Download or read book X Ray Diffraction Imaging of Biological Cells written by Masayoshi Nakasako and published by Springer. This book was released on 2018-03-29 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the author describes the development of the experimental diffraction setup and structural analysis of non-crystalline particles from material science and biology. Recent advances in X-ray free electron laser (XFEL)-coherent X-ray diffraction imaging (CXDI) experiments allow for the structural analysis of non-crystalline particles to a resolution of 7 nm, and to a resolution of 20 nm for biological materials. Now XFEL-CXDI marks the dawn of a new era in structural analys of non-crystalline particles with dimensions larger than 100 nm, which was quite impossible in the 20th century. To conduct CXDI experiments in both synchrotron and XFEL facilities, the author has developed apparatuses, named KOTOBUKI-1 and TAKASAGO-6 for cryogenic diffraction experiments on frozen-hydrated non-crystalline particles at around 66 K. At the synchrotron facility, cryogenic diffraction experiments dramatically reduce radiation damage of specimen particles and allow tomography CXDI experiments. In addition, in XFEL experiments, non-crystalline particles scattered on thin support membranes and flash-cooled can be used to efficiently increase the rate of XFEL pulses. The rate, which depends on the number density of scattered particles and the size of X-ray beams, is currently 20-90%, probably the world record in XFEL-CXDI experiments. The experiment setups and results are introduced in this book. The author has also developed software suitable for efficiently processing of diffraction patterns and retrieving electron density maps of specimen particles based on the diffraction theory used in CXDI.

Download or read book Multiscale X Ray Analysis of Biological Cells and Tissues by Scanning Diffraction and Coherent Imaging written by Jan-David Nicolas and published by Göttingen University Press. This book was released on 2019 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the intricate details of muscle contraction has a long-standing tradition in biophysical research. X-ray diffraction has been one of the key techniques to resolve the nanometer-sized molecular machinery involved in force generation. Modern, powerful X-ray sources now provide billions of X-ray photons in time intervals as short as microseconds, enabling fast time-resolved experiments that shed further light on the complex relationship between muscle structure and function. Another approach harnesses this power by repeatedly performing such an experiment at different locations in a sample. With millions of repeated exposures in a single experiment, X-ray diffraction can seamlessly be turned into a raster imaging method, neatly combining real- and reciprocal space information. This thesis has focused on the advancement of this scanning scheme and its application to soft biological tissue, in particular muscle tissue. Special emphasis was placed on the extraction of meaningful, quantitative structural parameters such as the interfilament distance of the actomyosin lattice in cardiac muscle. The method was further adapted to image biological samples on a range of scales, from isolated cells to millimeter-sized tissue sections. Due to the ‘photon-hungry’ nature of the technique, its full potential is often exploited in combination with full-field imaging techniques. From the vast set of microscopic tools available, coherent full-field X-ray imaging has proven to be particularly useful. This multimodal approach allows to correlate two- and three-dimensional images of cells and tissue with diffraction maps of structure parameters. With the set of tools developed in this thesis, scanning X-ray diffraction can now be efficiently used for the structural analysis of soft biological tissues with overarching future applications in biophysical and biomedical research.

Download or read book Multiscale X Ray Analysis of Biological Cells and Tissues by Scanning Diffraction and Coherent Imaging written by Jan-David Nicolas and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The past 70 years of muscle research have profoundly shaped our current understanding of the structure and function of muscle. X-ray diffraction became a key method in its structural analysis and yielded valuable insights into the molecular arrangement of the contraction apparatus. This work employs an extension of the X-ray diffraction methodology, scanning X-ray diffraction, for structural imaging of biological cells and tissue. With this technique periodicites in a structure on the order of several nanometers can be detected and, by raster scanning of the X-ray beam over the sample, imag...

Download or read book A Study on New Approaches in Coherent X ray Microscopy of Biological Specimens written by Klaus Giewekemeyer and published by Universitätsverlag Göttingen. This book was released on 2011 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of coherent x rays for microscopic imaging has seen a rapid and ongoing development within the past decade, driven by an increasing availability of highly brilliant and coherent sources worldwide. Accordingly, novel methods have been developed, which replace the microscope‘s objective lens by a numerical reconstruction scheme. The aim of the present work is to study how very recent experimental and algorithmic developments in the field can be implemented towards a highly sensitive and fully quantitative microscopy method for imaging of biological cells. To this end, different experimental approaches are studied, based on coherent far-field as well as near-field diffraction. At first, an application of the novel ptychographic imaging method to single biological cells is presented. In particular, it is demonstrated how weakly scattering biological specimens can be imaged with fully quantitative density contrast. Alongside, a sueccessful extension of the method towards soft x-ray energies is described.In the second part of the work it is shown how x-ray waveguides can be used as a point source for propagation-based microscopy of single cells in the hard x-ray regime. The specifically devised iterative reconstruction scheme allows for full quantitativity and high sensitivity and thus enables an application to single biological cells. The work contains a thorough introduction into the x-ray optical methods applied and aims at a useful and self-contained overview on aspects of signal and Fourier theory relevant for the used numerical propagation schemes.

Download or read book Coherent X ray diffractive imaging on the single cell level of microbial samples written by Robin Niklas Wilke and published by Göttingen University Press. This book was released on 2015 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its first experimental demonstration in 1999, Coherent X-Ray Diffractive Imaging has become one of the most promising high resolution X-Ray imaging techniques using coherent radiation produced by brilliant synchrotron storage rings. The ability to directly invert diffraction data with the help of advanced algorithms has paved the way for microscopic investigations and wave-field analyses on the spatial scale of nanometres without the need for inefficient imaging lenses. X-Ray phase contrast which is a measure of the electron density is an important contrast mode of soft biological specimens. For the case of many dominant elements of soft biological matter, the electron density can be converted into an effective mass density offering a unique quantitative information channel which may shed light on important questions such as DNA compaction in the bacterial nucleoid through ‚weighing with light‘. In this work X-Ray phase contrast maps have been obtained from different biological samples by exploring different methods. In particular, the techniques Ptychography and Waveguide-Holographic-Imaging have been used to obtain twodimensional and three-dimensional mass density maps on the single-cell-level of freeze-dried cells of the bacteria Deinococcus radiodurans, Bacillus subtilis and Bacillus thuringiensis allowing, for instance, to estimate the dry weight of the bacterial genome in a near native state. On top of this, reciprocal space information from coherent small angle X-Ray scattering (cellular Nano-Diffraction) of the fine structure of the bacterial cells has been recorded in a synergistic manner and has been analysed down to a resolution of about 2.3/nm exceeding current limits of direct imaging approaches. Furthermore, the dynamic range of present detector technology being one of the major limiting factors of ptychographic phasing of farfield diffraction data has been significantly increased. Overcoming this problem for the case of the very intense X-Ray beam produced by Kirkpatrick-Baez mirrors has been explored by using semi-transparent central stops.

Download or read book Investigating Cellular Nanoscale with X rays written by Clément Hémonnot and published by Göttingen University Press. This book was released on 2016 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advances and technical improvements of X-ray imaging techniques, taking advantage of X-ray focussing optics and high intensity synchrotron sources, nowadays allow for the use of X-rays to probe the cellular nanoscale. Importantly, X-rays permit thick samples to be imaged without sectioning or slicing. In this work, two macromolecules, namely keratin intermediate filament (IF) proteins and DNA, both essential components of cells, were studied by X-ray techniques. Keratin IF proteins make up an integral part of the cytoskeleton of epithelial cells and form a dense intracellular network of bundles. This network is built from monomers in a hierarchical fashion. Thus, the keratin structure formation spans a large range of length scales from a few nanometres (monomers) to micrometres (networks). Here, keratin was studied at three different scales: i) filaments, ii) bundles and iii) networks. Solution small-angle X-ray scattering revealed distinct structural and organisational characteristics of these highly charged polyelectrolyte filaments, such as increasing radius with increasing salt concentration and spatial accumulation of ions depending on the salt concentration. The results are quantified by employing advanced modelling of keratin IFs by a core cylinder fl anked with Gaussian chains. Scanning micro- diffraction was used to study keratin at the bundle scale. Very different morphologies of keratin bundles were observed at different salt conditions. At the network scale, new imaging approaches and analyses were applied to the study of whole cells. Ptychography and scanning X-ray nano-diffraction imaging were performed on the same cells, allowing for high resolution in real and reciprocal space, thereby revealing the internal structure of these networks. By using a fitting routine based on simulations of IFs packed on a hexagonal lattice, the radius of each fi lament and distance between fi laments were retrieved. In mammalian cells, each nucleus contains 2 nm-thick DNA double helices with a total length of about 2 m. The DNA strands are packed in a highly hierarchical manner into individual chromosomes. DNA was studied in intact cells by visible light microscopy and scanning X-ray nano-diffraction, unveiling the compaction und decompaction of DNA during the cell cycle. Thus, we obtained information on the aggregation state of the nuclear DNA at a real space resolution on the order of few hundreds nm. To exploit to the reciprocal space information, individual diffraction patterns were analysed according to a generalised Porod’s law at a resolution down to 10 nm. We were able to distinguish nucleoli, heterochromatin and euchromatin in the nuclei and follow the compaction and decompaction during the cell division cycle.

Download or read book X Ray Microscopy written by Ping-Chin Cheng and published by . This book was released on 1987-12-07 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an up-to-date reference for biologists. Virtually all manners of x-ray microscopy, e.g. shadow projection x-ray microscopy, x-ray contact imaging, scanning x-ray microscopy, and imaging x-ray microscopy, as well as related subjects such as diffraction imaging, microholography, various x-ray sources, and focusing elements are extensively discussed. For illustration, numerous biological x-ray micrographs, obtained by different imaging techniques, are included in a small atlas. This reference book concludes with an extensive bibliography on x-ray microscopy, insuring its usefulness for all scientists intending to apply this new and powerful tool to their research.

Download or read book Biological Imaging by Soft X ray Diffraction Microscopy written by and published by . This book was released on 2005 with total page 15346 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have used the method of x-ray diffraction microscopy to image the complex-valued exit wave of an intact and unstained yeast cell. The images of the freeze-dried cell, obtained by using 750-eV x-rays from different angular orientations, portray several of the cell's major internal components to 30-nm resolution. The good agreement among the independently recovered structures demonstrates the accuracy of the imaging technique. To obtain the best possible reconstructions, we have implemented procedures for handling noisy and incomplete diffraction data, and we propose a method for determining the reconstructed resolution. This work represents a previously uncharacterized application of x-ray diffraction microscopy to a specimen of this complexity and provides confidence in the feasibility of the ultimate goal of imaging biological specimens at 10-nm resolution in three dimensions.

Download or read book X ray Micro and Nano diffraction Imaging on Human Mesenchymal Stem Cells and Differentiated Cells written by Marten Bernhardt and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in hard x-ray optics, instrumentation and detection have made it possible to probe biological samples by combining diffraction with raster scanning, using step sizes on the order of cellular organelle dimensions and below. The data obtained from such experiments encode the local electron density in a 2D-diffraction pattern for each scan position and provide information down to molecular scales. In this way, scanning transmission x-ray microscopy (with full diffraction data) complements very well the repertoire of high resolution imaging techniques. However, the challenge is ...

Download or read book X ray Free Electron Lasers written by Sébastien Boutet and published by Springer. This book was released on 2018-12-27 with total page 479 pages. Available in PDF, EPUB and Kindle. Book excerpt: The timely volume describes recent discoveries and method developments that have revolutionized Structural Biology with the advent of X-ray Free Electron Lasers. It provides, for the first time, a comprehensive examination of this cutting-edge technology. It discusses of-the-moment topics such as growth and detection of nanocrystals, Sample Delivery Techniques for serial femtosecond crystallography, data collection methods at XFELs, and more. This book aims to provide the readers with an overview of the new methods that have been recently developed as well as a prospective on new methods under development. It highlights the most important and novel Structural Discoveries made recently with XFELS, contextualized with a big-picture discussion of future developments.

Download or read book Nanoscale Photonic Imaging written by Tim Salditt and published by Springer Nature. This book was released on 2020-06-09 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book, edited and authored by a team of world-leading researchers, provides a broad overview of advanced photonic methods for nanoscale visualization, as well as describing a range of fascinating in-depth studies. Introductory chapters cover the most relevant physics and basic methods that young researchers need to master in order to work effectively in the field of nanoscale photonic imaging, from physical first principles, to instrumentation, to mathematical foundations of imaging and data analysis. Subsequent chapters demonstrate how these cutting edge methods are applied to a variety of systems, including complex fluids and biomolecular systems, for visualizing their structure and dynamics, in space and on timescales extending over many orders of magnitude down to the femtosecond range. Progress in nanoscale photonic imaging in Göttingen has been the sum total of more than a decade of work by a wide range of scientists and mathematicians across disciplines, working together in a vibrant collaboration of a kind rarely matched. This volume presents the highlights of their research achievements and serves as a record of the unique and remarkable constellation of contributors, as well as looking ahead at the future prospects in this field. It will serve not only as a useful reference for experienced researchers but also as a valuable point of entry for newcomers.

Download or read book Optical Systems for Soft X Rays written by A.G. Michette and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: A fundamental problem in cell biology is the cause of aging. The solution to this problem has not yet been obtained because,(l) until recently, it was not possible to image living cells directly. The use of low-energy (soft) X rays has made such imaging possible, perhaps thereby allowing the aging process to be understood and possibly overcome (a result that may well generate further social, moral, and ethical problems). Fortun ately this is not the only aspect of cell biology amenable to soft X-ray imaging, and it is envisaged that many less controversial studies--such as investigations of the detailed differences between healthy and diseased or malignant cells (in their natural states) and processes of cell division and growth-will be made possible. The use of soft X rays is not limited to biological studies-many applications are possible in, for example, fusion research, materials science, and astronomy. Such studies have only recently begun in earnest because several difficulties had to be overcome, major among these being the lack (for some purposes) of sufficiently intense sources, and the technological difficulties associated with making efficient optical systems. As is well known, the advent of dedicated synchrotron radiation sources, in particular, has alleviated the first of these difficulties, not just for the soft X-ray region. It is the purpose of this book to consider progress in the second.

Download or read book Biological Soft X ray Contact Microscopy written by Geoffrey David Guttmann and published by . This book was released on 1989 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High resolution X ray Diffraction Microscopy of Specifically Labeled Yeast Cells written by and published by . This book was released on 2010 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the [alpha]-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.

Download or read book X ray Microscopy written by Chris Jacobsen and published by Cambridge University Press. This book was released on 2019-12-19 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by a pioneer in the field, this text provides a complete introduction to X-ray microscopy, providing all of the technical background required to use, understand and even develop X-ray microscopes. Starting from the basics of X-ray physics and focusing optics, it goes on to cover imaging theory, tomography, chemical and elemental analysis, lensless imaging, computational methods, instrumentation, radiation damage, and cryomicroscopy, and includes a survey of recent scientific applications. Designed as a 'one-stop' text, it provides a unified notation, and shows how computational methods in different areas are linked with one another. Including numerous derivations, and illustrated with dozens of examples throughout, this is an essential text for academics and practitioners across engineering, the physical sciences and the life sciences who use X-ray microscopy to analyze their specimens, as well as those taking courses in X-ray microscopy.

Download or read book Imaging Life written by Gary C. Howard and published by Oxford University Press. This book was released on 2014-07-30 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides an overview of a variety of approaches to biological image analysis, which allow for the study of living organisms at all levels of complexity and organization. These organisms range from individual macromolecules to subcellular and cellular volumes, tissues and microbial communities. Such a "systems biology" understanding of life requires the combination of a variety of imaging techniques, and with it an in-depth understanding of their respective strengths and limitations, as well as their intersection with other techniques. Howard, Brown, and Auer show us that the integration of these imaging techniques will allow us to overcome the reductionist approach to biology that dominated the twentieth century, which was aimed at examining the physical and chemical properties of life's constituents, one macromolecule at a time. However, while based on the laws of physics and chemistry, life is not simply a set of chemical reactions and physical forces; it features an exquisite spatiotemporal organization that allows an inconceivably large number of chemical processes to coexist, refined by billions of years of evolutionary experimentation. And yet, many fundamental questions remain largely unanswered; Imaging Life argues that we are just now beginning to address the spatiotemporal organizational component of living processes. "Imaging" is needed in order to reveal the spatiotemporal relationships between components, and thus to understand organizational guiding principles of living systems. Only through imaging will we be able to decipher the mechanisms and the marvelous organization that enable and sustain the mystery of life. Imaging Life shows us how biology is beginning to do just that.

Download or read book Biological Imaging by Soft X ray Diffraction Microscopy written by David Shapiro and published by . This book was released on 2004 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: