Hiroshi Watabe
Tohoku University, Cyclotron and Radioisotope Center, Faculty Member
<p>The relationships among Vt by Logan plot analysis, SUV at 30 min, radioactivity count by well counter, and AChE activity by fluorometric assay.</p
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ABSTRACT Positron emission tomography (PET) with [F-18]-FDG can display cancerous activity depending on glucose uptake. Consequently, different PET tracers with different metabolisms are needed for further indication. We have developed... more
ABSTRACT Positron emission tomography (PET) with [F-18]-FDG can display cancerous activity depending on glucose uptake. Consequently, different PET tracers with different metabolisms are needed for further indication. We have developed multifunctional PET agents by combining Zn-62(2+) ion with laserphyrin (R) and bisglycosylated 5,10,15,20-tetrakis (pentafluorophenyl)porphyrins (H(2)Glccis-2 and H(2)Glctrans-2), which can be easily synthesized and have a half-life of 9 h. Zn-62-Labeled chemicals were successfully detected as PET signals in vivo and showed PDT-induced cell death by photoirradiation.
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In nuclear medicine, the development of portable imaging devices that provide high imaging resolution and sensitivity, capable of imaging gamma rays with a wide energy range and multiple radioisotopes tracing capabilities, is so... more
In nuclear medicine, the development of portable imaging devices that provide high imaging resolution and sensitivity, capable of imaging gamma rays with a wide energy range and multiple radioisotopes tracing capabilities, is so important. These goals have been possible thanks to developing a compact Compton camera, a collimatorless detector coupled to compact silicon photomultiplier(SiPM) array, using scintillator crystal. In this study, the portable segmented GAGG:Ce scintillator-based Compton camera (CC) is optimized with the GATE, a Monte Carlo simulation toolkit based on Geant4, to maximize its performance for a wide range of gamma-ray energy (364–1000 keV). The geometrical parameters are selected as optimization parameters to investigate their effects on CC's performance, including imaging resolution and absolute detection efficiency (DE a ). The geometry parameters of CC include the planner area of scatterer and absorber detectors, their thicknesses, and the distance between them. The results for the energy range of 364–1000 keV show that the most important contributions to the spatial resolution and DE a of the camera are SAD (scatterer to absorber distance) and the scatterer area while changing absorber area (AA ) showed the most negligible impact. In the short SADs, imaging resolution and DE a are significantly affected by the detector's size and thickness. On the other hand, in the long SADs (&gt; 4 cm), both spatial resolution and DE a are significantly affected by the detector's area but less affected by the detector's thickness. Decreasing the scatterer's thickness and the absorber's size or thickness improves imaging resolution without significantly reducing DE a . The simulation study's findings presented here will provide valuable guidelines for researchers choosing a desired CC's design according to particular objectives, manufacturing limitations in scintillator growth, cost, etc.
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With the aim of providing critical nuclear data of primary knock-on atoms (PKAs) created from proton-induced spallation reactions, a new detection system was designed and dedicated to the PKA measurement that requires lower measurement... more
With the aim of providing critical nuclear data of primary knock-on atoms (PKAs) created from proton-induced spallation reactions, a new detection system was designed and dedicated to the PKA measurement that requires lower measurement threshold energies and superior mass resolution than the conventional experimental setups. Such requirements can be fulfilled by employing the TOF-E and dE-E methods, and this new PKA detection system, which consists of two fast timing detectors and one dE-E gas ionization detector. The design of the detectors and the experimental setup, along with the estimated system performed are briefly described in this paper.
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In our previous work, a cost-effective Compton camera (CC) using Ce doped Gd3(Al,Ga)5O12(Ce:GAGG) scintillator consisting of two detectors, scatterer (20.8 × 20.8 × 5 mm3) and absorber (41.7 × 41.7 × 10 mm3), was developed to image gamma... more
In our previous work, a cost-effective Compton camera (CC) using Ce doped Gd3(Al,Ga)5O12(Ce:GAGG) scintillator consisting of two detectors, scatterer (20.8 × 20.8 × 5 mm3) and absorber (41.7 × 41.7 × 10 mm3), was developed to image gamma rays having energy more than 511 keV. This study fabricated a newly developed CC with a larger scatterer and thinner absorber. The system consists of two detectors: a scatterer and an absorber of Ce:GAGG scintillator. The size of the scatterer and absorber is the same; a 40-mm × 40-mm × 5-mm array block consists of 40 × 40 pixels. The size of each scintillator pixel is 0.85 mm × 0.85 mm for both systems. Imaging experiments of Na-22 and Cs-137 point sources were performed to investigate the imaging capability of the new camera, and then the obtained data were compared to the previous CC. The current CC's absolute detection efficiency (DE a ) and photopeak detection efficiency (DE p ) are improved by 1.6 and 2 times greater than the previous one. At the same time, both systems' spatial and angular resolutions are almost the same value at 511 keV. The Compton camera module (CCMod) in GATE v9.0 was employed for Monte Carlo simulations to reproduce the experimental data showing a good agreement.
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The present work introduced a framework to investigate the effectiveness of proton boron fusion therapy (PBFT) at the cellular level. The framework consisted of a cell array generator program coupled with PHITS Monte Carlo package with a... more
The present work introduced a framework to investigate the effectiveness of proton boron fusion therapy (PBFT) at the cellular level. The framework consisted of a cell array generator program coupled with PHITS Monte Carlo package with a dedicated terminal-based code editor that was developed in this work. The framework enabled users to model large cell arrays with normal, all boron, and random boron filled cytoplasm, to investigate the underlying mechanism of PBFT. It was found that alpha particles and neutrons could be produced in absence of boron mainly because of nuclear reaction induced by proton interaction with 16O, 12C and 14N nuclei. The effectiveness of PBFT is highly dependent on the incident proton energy, source size, cell array size, buffer medium thickness layer, concentration and distribution of boron in the cell array. To quantitatively assess the effectiveness of PBFT, of the total energy deposition by alpha particle for different cases were determined. The number ...
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To evaluate tumor blood flow using 15O-water positron emission tomography (PET) in patients with non-small cell lung cancer (NSCLC) before and after chemotherapy with bevacizumab, and to investigate the effects of bevacizumab on tumor... more
To evaluate tumor blood flow using 15O-water positron emission tomography (PET) in patients with non-small cell lung cancer (NSCLC) before and after chemotherapy with bevacizumab, and to investigate the effects of bevacizumab on tumor blood flow changes and progression-free survival (PFS). Twelve patients with NSCLC were enrolled. Six patients underwent chemotherapy with bevacizumab and the other six without bevacizumab. 15O-water dynamic PET scans were performed within 1 week before the start of chemotherapy and within 1 week after the first day of chemotherapy. Tumor blood flow was analyzed quantitatively using a single one-tissue compartment model with the correction of pulmonary circulation blood volume and arterial blood volume via an image-derived input function. In the bevacizumab group, mean tumor blood flow was statistically significantly reduced post-chemotherapy (pre-chemotherapy 0.27 ± 0.14 mL/cm3/min, post-chemotherapy 0.18 ± 0.12 mL/cm3/min). In the no bevacizumab grou...
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Image statistics are frequently used for functional and molecular imaging research in which images from a patient group with a specific diagnosis are compared with images from a healthy control group who have been matched for demographic... more
Image statistics are frequently used for functional and molecular imaging research in which images from a patient group with a specific diagnosis are compared with images from a healthy control group who have been matched for demographic variables. The success of image statistics for brain imaging has encouraged us to develop a method for obtaining volumetrically normalized kidney to perform image statistics so that we can locally visualize the statistical significant difference comparing voxel by voxel between certain groups in terms kidney blood flow kinetic parameters. For the development of this evolutionary process, we first volumetrically normalized all subjects, which include healthy control (HC) and chronic renal failure (CRF) patients, 15O water PET image with respect to one HC subject's MRI image using affine transformation. Then 15O kinetic parametric images of normalized kidneys were obtained through the basis function method. Finally, the statistical map of these pa...
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Simulations and numerical analysis of physical problems are important steps toward understanding underlying mechanisms of the processes. Important examples would be medical physics and medical imaging. Compartmental modeling has been... more
Simulations and numerical analysis of physical problems are important steps toward understanding underlying mechanisms of the processes. Important examples would be medical physics and medical imaging. Compartmental modeling has been found useful for estimating the transport and temporal variations of drugs/contaminants (commonly used in medical physics and medical imaging) in different organs, given that different organs would be modeled as compartments. Recycling among these modeled compartments (i.e., organs) was allowed through defining sets of constant transfer rates. In order to mathematically define these systems, one needs to use sets of differential equations (depending on the number of compartments) which would in fact be time-consuming and prone to mathematical error. Considering these issues, there is a need for a versatile computer program that is accurate, robust, and user-friendly to perform the required computations automatically. In the present work, we developed an...
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Functional near-infrared spectroscopy (fNIRS) is an optical imaging tool to study brain activities. Moreover, many researchers combined fNIRS with other modalities to gain a better understanding of the brain. This paper provides an... more
Functional near-infrared spectroscopy (fNIRS) is an optical imaging tool to study brain activities. Moreover, many researchers combined fNIRS with other modalities to gain a better understanding of the brain. This paper provides an overview of the combination of fNIRS with other imaging modalities in the detection and measurement of the cerebral hemodynamic. Cerebral haemodynamic such as the cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral blood oxygenation (CBO) are the important parameters in many neuroimaging studies. Cerebral hemodynamic had been studied by various medical imaging modalities. Initially, Xenon enhanced Computed Tomography (Xenon CT), Computed Tomography (CT) perfusion; Single Photon Emission Computed Tomography (SPECT), Positron Emission Tomography (PET) are used to measure the cerebral hemodynamic. Recently, fNIRS is used to optically observe the changes in cerebral haemodynamic during brain activities and the combination of fNIRS with other ...
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We aimed to determine whether high-resolution specimen-positron emission mammography (PEM) using fluorodeoxyglucose (F-FDG) can reveal extension of breast cancer in breast-conserving surgery (BCS), and assess the safety of radiation... more
We aimed to determine whether high-resolution specimen-positron emission mammography (PEM) using fluorodeoxyglucose (F-FDG) can reveal extension of breast cancer in breast-conserving surgery (BCS), and assess the safety of radiation exposure to medical staff. Sixteen patients underwent positron emission tomography, and then BCS with intraoperative frozen section analysis on the same day. Resected specimens with remainingF-FDG accumulation were scanned by high-resolution PEM. At least 1 day after surgery, tumour extension was evaluated by three independent experienced readers and by binarized images from the specimen-PEM data. Intraoperative exposure of medical staff toF-FDG was measured. Specimen-PEM evaluations of binarized images and the three investigators detected all (100 %, 12/12) invasive lesions and 94.4 % (17/18) of in situ lesions using both methods. The positive predictive value of the accumulated lesions was 74.4 % (29/39) for the binarized images and 82.9 % (29/35) for ...
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Research Interests: Positron Emission Tomography, Medicine, PET, PET imaging, Animals, and 15 moreHeart, Clinical Sciences, Metabolic rate, Oxygen, Myocardium, Inhalation, Swine, Reproducibility of Results, Radiopharmaceuticals, Sensitivity and Specificity, Reference Values, Oxygen Extraction Fraction, Oxygen Consumption, Tissue distribution, and Compartmental Model
As the clinical use of positron emission tomography technology grows, so does the demand for noninvasive measurement of cerebral blood flow (CBF). This chapter presents the development of a compact radiation monitor composed of dual... more
As the clinical use of positron emission tomography technology grows, so does the demand for noninvasive measurement of cerebral blood flow (CBF). This chapter presents the development of a compact radiation monitor composed of dual β-detectors suitable for the detection of radiation from superficial tissue. One detector is placed over the wrist above the radial artery to monitor arterial radioactivity, whereas another was placed on an adjacent skin area to measure the background. The monitor worked fairly well except on obese subjects, for whom an arterial count curve was not recoverable. A model has been developed to restore the arterial input function comparing the two-detector response with time that incorporated the superficial tissue flow, mainly of skin and the subcutaneous tissue. Twenty-four studies on five normal volunteers are conducted with [ 15 O]-water slow bolus injections, which are controlled by an automatic injection system. A significant correlation is obtained between the calculated CBF using restored input function by the system and the CBF using an actual arterial input curve by arterial cannulation. Further, refinement of the procedures that include the calibration of restored arterial input to well counter and accurate correction of dispersion in the restored arterial input may increase the accuracy of this noninvasive method.
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The aim of this study was to establish kinetic analysis of [5-(11)C-methoxy]donepezil ([(11)C]donepezil), which was developed for the in-vivo visualization of donepezil binding to acetylcholinesterase (AChE) using positron emission... more
The aim of this study was to establish kinetic analysis of [5-(11)C-methoxy]donepezil ([(11)C]donepezil), which was developed for the in-vivo visualization of donepezil binding to acetylcholinesterase (AChE) using positron emission tomography (PET). Donepezil is an AChE inhibitor that is widely prescribed to ameliorate the cognitive impairment of patients with dementia. Six healthy subjects took part in a dynamic study involving a 60-min PET scan after intravenous injection of [(11)C]donepezil. The total distribution volume (tDV) of [(11)C]donepezil was quantified by compartmental kinetic analysis and Logan graphical analysis. A one-tissue compartment model (1TCM) and a two-tissue compartment model (2TCM) were applied in the kinetic analysis. Goodness of fit was assessed with chi(2) criterion and Akaike&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s Information Criterion (AIC). Compared with a 1TCM, goodness of fit was significantly improved by a 2TCM. The tDVs provided by Logan graphical analysis were slightly lower than those provided by a 2TCM. The rank order of the mean tDVs in 10 regions was in line with the AChE activity reported in a previous post-mortem study. Logan graphical analysis generated voxel-wise images of tDV, revealing the overall distribution pattern of AChE in individual brains. Significant correlation was observed between tDVs calculated with and without metabolite correction for plasma time-activity curves, indicating that metabolite correction could be omitted. In conclusion, this method enables quantitative analysis of AChE and direct investigation of the pharmacokinetics of donepezil in the human brain.
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ABSTRACT Patlak graphical analyses are frequently used for the quantitative study of receptor distribution in the human brain, when the specific binding of the tracer is apparently irreversible over the time course of the study. This... more
ABSTRACT Patlak graphical analyses are frequently used for the quantitative study of receptor distribution in the human brain, when the specific binding of the tracer is apparently irreversible over the time course of the study. This chapter provides an alternative approach by spectral analysis, which allows the unit impulse response function, and hence an estimate of the irreversible disposal rate constant, to be derived. The latter technique can also be used to obtain estimates of the total volume of distribution when the binding is reversible. These two techniques have been compared and applied to the quantitative estimation of muscarinic cholinergic receptor distribution in human brain with [11C]benztropine positron emission tomography. After transmission scanning, [11C]benztropine is injected into three healthy male volunteers and serial tomographic scans are performed using a Siemens-CTI 931 PET scanner. Arterial blood samples are drawn rapidly, and plasma is separated and counted. Selected plasma samples are also analyzed for the percentage of unchanged tracer. [11C]benztropine binding is analyzed at the pixel level by both the Patlak method and spectral analysis to give quantitative parametric images of [11C]benztropine uptake. Estimates of the irreversible disposal rate constant are obtained from the terminal slope of the equivalent Patlak plot and from the value of the unit impulse response function at a late time (60-minute). Very close correlation is found at the pixel level between the two estimates. Overall, estimates obtained by spectral analysis were about 90% of those obtained by the Patlak analysis, reflecting some reversibility in the binding measured over the scan period.
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Research Interests: Endocrinology, Pharmacokinetics, Positron Emission Tomography, Medicine, Multidisciplinary, and 15 moreBiological Sciences, Internal Medicine, Animals, DNP, Male, Acetylcholinesterase, Cholinesterase inhibitors, PLoS one, Rats, Time Factors, Piperidines, Adrenal glands, Indans, Tissue distribution, and Aché
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This study evaluated the feasibility of imaging rat brains using a human whole-body 3-T magnetic resonance imaging (MRI) scanner with specially developed transmit-and-receive radiofrequency coils. The T(1)- and T(2)-weighted images... more
This study evaluated the feasibility of imaging rat brains using a human whole-body 3-T magnetic resonance imaging (MRI) scanner with specially developed transmit-and-receive radiofrequency coils. The T(1)- and T(2)-weighted images obtained showed reasonable contrast. Acquired contrast-free time-of-flight magnetic resonance angiography images clearly showed the cortical middle cerebral artery (MCA) branches, and interhemispheric differences could be observed. Dynamic susceptibility contrast MRI at 1.17 mm(3) voxel resolution, performed three times following administration of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA, 0.1 mmol/kg), demonstrated that the arterial input function (AIF) can be obtained from the MCA region, yielding cerebral blood flow (CBF), cerebral blood volume, and mean transit time (MTT) maps. The hypothalamus (HT) to parietal cortex (Pt) CBF ratio was 45.11 +/- 2.85%, and the MTT was 1.29 +/- 0.40 s in the Pt region and 2.32 +/- 0.17 s in the HT region. A single dose of Gd-DTPA enabled the assessment of AIF within MCA territory and of quantitative CBF in rats.
Research Interests: Magnetic Resonance Imaging, Nuclear medicine, Medicine, Brain, Humans, and 15 moreAnimals, Feasibility Studies, Male, Parietal Cortex, Rat Brain, Gadolinium, Radiofrequency, Cerebral Blood Flow, Contrast Media, Middle Cerebral Artery, Magnetic resonance angiography, Magnetic resonance image, Arteries, Cerebral Blood Volume, and dynamic susceptibility contrast
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Research Interests: Mathematics, Architecture, Positron Emission Tomography, Medicine, Humans, and 10 moreComputer Simulation, Clinical Sciences, Middle Aged, Cerebral, Single Photon Emission Computed Tomography, Adult, Sensitivity and Specificity, Cerebral Blood Flow, Neurosciences, and Cardiovascular medicine and haematology
Proton irradiations are highly sensitive to spatial variations, mainly due to their high linear energy transfer (LET) and densely ionizing nature. In realistic clinical applications, the targets of ionizing radiation are inhomogeneous in... more
Proton irradiations are highly sensitive to spatial variations, mainly due to their high linear energy transfer (LET) and densely ionizing nature. In realistic clinical applications, the targets of ionizing radiation are inhomogeneous in terms of geometry and chemical composition (i.e., organs in the human body). One of the main methods for proton range monitoring is to utilize the production of proton induced positron emitting radionuclides; these could be measured precisely with positron emission tomography (PET) systems. One main positron emitting radionuclide that could be used for proton range monitoring and verification was found to be 13N that produces a peak close to the Bragg peak. In the present work, we have employed the Monte Carlo method and Spectral Analysis (SA) technique to investigate the feasibility of utilizing the 13N peak for proton range monitoring and verification in inhomogeneous targets. Two different phantom types, namely, (1) ordinary slab and (2) MIRD ant...
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Radioprotective effects of vitamin C and vitamin E as a water-soluble and a lipid-soluble agent, respectively, were investigated at the molecular level during the imposition of gamma radiation-induced structural changes to bovine serum... more
Radioprotective effects of vitamin C and vitamin E as a water-soluble and a lipid-soluble agent, respectively, were investigated at the molecular level during the imposition of gamma radiation-induced structural changes to bovine serum albumin (BSA) at the therapeutic dose of 3 Gy. Secondary and tertiary structural changes of control and irradiated BSA samples were investigated using circular dichroism and fluorescence spectroscopy. The preirradiation tests showed nonspecific and reversible binding of vitamins C and E to BSA. Secondary and tertiary structures of irradiated BSA considerably changed in the absence of the vitamins. Upon irradiation, α-helices of BSA transitioned to beta motifs and random coils, and the fluorescence emission intensity decreased relative to nonirradiated BSA. In the presence of the vitamins C or E, however, the irradiated BSA was protected from these structural changes caused by reactive oxygen species (ROS). The two vitamins exhibited different patterns...
Research Interests: Medicine and Antioxidants
This article presents a theoretical investigation of the differential, integrated, elastic, inelastic, total, momentum-transfer, and viscosity cross-sections, along with the total ionization cross-section, for elastically scattered... more
This article presents a theoretical investigation of the differential, integrated, elastic, inelastic, total, momentum-transfer, and viscosity cross-sections, along with the total ionization cross-section, for elastically scattered electrons and positrons from a carbon dioxide (CO2) molecule in the incident energy range of 1 eV ≤Ei≤ 1 MeV. In addition, for the first time, we report the spin polarization of e±−CO2 scattering systems. The independent atom model (IAM) with screening correction (IAMS) using a complex optical potential was employed to solve the Dirac relativistic equation in partial-wave analysis. The comparison of our results with the available experimental data and other theoretical predictions shows a reasonable agreement in the intermediate- and high-energy regions.
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The Monte Carlo method is employed in this study to simulate the proton irradiation of a water-gel phantom. Positron-emitting radionuclides such as 11C, 15O, and 13N are scored using the Particle and Heavy Ion Transport Code System Monte... more
The Monte Carlo method is employed in this study to simulate the proton irradiation of a water-gel phantom. Positron-emitting radionuclides such as 11C, 15O, and 13N are scored using the Particle and Heavy Ion Transport Code System Monte Carlo code package. Previously, it was reported that as a result of 16O(p,2p2n)13N nuclear reaction, whose threshold energy is relatively low (5.660 MeV), a 13N peak is formed near the actual Bragg peak. Considering the generated 13N peak, we obtain offset distance values between the 13N peak and the actual Bragg peak for various incident proton energies ranging from 45 to 250 MeV, with an energy interval of 5 MeV. The offset distances fluctuate between 1.0 and 2.0 mm. For example, the offset distances between the 13N peak and the Bragg peak are 2.0, 2.0, and 1.0 mm for incident proton energies of 80, 160, and 240 MeV, respectively. These slight fluctuations for different incident proton energies are due to the relatively stable energy-dependent cro...
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Data security has become indispensable, with a view to keep sensitive information confidential. One important method is through image encryption, upon which features in an image would no longer be visible. The original image with its... more
Data security has become indispensable, with a view to keep sensitive information confidential. One important method is through image encryption, upon which features in an image would no longer be visible. The original image with its features could only be restored upon decryption using a set of keys. There are prestigious works in the literature regarding image encryption. However, there is a lack of easy-to-use, GUI-based, user-customizable computer programs for image encryption. In the present work, we developed a GUI-based image encryption and decryption program with server file transfer support, namely, SecureVision. A custom-made random number generator using the equation of an ellipse was developed to randomly shuffle the pixel positions. SecureVision was found to be robust, user-friendly and fast in both encryption and decryption. The program was highly sensitive to the supplied keys, which prevented brute-force attacks. SecureVision provided full user control, where users c...
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1 Department of Energy Engineering and Physics, Faculty of Physics, Amirkabir University of Technology, Tehran, Iran 2 Persian Gulf Research Institute, Persian Gulf University Bushehr, Iran 3 Cyclotron and Radioisotope Center (CYRIC),... more
1 Department of Energy Engineering and Physics, Faculty of Physics, Amirkabir University of Technology, Tehran, Iran 2 Persian Gulf Research Institute, Persian Gulf University Bushehr, Iran 3 Cyclotron and Radioisotope Center (CYRIC), Tohoku University, Sendai, Miyagi, Japan 4 Institute of Biochemistry & Biophysics, University of Tehran, Tehran, Iran 5 Nanobiotechnology Research Center, Baqiyatallah University of Medical Science, Tehran, Iran
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Calculations are presented for differential, integrated elastic, momentum transfer, viscosity, inelastic, total cross sections and spin polarization parameters S, T and U for electrons and positrons scattering from atoms and ions of radon... more
Calculations are presented for differential, integrated elastic, momentum transfer, viscosity, inelastic, total cross sections and spin polarization parameters S, T and U for electrons and positrons scattering from atoms and ions of radon isonuclear series in the energy range from 1 eV–1 MeV. In addition, we analyze systematically the details of the critical minima in the elastic differential cross sections along with the positions of the corresponding maximum polarization points in the Sherman function for the aforesaid scattering systems. Coulomb glory is investigated across the ionic series. A short range complex optical potential, comprising static, polarization and exchange (for electron projectile) potentials, is used to describe the scattering from neutral atom. This potential is supplemented by the Coulomb potential for the same purpose for a charged atom. The Dirac partial wave analysis, employing the aforesaid potential, is carried out to calculate the aforesaid scattering...
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Molecular imaging serves as an important tool for researchers and clinicians to visualize and investigate complex biochemical phenomena using specialized instruments; these instruments are either used individually or in combination with... more
Molecular imaging serves as an important tool for researchers and clinicians to visualize and investigate complex biochemical phenomena using specialized instruments; these instruments are either used individually or in combination with targeted imaging agents to obtain images related to specific diseases with high sensitivity, specificity, and signal-to-noise ratios. However, molecular imaging, which is a multidisciplinary research field, faces several challenges, including the integration of imaging informatics with bioinformatics and medical informatics, requirement of reliable and robust image analysis algorithms, effective quality control of imaging facilities, and those related to individualized disease mapping, data sharing, software architecture, and knowledge management. As a cost-effective and open-source approach to address these challenges related to molecular imaging, we develop a flexible, transparent, and secure infrastructure, named MIRA, which stands for Molecular I...