Since the discovery of X rays by Roentgen in 1895, the ionizing radiation has been
extensively utilized in a variety of medical and industrial applications. And it has also
played crucial roles in development of modern sciences and technologies, as witnessed
by more than 60 Nobel Prize winners awarded for achievements in atomic sciences
and ionizing radiation-related researches.
Physics and engineering governing the applications of synchrotron radiation
is based on enormous achievements during more than one hundred years in
the filed of X-ray physics and technology. The contents of this book, starting
with the very general aspects of synchrotron radiation investigated, have
been developed by numerous scientist and experimentalist in this field during
the past 20 years. The readers are recommended to visit the websites of
major synchrotron facilities in the world, and update their knowledge of this
rapidly changing and progressing field.
Induction of p53 by the DNA damage and oncogene checkpoints.
In response to noxious stimuli, p53 and mdm2 are phosphorylated by the ataxia telangiectasia mutated (ATM) and related ATR serine/threonine kinases, as well as the immediated downstream checkpoint kinases, Chk1 and Chk2. This causes dissociation of p53 from mdm2, leading to increased p53 protein levels and transcription of genes leading to cell cycle arrest (p21Cip1/Waf1) or apoptosis (e.g., the proapoptotic Bcl-2 family members Noxa and Puma).
In the 1960s radiation therapy was considered an empirical, clinical discipline with a
relatively low probability of success. This situation has changed considerably during the
past 40 years.
Radiation therapy is based heavily on fields such as physics, mathematics, computer
science and radiation biology as well as electrical and mechanical engineering, making it
a truly interdisciplinary field, unparalleled by any other clinical discipline. Now radiation
therapy can be applied so safely, precisely and efficiently that the previously feared side
effects no longer play a role.
In this chapter, we will address the following questions: What are species? How do new species arise? What happens when newly formed species come together? Why do rates of speciation vary? Why do adaptive radiations occur?
After studying this chapter, you should be able to accomplish the following outcomes: Distinguish between matter, elements, and atoms; name the six elements that are basic to life; describe the structure of an atom; tell why an atom can have isotopes; give examples of how low levels and high levels of radiation can each be helpful;...
For otolaryngology–head and neck surgeons in training as
residents and fellows, it is a difficult task to keep up with
all of the advances in the basic and clinical sciences that
impact the medical and surgical practice of their specialty.
It is also pertinent to the practice of otolaryngology–head
and neck surgery for interested medical students and lecturers
in medical school faculties who teach students and
resident physicians to have a reference book that clearly
presents the basic principles.
The heat radiation from gas flaring greatly affects the surrounding
environment and particular crops planted within the vicinity of gas flare stations
(Abdulkareem and Odigure, 2002). It also has a devastating effect on microorganisms and
aquatic life. Heat radiation from gas flaring also causes an increase in heat waves hence
there is the possibility that habitants of Niger-Delta Area, where the gas flaring stations are
located will suffer heart stroke, heart attacks and other ailments aggravated by the heat
(Odigure et al., 2003).
Cerium, an element in the lanthanide series, has a number of
radioactive isotopes. Several of these are produced in abundance in
nuclear fission reactions associated with nuclear industry operations
or detonation of nuclear devices. This report summarizes our present
knowledge of the relevant physical, chemical, and biological properties
of radiocerium as a basis for establishing radiation protection guidelines.
“Advances in Prostate Cancer” is an addition to the InTech collection of three previous
books about prostate cancer and aims at providing a comprehensive overview of specific
aspects of the latest research and current knowledge relating to this tumor entity to
scientists and clinicians. For this purpose a series of research articles, clinical investigations
and reviews that deal with a wide range of relevant aspects pertinent to the epidemiology,
diagnosis, patient care, treatment and basic biology of prostate cancer were included.
The idea of this book originates from a series of lectures on “Detectors
Application in Medicine and Biology” that I was asked to give as part of
the Academic Training Program at CERN in 1995. In preparing the
series of lectures, I realized that I would be talking about detector
properties and the medical applications of these detectors to the scientists
and engineers who were their inventors.
The cellular damage due to the hypoxi/re-oxigenative stress may trigger the production of
free radicals with consequent destabilization of the cell membranes (Calandrella et al., 2010).
As a matter of fact literature data show that the ischemic insult at retinal level activates
iNOS which leads to the production of nitrogen oxide (Goldstein et al., 1995; Geyer et al.,
1995): this compound is cytotoxic at high concentration and causes lipid peroxidation (Crow
et al., 1996; Ullrich et al., 2000).
Intensity-modulated radiotherapy (IMRT) has widened
the horizons of radiation therapy due to its ability to
conformradiation dose distributions to complex tumor
target volumes while sparing nearby critical structures
as much as physically possible. IMRT has also led to
paradigm shifts in all elements of the chain of radiotherapy,
from treatment prescription over treatment
planning (“inverse” planning) to treatment delivery and
This Report addresses in considerable detail the consequences of
hot particles on and near the skin, in the eye, ear, respiratory system,
and gastrointestinal tract. Limits for exposures from hot particles are
recommended. If exposures are maintained below the recommended
limits, few, if any, deterministic biological effects are expected to be
observed, and those effects would be transient in nature. If effects
from a hot-particle exposure are observed, the result is an easily
treated medical condition involving an extraordinarily small stochastic
The relative biological effectiveness of radiations of different quality
is examined in detail in this report. The analyses were performed
by Scientific Committee 40 of the NCRP which is charged with the
responsibility for analysis and evaluation of radiobiological data
relevant to radiation protection recommendations.
This report is a follow-on to the previous report of Scientific Committee
40 on its evaluation of the effects of dose rate which was
published in 1980 as NCRP Report No.
In 1961 the NCRP issued NCRP Report No. 28, A Manual of
Radioactivity Procedures, which was published as the National Bureau
of Standards Handbook 80. The report came to be one of the definitive
works in the area of radioactivity measurements. As the development
of new techniques, procedures, and equipment made parts of the
Report obsolescent, the NCRP recognized the need to update and
extend the document.
Radiology is an essential component of dental diagnosis. Available
data clearly show that ionizing radiation, if delivered in sufficient
doses, may produce biological damage. However, it is not clear
that radiation in doses required for dental radiography presents
any risk. Neither is it clear that these small doses are free of risk.
This report has been prepared as a result of a request to the
National Council on Radiation Protedion and Measurements (NCRP)
from the Nuclear Regulatory Commission (NRC). In recent years,
nuclear utilities have identified the potential for a limited number
of employees to come in contact with microscopic particles that are
radioactive. These particles have been given the generic name, independent
of their source and particular chemical and radioactive content,
of "hot particles."
Only a small portion of the energy radiated by the sun into space strikes the
earth, one part in two billion. Yet this amount of energy is enormous. For
instance, everyday enough energy strikes the United States to supply the
nation’s energy needs one and a half years!
Where does all the energy go? About 15 percent of the sun’s energy that hits the
earth is reflected back into space. Another 30 percent is used to evaporate water,
which lifted into the atmosphere, produces rainfall. Solar energy is also absorbed
by plants, the land, and the oceans. The rest...
Shielding gloves and sleeves containing up to 0.33 mmPb are manufactured.
Like aprons, they are ineffective shields against most radiations other than
electrons (beta particles) and low energy scattered X rays.
Wearing the gloves reduces dexterity and consequently, if used inappropri-
ately, will result in significant hand doses and greater body doses by
prolonging the exposure.
The sleeves are flexible and, when used as local shielding, provide good
cover for the extremities.