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The inverse Lindley distribution: A stress-strength reliability model
Vikas Kumar Sharma,Sanjay Kumar Singh,Umesh Singh,Varun Agiwal
Statistics , 2014,
Abstract: In this article, we proposed an inverse Lindley distribution and studied its fundamental properties such as quantiles, mode, stochastic ordering and entropy measure. The proposed distribution is observed to be a heavy-tailed distribution and has a upside-down bathtub shape for its failure rate. Further, we proposed its applicability as a stress-strength reliability model for survival data analysis. The estimation of stress-strength parameters and $R=P[X>Y]$, the stress-strength reliability has been approached by both classical and Bayesian paradigms. Under Bayesian set-up, non-informative (Jeffrey) and informative (gamma) priors are considered under a symmetric (squared error) and a asymmetric (entropy) loss functions, and a Lindley-approximation technique is used for Bayesian computation. The proposed estimators are compared in terms of their mean squared errors through a simulation study. Two real data sets representing survival of Head and Neck cancer patients are fitted using the inverse Lindley distribution and used to estimate the stress-strength parameters and reliability.
EFFECTS OF SALICYLIC ACID ON SEEDLING GROWTH AND NITROGEN METABOLISM IN CUCUMBER (CUCUMIS SATIVUS L.)
Singh Pramod Kumar,Chaturvedi Varun Kumar,Bose Bandana
Journal of Stress Physiology & Biochemistry , 2010,
Abstract: Salicylic acid is involved in the regulation of metabolic activity and defense mechanism in plants under various stress conditions. Present study was conducted to determine the effects of salicylic acid (10 to 500 μM) on seedling growth, development and nitrogen use efficiency in cucumber (Cucumis sativus L.) plants with or without nitrogen nutrient. Salicylic acid increased contents of chlorophyll, total non-structural carbohydrate and total nitrogen, as well as nitrate assimilation through the induction of nitrate reductase (EC 1.6.6.1) activity in isolated cucumber cotyledons. Accumulation of salicylic acid was two-fold higher in cotyledons without nitrate supply in comparison to that with nitrate supply. Further 50 μM of SA induced enhancement in seed germination and growth characteristics. However higher salicylic acid concentrations inhibited above physiological characteristics. Results show that, field application of salicylic acid need optimum physiological concentration (e.g., 50 μM) to increase nitrogen use efficiency particularly during germination and seedling growth.
Assessment of the Self-Perception of Dental Appearance, Its Comparison with Orthodontist’s Assessment and Demand for Treatment in Eastern Nepalese Patients
Varun Pratap Singh,Amita Sharma,Deepak Kumar Roy
Advances in Medicine , 2014, DOI: 10.1155/2014/547625
Abstract: Aims. The aim of this study was to assess the self-perception of dental appearance among Eastern Nepalese patients using aesthetic component (AC) of the index of orthodontic treatment need (IOTN) and to compare it with that of an orthodontist’s assessment using the same scale and determine whether gender, area of residence, and level of education influence subject’s self-perception and orthodontist’s ratings. Methods. A total of 252 subjects (equal number of male and female) were conveniently selected. The average ages of subjects were years. The level of subject’s perception and orthodontist’s assessment was analyzed by nonparametric Chi square test. Kappa coefficient was done to verify its agreement. The Spearman’s correlation test was used to check the association of educational level and age. Mann-Whitney test was used to check the associations of sex and areas of residence. Results. The demand for treatment was significantly associated with the perception of the subject and orthodontist’s assessment. However, age, gender, and educational level were statistically insignificant in influencing subject perception and orthodontist’s assessment. Conclusion. Patient’s self-perception should be given equal importance while planning orthodontic treatment. 1. Introduction A person having an attractive smile is appreciated by everyone. People always want to know how they look and what others think about their physical appearance. Therefore, a pleasing smile and an attractive facial appearance help to improve one’s self-esteem and have a positive impact on building social as well as professional relations. One with poor dental appearance may have a negative impact [1]. Enhancing dentofacial esthetics is one of the primary goals of orthodontic treatment. Frequently, people desire orthodontic treatment to address their esthetics concerns [2, 3]. A number of studies have shown that children have developed a self-perception for the need of orthodontic treatment [3–10]. Orthodontic treatment is determined mostly by the objective assessment. The patient’s perception toward seeking a dental treatment is usually ignored [2, 11]. The index of orthodontic treatment need (IOTN) has two components: one component relates to dental and functional health (dental health component (DHC)) and the other is based on aesthetic impairment of malocclusions (aesthetic component (AC)). The former is concerned only about dental health [12, 13] and the later deals with psychological need for orthodontic treatment [14]. The AC IOTN (Figure 1) consists of ten colorful photos of the
Psychosocial Determinants of Tobacco Use among School Going Adolescents in Delhi, India
Varun Kumar,Richa Talwar,Neelam Roy,Deepak Raut,Saudan Singh
Journal of Addiction , 2014, DOI: 10.1155/2014/170941
Abstract: Background. Tobacco use is one of the major preventable causes of premature death and disease in the world. Many psychosocial factors were found to influence tobacco use. Therefore the present study was designed to determine the role of psychosocial factors associated with tobacco use among school going adolescents in Delhi, India. Methods. Cross-sectional study was conducted from February 2013 to September 2013 in four government schools in South district of Delhi, India. The questionnaire contains questions adapted from GYTS (Global Youth Tobacco Survey) to find the prevalence and pattern of tobacco use among adolescents. Data were analyzed using SPSS version 21. Results. The prevalence of ever and current tobacco use was found in 16.4% and 13.1%. Current smoking and current tobacco chewing were found in 10.2% and 9.4% students, respectively. The risk of current tobacco use was found to be higher among males ( value = 0.000) and in those who got higher pocket money ( value = 0.000). Psychosocial factors like lower general self-efficacy and maladjustments with peers, teachers, and schools were also found to be significant predictors of current tobacco use. Conclusion. The study has revealed higher prevalence of ever and current tobacco use among adolescent students in Delhi, India. 1. Introduction Tobacco use is one of the major preventable causes of premature death and disease in the world [1]. A disproportionate share of the global tobacco burden falls on developing countries, where 84% of 1.3 billion current smokers reside. Nearly 70% of the world’s smokers live in low and middle-income countries [2]. The World Health Organization (WHO) attributes approximately 5 million deaths a year to tobacco. The number is expected to exceed 10 million deaths by 2020, with approximately 70% of these deaths occurring in developing countries [3]. India is the second largest consumer of tobacco in the world. The tobacco situation in India is unique because of a vast spectrum of tobacco products available for smoking as well as smokeless use. The early age of initiation underscores the urgent need to intervene and protect this vulnerable group from falling prey to this addiction. In India alone, nearly 1 in 10 adolescents in the age group 13–15?yr have ever smoked cigarettes and almost half of these report initiating tobacco use before 10?yr of age. Addiction to tobacco and harmful nontobacco products by youth is assuming alarming proportion in India [4]. Recent studies have found that tobacco use is increasing among school children in India and a sizeable
QUALITATIVE EVALUATION OF MARKETED AYURVEDIC RED TOOTH POWDER BY NAMBURI PHASED SPOT TEST
Satadru Palbag,Varun Kumar Singh,Narendra Kumar Singh,D.N.S. Gautam
International Research Journal of Pharmacy , 2013, DOI: 10.7897/2230-8407.04324
Abstract: Simple and precise quality control analysis of consumer goods is the goal of rising FMCG sector. Ayurvedic red tooth powders are one of the most popular FMCG products in today’s market. The main ingredient (≥80%) of these red tooth powders is Swarna gairik (Red Hematite), thus the qualitative evaluation of red tooth powder can be performed by analysis of Swarna gairik. Objective of present study is to develop a simple yet precise method for the quality evaluation of Ayurvedic red tooth powders. Three marketed samples of red tooth powders S-1, S-2 and S-3 were evaluated by Namburi phased spot test against a control sample C. The variation of color and pattern of the spots were carefully evaluated at three distinct time phases. There were marked differences among the color and pattern of the spots for all the three samples when compared with the control, C. Study revealed that S-1 contains standard Swarna gairik whereas S-2 and S-3 contains spurious Swarna gairik. We concluded that the NST is a simple and dependable technique for the evaluation of Ayurvedic red tooth powder.
Memory Effect in Chemotaxis Equation  [PDF]
Bhupendra Singh, Loukrakpam Kennedy Meitei, Ranjit Kumar, Varun Malik, Yogesh Kumar, Nihal Kumar
Journal of Modern Physics (JMP) , 2016, DOI: 10.4236/jmp.2016.710099
Abstract: Diffusion-Reaction (DR) equation has been used to model a large number of phenomena in nature. It may be mentioned that a linear diffusion equation does not exhibit any traveling wave solution. But there are a vast number of phenomena in different branches not only of science but also of social sciences where diffusion plays an important role and the underlying dynamical system exhibits traveling wave features. In contrast to the simple diffusion when the reaction kinetics is combined with diffusion, traveling waves of chemical concentration are found to exist. This can affect a biochemical change, very much faster than straight diffusional processes. This kind of coupling results into a nonlinear (NL) DR equation. In recent years, memory effect in DR equation has been found to play an important role in many branches of science. The effect of memory enters into the dynamics of NL DR equation through its influence on the speed of the travelling wavefront. In the present work, chemotaxis equation with source term is studied in the presence of finite memory and its solution is compared with the corresponding chemotaxis equation without finite memory. Also, a comparison is made between Fisher-Burger equation and chemotaxis equation in the presence of finite memory. We have shown that nonlinear diffusion-reaction-convection equation is equivalent to chemotaxis equation.
Organic-Ruthenium(II) Polypyridyl Complex Based Sensitizer for Dye-Sensitized Solar Cell Applications
Lingamallu Giribabu,Varun Kumar Singh,Challuri Vijay Kumar,Yarasi Soujanya,Veerannagari Gopal Reddy,Paidi Yella Reddy
Advances in OptoElectronics , 2011, DOI: 10.1155/2011/294353
Abstract: A new high molar extinction coefficient organic-ruthenium(II) polypyridyl complex sensitizer (RD-Cou) that contains 2, ,6, -tetramethyl-9-thiophene-2-yl-2,3,5,6,6a,11c-hexahydro1H,4H-11oxa-3a-aza-benzoanthracene-10-one as extended -conjugation of ancillary bipyridine ligand, 4, -dicaboxy-2, , -bipyridine, and a thiocyanate ligand in its molecular structure has been synthesized and completely characterized by CHN, Mass, 1H-NMR, UV-Vis, and fluorescence spectroscopies as well as cyclic voltammetry. The new sensitizer was tested in dye-sensitized solar cells using a durable redox electrolyte and compared its performance to that of standard sensitizer Z-907. 1. Introduction The increasing demand for power supply as well as environmental concern for the consumption of fossil fuel have triggered a greater focus all over the world on renewable energy sources over the past decades [1]. In this context, solar energy appears to be very attractive alternate: covering 0.16% of the earth with 10% efficient solar conversion systems would provide power nearly twice the world’s consumption rate of fossil energy [2]. For this reason, dye-sensitized solar cells (DSSC) have emerged as one of the most promising candidates because of its cost-effective manufacturing, a respectable high efficiency and a remarkable stability under the prolonged thermal and light soaking dual stress among various photovoltaics [3–5]. A typical DSSC system consists of a nanocrystalline semiconductor that adsorbs a sensitizer on its surface, a Pt-counter electrode, and a redox mediator. The photosensitizer plays a crucial role in achieving higher photoconversion efficiency and has been actively studied globally. A wide variety of sensitizers have been studied for DSSC that includes various metal complexes, organic molecules, porphyrins, and phthalocyanines and so forth [6–9]. But only ruthenium-based sensitizers could have marked their way towards commercialization because of their high photoconversion efficiencies. The most successful ruthenium charge transfer sensitizers employed in such cells are bis(tetrabutylammonium)-cis-di(thiocyanato)-N,N′-bis(4-carboxylato-4′-carboxylic acid-2,2′-bipyridine)ruthenium(II) (the N719 dye) and trithiocyanato 4,4′4′′-tricaboxy-2,2′:6′,2′′-terpyridine ruthenium(II) (the black dye) produced solar-energy-to-electricity conversion efficiencies of >11% [10–13]. The high efficiency of these complexes are attributed to its suitable ground- and excited-state energy levels with respect to the nanocrystalline TiO2 conduction band energy and matching redox properties
Neurodegenerative Shielding by Curcumin and Its Derivatives on Brain Lesions Induced by 6-OHDA Model of Parkinson's Disease in Albino Wistar Rats
Shyam Sunder Agrawal,Sumeet Gullaiya,Vishal Dubey,Varun Singh,Ashok Kumar,Ashish Nagar,Poonam Tiwari
Cardiovascular Psychiatry and Neurology , 2012, DOI: 10.1155/2012/942981
Abstract: Study was undertaken to evaluate the neurodegenerative defending potential of curcumin (CUR), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) on 6-hydroxydopamine-(6-OHDA) induced Parkinsonism model in rats. Curcuminoids were administered (60?mg/kg, body weight, per oral) for three weeks followed by unilateral injection of 6-OHDA on 22nd day (10?μg/2?μL) into the right striatum leading to extensive loss of dopaminergic cells. The behavioral observations, biochemical markers, quantification of dopamine (DA), DOPAC, and HVA followed by dopamine (D2) receptor binding assay and tyrosine hydroxylase (TH, using immunohistochemistry) were evaluated using HPLC after three weeks of lesion. Pretreated animals showed significant protection against neuronal degeneration compared to lesion animals by normalizing the deranged levels of biomarkers and showed the potency in the order CUR > DMC > BDMC. The same order of effectiveness was observed in D2 receptors binding assay and TH immunohistochemistry study. We conclude that curcuminoids appear to shield progressive neuronal degeneration from increased oxidative attack in 6-OHDA-lesioned rats through its free radical scavenging mechanism, and DA, DOPAC, and HVA enhancing capabilities in the sequence of efficacy CUR > DMC > BDMC. Further, curcuminoids may have potential utility in treatment of many more oxidative stress-induced neurodegenerative disorders. 1. Introduction Neurodegenerative disorders is a class of neurological diseases marked by extensive neuronal loss in the brain [1]. Progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta region leads to the progression of Parkinson’s disease (PD). This is followed by depletion of striatum dopamine content [2]. When up to 80% of the dopamine-producing cells are damaged, and are not able to produce enough dopamine, then the motor symptoms (bradykinesia, resting tremor, rigidity, and postural disturbances) of PD appear. 6-OHDA, a potent neurotoxin, can severely damage dopaminergic neurons in substantia nigra, leading to a significant decrease in dopamine levels, followed by precise behavioral, biochemical, and pathological changes distinctive in PD. These toxic effects can be attributed to the formation of various reactive oxygen species, lipid peroxidation, depletion of reduced glutathione, and mitochondrial complex I deficits [3]. 6-OHDA-lesioned rat model has a measurable motor deficit, which can be seen by apomorphine-induced contralateral rotations [4]. Although progress has been made in the symptomatic treatment of PD since
Trends of Seroprevalence, Epidemiology and Clinical Presentation of HIV in North India: A Tertiary Care Hospital Based Study  [PDF]
Varun Goel, Dinesh Kumar, Vrushali Patwardhan, Veena Balooni, Shalini Singhal, Sarman Singh
World Journal of AIDS (WJA) , 2016, DOI: 10.4236/wja.2016.62008
Abstract: Introduction: HIV infection represents a major public health problem for both developing and developed countries as it has grown to global pandemic. Spectrum of clinical presentation of HIV can greatly vary with geopolitical, socioeconomic and cultural environment. Aims: The aim of this study was to estimate the prevalence, socio-demographic conditions, clinical presentations, opportunistic infections and the possible associated risk factors for acquiring HIV infection. Materials and Methods: An observational prospective study was conducted from January 2010 to December 2014 at our centre situated in north India. As per the strategy and policy prescribed by NACO, tests were performed on the serum samples. Results: Out of the total 35369 clients tested for HIV infection, 292 were found to be HIV-1 seropositive. Two HIV-2 cases were found among the studied population. The seroprevalence of HIV was found to be 0.83% (294/35369). Mean age of the study group was 30 ± 5.65 (range: 02 - 80) years. Overall positivity rates among attendees were found to be 0.97% (138/14098), 0.96% (35/3610), 0.82% (7/850), 0.78% (22/2810) and 0.65% (92/14001) in the years 2010, 2011, 2012, 2013 and 2014 respectively. Heterosexual route of transmission was the major route of infection in 78.2 % patients. At the time of presentation, it was observed that Tuberculosis (14.9%) was the most common opportunistic infection. Conclusion: The study shows that there is a decreasing trend in the HIV prevalence in North India. However, the number of HIV cases is still significant and suggests the need for focused prevention efforts in high-risk groups.
Deep Rooting In-Situ Expansion of mtDNA Haplogroup R8 in South Asia
Kumarasamy Thangaraj, Amrita Nandan, Vishwas Sharma, Varun Kumar Sharma, Muthukrishnan Eaaswarkhanth, Pradeep Kumar Patra, Sandhya Singh, Sashi Rekha, Monika Dua, Narendra Verma, Alla G. Reddy, Lalji Singh
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0006545
Abstract: Background The phylogeny of the indigenous Indian-specific mitochondrial DNA (mtDNA) haplogroups have been determined and refined in previous reports. Similar to mtDNA superhaplogroups M and N, a profusion of reports are also available for superhaplogroup R. However, there is a dearth of information on South Asian subhaplogroups in particular, including R8. Therefore, we ought to access the genealogy and pre-historic expansion of haplogroup R8 which is considered one of the autochthonous lineages of South Asia. Methodology/Principal Findings Upon screening the mtDNA of 5,836 individuals belonging to 104 distinct ethnic populations of the Indian subcontinent, we found 54 individuals with the HVS-I motif that defines the R8 haplogroup. Complete mtDNA sequencing of these 54 individuals revealed two deep-rooted subclades: R8a and R8b. Furthermore, these subclades split into several fine subclades. An isofrequency contour map detected the highest frequency of R8 in the state of Orissa. Spearman's rank correlation analysis suggests significant correlation of R8 occurrence with geography. Conclusions/Significance The coalescent age of newly-characterized subclades of R8, R8a (15.4±7.2 Kya) and R8b (25.7±10.2 Kya) indicates that the initial maternal colonization of this haplogroup occurred during the middle and upper Paleolithic period, roughly around 40 to 45 Kya. These results signify that the southern part of Orissa currently inhabited by Munda speakers is likely the origin of these autochthonous maternal deep-rooted haplogroups. Our high-resolution study on the genesis of R8 haplogroup provides ample evidence of its deep-rooted ancestry among the Orissa (Austro-Asiatic) tribes.
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