Improving Performance of Quantum Heat Engines by Free Evolution

The efficiency of a quantum heat engine is maximum when the unitary strokes are adiabatic. On the other hand, this may not be always possible due to small energy gaps in the system, especially at the critical point where the gap vanishes. With the aim to achieve this adiabaticity, we modify one of the unitary strokes of the cycle by allowing the system to evolve freely with a particular Hamiltonian till a time so that the system reaches a less excited state. This will help in increasing the magnitude of the heat absorbed from the hot bath so that the work output and efficiency of the engine can be increased. We demonstrate this method using an integrable model and a non- integrable model as the working medium. In the case of a two spin system, the optimal value for the time till which the system needs to be freely evolved is calculated analytically in the adiabatic limit. The results show that implementing this modified stroke significantly improves the work output and efficiency of the engine, especially when it crosses the critical point.Comment: 8 pages, 8 figure

Universal finite-time thermodynamics of many-body quantum machines from Kibble-Zurek scaling

We demonstrate the existence of universal features in the finite-time thermodynamics of quantum machines by considering a many-body quantum Otto cycle in which the working medium is driven across quantum critical points during the unitary strokes. Specifically, we consider a quantum engine powered by dissipative energizing and relaxing baths. We show that under very generic conditions, the output work is governed by the Kibble-Zurek mechanism, i.e., it exhibits a universal power-law scaling with the driving speed through the critical points. We also optimize the finite-time thermodynamics as a function of the driving speed. The maximum power and the corresponding efficiency take a universal form, and are reached for an optimal speed that is governed by the critical exponents. We exemplify our results by considering a transverse-field Ising spin chain as the working medium. For this model, we also show how the efficiency and power vary as the engine becomes critical.Comment: 11 pages, 7 figure

Deep Learning

Deep Learning was developed as a Machine learning approach to influence advanced input-output mappings. It had been for learning concerning multiple levels of illustration and abstraction to create sense of the information such as images, text and sound. Deep learning excels at distinguish patterns in unstructured information, that most of the people grasp as media like images, sound, video and text

PORPHYSOMES-A PARADIGM SHIFT IN TARGETED DRUG DELIVERY

A novel drug delivery system is the one that ensures optimum dose at the right time, at the right location. Porphysomes are among those drug delivery systems. Porphysomes are a means of vesicular drug delivery systems. They are liposome-like structures composed completely of porphyrin lipid. The porphysomes encapsulates the active medicament in vesicular structure. They are having an aqueous core which can be loaded with the medicament. They have the capacity to destroy the disease tissues. They absorb the heat in the near infrared region and release this heat to destroy the diseased tissues. Porphysomes are having immense applications in the field of positron-electron therapy (PET), photoacoustic imaging, photothermal therapy etc. This review article discusses regarding the Porphysome-the drug delivery system, its advantages and disadvantages, composition, method of preparation, applications and various aspects related to the porphysomal drug delivery

FORMULATION AND EVALUATION OF LORAZEPAM ENCAPSULATED COLLAGEN/PECTIN BUCCAL PATCH

Objective: To formulate and characterize Lorazepam loaded buccal patches using mucoadhesive, biodegradable, natural polymers-pectin (hydrophilic) and collagen (lipophilic) for treating epileptic seizures. Methods: Lorazepam loaded buccal patches were prepared by solvent casting method and were subjected to various Physico-chemical evaluation parameters to find the optimized buccal patch. The in vitro drug release study and ex vivo permeation study was carried out. The stability study and histopathological study of optimized Lorazepam loaded buccal patch was also carried out. Results: From in vitro drug release study, it was found that Lorazepam loaded buccal patch (B4) exhibited maximum drug release of 96.16 %±0.07 than other formulations at the end of 4 h, indicating an initial burst release followed by sustained release with release kinetics as Higuchi diffusion model. Based on the in vitro drug release, % drug content, % swelling index, folding endurance, B4 formulation was considered as optimised formulation and was further characterized. Ex vivo permeation study revealed that the cumulative amount of drug permeated from optimised Lorazepam loaded buccal patch (B4) was higher (3831.4±0.21µg/cm2) than marketed Midazolam buccal solution (1724±0.12 µg/cm2) and control drug solution (895.42±0.07 µg/cm2) with an enhancement ratio of 4.8. B4 formulation also showed a higher flux value (12.52±0.02µg/cm2/hr) compared to marketed formulation (5.732±0.01 µg/cm2) and control drug solution (2.563±0.03 µg/cm2) of P<0.05. The histopathological study using bovine buccal mucosa revealed that the B4 formulation is safe for buccal application. The stability study confirmed that B4 formulation is stable in both room and refrigeration conditions. Hence the formulated Lorazepam loaded buccal patch seems to be a promising carrier for the enhanced buccal delivery of Lorazepam in treating epileptic seizures. Conclusion: The formulated Lorazepam loaded collagen/pectin buccal patch was found to be an efficient and stable route for the buccal delivery of Lorazepam in treating acute epileptic seizures which could be further explored scientifically

CRYPTOSOMES: A REVOLUTIONARY BREAKTHROUGH IN NOVEL DRUG DELIVERY

The vesicular drug delivery systems are promising approaches to overthrown the problems of drugs having lesser bioavailability and rapid elimination from the body. The four type of lipid based drug delivery systems are: solid-lipid particulate system, emulsion based system, solid lipid tablet and vesicular system. Cryptosomes, a novel emerging vesicular drug delivery system which can overcome the disadvantages associated with conventional drug delivery systems like high stability, increased bioavailability, sustained release, decreased elimination of rapidly metabolizable drugs etc. The word Cryptosome was orginated from Greek word ‘’Crypto’’ means hidden and ‘’Soma’’ means body. It is formed from the mixture of phospholipids like distearoyl phosphatidyl ethanolamine-polyethylene glycol (DSPE-PEG) with distearoylphosphatidylcholine. These entire information regarding its origin and formation is explained in Dinesh Kumar et al. Vesicular systems symbolizes the use of vesicles in the different fields as carrier system or additives. This review disclose various vesicular drug delivery system and point out the advancement of cryptosome in the world of drug delivery. This review would help researchers involved in the field of vesicular drug delivery

Lidar Observations of aerosol layers just below the tropopause level during IFP-INDOEX

A lidar system has been used at Gadanki (13.5º, 79.2ºE) to study the characteristics of aerosol layer (cloud) occurring just below the tropical tropopause. The preliminary results of the lidar observations indicate that the cloud occurs ~ 2 km below the tropopause. The top and bottom edges of the cloud have propensity for ice crystal presence with liquid droplets/ vapours in-between. The clouds show temporal fluctuations (in their backscattering ratio) with temporal scales of the order of 30–90 min

Biocompatibility studies on lanthanum oxide nanoparticles

Lanthanum oxide nanoparticles (LONP), a rare earth metal oxide, have unique properties that make them a suitable candidate for several biomedical applications. We investigated certain key in vitro and in vivo biocompatibility endpoints on LONP. LONP were cytotoxic in in vitro assays and predominantly exerted their action via release of reactive oxygen species. These nanoparticles were neither irritants nor sensitizers in a rabbit model. LONP extracts did not exert any acute systemic toxicity effects in mice. On the other hand LONP exerted toxicity to the liver following oral administration, suggesting that these particles are absorbed from the gastrointestinal (GI) tract and deposited in the hepatobiliary system. LONP did not induce any mutation in the Ames test both in the presence or absence of S-9. These observations provide a base line biocompatibility and toxicity data on LONP. The current findings will also be useful in defining standards for nanoparticle containing devices. © The Royal Society of Chemistry