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Delhi, India

The University of Delhi is a public central university located in Delhi, India. It is the premier university of the country and is known for its high standards in teaching and research, as well as the eminent scholars it attracts to its faculty.It was established in 1922 as a unitary, teaching and residential university by an Act of the then Central Legislative Assembly. The President of India is the Visitor, the Vice President is the Chancellor and the Chief Justice of the Supreme Court of India is the Pro-Chancellor of the University. Ever since its inception, a strong commitment to excellence in teaching and research has made the University of Delhi a role-model and path-setter for other universities in the country. Its rich academic tradition has always attracted the most talented students who later on go on to make important contributions to their society. Wikipedia.

Pratap R.,University of Delhi | Ram V.J.,University of Lucknow
Chemical Reviews | Year: 2014

A study focuses on providing information about the natural products of chromene, furochromenes, pyranochromenes, and benzochromene ring systems, along with the synthesis of various aromatized and partially reduced chromenes, benzo-, and naphtho-fused chromenes, thiochromenopyrans, and their applications in synthetic organic chemistry for the construction of numerous diverse compounds. It is demonstrated that the presence of nitro group at C-5 in XVIIa,b affects the chemical shifts of H-4 and H-6 protons, and they resonate downfield as compared to respective protons of XVIIc due to the presence of electron-withdrawing substituents. It has also been observed that various substituted 2H-chromenes isolated from the leaves of Orthosiphom aristatus have been used as traditional medicine for the treatment of hypertension and diabetes. Source

Deb M.,University of Delhi
Ore Geology Reviews | Year: 2014

In this overview, the Precambrian metallogeny in the Indian shield has been summarized in the backdrop of the evolution of different crustal domains and their linkages to the geodynamic history of the shield. The northern cratonic block (NCB) of the Indian shield is constituted by the Bundelkhand massif (BM), Aravalli-Delhi orogenic belt (ADOB), Shillong plateau and the Himalayan Proterozoic belts and is separated from the larger southern cratonic block (SCB) comprising the Singhbhum craton (SC), Bastar craton (BC), Dharwar craton (DC, including WDC, EDC as well as the Southern Granulite Terrain (SGT)) and the Eastern Ghat mobile belt (EGMB) by the ENE-WSW-trending Central Indian Tectonic Zone (CITZ). These two cratonic blocks are constituted by a few distinct crustal domains: the Archean cratonic nuclei and the Gneissic complexes with the granulitic or granite-greenstone terranes and the Proterozoic mobile belts and intra-cratonic basins, along with the anorogenic volcano-plutonic complexes and mafic dyke swarms. Within the various litho-tectonic domains of the Indian shield are concentrated vast resources of iron, manganese and aluminum and notable resources of chromium, copper, lead, zinc and uranium. There are also significant reserves of gold and tungsten as well as rare concentration of tin and platinoid metals. Titanium along with thorium and other REE are now largely concentrated in coastal placer deposits. Out of these, the Al and REE (including Th and Ti) resources, although derived from Precambrian rocks, are the products of metallogenic processes in the Mesozoic and Cenozoic eras, and have been left out of the discussion.Metallogeny in the Indian shield spanned over a long period of 2.9. Gyr (~. 3.6 to 0.7. Ga) during five specific epochs. The earliest mineralization (+. 3.5. Ga) is recorded from a BIF in SC. Paleo- to Mesoarchean (~. 3.3 to 3.1. Ga) saw the formation of Ti-V-Fe, Cr. +. PGM, Au, Cu and Fe (BIF) in WDC and SC respectively. Intense and economically important metallogeny took place in Neoarchean (2.7 to 2.5. Ga) in SC, BC and DC represented by Fe, Mn, Cu-Mo, Sn, and Au and in Paleo- to Mesoproterozoic (2.2 to 1.5. Ga) in the mobile belts of SC, CITZ, ADOB and the Himalaya (Au, Cu-U, P-Fe, Mn, Zn-Pb-Cu, Pb-Zn deposits) and in intra-cratonic basins (Mn, Pb-Zn, U). In Neoproterozoic (1.0-0.75. Ga), the western fringe of ADOB saw VMS-type Zn-Pb-Cu and Zn-Cu mineralization as well as granite-related Sn-W deposits. Three of these metallogenic epochs coincide closely with Precambrian Supercontinent assembly of Kenorland (~. 2.7. Ga), Columbia (~. 1.8) and Rodinia (~. 1.0. Ga) respectively, as well as with the peaks of juvenile crustal growth in Neoarchean and Paleoproterozoic. © 2013 Elsevier B.V. Source

Kamei R.G.,University of Delhi
Proceedings. Biological sciences / The Royal Society | Year: 2012

The limbless, primarily soil-dwelling and tropical caecilian amphibians (Gymnophiona) comprise the least known order of tetrapods. On the basis of unprecedented extensive fieldwork, we report the discovery of a previously overlooked, ancient lineage and radiation of caecilians from threatened habitats in the underexplored states of northeast India. Molecular phylogenetic analyses of mitogenomic and nuclear DNA sequences, and comparative cranial anatomy indicate an unexpected sister-group relationship with the exclusively African family Herpelidae. Relaxed molecular clock analyses indicate that these lineages diverged in the Early Cretaceous, about 140 Ma. The discovery adds a major branch to the amphibian tree of life and sheds light on both the evolution and biogeography of caecilians and the biotic history of northeast India-an area generally interpreted as a gateway between biodiversity hotspots rather than a distinct biogeographic unit with its own ancient endemics. Because of its distinctive morphology, inferred age and phylogenetic relationships, we recognize the newly discovered caecilian radiation as a new family of modern amphibians. Source

Sharma A.,University of Delhi
Progress in Biophysics and Molecular Biology | Year: 2013

In trangenerational epigenetic inheritance, phenotypic information not encoded in DNA sequence is transmitted across generations. In germline-dependent mode, memory of environmental exposure in parental generation is transmitted through gametes, leading to appearance of phenotypes in the unexposed future generations. The memory is considered to be encoded in epigenetic factors like DNA methylation, histone modifications and regulatory RNAs. Environmental exposure may cause epigenetic modifications in the germline either directly or indirectly through primarily affecting the soma. The latter possibility is most intriguing because it contradicts the established dogma that hereditary information flows only from germline to soma, not in reverse. As such, identification of the factor(s) mediating soma to germline information transfer in transgenerational epigenetic inheritance would be pathbreaking. Regulatory RNAs and hormone have previously been implicated or proposed to play a role in soma to germline communication in epigenetic inheritance. This review examines the recent examples of gametogenic transgenerational inheritance in plants and animals in order to assess if evidence of regulatory RNAs and hormones as mediators of information transfer is supported. Overall, direct evidence for both mobile regulatory RNAs and hormones is found to exist in plants. In animals, although involvement of mobile RNAs seems imminent, direct evidence of RNA-mediated soma to germline information transfer in transgenerational epigenetic inheritance is yet to be obtained. Direct evidence is also lacking for hormones in animals. However, detailed examination of recently reported examples of transgenerational inheritance reveals circumstantial evidence supporting a role of hormones in information transmission. © 2012 Elsevier Ltd. Source

Jain A.K.,University of Delhi
Journal of Bone and Joint Surgery - Series B | Year: 2010

The dismal outcome of tuberculosis of the spine in the pre-antibiotic era has improved significantly because of the use of potent antitubercular drugs, modern diagnostic aids and advances in surgical management. MRI allows the diagnosis of a tuberculous lesion, with a sensitivity of 100% and specificity of 88%, well before deformity develops. Neurological deficit and deformity are the worst complications of spinal tuberculosis. Patients treated conservatively show an increase in deformity of about 15°. In children, a kyphosis continues to increase with growth even after the lesion has healed. Tuberculosis of the spine is a medical disease which is not primarily treated surgically, but operation is required to prevent and treat the complications. Panvertebral lesions, therapeutically refractory disease, severe kyphosis, a developing neurological deficit, lack of improvement or deterioration are indications for surgery. Patients who present with a kyphosis of 60° or more, or one which is likely to progress, require anterior decompression, posterior shortening, posterior instrumented stabilisation and anterior and posterior bone grafting in the active stage of the disease. Late-onset paraplegia is best prevented rather than treated. The awareness and suspicion of an atypical presentation of spinal tuberculosis should be high in order to obtain a good outcome. Therapeutically refractory cases of tuberculosis of the spine are increasing in association with the presence of HIV and multidrug-resistant tuberculosis. ©2010 British Editorial Society of Bone and Joint Surgery. Source

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