Abstract：
:A classical trajectory model has been used to predict total cross sections of single and double ionizing processes (including capture processes) for several ion-biological molecule collisional systems in the intermediate and high energy range. In this work, the systems studied are water, adenine or cytosine targets ionized by protons and alpha-particles with kinetic energies ranging from 25 keV amu(-1) to 3000 keV amu(-1). In our approach, we have combined several features of two classical methods namely the classical trajectory Monte Carlo (CTMC) and the classical over-barrier (COB) models. For the water target, our results are compared, for high kinetic energies of incident particles, to the available experimental and theoretical results, and reasonable agreement are generally observed especially for the single ionization (liberated electron moves freely after the collision) and the single capture (liberated electron captured by the projectile), both processes representing ionizing processes. Considering the double ionizing processes which have been largely less studied, the unique comparison concerns the double capture process for alpha+H(2)O collision for which we reproduce the experiment reasonably well. Finally, we present total cross sections of single and double ionizing processes for biological targets such as adenine and cytosine where no experimental results exist till now.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Abbas I,Champion C,Zarour B,Lasri B,Hanssen Jdoi
10.1088/0031-9155/53/4/N03subject
Has Abstractpub_date
2008-02-21 00:00:00pages
N41-51issue
4eissn
0031-9155issn
1361-6560pii
S0031-9155(08)50191-6journal_volume
53pub_type
杂志文章abstract：:Dental tomographic cone-beam x-ray imaging devices record truncated projections and reconstruct a region of interest (ROI) inside the head. Image reconstruction from the resulting local tomography data is an ill-posed inverse problem. A new Bayesian multiresolution method is proposed for local tomography reconstructio...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/52/22/008
更新日期：2007-11-21 00:00:00
abstract：:The most advanced delivery technique for proton radiotherapy is active spot scanning. So far, predominantly static targets have been treated with active spot scanning, since mobile targets in combination with dynamic treatment delivery can lead to interplay effects, causing inhomogeneous dose distributions. One way to...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/56/22/016
更新日期：2011-11-21 00:00:00
abstract：:Input functions required for positron emission tomography (PET) tracer kinetic modeling are often obtained from arterial blood. In some situations, using short-lived radiotracers, e.g. [(15)O]water, rapid sample handling is required. A method used at several facilities is to pump blood through a detector system at a c...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/53/2/003
更新日期：2008-01-21 00:00:00
abstract：:The objective of this work is to test analytical models to calculate the luminescence efficiency of Al(2)O(3):C optically stimulated luminescence detectors (OSLDs) exposed to heavy charged particles with energies relevant to space dosimetry and particle therapy. We used the track structure model to obtain an analytica...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/57/2/437
更新日期：2012-01-21 00:00:00
abstract：:The authors have developed an apparatus able to generate ID intensity-modulated beams, using only one moving absorber within the irradiation field. A procedure for deriving optimized absorber-speed profiles in order to produce the desired fluence/dose profiles has been suggested. Experimental tests show that the syste...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/40/2/002
更新日期：1995-02-01 00:00:00
abstract：:Fluorescence molecular tomography (FMT) is widely used in preclinical oncology research. FMT is the only imaging technique able to provide 3D distribution of fluorescent probes within thick highly scattering media. However, its integration into clinical medicine has been hampered by its low spatial resolution caused b...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/aaf96d
更新日期：2019-01-22 00:00:00
abstract：:We find the dose distribution that maximizes the tumour control probability (TCP) for a fixed mean tumour dose per fraction. We consider a heterogeneous tumour volume having a radiation response characterized by the linear quadratic model with heterogeneous radiosensitivity and repopulation rate that may vary in time....
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/49/3/005
更新日期：2004-02-07 00:00:00
abstract：:Recently, a new family of low-cost x-radiation detectors have been developed, based on semiconducting polymer diodes, which are easy to process, mechanically flexible, relatively inexpensive, and able to cover large areas. To test their potential for radiotherapy applications such as beam monitors or dosimeters, as an...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/58/13/4471
更新日期：2013-07-07 00:00:00
abstract：:The optical properties (absorption and scattering coefficients and the scattering anisotropy factor) were measured in vitro for cartilage, liver, lung, muscle, myocardium, skin, and tumour (colon adenocarcinoma CC 531) at 630, 632.8, 790, 850 and 1064 nm. Rabbits, rats, piglets, goats, and dogs were used to obtain the...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/42/11/017
更新日期：1997-11-01 00:00:00
abstract：:Treatment planning for proton tumor therapy requires a fast and accurate dose-calculation method. We have implemented a simplified Monte Carlo (SMC) method in the treatment planning system of the National Cancer Center Hospital East for the double-scattering beam delivery scheme. The SMC method takes into account the ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/55/12/018
更新日期：2010-06-21 00:00:00
abstract：:A number of heating sources are available for minimally invasive thermal therapy of tumours. The purpose of this work was to compare, theoretically, the heating characteristics of interstitial microwave, laser and ultrasound sources in three tissue sites: breast, brain and liver. Using a numerical method, the heating ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/43/12/011
更新日期：1998-12-01 00:00:00
abstract：:This work presents an improvement of the VIPARnd ('nd' stands for 'normoxic, double', or VIP) polymer gel dosimeter. The gel composition was altered by increasing the concentration of the monomeric components, N-vinylpyrrolidone (NVP) and N,N'-methylenebisacrylamide (MBA), in co-solvent solutions. The optimal composit...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/aa5089
更新日期：2017-02-07 00:00:00
abstract：:Contrast-enhanced ultrasound (US) imaging is potentially applicable to the investigation of vascular disorders of the testis. We investigated the ability of two automated computer algorithms to analyse contrast-enhanced pulse inversion US data in a rabbit model of unilateral testicular ischaemia and to correctly deter...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/51/14/010
更新日期：2006-07-21 00:00:00
abstract：:In modern radiotherapy the verification of complex treatments plans is often performed in inhomogeneous or even anthropomorphic phantoms. For dose verification small detectors are necessary and therefore alanine detectors are most suitable. Though the response of alanine for a wide range of clinical photon energies in...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/61/3/N70
更新日期：2016-02-07 00:00:00
abstract：:Assessment of radiation absorbed dose to internal organs of the body from the intake of radionuclides or, in the medical setting through the injection of radiopharmaceuticals, is generally performed based upon reference biokinetic models or patient imaging data, respectively. Biokinetic models estimate the time course...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/abc708
更新日期：2020-11-03 00:00:00
abstract：:This paper presents two methods for absorbed dose determination with ionization chambers at short distance from 60Co and 192Ir brachytherapy sources. The methods are modifications of the Bragg-Gray and large cavity principles given in the IAEA code of practice for high- and medium-energy photon beams. A non-uniformity...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/43/11/002
更新日期：1998-11-01 00:00:00
abstract：:Most existing spatiotemporal multi-dipole approaches for MEG/EEG source localization assume that the dipoles are active for the full time range being analysed. If the actual time range of activity of sources is significantly shorter than the time range being analysed, the detectability, localization and time-course de...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/51/10/004
更新日期：2006-05-21 00:00:00
abstract：:In stereotactic radiosurgery, a seven-irradiation film was used to define any discrepancy between the beam and target centres. A mathematical model based on the linac alignment and target set-up was developed to diagnose the discrepancies of the seven-irradiation film between the beam and simulation target centres. Fr...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/41/9/003
更新日期：1996-09-01 00:00:00
abstract：:This paper investigates the feasibility of a scanned cylindrical ultrasound system for producing uniform heating from the central to the superficial portions of the breast or localized heating within the breast at a specific location. The proposed system consists of plane ultrasound transducer(s) mounted on a scanned ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/51/3/005
更新日期：2006-02-07 00:00:00
abstract：:Radiomic features achieve promising results in cancer diagnosis, treatment response prediction, and survival prediction. Our goal is to compare the handcrafted (explicitly designed) and deep learning (DL)-based radiomic features extracted from pre-treatment diffusion-weighted magnetic resonance images (DWIs) for predi...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/ab7970
更新日期：2020-04-02 00:00:00
abstract：:Measurements have been made using an air sampler to measure airborne radioactivity produced during the routine handling of large activities of technetium-99m, iodine-125 and iodine-131. The results indicate that 99Tcm can be safely handled in environments without direct exhaust of the ventilated air but that 125I and ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/25/6/005
更新日期：1980-11-01 00:00:00
abstract：:In this note a technique is described for direct aperture optimization of components deliverable by a variable aperture collimator (VAC) for intensity-modulated radiation therapy. The first key result found was that, provided a large number of VAC components were selected for optimization, the resulting fluence profil...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/49/5/n02
更新日期：2004-03-07 00:00:00
abstract：:The aim of this paper is to determine the dosimetric impact of trace elements in human tissues for low-energy photon sources used in brachytherapy. Monte Carlo dose calculations were used to investigate the dosimetric effect of trace elements present in normal or cancerous human tissues. The effect of individual trace...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/57/11/3585
更新日期：2012-06-07 00:00:00
abstract：:In vitro dielectric properties of ageing porcine tissues were measured in the frequency range of 50 MHz-20 GHz, and the total combined uncertainties of the measurements were assessed. The results show statistically significant reduction with age in both permittivity and conductivity of 10 out of 15 measured tissues. A...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/54/2/004
更新日期：2009-01-21 00:00:00
abstract：:Quantification in cardiac mouse positron emission tomography (PET) imaging is limited by the imaging spatial resolution. Spillover of left ventricle (LV) myocardial activity into adjacent organs results in partial volume (PV) losses leading to underestimation of myocardial activity. A PV correction method was develope...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/57/13/4309
更新日期：2012-07-07 00:00:00
abstract：:Ultrasoft x-rays of 0.3-5 keV have provided a unique tool for the investigation of intracellular mechanisms of radiation action in biological organisms, including mammalian cells. However, their use presents unique practical problems in dosimetry and experimental design. Detailed interpretation of the biological resul...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/30/10/002
更新日期：1985-10-01 00:00:00
abstract：:The dependence of boron-dose enhancer (BDE) characteristics on dose protocol and 10B concentration was evaluated for BNCT using near-threshold 7Li(p,n)7Be direct neutrons. The treatable protocol depth (TPD) was utilized as an evaluation index. MCNP calculations were performed for near-threshold 7Li(p,n)7Be at a proton...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/50/1/013
更新日期：2005-01-07 00:00:00
abstract：:A method is described whereby, utilising a biocompatible magnetic glass-ceramic material, effective hysteresis heating in living tissue was accomplished. Initial experiments on mice showed that a significant heating effect can be obtained in the ceramic-impregnated regions. An analysis is also given for the projected ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/29/5/001
更新日期：1984-05-01 00:00:00
abstract：:Near-infrared fluorescence optical imaging has the unique opportunity of differentiating diseased lesions from normal lesions based upon environmentally indicated changes in the lifetime of a fluorescent imaging agent. In this paper, we demonstrate three-dimensional lifetime tomography using the gradient-based penalty...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/52/14/009
更新日期：2007-07-21 00:00:00
abstract：:In the field of regenerative medicine, there has been a growing interest in studying the combination of bone scaffolds and cells that can maximize newly formed bone. In-line phase-contrast x-ray tomography was used to image porous bone scaffolds (Skelite(©)), seeded with bone forming cells. This technique allows the q...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/61/9/N215
更新日期：2016-05-07 00:00:00
