Guru Gobind Singh Indraprastha University is a public, professional university located in Delhi, India. Founded in 1998 it is a teaching-cum-affiliating university which affiliates 84 colleges in Delhi-NCR and has 15 schools and centres. The university has been graded 'A' by NAAC.GGSIPU is considered as one of the fastest growing universities in north India, and it is consistently ranked amongst the best universities in India which have been established in the past twenty years. A handful of colleges affiliated to GGSIPU feature in the list of best engineering colleges in India.Guru Gobind Singh Indraprastha University has received the Platinum Technology Award for quality and excellence in the field of education, in Geneva, Switzerland, presented by Otherways Management and Consulting , a Paris-based international organisation.Guru Gobind Singh Indraprastha University is a member of the Association of Commonwealth Universities, Association of Indian Universities, Medical Council of India and Distance Education Council. Wikipedia.
Mohapatra S.,Guru Gobind Singh Indraprastha University
Journal of Alloys and Compounds | Year: 2014
Silver (Ag) nanoclusters embedded in soda lime glass were synthesized by Ag ion exchange followed by thermal annealing. The effects of annealing temperature, time and atmosphere on the plasmonic response, structural and optical properties of silver-glass nanocomposites have been investigated using UV-visible absorption spectroscopy and X-ray photoelectron spectroscopy (XPS). As exchanged sample exhibits surface plasmon resonance (SPR) band around 420 nm which showed regular red shift with increase in annealing temperature. A significant red shift of 176 nm (from 420 to 596 nm) and broadening of the SPR peak was observed for annealing in air at 450 C. XPS studies on air annealed samples confirmed the presence of Ag2O in addition to Ag. Subsequent annealing at 250 C in reducing atmosphere resulted in increase in intensity, narrowing and blue shift of the SPR peak to 398 nm. Our observations suggest that SPR tunability is mainly due to the formation and dissolution of Ag 2O nanoshells around Ag nanoclusters in the near-surface region of glass during annealing in oxidizing and reducing atmosphere, respectively. © 2014 Elsevier B.V. All rights reserved.
Dhikav V.,All India Institute of Medical Sciences |
Anand K.,Guru Gobind Singh Indraprastha University
Drugs and Aging | Year: 2011
The hippocampus is a vulnerable and plastic brain structure that is damaged by a variety of stimuli, e.g. hypoxia, hypoperfusion, hypoglycaemia, stress and seizures. Alzheimers disease is a common and important disorder in which hippocampal atrophy is reported. Indeed, the available evidence suggests that hippocampal atrophy is the starting point of the pathogenesis of Alzheimers disease and a significant number of patients with hippocampal atrophy will develop Alzheimers disease. Studies indicate that hippocampal atrophy has functional consequences, e.g. cognitive impairment. Deposition of tau protein, formation of neurofibrillary tangles and accumulation of β-amyloid (Aβ) contributes to hippocampal atrophy together with damage caused by several other factors. Some of the factors associated with the development of hippocampal atrophy in Alzheimers disease have been identified, e.g. hypertension, diabetes mellitus, hyperlipidaemia, seizures, affective disturbances and stress, and more is being learnt about other factors.Hypertension can potentially damage the hippocampus through ischaemia caused by atherosclerosis and cerebral amyloid angiopathy. Diabetes can produce hippocampal lesions via both vascular and non-vascular pathologies and can reduce the threshold for hippocampal damage. Carriers of the apolipoprotein E (ApoE).ε4 genotype have been shown to have greater mesial temporal atrophy and poorer memory functions than non-carriers. In addition to giving rise to abnormal lipid metabolism, the ApoE-ε4 allele can affect the course of Alzheimers disease via both Aβ-dependent and -independent pathways. Repetitive seizures can increase Aβ-peptide production and cause neurotransmission dysfunction and cytoskeletal abnormalities or a combination of these. Affective disturbances and stress are proposed to increase corticosteroid-induced hippocampal damage in many different ways.In the absence of any specific markers for predicting Alzheimers disease progression, it seems appropriate to learn more about the various predictors of hippocampal atrophy that determine the progression of Alzheimers disease from mild cognitive impairment (MCI), and then attempt to address these. It would be interesting to know to what extent these predictors play a role in the development of MCI or hasten the conversion of MCI to full-blown Alzheimers disease. Finally, it would be useful to know the extent to which these predictors can worsen or aggravate existing Alzheimers disease.Of the clinically used drugs in Alzheimers disease, anticholinesterases have been shown to slow down the rate of progression of hippocampal atrophy. One study observed that the neuroprotective effect of these agents is possibly due to an anti-Aβ effect produced by cholinergic stimulation. Similarly, antihypertensive and antihyperglycaemic drugs (pioglitazone and insulin) have been shown to reduce the risk of Alzheimers disease or disease progression. Currently, there are no disease-modifying therapies available for Alzheimers disease. It has been suggested that for treatment to be most effective, the regimen must be started before significant downstream damage has occurred (i.e. before the clinical diagnosis of Alzheimers disease, at the stage of MCI or earlier). Since the hippocampus is a plastic structure and atrophy of this structure is closely related to the pathophysiology of Alzheimers disease, if we could control blood pressure, regulate blood sugar, treat behavioural and psychological symptoms, achieve satisfactory lipid lowering and maintain a seizure-free state in patients with Alzheimers disease, this may not only improve disease control but could also potentially affect the rate of disease progression. © 2011 Adis Data Information BV. All rights reserved.
Dangwal M.,Guru Gobind Singh Indraprastha University |
Kapoor S.,The Interdisciplinary Center |
Kapoor M.,Guru Gobind Singh Indraprastha University
Plant Journal | Year: 2014
Summary Chromomethylases (CMTs) are plant-specific cytosine DNA methyltransferases that are involved in maintenance of CpNpG methylation. In seed plants, histone methylation and interaction of CMT with LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) is essential for recruitment of CMT to target sites. LHP1 has been characterized as a putative component of the POLYCOMB REPRESSIVE COMPLEX1 (PRC1) in plants, and functions downstream of PRC2 to maintain genes in repressed state for orchestrated development. In the present study, we show that targeted disruption of PpCMT results in an approximately 50% reduction in global cytosine methylation levels. This affects growth of apical cells, predominantly growth of side branch initials emerging from chloronema cells. In some places, these cells develop thick walls with plasmolyzed cellular contents. Transcript accumulation patterns of genes involved in apical cell extension and metabolism of hemicelluloses, such as xyloglucans, in the primary cell walls decreased many fold in ppcmt mutant lines, as determined by real-time PCR. Using yeast two-hybrid method and bimolecular fluorescence complementation assay, we show that PpCMT and PpLHP1 interact through their chromo domains, while PpLHP1 homodimerizes through its chromo shadow domain. The results presented in this study provide insight into the role of the single chromomethylase, PpCMT, in proliferation of protonema filaments, and shed light on the evolutionary conservation of proteins interacting with these methylases in the early land plant, Physcomitrella patens. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.
Kumar R.,Guru Gobind Singh Indraprastha University |
Singh P.,Guru Gobind Singh Indraprastha University
Results in Physics | Year: 2013
125μm Thick PADC polymer samples were irradiated by 50MeV Li3+ ions and 250μm thick PADC polymer samples were irradiated by 70MeV C5+ ions. The optical absorption edge shifted towards the visible region of the spectrum with the increase of ion fluence signifying the decrease in the band gap energy in both cases. There was larger decrease in the band gap energy value in carbon ions irradiated samples as compared to lithium ions irradiated samples. Increase in number of carbon hexagon rings per cluster was verified by modified Robertson equation. The Urbach's energy calculations showed the thermal fluctuations in the band gap energy values. The FTIR spectrum showed the reduction in absorbance (higher percentage transmittance) of typical bands at higher fluences in case of lithium ion irradiation. The carbon ion irradiation showed little modification in chemical studies. © 2013 The Authors.
Kuriakose S.,Guru Gobind Singh Indraprastha University |
Satpati B.,Saha Institute of Nuclear Physics |
Mohapatra S.,Guru Gobind Singh Indraprastha University
Physical Chemistry Chemical Physics | Year: 2014
Cobalt doped ZnO nanodisks and nanorods were synthesized by a facile wet chemical method and well characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) with energy dispersive X-ray spectroscopy, photoluminescence spectroscopy, Raman spectroscopy and UV-visible absorption spectroscopy. The photocatalytic activities were evaluated for sunlight driven degradation of an aqueous methylene blue (MB) solution. The results showed that Co doped ZnO nanodisks and nanorods exhibit highly enhanced photocatalytic activity, as compared to pure ZnO nanodisks and nanorods. The enhanced photocatalytic activities of Co doped ZnO nanostructures were attributed to the combined effects of enhanced surface area of ZnO nanodisks and improved charge separation efficiency due to optimal Co doping which inhibit recombination of photogenerated charge carriers. The possible mechanism for the enhanced photocatalytic activity of Co doped ZnO nanostructures is tentatively proposed. This journal is © the Partner Organisations 2014.