349 research outputs found
Mercury chloride-induced oxidative stress in human erythrocytes and the effect of vitamins C and E in vitro
Mercury can exist in the environment as metal, as monovalent and divalent salts and as organomercurials, one of the most important of which is mercuric chloride (HgCl2). It has been shown to induce oxidative stress in erythrocytes through the generation of free radicals and alteration of thecellular antioxidant defense system. The effect of simultaneous pretreatment with vitamins C and E on the toxicity of HgCl2 in human erythrocytes was evaluated. We examined the effect of several differentdoses of HgCl2 (1.052, 5.262, 10.524 M), or HgCl2 in combination with vitamin C (VC; 10 M) and vitamin E (VE; 30 M), on the levels of malondialdehyde (MDA) and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in human erythrocytes in vitro. Erythrocytes were incubated under various treatment conditions (HgCl2 alone, vitamins alone, or HgCl2 plus vitamin) at 37°C for 60 min and the levels of MDA and SOD, CAT and GPx activities, were determined. Treatment with HgCl2 alone increased the levels of MDA and decreased SOD, CAT and GPx activities in erythrocytes (P < 0.05). VC and VE-pretreated erythrocytes showed a significant protection aganist thecytotoxic effects induced by HgCl2 on the studied parameters. There were no statistical differences among VC+VE-treated erythrocytes, as compared to non-treated control cells. These results indicated that the presence of vitamins at concentrations that are similar to the levels found in plasma could be able to ameliorate HgCl2-induced oxidative stress by decreasing lipid peroxidation and altering antioxidant defense system in erythrocytes
Design and determination of stator geometry for axial flux permanent magnet free rod rotor synchronous motor
During designing a new axial flux permanent magnet free rod rotor synchronous motor, it is important to know before hand in which phase the largest angular velocity can occur, what is the ways to reduce the power consumption, how to achieve to increase or decrease the rotation speed by changing the core geometry. Therefore, presenting these preliminary information that are necessary for the design of a free rod rotor synchronous motor to the researchers is the aim of this work. In this respect, this study presents the design and geometrical dimensions of the stator for a new synchronous motor which is an axial flux permanent magnet free rod machine with three, four, five and six phases. This type of motors are an innovative approach especially for the applications used in industrial stirrers. Each type of stator is designed such that it has an appropriate number of phases. The rotating magnetic field over the stator is established by a PIC based microcontroller feeding the interface circuit to the stator wounds. The maximum angular speeds of bar magnet rotors with four different lengths and masses are calculated theoretically and determined experimentally. In addition, the effects of the distance between the rotor and stator, the angular speed of the rotor within the limits of the operation, and the volume of the liquid to be stirred to the power applied are investigated. Furthermore, the effects of the lengths and angular speeds of the bar magnet rotors to the distance between the rotor and stator are determined. In the light of the information obtained and taking into account the power used, the most appropriate parameters and variables such as the stator geometry changing with the phase used, the length of rotor, the distance between the rotor and stator and the angular speeds of rotor are determined. © 2011 Elsevier Ltd. All rights reserved
Assessment of procedure related anxiety and depression in oncologic patients before F-18 FDG PET-CT imaging
Background: The aim of this study was to study objectively the level of anxiety and depression in patients undergoing positron emission tomography-computed tomography (PET-CT).One hundred and forty four oncologic out-patients (76 male, 68 female) were included in this study. Methods: All patients were referred to Nuclear Medicine Department for Fluorine-18 fluorodeoxyglucose (F-18 FDG) PET-CT imaging for the assessment of their malignant or possibly malignant diseases. The Hospital Anxiety Depression Scale and the State and Trait Anxiety Inventory I and II were used to evaluate the anxiety and depression levels in these patients. Results: The mean anxiety and depression scores of The Hospital Anxiety Depression Scale prior to F-18 FDG PET-CT were 9.2 ( ± 3.8) and 6.6 ( ± 3.4), respectively. The mean state and trait anxiety scores of the State and Trait Anxiety Inventory I and II prior to F-18 FDG PET-CT were 40.4 (± 8.5) and 46.62 ± 7.8, respectively. The Hospital Anxiety Depression Scale and the State and Trait Anxiety Inventory I and II anxiety scores were found to be significantly higher in female patients, smokers and in patients with higher stage disease. Conclusion: Our results suggest that F-18 FDG PET-CT imaging may at least contribute to patient's baseline anxiety which is already generated by being an oncology patient, and thus nuclear medicine physicians should handle the patients with extra care to minimize this affect. © 2015, Umut Elboga, et al
Numerical analysis for remote identification of materials with magnetic characteristics
There is a variety of methods used for remote sensing of objects such as acoustic, ground penetration radar detection, electromagnetic induction spectroscopy, infrared imaging, thermal neutron activation, core four-pole resonance, neutron backscattering, X-ray backscattering, and magnetic anomaly. The method that has to be used can be determined by the type of material, geographical location (underground or water), etc. Recent studies have been concentrated on the improvement of the criteria such as sensing distances, accuracy, and power consumption. In this paper, anomalies created by materials with magnetic characteristics at the perpendicular component of the Earth magnetic field have been detected by using a KMZ51 anisotropic magnetoresistive sensor with high sensitivity and low power consumption, and also, the effects of physical properties of materials on magnetic anomaly have been investigated. By analyzing the graphics obtained by 2-D motion of the sensor over the material, the most appropriate mathematical curves and formulas have been determined. Based on the physical properties of the magnetic material, the variations of the variables constituting the formulas of the curves have been analyzed. The contribution of this paper is the use of the results of these analyses for the purpose of identification of an unknown magnetic material. This is a new approach for the detection and determination of materials with magnetic characteristics by sensing the variation at the perpendicular component of the Earth magnetic field. The identification process has been explained in detail in this paper. © 2011 IEEE
A new wireless asynchronous data communications module for industrial applications
All the sensors such as temperature, humidity, and pressure used in industry provide analog outputs as inputs for their control units. Wireless transmission of the data has advantages on wired transmission such as USB port, parallel port and serial port and therefore has great importance for industrial applications. In this work, a new wireless asynchronous data communications module has been developed to send the earth magnetic field data around a ferromagnetic material detected by a KMZ51 AMR sensor. The transmitter module transmits the analog data obtained from a source to a computer environment where they are stored and then presented in a graphical form. In this design, an amplitude shift keying (ASK) transceiver working at the frequency of 433.92 MHz which is a frequency inside the so called Industrial Scientific Medical band (ISM band) used for wireless communications. The analog data first fed into a 10-bit ADC controlled by a PIC microcontroller and then the digital data is sent to the transmitter. A preamble bit string is added in front of the data bits and another bit string for achieving synchronization and determination the start of the data is used. The data arriving at the receiver is taken by the microcontroller and sent to a LCD display as well as the serial port of a computer where it is written in a text file. A Visual Basic based graphics interface is designed to receive, store and present the data in the form of graphical shapes. In the paper, all the work has been explained in detail. © 2013 Published by Elsevier Ltd. All rights reserved
An Analysis by Synthesis Approach for Automatic Vertebral Shape Identification in Clinical QCT
Quantitative computed tomography (QCT) is a widely used tool for osteoporosis
diagnosis and monitoring. The assessment of cortical markers like cortical bone
mineral density (BMD) and thickness is a demanding task, mainly because of the
limited spatial resolution of QCT. We propose a direct model based method to
automatically identify the surface through the center of the cortex of human
vertebra. We develop a statistical bone model and analyze its probability
distribution after the imaging process. Using an as-rigid-as-possible
deformation we find the cortical surface that maximizes the likelihood of our
model given the input volume. Using the European Spine Phantom (ESP) and a high
resolution \mu CT scan of a cadaveric vertebra, we show that the proposed
method is able to accurately identify the real center of cortex ex-vivo. To
demonstrate the in-vivo applicability of our method we use manually obtained
surfaces for comparison.Comment: Presented on German Conference on Pattern Recognition (GCPR) 2018 in
Stuttgar
Heterotopic Ossification in the Paraplegic Patients
Heterotopic ossification is a process characterized by the formation of genuine new bone in soft tissues especially between muscle and joint capsule and frequently encountered after spinal cord and traumatic brain injury. A 35-year-old woman who had developed severe pain and decrease in range of motion in her bilateral hip after 11 months following a spinal cord injury referred to our department for bone scintigraphy is presented
Regional Distributions of Distant Metastases Detected in Differentiated Thyroid Cancers
Aim: The aim of our multicenter study is to determine retrospectively the regional distributions of distant metastases which are detected in differentiated thyroid cancers (DTC). Material and Method:Thirty-two of 960 patients with distant metastases who were given radioiodine (RAI) treatment in Gaziantep University School of Medicine and Mustafa Kemal University School of Medicine were included to study. Six of patients were male, 26 of them were female. Mean age was 52 15.4. Hystopathological diagnoses were reported as papillary thyroid cancer in 23 patients and folliculary thyroid cancer in 9 patients. The distant metastasis ratio, metastasis regions and distributions were determined. Results: It was observed only lung metastasis in 18 (56.25 b), only bone metastasis in 6 (18.75 To), combination of lung and bone metastases in 3 (9.4 %), other organ metastases accompanying to bone and lung metastases in 5 (9.4 %) (liver, soft tissue, mediastinum) and multipl organ involvoment in 2 (6.2 96) of patients. It was determined single metastasis region in 24 (75 To), 2 metastasis regions in 6 (18.75 glo) and multipl metastasis regions in 2 (6.25 WO of patients. Discussion: Distant metastases are the biggest problem in treatment and follow-up of DTCs. It is very important to diagnosis of metastases and determine the regions of involvoment in these patients
Antioxidant Status, Lipid Peroxidation and Testis-histoarchitecture Induced by Lead Nitrate and Mercury Chloride in Male Rats
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