Search results for: dose calculation

Authors: Xia Chen, Yulan Wang

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purpose: To compare the accuracy of Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, Emmetropia Verifying Optical (EVO) and Kane for intraocular lens power calculation in patients with axial length (AL) ≥ 28 mm. Methods: In this retrospective single-center study, 50 eyes of 41 patients with AL ≥ 28 mm that underwent uneventful cataract surgery were enrolled. The actual postoperative refractive results were compared to the predicted refraction calculated with different formulas (Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, EVO and Kane). The mean absolute prediction errors (MAE) 1 month postoperatively were compared. Results: The MAE of different formulas were as follows: Haigis (0.509), SRK/T (0.705), T2 (0.999), Holladay 1 (0.714), Hoffer Q (0.583), Barrett Universal II (0.552), EVO (0.463) and Kane (0.441). No significant difference was found among the different formulas (P = .122). The Kane and EVO formulas achieved the lowest level of mean prediction error (PE) and median absolute error (MedAE) (p < 0.05). Conclusion: The Kane and EVO formulas had a better success rate than others in predicting IOL power in high myopic eyes with AL longer than 28 mm in this study.

Keywords: cataract, power calculation formulas, intraocular lens, long axial length

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Authors: Ravi Kiran Pothamsetty, Radha Rani Ghosh, Baby Paul Thaliath

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Radiation therapy has undergone many advancements and evloved from 2D to 3D. Recently, with rapid pace of drug discoveries, cutting edge technology, and clinical trials has made innovative advancements in computer technology and treatment planning and upgraded to intensity modulated radiotherapy (IMRT) which delivers in homogenous dose to tumor and normal tissues. The present study was a hospital-based experience comparing two different conformal radiotherapy techniques for brain tumors. This analytical study design has been conducted at Regional Cancer Centre, India from January 2014 to January 2015. Ten patients have been selected after inclusion and exclusion criteria. All the patients were treated on Artiste Siemens Linac Accelerator. The tolerance level for maximum dose was 6.0 Gyfor lenses and 54.0 Gy for brain stem, optic chiasm and optical nerves as per RTOG criteria. Mean and standard deviation values of PTV98%, PTV 95% and PTV 2% in IMRT were 93.16±2.9, 95.01±3.4 and 103.1±1.1 respectively; for 3DCRT were 91.4±4.7, 94.17±2.6 and 102.7±0.39 respectively. PTV max dose (%) in IMRT and 3D-CRT were 104.7±0.96 and 103.9±1.0 respectively. Maximum dose to the tumor can be delivered with IMRT with acceptable toxicity limits. Variables such as expertise, location of tumor, patient condition, and TPS influence the outcome of the treatment.

Keywords: brain tumors, intensity modulated radiotherapy (IMRT), three dimensional conformal radiotherapy (3D-CRT), radiation therapy oncology group (RTOG)

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Authors: Vikas S. Minchekar

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The eyewitness is a crucial source of evidence in the criminal judicial system. However, rely on the reminiscence of an eyewitness especially intoxicated eyewitness is not always judicious. It might lead to some serious consequences. Day by day, alcohol-related crimes or the criminal incidences in bars, nightclubs, and restaurants are increasing rapidly. Tackling such cases is very complicated to any investigation officers. The people in that incidents are violated due to the alcohol consumption hence, their ability to identify the suspects or recall these phenomena is affected. The studies on the effects of alcohol consumption on motor activities such as driving and surgeries have received much attention. However, the effect of alcohol intoxication on memory has received little attention from the psychology, law, forensic and criminology scholars across the world. In the Indian context, the published articles on this issue are equal to none up to present day. This field experiment investigation aimed at to finding out the effect of alcohol consumption on identification accuracy in lineups. Forty adult, social drinkers, and twenty sober adults were randomly recruited for the study. The sober adults were assigned into 'placebo' beverage group while social drinkers were divided into two group e. g. 'low dose' of alcohol (0.2 g/kg) and 'high dose' of alcohol (0.8 g/kg). The social drinkers were divided in such a way that their level of blood-alcohol concentration (BAC) will become different. After administering the beverages for the placebo group and liquor to the social drinkers for 40 to 50 minutes of the period, the five-minute video clip of mock crime is shown to all in a group of four to five members. After the exposure of video, clip subjects were given 10 portraits and asked them to recognize whether they are involved in mock crime or not. Moreover, they were also asked to describe the incident. The subjects were given two opportunities to recognize the portraits and to describe the events; the first opportunity is given immediately after the video clip and the second was 24 hours later. The obtained data were analyzed by one-way ANOVA and Scheffe’s posthoc multiple comparison tests. The results indicated that the 'high dose' group is remarkably different from the 'placebo' and 'low dose' groups. But, the 'placebo' and 'low dose' groups are equally performed. The subjects in a 'high dose' group recognized only 20% faces correctly while the subjects in a 'placebo' and 'low dose' groups are recognized 90 %. This study implied that the intoxicated witnesses are less accurate to recognize the suspects and also less capable of describing the incidents where crime has taken place. Moreover, this study does not assert that intoxicated eyewitness is generally less trustworthy than their sober counterparts.

Keywords: intoxicated eyewitness, memory, social drinkers, lineups

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Authors: Hammadi Larbi

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The treatment of wastewater in sewage plants usually results in the formation of a large amount of sludge. These appear at the outlet of the treatment plant as a viscous fluid loaded with a high concentration of dry matter. This sludge production presents environmental, ecological, and economic risks. That is why it is necessary to find many solutions for minimizing these risks. In the present article, the effect of hydrogen peroxide, thermal treatment, and quicklime on the characteristics of the activated sludge produced in urban wastewater plant were evaluated in order to avoid any risk in the plants. The study shows increasing of the dose of H2O2 from 0 to 0.4 g causes an increase in the solubilization rate of COD from 12% to 45% and a reduction in the organic matter content of sludge (VM/SM) from 74% to 36% . The results also show that the optimum efficiency of the heat treatment corresponds to a temperature of 80 ° C for a treatment time of 40 min is 47% and 51.82% for a temperature equal to 100 ° C and 76.30 % for a temperature of 120 ° C, and 79.38% for a temperature of 140 ° C. The treatment of sludge by quicklime gives the optimum efficiency of 70.62 %. It was shown the increasing of the temperature from 80°C to 140°C, the pH of sludge was increased from 7.12 to 9.59. The obtained results showed that with increasing the dose of quicklime from 0 g/l to 1g/l in activated sludge led to an increase of their pH from 7.12 to 12.06. The study shows the increasing the dose of quicklime from 0 g/l to 1g/l causes also an increase in the solubilization of COD from 0% to 70.62 %

Keywords: activated sludge, hydrogen peroxide, thermal treatment, quicklime

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Authors: G. M. Contessa, L. Lepore, G. Gandolfo, C. Poggi, N. Cherubini, R. Remetti, S. Sandri

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Practical guidelines are provided in this work for the safe use of a portable d-t Thermo Scientific MP-320 neutron generator producing pulsed 14.1 MeV neutron beams. The neutron generator’s emission was tested experimentally and reproduced by MCNPX Monte Carlo code. Simulations were particularly accurate, even generator’s internal components were reproduced on the basis of ad-hoc collected X-ray radiographic images. Measurement campaigns were conducted under different standard experimental conditions using an LB 6411 neutron detector properly calibrated at three different energies, and comparing simulated and experimental data. In order to estimate the dose to the operator vs. the operating conditions and the energy spectrum, the most appropriate value of the conversion factor between neutron fluence and ambient dose equivalent has been identified, taking into account both direct and scattered components. The results of the simulations show that, in real situations, when there is no information about the neutron spectrum at the point where the dose has to be evaluated, it is possible - and in any case conservative - to convert the measured value of the count rate by means of the conversion factor corresponding to 14 MeV energy. This outcome has a general value when using this type of generator, enabling a more accurate design of experimental activities in different setups. The increasingly widespread use of this type of device for industrial and medical applications makes the results of this work of interest in different situations, especially as a support for the definition of appropriate radiation protection procedures and, in general, for risk analysis.

Keywords: instrumentation and monitoring, management of radiological safety, measurement of individual dose, radiation protection of workers

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Authors: Zhu Xinxin, Wang Hui, Yang Kai

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Heat flux is one of the most important test parameters in the ground thermal protection test. Slug calorimeter is selected as the main sensor measuring heat flux in arc wind tunnel test due to the convenience and low cost. However, because of excessive lateral heat transfer and the disadvantage of the calculation method, the heat flux measurement error of the slug calorimeter is large. In order to enhance measurement accuracy, the heat insulation structure and heat flux calculation method of slug calorimeter were improved. The heat transfer model of the slug calorimeter was built according to the energy conservation principle. Based on the heat transfer model, the insulating sleeve of the hollow structure was designed, which helped to greatly decrease lateral heat transfer. And the slug with insulating sleeve of hollow structure was encapsulated using a package shell. The improved insulation structure reduced heat loss and ensured that the heat transfer characteristics were almost the same when calibrated and tested. The heat flux calibration test was carried out in arc lamp system for heat flux sensor calibration, and the results show that test accuracy and precision of slug calorimeter are improved greatly. In the meantime, the simulation model of the slug calorimeter was built. The heat flux values in different temperature rise time periods were calculated by the simulation model. The results show that extracting the data of the temperature rise rate as soon as possible can result in a smaller heat flux calculation error. Then the different thermal contact resistance affecting calculation error was analyzed by the simulation model. The contact resistance between the slug and the insulating sleeve was identified as the main influencing factor. The direct comparison calibration correction method was proposed based on only heat flux calibration. The numerical calculation correction method was proposed based on the heat flux calibration and simulation model of slug calorimeter after the simulation model was solved by solving the contact resistance between the slug and the insulating sleeve. The simulation and test results show that two methods can greatly reduce the heat flux measurement error. Finally, the improved slug calorimeter was tested in the arc wind tunnel. And test results show that the repeatability accuracy of improved slug calorimeter is less than 3%. The deviation of measurement value from different slug calorimeters is less than 3% in the same fluid field. The deviation of measurement value between slug calorimeter and Gordon Gage is less than 4% in the same fluid field.

Keywords: correction method, heat flux calculation, heat insulation structure, heat transfer model, slug calorimeter

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Authors: Yuan-Hao Lee, Chia-Wei Lee, Ming-Fang Lin, Tzu-Huei Wu, Chih-Hsiang Ko, Wing P. Chan

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Computed tomography (CT) scan of the head is a good method for investigating cranial lesions. However, radiation-induced oxidative stress can be accumulated in the eyes and promote carcinogenesis and cataract. In this regard, we aimed to protect the eyes with barium sulfate shield(s) during CT scans and investigate the resultant image quality and radiation dose to the eye. Patients who underwent health examinations were selectively enrolled in this study in compliance with the protocol approved by the Ethics Committee of the Joint Institutional Review Board at Taipei Medical University. Participants’ brains were scanned with a water-based marker simultaneously by a multislice CT scanner (SOMATON Definition Flash) under a fixed tube current-time setting or automatic tube current modulation (TCM). The lens dose was measured by Gafchromic films, whose dose response curve was previously fitted using thermoluminescent dosimeters, with or without barium sulfate or bismuth-antimony shield laid above. For the assessment of image quality CT images at slice planes that exhibit the interested regions on the zygomatic, orbital and nasal bones of the head phantom as well as the water-based marker were used for calculating the signal-to-noise and contrast-to-noise ratios. The application of barium sulfate and bismuth-antimony shields decreased 24% and 47% of the lens dose on average, respectively. Under topogram-based TCM, the dose saving power of bismuth-antimony shield was mitigated whereas that of barium sulfate shield was enhanced. On the other hand, the signal-to-noise and contrast-to-noise ratios of DSCT images were decreased separately by barium sulfate and bismuth-antimony shield, resulting in an overall reduction of the CNR. In contrast, the integration of topogram-based TCM elevated signal difference between the ROIs on the zygomatic bones and eyeballs while preferentially decreasing the signal-to-noise ratios upon the use of barium sulfate shield. The results of this study indicate that the balance between eye exposure and image quality can be optimized by combining eye shields with topogram-based TCM on the multislice scanner. Eye shielding could change the photon attenuation characteristics of tissues that are close to the shield. The application of both shields on eye protection hence is not recommended for seeking intraorbital lesions.

Keywords: computed tomography, barium sulfate shield, dose saving, image quality

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Authors: Seyed Hamid Mirmohammad Sadeghi, Raffaella Sesana, Daniela Maffiodo

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This study presents a procedure for friction calculation of column electric power steering (C-EPS) system which affects handling and comfort in driving. The friction losses estimation is obtained from experimental tests and mathematical calculation. Parts in C-EPS mainly involved in friction losses are bearings and worm gear. In the theoretical approach, the gear geometry and Hertz law were employed to measure the normal load and the sliding velocity and contact areas from the worm gears driving conditions. The viscous friction generated in the worm gear was obtained with a theoretical approach and the result was applied to model the friction in the steering system. Finally, by viscous friction coefficient and Coulomb friction coefficient, values of friction in worm gear were calculated. According to the Bearing Company and the characteristics of each bearing, the friction torques due to load and due to speed were calculated. A MATLAB Simulink model for calculating the friction in bearings and worm gear in C-EPS were done and the total friction value was estimated.

Keywords: friction, worm gear, column electric power steering system, simulink, bearing, EPS

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Authors: N. V. V. S. D. Prasad

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Field experiments were conducted at Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh, India for two seasons during 2011-13 to evaluate the efficacy of flupyradifurone SL 200 a new class of insecticide in butenolide group against leaf hoppers, aphids and whitefly in Cotton. The test insecticide flupyradifurone 200 was evaluated at three doses @ 150, 200 and 250 g ai/ha ha along with imidacloprid 200 SL @ 20g ai/ha, acetamiprid 20 SP @ 20g ai/ha, thiamethoxam 25 WG @ 25g ai/ha and monocrotophos 36 SL @ 360 g ai/ha as standards. Flupyradifurone SL 200 even at lower dose of 150g ai/ha exhibited superior efficacy against cotton leafhopper, Amrasca devastans than the neonicotinoids which are widely used for control of sucking pests in cotton. Against cotton aphids, Aphis gossypii. Flupyradifurone SL 200 @ 200 and 250 g ai/ha ha was proved to be effective and the lower dose @ 150g ai/ha performed better than some of the neonicotinoids. The effect of flupyradifurone SL 200 on cotton against whitefly, Bemisia tabaci was evident at higher doses of 200 and 250 g ai/ha and superior to all standard treatments, however, the lower dose is at par with neonicotinoids. The seed cotton yield of flupyradifurone 200 SL at all the doses tested was superior than imidacloprid 200 SL @ 20g ai/ha and acetamiprid 20 SP @ 20g ai/ha. There is no significant difference among the insecticidal treatments with regards to natural enemies. The results clearly suggest that flupyradifurone is a new tool to combat sucking pest problems in cotton and can well fit in IRM strategies in light of wide spread insecticide resistance in cotton sucking pests.

Keywords: cotton, flupyradifurone, neonicotinoids, sucking pests

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Authors: Ava Zarif Sanayei, Sedigheh Sina

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During fluoroscopically guided procedures, healthcare workers, especially radiology trainees, are at risk of exposure to elevated radiation exposure. It is vital to prioritize their safety in such settings. However, there is limited data on their monthly or annual doses. This study aimed to evaluate the equivalent dose to the eyes of the student trainee, utilizing LiF: Mg, Ti (TLD-100) chips at the radiology department of a hospital in Shiraz, Iran. Initially, the dosimeters underwent calibration procedures with the assistance of ISO-PTW calibrated phantoms. Following this, a set of dosimeters was prepared To determine HP(3) value for a trainee involved in the main operation room and controlled area utilized for two months. Three TLD chips were placed in a holder and attached to her eyeglasses. Upon completion of the duration, the TLDs were read out using a Harshaw TLD reader. Results revealed that Hp(3) value was 0.31±0.04 mSv. Based on international recommendations, students in radiology training above 18 have an annual dose limit of 0.6 rem (6 mSv). Assuming a 12-month workload, staff radiation exposure stayed below the annual limit. However, the Trainee workload may vary due to different deeds. This study's findings indicate the need for consistent, precise dose monitoring in IR facilities. Students can undertake supervised internships for up to 500 hours, depending on their institution. These internships take place in health-focused environments offering radiology services, such as clinics, diagnostic imaging centers, and hospitals. Failure to do so might result in exceeding occupational radiation dose limits. A 0.5 mm lead apron effectively absorbs 99% of radiation. To ensure safety, technologists and staff need to wear this protective gear whenever they are in the room during procedures. Furthermore, maintaining a safe distance from the primary beam is crucial. In cases where patients need assistance and must be held for imaging, additional protective equipment, including lead goggles, gloves, and thyroid shields, should be utilized for optimal safety.

Keywords: annual dose limits, Hp(3), individual monitoring, radiation protection, TLD-100

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Authors: Eltayeb Hamad Elneel Yousif

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This paper describes occupational radiation doses of workers in non-destructive testing (NDT) and some medical practices during the year 2007. The annual doses received by the workers of a public hospital are presented in this report. The Department is facilitated with HARSHAW Reader model 6600 and assigned the rule of personal monitoring to contribute in controlling and reducing the doses received by radiation workers. TLD cards with two TLD chips type LiF: Mg, Ti (TLD-100) were calibrated to measure the personal dose equivalent Hp(10). Around 150 medical radiation workers were monitored throughout the year. Each worker received a single TLD card worn on the chest above lead apron and returned for laboratory reading every two months. The average annual doses received by the workers of radiotherapy, nuclear medicine and diagnostic radiology were evaluated. The annual doses for individual radiation workers ranged between 0.55-4.42 mSv, 0.48-1.86 mSv, and 0.48-0.91 mSv for the workers of radiotherapy, nuclear medicine and diagnostic radiology, respectively. The mean dose per worker was 1.29±1, 1.03±0.4, and 0.69±0.2 mSv, respectively. The results showed compliance with international dose limits. Our results reconfirm the importance of personal dosimetry service in assuring the radiation protection of medical staff in developing countries.

Keywords: radiation medicine, non-destructive testing, TLD, public hospital

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Authors: S. Boorboor, S. A. H. Feghhi, H. Jafari

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The ionizing radiations cause different kinds of damages in electronic components. MOSFETs, most common transistors in today’s digital and analog circuits, are severely sensitive to TID damage. In this work, the threshold voltage shift of CD4007 device, which is an integrated circuit including P-channel and N-channel MOS transistors, was investigated for low dose gamma irradiation under different gate bias voltages. We used linear extrapolation method to extract threshold voltage from I_D-V_G characteristic curve. The results showed that the threshold voltage shift was approximately 27.5 mV/Gy for N-channel and 3.5 mV/Gy for P-channel transistors at the gate bias of |9 V| after irradiation by Co-60 gamma ray source. Although the sensitivity of the devices under test were strongly dependent to biasing condition and transistor type, the threshold voltage shifted linearly versus accumulated dose in all cases. The overall results show that the application of CD4007 as an electronic buffer in a radiation therapy system is limited by TID damage. However, this integrated circuit can be used as a cheap and sensitive radiation dosimeter for accumulated dose measurement in radiation therapy systems.

Keywords: threshold voltage shift, MOS transistor, linear extrapolation, gamma irradiation

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Authors: A. H. Jagaba, Musa Babayo, Ab Aziz Abdul Latiff, Sule Abubakar, I. M. Lawal, Isa Zubairu, M. A. Nasara

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Wastewater containing heavy metals is of extreme importance globally because of its potential threat to both the aquatic ecosystem and the soil environment. Heavy metal is hazardous even at low concentration and thereby causing various forms of diseases. One method which has been tested and found to be effective for heavy metals removal is coagulation-flocculation. For the coagulation process of POME obtained from Pertubuhan Peladang Negeri Johor (PPNJ), Oil Palm Mill Company located in Kahang area of Kluang, Johor Darul Takzim, Malaysia, diffèrent coagulants would be used to absorb and then separate the metals from wastewater. The determination of heavy metals concentration in POME was carried out using an inductively coupled plasma (ICP) and an Atomic Absorption Spectrometer (AAS). Results of the study showed that alum coagulant was successful in effectively reducing Cu, Cd, and Mn from 0.840 mg/l, 0.00509 mg/l and 8.191 mg/l to as low as 0.107 mg/l, 0.000270 mg/l and 0.612 mg/l respectively. All were obtained at a dose of 1000 mg/l. 1000 mg/l dose of ferric chloride reduced Pb concentration from 0.0248 mg/l to 0.00151 mg/l. Chitosan was best at reducing Fe and Zn from 62.91 mg/l and 3.616 mg/l to 6.003 mg/l and 0.595 mg/l all at a dose of 400 mg/l.

Keywords: palm oil mill effluent, coagulation, heavy metals, Pertubuhan Peladang Negeri Johor, Malaysia

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Authors: Khalid A. Salman, Shereen Wagih, Tariq Munshi, Musaed Almalki, Safwan Zatari, Zahid Khan

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Aim: To measure exposure levels to family members and caregivers of Saudi patients treated with low dose I131 therapy, and household radiation exposure rate to predict different factors that can affect radiation exposure. Patients and methods: All adult self dependent patients with hyperthyroidism or cancer thyroid referred for low dose radioactive I131 therapy on outpatient basis are included. Radiation protection procedures are given to the participant and family members in details. TLD’s were dispensed to each participant in sufficient quantity for his/her family members living in the household. TLD’s are collected at fifth days post-dispense from patients who agreed to have a home visit during which the household is inspected and level of radiation contamination of surfaces was measured. Results: Thirty-two patients were enrolled in the current study, with a mean age of 43.1± 17.1 years Out of them 25 patients (78%) are females. I131 therapy was given in twenty patients (63%) for cancer thyroid of and for toxic goiter in the remaining twelve patients (37%), with an overall mean I131 dose of 24.1 ± 7.5mCi that is relatively higher in the former. The overall number of household family members and helpers of patients are 139, out of them77 are females (55.4%) & 62 are males (44.6%) with a mean age of 29.8± 17.6. The mean period of contact with the patient is 7.6 ±5.6hours. The cumulative radiation exposure shows that radiation exposure to all family members is below the exposure constraint (1mSv), with a range of 109 to 503uSv, and a mean value of 220.9±91 uSv. Numerical data shows a little higher exposure rate for family members of those who receive higher dose of I131 (patients with thyroid cancer) and household members who spent longer time with the patient, yet, the difference is statistically insignificant (P>0.05). Besides, no significant correlation was found between the degree of cumulative exposure of the family members to their gender, age, socioeconomic standard, educational level and residential factors. In the 21 home visits all data from bedrooms, reception areas and kitchens are below hazardous limits (0.5uSv/h) apart from bathrooms that give a slightly higher reading of 0.57±0.39 uSv/h in those with cancer thyroid who receive a higher radiation dose. A statistically significant difference was found between radiation exposure rate in bathrooms used by the patient versus those used by family members only, with a mean value of exposure rate of 0.701±0.21 uSv/h and 0.17±0.82 uSv/h respectively, with a p-value of 0.018 (<0.05). Conclusion: Family members of patients treated with low dose I131 on outpatient basis have a good compliance to radiation protection instruction if given properly with a cumulative radiation exposure rate evidently beyond the radiation exposure constraints of 1 mSv. Given I131 dose, hours spent with the patient, age, gender, socioeconomic standard, educational level and residential factors have no significant correlation with the cumulative radiation exposure. The patient bathroom exhibits more radiation exposure rate, needing more strict instructions for patient bathroom use and health hygiene.

Keywords: family members, radiation exposure, radioactive iodine therapy, radiation safety

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Authors: Tatiana V. Melnikova, Lyudmila P. Polyakova, Alla A. Oudalova

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As a result of environmental pollution, the production of agriculture and foodstuffs inevitably contain residual amounts of Persistent Organic Pollutants (POP). The special attention must be given to organic pollutants, including various organochlorinated pesticides (OCP). Among priorities, OCP is DDT (and its metabolite DDE), alfa-HCH, gamma-HCH (lindane). The control of these substances spends proceeding from requirements of sanitary norms and rules. During too time often is lost sight of that the primary product can pass technological processing (in particular irradiation treatment) as a result of which transformation of physicochemical forms of initial polluting substances is possible. The goal of the present work was to study the OCP radiation degradation at a various gamma-radiation dosimetric characteristics. The problems posed for goal achievement: to evaluate the content of the priority of OCPs in food; study the character the degradation of OCP in model solutions (with micro concentrations commensurate with the real content of their agricultural and food products) depending upon dosimetric characteristics of gamma-radiation. Qualitative and quantitative analysis of OCP in food and model solutions by gas chromatograph Varian 3400 (Varian, Inc. (USA)); chromatography-mass spectrometer Varian Saturn 4D (Varian, Inc. (USA)) was carried out. The solutions of DDT, DDE, alpha- and gamma- isomer HCH (0.01, 0.1, 1 ppm) were irradiated on "Issledovatel" (60Co) and "Luch - 1" (60Co) installations at a dose 10 kGy with a variation of dose rate from 0.0083 up to 2.33 kGy/sec. It was established experimentally that OCP residual concentration in individual samples of food products (fish, milk, cereal crops, meat, butter) are evaluated as 10-1-10-4 mg/kg, the value of which depends on the factor-sensations territory and natural migration processes. The results were used in the preparation of model solutions OCP. The dependence of a degradation extent of OCP from a dose rate gamma-irradiation has complex nature. According to our data at a dose 10 kGy, the degradation extent of OCP at first increase passes through a maximum (over the range 0.23 – 0.43 Gy/sec), and then decrease with the magnification of a dose rate. The character of the dependence of a degradation extent of OCP from a dose rate is kept for various OCP, in polar and nonpolar solvents and does not vary at the change of concentration of the initial substance. Also in work conditions of the maximal radiochemical yield of OCP which were observed at having been certain: influence of gamma radiation with a dose 10 kGy, in a range of doses rate 0.23 – 0.43 Gy/sec; concentration initial OCP 1 ppm; use of solvent - 2-propanol after preliminary removal of oxygen. Based on, that at studying model solutions of OCP has been established that the degradation extent of pesticides and qualitative structure of OCP radiolysis products depend on a dose rate, has been decided to continue researches radiochemical transformations OCP into foodstuffs at various of doses rate.

Keywords: degradation extent, dosimetric characteristics, gamma-radiation, organochlorinated pesticides, persistent organic pollutants

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Authors: Ahmed Ferhati, Arezki Adjrad, Ratiba Mitiche-Kettab, Hakim Djafer Khodja

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The porous media are omnipresent around us that they are natural as sand, clay, rocks, or manufactured like concretes, cement, and ceramics. The variety of porous environment indicates a wide material range which can be very different from each other. Their common point is to be made up of a solid matrix and a porous space. In our case of study, we made the modeling of the flows in porous environments through the massives as in the case of an earth dam. The computer code used (PLAXIS) offer the possibility of modeling of various structures, in particular, the works in lands because that it deals with the pore water pressure due to the underground flow and the calculation of the plastic deformations. To confirm results obtained by PLAXIS, GeoStudio SEEP/W code was used. This work treats modeling of flows and mechanical and hydraulic behavior of earth dam. A general framework which can fit the calculation of this kind of structures and the coupling of the soil consolidation and free surface flows was defined. In this study; we have confronted a real case modeling of an earth dam. It was shown, in particular, that it is possible to entirely lead the calculation of real dam and to get encouraging results from the hydraulic and mechanical point of view.

Keywords: analyzes, dam, flow, modeling, PLAXIS, seep/w, slope

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Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova

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Objectives. Gastrointestinal involvement is one of the most common manifestations of systemic sclerosis (SSc). The aim of our study was to assess the frequency of gastrointestinal manifestations in SSc patients (pts) with interstitial lung disease (ILD) and their changes to rituximab (RTX) therapy. Methods. There were 103 pts with SSc in this study. The mean follow-up period was 12.6±10.7 months. The mean age was 47±12.9 years, females - 87 pts (84%), and the diffuse cutaneous subset of the disease 55 pts (53%). The mean disease duration was 6.2±5.5 years. All pts had ILD and were positive for ANA. 67% of them were positive for anti-topoisomerase-1. All patients received prednisolone at a dose of 11.3±4.5 mg/day, and immunosuppressants at inclusion received 47% of them. Pts received RTX due to the ineffectiveness of previous therapy for ILD. The cumulative mean dose of RTX was 1.7±0.6 grams. 90% of pts received omeprazole at a dose of 20-40 mg/day. Results. At inclusion, dysphagia was observed in 76 pts (74%), early satiety or vomiting in 32 pts (31%), and diarrhea in 20 pts (19%). We didn't observe any changes in gastrointestinal manifestation during RTX therapy. There was a decrease in the number of pts with dysphagia from 76 (74%) to 66 (64%), but it was insignificant. The number of pts with early satiety or vomiting and diarrhea didn't change. Conclusion. In our study, gastrointestinal involvement was observed in most of the pts with SSc-ILD. We didn't find any significant changes in gastrointestinal manifestations during RTX therapy. RXT does not worsen gastrointestinal manifestations in SSc-ILD.

Keywords: systemic sclerosis, dysphagia, rituximab, gastrointestinal manifestations

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Authors: Eunsu Jang, Kang Park

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In developing an armored ground combat vehicle (AGCV), it is a very important step to analyze the vulnerability (or the survivability) of the AGCV against enemy’s attack. In the vulnerability analysis, the penetration equations are usually used to get the penetration depth and check whether a bullet can penetrate the armor of the AGCV, which causes the damage of internal components or crews. The penetration equations are derived from penetration experiments which require long time and great efforts. However, they usually hold only for the specific material of the target and the specific type of the bullet used in experiments. Thus, penetration simulation using ANSYS can be another option to calculate penetration depth. However, it is very important to model the targets and select the input parameters in order to get an accurate penetration depth. This paper performed a sensitivity analysis of input parameters of ANSYS on the accuracy of the calculated penetration depth. Two conflicting objectives need to be achieved in adopting ANSYS in penetration analysis: maximizing the accuracy of calculation and minimizing the calculation time. To maximize the calculation accuracy, the sensitivity analysis of the input parameters for ANSYS was performed and calculated the RMS error with the experimental data. The input parameters include mesh size, boundary condition, material properties, target diameter are tested and selected to minimize the error between the calculated result from simulation and the experiment data from the papers on the penetration equation. To minimize the calculation time, the parameter values obtained from accuracy analysis are adjusted to get optimized overall performance. As result of analysis, the followings were found: 1) As the mesh size gradually decreases from 0.9 mm to 0.5 mm, both the penetration depth and calculation time increase. 2) As diameters of the target decrease from 250mm to 60 mm, both the penetration depth and calculation time decrease. 3) As the yield stress which is one of the material property of the target decreases, the penetration depth increases. 4) The boundary condition with the fixed side surface of the target gives more penetration depth than that with the fixed side and rear surfaces. By using above finding, the input parameters can be tuned to minimize the error between simulation and experiments. By using simulation tool, ANSYS, with delicately tuned input parameters, penetration analysis can be done on computer without actual experiments. The data of penetration experiments are usually hard to get because of security reasons and only published papers provide them in the limited target material. The next step of this research is to generalize this approach to anticipate the penetration depth by interpolating the known penetration experiments. This result may not be accurate enough to be used to replace the penetration experiments, but those simulations can be used in the early stage of the design process of AGCV in modelling and simulation stage.

Keywords: ANSYS, input parameters, penetration depth, sensitivity analysis

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Authors: G. Chakhaia, S. Gogilava, L. Tsulukidze, Z. Laoshvili, I. Khubulava, S. Bosikashvili, T. Gugushvili

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The work reviewed and evaluated various genesis debris flow phenomena recently formatted in the Mletiskhevi, accordingly it revealed necessity of treatment modern debris flow against measures. Based on this, it is proposed the debris flow against truncated semi cone shape construction, which elements are contained in the car’s secondary tires. its constituent elements (sections), due to the possibilities of amortization and geometric shapes is effective and sustainable towards debris flow hitting force. The construction is economical, because after crossing the debris flows in the river bed, the riverbed is not cleanable, also the elements of the building are resource saving. For assessment of influence of cohesive debris flow at the construction and evaluation of the construction effectiveness have been implemented calculation in the specific assumptions with approved methodology. According to the calculation, it was established that after passing debris flow in the debris flow construction (in 3 row case) its hitting force reduces 3 times, that causes reduce of debris flow speed and kinetic energy, as well as sedimentation on a certain section of water drain in the lower part of the construction. Based on the analysis and report on the debris flow against construction, it can be said that construction is effective, inexpensive, technically relatively easy-to-reach measure, that’s why its implementation is prospective.

Keywords: construction, debris flow, sections, theoretical calculation

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Authors: Azza T. Tahera, Eman M. Ahmeda, Nadia A. Khalila, Yassin M. Nissanb

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New 3-(pyridin-4-yl)-[1,2,4] triazolo [4,3-b] pyridazine derivatives 2a-i, 4a,b and 6a,b were designed, synthesized and evaluated as cytotoxic agents. All compounds were investigated for their in vitro cytotoxicity at a single dose 10-5M concentration towards 60 cancer cell lines according to USA NCI protocol. The preliminary screening results showed that the majority of tested compounds exhibited remarkable activity against SR (leukemia) cell panel. Molecular docking for all synthesized compounds was performed on the active site of c-Met kinase. The most active compounds, 2f and 4a were further evaluated at a seven dose level screening and their IC50 as a c-Met kinase inhibitors were determined in vitro.

Keywords: triazolopyridazines, pyridazines, cytotoxic activity, cell panel

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Authors: Huma Shareef, Ghazala H. Rizwani, Ahsana Dar

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In traditional medicine Cardiospermum halicacabum L. (Sapindeaceae) is used against various ailments. In current investigation searching a new remedy that will available easily, non expensive, able to lower hypertension and standardize blood pressure, made us to develop an herbal medicine. Crude ethanol extract of C. halicacabum and its various fractions ethyl acetate and butanol showed a dose-dependent hypotensive effect in anaesthetized rats. The trachea was exposed and freed from connective tissue and incubated by cannula to facilitate spontaneous respiration. The right carotid artery and left jugular vein were cannulated with polyethylene tubing PE-50 for monitoring blood pressure changes via pressure transducer (Gould P23 ID) connected to a Grass model 79D polygraph and for i.v. injection, respectively. Drugs or the plant extracts were administered at a constant volume of 0.5 ml/kg, followed by injection of 0.2 ml of saline that flushed the cannula. Systolic, diastolic and mean arterial blood pressure (MABP) was measured in mm Hg and heart rate in beats/min. Ethanol extract of C. halicacabum showed a significant activity at 50 mg/kg dose. Ethyl acetate fraction (10, 20, 30, 40, and 50 mg/kg) induced dose dependent fall in systolic and diastolic blood pressure, heart rate of rats. At 10-30 mg/kg the hypotensive effect was non significantly reduced by 10 -15%. However, the extract at 40 mg/kg induced significant hypotensive effect calculated as 30.95±3.2% MABP and this effect persists till 50 mg/kg. The higher polar fraction (butanol) of the whole plant failed to produce any significant response against MABP at all the tested doses (10-50 mg/kg). C. halicacabum lowers blood pressure, exerts a dose-dependent hypotensive effect, can be used as hypotensor.

Keywords: cardiospermum halicacabum, calcium channel blocker, hypotensive, various extracts

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Authors: Hamidreza Jabal Ameli, Anahita Movahedi

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Purpose: In radionuclide therapy, radioactive atoms are coupled to monoclonal antibodies (mAbs) for treating cancer tumor while limiting radiation to healthy tissues. We know that tumoral and normal tissues are not equally sensitive to radiation. In fact, biological effects such as cellular repair processes or the presence of less radiosensitive cells such as hypoxic cells should be taken account. For this reason, in this paper, we want to calculate biological effect dose (BED) inside tumoral area and healthy cells around tumors. Methods: In this study, deposited doses of a radionuclide, gold-198, inside cells lattice and surrounding healthy tissues were calculated with Monte Carlo method. The elemental compositions and density of malignant and healthy tissues were obtained from ICRU Report 44. For reaching to real condition of oxygen effects, the necrosis and hypoxia area inside tumors has been assessed. Results: With regard to linear-quadratic expression which was defined in Monte Carlo, results showed that a large amount of BED is deposited in the well-oxygenated part of the hypoxia area compared to necrosis area. Moreover, there is a significant difference between the curves of absorbed dose with BED and without BED.

Keywords: biological dose, monte carlo, hypoxia, radionuclide therapy

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Authors: Seyed Habib A. Rahmati, Mohamad Hasan Sadeghpour, Parsa Fallah Sheikhlari

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Location quotient (LQ) is a comparison technique that represents emphasized economic structure of single zone versus the standard area to identify specialty for every zone. In another words, the exact calculation of this metric can show the main core competencies and critical capabilities of an area to the decision makers. This research focus on the exact calculation of the LQ for an Iranian Province called Qazvin and within a case study introduces LQ of the capable industries of Qazvin. Finally, through different graphs and tables, it creates an opportunity to compare the recognized capabilities.

Keywords: location quotient, case study, province analysis, core competency

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Authors: Sophio Kalmakhelidze, Eka Shekiladze, Tamar Sanikidze, Mikheil Gogebashvili, Nazi Ivanishvili

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Radiation-induced various degrees of brain injury and cognitive impairment have been described after cranial radiotherapy of brain tumors. High doses of ionizing radiation have a severe impact on the central nervous system, resulting in morphological and behavioral impairments. Structures of the limbic system are especially sensitive to radiation exposure. Hence, compounds or drugs that can reduce radiation-induced impairments can be used as promising antioxidants or radioprotectors. In our study Mice whole-body irradiation with 137Cs was performed at a dose rate of 1,1 Gy/min for a total dose of 5 Gy with a “Gamma-capsule-2”. Irradiated mice were treated with Herniarin (20 mg/kg) for five days before irradiation and the same dose was administrated after one hour of irradiation. The immediate and delayed effects of ionizing radiation, as well as, protective effect of Herniarin was evaluated during early and late post-irradiation periods. The results reveal that ionizing radiation (5 Gy) alters the structure of the hippocampus in adult mice during the late post-irradiation period resulting in the decline of memory formation and learning process. Furthermore, Simple Coumarin-Herniarin reveals a radiosensitizing effect reducing morphological and behavioral alterations.

Keywords: ionizing radiation, cognitive impairments, hippocampus, limbic system, Herniarin

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Authors: Fatimah A. Alhomaid, Nadia H. Mahmoud, Maha A. Al-Qaraawi

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The present study was designed to induce hyperhomocysteinemia (HHcy) in elderly male and female rats. Also,to evaluate, the effect of (HHcy) as a risk factor for cerebrovascular disease and brain atrophy and folate supplementation on serum levels of Hcy, total cholesterol, low density lipoprotein cholesterol (LDLc), high density lipoprotein cholesterol (HDLc), triglycerides, pyridoxal phosphate , folate also, histopathological examination of brain and cerebrovascular vessels In this work 50 male and 50 female elderly albino rats were used and divided into five groups. The first group served as control, the second and third group received two different dose of L-methionine, the fourth and fifth group received fortified diet with folate powder plus L-methionine. Our results showed that homocysteine levels in male and female rats that received low and high dose of methionine were higher than in the control group, while the levels of folate significantly decreased in male rats only. Induced hyperhomocysteinemia in elderly male and female rats led to significant increase in serum level of cholesterol, LDLc and triglycerides but serum level of HDLc were significantly lower in methionine treated male and female rats than in control. Our results showed that a strong positive correlation between all these parameters and homocysteine except HDLc levels which correlate negatively to Hcy levels. Administration of folate to methionine treated male rats led to insignificant changes in the level of cholesterol when compared to control group but this level was found to be significantly decrease in female rats received small dose of methionine. When the level of cholesterol compared to the same dose of methionine treated group we found a significant decrease in both male and female rats. LDLc and triglycerides level significantly decrease in male rats only versus the control rats, while when compared to low and high dose of methionine a significant decreased occurs. A significant increase in serum level of HDLc in male and female rats when compared to both control and methionine treated groups. In male and female rats supplemented with folate we found an increased serum levels of folate when compared to rats received both dose of methionine. The levels of pyridoxal phosphate significantly decreased in all treated rats compared to the control group and its level were increased with supplementation of folate versus the rats received small and large dose of methionine. It can be concluded that hyperhomocysteinemia may be an additional risk factor for cerebrovascular atherosclesosis and brain atrophy in elderly people and diatery supplementation with folate blocking the activity of homocysteine and may be considered as a therapeutic possibility.

Keywords: hyperhomocysteinemia, brain atrophy, cerebrovascular, L-methionine, pyridoxal phosphate

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Authors: Anna-Caroline Lavergne-Bril, Jean-François Colin, David Peralta, Pascale Maldivi

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Cobalt is a critical material, widely used in Li-ion batteries. Due to the planned electrification of European vehicles, cobalt needs are expending – and resources are limited. To meet the needs in cobalt to come, it is necessary to develop new efficient ways to recycle cobalt. One of the biggest sources comes from old electrical vehicles batteries (batteries sold in 2019: 500 000 tons of waste to be). A closed loop process of cobalt recycling has been developed and this presentation aims to present the selectivity mechanism of cobalt over manganese and nickel in solution. Cobalt precipitation as a ZIF material (Zeolitic Imidazolate framework) from a starting solution composed of equimolar nickel, manganese and cobalt is studied. A 2-MeIm (2-methylimidazole) linker is introduced in a multimetallic Ni, Mn, Co solution and the resulting ZIF-67 is 100% pure Co among its metallic centers. Selectivity of Co over Ni is experimentally studied and DFT modelisation calculation are conducted to understand the geometry of ligand-metal-solvent complexes in solution. Selectivity of Co over Mn is experimentally studied, and DFT modelisation calcucation are conducted to understand the link between pKa of the ligand and precipitration of Mn impurities within the final material. Those calculation open the way to other ligand being used in the same process, with more efficiency. Experimental material are synthetized from bimetallic (Ni²⁺/Co²⁺, Mn²⁺/Co²⁺, Mn²⁺/Ni²⁺) solutions. Their crystallographic structure is analysed by XRD diffraction (Brüker AXS D8 diffractometer, Cu anticathode). Morphology is studied by scanning electron microscopy, using a LEO 1530 FE-SEM microscope. The chemical analysis is performed by using ICP-OES (Agilent Technologies 700 series ICP-OES). Modelisation calculation are DFT calculation (density functional theory), using B3LYP, conducted with Orca 4.2.

Keywords: MOFs, ZIFs, recycling, closed-loop, cobalt, li-ion batteries

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Authors: Ali Faisal Saleem, Farheen Quadri, Mach Ondrej, Anita Zaidi

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Purpose: Pakistan is the final frontier for a polio-free world. Chronic malnutrition is associated with lack of effective gut immunity, and possibly associated with poliomyelitis in children received multiple OPV. We evaluate IPV dose administered together with OPV results in higher immunogenicity and mucosal immunity compared to OPV alone in chronically malnourished infants. Methods AND Materials: A community-based, unblinded-randomized-trial, conducted in 5 peri-urban, low-middle-income households of Karachi, in infants 9-12 months. Two study groups were non-malnourished (HAZ= -2 or more) and chronic malnourished (HAZ <-2SD), with 2-arms each i) OPV and ii) OPV and IPV. Two blood specimens (2ml) at baseline and at day 28 and two stool specimens (6 gm.) at day 29 and after 7 days. All infants received a bOPV challenge dose after first stool specimen. Calculates sample size was 210 in each arm. Serological (baseline compared to 28 days post-vaccine) and mucosal immunity after one week of bOPV challenge dose were study outcomes. Results: Baseline seroprevalence in malnourished infants were low compared to non-malnourished (P1, P2 and P3 (p=<0.001). There is significant rise in antibody titer and P1 seroprevalence in Mal A and B after receiving study vaccine; much higher in Mal B. Infants randomized to bOPV + IPV study vaccine showed incremental immune response against P1 (Mal B, 92.2%; Nor B, 98.4%), P2 (Mal B, 90.4%; Nor B, 94.7%), and P3 (Mal B, 85.6% and Nor B, 93.5%) was observed. A significant proportion of infants in malnourished (P1, 13%; P2, 24%; P3, 26%) and normally nourished group (P1, 5%; P2, 11%; P3, 14%) were found to be seronegative at baseline. Infants who received BOPV + IPV as their study vaccine showed a very high seroconversion response after vaccine (p=<0.001 for P1, P2 and P3). Majority of the specimens were negative at baseline (Mal A, 2%, Mal B, 1%; Nor A, 2%; Nor B, 1%), and remains negative after bOPV challenge dose (Mal A, 8%, Mal B, 6%; Nor A, 11%; Nor B, 10%). Conclusion: Malnourished-infants have low poliovirus-seroprevalence that increased remarkably after IPV. There is less viral shedding after IPV in infants.

Keywords: chronic malnutrition, infants, IPV, OPV

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Authors: Ounassa Adjroud

Abstract:

Potassium dichromate (K2Cr2O7) is one of the most toxic elements to which man can be exposed at work or in the environment. The purpose of the current work is to compare the effect of K2Cr2O7 using variations in the dose, route of administration and duration of exposure in male and female Wistar albino rats with a special focus on biochemical parameters. K2Cr2O7 was subcutaneously administered alone (10, 50 and 100 mg/kg body weight) to female Wistar albino rats. Male rats received in their drinking water K2Cr2O7 30 mg/L/day) for 20 consecutive days. The Biochemical parameters were evaluated on days 3, 6 and 21 after subcutaneous (sc.) treatment in female rats and on days 10 and 20 after oral administration in male rats. The subcutaneous (s.c.) administration of 25 mg/kg of K2Cr2O7 to Wistar albino rats induced a slight change in plasma glucose levels during the experiment period. On the contrary, a significant decrease in plasma glucose levels was observed with 50 mg/kg mainly on days 3 (-26%) and 21 (-48%) after treatment compared to controls females rats. On the other hand, the higher dose provoked a significant increase in plasma glucose concentrations on days 6 (+31%) and 21 (+60%). similarly, the lower dose of chromium had no effect on the plasma urea levels. Conversely, a significant increase (122%) in this parameter was obtained during the first three days after treatment. In addition, a significant decrease in plasma glucose levels was observed with 50 mg/kg mainly on days 3 (-26%) and 21 (-48%) after treatment. On the other hand, the higher dose provoked a significant increase in plasma glucose concentrations on days 6 (+31%) and 21 (+60%). similarly, the lower dose of chromium had no effect on the plasma urea levels. Conversely, a significant increase in this parameter (122%) was obtained during the first three days after treatment. In addition, administration of 100 mg/kg of K2Cr2O7 by s.c markedly augmented the levels of plasma urea on days 3 (62%) and 6 (121%). Administration of 30 mg/L/day of K2Cr2O7 in the drinking water induced a significant augmentation in both of plasma glucose (27%) and urea (126%) during the first ten days of treatment. These results suggested that K2Cr2O7 administered subcutaneously or in the drinking water may induce harmful effects on biochemical parameters.

Keywords: glucose, potassium dichromate, Wistar albino rat, urea

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Authors: Yousif Mohamed Y. Abdallah, Khalid H. Eltom

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This is an experimental study deals with measurement of the periodic physiological organ motion during lung external irradiation in order to reduce the exposure of healthy tissue during radiation treatments. The results showed for left lung displacement reading (4.52+1.99 mm) and right lung is (8.21+3.77 mm) which the radiotherapy physician should take suitable countermeasures in case of significant errors. The motion ranged between 2.13 mm and 12.2 mm (low and high). In conclusion, the calculation of tumour mobility can improve the accuracy of target areas definition in patients undergo Sterostatic RT for stage I, II and III lung cancer (NSCLC). Definition of the target volume based on a high resolution CT scan with a margin of 3-5 mm is appropriate.

Keywords: physiological motion, lung, external irradiation, radiation medicine

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Authors: Ava Zarif Sanayei, Sedigheh Sina

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Interventional radiology (IR) uses imaging guidance, including X-rays and CT scans, to deliver therapy precisely. Most IR procedures are performed under local anesthesia and start with a small needle being inserted through the skin, which may be called pinhole surgery or image-guided surgery. There is increasing concern about radiation exposure during interventional radiology procedures due to procedure complexity. The basic aim of optimizing radiation protection as outlined in ICRP 139, is to strike a balance between image quality and radiation dose while maximizing benefits, ensuring that diagnostic interpretation is satisfactory. This study aims to estimate the equivalent doses to the main trunk of the body for the Interventional radiologist and Superintendent using LiF: Mg, Ti (TLD-100) chips at the IR department of a hospital in Shiraz, Iran. In the initial stage, the dosimeters were calibrated with the use of various phantoms. Afterward, a group of dosimeters was prepared, following which they were used for three months. To measure the personal equivalent dose to the body, three TLD chips were put in a tissue-equivalent batch and used under a protective lead apron. After the completion of the duration, TLDs were read out by a TLD reader. The results revealed that these individuals received equivalent doses of 387.39 and 145.11 µSv, respectively. The findings of this investigation revealed that the total radiation exposure to the staff was less than the annual limit of occupational exposure. However, it's imperative to implement appropriate radiation protection measures. Although the dose received by the interventional radiologist is a bit noticeable, it may be due to the reason for using conventional equipment with over-couch x-ray tubes for interventional procedures. It is therefore important to use dedicated equipment and protective means such as glasses and screens whenever compatible with the intervention when they are available or have them fitted to equipment if they are not present. Based on the results, the placement of staff in an appropriate location led to increasing the dose to the radiologist. Manufacturing and installation of moveable lead curtains with a thickness of 0.25 millimeters can effectively minimize the radiation dose to the body. Providing adequate training on radiation safety principles, particularly for technologists, can be an optimal approach to further decreasing exposure.

Keywords: interventional radiology, personal monitoring, radiation protection, thermoluminescence dosimetry

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