investigation into the potential applicability of gel dosimeters for dosimetry in boron neutron capture therapy

The aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate [or PMMA], A150 plastic and TE- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. Thermal neutron fluence, photon dose and epithermal neutron dose distributions were computed for the epithermal neutron beam of the optimized linac based BNCT. Amongst all investigated phantom materials, TE-liquid was shown to be a better substitute for brain tissue than other phantom materials. The differences between TE- liquid and brain at the depth of 6.1 cm for thermal neutron fluence, gamma dose and epithermal neutron dose distributions was calculated 2.80%, 2.40% and -13.87%, respectively. In comparison with the other gel dosimeters, LMD2 provided a better simulation of radiation transport in the brain. It's results differed from the real brain, at the depth of 6.1 cm, for thermal neutron fluence, gamma dose and epithermal neutron dose distributions, by -1.27%, 4.20% and 21.05% respectively. Even though, in gamma dose distribution the LMD2 has large deviation from brain tissue distribution, the deviation is approximately independent of depth, so the results can be multiplied by a constant coefficient to be more consistent with reality. Even though, TE- liquid showed satisfactory results for brain tissue substitution in BNCT, but some properties of gel dosimeters such as three dimensionality, make LMD2 a potentially good dosimeter for dosimetric verification in BNCT

[Serum protein alterations in goats naturally infected with Babesia ovis]

This study was conducted to determine the electrophoretic pattern of serum protein in goats infected with Babesia ovis. Serum total protein was calculated and serum electrophoresis from 15 goats naturally infected with B. ovis as well as same number of healthy goats was performed. Microscopic examination of Giemsa-stained peripheral blood smears revealed B. ovis infection. The parasitological diagnosis was confirmed using polymerase chain reaction [PCR] assay by using a pair of B. ovis-specific primers. Mean values total protein and alpha and gama globulin fractions in infected goats were significantly higher [P<0.05] than those observed in the healthy group

[Sensory evaluation and assessment of compliance with vitamin D and Calcium fortified- milk among school- age children in Tehran]

Inadequate intake of Calcium and vitamin D is one of the common health problems, especially among the children in developed as well as developing countries, including Iran. Fortification of foodstuff, specially milk and dairy products, is being used as a major strategy to combat this problem in many countries. This study aimed to evaluate sensory desirability and compliance with vitamin D and Calcium-fortified milk, among 9-11 year-old schoolchildren in the city of Tehran. This cross sectional study was conducted in two phases including sensory evaluation and compliance with vitamin D and Calcium fortified-milk in schoolchildren. The first phase was performed by a panel of 212 schoolchildren from both sexes using a 5- point hedonic questionnaire with both images and words. And, the second phase was carried out on 200 children using an 8-item questionnaire. In sensory evaluation 44.4% of the students described the taste of the fortified milk as bad, while in the compliance study 85% of children were satisfied with the taste of vitamin D and Calcium - fortified milk. Only less than half of the students agreed with the continuation of the fortification program. Calcium and vitamin D fortification, resulting in unpleasant changes in the taste of milk, can challenge fortified milk distribution program for children. Further study is needed to provide a formulation that would result in a higher compliance among schoolchildren

Effectiveness of ultrasound and ultraviolet irradiation on degradation of carbaryl from aqueous solutions

Carbaryl [1-naphthyl-N-methyl carbamate] is a chemical in the carbamate family used chiefly as an insecticide. It is a cholinesterase inhibitor and is toxic to humans and classified as a likely human carcinogen. In the present study, the degradation of the carbaryl pesticide was investigated in the laboratory synthetic samples of tap water, in the effect of sonolysis and photolysis processes. This study was conducted during 2006-7 in Chemistry and Biochemistry of Pesticides Laboratory in Tehran University of Medical Sciences [TUMS] in Iran. The carbaryl [80%] was used for preparing samples. First concentration of all samples were 4 mg/l. Sonochemical examinations in ultrasound reactor was done in two 35, 130 Hz, and 100 w, and three time. Photolysis examinations has done in the effect of 400 w lamp and moderate pressure and 6 time, then the amount of pesticide in the samples has been measured by the High Performance Thin Layer Chromatography [HPTLC] method. The highest degradation in photolysis process after 1 hour in the 35 KHz was 35%, and in the 130 KHz was 63%. Degradation of carbaryl at 130 KHz is higher than 35 KHz at the same time. Carbaryl elimination was increased by arise frequency and exposure time. After 8 min in photolysis, 100% omitting has been showed. Degradation of carbaryl in high frequency ultrasound wavelength was more than low frequency. Degradation of carbaryl in water, combination of high frequency ultrasound wave length and UV irradiation was considerably more effective than ultrasound or ultraviolet irradiation alone

Treatment of low-strength industrial wastewater using anaerobic baffled reactor

The performance of an anaerobic baffled reactor at the pilot scale, with a 100-L volume and six compartments, that is used to treat low-strength industrial wastewater [671.5 +/- 49.9 mg COD/L, 350.1 +/- 36.8 mg BOD[5]/L and 443.8 +/- 60.7 mg SO[4][-2]/L] was studied. The reactor was started with a hydraulic retention time [HRT] of 25 h at 35 °C, which was gradually reduced to 3.33 h. The best reactor performance was observed with an organic loading rate [OLR] and a sulfate loading rate [SLR] of 4.45 g COD/L.d and 3.32 g SO[4][-2]/L.d, which was obtained at a HRT of 4 h. The COD and SO4-2 removal efficiencies were 78.6% and 89.2%, respectively. Additionally, the majority of the COD and SO[4][-2] removal occurred in the first compartment, up to 51.2% and 69.1%, respectively. Moreover, the pH in the first compartment was also the lowest. Subsequently, when the temperature was reduced to 20 °C at a HRT of 4 h, the maximum removal efficiencies for COD and SO[4][-2] decreased to 59.4% and 66.1%, respectively. In this case, the highest COD and SO[4][-2] removal efficiencies were observed in the third and fourth compartments, respectively, and these compartments had lower pH values. This phenomenon indicates that decrease in temperature causes transference of the acidogenic phase toward subsequent reactor compartments. In addition, these findings further show the potential for sulfate removal of the acidogenic phase

High performance thin layer chromatography analysis of deltamethrin residue on the impregnated bed nets during a leishmaniasis control program in Iran

The control of leishmaniasis, a tropical neglected disease, has been concern of Iranian health authorities due to the increasing number of cases during the last two decades. The objective of this study was to determine deltamethrine residue on the impregnated bed nets using HPTLC technique in a leishmaniasis control program in Iran. During this experimental study, a total of 130 small pieces of polyester netting were sewn to top, upper, and lower sides of some bed nets and then were impregnated with deltamethrin .The treated bed nets were distributed in Isfahan and Mashhad areas in April 2003. The samples were cut randomly after impregnation intervals. Deltamethrin was extracted using acetone from samples and the extract was applied for spotting onto plates. The plates were developed with n-hexane: ethyl acetate, 90+10[v/v], as a mobile phase in a Camage chamber. The qualifying of residue was observed in UV cabinet with lambda =254 nm wavelength. Data were analyzed using SPSS version 11.5. and Stata Version 8. A three way ANOVA was used to compare the means of deltamethrin residue in each area, group and measuring time. The Kruskal-Wallis test was used to compare the means of residue for each of these factors with the control separately. The retardation factor of deltamethrin was calculated 0.50 +/- 0.02. The residues of deltamethrin persisted well on impregnated nets at least for 15 weeks after impregnation. No significant difference could be detected in the loss of residue of insecticide in comparison to measuring times and positions of sampling pieces on the bed nets in these areas. Based on the results of the present study the use of HPTLC technique is recommended instead of other chromatographic methods for analysis of insecticide residue on the impregnated bed nets

Effect of low-level laser irradiation on separator induced tooth movement

Long time course of orthodontic treatment is considered as one of the major problems causing a decrease in patients' compliance. This problem is related to the rate of tooth movement during treatment. One of the newest approved methods that affect the bone remodeling and tooth movement is the low-level laser irradiation. The aim of the present study was to evaluate the effect of low-level laser irradiation on tooth movement following the separator placement. This experimental clinical trial was carried out in dental clinics of Mashhad University during 2006-2007. A total of 30 orthodontic patients participated in this study. On the first day, the separators were placed between the 5[th], 6[th] and the 7[th] teeth. Later, the low-level laser irradiation was applied to one half of each jaw for 5 days while the other half was left as control. The sides of the laser irradiation were selected, randomly. On the 6[th] day, the impression was taken from both arches and the distance between the teeth were measured by a leaf-like gauge. The data were statistically analyzed using paired t-test. The mean amount of the tooth movement in laser irradiated side in maxilla was 0.55 +/- 0.19 mm and in the opposite side 0.50 +/- 0.21 mm, and the difference was found to be statistically significant [p=0.031]. This finding in mandible was 0.048 +/- 0.21 mm in laser irradiated side and 0.48 +/- 0.24 mm in the other side however, the difference was insignificant, statistically [p=0.86]. Comparatively, the measurement of both jaws in the laser-irradiated side was 0.52 +/- 0.20 mm while it was 0.49 +/- 0.22 mm in the opposite side with no significant difference between two groups. Our findings suggest that the low-level laser irradiation can accelerate the tooth movement in maxilla more than that in mandible, but the difference between the mean amount of the total tooth movement in laser irradiated side and the control side was statistically insignificant

Prevalence of stunting, underweight, wasting and overweight among Iranian under-five-year-old children [2000-2002]

A key target of the Millennium Development Goals [MDG] toward eliminating poverty and hunger is to reduce malnutrition among children less than 5 years. Over the past 20 years developing countries have experienced accelerated urbanization and an increase in the incidence of overweight and obesity as a consequence. Monitoring progress of countries toward the MDG requires reliable data on the growth status of children at the national level. The purpose of this study was to determine the prevalence of stunting, underweight, wasting, overweight and obesity among under-five-year-old children of the Iranian households included in the National Comprehensive Study on Household Food Consumption Patterns and Nutritional Status [2000-2002]. Data from 7158 households, with a total of 2562 under-five-year-old children, selected through random systematic sampling from 28 provinces, were included in the study. Trained nutritionists measured weight [with Seca digital balance, to the nearest 100gr] and height [using tape, to the nearest 0.1 cm] of all the household members during three consecutive days, using standard protocols. Age was documented in months, based on birth certificates. For children under two years, weight was based on the mean of two weighings, and recumbent length was measured. Undernutrition was defined as less than 2 standard deviations [2SD] of weight-for-age, height-for-age and weight-for-height z-scores, and overweight+obesity as higher than 2SD. The results were expressed based on weighted means of the total country, rural, and urban areas, and for both sexes. The total prevalence of stunting was 13.1% [CI 95%: 11/8%-14.4%] and of underweight 7.6% [CI 95%: 6.6%-8.6%]. Prevalences of stunting and underweight in rural areas were twice those in urban areas. There were statistically nonsignificant gender differences: the prevalences of stunting and underweight were, respectively, 14.2% and 7.3% among boys, and 11.8% and 8.0% among girls. Wasting and overweight were less prevalent the proportion of wasting was 4.5% and of overweight+obesity 5.2%; the prevalence of the latter was similar in rural and urban areas but it was higher among girls. Finally, the prevalence of wasting in urban areas was twice that in rural areas. According to the WHO classifications based on underweight, stunting and wasting rates, Iran is grouped with the countries having low prevalence rates. The high prevalence of overweight in children must be taken seriously, and it is absolutely esential to pay sufficient attention to both ends of the malnutrition spectrum. The findings of this study indicate that in order to achieve the millennium goals, improvements in living standards and the quality of diets is essential

new approach to contrast enhancement in MAGICA gel dosimeter image with MRI technique

Sensitivity and resolution are two main parameters that have to be measured in gel dosimetry. However, the resolution in gel is strongly dependant on gel composition. Selection of optimum method in dose response readout and proper values of parameters can result in noise reduction as well as improvement of contrast, and spatial resolution considerably. MAGICA polymer gel dosimeters were manufactured and irradiated to different doses using a 60Co therapy unit. Imaging was performed in a 0.5T MRI with 8 echoes in air and water as a hydrogenous environment. Imaging condition was kept constant, as much as possible, in both imaging modalities. Images obtained from these two procedures were compared quantitatively. R2- dose curves have three different sections, sensitivity obtained in these three sections were 1.039, 1.671, 1.260 Gy[-1]S[-1] and 1.032, 1.729, 1.37 Gy[-1]S[-1] for water and air respectively. Calibration errors were investigated and graphically were compared in two different methods. Imaging in water medium for doses lower than 17 Gy led to a small reduction in spatial resolution was exchanged to a considerable increase of contrast in R2 map. For doses higher than17 Gy, imaging in water or air was preferred depending on the importance of contrast or spatial resolution

Early detection of noise induced hearing loss by extended high frequency audiometery

Surrounding noise, especially in industrial environments, is one of the most common etiologic factors of sensory-neural hearing loss [SNHL], which is not curable, but preventable. By industrialization of communities, the prevalence of the disease and its unfavorable socioeconomic outcome is growing up. Since the preventable defect, early diagnosis has the utmost importance. In recent years, the role of extended high frequency audiometry [EHFA] as a sensitive diagnostic tool for noise induced hearing loss has received much attention. This study deals with the role of EHFA in early diagnosis of this disorder. This was a retrospective cohort study during 2003-4 in Isfahan, Iran. A total number of 30 male labors, aged 20-50 years working in a noisy industrial environment, were compared with an equal number of controls with normal conventional audiometry, and no risk factor for other causes of SNHL according to their history and otoscopic examination. All 60 individuals underwent both types of conventional and extended high-frequency audiometry. Data were analyzed with SPSS software using t-test, paired t-test and correlation tests of Pearson and Spearman. There was no difference between the right and left ears. The exposed subjects had significantly worse hearing than the non exposed group, at all tested frequencies [especially at 16 KHz]. The age effect was notable in both groups. The correlation between high frequency threshold and duration of noise-exposure was significant only at 16, 18 and 20 KHz. The higher mean frequency threshold of the cases was predictable; the normal findings of conventional audiometry, reveal that EHFA can be useful in early diagnosis of acoustic injuries

[Evaluation of induced stress in PDL of anterior maxillary teeth by applying intrusive forces distal to the maxillary canine]

One of the precise methods for evaluating periodontal responses to orthodontic forces is finite element method. The aim of this study was to evaluate induced stresses in PDL of anterior teeth by application of intrusive forces distal to the canine. Solid works software was used to translate bidimentional images of the maxillary teeth [central, lateral, canine] into tridimentional images. PDL and alveolar bone around teeth were simulated and anterior teeth were positioned in an ideal arch with appropriate tip and torque, and rectangular wire was stablished rigidly on labial surfaces of the teeth. Models were modified to "Finite element model" by means of MSC-NASTRAN. Intrusive forces [35 gr] were applied on anterior wire distal to the canine and induced stresses were analyzed by means of MSC-PATRAN. By delivery of intrusive forces between the lateral and canine teeth, the maximum stress was concentrated in PDL of canine [8.38 x 10[-3] N/mm2] and the minimum stress was in PDL of central [7.6 x 10[-6] N/mm2]. Application of intrusive forces on the distal of canine teeth lead to un homogenous stress distribution in anterior area due to intrusive and unintended labiodistal movement. Therefore distal of canine is not an appropriate point for intrusive forces application

[Stress analysis of anterior maxillary teeth by applying intrusive forces between lateral and canine]

One of the precise methods for evaluating periodontal responses to orthodontic forces is finite element method [FEM]. In the following study PDL of anterior maxillary teeth [central, lateral, canine] has been analysed by FEM after applying intrusive forces. The Aim of this study was to evaluate induced stresses in PDL of anterior teeth by application of intrusive forces between lateral incisore and canine. Solid works software was used to translate bidimentional images of the maxillary anterior teeth [central, lateral, canine] into three dimentional images. PDL and alveolar bone around these teeth were simulated and anterior teeth were positioned in an ideal arch with appropriate tip and torque, and rectangular wire was established rigidly on labial surfaces of the teeth. Models were modified to [Finite element model] by means of MSC-NASTRAN software. Intrusive forces [35 gr] were applied on the wire between lateral and canine and induced stresses was analyzed by means of MSC-PATRAN. By delivery of intrusive forces between lateral and canine, maximum stresses were found in PDL of lateral incisor [4.23×10[-3] N/mm[2]] and minimum stresses were observed in PDL of central incisor [2.02×10[-6] N/mm[2]]. By application of intrusive forces between latral incisor and canine, maximum stresses were focused at the apex of lateral incisor and minimum stresses were in appical third of central's root

investigation on stress distribution of the anterior maxillary teeth PDL during the application of intrusive forces in midline

Finite element method is one of the highly precise methods to evaluate periodontal responses to orthodontic forces. The goal of the present study was to investigate the PDL response of anterior maxillary teeth [central, lateral, canine] during the application of intrusive forces using FEM. Solid works software was used to translate bidimensional images of the mentioned maxillary teeth into tridimensional ones. Then, PDL and alveolar bone were simulated around teeth and anterior teeth were positioned in an ideal arch with appropriate tip and torque and rectangular wire was placed rigidly on labial surfaces of teeth. These models were then modified to "Finite element model" by MSC-NASTRAN software. Intrusive forces were applied mesially on the anterior wire and induced stresses were analyzed by MSC-PATRAN. The maximum stress was observed in the PDL of lateral incisors [2.53x10[-3] N/mm[2]] and the minimum stress was in the PDL of canines [9.07.x10[-5] N/mm[2]]. Applying the intrusive forces in midline maximum stresses were focused on the apical part of lateral incisor and the minimum stresses were in the apically third of canine