Donepezil: A review of the recent structural modifications and their impact on anti-Alzheimer activity

Alzheimer disease (AD) is characterized by a low level of acetylcholine, beta-amyloid (Aβ) aggregation and oxidative stress. Donepezil is the core medicine used for the treatment of AD. Various structural modifications of donepezil have been carried out. Benzylpiperidine part of donepezil has been replaced with benzylpyridine, pyridyl methylpiperidine, benzylpiperazine, pyrimidyl piperazine. These derived molecules showed promising activities as anti-Alzheimer agents. Replacement of indanone part by other heterocyclic rings such as pyridine resulted in the formation of compounds which exhibited monoamine oxidase (MAO) as well as acetylcholinesterase (AChE) inhibition. Propargylamine containing derivatives displayed AChE as well as MAO inhibition properties. Attachment of donepezil with natural compounds like ferulic acid, flavonoids, and curcumin showed antioxidant activities in addition to inhibition of the AChE. Benzylpiperidine and benzylpiperazine have also been combined with condensed heterocyclic rings and these compounds displayed promising anti-Alzheimer properties. This review highlights the important structural modifications of donepezil and their influence on biological activities as antiAlzheimer agents

Influence of Heavy and Low Television Watching on Study Habits of Secondary School Students—A Study

The study was undertaken to find out the influence of heavy and low TV watching on study habits of secondary school students. A sample of 500 students was drawn randomly from various Government secondary and higher secondary schools of District Srinagar (J&K). Heavy and low TV viewers were identified on the basis of Q3 and Q1.  Besides, Study Habits Inventory by M.N Palsane and Anuradha Sharma was administered to assess the study habits. The collected data was analyzed by using Mean, Standard Deviation and ‘t’ test. Line graph was plotted in order to make the results transparent. The results revealed a significant difference between the mean scores of heavy and low TV viewers on study habits. Key Words: Heavy and Low TV; Watching; Study Habits; Secondary School Student

Deniable Authentication Protocol using Promised Signcrypion Based on Hyper Elliptic Curve

Anonymity and deniability has an essential role in promising internet environment. Promised signcrypion enable the sender to generate signcryptext with promised property sending it to the receiver. According to the promised property only the intended receiver can verify the original source generating the message. Hyper elliptic curve is considered suitable for constrained devices due to its lesser size key. In this paper we proposed an efficient promised signcrypion scheme based on the hardness of hyper elliptic curve discreet logarithm problem (HECDLP). We compare proposed scheme with existing scheme in term of cost (computational and communication). The proposed scheme reduces computational cost about 87.42% at sender side and 90.56% at receiver side and total communication overhead about 61.45 %. This scheme ensure the security issues like message confidentiality, message integrity, sender anonymity, authenticity

Even Order Ranked Set Sampling with Auxiliary Variable

Even order ranked set sampling (EORSS) is a novel proposed ranked set sampling scheme connected with an auxiliary variable correlated with the study variable. This scheme quantifies only the one sampling unit which is at even position from each ranking set by employing specific criteria. The performance of the ratio estimator under EORSS is compared to its contemporary estimators in simple random sampling (SRS), ranked set sampling (RSS), median ranked set sampling (MRSS) and quartile ranked set sampling (QRSS) exploiting the same number of quantified units. The simulation results proved that EORSS is an efficient alternative sampling scheme for ratio estimation than SRS, RSS, MRSS and QRSS

Caladium cv. Florida sweetheart production at different planting depths and sowing dates

Ornamental bulbous crops emergence and yield can be improved by its emergence from soil. The response of Caladium to different planting depths and dates was investigated at Ornamental Horticulture Nursery, Department of Horticulture, The University of Agriculture, Peshawar during the year 2008. Randomized Complete Block Design in a split plot arrangement was used repeated three times. Sowing dates (30th March, 15th April and 30th April) were allotted to main plots whereas planting depths (2.5 cm, 5 cm, 7.5 cm and 10 cm) were kept in sub plots. Findings revealed that Caladium tubers sown on 30th March took maximum days to sprouting (33), produced maximum number of sprouts plant-1 (2.21), gained maximum tuber size (40.88 cm3) with high tuber yield (5397 kg ha-1). On the other hand, tubers sown on 30th April took less days to sprouting (20.21), produced less number of sprouts plant-1(1.53), produced small tuber (33.28 cm3) and total tuber yields was also less (4374 kg ha-1). In case of planting depth, Caladium tubers sown at a depth of 7.5cm resulted in maximum plant height (52 cm), tuber size (41.76 cm3), and tuber yield (5288 kg ha-1) while maximum number of tubers plant-1 (1.92) was observed at a depth of 10 cm. Tubers sown in 2.5 cm depth resulted in minimum tuber yield (4538 kg ha-1) and plant height (46.56 cm). To maximize vegetative as well as tubers production of Caladium cv. Florida sweet heart, it shall be sown on 30th March with 7.5cm depth

Response of Tuberose (Polianthes tuberosa) to Potassium and Planting Depth

A research work was carried to find out the effect of planting depths, potassium levels and their interaction during the year 2012. The corms of tuberose were planted at a depth of 5, 10, and 15 cm and were fertilized with four levels of potassium 0, 50, 100 and 150 Kg of K2O per hectare using K2SO4 as a source of K2O. Result of the study revealed that planting depth of 15 cm significantly increased length of spike (56.9 cm), number of florets spike-1 (54.84), and plant height (103.13) cm. Planting depth of 5cm cause decreased number of days to last floret opening (180.08). Potassium level of 150 kg of K2O ha-1 length of spike (55.24 cm), number of florets spike-1 (49.2) and plant height (100.29 cm). Planting depth of 15 cm and fertilizer application of 150 kg of K2O ha-1proved to be superior regarding length of spike opening (64.4cm), number of florets spike-1 (62.2) and plant height (106.20 cm). Hence planting tuberose at a depth of 15cm and fertilizer application of 150 kg of K2O ha-1 is recommended for commercial cultivation of tuberose. Keywords: Tuberose; Potassium; Planting Depth; Number of Florets Spike-1; Spike Length

A comparative study of DC servo motor parameter estimation using various techniques

A lot of research is being carried out on the Direct Current (DC) servo motor systems due to their excessive applications in various industrial sectors owing to their superior control performance. Parameters of the DC servo motor systems to be used in the simulation software are usually unknown or change with time and have to be determined accurately for obtaining the precise simulation response. In this paper, three different estimation techniques for multi-domain DC servo motor model parameters are discussed namely the Compare Coefficient Method, MATLAB Parameter Estimation Toolbox, and System Identification Toolbox. The paper performs a comparison of these methods to identify the one that gives the most accurate results. Experimental data has been used for the comparison of the estimated response from the techniques. The results show that the parameters obtained from the parameter estimation method give the most accurate simulation results with the least error against the experimental results. The study is significant for guiding researchers to prefer this method for estimation purposes of DC servo motor simulation model parameters. The presented technique, i.e. parameter estimation technique, is relatively less complex and requires less computational cost as compared to other techniques found in the literature