136 research outputs found
Prediction of recurrent ventricular arrhythmias after myocardial infarction by speckle tracking echocardiography
No full textBackground. Sudden cardiac death (SCD) due to ventricular arrhythmias in coronary heart disease frequently occurs when ejection fraction (EF) is 35%. There is a need for new predictors of SCD by imaging technologies to prospectively identify high-risk patients currently missed by EF criteria. A myocardial strain reduction by echocardiography can potentially be a direct indicator of non-viable myocardium, and SCD risk. We aimed to compare strain data of patients with structural heart disease with and without ventricular tachycardia (VT) regardless of EF.
Methods. We studied 72 patients (age, 61±13 years) with previous myocardial infarction scheduled for cardioverter-defibrillator (ICD) implantation. Thirty-six pts had documented VT and 36 pts presented with no VT. Left ventricular function and volumes and score index were determined by two-dimensional echocardiography. Radial and circumferential strain were measured by speckle tracking echocardiography and EchoPAC software (GE). Global strain was obtained by averaging the maximum systolic shortening in a 16-segment model.
Results. EF and LV volumes were equal in both groups, and those with recurrent ventricular arrhythmias and those without could not be differentiated. Multivariate analysis revealed that global (p=0.016) and posterior wall circumferential strain (p=0.007) were strong and independent predictors of the occurrence of arrhythmic events. Analysis of ROC curves showed that the optimal cutoff value for posterior wall circumferential strain was -6.2% for a sensitivity of 67% and a specificity of 89% in predicting arrhythmic events.
Conclusions. In patients with previous myocardial infarction circumferential strain is the strongest predictor of spontaneous ventricular arrhythmia with subsequent ICD therapy (as surrogate of sudden cardiac death) among other clinical and echocardiographic variables, that is, score index and left ventricular function and volumes
Corrigendum to “Promising electrochemical study of titanate based anodes in direct carbon fuel cell using walnut and almond shells biochar fuel” [J. Power Sources 434 (2019) 126679](S0378775319306500)(10.1016/j.jpowsour.2019.05.085)
No full text© 2019 Elsevier B.V. The authors regret that the family name of author Asia Rafique was wrongly added as ‘Asia Iftikhar’ in the original article, the corrected name is “Asia Rafique”. The authors would like to apologise for any inconvenience caused
Global and regional left ventricular strain indices in post-myocardial infarction patients with ventricular arrhythmias and moderately abnormal ejection fraction
No full textWe aimed to compare myocardial strains in ischemic heart patients with and without sustained ventricular tachycardia (VT) and moderately abnormal LVEF in order to investigate which index could better predict VT on the basis of the analysis of global and regional LV dysfunction. We studied 467 patients with previous myocardial infarction and LVEF > 35%. Fifty-one patients had documented VT and 416 patients presented with no VT. LV volumes and score index were obtained by two-dimensional echocardiography. Longitudinal, radial and circumferential strain were determined. Strains of infarct, border and remote zones were also obtained. There were no differences in standard LV two-dimensional parameters between patients with or without VT. ROC values were -12.7% for global longitudinal strain (AUC 0.72), -4.8% for posterior-inferior wall circumferential strain (AUC 0.80), 61ms for left ventricular mechanical dispersion (AUC 0.84), -10.1% for longitudinal strain of border zone (AUC 0.86), and -9.2% for circumferential strain of border zone (AUC 0.89). In patients with previous myocardial infarction and moderately abnormal LVEF, peri-infarct circumferential strain was the strongest predictor of documented ventricular arrhythmias among all strain quantitative indices. Additionally, strain values from posterior-inferior wall infarctions had a higher association with arrhythmic events compared to global strain
From nano-dendrite to nano-sphere of Co100-xNix alloy: Composition dependent morphology, structure and magnetic properties
No full textCo100-xNix (x = 0, 10, 20, 30, ..., 100) alloy nanostructures with controlled composition are prepared by hydrothermal method. The effects of composition on crystal structure, morphology, growth of nanostructure, and magnetic properties are described. The crystal structure is hexagonal closed pack (hcp) at x = 0, mixture of hcp and face-centered cubic (fcc) for 10 <= x <= 30, and purely fcc for x >= 40. The morphology is changed from nano-dendrite (x = 0) to flower like structure composed on spherical core and nanorods (x = 50) to nanosphere (x = 100). The isotropic (spherical shape) character increases with Ni Content. Compositional analyses show the controlled composition in nanostructure. The saturation magnetization is 156 emu/g at x = 0 and decreases linearly with alloy composition (x) to 55 emu/g at x = 100. The coercivity is 285 Oe at x = 0 (dendrite) and decrease gradually to 21 Oe at x = 80, and then increases to 146 Oe at x = 100. The effective anisotropy (K-eff) constant decreases gradually with alloy-composition and shows decaying exponential dependence on alloy-composition (x). Magnetic and structural properties are explained by combined consequences of composition and nanoscale effects. This study reveals that the composition of alloy plays important role in growth, morphology, crystal structure and hence, properties of nanostructure. (C) 2015 Elsevier B.V. All rights reserved.Natural Science Foundation of China [51371105, 51071023]SCI(E)[email protected]
Online Classified Advertisements & Consumer Buying Behavior: A Case of Analyzing the Behavior of Karachi Buyers towards "OLX
No full textt—The aim of this case study is to evaluate the impact of classified online ads available to shoppers for their convenience and to examine their buying behavior in Karachi. In this study sample size of 270 respondents has been taken by using convenient sampling technique. Internet is a feasible option of buying products so, the variables used in this study as an independent variables are usability, interactivity, trust, marketing mix, aesthetics and dependent variable is consumer buying behavior. Factor analysis, Regression analysis and Reliability analysis are the statistical methods used in this study to analyze the results. Resultshows that usability, interactivity, trust and marketing mix has a positive impact on consumer buying behavior while,classified webs ads are weak in aesthetics area and also lacking in retaining consumer interests in purchasing. After including demographics variables and excluding the limitation of this study for specific area, a researcher could expedite research in a new perspective. The findings of this study contribute in the existing body of knowledge as it is the first case study which targets online medium of purchase in the context of Karachi
Islam: Extremism and Moderation
No full textIslam has, for many years now, been torn between radical fundamentalist groups and the more intellectually moderate groups. With both groups claiming to follow the true Islam, an individual may have a difficult time in practicing one’s faith.
The ambition of this essay will be to investigate some of the major differences between the movements, more specifically the Wahhabi/Salafi movement practiced in Saudi Arabia and the more moderate approach emphasized by numerous Islamic Scholars. Grappling with these issues in my own search for the authentic Islam, this essay will provide a view of both sides with an attempt to justify the moderate position over the strict, literalist one. The intention is to show why the moderate intellectual position is more rooted in Islamic principles and values than the monotonous fanatic position. Due to the many sects, some with more extreme positions like the Khawarij alongside the more rational such as the Mu’tazilites, I decided it would be an enlightening task to break down both sides and challenge the history of both.Peer reviewedstudent peer-reviewed journal articlefinal article publishe
More Than One Path?
No full textIn the minds of many Muslims and non-Muslims the idea of salvation in Islam is quite simple: only Muslims have a chance of attaining paradise and anyone who does not profess to be a Muslim is destined for eternal doom. The ambition of this essay is to argue that from the Islamic point of view, non-Muslims do indeed have a chance of attaining God’s mercy and being saved. This will be argued by taking a look at how the Qur’an accepts diversity, verses in the Qur’an regarding other faiths, along with an explanation and commentary on these verses from some of the most learned scholars on the Qur’an. Also, this essay will look at various Prophetic precedents in Islamic history on this issue.student peer reviewed journal articlefinal article publishe
Doubly-Fed Induction Machine for use in Mini-Hydro Power Plants
No full textElectrical Power EngineeringElectrical Engineering, Mathematics and Computer Scienc
rTMS reduces cortical imbalance associated with visual hallucinations after occipital stroke
No full textThis is an author accepted manuscript of Rafique, S. A., Richards, J. R., & Steeves, J. K. E. (2016). rTMS reduces cortical imbalance associated with visual hallucinations after occipital stroke. Neurology, 87(14), 1493–1500. https://doi.org/10.1212/WNL.0000000000003180Objective: To investigate the efficacy of multiday repetitive transcranial magnetic stimulation (rTMS) to the occipital cortex in a patient with continuous visual phosphene hallucinations for more than 2 years following occipital stroke.
Methods: Low-frequency rTMS (1 Hz) was applied to the lesion site for 30 minutes daily over 5 consecutive days. Functional MRI (fMRI) was performed before and after rTMS treatment.
Results: Increased application of rTMS corresponded with a reduction in intensity of visual phosphene hallucinations and was reflected in altered blood oxygen level–dependent signal. fMRI revealed focal excitatory discharges at the border of the lesion, highlighting the origin of phosphenes. Post-rTMS, rTMS did not simply suppress activity in the patient but rather redistributed the previously imbalanced cortical activity not only at the stimulation site but in remote cortical regions so that it more closely resembled that of controls.
Conclusions: This case is rare in its presentation of chronic continuous visual phosphene hallucinations following occipital stroke. We present a case of multiday application of rTMS to visual cortex and demonstrate that rTMS provides a valuable therapeutic intervention in modulating visual hallucinations following occipital damage.
Classification of evidence: This study provides Class IV evidence in a single-case report that multiday rTMS reduces intrahemispheric and interhemispheric imbalance and associated visual phosphene hallucinations following occipital stroke.Study funded by the Natural Sciences and Engineering Research Council of Canada (grant # 327588) and the Canada Foundation for Innovation (grant # 12807
- …
