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Abstract Conjugated polymers need to be doped to increase charge carrier density and reach the electrical conductivity necessary for electronic and energy applications. While doping increases carrier density, Coulomb interactions between the dopant molecules and the localized carriers are poorly screened, causing broadening and a heavy tail in the electronic density‐of‐states (DOS). The authors examine the effects of dopant‐induced disorder on two complimentary charge transport properties of semiconducting polymers, the Seebeck coefficient and electrical conductivity, and demonstrate a way to mitigate them. Their simulations, based on a modified Gaussian disorder model with Miller‐Abrahams hopping rates, show that dopant‐induced broadening of the DOS negatively impacts the Seebeck coefficient versus electrical conductivity trade‐off curve. Increasing the dielectric permittivity of the polymer mitigates dopant‐carrier Coulomb interactions and improves charge transport, evidenced by simultaneous increases in conductivity and the Seebeck coefficient. They verified this increase experimentally in iodine‐doped P3HT and P3HT blended with barium titanate (BaTiO3) nanoparticles. The addition of 2% w/w BaTiO3 nanoparticles increased conductivity and Seebeck across a broad range of doping, resulting in a fourfold increase in power factor. Thus, these results show a promising path forward to reduce the dopant‐charge carrier Coulomb interactions and mitigate their adverse impact on charge transport.

Introduction: We compare the outcomes of three different diuretic protocols for renograms in children with hydronephrosis. Materials and Methods: Between August 2011 and July 2013, 148 diuretic renograms were performed to evaluate unilateral grade 3-4 hydronephrosis (reflux, posterior urethral valves, post-pyeloplasty status excluded). Patients were allotted into three groups based on the timing of diuretic administration: Diuretic given 15 min before (F-15), at the same time as (F + 0) and 20 min after (F + 20) radionuclide administration. Dynamic images and renogram curves were inspected to identify in each group (1) number of equivocal curves and (2) number of interrupted studies due to patient movement/discomfort/voiding. Statistical significance was determined by the Fisher exact test. Results: There was no significant difference in age/sex distribution between groups F-15 (n = 35), F + 0 (n = 38) and F + 20 (n = 75). The number of equivocal curves was significantly less in F + 0 (2/38) and F-15 (3/35) compared with F + 20 (20/75). The number of interrupted studies was significantly less in F + 0 (2/38) compared with F-15 (9/35) and F + 20 (18/75). Conclusion: The F + 0 and F-15 protocols are superior to the F + 20 protocol in reducing the number of equivocal curves, while the F + 0 protocol is superior to the other two in reducing interruptions due to patient movement or voiding. F + 0 is the diuretic protocol of choice for renogram in children.

Background: Several cardiac biomarkers are being studied to explore their potential in the prognostication of Acute Coronary Syndrome (ACS). However, there are limited studies exploring the relationship between these biomarkers and clinical, laboratory and demographic characteristics., Objective: We sought to determine the factors which influence the concentration of novel cardiac biomarkers such as Galectin-3, suppression of tumorigenicity-2 (ST-2) and Matrix Metallopeptidase-9 (MMP-9) in patients with ACS., Methods: A total of 122 patients with ACS were enrolled in the study. The study patients were categorized into two groups namely: STEMI (n=58) and NSTEMI/UA (n=64). Plasma samples were used to determine the level of biomarkers, Galectin-3 and ST-2, and serum samples were used to determine the levels of MMP-9 using the Enzyme-linked immunosorbent assay (ELISA). The association between the plasma and serum levels of biomarkers and, demographic, clinical and laboratory variables were determined. Statistical analyses for the study were performed using SPSS 16.0 software (SPSS Inc., Chicago, IL, USA)., Results: Elderly aged [0.107 (0.012-0.969); p=0.047] patients had higher ST-2. Galectin-3 was higher among female patients [3.693(1.253-10.887); p=0.018] and patients with low left ventricular ejection fraction [2.882 (1.041-7.978); p=0.042]. Patients with lower body mass index [3.385 (1.241-9.231); p=0.017], diabetes [3.650 (1.302-10.237); p=0.014] and high total leukocyte count [2.900 (1.114-7.551; p=0.029] had higher MMP-9 levels., Conclusion: The concentration of galectin-3, ST-2 and MMP-9 are independently influenced by demographic, clinical and laboratory characteristics. It is estimated that these factors should be accounted for when interpreting the results of the biomarker assays., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Acute coronary syndrome (ACS) patients are at an increased risk of major adverse cardiovascular events (MACE). The objective of our study was to assess whether cardiac biomarker like soluble ST2 (sST2) can predict MACE among ACS patients with diabetes., Materials and Methods: A total of 122 patients with ACS were included in the study. sST2 level in blood plasma samples was quantified using enzyme-linked immunosorbent assay (ELISA). Prognostic utility of sST2 for the primary outcome of MACE which included mortality, rehospitalization due to chest pain, unstable angina, recurrent myocardial infarction (MI) and stroke, was assessed during follow-up., Results: The median follow-up period was of 180 days. ROC (receiver operating characteristic) curve demonstrated that elevated levels of sST2 were able to predict mortality, and MACE in ACS patients, along with increased risk of occurrence of MACE and mortality in ACS patients having diabetes. Kaplan-Meier plots revealed a significant increase in the occurrence of MACE in diabetic ACS patients (P = 0.006; by log-rank test). Cox regression analysis revealed that sST2 is not an independent predictor of mortality and MACE in ACS patients having diabetes; however, high sST2 level was found to be a predictor of MACE in all ACS subjects in the fully adjusted model with a hazard ratio (HR) of 5.8 (P = 0.032)., Conclusion: The current study indicates that elevated levels of sST2 might be a suitable biomarker to evaluate the risk of future adverse cardiovascular events in ACS patients with diabetes., (© 2018 Stichting European Society for Clinical Investigation Journal Foundation.)

Background: Microparticles (MP) are a nuclear fragments of membrane released by the damaged cell during stress. Elevated levels of MP have been found in patients with acute coronary syndrome (ACS) owing to the damage in the endothelium., Aim: To determine if the levels of endothelial and platelet microparticles (EMP & PMP) in patients with ACS influenced the severity of the disease., Materials and Methods: This was a prospective cohort study performed in 63 ACS patients (ST elevation myocardial infarction- STEMI-28, non ST elevation myocardial infarction -NSTEMI-35). After obtaining consent, blood samples were collected from the patients and processed by flow cytometry., Results: The NSTEMI group had higher levels of EMP {792.11(327.59-1661.49) vs 300.35 (176.3-550.46), p=0.001} and PMP {218.87(86.65-439.77) vs 114.45(50.34-196.75), p= 0.007} as compared to the STEMI group. However, it was found that the EMP (r=-0.438, p=0.001) and PMP (r= -0.316, p=0.024) negatively correlated with Global Registry of Acute Coronary Events score (GRACE in-hospital score) for the entire cohort., Conclusion: The levels of microparticles are elevated in ACS patients and may reflect a protective effect in patients with acute coronary syndrome.

Objective: The present study was designed to derive the normal limits of a new ECG lead system aimed at enhancing the amplitude of atrial potentials through the use of bipolar chest leads., Methods: Sixty healthy male subjects, mean age 38.85±8.76 years (range 25 to 58 years) were included in this study. In addition to a standard 12-lead ECG, a modified limb lead (MLL) ECG was recorded for 60 sec with the RA electrode placed in the 3rd right intercostal space slightly to the left of the mid-clavicular line, the LA electrode placed in the 5th right intercostal space slightly to the right of the mid-clavicular line and the LL electrode placed in the 5th right intercostal space on the mid- clavicular line., Results: In the frontal plane, the modification of limb electrode positions produced significant changes compared to standard limb lead I and II. The mean P wave amplitude was 111±17μV in MLL I and 64±16μV in standard limb lead (SLL) I (p<0.001). Similarly it was 118±22μV in MLL II and 100±27μV in SLL II. No statistically significant changes were seen in V1-V6 due to modification of the Wilson central terminal electrode positions., Conclusion: The modification of limb electrode placement leads to changes in the amplitude of the P waves in the MLL leads I and II compared to SLL leads I and II in healthy subjects. These changes may be of importance in the detection of atrial electrical activity.

Congenital mitral stenosis (MS) is a rare congenital cardiac malformation and the obstruction to the flow across the mitral valve can be caused by supramitral ring, commissural fusion, short chordae, anomalous mitral arcade, anomalous position of the papillary muscles and the so-called'parachute mitral valve'. We describe here the case of a 47 year old male diagnosed to have a double outlet right ventricle (DORV), subaortic ventricular septal defect (VSD) with no pulmonary stenosis, severe pulmonary hypertension and congenital MS due to parachute mitral valve.

Background: The close relationship between pleural space and pericardial space and the dependence of their pressure kinetics are well known. This study evaluates the effects of increased intra pleural pressure due to pleural effusion on cardiovascular system., Methods: Forty patients above the age of 12 who had massive unilateral/bilateral pleural effusion due to non-cardiac etiology were included in the study. Therapeutic thoracocentesis was done for massive pleural effusion. The echocardiographic parameters measured before and after thoracocentesis were compared., Results: Mean age of the patients 46.6 years. Out of 40 patients 8 were females (20%). 7 patients had right atrial collapse on echo. 85% of patients had significant flow velocity changes across both tricuspid valve and mitral valve during phases of respiration.11 patients (47.82%) had IVC compressibility of <50% during inspiration. Mean flow velocity respiratory variations across tricuspid valve before thoracocentesis and after thoracocentesis E 45.04 ± 10.3,32 ± 11.3% (p value <0.001), A 53.71 ± 28%, 32.08 ± 12.5% (p < 0.001) across mitral valve E 32.30 ± 12%, 19.78 ± 7.8% (p < 0.001), A 26 ± 11.2%, 21 ± 9.3% (p 0.006) across pulmonary artery 42.63 ± 31.3%, 17.70 ± 6.2% (p < 0.001), across aorta 21.57 ± 11.4%, 14.08 ± 7.6% (p < 0.001)., Conclusion: Large pleural effusion has a potential to cause adverse impact on the cardiovascular hemodynamics, which could manifest as tamponade physiology. Altered cardiac hemodynamics could be an important contributor in the mechanism of dyspnea in patients with large pleural effusion., (Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Left atrial thrombus in the presence of diseased mitral valve and atrial fibrillation is a well known entity. But it is very rare to occur in the presence of normal mitral valve apparatus. We report the case of a 36 year old female who presented with left atrial ball valve thrombus and normal mitral valve apparatus and underwent surgery. This patient with gangrene of right lower limb came for cardiac evaluation. She had infarct in left middle cerebral artery territory- ten months prior to this admission and was on treatment for infertility. She had atrial fibrillation. Emergency surgery to remove the thrombus should be considered given its potential life threatening embolic nature., (Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)