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2.
Sci Rep ; 14(1): 3261, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38331946

ABSTRACT

This paper proposes an innovative approach for improving the charging efficiency of electric vehicles (EVs) by combining photovoltaic (PV) systems with AC-DC Power Factor Correction (PFC). The proposed approach employs bi-directional power flow management within the PFC system, allowing for enhanced resource utilization and EV battery capacity under a variety of environmental circumstances. A modified Lyapunov-based robust model reference adaptive controller (M-LRMRAC) is developed to provide real-time Maximum Power Point Tracking (MPPT) for the PV array. By quickly recording the MPP, this controller skilfully adjusts to shifting radiation and temperature dynamics. A noteworthy accomplishment is that the M-LRMRAC outperforms traditional Perturb and Observe (P&O) techniques by achieving quick MPP convergence (0.54 s). Additionally, the benefits of this integrated system go beyond effective MPPT. The method achieves operating at unity power factor and reduces total harmonic distortion, which results in improved power quality when charging EV Batteries (EVB). The entire solution provided by this multifaceted architecture improves the quality of electricity delivered to EV batteries while also increasing energy efficiency. This research helps to the evolution of sustainable and dependable EV charging infrastructure by solving difficulties and optimising performance. The combination of PV systems with AC-DC PFC, aided by the M-LRMRAC technology, presents a viable route for attaining efficient, clean, and high-quality EV charging, hence supporting the shift to a greener and more sustainable transportation landscape.

3.
ISA Trans ; 145: 298-314, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38057173

ABSTRACT

This paper addresses the optimal tracking control problem of an Autonomous Underwater Vehicle (AUV) using Pontryagin's Minimum Principle (PMP). The formulation uses a choice of Hamiltonian function using the desired control objective with AUV dynamics acting as dynamic constraints. We first develop PMP based on AUV kinematics and then extend it to the dynamics to arrive at optimal thrusts and moments. Necessary conditions for optimality are derived for both the models using PMP, which results in optimal trajectories that simultaneously minimize the tracking error as well as the control cost, thereby arriving at energy optimality. It was observed that the adjoint variables (costates) are indeed the momenta in the inertial and body-fixed frames. At the kinematic level, this forms a stable solution. The developed methodology is applied to both 2D and 3D AUV model with disturbances due to inputs and ocean currents. Numerical simulations are carried out with the derived control laws for a given trajectory tracking target. Quantitative evaluation of the performance and comparison of the controller is done using Mean Square Error(MSE) and Total Variation(TV) measures. The proposed control laws are found to achieve the desired control objectives.

4.
J Oral Maxillofac Pathol ; 25(2): 370, 2021.
Article in English | MEDLINE | ID: mdl-34703139

ABSTRACT

There are a number of guidelines to assess the nutrition status of cancer cases. None of these guidelines are specifically head and neck cancer related; except for the European guidelines. This article reviews the different guidelines in nutrition for cancer cases and also their drawbacks.

5.
J Pharm Bioallied Sci ; 6(2): 81-5, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24741274

ABSTRACT

Phospholipids of erythrocyte are found as bilayer with choline containing phospholipid like phosphatidyl choline and sphingomylein in the outer layer and amine containing phospholipid like phosphatidyl ethanolamine and phosphatidyl serine in the inner layer. This arrangement is known as phospholipid asymmetry. Lipid asymmetry is maintained throughout the entire life span of red blood cell and is disturbed when cells enter into the stage of apoptosis. We here discuss some of the conditions in which phospholipid asymmetry of erythrocyte is maintained and disturbed and the various detection methods to check the distortion phospholipid asymmetry of it.

6.
Anc Sci Life ; 33(4): 222-8, 2014.
Article in English | MEDLINE | ID: mdl-25593402

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the anti-diabetic activity of ethanol extract of Tabernamontana divaricata (L.) and its ameliorative effect on oxidative stress in alloxan-induced diabetic rats. MATERIALS AND METHODS: Diabetes was induced by single intraperitoneal injection of alloxan monohydrate (140 mg/kg body weight). Methanol extract of T. divaricata was administered at the doses of 100 and 200 mg/kg body weight in diabetic induced rats including glibenclamide (3 mg/kg) as a reference drug. In the continuous 21 days treatment, fasting blood glucose level was determined on 0, 7, 14 and 21 days. On day 21, serum lipid profiles and glycosylated hemoglobin, liver antioxidant enzymes levels were estimated. RESULTS: Experimental findings showed a significant anti-diabetic potential of the extract in terms of reduction in blood glucose levels and a correct effect on the altered biochemical parameters. Observed data were found statistically significant in correction of antioxidant enzyme level accompanied with diabetes, particularly at the dose of 200 mg/kg body weight. CONCLUSION: Based on the results, it can be concluded that the T. divaricata is found to be effective in type 2 diabetes in rats and to have an ameliorative effect on the associated oxidative stress.

7.
J Nat Sci Biol Med ; 4(1): 207-12, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23633864

ABSTRACT

The present study was conducted to assess the effect of fenugreek, insulin and glimepiride alone and their combination in diabetic rat liver. Fifty six male Sprague dawley rats of uniform age were randomly divided into seven groups. Group 1: Non-diabetic control; Group 2: Streptozotocin (40 mg/Kg i/p single dose)-induced diabetic control; Group 3: Insulin (4 U/kg once daily for 8 weeks) treatment in diabetic rats; Group 4: Glimepiride (4 mg/Kg orally once daily for 8 weeks) treatment in diabetic rats; Group 5: Fenugreek seed powder treatment (1 g/kg orally once daily for 8 weeks) in diabetic rats; Group 6: Insulin + Fenugreek seed powder treatment (once daily for 8 weeks) in diabetic rats; Group 7: Glimepiride + Fenugreek seed powder treatment (once daily for 8 weeks) in diabetic rats. Livers were collected at the end of experiment for histopathology and estimation of reduced glutathione (GSH), thiobarbituric acid reacting substances (TBARS), protein carbonyls, glutathione S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PD), Na(+)/K(+) ATPase and Mg(2)+ ATPase, cytochrome P450 (CYP) and glycogen. There was an increase in the concentration of TBARS and protein carbonyls, and decrease in the concentration of GSH and glycogen, and the activity of GST, G6PD, Na(+)/K(+) ATPase and Mg(2)+ ATPase in diabetic livers, while treatment groups showed significant (P < 0.05) increase in the above parameters. The histology of liver revealed marked changes in diabetic rats and mild changes in combination treatment groups. The treatment with fenugreek, insulin and glimepiride improved the liver parameters in diabetic rats and their combination showed a beneficial effect on liver.

8.
Toxicol Int ; 17(2): 64-6, 2010 Jul.
Article in English | MEDLINE | ID: mdl-21170247

ABSTRACT

Experimental study was conducted to evaluate the hepato- and renoprotective effect of silymarin and Terminalia chebula against experimentally-induced acetaminophen (APAP) toxicity in rats. Oral administration of APAP @ 500 mg/kg for 1 to 3 days to all the four groups (six rats in each) resulted in significant elevation of serum triglycerides, total cholesterol, blood urea nitrogen, serum creatinine, and aspartate transaminase activity. Post-treatment with silymarin @ 25 mg/kg and T. chebula 125 mg/kg in groups 2 and 3 and their combination to group 4 from day 4 to 14 has significantly reversed the alterations of above said markers and offered better protection. The results of the study enunciated that silymarin and T. chebula exhibit good hepato- and nephro-protection against APAP toxicity.

9.
Food Chem ; 110(2): 328-33, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-26049223

ABSTRACT

Polyphenol oxidase (PPO) of Barbados cherry was extracted and purified through ammonium sulfate precipitation, gel filtration, and affinity chromatography. The purification factor for PPO was 60% with 8.3% yield. The enzyme was characterized for thermal stability, pH and kinetic parameters. The molecular mass of PPO was approximately the sum of 52 and 38kDa estimated by SDS-PAGE. The purity was checked by native PAGE, showing a single prominent band. The optimum pH was 7.2. The enzyme had a temperature optimum at 40°C and was relatively stable at 60°C, with 55% loss of activity. Sodium diethyl dithiocarbamate (SDDC), l-cysteine and ascorbate significantly inhibited PPO activity. 4-Methyl catechol and catechol were found to be efficient diphenolic substrates for cherry PPO, considering the Vmax/Km ratio. The data obtained in this study may help to understand cherry fruit browning.

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