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Four hot-gas bypass defrosting configurations for CO2-NH3 cascade blast freezer for application in fish processing firm are numerically investigated. Due to the high moisture content of fish, defrosting is necessary after every 4 to 5 h of batch operation. A thermodynamic model for the cascade system and defrosting was developed to study various defrosting configurations formulated by rearranging the existing compressor to operate as a defrosting compressor and with the addition of an external defrosting compressor. From the simulation findings, it can be summarized that the conventional hot-gas bypass defrosting without defrost compressor is suitable for a high-capacity cascade refrigeration system with more than three evaporators. For low cooling capacity refrigeration systems, a defrosting compressor is necessary to elevate the temperature above the cascade condensing temperature. A dedicated defrosting compressor with a power consumption of 3.1 kW and a modified refrigeration/defrosting compressor with a power consumption of 6.8 kW can deliver 33.3 kW of heating at a temperature of +10 °C (45 bar). Incorporating a desuperheater between the main and defrosting compressors reduces compressor temperature and maintains the lubricating oil stability, without change in defrosting energy consumption and less exergy loss. The defrosting efficiency is obtained in the range of 39.7–42% which is in agreement with published literature. [ABSTRACT FROM AUTHOR]

Objective: Ischemic heart disease is the leading cause of mortality in population above the age of 70 years. ST-elevation myocardial infarction (STEMI) constitutes important treatable cause of death in elderly population. However, many large, randomized trials have excluded this age group. The present study was planned to find out the benefits and complications related to thrombolytic therapy in elderly patients. Materials and Methods: The study was done between January 1, 2019, and December 31, 2019, in the Department of Cardiology, Sri Jayadeva Institute Of Cardiovascular Sciences and Research, Bengaluru, India, which included the study group comprising 106 elderly patients (age >70 years) with acute STEMI and underwent thrombolytic therapy. All patients were followed up till the index hospitalization and evaluated for in-hospital outcome. Results: Out of the 106 patients in the study group, 64 (60.38%) were male and 42 (39.62%) were female. Out of which, 88 (83%) patients were between 70 and 80 years whereas 18 (17%) patients were >80 years. Mortality was happened in 32 patients (30.2%). Coronary angiogram post thrombolysis was performed as pharmacoinvasive or rescue percutaneous coronary intervention (PCI) in 25 patients (23.6%), and cardiac arrhythmias were noted in 22 (20.6%) patients, acute kidney injury in 7 (6.6%) patients, ventricular septal rupture in 5.7%, ischemic stroke in 4.7%, free-wall rupture in 2.8%, and intracranial hemorrhage in 0.9% of patients. Conclusions: Primary PCI may offer clinical advantage over fibrinolytic therapy as manifested by the trends toward improvements in the combined endpoint of death, reinfarction, and stroke in the oldest patients. Despite the higher prevalence of comorbidities and high-risk features in elderly patients of acute STEMI, timely thrombolysis is also beneficial particularly who present early after symptom onset, absence of comorbid condition, and lower NYHA class on admission (NYHA I/II). In developing countries like India where primary PCI may not be feasible, timely thrombolysis should be given to the elderly patients also. [ABSTRACT FROM AUTHOR]

This paper presents fabrication of an ultrasonic regenerative evaporative cooler, coupled with a desiccant dehumidifier. Ultrasonic regenerative evaporative cooler consists of several sets of a dry channel and a wet channel. A part of the air from the dry channel is redirected into the wet channel where it is cooled by evaporation of water mist from an ultrasonic atomiser. Air flowing through dry channels is pre-cooled by heat transfer between wet and dry channels, without changing its humidity. In this cooler, the conventional hygroscopic layer for wetting the plate surface is replaced with the water mist. It is observed that the performance of the cooling system significantly depends on the channel spacing, channel length, inlet airflow rate and extraction ratio, and marginally depends upon feed water temperature. The room cooling capacity is eminently responsive to both air mass flow rate and extraction ratio. The maximum available room cooling capacity of 339.8 W is obtained for the optimal values of 0.0488 kg/s mass flow rate of air and 0.37 extraction ratio. The prototype achieved wet-bulb effectiveness values as high as 1.15 and delivered more than 10℃ temperature drop.Practical application: An ultrasonic regenerative evaporative cooler can be coupled with a desiccant dehumidification unit for use in hot and humid climate to achieve comfort condition utilising less energy and feed water when compared to the vapour compression refrigeration system. From this prototype researchers and engineers can develop, by combining desiccant regenerators and evaporative coolers which use ultrasonic method for low-temperature dehydration of desiccant substance. Solar thermal energy can also be directly utilised for marginally heating the desiccant substance during the regeneration process. Overall, this system can contribute to the development of energy efficient buildings. [ABSTRACT FROM AUTHOR]

Coronary arteries anomalies are rare. We report a case of anterior wall myocardial infarction with anomalous left anterior descending artery (LAD) and left circumflex artery (LCX), with LAD originating from right coronary sinus and LCX from right coronary artery. We did successful percutaneous coronary intervention with stenting to LAD using Amplatzer AR1-catheter. [ABSTRACT FROM AUTHOR]

Introduction: It has been observed that metabolic syndrome is risk factor for Coronary Artery Disease (CAD) and exerts its effects through fat deposition and vascular aging. CAD has been acknowledged as a leading cause of death. In earlier studies, the metabolic risk has been estimated by Framingham's risk score. Recent studies have shown that Neck Circumference (NC) has a good correlation with other traditional anthropometric measurements and can be used as marker of obesity. It also correlates with Framingham's risk score, which is slightly more sophisticated measure of CAD risk. Aim: To assess the risk of CAD in a subject based on NC and to correlate the NC to Framingham's risk score. Materials and Methods: The present cross-sectional study, done at Karnataka Institute of Medical Sciences, Hubli, Karnatka, India, includes 100 subjects. The study duration was of one year from 1st January 2015 to 31st December 2015. Anthropometric indices Body Mass Index (BMI) and NC were correlated with 10 year CAD risk as calculated by Framingham's risk score. The correlation between BMI, NC, vascular age and Framingham's risk score was calculated using Karl Pearson's correlation method. Results: NC has a strong correlation with 10 year CAD risk (p=0.001). NC was significantly greater in males as compared to females (p=0.001). Males had greater risk of cardiovascular disease as reflected by higher 10 year Framingham's risk score (p=0.0035). Conclusion: NC gives simple and easy prediction of CAD risk and is more reliable than traditional risk markers like BMI. NC correlates positively with 10 year Framingham risk score. [ABSTRACT FROM AUTHOR]

Introduction: Coronary angiography is the gold standard for quantification of coronary atherosclerosis. But, being invasive, it has inherent complications. Hence, we examined the accuracy of prediction of coronary angiography using simple anthropometric indices. Aim: To identify a patient friendly method to predict coronary artery disease using simple anthropometric parameters, by testing their correlation with coronary artery disease severity scoring system. Materials and Methods: We conducted a cross-sectional study on patients undergoing elective coronary angiography. A total of 48 patients were included in the study. Neck circumference and leg length of the patients were noted. The severity of coronary atherosclerosis was quantified using Jenkin's scoring system. Mean and standard deviation for each continuous variable was calculated. The correlation between Jenkins' score, neck circumference and leg length was tested. The data analysis was done using IBM-SPSS software. Results: Mean leg length among the study population was 88.70 cm (±2.51 cm) among males, 79.04 cm (±4.32 cm) among females and 83.66 cm (±3.26 cm) overall. Mean neck circumference was 36.87 cm (±4.37 cm) among males, 36.04 cm (±3.65 cm) among females and 36.44 cm (±3.99 cm) when combined together. There was no correlation of Jenkin's scores with leg length. But, there was significant correlation between Jenkin's scores and neck circumference. Conclusion: Neck circumference can be used as a simple and effective tool and is better than leg length for risk stratification of patients with coronary heart disease. [ABSTRACT FROM AUTHOR]

Atmospheric aerosols have a serious impact on altering the radiation balance of the vulnerable Himalayan atmosphere. Organic aerosol (OA), one of the least resolved aerosol fractions in the Himalayas, constrain our competence to assess their climate impacts on the region. Here we investigate water-soluble OA molecules in PM 10 samples collected from March to May 2019 at Lachung (27.4°N and 88.4°E), a high-altitude location (2700 m a.s.l.) in the eastern Himalaya, to elucidate their origin and formation process. The dominance of oxalic acid (C 2 ) reveals that water-soluble OA in the eastern Himalaya are atmospherically processed. Backward air mass trajectories and mass concentration ratios of organic tracers as well as relationships with inorganic species (K + , SO 4 2- , NH 4 + ) suggest an anthropogenic origin of water-soluble OA with significant atmospheric processing during long-range transport to the eastern Himalayan region. We used the thermodynamic prediction of aerosol liquid water (ALW) to examine the formation mechanism of secondary OA (SOA) such as oxalic acid. Correlations of ALW with SO 4 2- and water-soluble organic matter show that ALW is sensitive to both anthropogenic sulfate and water-soluble organic compounds in Himalayan aerosols. A strong positive relationship of C 2 acid with predicted ALW provides evidence of extensive SOA formation from precursors via aqueous phase photochemical processes. This inference is supported by positive correlations of C 2 acid relative abundance with diagnostic mass concentration ratios of C 2 acid to precursor molecules. Our findings underscore the importance of anthropogenic sources and ALW in SOA formation through aqueous phase processes in the eastern Himalaya., 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 © 2024 Elsevier B.V. All rights reserved.)

Tropical coastal regions may provide a unique feature to study the photooxidation of various organic aerosols and their climatic effects because of high humid atmosphere and intense solar radiation. However, knowledge about organic molecular composition and its light absorption properties remains concealed, particularly over tropical Indian regions. The present study is an investigation on water-soluble dicarboxylic acids, ω-oxoacids, pyruvic acid, α-dicarbonyls, brown carbon (BrC), and other chemical species in PM 1.1 collected at a coastal urban location (Kochi) on the west coast of tropical India under distinct air masses. Molecular distribution of dicarboxylic acids was characterized by the predominance of oxalic acid (C 2 ) in all the air masses followed by adipic (C 6 ) or terephthalic (tPh) and phthalic (Ph) acids. On average, total diacids-C accounted for 5.03 ± 1.01 % of TC. Total diacid concentration showed strong linear relationships with organic (OC), elemental carbon (EC), and non-sea-salt potassium (nss-K + ). Except for the northwest (NW) air mass period, the concentration of C 2 diacid and its ratios (C 2 /total diacids, C 2 /ωC 2 , C 2 /Gly) showed a strong linear relationship with nss-SO 4 . By combining all these results together with Pearson correlation analysis, the present study demonstrates that organic aerosols over the study region were predominantly produced by aqueous-phase oxidation of precursor compounds derived from biomass burning and combustion-related emissions. The mass absorption coefficient of BrC (b 2- . By combining all these results together with Pearson correlation analysis, the present study demonstrates that organic aerosols over the study region were predominantly produced by aqueous-phase oxidation of precursor compounds derived from biomass burning and combustion-related emissions. The mass absorption coefficient of BrC (b abs-BrC-365nm ) was strongly correlated with nss-K + , implying that biomass burning emissions are major sources of BrC. The absorption angstrom exponent (AÅE) values of water (methanol) extracts ranged from 3.20 to 3.83 (3.05-4.55) during the entire sampling period, indicating the substantial contribution of BrC chromophores to light absorption over the region. On average, BrC absorbs 10.6 ± 6.4 % and 22.4 ± 5.75 % of solar radiation compared to BC in water and methanol extracts, respectively, suggesting that BrC is a significant aerosol climate forcing agent over the west coast of tropical India., 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 © 2022 Elsevier B.V. All rights reserved.)

Objective: To study the significance of ST-segment depression during 'recovery' compared to that 'during stress' and 'both the phases' in exercise stress test., Methods: Patients with positive exercise stress test who underwent coronary angiography (CAG) from 1st January 2017 to 31st December 2018 were studied. Patients were divided into 3 groups- Group A with ST-depression restricted to recovery phase, group B with ST-depression restricted to stress phase and group C with ST-depression seen both during exercise and recovery. All patients underwent CAG. Sensitivity, specificity, and predictive values of each of these groups in diagnosis of significant coronary artery disease (CAD) were analysed and compared., Results: Total 300 patients were studied. Mean age of the study population was 48.77 ± 7.94 years. 78.3% of patients with positive exercise stress test had significant CAD. 96% of patients in group A had significant CAD, which was higher than in group B (88.9%) & group C (70.1%). The specificity, positive predictive value and negative predictive value of ST-segment depression in group A (96.92%, 96% and 25.2% respectively) were higher than that of ST-depression in group B (89.23%, 88.89% and 24.47% respectively) and group C (13.85%, 70.05% and 7.96% respectively). Sensitivity and accuracy of ST-depression in group A were lower (20.43% and 37% respectively), compared to other 2 groups., Conclusion: Patient with ST-depression restricted to recovery phase had highest specificity, positive predictive value, and negative predictive value. However, accuracy was highest in group with both stress phase and exercise ST-segment depression., Competing Interests: Declaration of competing interest All author has none to declare., (Copyright © 2021 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Pulmonary hypertension (PH) is a recently recognized complication of chronic kidney disease (CKD), especially in end-stage renal disease. It has prevalence estimates of 30%-50% and is an independent predictor of increased mortality in CKD patients. The aim of this study is to analyze the prevalence of PH in patients with CKD, its severity in different stages of CKD, and risk factors for it. One hundred and eight patients with CKD treated at Karnataka Institute of Medical Sciences, Hubli, Karnataka, between January 1, 2014, and June 30, 2015, were selected. Clinical evaluation and relevant investigations including echocardiography were done. Follow-up echocardiography was done at 3 and 6 months and assessed. The mean age of studied population was 43.53 ± 14.63 years. Sex ratio was 2.72:1 (male:female). PH was present in 47 of 108 (43.5%) cases at beginning, 41 of 83 (491.4%) at 3 months, and 32 of 64 (50%) at 6 months. The prevalence and severity of PH increased with progression of CKD stage, although not statistically significant. Heart failure with reduced ejection fraction and heart failure with preserved EF were significantly higher among PH group compared to non-PH group ( P < 0.01). Mean hemoglobin in PH group was significantly lower, compared to non-PH group ( P < 0.01). Mean interdialytic weight gain and central venous pressure were higher among PH group than non-PH group. Higher calcium phosphate product ≥50 was more prevalent in PH group than in non-PH group. The majority of them had moderate PH at the beginning of the study which remained same, despite being on hemodialysis. PH is a common complication in CKD patients with prevalence of 43.5%-50%. Left-sided heart failure, anemia, fluid retention, and increased calcium phosphate product are the risk factors for developing PH., Competing Interests: There are no conflicts of interest.