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      • Data Protection in Clouds using Two Stage Encryption

        Pallav Sharma,Varsha Sharma,Sanjeev Sharma,Jitendra Agrawal 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.4

        Cloud Computing has been an emergent technology that has opened the space for virtualization, as it provides many computational services and storage services over the Internet with the help of a browser. Cloud computing’s core comprises of services like platform, infrastructure and software as a service. The unpredicted boom in cloud computing is driven by its simple economic benefit. It helps in reducing capital expenses and minimizes operating expenses. This move however, has increased a major concern about the protection of data, as against the traditional system the data is now stored online and is far easily exposed than we realize. This raises a major security issue for data protection. Many techniques for protection of data have been proposed so far. However, the best available option till date is to encrypt user data before storing it over the cloud environment and decrypting it again before handing the data back to the cloud user. In this paper, we introduce a more efficient and stronger encryption process that allows a cloud service provider to protect user data more efficiently.

      • KCI등재

        MEAN SQUARE STABILITY IN A MODIFIED LESLIE-GOWER AND HOLLING-TYPE II PREDATOR-PREY MODEL

        Pallav Jyoti Pal,Sahabuddin Sarwardi,Tapan Saha,Prashanta Kumar Mandal 한국전산응용수학회 2011 Journal of applied mathematics & informatics Vol.29 No.3

        Of concern in the paper is a Holling-Tanner predator-prey model with modified version of the Leslie-Gower functional response. Dynamical behaviours such as stability, permanence and Hopf bifurcation have been carried out deterministically. Using the normal form theory and center manifold theorem, the explicit formulae determining the stability and direction of Hopf bifurcation have been derived. The deterministic model is extended to a stochastic one by perturbing the growth equation of prey and predator by white and colored noises and finally the mean square stability of the stochastic model systems is investigated analytically. An extensive quantitative analysis has been performed based on numerical computation so as to validate the applicability of the proposed mathematical model.

      • KCI등재

        Grey Wolf Optimizer Based PID Controller for Speed Control of BLDC Motor

        Dutta Pallav,Nayak Santanu Kumar 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.2

        A BLDC motor is superior to a brushed DC motor, as it replaces the mechanical commutation unit with an electronic one; hence improving the dynamic characteristics, effi ciency and reducing the noise level marginally. Maximum BLDC motor drives use PID controller to control the speed of the machine; because it is simple in structure, relatively cheaper and exhibits good performance. But the main problem associated with PID controller is adjusting its parameters during implementation. In recent works, it has been observed that Particle Swarm Optimization (PSO) technique showed good performance in tuning PID controller. For this purpose, in this article, “Grey Wolf Optimization” (GWO) algorithm is introduced; which is used to optimally tune the PID controller parameters. The objective of this article is to compare the results obtained for tuning of PID controller based on of GWO and PSO technique and a conclusion has been derived that the proposed approach yields superior dynamic performance for BLDC motor.

      • KCI등재

        MEAN SQUARE STABILITY IN A MODIFIED LESLIE-GOWER AND HOLLING-TYPE II PREDATOR-PREY MODEL

        Pal, Pallav Jyoti,Sarwardi, Sahabuddin,Saha, Tapan,Mandal, Prashanta Kumar The Korean Society of Computational and Applied Ma 2011 Journal of applied mathematics & informatics Vol.29 No.3

        Of concern in the paper is a Holling-Tanner predator-prey model with modified version of the Leslie-Gower functional response. Dynamical behaviours such as stability, permanence and Hopf bifurcation have been carried out deterministically. Using the normal form theory and center manifold theorem, the explicit formulae determining the stability and direction of Hopf bifurcation have been derived. The deterministic model is extended to a stochastic one by perturbing the growth equation of prey and predator by white and colored noises and finally the mean square stability of the stochastic model systems is investigated analytically. An extensive quantitative analysis has been performed based on numerical computation so as to validate the applicability of the proposed mathematical model.

      • KCI등재

        Microtubular Dysfunction and Male Infertility

        Sezgin Gunes,Pallav Sengupta,Ralf Henkel,Aabed Alguraigar,Mariana Marques Sinigaglia,Malik Kayal,Ahmad Joumah,Ashok Agarwal 대한남성과학회 2020 The World Journal of Men's Health Vol.38 No.1

        Microtubules are the prime component of the cytoskeleton along with microfilaments. Being vital for organelle transport and cellular divisions during spermatogenesis and sperm motility process, microtubules ascertain functional capacity of sperm. Also, microtubule based structures such as axoneme and manchette are crucial for sperm head and tail formation. This review (a) presents a concise, yet detailed structural overview of the microtubules, (b) analyses the role of microtubule structures in various male reproductive functions, and (c) presents the association of microtubular dysfunctions with male infertility. Considering the immense importance of microtubule structures in the formation and maintenance of physiological functions of sperm cells, this review serves as a scientific trigger in stimulating further male infertility research in this direction.

      • KCI등재

        Coenzyme Q10, oxidative stress markers, and sperm DNA damage in men with idiopathic oligoasthenoteratospermia

        Ahmed T Alahmar,Pallav Sengupta,Sulagna Dutta,Aldo E. Calogero 대한생식의학회 2021 Clinical and Experimental Reproductive Medicine Vol.48 No.2

        Objective: Oxidative stress (OS) plays a key role in the etiology of unexplained male infertility. Coenzyme Q10 (CoQ10) is a potent antioxidant that may improve semen quality and OS in infertile men with idiopathic oligoasthenoteratospermia (OAT), but the underlying mechanism is unknown. Therefore, the present study was undertaken to investigate the effect of CoQ10 on OS markers and sperm DNA damage in infertile patients with idiopathic OAT. Methods: This prospective controlled study included 50 patients with idiopathic OAT and 50 fertile men who served as controls. All patients underwent a comprehensive medical assessment. Patients and controls received 200 mg of oral CoQ10 once daily for 3 months. Semen and blood were collected and analyzed for sperm parameters, seminal CoQ10 levels, reactive oxygen species (ROS) levels, total antioxidant capacity, catalase, sperm DNA fragmentation (SDF), and serum hormonal profile. Results: The administration of CoQ10 to patients with idiopathic OAT significantly improved sperm quality and seminal antioxidant status and significantly reduced total ROS and SDF levels compared to pre-treatment values. Conclusion: CoQ10, at a dose of 200 mg/day for 3 months, may be a potential therapy for infertile patients with idiopathic OAT, as it improved sperm parameters and reduced OS and SDF in these patients.

      • KCI등재

        Coenzyme Q10 Improves Sperm Parameters, Oxidative Stress Markers and Sperm DNA Fragmentation in Infertile Patients with Idiopathic Oligoasthenozoospermia

        Alahmar Ahmed T.,Calogero Aldo E.,Sengupta Pallav,Dutta Sulagna 대한남성과학회 2021 The World Journal of Men's Health Vol.39 No.2

        Purpose: Oxidative stress and sperm DNA fragmentation (SDF) are potential contributing factors for idiopathic male infertility. Coenzyme Q10 (CoQ10) have been reported to be effective in the treatment of idiopathic male infertility, in general, owing to its antioxidant properties. Thus, the present study intends to investigate the effects of CoQ10 therapy on semen parameters, oxidative stress markers and SDF in infertile men, specifically with idiopathic oligoasthenozoospermia (OA). Materials and Methods: In this case-control study, sixty-five infertile patients with idiopathic OA and forty fertile men (control) were included. All participants underwent semen analysis based on the World Health Organization guidelines (5th edition, 2010). Patients received CoQ10 at the dose of 200 mg/d orally for three months. Seminal plasma CoQ10, total antioxidant capacity (TAC), total reactive oxygen species (ROS), glutathione peroxidase (GPx), and SDF levels were measured in controls (baseline) and infertile patients pre- and post-CoQ10 treatment. Results: CoQ10 treatment for three months significantly improved sperm concentration (p<0.05), progressive motility (p<0.05), total motility (p<0.01), seminal fluid CoQ10 concentration (p<0.001), TAC (p<0.001), and GPx (p<0.001) levels in infertile men with OA. Further, ROS level (p<0.05) and SDF percentage (p<0.001) were reduced in OA patients as compared to the baseline. CoQ10 levels also correlated positively with sperm concentration (r=0.48, p=0.01) and total motility (r=0.59, p=0.003) while a negative correlation was recorded between SDF and sperm motility (r=-0.54, p=0.006). Conclusions: CoQ10 supplementation for three months could improve semen parameters, oxidative stress markers and reduce SDF in infertile men with idiopathic OA.

      • KCI등재

        Coenzyme Q10, oxidative stress, and male infertility: A review

        Ahmed T. Alahmar,Aldo E. Calogero,Rajender Singh,Rossella Cannarella,Pallav Sengupta,Sulagna Dutta 대한생식의학회 2021 Clinical and Experimental Reproductive Medicine Vol.48 No.2

        Male infertility has a complex etiopathology, which mostly remains elusive. Although research has claimed that oxidative stress (OS) is the most likely underlying mechanism of idiopathic male infertility, the specific treatment of OS-mediated male infertility requires further investigation. Coenzyme Q10 (CoQ10), a vitamin-like substance, has been found in measurable levels in human semen. It exhibits essential metabolic and antioxidant functions, as well as playing a vital role in mitochondrial bioenergetics. Thus, CoQ10 may be a key player in the maintenance of biological redox balance. CoQ10 concentrations in seminal plasma directly correlate with semen parameters, especially sperm count and sperm motility. Seminal CoQ10 concentrations have been shown to be altered in various male infertility states, such as varicocele, asthenozoospermia, and medical or surgical regimens used to treat male infertility. These observations imply that CoQ10 plays an important physiological role in the maintenance and amelioration of semen quality. The present article thereby aimed to review the possible mechanisms through which CoQ10 plays a role in the regulation of male reproductive function, and to concisely discuss its efficacy as an ameliorative agent in restoring semen parameters in male infertility, as well as its impact on OS markers, sperm DNA fragmentation, pregnancy, and assisted reproductive technology outcomes.

      • KCI등재

        Electrophysiology of Human Gametes: A Systematic Review

        Darbandi Sara,Darbandi Mahsa,Khorram Khorshid Hamid Reza,Sengupta Pallav 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.3

        Purpose: Oocytes and spermatozoa are electrogenic cells with the ability to respond to electrical stimuli and modulate their electrical properties accordingly. Determination of the ionic events during the gamete maturation helps to design suitable culture media for gametes in assisted reproductive technology (ART). The present systematic review focuses on the electrophysiology of human gametes during different stages of maturation and also during fertilization. Materials and Methods: The reports published in the English language between January 2000 and July 2021 were extracted from various electronic scientific databases following the PRISMA checklist using specific MeSH keywords. Results: Subsequent to the screening process with defined inclusion and exclusion criteria, 60 articles have been included in this review. Among them, 11 articles were directly related to the electrophysiology of human oocytes and 49 physiology department to the electrophysiology of human spermatozoa. Conclusions: Gametes generate electrical currents by ionic exchange, particularly Na+, K+, Cl-, H+, Zn2+, Cu2+, Se2+, Mg2+, HCO3 -, and Ca2+ through specific ion channels in different stages of gamete maturation. The ionic concentrations, pH, and other physicochemical variables are modulated during the gametogenesis, maturation, activation, and the fertilization process following gamete function and metabolism. The electrical properties of human gametes change during different stages of maturation. Although it is demonstrated that the electrical properties are significant regulators of cell signaling and are fundamental to gamete maturation and fertilization, their exact roles in these processes are still poorly understood. Further research is required to unveil the intricate electrophysiological processes of human gamete maturation.

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