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This study proposes a continuous production inventory model for deteriorating items with time and price-dependent demand under markdown policy for both fresh and deteriorated units. In this model, we have adopted the markdown policy to reduce the inventory and to increase the profit or rate of sale of an article, typically for clearance at the end of the season or to sell off obsolete merchandise at the end of its life. Completely deteriorated items are allowed to carry under markdown. Using the differential equations and under various cost considerations, expressions for total profit function, optimum inventory level and cycle length are obtained. All the expressions are illustrated with the help of a numerical example. Sensitivity analysis is carried out to demonstrate the effect of changing parameter values on the optimal solution of the system. more...

In this paper, an infinite time-horizon inventory model has been developed for deteriorating items assuming the demand rate to be constant for some time and then as a linear function of time. The theoretical expressions are obtained for optimum inventory level and total average cost. The model is illustrated with the help of numerical example. Sensitivity analysis has also been conducted to study the effect of the parameter on optimum policies. more...

The kinetics of oxidation of three aldoses (glucose, mannose and galactose) byN-bromoacetamide (NBA) in the presence of an alkaline solution of RuO4 as catalyst and Hg(OAc)2 as co-catalyst and as a scavenger for bromide have been investigated. The main products of the oxidation are the corresponding aldonic acids. The reaction is zero order with respect to aldose and OH−. First order dependence of the reaction on both NBA and RuO4 at low concentrations shifts to zero order at higher concentrations. Addition of acetamide decreases the reaction rate, while addition of Hg(OAc)2 has the opposite effect. No significant effect of ionic strength was observed. OBr− is postulated as the reactive oxidising species and a mechanism involving co-catalysis by RuO4 and HgII is proposed. more...

A 40-year-old man presented with right hypochondrial and epigastric pain and tenderness. There was no history of jaundice or vomiting. Serum alkaline phosphatase was mildly elevated (170 IU/L). His ultrasound was suggestive of gall bladder worms or stones. MRI revealed curvilinear hypointense structure in the gall bladder (Fig. 1); this suggested the diagnosis of gall bladder ascariasis. Common hepatic and bile ducts were normal. Stool examination revealed ova of Ascaris lumbricoides. The patient was given analgesics and albendazole (400 mg single dose). Three days later, he reported relief of symptoms and passage of worm in the stools. Ultrasound done 4 days later showed no worm in the gall bladder. The adult worm of ascariasis usually resides in the small bowel. It can occasionally migrate into biliary system. Involvement of gall bladder is rare because of the small size of cystic duct [1]. Ultrasound is the usual imaging modality for diagnosing gall bladder ascariasis which demonstrates it as curvilinear echogenic structure [1]. In cases which are inconclusive on sonography, MRI may show curvilinear hypointense structure in the gall bladder lumen, while gall stones typically appear as rounded objects of signal void [2]. MRI also allows simultaneous visualization of common hepatic and common bile ducts. Gall bladder ascariasis is usually treated by surgery and endoscopy. Occasionally, medical therapy may lead to spontaneous passage of worm, as happened in our case. more...