Application of INAA to determine major elements concentrations in head hair of street children of Isfahan city, Iran

The street children phenomena and the number of street children is an increasing social problem in Isfahan and other big and growing towns. Because of the number of street children and the way that they affect society in childhood and when they become old, it is important to study their health and have baseline data on theire health problems. Hair element analysis is an important tool in the nutritional and environmental pollutions and measuring pollutions and measuring elemental concentrations in recently-grown hair provides a good way of studing their health. This study aimed to assess major element concentrations in the hair of street children in Isfahan using instrumental neutron activation analysis method. Six major elements (Ca, Cl, K, Mg, Na and S) of 17 Iranian street children (Isfahan) were determined. Data analysis found different profiles of the concentrations of Ca, K, Mg and S in samples. These results were discussed with reference to show of nutritional and environmental effects

Binary Mixtures of SH- and CH3-Terminated Self-Assembled Monolayers to Control the Average Spacing Between Aligned Gold Nanoparticles

This paper presents a method to control the average spacing between organometallic chemical vapor deposition (OMCVD) grown gold nanoparticles (Au NPs) in a line. Focused ion beam patterned CH3-terminated self-assembled monolayers are refilled systematically with different mixtures of SH- and CH3-terminated silanes. The average spacing between OMCVD Au NPs is demonstrated systematically to decrease by increasing the v/v% ratio of the thiols in the binary silane mixtures with SH- and CH3-terminated groups

Distribution of trace elements in the marine sediments along the South China Sea, Malaysia.

In order to complete having data base of elemental assessment of the east coast of Peninsular Malaysia marine sediments along the South China Sea coasts, trace elements are analyzed and their distribution in marine sediments is undertaken. The present study is done parallel with pervious study on elemental assessment of heavy metals, rare earth elements and actinides in the marine sediments of the east coast of Peninsular Malaysia. Thirty surface sediment samples were collected in this area, including regions of Kelantan, Terengganu, Pahang, Rompin and Johor Baharu. Multielemental analysis was carried out by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectroscopy. In both cases methodology validation was performed by certified reference material analyses. For the surface elemental distributions the enrichment factor values, average I geo and mC d values indicate that the trace elements of the surface sediments are uncontaminated in all sampling stations that are consistent with previous studies results of heavy metals, rare earth elements and actinides

Optimized Seizure Detection Algorithm: A Fast Approach for Onset of Epileptic in EEG Signals Using GT Discriminant Analysis and K-NN Classifier

Background: Epilepsy is a severe disorder of the central nervous system that predisposes the person to recurrent seizures. Fifty million people worldwide suffer from epilepsy; after Alzheimer’s and stroke, it is the third widespread nervous disorder. Objective: In this paper, an algorithm to detect the onset of epileptic seizures based on the analysis of brain electrical signals (EEG) has been proposed. 844 hours of EEG were recorded form 23 pediatric patients consecutively with 163 occurrences of seizures. Signals had been collected from Children’s Hospital Boston with a sampling frequency of 256 Hz through 18 channels in order to assess epilepsy surgery. By selecting effective features from seizure and non-seizure signals of each individual and putting them into two categories, the proposed algorithm detects the onset of seizures quickly and with high sensitivity. Method: In this algorithm, L-sec epochs of signals are displayed in form of a thirdorder tensor in spatial, spectral and temporal spaces by applying wavelet transform. Then, after applying general tensor discriminant analysis (GTDA) on tensors and calculating mapping matrix, feature vectors are extracted. GTDA increases the sensitivity of the algorithm by storing data without deleting them. Finally, K-Nearest neighbors (KNN) is used to classify the selected features. Results: The results of simulating algorithm on algorithm standard dataset shows that the algorithm is capable of detecting 98 percent of seizures with an average delay of 4.7 seconds and the average error rate detection of three errors in 24 hours. Conclusion: Today, the lack of an automated system to detect or predict the seizure onset is strongly felt

Evaluation of 40K in fruit collected in Malaysia by the determination of total potassium using neutron activation analysis.

Potassium is an extremely important major to element to the human body. Potassium in made up of three isotopes with abundances of 39K at 93.1%, 40K at 0.0118% and 41K at 6.88%. It is also very well known that 40K is to measure the single 1460.8 keV photon from beta-decay. However, this procedure requires a significant amount of sample and typical counting periods of at least a day in well-shielded germanium counting system. Another approach is to determination total potassium via neutron activation analysis using the well know 41K (n,c) 42K(T1/2 = 12.8 h)reaction and then evaluate 40K using the usual activity equationA = kN. In our laboratory we have effectively used thermal and epithermal neutron flux for neutron activation analysis to determine potassium in fruits. Upward to 7–9 batches of samples, which each of batch is including 14 samples so can be analysed in 1 day using only gram quan-tities of material. In such way on can increase the output of determining 40K by at least on order of magnitude. Result of a detailed investigation optimization of the methodology, quality control and detection limits will be presented for reference material and various fruits samples

Evaluation of Bitter Vetch Lines Under Irrigated and Rainfed Conditions

In order to determine the most promising lines of bitter vetch regarding drought tolerance in rainfed areas, an experiment was conducted with 16 lines, under irrigated and rainfed conditions at Dryland Agriculture Research Institute, Maragheh. A randomized complete block design with three replications was used for each experiment. Analysis of variance for both rainfed and irrigated conditions showed that there were significant differences between lines for all studied traits. Combined analysis of variance indicated significant differences between two environments for all traits except plant height. Genotype × environment interaction was significant for all traits, except for plant height, pod number per plant and seed number per pod. Comparing means under irrigated and rainfed conditions showed that Sel 2518 had the lowest number of days to flowering and Sel 2515 and Sel 2516 had shorter period of grain filling. Local bitter vetch possessed the highest plant height, biomass, number of pods per plant and seed yield. Biomass, number of pods per plant and plant height had highest correlations with seed yield in both conditions. According to three drought tolerance indices (STI, GMO and MP), the local landrace was recognized as the most drought tolerant line with ability to produce highest yield in both rainfed and irrigated environments. This landrace was separated from other lines in the cluster analysis. In some cases, lines Sel 2644 and Sel 2647, originated from Bulgaria, were grouped with the local landrace. The results indicate that the local landrace was more productive than other lines under study and therefore, it is possible to identify suitable varieties for cultivation by evaluating different landraces of bitter vetc

Radiation shielding assessment for interventional radiology personnel: Geant4 dosimetry of lead-free compositions

The inherent biological hazards associated with ionizing radiation necessitate the implementation of effective shielding measures, particularly in medical applications. Interventional radiology, in particular, poses a unique challenge as it often exposes medical personnel to prolonged periods of high x-ray doses. Historically, lead and lead-based compounds have been the primary materials employed for shielding against photons. However, the drawbacks of lead, including its substantial weight causing personnel’s inflexibility and its toxicity, have raised concerns regarding its long-term impact on both human health and the environment. Barium tantalate has emerged as a promising alternative, due to its unique attenuation properties against low-energy x-rays, specifically targeting the weak absorption area of lead. In the present study, we employ the Geant4 Monte Carlo simulation tool to investigate various formulations of barium tantalate doped with rare earth elements. The aim is to identify the optimal composition for shielding x-rays in the context of interventional radiology. To achieve this, we employ a reference x-ray spectrum typical of interventional radiology procedures, with energies extending up to 90 keV, within a carefully designed simulation setup. Our primary performance indicator is the reduction in air kerma transmission. Furthermore, we assess the absorbed doses to critical organs at risk within a standard human body phantom protected by the shield. Our results demonstrate that specific concentrations of the examined rare earth impurities can enhance the shielding performance of barium tantalate. To mitigate x-ray exposure in interventional radiology, our analysis reveals that the most effective shielding performance is achieved when using barium tantalate compositions containing 15% Erbium or 10% Samarium by weight. These findings suggest the possibility of developing lead-free shielding solutions or apron for interventional radiology personnel, offering a remarkable reduction in weight (exceeding 30%)while maintaining shielding performance at levels comparable to traditional lead-based materials