319 research outputs found

    An M-QAM Signal Modulation Recognition Algorithm in AWGN Channel

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    Computing the distinct features from input data, before the classification, is a part of complexity to the methods of Automatic Modulation Classification (AMC) which deals with modulation classification was a pattern recognition problem. Although the algorithms that focus on MultiLevel Quadrature Amplitude Modulation (M-QAM) which underneath different channel scenarios was well detailed. A search of the literature revealed indicates that few studies were done on the classification of high order M-QAM modulation schemes like128-QAM, 256-QAM, 512-QAM and1024-QAM. This work is focusing on the investigation of the powerful capability of the natural logarithmic properties and the possibility of extracting Higher-Order Cumulant's (HOC) features from input data received raw. The HOC signals were extracted under Additive White Gaussian Noise (AWGN) channel with four effective parameters which were defined to distinguished the types of modulation from the set; 4-QAM~1024-QAM. This approach makes the recognizer more intelligent and improves the success rate of classification. From simulation results, which was achieved under statistical models for noisy channels, manifest that recognized algorithm executes was recognizing in M-QAM, furthermore, most results were promising and showed that the logarithmic classifier works well over both AWGN and different fading channels, as well as it can achieve a reliable recognition rate even at a lower signal-to-noise ratio (less than zero), it can be considered as an Integrated Automatic Modulation Classification (AMC) system in order to identify high order of M-QAM signals that applied a unique logarithmic classifier, to represents higher versatility, hence it has a superior performance via all previous works in automatic modulation identification systemComment: 18 page

    Baseline aortic pre-ejection interval predicts reverse remodeling and clinical improvement after cardiac resynchronization therapy

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    Background: Cardiac resynchronization therapy (CRT) has been shown to reduce heart failure-related morbidity and mortality. However, approximately one in three patients do not respond to CRT. The aim of the current study was to determine the parameter(s) which predict reverse remodeling and clinical improvement after CRT. Methods: A total of 54 patients (43 male, 11 female; mean age 61.9 ± 10.5 years) with heart failure and New York Heart Association (NYHA) class III–IV symptoms and in whom left ventricular ejection fraction (LVEF) was £ 35% and QRS duration was ≥ 120 ms, despite optimal medical therapy, were enrolled. An echocardiographic examination was performed before, and six months after, CRT. An echocardiographic response was defined as a reduction of end-systolic volume ≥ 10% after six months, and a clinical response was defined as a reduction ≥ 1 in the NYHA functional class score. Results: An echocardiographic response was observed in 38 (70.4%) of the patients and a clinical response occurred in 41 (75.9%) of the patients. Of the dyssynchrony parameters, only the aortic pre-ejection interval (APEI) was observed to significantly predict the clinical response (p = 0.048) and echocardiographic response (p = 0.037). A 180.5 ms cut-off value for the APEI predicted the clinical response with a sensitivity of 92.3% and a specificity of 39%, and the echocardiographic response with a sensitivity of 93.0% and a specificity of 42%. Conclusions: APEI derived from pulsed-wave Doppler, which is available in every echocardiography machine, is a simple and practical method that could be used to select patients for CRT. (Cardiol J 2011; 18, 6: 639–647

    Total white blood cell count is associated with the presence, severity and extent of coronary atherosclerosis detected by dual-source multislice computed tomographic coronary angiography

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    Background: Total white blood cell (WBC) count has been consistently shown to be an independent risk factor and predictor for future cardiovascular outcomes, regardless of disease status in coronary artery disease (CAD). The purpose of this study is to evaluate the relationship between total WBC count and the presence, severity and extent of coronary atherosclerosis detected in subjects undergoing multislice computed tomographic (MSCT) coronary angiography for suspected CAD. Methods: A total of 817 patients were enrolled in this cross-sectional study. Non-significant coronary plaque was defined as lesions causing &#163; 50% luminal narrowing, and significant coronary plaque was defined as lesions causing > 50% luminal narrowing. For each segment, coronary atherosclerotic lesions were categorized as none, calcified, non-calcified and mixed. All images were interpreted immediately after scanning by an experienced radiologist. Results: An association between hypertension, diabetes mellitus, age, gender, hyperlipidemia, smoking, total WBC counts and coronary atherosclerosis was found when patients were grouped into two categories according to the presence of coronary atherosclerosis (p < 0.05). Although plaque morphology was not associated with total WBC counts, the extent of coronary atherosclerosis was increased with higher total WBC quartiles (p = 0.006). Patients with critical luminal stenosis had higher levels of total WBC counts when compared to patients with non-critical luminal narrowing (7,982 &#177; 2,287 vs 7,184 &#177; 1,944, p < 0.05). Conclusions: Our study demonstrated that total WBC counts play an important role in inflammation and are associated with the presence, severity and extent of coronary atherosclerosis detected by MSCT. Further studies are needed to assess the true impact of WBC counts on coronary atherosclerosis, and to promote its use in predicting CAD. (Cardiol J 2011; 18, 4: 371&#8211;377

    Development of an optimum proliferation medium via the graph kernel statistical analysis method for genetically stable in vitro propagation of endemic Thymus cilicicus (Turkey)

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    Thymus cilicicus is an endemic Eastern Mediterranean element that has aromatic-medicinal properties. Its natural population spreads across gravelly ground and open rocky areas of South and Southwest Anatolia. The current study on in vitro propagation of T. cilicicus focused deeply on environmental applications such as the development of an optimum medium composition for efficient and genetically stable micropropagation and improved preservation procedures for long-time conservation of elite germplasms for further studies. For this purpose, MS and OM media were used individually and in combination with cytokinins, charcoal, AgNO3, Fe-EDDHA, and H3BO3. The raw data were statistically analyzed via the graph kernel method to optimize the nonlinear relationship between all parameters. The optimal proliferation medium for T. cilicicus was OM supplemented with a combination of 10 g L-1 charcoal and 1 mg L-1 KIN and the calculated averages of the best regeneration rate, the best shoot number and the best shoot length were 96.89%, 3 and 1.24 respectively on this medium. The determination of genetic stability of in vitro grown plants on the optimum medium compositions obtained by the graph kernel method was carried out with the use of the ISSR-PCR technique. All the ISSR primers produced a total of 192 reproductive band profiles, none of which were polymorphic. Furthermore, the micropropagated plants were successfully rooted and acclimatized to greenhouse conditions. In this study, we present a graph kernel multiple propagation index which considers all the possible parameters needing to be analyzed. Such an index is used for the first time for the determination of the optimum proliferation medium

    Structure of the Current Sheet in the 11 July 2017 Electron Diffusion Region Event.

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    The structure of the current sheet along the Magnetospheric Multiscale (MMS) orbit is examined during the 11 July 2017 Electron Diffusion Region (EDR) event. The location of MMS relative to the X-line is deduced and used to obtain the spatial changes in the electron parameters. The electron velocity gradient values are used to estimate the reconnection electric field sustained by nongyrotropic pressure. It is shown that the observations are consistent with theoretical expectations for an inner EDR in 2-D reconnection. That is, the magnetic field gradient scale, where the electric field due to electron nongyrotropic pressure dominates, is comparable to the gyroscale of the thermal electrons at the edge of the inner EDR. Our approximation of the MMS observations using a steady state, quasi-2-D, tailward retreating X-line was valid only for about 1.4 s. This suggests that the inner EDR is localized; that is, electron outflow jet braking takes place within an ion inertia scale from the X-line. The existence of multiple events or current sheet processes outside the EDR may play an important role in the geometry of reconnection in the near-Earth magnetotail

    Near-Earth plasma sheet boundary dynamics during substorm dipolarization.

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    We report on the large-scale evolution of dipolarization in the near-Earth plasma sheet during an intense (AL ~ -1000 nT) substorm on August 10, 2016, when multiple spacecraft at radial distances between 4 and 15 R E were present in the night-side magnetosphere. This global dipolarization consisted of multiple short-timescale (a couple of minutes) B z disturbances detected by spacecraft distributed over 9 MLT, consistent with the large-scale substorm current wedge observed by ground-based magnetometers. The four spacecraft of the Magnetospheric Multiscale were located in the southern hemisphere plasma sheet and observed fast flow disturbances associated with this dipolarization. The high-time-resolution measurements from MMS enable us to detect the rapid motion of the field structures and flow disturbances separately. A distinct pattern of the flow and field disturbance near the plasma boundaries was found. We suggest that a vortex motion created around the localized flows resulted in another field-aligned current system at the off-equatorial side of the BBF-associated R1/R2 systems, as was predicted by the MHD simulation of a localized reconnection jet. The observations by GOES and Geotail, which were located in the opposite hemisphere and local time, support this view. We demonstrate that the processes of both Earthward flow braking and of accumulated magnetic flux evolving tailward also control the dynamics in the boundary region of the near-Earth plasma sheet.Graphical AbstractMultispacecraft observations of dipolarization (left panel). Magnetic field component normal to the current sheet (BZ) observed in the night side magnetosphere are plotted from post-midnight to premidnight region: a GOES 13, b Van Allen Probe-A, c GOES 14, d GOES 15, e MMS3, g Geotail, h Cluster 1, together with f a combined product of energy spectra of electrons from MMS1 and MMS3 and i auroral electrojet indices. Spacecraft location in the GSM X-Y plane (upper right panel). Colorcoded By disturbances around the reconnection jets from the MHD simulation of the reconnection by Birn and Hesse (1996) (lower right panel). MMS and GOES 14-15 observed disturbances similar to those at the location indicated by arrows

    Proanthocyanidin to prevent formation of the reexpansion pulmonary edema

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    <p>Abstract</p> <p>Background</p> <p>We aimed to investigate the preventive effect of Proanthocyanidine (PC) in the prevention of RPE formation.</p> <p>Methods</p> <p>Subjects were divided into four groups each containing 10 rats. In the Control Group (CG): RPE wasn't performed. Then subjects were followed up for three days and they were sacrificed after the follow up period. Samplings were made from tissues for measurement of biochemical and histopathologic parameters. In the Second Group (PCG): The same protocol as CG was applied, except the administration of PC to the subjects. In the third RPE Group (RPEG): Again the same protocol as CG was applied, but as a difference, RPE was performed. In the Treatment Group (TG): The same protocol as RPEG was applied except the administration of PC to the subjects.</p> <p>Results</p> <p>In RPEG group, the most important histopathological finding was severe pulmonary edema with alveolar damage and acute inflammatory cells. These findings were less in the TG group. RPE caused increased MDA levels, and decreased GPx, SOD and CAT activity significantly in lung tissue.</p> <p>Conclusion</p> <p>PC decreased MDA levels. Oxidative stress plays an important role in pathophysiology of RPE and PC treatment was shown to be useful to prevent formation of RPE.</p

    Gastroenterology Cases of Cutaneous Leukocytoclastic Vasculitis

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    Rarely, leukocytoclastic vasculitis can result from ischemic colitis, inflammatory bowel disease, and cryoglobulinemia. There is no established standard for the treatment of leukocytoclastic vasculitis associated with gastroenterologic diseases. This paper presents three cases of leukoytoclastic vasculitis, each of which is associated with a different gastroenterologic condition: ischemic colitis, Crohn’s disease, and chronic hepatitis C. Each condition went into remission by treatment of leukocytoclastic vasculitis, regardless of the underlying disease

    Athletic performance, sports experience, and exercise addiction: an association study on ANKK1 gene polymorphism rs1800497

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    IntroductionExercise addiction is a phenomenon being able to affecting the athletic performance. The gene, ANKK1 and the polymorphism NM_178510.2:c.2137G &gt; A (rs1800497) has been linked to the exercise addiction. However, further studies on diverse populations and sport branches are needed to totally explore the possible association of this polymorphism with the athletic performance. Thus, the present study aims to decipher any possible relations of the rs1800497 polymorphism with the athletic performance/personal best (PB) and sport experience of elite athletes.MethodsSixty volunteer elite athletes (31 sprint/power and 29 endurance) and 20 control/sedentary participated in the study. The polymorphism was genotyped using whole exome sequencing approach and PB were determined according to the International Association of Athletics Federations (IAAF) score.ResultsOur results underlined that there were not any significance differences for both allele and genotype frequencies between the groups in terms of athletic performance, although the frequency of allele G was higher (p &gt; 0.05). Nevertheless, sport experience significantly associated with the rs1800496 polymorphism (p &lt; 0.05).DiscussionIn conclusion, genotype G/G could be inferred to be linked to the higher sport experience and athletic performance. Still, further studies with higher number of participants are needed to conclude the association of this polymorphism with athletic parameters
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