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581.
Corsini J Shoker L Sanei S Alarcón G 《IEEE transactions on bio-medical engineering》2006,53(5):790-799
Most of the methods for prediction of epilepsy recently reported in the literature are based on the evaluation of chaotic behavior of intracranial electroencephalographic (EEG) recordings. These recordings require intensive surgical operations to implant the electrodes within the brain which are hazardous to the patient. Here, we have developed a novel approach to quantify the dynamical changes of the brain using the scalp EEG. The scalp signals are preprocessed by means of an effective block-based blind source separation (BSS) technique to separate the underlying sources within the brain. The algorithm significantly removes the effect of eye blinking artifacts. An overlap window procedure has been incorporated in order to mitigate the inherent permutation problem of BSS and maintain the continuity of the estimated sources. Chaotic behavior of the underlying sources has then been evaluated by measuring the largest Lyapunov exponent. For our experiments, we provided twenty sets of simultaneous intracranial and scalp EEG recordings from twenty patients. The above recordings have been compared. Similar results were obtained when the intracranial electrodes recorded the electrical activity of the epileptic focus. Our preliminary results show a great improvement when the epileptic focus is not captured by the intracranial electrodes. 相似文献
582.
Took CC Sanei S Chambers J Dunne S 《IEEE transactions on bio-medical engineering》2006,53(10):2123-2126
The underdetermined blind source separation problem using a filtering approach is addressed. An extension of the FastICA algorithm is devised which exploits the disparity in the kurtoses of the underlying sources to estimate the mixing matrix and thereafter achieves source recovery by employing the ll-norm algorithm. Besides, we demonstrate how promising FastICA can be to extract the sources. Furthermore, we illustrate how this scenario is particularly appropriate for the separation of temporomandibular joint (TMJ) sounds. 相似文献
583.
近年来,伊朗许多旧城区的建筑都变得破旧不堪,探索针对旧城区的改造方法对建筑师、规划师和当局政府来说都是一项巨大的挑战。该文通过对伊朗旧城区建筑改造的3种方法的比较分析,认为伊朗传统建筑不仅包括建筑的审美和结构性因素,还体现了对环境和文化因素的极大尊重,如果能够充分重视传统建筑中的这些特点,并将它们有意识地应用到新建筑设计与旧建筑立面改造中,将有助于建筑师设计出与环境、文化和谐共生的建筑。 相似文献
584.
Saeid Mohamadi Zahedi 《塑料、橡胶和复合材料》2018,47(6):273-281
Silver nanoparticles (AgNPs) are widely used in various fields but their physical and chemical instability have limited their applications. The present work demonstrates a novel approach for the synthesis and stabilising of AgNPs. Chitosan and carboxymethyl β-cyclodextrin were used to prepare a polymeric hydrogel with glutaraldehyde as cross-linker. As a result, AgNPs were formed with very high dispersion and stability in the hydrogel structure. It is possible to create nanoreactors to produce AgNPs by adding CM-βCD to the structure of the hydrogel. Fourier transform infrared (FTIR) analysis was employed to characterise the Cs-CM-βCD hydrogel. The morphologies of pure Cs-CM-βCD hydrogel and silver nanocomposite were observed by scanning electron microscopy. Moreover, UV–VIS spectroscopy and X-ray diffraction were used to characterise the prepared silver nanocomposite. In addition, the antibacterial properties of these silver nanocomposite hydrogels were investigated against Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). 相似文献
585.
Ansari-Lari M Hosseinzadeh S Shekarforoush SS Abdollahi M Berizi E 《International journal of food microbiology》2011,144(3):475-479
Campylobacter species are among the most common bacterial causes of human gastroenteritis in many countries, and poultry meat is considered as a major source of human campylobacteriosis. The present study was conducted to determine the prevalence of infection by Campylobacter jejuni and Campylobacter coli in broiler flocks in Shiraz and to investigate the possible risk factors for the campylobacter infections in this area. For detection of campylobacter, multiplex polymerase chain reaction (mPCR) was used. Between August and September 2009, a total of 100 broiler flocks from 100 commercial broiler farms were selected at slaughter and campylobacter status was determined by mPCR on caecal samples. Data about farms and flocks were collected by questionnaires. Approximately 76% (95% CI: 67-84%) of the flocks were positive for C. jejuni or C. coli. Twenty two percent were positive for C. jejuni, 32% for C. coli and 22% for both species. Results of the statistical analysis using multivariable logistic regression showed that the odds of flock infection decreased when level of owner's education (years) increased (OR = 0.86, P = 0.04), also odds of infection was nearly five times higher when age at slaughter was ≥ 45 days compared with < 45 days (OR = 5.3, P = 0.003) and use of antibiotic medications at early stage of production period was negatively associated with the infection status of the flock (OR = 0.33, OR = 0.059). We found no evidence of the effects of any other factors such as time interval between successive flocks, hygiene measures and number of broiler houses on the farm on the prevalence of campylobacter infection. Getting more attention to the health education issues and planning qualitative studies to reveal the behavioral aspects of the management policy, may be subjects of interest for future researches. 相似文献
586.
Ali Mohammadi Shahin Rafiee Seyed Saeid Mohtasebi Hamed Rafiee 《Renewable Energy》2010,35(5):1071-1075
This study examines energy consumption of inputs and output used in kiwifruit production, and to find relationship between energy inputs and yield in Mazandaran, Iran. For this purpose, the data were collected from 86 kiwifruit orchards which were selected based on random sampling method. The results indicated that total energy inputs were 30285.62 MJ ha?1. About 47% of this was generated by total fertilizer including farmyard manure, 28% from diesel fuel and machinery. About 70% of the total energy inputs used in kiwifruit production was indirect while only about 30% was direct. Econometric estimation results revealed that energy inputs of human labour, water for irrigation, total fertilizer and machinery contributed significantly to the yield. The impact of human labour energy (0.17) was found the highest among the other inputs in kiwifruit production. The results also showed that direct, indirect and renewable and non-renewable, energy forms had a positive impact on output level. Cost analysis showed that total cost of kiwifruit production was obtained as 6063.81 $ ha?1. The productivity (4.05 kg $?1) was obtained by dividing kiwifruit yield by total production cost. 相似文献
587.
Abrari Saeid Daneshvari-Esfahlan Vahid Hosseini Mir Ghasem Mahmoodi Raana Hacker Viktor 《Journal of Applied Electrochemistry》2022,52(4):755-764
Journal of Applied Electrochemistry - In the present work, Ni@Pd core–shell nanoparticles are successfully deposited on multi-walled carbon nanotubes as support and investigated their... 相似文献
588.
Soleiman Hosseinpour Shahin RafieeSeyed Saeid Mohtasebi Mortaza Aghbashlo 《Journal of food engineering》2013
The effects of drying temperature and drying medium velocity on color change kinetics of shrimp viz. lightness (L∗), redness (a∗), yellowness (b∗), total color difference (ΔE), chroma (CH), hue angle (H°), and browning index (BI) were on-lineally investigated. Drying experiments were carried out on dryer equipped with computer vision systems using hot air drying (HAD) temperatures of 50–90 °C and superheated steam drying (SSD) temperatures of 110–120 °C at drying medium velocities of 1–2 m/s. Zero-, first-order, and fractional conversion models were utilized to describe the color changes of shrimps and the fractional conversion model successfully tracked the experimental data. The results showed that the color parameters were significantly influenced by the studied parameters. Lightness of the samples decreased, while other color parameters increased as drying proceeded. Generally, increasing drying medium temperature decreased L∗ and H°, whereas increased other color parameters. The color characteristic of the SSD finished products were acceptable than the HAD processed samples. Finally, dimensionless moisture content of shrimps during drying was accurately correlated to the color parameters and drying time using a quadratic regression model. Moisture ratio had strong relationship with the lightness change compared with the redness and yellowness variations. 相似文献