糖蛋白、蛋白质和核酸研究提供了溶液中结构探测新的实验方法。综述同步辐射圆二色谱特点及其在结构生物学中的应用,以及新发展的蛋白质圆二色谱数据库(PCDDB)。介绍已对外开放的北京同步辐射实验室同步辐射圆二色谱探测,及其在蛋白质、糖和核酸研究中的应用,以及基于微流控混合芯片的亚毫秒动态探测发展。  相似文献   

8.
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。  相似文献   

9.
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。  相似文献   

10.
近年来,各种X射线三维无损成像技术在古生物学领域的应用越来越广泛。但是,不同的X射线三维无损成像技术针对不同保存类型和尺寸的化石标本在成像效果上各有利弊。本文以埃迪卡拉纪陡山沱组磷酸盐化的动物胚胎化石为研究对象,将目前应用最广的两种X射线三维无损成像方法,即基于实验室X光源的吸收衬度显微断层成像技术和基于同步辐射光源的相位衬度显微断层成像技术进行了对比分析。通过对两种技术的原理、效率、空间分辨率和图像衬度的对比,认为基于同步辐射光源的相位衬度显微断层成像技术是目前对于均一矿化的微体化石最佳的三维无损成像解决方案。  相似文献   

11.
红外成像技术在生命科学中的应用   总被引:2,自引:0,他引:2  
红外成像技术是利用物体自身各部分对红外热辐射的差异把红外辐射图像转换为可视图像的技术.对红外成像技术历史进行了简单介绍,对远红外成像技术在生命科学包括医学、植物、动物及农业中的应用进行了综述,并对红外成像技术在生命科学中的应用作了展望.  相似文献   

12.
Research at the European Synchrotron Radiation Facility medical beamline.   总被引:3,自引:0,他引:3  
The application of synchrotron radiation in medical research has become a mature field of research at synchrotron facilities worldwide. In the relatively short time that synchrotrons have been available to the scientific community, their characteristic beams of UV and X-ray radiation have been applied to virtually all areas of medical science which use ionizing radiation. The ability to tune intense monochromatic beams over wide energy ranges differentiates these sources from standard clinical and research tools. At the European Synchrotron Radiation Facility (Grenoble, France), a major research facility is operational on an advanced wiggler radiation beamport, ID17. The beamport is designed to carry out a broad range of research ranging from cell radiation biology to in vivo human studies. Medical imaging programs at ID17 include transvenous coronary angiography, computed tomography, mammography and bronchography. In addition, a major research program on microbeam radiation therapy is progressing. This paper will present a very brief overview of the beamline and the imaging and therapy programs.  相似文献   

13.
“Adaptive radiation” is an evocative metaphor for explosive evolutionary divergence, which for over 100 years has given a powerful heuristic to countless scientists working on all types of organisms at all phylogenetic levels. However, success has come at the price of making “adaptive radiation” so vague that it can no longer reflect the detailed results yielded by powerful new phylogeny‐based techniques that quantify continuous adaptive radiation variables such as speciation rate, phylogenetic tree shape, and morphological diversity. Attempts to shoehorn the results of these techniques into categorical “adaptive radiation: yes/no” schemes lead to reification, in which arbitrary quantitative thresholds are regarded as real. Our account of the life cycle of metaphors in science suggests that it is time to exchange the spent metaphor for new concepts that better represent the full range of diversity, disparity, and speciation rate across all of life.  相似文献   

14.
AimTo assess the role of the young radiation oncologist in the context of important recent advancements in the field of radiation oncology, and to explore new perspectives and competencies of the young radiation oncologist.BackgroundRadiation oncology is a field that has rapidly advanced over the last century. It holds a rich tradition of clinical care and evidence-based practice, and more recently has advanced with revolutionary innovations in technology and computer science, as well as pharmacology and molecular biology.Materials and methodsSeveral young radiation oncologists from different countries evaluated the current status and future directions of radiation oncology.ResultsFor young radiation oncologists, it is important to reflect on the current practice and future directions of the specialty as it relates to the role of the radiation oncologist in the comprehensive management of cancer patients. Radiation oncologists are responsible for the radiation treatment provided to patients and its subsequent impact on patients’ quality of life. Young radiation oncologists must proactively master new clinical, biological and technical information, as well as lead radiation oncology teams consisting of physicists, dosimetrists, nurses and technicians.ConclusionsThe role of the young radiation oncologist in the field of oncology should be proactive in developing new competencies. Above all, it is important to remember that we are dealing with the family members and loved ones of many individuals during the most difficult part of their lives.  相似文献   

15.
The new multipurpose infrared (IR) beamlineat the electron storage ring BESSY IIprovides highly brilliant infrared radiation forstructural and time resolved studies in thebiological and material science. With this facility newresearch possibilities at BESSY are madeavailable to the scientific community.  相似文献   

16.
The NASA Space Radiation Laboratory (NSRL) located at Brookhaven National Laboratory (BNL) is a center for space radiation research in both the life and physical sciences. BNL is a multidisciplinary research facility operated for the Office of Science of the US Department of Energy (DOE). The BNL scientific research portfolio supports a large and diverse science and technology program including research in nuclear and high-energy physics, material science, chemistry, biology, medial science, and nuclear safeguards and security. NSRL, in operation since July 2003, is an accelerator-based facility which provides particle beams for radiobiology and physics studies (Lowenstein in Phys Med 17(supplement 1):26–29 2001). The program focus is to measure the risks and to ameliorate the effects of radiation encountered in space, both in low earth orbit and extended missions beyond the earth. The particle beams are produced by the Booster synchrotron, an accelerator that makes up part of the injector sequence of the DOE nuclear physics program’s Relativistic Heavy Ion Collider. Ion species from protons to gold are presently available, at energies ranging from <100 to >1,000 MeV/n. The NSRL facility has recently brought into operation the ability to rapidly switch species and beam energy to supply a varied spectrum onto a given specimen. A summary of past operation performance, plans for future operations and recent and planned hardware upgrades will be described. Work performed under the auspices of the auspices of the US National Aeronautics and Space Administration and the US Department of Energy.  相似文献   

17.
Molecular imaging is an evolving science that is concerned with the development of novel imaging probes and biomarkers that can be used to non-invasively image molecular and cellular processes. This special issue approaches molecular imaging in the context of radiation research, focusing on biomarkers and imaging methods that provide measurable signals that can assist in the quantification of radiation-induced effects of living systems at the physical, chemical and biological levels. The potential to image molecular changes in response to a radiation insult opens new and exciting opportunities for a more profound understanding of radiation biology, with the possibility of translation of these techniques to radiotherapy practice. This special issue brings together 14 reviews dedicated to the use of molecular imaging in the field of radiation research. The initial three reviews are introductory overviews of the key molecular imaging modalities: magnetic resonance, nuclear and optical. This is followed by 11 reviews each focusing on a specialist area within the field of radiation research. These include: hypoxia and perfusion, tissue metabolism, normal tissue injury, cell death and viability, receptor targeting and nanotechnology, reporter genes, reactive oxygen species (ROS), and biological dosimetry. Over the preceding decade, molecular imaging brought significant new advances to our understanding of every area of radiation biology. This special issue shows us these advances and points to the vibrant future of our field armed with these new capabilities.  相似文献   

18.
Equipment that generates microwave radiation (MWR) spanning the frequency range of 300 MHz–100 GHz is becoming more common. While MWR lacks sufficient energy to break chemical bonds, the disagreement as to whether MWR exposure is detrimental to cellular dysfunction may be difficult to clarify using complex systems such as whole animals, cells, or cell extracts. Recently, the high frequency range of terahertz (THz) radiation has been explored and sources of radiation and its detectors have been developed. THz radiation is associated with the frequency interval from 100 GHz to 20 THz and constitutes the next frontier in imaging science and technology. In the present study, we investigated the effect of radiation in the low frequency THz range (100 GHz) on two defined molecular interactions. First, the interaction of soluble or immobilized calf alkaline phosphatase with the substrate p‐nitrophenylphosphate and second, the interaction between an antibody (mouse monoclonal anti‐DNP) and its antigen (DNP). Irradiation of enzyme either prior to addition of substrate or during the enzymatic reaction resulted in small but significant reductions in enzyme activity. These differences were not observed if the enzyme had previously been immobilized onto plastic microwells. Exposure of immobilized antigen to radiation did not influence the ability of the antigen to interact with antibody. However, irradiation appeared to decrease the stability of previously formed antigen–antibody complexes. Our data suggest that 100 GHz radiation can induce small but statistically significant alterations in the characteristics of these two types of biomolecular interactions. Bioelectromagnetics 30:167–175, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   

19.
Life science research in space was started in Europe with the first Biostack experiment flown onboard Apollo 16 in 1972. Biostack was designed to investigate the biological effects of single heavy ions of cosmic radiation. Among several undertakings towards this goal, the Biostack achieved the highest precision in the determination of the spatial correlation of the observed biological response of single test organisms to the passage of single heavy ions, which is the mandatory requirement. It also provided information on the influence of additional spaceflight factors, such as microgravity, on radiation effects and measurements of the spectrum of charge and energy of the cosmic radiation. The experiment was performed as an international cooperation effort. This report gives a summary of the biological data accumulated in this and the follow-on experiments of the Biostack program.Invited paper presented at the International Symposium on Heavy Ion Research: Space, Radiation Protection and Therapy, Sophia-Antipolis, France, 21–24 March 1994  相似文献   

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