ABSTRACT
We propose a quantum Stirling heat engine with an ensemble of harmonic oscillators as the working medium. We show that the efficiency of the harmonic oscillator quantum Stirling heat engine (HO-QSHE) at a given frequency can be maximized at a specific ratio of the temperatures of the thermal reservoirs. In the low-temperature or equivalently high-frequency limit of the harmonic oscillators, the efficiency of the HO-QSHE approaches the Carnot efficiency. Further, we analyze a quantum Stirling heat engine with an ensemble of particle-in-a-box quantum systems as the working medium. Here both work and efficiency can be maximized at a specific ratio of temperatures of the thermal reservoirs. These studies will enable us to operate the quantum Stirling heat engines at its optimal performance. The theoretical study of the HO-QSHE would provide impetus for its experimental realization, as most real systems can be approximated as harmonic oscillators for small displacements near equilibrium.
ABSTRACT
The aim of the study was to establish the importance of KOH mount in rapid diagnosis of fungal corneal ulcers. Corneal scrapings were collected from 50 patients with corneal ulcers where clinical features suggested fungal aetiology and ulcers showed no signs of healing on initial treatment. Corneal scrapings were subjected to wet mount with 10% KOH, Gram's stain, and culture on SDA media. Wet mount showed fungal elements in 34 cases (68%) and were classified according to morphology. Gram's stain of corneal scrapings did not provide much help. Fungal culture was positive in 9 (26.4%) out of 34 cases. Specific antifungal treatment was instituted in all cases that showed positive wet mount without waiting for culture reports and on follow-up all these 34 patients showed improvement. Thus wet mount with 10% KOH can be relied upon as the singlemost important screening tool for rapid diagnosis of fungal corneal ulcer and treatment should be dispensed on its basis.
