Analysis and mitigation of carrier frequency offset for uplink of OFDMA

Orthogonal Frequency Division Multiplexing (OFDM) is being used in many wireless standards because of its immunity to multipath fading, high spectral efficiency and simple implementation, making it suitable for high data rate multimedia wireless applications. One of the significant drawbacks of the OFDM is its sensitivity to Carrier Frequency Offset (CFO). CFO causes Inter Carrier Interference (ICI) between subcarriers and Multiple User Interference (MUI) at Uplink between different users. ICI and MUI at uplink cause significant degradation in the performance of the receiver, therefore, to improve the receiver performance up to acceptable level, compensation of the CFO becomes necessary. In this research, Suppression of MUI by Minimum Mean Squared Error (MMSE) Feedback Equalizer in frequency domain which was originally proposed for Single Carrier- Frequency Domain Multiple Access (SC-FDMA) has been studied for Uplink of Orthogonal Frequency Division Multiple Access (OFDMA). However, calculation of MUI power required in this algorithm for all users impose very high computational burden on the receiver. In the proposed Low Complexity MUI Suppression by MMSE Equalization for Uplink of OFDMA approximation to the calculation of MUI power is applied to reduce its complexity. Simulation result & calculated complexity show that proposed method obtains good performance with much lower complexity

Cost analysis of antiretroviral agents available in India

Background: AIDS is one of the most prevalent causes of death due to infectious origin which requires a lifelong therapy. There is variation in prices of antiretroviral drugs available in Indian market. Thus, a study was planned to find out variation in prices of antiretroviral drugs either as a single drug or in combination and to evaluate the difference in cost of various brands of the same antiretroviral drugs by calculating percentage variation in cost in Indian rupees.Methods: Cost of antiretroviral drugs manufactured by different pharmaceutical companies, in the same strength and dosage forms was obtained from “Current Index of Medical Specialties” July-October 2014 and “Indian Drug Review” Vol. XXI, Issue No. 4, 2014. The difference in the maximum and minimum price of the same drug manufactured by different pharmaceutical companies and percentage variation in cost was calculated.Results: Percentage variation in cost for antiretroviral drugs marketed in India was found to be zidovudine (100 mg) - 436%, lamivudine (100 mg) - 268%, tenofovir (300 mg) - 149.5%, didanosine (250 mg) - 73.75%, indinavir (400 mg) - 35.26%. Among the combination therapy, price variation was lamivudine + zidovudine (150 + 300 mg) - 314%, lamivudine + stavudine (150 + 40 mg) - 105%, lopinavir + ritonavir (133.3 + 33 mg) - 25%.Conclusion: There is wide variation in the prices of antiretroviral agents available in the market. Regulatory authorities, pharma companies, physicians should maximize their efforts to reduce the cost of drugs

Cure of human immunodeficiency virus/acquired immune deficiency syndrome: promising future prospects at horizon

Acquired immune deficiency syndrome (AIDS) is a disease caused by humanimmunodeficiency virus and characterized by profound immunosuppression thatleads to opportunistic infections, secondary neoplasms, and neurologic complications.AIDS is among the leading causes of death worldwide. Current therapeutic optionsare directed only toward management of AIDS, but not toward its prevention or cure.In addition, it also possesses numerous problems like drug resistance, drug toxicity,drug interactions, non-adherence to therapy, life-long and expensive treatment, etc.Recent years in drug development have shown promising prospects for prevention/treatment/cure of AIDS like histone deacetylase inhibitors, Vpu ion channel inhibitors,viral decay acceleration, maturation inhibitors, tat antagonists, gene/stem cell therapy,and antiretroviral vaccines

Post COVID sequelae among COVID-19 survivors: insights from the Indian National Clinical Registry for COVID-19

Introduction The effects of COVID-19 infection persist beyond the active phase. Comprehensive description and analysis of the post COVID sequelae in various population groups are critical to minimise the long-term morbidity and mortality associated with COVID-19. This analysis was conducted with an objective to estimate the frequency of post COVID sequelae and subsequently, design a framework for holistic management of post COVID morbidities.Methods Follow-up data collected as part of a registry-based observational study in 31 hospitals across India since September 2020–October 2022 were used for analysis. All consenting hospitalised patients with COVID-19 are telephonically followed up for up to 1 year post-discharge, using a prestructured form focused on symptom reporting.Results Dyspnoea, fatigue and mental health issues were reported among 18.6%, 10.5% and 9.3% of the 8042 participants at first follow-up of 30–60 days post-discharge, respectively, which reduced to 11.9%, 6.6% and 9%, respectively, at 1-year follow-up in 2192 participants. Patients who died within 90 days post-discharge were significantly older (adjusted OR (aOR): 1.02, 95% CI: 1.01, 1.03), with at least one comorbidity (aOR: 1.76, 95% CI: 1.31, 2.35), and a higher proportion had required intensive care unit admission during the initial hospitalisation due to COVID-19 (aOR: 1.49, 95% CI: 1.08, 2.06) and were discharged at WHO ordinal scale 6–7 (aOR: 49.13 95% CI: 25.43, 94.92). Anti-SARS-CoV-2 vaccination (at least one dose) was protective against such post-discharge mortality (aOR: 0.19, 95% CI: 0.01, 0.03).Conclusion Hospitalised patients with COVID-19 experience a variety of long-term sequelae after discharge from hospitals which persists although in reduced proportions until 12 months post-discharge. Developing a holistic management framework with engagement of care outreach workers as well as teleconsultation is a way forward in effective management of post COVID morbidities as well as reducing mortality

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)