Radioprotective and Antioxidant Activity of Fractionated Extracts of Berries of Hippophae rhamnoides

Rakesh Kumar Sharma,Raman Chawla,Rajesh Arora,Shikha Singh,Ravinder Kumar Sagar,Raj Kumar,Ashok Sharma,Manju L. Gupta,Surender Singh,Jagdish Prasad,Haider A. Khan,Anand Swaroop,A.K. Sinha,A.K. Gupta,R 한국식품영양과학회 2007 Journal of medicinal food Vol.10 No.1

Plants are an abundant source of medicinal compounds, some of which are useful in combating free radical-1002 (flavonoid-poor fraction) of Hippophae rhamnoideswere screened on the basis of their reducing power in the aqueousphase. REC-1001 was selected for further study, since it exhibited 27.38 times higher antioxidant activity than REC-1002.REC-1001 also showed significant (P. .05) membrane protection potential at 50 .g/mL, which was attributed to its abilityto scavenge peroxyl radicals (64.82. 1.25% scavenging within 1,440 min). A significant (P. .05) difference of 67.02% infree radical scavenging activity at 1,000 ng/mL between REC-1001 and vitamin E demonstrated the extract fraction’s worthc-tion. Further, REC-1001 was found to be nontoxic up to 200 mg/kg of body weight. This research suggests that the REC-1001 fraction of H. rhamnoidesextract is a safe and effective antioxidant nutraceutical product.

INTEGRABILITY OF DISTRIBUTIONS IN GCR-LIGHTLIKE SUBMANIFOLDS OF INDEFINITE KAEHLER MANIFOLDS

Kumar, Rakesh,Kumar, Sangeet,Nagaich, Rakesh Kumar Korean Mathematical Society 2012 대한수학회논문집 Vol.27 No.3

In present paper we establish conditions for the integrability of various distributions of GCR-lightlike submanifolds and obtain conditions for the distributions to define totally geodesic foliations in GCR-lightlike submanifolds.

GCR-LIGHTLIKE SUBMANIFOLDS OF A SEMI-RIEMANNIAN PRODUCT MANIFOLD

Kumar, Sangeet,Kumar, Rakesh,Nagaich, Rakesh Kumar Korean Mathematical Society 2014 대한수학회보 Vol.51 No.3

We introduce GCR-lightlike submanifold of a semi-Riemannian product manifold and give an example. We study geodesic GCR-lightlike submanifolds of a semi-Riemannian product manifold and obtain some necessary and sufficient conditions for a GCR-lightlike submanifold to be a GCR-lightlike product. Finally, we discuss minimal GCR-lightlike submanifolds of a semi-Riemannian product manifold.

Oxidative Stress and Antioxidants in Disease and Cancer: A Review

Gupta, Rakesh Kumar,Patel, Amit Kumar,Shah, Niranjan,Choudhary, Arun Kumar,Jha, Uday Kant,Yadav, Uday Chandra,Gupta, Pavan Kumar,Pakuwal, Uttam Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.

GCR-LIGHTLIKE SUBMANIFOLDS OF A SEMI-RIEMANNIAN PRODUCT MANIFOLD

Sangeet Kumar,Rakesh Kumar,Rakesh Kumar Nagaich 대한수학회 2014 대한수학회보 Vol.51 No.3

We introduce GCR-lightlike submanifold of a semi-Riemann- ian product manifold and give an example. We study geodesic GCR- lightlike submanifolds of a semi-Riemannian product manifold and obtain some necessary and sufficient conditions for a GCR-lightlike submanifold to be a GCR-lightlike product. Finally, we discuss minimal GCR-lightlike submanifolds of a semi-Riemannian product manifold.

Magneto-transport Properties of La_(0.80)Sr_(0.20)Mn_(1−x)Cu_xO_3 Thin Films Fabricated by Using Spray Pyrolysis

Pawan Kumar,Rakesh Kumar Dwivedi,Pawan Kumar,Ravikant Prasad,Praveen Kumar Siwach,Hari Krishna Singh 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.1

Thin films of La_(0.80)Sr_(0.20)Mn_(1−x)Cu_xO_3 with x = 0.00, 0.04, 0.08, 0.10, 0.15, and 0.20 were deposited on single-crystal LaAlO_3 (100) (LAO) substrates at 250 ± 10 ℃ by using a nebulized spray pyrolysis technique. Structural, surface, and transport characterizations were done by X-ray diffraction (XRD), atomic force microscopy (AFM) and the standard four probe technique, respectively. XRD patterns revealed the formation of single-phase polycrystalline films with a rhombohedral crystal structure. Cu substitution resulted in a uniform decrease in the metal insulator transition (T_(IM)) temperature up to x = 0.10, followed by a drastic decrease in T_(IM) for x = 0.15. Finally, the metal-insulator transition vanished for higher Cu concentrations (x = 0.20) in the observed temperature range. The variation in T_(IM) with the amount of added Cu is explained on the basis of the double exchange mechanism. Cu substitution has been found to perturb the Mn^(3+)-O-Mn^(4+) network and has a strong influence on T_(IM). The variation in resistivity maxima with temperature for different Cu concentrations showed a systematic trend up to x ∼ 0.10. We also explored the electrical conduction at T > T_(IM) in the framework of small polaron hopping in the adiabatic limit. The activation energy showed a strong dependence on the Cu concentration. The maximum magneto-resistance (MR) up to 10%, was observed for x = 0.15 at low temperatures.

Episodes of prolonged “trance-like state” in an infant with hypothalamic hamartoma

Rakesh Kumar,Jaivinder Yadav,Jitendra Kumar Sahu,Manjul Tripathi,Chirag Ahuja,Devi Dayal 대한소아내분비학회 2019 Annals of Pediatirc Endocrinology & Metabolism Vol.24 No.1

Hypothalamic hamartoma (HH) is one of the most common causes of central precocious puberty (CPP) in first few years of life. It can present with either seizures or CPP, although both manifestations coexist in the majority of the children. Gelastic seizures (GS), or laughing spells, are usually the first type of seizures seen in patients with HH. Although a wide variety of seizure types are known to occur in children with HH, GS are most common and consistent seizure type. The clinical presentation of HH may vary with the size and position of the mass, although large tumours typically present with both CPP and seizures. Although CPP can be managed with medical therapy, seizures can be very difficult to treat, even with multiple antiepileptic drugs. Noninvasive gamma knife surgery has been used with some success for the treatment of refractory epilepsy. We present a case of HH with very early onset seizures and CPP. The patient had an atypical form of seizures described by the parents as a "trance-like state" in which the patient had prolonged episodes of unresponsiveness lasting for hours with normal feedings during the episodes. GS occurred late in the course and were refractory to various combinations of antiepileptic drugs. A brain magnetic resonance imaging showed a large sessile HH (>20 mm). Later in the course of the disease, the patient experienced cognitive and behavioural problems. The patient underwent gamma knife surgery at nearly 5 years of age and experienced a modest response in seizure frequency. This case highlights the presentation of HH as a previously unreported seizure morphology described as a prolonged "trance-like state."

A Survey on Data Aggregation And Clustering Schemes in Underwater Sensor Networks

Rakesh Kumar,NavdeepSingh 보안공학연구지원센터 2014 International Journal of Grid and Distributed Comp Vol.7 No.6

Energy consumption is one of the most challenging constraintsof the design and implementation of the sensor network. Underwater sensor networking is the technology that enables the applications like environment monitoring, underwater exploration, seismic monitoring and other surveillance applications. In underwater sensor network,a sensor node senses the data and transmits it to the sink. Many routing algorithms have been proposed in order to make the network phase of UWSNs more efficient.In this report, we present a review and comparison of various data collection algorithms and clustering schemes, proposed recently in order to execute the demands of the ongoing researches. The main goal of data aggregation technique is to accumulate data in an energy efficient manner for a long-term network monitoring. The main purpose of this study is to present algorithms addressing issues like deployment and localization in UWSNs under different conditions.

The incomplete generalized $\tau$-hypergeometric and second $\tau$-Appell functions

Rakesh Kumar Parmar,Ram Kishore Saxena 대한수학회 2016 대한수학회지 Vol.53 No.2

Motivated mainly by certain interesting recent extensions of the generalized hypergeometric function [\emph{Integral Transforms Spec. Funct.} 23 (2012), 659--683] and the second Appell function [\emph{Appl. Math. Comput.} 219 (2013), 8332--8337] by means of the incomplete Pochhammer symbols $ \left(\lambda; \kappa \right)_{\nu} $ and $ \left[\lambda; \kappa \right]_{\nu}$, we introduce here the family of the incomplete generalized $\tau$-hypergeometric functions $_{2}\gamma_{1}^{\tau}(z) $ and $ _{2}\Gamma_{1}^{\tau}(z) $. The main object of this paper is to study these extensions and investigate their several properties including, for example, their integral representations, derivative formulas, Euler-Beta transform and associated with certain fractional calculus operators. Further, we introduce and investigate the family of incomplete second $\tau$-Appell hypergeometric functions $\Gamma_{2}^{\tau_{1},\tau_{2}}$ and $\gamma_{2}^{\tau_{1},\tau_{2}}$ of two variables. Relevant connections of certain special cases of the main results presented here with some known identities are also pointed out.

Modeling and flow analysis of piezoelectric based micropump with various shapes of microneedle

Rakesh Kumar Haldkar,Vijay Kumar Gupta,Tanuja Sheorey 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.6

Micropumps have been investigated as drug delivery and disease diagnostic devices. Many of these micropumps have been designed,considering primarily, available micro fabrication technologies rather than appropriate pump performance analysis. Piezoelectric andsilicon based micro pumps are more popular as compared to other smart materials being explored. The microneedle is an integral part ofthese micropumps providing an interface between the drug reservoir and the patient’s body for extracting the blood for investigation. Blood collected in the pump chamber passes through the biosensor and gives the required investigation report. It is aimed to minimize thepain while the microneedle is inserted in the body without having any effect on the flow characteristics. Several factors affect the painwhile inserting the needle, out of which shape and size of the microneedle are two important parameters. In this study we have investigatedthe effect of shape of the microneedle on the flow inside the micropump. A micropump design is based on the required flow at thebiosensor point. All computations were carried out with water (Newtonian fluid) as the working fluid after carrying out a comparativeanalysis with human blood (non-Newtonian fluid). For the pentagonal shaped microneedle, the velocity at the top of the microneedle wasminimum, which is beneficial in that fluid should remain in contact with the sensor for longer time.