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In fusion devices, various techniques are employed for coating the plasma facing components (PFCs) including the vessel wall with low-Z material like lithium, boron, and silicon in order to enhance the plasma parameters and control. In ADITYA-Upgrade tokamak, different techniques of lithium wall conditioning are developed and implemented to obtain uniform and sustainable coating of Li on PFCs and the vessel wall. In this paper, two techniques used to generate Li from the source are reported. In one of the technique, a heated (fixed temperature of ∼120 °C) Li-rod is placed inside the hydrogen glow discharge cleaning (H-GDC) plasma and the sputtered Li by hydrogen (H) ions and atoms coats the wall and periphery. In the second technique, the Li is vapourized using a high-temperature Li-evaporator and released into the H-GDC plasma for uniform coating of Li on the PFCs and vessel. Significantly enhanced plasma parameters are obtained after Li coating by both techniques, with the evaporated Li performed better than the Li rod case. With the Li coating obtained with evaporated Li at 600 °C (550 mg Li) with H-GDC, the Li wall conditioning has been observed to be sustaining for in a larger number of plasma discharges in comparison to non-H-GDC assisted Li deposition. As the melting temperature of lithium hydride (LiH) is much higher (688.7 °C) than that of lithium (180.5 °C), this enhance the longer Li-coating lifetime relatively due to the formation of Liâ€"H molecules on the vessel wall and PFCs. In ADITYA-U the carbon impurity and hydrogen recycling, due to relatively high surface area of graphite PFCs as well as their proximity to the plasma, limits the plasma performance and effective controls. Hence, H-GDC, H-GDC with Li-rod sputtering or Li evaporation, helium-GDC, argonâ€"hydrogen mixtures-GDC in particular sequence are carried out to obtain better plasma discharges. The Li coating techniques and their effect on tokamak plasma discharges of ADITYA-U are discussed in this paper. [ABSTRACT FROM AUTHOR]

Short bursts (∼1 ms) of gas, injecting ∼1017–1018 molecules of hydrogen and/or deuterium, lead to the observation of cold pulse propagation phenomenon in hydrogen plasmas of the ADITYA-U tokamak. After every injection, a sharp increase in the chord-averaged density is observed followed by an increase in the core electron temperature. Simultaneously, the electron density and temperature decrease at the edge. All these observations are characteristics of cold pulse propagation due to the pulsed gas application. The increase in the core temperature is observed to depend on the values of both the chord-averaged plasma density at the instant of gas-injection and the amount of gas injected below a threshold value. Increasing the amount of gas-puff leads to higher increments in the core-density and the core-temperature. Interestingly, the rates of rise of density and temperature remain the same. The gas-puff also leads to a fast decrease in the radially outward electric field together with a rapid increase in the loop-voltage suggesting a reduction in the ion-orbit loss and an increase in Ware-pinch. This may explain the sharp density rise, which remains mostly independent of the toroidal magnetic field and plasma current in the experiment. Application of a subsequent gas-puff before the effect of the previous gas-pulse dies down, leads to an increase in the overall electron density and consequently the energy confinement time. [ABSTRACT FROM AUTHOR]

Oxygen impurity transport in the typical discharges of the Aditya tokamak was investigated using emissivity radial profile of emissivity of the spectral line (2p3p 3D3–2p3d 3F4) at 650.024 nm from the Be-like oxygen ion. This O4+ spectral line was recorded using a 1.0 m multi-track spectrometer capable of simultaneous measurements from eight lines of sight passing through the plasma. The oxygen transport coefficients were determined by reproducing the experimentally measured emissivity profiles of O4+, using a one-dimensional impurity transport code, STRAHL, and photon emissivity coefficient (PEC) belonging to that transition. The PEC values were obtained from both ADAS and NIFS atomic databases. Using both the databases, much higher values of diffusion coefficients compared to the neo-classical values were observed in both high and low magnetic field edge regions of typical Aditya tokamak Ohmic plasma. Although, almost similar profiles of diffusion coefficients were obtained using PEC values from both databases, the magnitude differs considerably. The maximum values of diffusion coefficients in the plasma edge at low field side of tokamak were ~45 and ~25 m2·s−1 when modeling was done using the ADAS and NIFS databases, respectively. Further analysis on the atomic data used in the calculation indicates that the difference in diffusion coefficients is mainly related to the variation in the values of atomic data of the two databases. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) infection is associated with proinflammatory states and adverse health outcomes such as ST-segment elevation myocardial infarction (STEMI) and cerebrovascular accidents (CVA). Limited evidence suggests that COVID-19 vaccination may decrease the adverse impact of COVID-19 infections. This study was designed to determine if patients who received COVID-19 vaccination had lower mortality from STEMI and CVA., Methods: This is a retrospective comparative analysis of 3,050 patients, who were admitted to the hospital and diagnosed with STEMI or CVA between April 1, 2019, and April 1, 2022. Patients were divided into three different timeframes: pre-COVID (April 1, 2019, to March 31, 2020), COVID (April 1, 2020 to March 31, 2021), and post-COVID (April 1, 2021 to March 31, 2022). Chi-square analysis was completed to analyze associations between STEMI, CVA, and vaccination status. A multinominal logistic regression was used to determine significant predictors for in-hospital mortality., Results: A total of 3,050 patients were admitted (1,873 STEMI and 1,177 CVA). STEMI accounted for about 60% of cases in each of the three time periods. There was no statistical difference in STEMI or CVA percentages in the three time periods. There was increased mortality in STEMI and CVA patients (odds ratio (OR) = 11.4; P < 0.001), but patients who received the COVID-19 vaccine were less likely to die (OR = 0.51, 95% confidence interval (CI): 0.28 - 0.93; P < 0.027) when compared to those who were unvaccinated. There was increased risk of death in patients with atrial fibrillation (AFIB) (OR = 2.43; P < 0.001) and chronic heart failure (CHF) (OR = 1.76; P = 0.004). There was increased mortality risk associated with age (OR =1.03; P = 0.001). Patients with coronary artery disease (CAD) (OR = 0.45; P = 0.014) and hyperlipidemia (OR = 0.29; P < 0.001) were less likely to die., Conclusions: Vaccination against COVID-19 was associated with reduced mortality rates in patients hospitalized with STEMI and CVA. Patients with pre-existing cardiovascular comorbidities such as CAD and hyperlipidemia also had lower mortality., Competing Interests: The authors declare there is no conflict of interest., (Copyright 2024, Patel et al.)

We present a unique clinical scenario of a 58-year-old male with a past medical history of hypertension who initially presented with chest pain and was ruled in for non-ST elevation myocardial infarction (NSTEMI) but rapidly developed respiratory failure secondary to aortic insufficiency complicated by cardiogenic shock (CS), attributed to aortic valve prolapse. Intriguingly, the patient had a normal ECG on presentation, underscoring the dynamic nature of valvular pathology. The development of CS highlights the importance of early recognition, prompt diagnosis, and interdisciplinary management in such complex cases., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Kilaru et al.)