264 research outputs found

    Detection of Focal Epileptic Seizure Using NIRS Signal Based on Discrete Wavelet Transform

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    Background: Despite the large number of research and significant advances in neuroscience, the hemodynamic activities of epilepsy have been rarely investigated due to high costs, need for contrast agents in fMRI and PET, lack of signals during epileptic seizure and un-portability of the equipment. Recently, Near-infrared spectroscopy (NIRS) system has attracted a large number of researchers. This system does not have the above-mentioned problems and provides a better temporal resolution than the other equipment; however, it cannot be compared to PET or fMRI, in terms of spatial resolution. The project was conducted with a feasibility study to detect epileptic seizures and extraction of epileptic dynamics using a time multiplex system at 2 wavelengths of 740 and 850 nm. Analyzing the frequency and temporal-domains of 8 patients with focal epilepsy in temporal area during the time of sleeping, we can identify the most difference between epileptic and normal conditions in low-frequencies at the high order Daubechies wavelet transform of hemodynamic components. The main challenge is the significant resemblances between epileptic dynamic and motion artifact in low frequencies. Finally, using the most appropriate features such as Shannon entropy and the new index that we named “upgraded cumulants” showing proper separability under t test and also by using different classifiers, the best result was achieved with the help of SVM classifier with an accuracy of 78.57%

    Numerical Parametric Study of Wind-Driven Rain and Overhang Effectiveness on a Mid-Rise Building

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    The question of how wind and wind-accompanied rain are properly predicted, regardless of the method, whether experimental, semi-empirical or numerical is to this day unsettled. Moreover, parametric study of the Wind-Driven Rain (WDR), and consequently its wetting building façades is rather insufficiently dealt with. Due to the destructive repercussions of moisture penetration induced by WDR, façade protection in form of an overhang, which is considered as the most effective means to address the issue with, in regions with high levels of liquid precipitation, is the necessity of this study. Suitable numerical solution, alongside delving into the effect of numerous parameters governing the natural phenomenon, including wind direction and speed, rainfall intensity, and overhang size and shape, is the target of this work. To reach this goal, a MATLAB code controls raindrop injection into pre-solved domain of external flow on stand-alone and surrounded building. Wind flow solution of multiple turbulence schemes is bestowed upon ANSYS Fluent software package. Drag simulation and inlet velocity profiles, are hooked to the solver using User-Defined Functions (UDFs). Validation of wind simulation is done by comparing the predictions to wind-tunnel measurements. Validation of rain simulation on the other hand is performed by comparing the results to real-life conditions on a medium-rise building. Results of validation are rather promising for the upper-half of the windward façade. Proper technique of simulation of wind with conventional two-equation turbulence models, alongside the inlet velocity profiles is found to be boundary-treated Standard k-, wind log-law. Overhang presence and its shape and size are vastly studied and parametrized to find the effect of those parameters on the effectiveness of the overhang. This study shows that although rainfall intensity is faintly influential, the wind speed and direction, alongside overhang size and shape, considerably influence catch ratio and effectiveness of the overhang. The effectiveness decreases by an increase in wind speed and increases for oblique winds. Façade effectiveness of the overhang decreases with an increase in rainfall intensity; although this parameter’s influence on point effectiveness is dependent upon the location of point on the façade. Finally, the wider the overhang, the more effective it is in protecting the façade, as a whole, from rain

    Online Epileptic Seizure Prediction Using Phase Synchronization and Two Time Characteristics: SOP and SPH

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    Background: The successful prediction of epileptic seizures will significantly improve the living conditions of patients with refractory epilepsy. A proper warning impending seizure system should be resulted not only in high accuracy and low false-positive alarms but also in suitable prediction time.Methods: In this research, the mean phase coherence index used as a reliable indicator for identifying the preictal period of the 14-patient Freiburg EEG dataset. In order to predict the seizures on-line, an adaptive Neuro-fuzzy model named ENFM (evolving neuro-fuzzy model) was used to classify the extracted features. The ENFM trained by a new class labeling method based on the temporal properties of a prediction characterized by two time intervals, seizure prediction horizon (SPH), and seizure occurrence period (SOP), which subsequently applied in the evaluation method. It is evident that an increase in the duration of the SPH can be more useful for the subject in preventing the irreparable consequences of the seizure, and provides adequate time to deal with the seizure. Also, a reduction in duration of the SOP can reduce the patient’s stress in the SOP interval. In this study, the optimal SOP and SPH obtained for each patient using Mamdani fuzzy inference system considering sensitivity, false-positive rate (FPR), and the two mentioned points, which generally ignored in most studies.Results: The results showed that last seizure, as well as 14-hour interictal period of each patient, were predicted on-line without false negative alarms: the average yielding of sensitivity by 100%, the average FPR by 0.13 per hour and the average prediction time by 30 minutes.Conclusion: Based on the obtained results, such a data-labeling method for ENFM showed promising seizure prediction for online machine learning using epileptic seizure data. Apart from that, the proposed fuzzy system can consider as an evaluation method for comparing the results of studies

    Linear Maps Preserving Invertibility or Spectral Radius on Some CC^{*}-algebras

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    Let AA be a unital CC^{*}-algebra which has a faithful state. If varphi:ArightarrowAvarphi:Arightarrow A is a unital linear map which is bijective and invertibility preserving or surjective and spectral radius preserving, then varphivarphi is a Jordan isomorphism. Also, we discuss other types of linear preserver maps on AA

    Electrochemical detection of carbidopa using a ferrocene-modified carbon nanotube paste electrode

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    A chemically modified carbon paste electrode (MCPE) containing ferrocene (FC) and carbon nanotubes (CNT) was constructed. The electrochemical behavior and stability of the MCPE were investigated by cyclic voltammetry. The electrocatalytic activity of the MCPE was investigated and it showed good characteristics for the oxidation of carbidopa (CD) in phosphate buffer solution (PBS). A linear concentration range of 5 to 600 μM CD, with a detection limit of 3.6±0.17 μM CD, was obtained. The diffusion coefficient of CD and the transfer coefficient () were also determined. The MCPE showed good reproducibility, remarkable long-term stability and especially good surface renewability by simple mechanical polishing. The results showed that this electrode could be used as an electrochemical sensor for the determination of CD in real samples, such as urine samples

    A sensitive simultaneous determination of epinephrine and tyrosine using an iron(III) doped zeolite-modified carbon paste electrode

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    A Zeolite modified carbon paste electrode doped with iron(III) was used as a highly sensitive and selective electrochemical sensor for simultaneous determination of minor amounts of epinephrine (Ep) and tyrosine (Tyr) as the biologically important compounds. The results of differential pulse voltammetry (DPV) using this modified electrode show two well-resolved anodic waves for the oxidation of Ep and Tyr ,which makes it possible for simultaneous determination of both compounds. A linear range from 0.9 to 216 mmol L-1 for Ep at a constant concentration of 30 mmol L-1 Tyr in buffered solution (phosphate buffer, pH 3.0) was obtained from DPV measurement using this electrode with a correlation coefficient of 0.9998 and a detection limit of 0.44 mmol L-1. The linear range, which is obtained for Tyr in the presence of 30 mmol L-1 Ep, was in the range from 1.2 to 90 µmol L-1 with a correlation coefficient of 0.9989 and a detection limit of 0.32 mmol L-1. The modified electrode had good reproducibility (RSD < 2.5%), low detection limit (sub-micromolar) and high sensitivity for the detection of both Ep and Tyr with a very high stability in its voltammetric response. The analytical performance of this sensor has been evaluated for detection of Ep and Tyr in human serum and in a pharmaceutical sample with satisfactory results

    Adrenal Hemorrhage in the Deceased Neonate Referred to Tehran Legal Medicine Organization

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    Adrenal hemorrhage during neonatal phase is more prevalent than was thought before and most of the cases are diagnosed after the autopsy. However massive hemorrhage is rare. The mozst important cause of adrenal hemorrhage is perinatal injuries, but large fetal size, maternal diabetes, congenital syphilis, anoxia, hemorrhagic diseases and immaturity are predisposing factors. Incidence rate of adrenal hemorrhage is 0.2% to 0.5% during perinatal phase. The diagnosis of the adrenal hemorrhage in this phase is rare. Our case was a four-day-old full term neonate who was born via normal vaginal delivery, with Apgar score 3. The baby was intubated immediately which was followed by seizure attacks and unfortunately death on the fourth day of life. The neonate was female with 3100 g weight. At autopsy the left kidney appeared larger than normal and the adrenal subcapsular hematoma which amounts to about 50 mL, was seen. According to previous studies delivery per vaginam, macrosomia and acidemia are some important risk factors for adrenal hemorrhage. Risk factors of the present case were normal vaginal delivery and acidemia. The neonate may present no symptom or sign during fetal or neonatal phase. So serial sonography is considered one of diagnostic methods

    A triclinic polymorph of (E)-2-(1-hy­droxy-3-phenyl­prop-2-en-1-yl­idene)-4,5-dimeth­oxy­cyclo­pent-4-ene-1,3-dione

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    The title compound, C16H14O5, is a triclinic polymorph of a previously reported monoclinic structure [Hosseinzadeh et al. (2011 ▶). Acta Cryst. E67, o1544]. The mol­ecule is roughly planar, the r.m.s. deviation from the least-squares plane of all non-H atoms being 0.092 Å. In the crystal, adjacent mol­ecules are linked through C—H⋯O hydrogen bonds into an infinite two-dimensional network parallel to (011). The layers are further connected via C—H⋯π inter­actions, forming a three-dimensional structure. Intra­molecular O—H⋯O and C—H⋯O hydrogen bonds are also observed

    Physical Inactivity Is Correlated with Levels of Quantitative C-reactive Protein in Serum, Independent of Obesity: Results of the National Surveillance of Risk Factors of Non-communicable Diseases in Iran

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    Increased C-reactive protein (CRP) levels are associated with coronary heart disease, stroke, and mortality. Physical activity prevents cardiovascular disorders, which can be partly mediated through reducing inflammation, including serum CRP levels. The association of different intensities of physical activity, sedentary behaviours, and C-reactive protein (CRP) levels in serum was examined after adjustment for markers of adiposity, including waist-circumference and body mass index (BMI), in a large population-based study. Using data of the SuRFNCD-2007 study, a large national representative population-based study in Iran, the relationship between quantitative CRP concentrations in serum and physical activity was examined in a sample of 3,001 Iranian adults. The global physical activity questionnaire (GPAQ) was used for evaluating the duration and intensity of physical activity. Total physical activity (TPA) was calculated using metabolic equivalents for the intensity of physical activity. Quantitative CRP concentrations in serum were measured with high-sensitivity enzyme immunoassay. The CRP levels in serum significantly correlated with TPA (r=-0.103, p=0.021 in men and r=-0.114, p=0.017 in women), duration of vigorous-intensity activity (r=-0.122, p=0.019 in men and r=-0.109, p=0.026 in women), duration of moderate-intensity activity (r=-0.107, p=0.031 in men and r=-0.118, p=0.020 in women), and duration of sedentary behaviours (r=0.092, p=0.029 in men and r=0.101, p=0.022 in women) after multiple adjustments for age, area of residence, BMI, waist-circumference, smoking, and diabetes mellitus. Physical activity (of both moderate and vigorous intensity) is inversely associated with the quantitative CRP levels in serum, independent of diabetes and body adiposity

    2-(3,4-Dimeth­oxy­phen­yl)-1H-benzimidazole

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    In title compound, C15H14N2O2, the dihedral angle between the 3,4-dimeth­oxy­phenyl group and the benzimidazole system is 26.47 (6)°. In the crystal, neighbouring mol­ecules are linked by N—H⋯N hydrogen bonds into C(4) chains propagating along the c-axis direction. The crystal structure also features weak C—H⋯O inter­actions
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