Joints of composite construction in marine structures

Imperial Users onl

Microwave response of confined soliton pairs (Bipolarons) in (N-Methylphenazinium) x (Phenazine) 1-x (Tetracyanoquinodimethanide)

Journal ArticleThe temperature-dependent dielectric response and conductivity at =1010 Hz is reported for the title compound, (NMP)x(Phen)i-x(TCNQ), in the regime 0.50<-x<-0.59, spanning commensurate, bipolaron, and incommensurate regimes. The large and strongly temperature-dependent dielectric constant and o-(1010 HZ) are accounted for by a model based on the dynamics of pinned charge-density waves and the presence of relatively mobile charged bipolarons (confined soliton pairs) in the commensurate phase

Relation between clinical features and gastric emptying time in diabetic patients

BACKGROUND: Gastroparesis is characterized by delayed gastric emptying. This pathology is usually observed in patients with diabetes. One standard approach to quantitative assessment of gastric emptying is scintigraphic study. The aim of present study was to perform scintigraphic study of gastric emptying time in patient with diabetes and to find its correlation with patients' characteristics. MATERIALS AND METHODS: Gastric emptying was assessed in 19 patients with type 2 diabetes (mean age of 61.04 ± 6.09 years) and 6 healthy volunteers. Characteristics of the patients were sex, age, duration of diabetes, blood sugar and serum HbA1c level. RESULTS: Results of present study revealed that gastric emptying half time was significantly larger in patients with type 2 diabetes as compared with healthy volunteers (P-value < 0.05). While correlation of sex, age, duration of diabetes and blood sugar with gastric emptying time was not statistically significant, HbA1c level had significant effect on gastric emptying time. CONCLUSION: Results of this prospective study indicated that level of serum HbA1c is an effecting factor on gastric emptying time in patients with type 2 diabetes; however, these preliminary findings should be validated in larger and well-designed studies. Copyright © 2015 Via Medica

Comparison of three with six regions of interest analyses in patients with idiopathic constipation undertaking colon transit scintigraphy using 67Ga-citrate

OBJECTIVE AND INTRODUCTION: Preparation of data from 6 geometric regions of interest in the colon is time consuming, and can become impractical in the environment of busy Nuclear Medicine Departments. Therefore, we have investigated and demonstrated an alternative method for obtaining the same diagnostic information from an analysis of patients with idiopathic constipation who underwent colon transit scintigraphy using 67Ga-citrate. Data analysis methods using three regions of interest are compared to the results obtained using the more time consuming 6 regions of interest method to analyze the data. MATERIALS AND METHODS: In this study, we report our results of the comparative reanalysis of data obtained by more traditional methods. We compare 3 regions of interest (ROI) which were taken from areas including the right colon, left colon and the rectosigmoid colon, with original work using our alternative 6 (ROI) diagnostic methodology. In addition, the proximal colonic emptying (PCE) was determined at 24 hr post ingestion among members of 3 identified subject groups. RESULTS: The distribution of activity as the ingested 67Ga-citrate passes through the colon constitutes an activity profile. The mean activity position in the colon can be determined from subsequent radiographic images and from this the mean clearance time can be calculated. In quantitative assessment, this represents the time at which half of activity was eliminated from colon (mean half clearance time - MCT) which did not appear different in the reanalysis. There is no significant difference in the current study in GMC 24h, GMC 48h and GMC 72h between two groups using the Man Whitney u test (p &gt; 0.05), while in the previous work the results were statistically significant for the two later time periods GMC (GMC 48h and GMC 72h) (p = 0.016 and p = 0.027 respectively). The PCE in the group 1 was = 2.50 (0.37); group 2, 1.57 (0.47) and group 3, 2.97. The PCE was not different between the two groups (p = 0.21). CONCLUSIONS: This investigation demonstrated that the radionuclide colon transit study using 67Ga-citrate is a safe, physiologic, and quantitative method for evaluating the transit of fecal material from cecum to rectum. Although, the visual assessment of diagnosis of the subjects in the two analyses is the same, it was not completely supported by quantitative measurements. Therefore, further studies need to be done

The effect of an iodine restricted including no sea foods diet, on technetium-99m thyroid scintigraphy: A neglected issue in nuclear medicine practice

Although it is recommended to patients to avoid sea food and iodine-containing medications prior to iodine-131 ( 131I) scanning, the efficacy of this diet as for technetium-99m pertechnetate ( 99mTc-P) thyroid scintigraphy is not well addressed in the literature. We evaluated a self-managed, outpatients, iodine restricted diet (IRD) designed to reduce total body iodine in preparation for such a scan. We have studied 39 patients who referred to our Department for multinodular goiter, 30 females and 9 males, aged: 14-54 years and their 99mTc-P thyroid scintigraphy showed poor visualization of the thyroid gland. These patiens were living in regions with high consumption of sea foods went underwent a two-weeks iodine restriction including restriction of sea food diet for the reduction of iodine body content. These patients were called for a repeated scan after going on a IRD for at least two weeks. The two scans were compared visually, and by semiquantitative analysis. Semiquantitative analysis was applied in 8 regions of interest (ROI) by using Wilcoxon signed rank test. Thirty-six subjects had better quality scintigraphy images in the post IRD thyroid scan, as was visually assessed by two nuclear medicine physicians. Semiquantitatetively, there was a significant difference in the mean counts of ROI of the right and the left thyroid lobes in favor of the post IRD scans (P&lt;0.05). In conclusion, this study suggests that in patients with multinodular goiter, living in regions with high consumption of sea foods a two-weeks diet for the reduction of iodine body content induces in most of the cases a slightly better diagnostic thyroid 99mTc-P scan

Improving the Power Quality in Tehran Metro Line-Two Using the Ant Colony Algorithm

This research aims to survey the improvement of power quality in Tehran metro line 2 using the ant colony algorithm and to investigate all the factors affecting the achievement of this goal. In order to put Tehran on the road of sustainable development, finding a solution for dealing with air pollution is essential. The use of public transportation, especially metro, is one of the ways to achieve this goal. Since the highest share of pollutants in Tehran belongs to cars and mobile sources, relative statistical indicators are estimated through assuming the effect of metro lines development and subsequently reduction of traffic on power quality index