Molecular Photobiology


Book Description

Molecular Photobiology: Inactivation and Recovery describes the deleterious photochemical reactions occurring in biological systems. This book is composed of 10 chapters that specifically tackle light interactions in the ultraviolet region of the spectrum resulting to damaged proteins and nucleic acids in living systems. This book deals first with the kinds of photochemical reactions that can occur and the possible effects of photochemistry on molecular, cellular, and organismal levels. The succeeding chapters highlight the principle of recovery mechanisms, wherein evidence shows that cells can repair their damaged genetic material, and thus recover from the otherwise inactivating effects of light. The remaining chapters are devoted to the comparison and contrast of some biological effects of ionizing radiation and those of ultraviolet radiation. This book is of value to molecular photobiologists, photochemists, biochemists, and radiation scientists and researchers.




Photobiology, Ionizing Radiations


Book Description

Comprehensive Biochemisty, Volume 27: Photobiology, Ionizing Radiations deals with the aspects of bioenergetics, immunochemistry, photobiology, and molecular phenomena that underlie the evolution of organisms. This book discusses the types of phototropic response, action spectra in the further ultraviolet, and structure and light-absorbing properties of the photoreceptor cells. The preliminary remarks on visual pigment structure, synopsis of extracted systems, oxidation of proteins, and effects of ultraviolet radiation and photoreactivation are also elaborated. This text likewise covers the chemical nature of photoreactivable damage, reversibility of potentiated flowering response, and primary reactions in algae and higher plants. This volume is beneficial to biochemists and specialists researching on ionizing radiations.




Photochemistry and Photobiology of Nucleic Acids


Book Description

Photochemistry and Photobiology of Nucleic Acids, Volume I: Chemistry covers the historical developments in the study of photobiology and photochemistry of nucleic acid components. This volume is divided into 12 chapters that deal with the isolation and characterization of ultraviolet photoproducts of pyrimidines. After briefly covering the concepts of photochemistry of nucleic acids, this volume goes on describing the UV-induced physical and chemical alterations in nucleic acid components, such as pyrimidines, purines, their nucleosides and nucleotides, and related compounds. Significant chap ...




Photobiology


Book Description

It is not always the case that the subject of a scientific book and its relevance to everyday li fe are so timely. Photobiology and its si ster subject Radiobiology are now a must for understanding the environment we live in and the impact light, ultraviolet light, and radiation have on all aspects of our life. Photobiology is a true interdisciplinary field. Photobiology research plays a direct role in diverse fields, and a glance at the topics of the symposia covered in this book by over 100 articles shows the breadth and depth of knowledge acquired in fundamental research and its impact on the major issues and applied problems the world is facing. Half a century of photobiology research brought about an understanding of the importance of light to life, both as a necessary source of energy and growth as weIl as its possible dangers. Research in photochemistry and photobiology led to the discoveries of ceIlular repair mechanisms of UV induced damages to DNA and this led to understanding of the effects of hazardous environmental chemieals and mutagenecity , and to the development of genetic engineering. This topic was given due emphasis in several symposia and chapters in this book.







Biophysics


Book Description

What is biophysics? As with all subjects which straddle traditional boundaries between fields, it eludes a precise definition. Furthermore, it is impossible to do biophysics without having a certain foundation of knowledge in biology, physics, physical chemistry, chemistry and biochemistry. One approach to a biophysics textbook would be to refer the student to the literature of these neighboring fields, and to leave the selection of the appropriate supplementary material up to the student. The editors of this volume are of the opinion that it is more useful and less time-consuming to present a selection of the supplementary knowledge, in concentrated form, together with the subject matter specific to biophysics. The reader will thus find in this book introductions to such subjects as the structure and function of the cell, the chemical structure of biogenic macromolecules, and even theoretical chemistry. What, indeed, is biophysics? Must we consider it to include physiology, electromedicine, radiation medicine, etc. ? The field has evolved continuously in recent years. Molecular understanding oflife processes has come more and more to the fore. Just as the field of molecular physics has developed to describe structures and processes in the realm of non-living systems, there has been a corresponding development of molecular biophysics.







Radiotherapy of Intraocular and Orbital Tumors


Book Description

Since the publication of the first edition of Radiotherapy of Intraocular and Orbital Tumors in 1993 the treatment programs for cure have changed from the dominance of surgical resection to the utilization of radiation therapy with preservation of the eye intact and preservation of vision. In 2002 about 2,300 primary eye tumors will be diagnosed in the United states, 75% of which will be choroidal melanomas, 20% retinoblastomas, and the remainder a wide variety of tumors - malignant lymphoma, rhabdomyosarcomas, liposarcomas, meningiomas, malignant fibrous histiocytomas, etc. Even so, the majority of malignant tumors of the eye are metastatic, primarily from cancers of the lung or breast. The impact of newer imaging studies, including computed tomography, magnetic resonance imaging, and ultrasound with and without contrast medium, have allowed for better tumor definition, more precise treatment techniques, and major improvement in local control, with preservation of the eye intact and excellent survival. The better histologic definition of the tumor has selected more appropriately the cases suitable for adjuvant chemotherapy particularly demonstrated by the combined integrated multimodal treatment of rhabdomyosarcoma without enucleation. Surgical techniques are now being reserved for biopsy and for treatment failures, a dramatic change in treatment approaches since 1993. The second edition by Sagerman and Alberti clearly demonstrates this major change in treatment. The volume explores the impact of diagnostic workup, the role of surgery, the role of external beam radiation therapy, the use of radioactive plaques, photocoagulation, cryotherapy, and other less major surgical procedures.




Electronic Irradiation of Foods


Book Description

Food irradiation, the use of ionizing radiation to destroy harmful biological organism in food, is a safe, proven process that has many useful applications. It has been endorsed by numerous health organizations and has now been approved for many applications by governments around the world. Electronic Irradiation of Foods describes all the key aspects of electron accelerator technology in detail. It emphasizes the physical science and technology aspects of food irradiation using machine sources of ionizing radiation. The book provides significant technical depth for interested workers and present descriptive, introductory material that should help demystify technology for businessmen to make informed choices regarding important investments decisions. Introductory chapters summarize the effects of ionizing radiation on biological organisms and the organic compounds comprising foods, and give an overview of the food irradiation process. Subsequent chapters cover the details of the electron beam and x-ray energy deposition, electron accelerator technologies, beam scanning systems, material handling systems, shielding design, and process control considerations. Important appendices cover radiation dosimetry, induced radioactivity, and ozone generation.




Non-ionizing Radiation Protection


Book Description

A comprehensive review of non-ionizing radiation and its public health and environmental risks, for researchers, policy makers, and laymen This book explains the characteristics of all forms of electromagnetic non-ionizing radiation (NIR) and analyzes the relationship between exposure and its biological effects, as well as the known dose-response relationships associated with each. Taking a uniquely holistic approach to the concept of health that builds upon the WHO definition to include not only absence of disease, but the physical, mental and social well-being of individuals and the population, it reviews established and potential risks and protections, along with regulatory issues associated with each. The risks to public health of NIR, whether in the form of UV light, radio waves from wireless devices, or electric and magnetic fields associated with electrical power systems, is currently a cause of great concern among members of the public and lawmakers. But in order to separate established science from speculation and make informed decisions about how to mitigate the risks of NIR and allocate precious resources, policymakers, manufacturers, and individuals need a comprehensive source of up-to-date information based on the current scientific evidence. Written by a team of experts in their fields, this book is that source. Among other things, it: Summarizes scientific findings on the safety of different forms of NIR and the rationale behind current standards Describes devices for monitoring NIR along with the established and potential hazards of each form Explores proper protections against UV light and lasers, RF radiation, ELF fields and other forms of NIR Discusses how to avoid injuries through occupational training or public awareness programs, and how to perform medical assessments in cases of suspected NIR injuries Considers how to decide whether or not to spend money on certain mitigation measures, based on cost-benefit analyses Offering expert reviews and analyses of the latest scientific findings and public policy issues concerning the risks to public health and the environment of NIR, Non-ionizing Radiation Protection is an indispensable source of information for manufacturers, government regulators, and regulatory agencies, as well as researchers, concerned laypersons, and students.