valiallah saba

In angiography and especially in angioplasty, large amounts of X-rays are emitted to the patient’s body, which causes the patient to be exposed to a lot of radiation. Saba Shield is a type of highpass shield that was introduced recently. Moreover, its effectiveness in reducing the dose of patients during CT scan imaging has been investigated and confirmed. It seems that the use of Saba shield with optimal thickness can significantly reduce the dose received by patients in angiography and angioplasty. The aim of this study is to investigate the effectiveness of Saba Shield with Zn-Bi combination on reducing the dose received by patients and its effect on the quality of images in angiography and angioplasty.

Methods and Materials:

 One shield with dimensions of 60 x 40 cm and thickness of 0.04 mm equivalent to lead was prepared in order to investigate the efficiency of Saba shield with Zn-Bi combination in angiography and angioplasty. Angiography machine was used for radiation and CTDI phantom was used to simulate the patient’s body. Dosimetry using TLDs was performed on the CTDI phantom without shield and with shield.Then, the values of dose reduction and image quality were examined. In order to check the quality of the image, according to the radiology experts, it was used in a double-blind manner.

The findings of the present study showed that the use of Saba Shield with Zn-Bi combination in angiography and angioplasty has reduced the dose between 30 and 37% of the dose received by patients with moderate and acceptable image quality.

Saba shield with Zn-Bi composition and thickness of 0.04 mm equivalent to lead can significantly reduce the dose received by the patients and it does not have a degrading effect on the quality of the images.

Military missions involve stressful and life-threatening situations; however, soldiers should have a healthy cognition on the battlefield despite their high-stress levels. This is an ability that should be gained during prior military training. Successful and influential training is suggested to be associated with structural and functional improvements of the brain.

This study investigated the pattern of brain activation while observing videos relevant to life-threatening situations, in addition to brain structure. Accordingly, the obtained data were compared between 20 military members and 26 healthy controls. The study participants were all male, aged between 19 to 24 years, right-handed, studying BSc, and from the same socioeconomic status.

The obtained data presented a larger volume in a total number of 1103 voxels of the brain (in 5 brain areas) in the military group. Furthermore, the military group suggested higher brain activation in the visual processing areas of the brain when observing real combat videos; however, this increment was mostly in the areas associated with motor processing and executive functions in the controls.

This study indicated that military training is associated with positive structural changes in the brain. Besides, it provided a different brain activation in response to stressful situations. These findings highlighted the importance of qualified military training.

Ionizing radiation induces deleterious effects in the biological systems by producing free radicals. Grape Seed Extract (GSE) as a free radical scavenger could protect the body against the damages. In this study, 12 healthy male volunteers were divided into Groups 1, 2, 3 and 4 and received 100, 300, 600 and 1000 mg GSE, respectively. Peripheral blood samples were collected from each volunteer 15 min before, and 1, 2, and 5 hr after GSE oral administration. Blood samples were then irradiated with 150 cGy of 100 kvp X-ray (Irradiated control group, was treated with only 1.5 Gy of X-rays). Cytogenic damages were detected by micronucleus assay. Results showed that irradiation significantly increased the incidence of micronuclei (p Consumption of GSE before undergoing radiation protects human lymphocytes against X-rays by reducing radiation-induced genotoxicity.

Dynamic alterations of the brain are of high significance when it comes to analyze the human feelings. In this study, the hidden patterns corresponding for the emotional states have been investigated by adopting a certain Poincare’ map function inspired by the theory of chaos. The present study aimed to explore the significance relationship between the proposed methodology and the level of the emotional states. Methods and Materials: One of the well-known emotion dataset namely ‘DEAP’ was used to evaluate the performance of our methodology. DEAP is a multimodal dataset in which forty music videos lasting one minute were shown to 32 participants. Moreover, a set of 40 channels of biological signals including EEG and peripheral signals were recorded. Moreover, participants rated to each video in terms of ‘valence’, ‘arousal’, ‘dominance’, and ‘liking’. In this study we have investigated the dynamic variations of EEG signals in order to discriminate the levels of the emotional states. For describing the effect of the Poincare’ approach on the subjective ratings, we have adopted the correlation statistics by computing the Spearman correlated coefficients. The results indicate that the Poincare approach could properly discriminate the levels of valence (p<0.05), arousal (p<0.01), dominance (p<0.05), and liking (p<0.05). In other words, the statistical analysis showed the significant relationship between the levels of emotions and the Poincare’ method. Discussion and The result interpretations demonstrate and verify the success of the nonlinear and chaotic approaches in the analysis of human brain signals. Therefore, it could be a reliable methodology for studying the brain functions.

By increasing life expectancy in the world, especially in developed countries, Alzheimer’s disease has become one of the most important and costly diseases. It is estimated that the prevalence of dementia will double every 5 years for people over 60 years. Unfortunately, this disease and other types of dementias impose a heavy burden on the economies of societies. In this study an automated method is presented and evaluated for Alzheimer disease detection in order to assist physician diagnosis. Methods and Materials: Magnetic resonance images of 236 patients were used. First, the gray and white matter regions and cerebrospinal fluid were extracted by image processing methods and their area were calculated and considered as feature vector for classification. Then, the support vector machine and neural networks were used to classify the Alzheimer patients from healthy ones. The gray matter region areas were significantly lower in Alzheimer group than healthy one. Using the regions area as feature vector and by means of support vector machine and neural networks as classifiers, a detection accuracy of 85% was achieved. Discussion and Alzheimer disease reduces the area of gray matter in brain which this changes are irreversible. Intellectual methods can detect this changes and diagnose Alzheimer disease. This methods could be used to assist physician for detection of disease.

Epidemiological studies show that computed tomography (CT) is one of the main sources of ionizing radiations. Shielding of radiosensitive organs is one of the dose reduction methods. This study aimed to assess the eye lens dose reduction and image quality resulting from the use of radio-protective bismuth shield in brain CT imaging. Bismuth shields were constructed with two different thicknesses (0.02 and 0.06 cm) and two different geometries including: direct contact with eye (contact setup) and 4 cm above the eye (distant setup). The lens dose was determined using thermo luminescent dosimeter (TLD)-207A chips inside an anthropomorphic head phantom during the CT examinations. Noise, SNR (signal to noise ratio), and CNR (contrast to noise ratio) were calculated to evaluate the image quality. The lens dose reduction was higher using the shield with 0.06 cm thickness and in ‘contact setup’. On the other hand, the bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ had lower dose reduction and better image quality. Bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ could decrease the lens dose to the acceptable levels, while providing a better image quality in comparison with the contact shield setup and with 0.06 cm thickness. Using the bismuth shield is a simple and low cost method for protecting the eye lens in brain CT scans with conventional scanners especially in low income or developing countries.

Cortical Spreading Depression (CSD) is a propagating wave of neural and glial cell depolarization with important role in several clinical disorders. Repetitive Transcranial Magnetic Stimulation (rTMS) is a potential tool with preventive treatment effects in psychiatric and neuronal disorders. In this paper, we study the effects of rTMS on CSD by using behavioral and histological approaches in hippocampus and cortical regions.
Twenty-four rats were divided into four groups. A group of control rats were kept in their home cage during the experiment. The CSD group received four CSD inductions during 4 weeks with 1 week intervals. The CSD-rTMS group were treated with rTMS stimulation (figure-eight coils, 20 Hz, 10 min/d) for 4 weeks. The fourth group, i.e. rTMS group received rTMS stimulation similar to the CSD-rTMS group without CSD induction.
Long-term rTMS application in treated groups significantly reduced production of dark neurons, increased the mean volume of normal neurons, and decreased the number of apoptotic neurons in cortical regions compared to the control group. The protective effects of long-term treatment by rTMS in the hippocampal regions were also studied. It was effective in some regions; however, rTMS effects on hippocampal regions were lower than cortical ones.
Based on the study results, rTMS has significant preventive and protective effects in CSD-induced damages in cortical and hippocampal regions of the rat’s brain.

Exposure rate constant (G) relates activity of a point source to exposure rate at certain distance. It’s an important parameter in radiation protection, medical uses and radiological assessments. In this study exposure rate constant for three radionuclides include 60Co, 22Na and 111In were calculated with FLUKA Monte Carlo method. Each sources simulated and exposure rate at different distances of 20, 30, 40, 60, 80, 100, 120, 150, 200 and 300cm from the sources were measured. For dose measurements we simulate a farmer ionization chamber with active volume of 0.6cm3, inner electrode of aluminium with diameter of1mm and wall of pure graphite with thickness of 0.75mm. Calculated exposure rate constants for 60Co, 22Na and 111In at 20 to 300cm from the source ranged from 33.45 to 0.16 mR/(mCi.h), 29.12 to 0.10 mR/(mCi.h) and 8.73 to 0.03 mR/(mCi.h) respectively which show a decreasing trend. Comparison of our results with other studies show that there are good agreement for 60Co and 22Na, our values for exposure rate constant for 111In was higher than previous reports.

Eye lens is a very sensitive organ to the x-ray radiation and cataract could be formed as a result of eye exposure. Computed tomography (CT) is one of the main exposure sources in clinical situations and brain imaging delivers high amount of exposure to the eye lens. To reduce eye lens dose, efficient dose reduction methods have to be developed and implemented. In this paper, the efficiency of two methods including gantry tilting and kVp reduction, have been studied for eye lens dose reduction.
Methods and Materials: A 64-slice CT scanner was modeled to evaluate the eye lens dose in different scanning arrangements using MCNPx. To study the effect of kVp reduction and gantry tilting on the Lens dose magnitudes, three tube voltages including 100, 120 and 140 kVp and three gantry tilts including 0, 15 and 30 degrees were simulated and studied.
The results showed that the lens dose considerably decreased by tube voltage decreasing and gantry tilt increasing.
Discussion and From the results, it could be concluded that low tube voltage and gantry tilting are effective and simple methods for lens dose reduction in CT scan.

In diagnostic and therapeutic procedures, dosimetric studies are performed on the dosimetric systems in order to comply the radiation safety standards. Monte Carlo methods are used due to the high complexity and cost of patient-specific phantom construction. The high complexity of the digitized phantoms greatly increases the time and computational task of the Monte Carlo calculation. In many studies, all of the defined components and high precision of the voxelized phantom are not necessary and the study objectives could be achieved by a simple digital phantom modeling. In this study, an anatomic-based human head phantom was modeled considering the importance of the digitized phantoms for Monte Carlo dosimetry measurements.
Methods and Materials: In this study, the anthropomorphic head phantom was simulated using MCNPx (version 2.4.0). The proposed head phantom consist of the skull, brain, eyes, eye lens, facial bones, neck and skin that are modeled based on the atomic compositions and density magnitudes reported by ICRU report No. 44 and the national institute of standards and technology (NIST) reports.
The visual and structural characteristics of the modeled head phantom in different cross-sectional views were evaluated by two scientific experts. For modeled phantom, integrity and compliance of the structural features with the actual human head were confirmed by the experts.Simulated phantom is flexible and upgradeable. According to study objectives, other tissues including tumors, the specific tissue of interest, and etc. could be added to the model.
Discussion and Pre-clinical dosimetric studies including the determination of dose to organ at risks in the diagnostic and therapeutic situations as well as the effect of shielding methods and imaging geometries in the image quality could be evaluated using the modeled phantom.

SURGEOSIGHT is a dedicated intra-operative hand-held gamma camera designed and manufactured by our team to be used for lymphoscintigraphy. Although conventional gamma cameras are widely used, they lack the capability of the sentinel lymph node (SLN) imaging in the operation room. Like conventional gamma cameras it is necessary to calibrate SURGEOSIGHT for linearity distortion, energy and flood correction. Our main objective in this study is to develop and implement three techniques for linearity, energy and uniformity corrections.
The camera is made up of a pixelated cesium iodide (sodium-activated) (CsI(Na)) scintillation crystal with 1 × 1 mm2 element size along with a Hamamatsu H8500 flat-panel multi-anode (64 channels) photomultiplier tube. All triple corrections required lookup tables (LUTs). To generate all three LUTs, one uncalibrated acquisition is necessary. Linearity distortion correction was based on localization of physical pixels of crystal and thin plate spline interpolation to estimate the amount of distortion. Energy correction LUT was simply a photo-peak map of incoming events which was estimated using self-organizing map technique.
The results showed improvements qualitatively and quantitatively. The extrinsic energy resolution was enhanced from 50% to about 20.6%. Integral uniformity and the differential uniformity, after uniformity correction, in useful field-of-view (UFOV) was measured 9.5% and 4.5%, respectively.
Results substantiated that the correction techniques guarantee uniform and accurate output of the SURGEOSIGHT which is desirable for intra-operative localization of the sentinel lymph nodes in breast cancer and also for imaging of other superficial tumors.

Lung cancer is the most common and most deadly cancer in most of countries of the world. One of the most significant problems with this cancer is the lack of accurate and specific statistics about the prevalence and mortality rate in Iran. Results of cancer registry program in 2008 in Iran indicated a low incidence rate of lung cancer. However, these statistics were wrong and far from the reality. Several other studies have been done in Iran demonstrating high incidence rates of lung cancer. On the recent recommendation of international organizations such as, the American Cancer Society (ACS), the American College of Radiology ACR, and the International Association for the Study of Lung Cancer IASLC in 2013, the most effective method for the prevention of mortality due to lung cancer is the annual screening of high risk people with low dose computed tomography (LDCT). The cost effectiveness of this program should be evaluated before the implementation of it in the country.
Methods and Materials: The most important benefit of implementing screening is the increase of lung cancers early detection rate. This is the main basis for calculating the cost effectiveness in different countries. The cost effectiveness of the project has been estimated by using the data in the country and basing on the results of an important project carried out in America and Netherlands (the international NLST project in America and the international NELSON project in Netherland). In addition, the early detection rate was estimated and compared with others.
Our analysis indicates that the implementation of screening will increase the early detection rate about 500% in the country. However, the early detection rate has been increased about 200% in NLST project. Thus, it is estimated that the implementation of this program will have more efficiency in Iran than American and European countries.
Discussion and Lung cancer is one of the most common cancers in Iran; moreover, screening this cancer can rescue the thousands lives of our compatriots annually. Unfortunately, there are no plans to implement and enforce the screening in the country. It seems a incorrect statistics announced by the national cancer registry center in 2008 that showed the low incidence rate of this cancer is the basis for relevant authorities’ decision making. High cigarette consumption, air pollution in metropolis, and the mean age of the elderly are all the alarm for raising this cancer in the country. Screening the lung cancer with low dose CT imaging is considered as the most effective way to control and prevent deaths from this cancer in the country, so it should be paid serious attention by the relevant authorities.

To assess three main emotions (happy, sad and calm) by various classifiers, using appropriate feature extraction and feature selection.
In this study a combination of Power Spectral Density and a series of statistical features are proposed as statistical-frequency features. Next, a feature selection method from pattern recognition (PR) Tools is presented to extract major features and apply to classifiers.
The experimental results on various classifiers demonstrated the priority of proposed emotion assessment system to the previous ones where Back-Propagation Neural Network was the most accurate classifier to complete the proposed system and Linear Discriminant Analysis was the best choice regarding to the accuracy and runtime of the system.
In this paper we proposed a prominent method that led to a highly accurate system with three emotion states. In this regard, unequal numbers of experiments on different emotion states were employed. This idea indicated that in order to avoid domination of one emotion state rather than other states in self-induced emotion signals unequal number of different states should be applied.

The art of voice mimicking by computers, has with the computer have been one of the most challenging topics of speech processing in recent years. The system of voice conversion has two sides. In one side, the speaker is the source that his or her voice has been changed for mimicking the target speaker’s voice (which is on the other side). Two methods of parallel and non-parallel training are used for voice conversion. In parallel method, both source and target speakers express the same sentences while different sentences are expressed in non-parallel method. Most of the voice conversion researchers prefer to use parallel training; however, there is not always the possibility of collecting parallel data. Therefore, there is a need for using non-parallel methods.
Methods and Materials: Source and target speakers’ voice was recorded and then analyzed. Voice features of both speakers were extracted by signal processing. Then the action of alignment has been done and the function of voice conversion was obtained. Source voice has been analyzed and the action of extracting feature has been carried out in order to convert source voice to the target. Voice conversion function from the previous section was applied on the extracted features. Then, the reverse action of features was done and finally, the voice synthesis took place. Moreover, the synthesized voice is the voice of target person.
The results of both numerical and objective experiments demonstrated that our proposed method is better than parallel training methods. It was observed that this superiority holds for different sizes of training material from 5 to 40 training sentences, both in terms of quality and similarity to the target speaker.
Discussion and It seems that our proposed method is a serious competitor of parallel training method for from alignment.

Brain Computer Interface (BCI) systems based on Movement Imagination (MI) are widely used in recent decades. Separate feature extraction methods are employed in the MI data sets and classified in Virtual Reality (VR) environments for real-time applications. This study applied wide variety of features on the recorded data using Linear Discriminant Analysis (LDA) classifier to select the best feature sets in the offline mode. The data set was recorded in 3-class tasks of the left hand, the right hand, and the foot motor imagery. The experimental results showed that Auto-Regressive (AR), Mean Absolute Value (MAV), and Band Power (BP) features have higher accuracy values,75% more than those for the other features. These features were selected for the designed real-time navigation. The corresponding results revealed the subject-specific nature of the MI-based BCI system; however, the Power Spectral Density (PSD) based α-BP feature had the highest averaged accuracy.

lung cancer is the most deadly and the most expensive cancer all around the world. Limited studies have been conducted in the survey of incidence rate for lung cancer in IRAN. National report of cancer registry in IRAN (report 2008) indicates that mean value of ASR of lung cancer is 5.23 for men and women (7.09 for men and 3.38 for women). These values are so different from the values of Globocan 2008 report which indicates that mean value of lung cancer ASR for men and women is 23.6 (33.8 for men and 13.5 for women). The authors of report 2008 in IRAN have declared that the calculated ASR for lung cancers is abnormal and unexpected. Another study has been done in Golestan province and its results have been published in IARC. In this study, the mean ASR of lung cancer has been reported equal to 11.55 (17.5 for men and 5.6 for women). The actual value of lung cancer ASR is so controversial in IRAN in this study we estimated the value of ASR considering the main risk factors and using a linear mathematical model. a comprehensive study on lung cancer’s statistics was conducted in three countries of America, England, and Turkey in the last 15 years. Statistics were extracted on the number of smokers and the percentage of the elderly (the most important risk factors for lung cancer) and ASR of lung cancer of these countries. Then by interpolating data of the three countries, a model was extracted for estimating the lung cancer of IRAN. The output of the model (analysis mode1) shows that the rate of lung cancer ASR is equal to 9.7 and 27 in 2014 and 2030 respectively. In another estimate (analysis mode2) given that Turkey is a country neighboring Iran, America and Britain, the two countries have been removed from the calculation and the only Turkish statistics were used for interpolation and approximation of lung cancer ASR. In this mode, ASR of the country was estimate 12 and 33.9 in 2014 and 2030 respectively. Based on the analysis mode1, the number of new lung cancer cases is estimated 8000 and 28890 individuals in 2014 and 2030 respectively. Based on the analysis mode2, the number of new lung cancer cases is estimated 9600 and 36380 individuals in 2014 and 2030 respectively.Discussion and The above estimations indicate that the lung cancer will be the most deadly and the most common cancer in the country in close future. Whereas, that smoking does not increase in the coming years, in the case of increasing in smoking, the situation will become more critical and complex. Our study indicates that we will have a serious challenge in our country in close future about lung cancer. To control and manage this problem, lung cancer screening with LDCT is an emergency program that should be planned, tested and implemented.

Different views of an individuals’ image may be required for proper face recognition. Recently, discrete cosines transform (DCT) based method has been used to synthesize virtual views of an image using only one frontal image. In this work the performance of two different algorithms was examined to produce virtual views of one frontal image. Two new methods, based on neural networks (NN) and principle component analysis (PCA) were used to make virtual views of an image. The results were compared with those of the DCT-based method. Two distance metrics, i.e. mean square error (MSE) and structural similarity index measure (SSIM), were used to measure and compare image qualities. About 400 data were used to evaluate the performance of the new proposed methods. The neural networks fail to improve the quality of virtually produced images. However, principle component analysis improved the quality of the synthesized images about 3%. Principle component analysis is better than both DCT-based and neural network methods for synthesizing virtual views of an image.

Epilepsy has been known as a chronic brain disorder, influences large number of population around the world. Seizures should be treated as soon as possible to avoid the development of chronic epilepsy. Furthermore, there are some complications following surgical resection of epileptic focus and drug treatment. Transcranial magnetic stimulation has been suggested to generate current flow in the brain and could be an alternative to drug treatment or surgery. We study the protective effects of repetitive transcranial magnetic stimulation (rTMS) on seizure attacks and cellular damage in the amygdala in rats.
In the present study four groups of rats including intact, pentylenetetrazole, rTMSꗩ垧竗궭골 and rTMS were used to investigate rTMS effects on cellular activity and seizure attacks in a model of epilepsy. The rTMS was applied for a month and then seizures was induced by intraperitoneally injection of pentylenetetrazole and seizure scores were determined. Finally, rats were killed and neuronal injury was evaluated in the amygdala.
Seizure scores as well as histological assessment revealed a significant reduction on seizure attacks and the mean number of necrotic cells in the amygdala following rTMS application.
This study advocated a protective effect of rTMS on cellular structure in epilepsy. However, safety of rTMS in clinical practice need further investigations.

The objective of this study is development of driver’s sleepiness using Visually Evoked Potentials (VEP). VEP computed from EEG signals from the visual cortex. We use the Steady State VEPs (SSVEPs) that are one of the most important EEG signals used in human computer interface systems. SSVEP is a response to visual stimuli presented. We present a classification method to discriminate between closed eyes and opened eyes. Fourier transforms and power spectrum density features extracted from signals and Multilayer perceptron and radial basis function neural networks used for classification. The experimental results show an accuracy of 97% for test data.