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Normal dispersion decreasing fibers (NDDFs) employed for parabolic pulse (PP) generation are limited by the presence of inherent third-order dispersion (TOD), which leads to distortion in pulse shape from its parabolic nature. This necessitates a compensation method for TOD for such fibers. Dispersion-compensating fiber (DCF) amplifiers with relatively smaller values of dispersion can also be largely affected by this harmful effect of TOD when used for the same purpose. As a solution, a time-reversal system (TRS) based on a time-conjugating technique is employed with the aim of minimizing the deleterious effects of TOD. A detailed study on the estimation of the critical length where the time lens system needs to be implemented within the fiber link is crucial for reshaping the pulse into parabolic form. An NDDF is designed and optimized to possess a relatively higher value of TOD and a cascaded fiber optic system comprising the first stage of the proposed NDDF, the TRS and the second stage of the NDDF is suggested here to obtain linearly chirped PP at the output end even in the presence of a high value of TOD. The proposed scheme has also proved to be efficient for better pulse reshaping through DCFs possessing a high amount of TOD. [ABSTRACT FROM AUTHOR]

This paper describes experimental data on a polycrystalline nickel subjected to compressive loads induced in a split Hopkinson pressure bar test. A perpendicular bias magnetic field with respect to the loading direction is used to orient the domains and a pick-up coil measures the magnetic response of the sample during loading. Utilizing this experimental configuration, this study investigated the coupled effects of the magnetic and mechanical fields on domain wall motion in a polycrystalline magnetostrictive material (Ni) during the high-rate elastic loading. The experimental measurements reveal that the magnitude of the stress-induced magnetization change is dependent upon bias magnetic field. [ABSTRACT FROM AUTHOR]

This work reports on the significance of reducing channel doping and optimizing the spacer width to enhance analog/RF metrics of junctionless (JL) MOSFETs for operation at low current levels (∼30 μA μm−1). It is shown that optimally designed junctionless devices achieve 40–50% higher cut-off frequency (fT) and maximum oscillation frequency (fMAX), along with a 15% enhancement in intrinsic voltage gain (AVO) as compared to conventional junctionless (JL) transistors designed with a channel doping (Nd) of 1019 cm−3. The parasitic fringing capacitances are significantly reduced in optimized JL devices. The gain-bandwidth trade-off can be considerably improved around the analog ‘sweet spot’ as performance metrics are enhanced by 70–90%. Apart from the above benefits, the optimal JL design results in reduced sensitivity to variation in device parameters. Results will be useful for design and optimization of low power junctionless MOSFETs for analog/RF applications. [ABSTRACT FROM AUTHOR]

Objectives: The presentation and outcomes of acute decompensated heart failure (ADHF) during COVID times (June 2020 to Dec 2020) were compared with the historical control during the same period in 2019., Methods: Data of 4806 consecutive patients of acute HF admitted in 22 centres in the country were collected during this period. The admission patterns, aetiology, outcomes, prescription of guideline-directed medical therapy (GDMT) and interventions were analysed in this retrospective study., Results: Admissions for acute heart failure during the pandemic period in 2020 decreased by 20% compared to the corresponding six-month period in 2019, with numbers dropping from 2675 to 2131. However, no difference in the epidemiology was seen. The mean age of presentation in 2019 was 61.75 (±13.7) years, and 59.97 (±14.6) years in 2020. There was a significant decrease in the mean age of presentation (p = 0.001). Also. the proportion of male patients decreased significantly from 68.67% to 65.84% (p = 0.037). The in-hospital mortality for acute heart failure did not differ significantly between 2019 and 2020 (4.19% and 4.,97%) respectively (p = 0.19). The proportion of patients with HFrEF did not change in 2020 compared to 2019 (76.82% vs 75.74%, respectively). The average duration of hospital stay was 6.5 days., Conclusion: The outcomes of ADHF patients admitted during the Covid pandemic did not differ significantly. The length of hospital stay remained the same. The study highlighted the sub-optimal use of GDMT, though slightly improving over the last few years., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: ALL PARTICIPATING CENTRE CO INVESTIGATORS reports financial support was provided by Cardiological Society of India., (Copyright © 2023 Cardiological Society of India. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.)

Objective: To find out differences in the presentation, management and outcomes of COVID-19 infected STEMI patients compared to age and sex-matched non-infected STEMI patients treated during the same period., Methods: This was a retrospective multicentre observational registry in which we collected data of COVID-19 positive STEMI patients from selected tertiary care hospitals across India. For every COVID-19 positive STEMI patient, two age and sex-matched COVID-19 negative STEMI patients were enrolled as control. The primary endpoint was a composite of in-hospital mortality, re-infarction, heart failure, and stroke., Results: 410 COVID-19 positive STEMI cases were compared with 799 COVID-19 negative STEMI cases. The composite of death/reinfarction/stroke/heart failure was significantly higher among the COVID-19 positive STEMI patients compared with COVID-19 negative STEMI cases (27.1% vs 20.7% p value = 0.01); though mortality rate did not differ significantly (8.0% vs 5.8% p value = 0.13). Significantly lower proportion of COVID-19 positive STEMI patients received reperfusion treatment and primary PCI (60.7% vs 71.1% p value=< 0.001 and 15.4% vs 23.4% p value = 0.001 respectively). Rate of systematic early PCI (pharmaco-invasive treatment) was significantly lower in the COVID-19 positive group compared with COVID-19 negative group. There was no difference in the prevalence of high thrombus burden (14.5% and 12.0% p value = 0.55 among COVID-19 positive and negative patients respectively) CONCLUSIONS: In this large registry of STEMI patients, we did not find significant excess in in-hospital mortality among COVID-19 co-infected patients compared with non-infected patients despite lower rate of primary PCI and reperfusion treatment, though composite of in-hospital mortality, re-infarction, stroke and heart failure was higher., (Copyright © 2023 Cardiological Society of India. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.)

Right ventricular (RV) pacing is associated with a reduction in left ventricular (LV) systolic function, thought to be mediated by pacing-induced ventricular dyssynchrony. The prevalence of heart failure after RV pacing is reported to range from 31±3%. We studied 60 subjects with high-grade atrioventricular block and Complete Heart Block (CHB) scheduled to undergo right ventricular apical pacing. 2D echocardiography was done at baseline, 1 month and 12 months. Pacing-induced cardiomyopathy was defined as a reduction in LVEF to <45%. Strain was evaluated off-line from digitally stored images using all advanced software package (cardiac wall motion quantification (CMQ); Toshiba Medical Systems). Longitudinal strain for individual myocardial segments was measured from the apical four-chamber, two-chamber and long axis views (16 segment AHA/ASE model). None had LV dysfunction at baseline based on 2D and strain echo imaging. Subsequently 18 patients were detected to develop low GLS score (less than -14.5) at 1 month. On subsequent follow up at 1 year, all 18 patients developed LV dysfunction on 2D Echocardiography. Thus Strain imaging with GLS score helped in early detection of LV dysfunction in RV apical pacing subjects. Pacing-induced cardiomyopathy had significant association with high grade AV block with pacemaker dependency. It had no significant associations with other comorbidities like diabetes, hypertension, ischemic heart disease or with the type of medication intake. However there was a statistically significant association with heart failure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Cardiological Society of India. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.)

Ambulatory blood pressure monitoring provides a more reliable assessment of actual BP than office BP and is a more sensitive risk predictor of clinical cardiovascular outcomes. Recent international guidelines for hypertension have emphasised the usefulness of ambulatory BP for diagnosis and management of hypertension. We used ambulatory blood pressure monitoring to monitor the effect of the pharmacological treatment in patients with stage 1 or 2 hypertension. This was a multicentric randomised controlled trial having 360 subjects with 180 in each treatment arm. The duration of study was 6 months. The patients were randomly selected to receive atenolol or losartan as initial therapy. The dose of atenolol or losartan was 50 mg once daily at 8 am in the morning. Ambulatory BP assessment was done in a subgroup of subjects using Schiller BR-102 plus machine. One hundred and thirty patients were recruited for the study using ambulatory blood pressure monitoring. There were 66 patients in atenolol arm and 64 patients in the losartan arm. A significant white coat hypertension was noticed in both the arms. Out of 130 subjects in the ambulatory group, 41.53% had a white coat hypertension. Statistically significant reduction of office BP was observed with both atenolol and losartan; however, no significant difference in efficacy of the two drugs was found in reducing office BP. However, when using ambulatory blood pressure monitoring, the reduction with either drug was not significant. The dipper status was better in the atenolol group than the losartan group. Neither of the drugs prevent morning surge of BP when administered once daily in the morning. There was high prevalence of white coat hypertension in patients with stage 1 and stage 2 hypertension. There was similar reduction of systolic blood pressure and diastolic blood pressure by the 2 study drugs. Atenolol scores over losartan in converting non-dipper to dipper but its' impact on clinical outcome is not known. Morning surge of BP was unaffected by either of the study drugs.

Primary ciliary dyskinesia (PCD) is an autosomal recessive heterogeneous group of conditions with variable clinical findings like recurrent respiratory tract infections, bronchiectasis, situs inversus, singly or in various combinations. Development of Pulmonary arterial hypertension can be a late complication of this disease. Here we present a case of PCD with recurrent respiratory tract infections, bronchiectasis and severe PAH, who responded to treatment with Oxygen, IV broad spectrum antibiotics and oral sildenafil.

Hypertension is a common clinical problem with great implications for public health. It is a silent killer and often remains asymptomatic. So regular BP check-up is a must. Complications of untreated hypertension include ventricular hypertrophy, heart failure and accelerated atherosclerosis, cerebrovascular disease and stroke, renal failure and retinopathy. Primary care physicians have immense duty to perform in this regard because they are the first to encounter them in various stages of the disease. Hypertension can present per se or in emergencies (as in crisis) or in disguise of a complication (like anaemia and renal failure). Control of hypertension and delaying the development of complications should be their first goal. Lastly, some hypertensives with complications may require referral to advanced centres.