14,797 research outputs found
Endochironomus effusus Dutta
No full textEndochironomus effusus (Dutta) Endochironomus effusus Dutta in Dutta et al. (1994: 256). The description and placement of the adult male of Endochironomus effusus Dutta in Dutta et al. (1994) is based on an inadequate generic concept and does not conform to the diagnosis for Endochironomus Kieffer males (Cranston et al. 1989). The list of features justifying placement of E. effusus in Endochironomus does not do so. Features that negate the generic allocation (derived from the description and communication with P.K. Chaudhuri) include that that antepronotal lobes meet dorsally and do not project forward, the rounded foretibial scale lacks any spur, the tibial combs are conical and strong,, the inferior volsella is relatively short, stout and appressed along the inner gonocoxite, the superior volsella has a digitiform process arising from a broad, transverse base, and the gonostylus is fused inflexibly to the gonocoxite. Dutta et al. (1994) appeared unaware that Endochironomus acutistilus Freeman, to which they recognised affinity, had been placed by Freeman as the type of his genus Conochironomus (Freeman 1961). Although resembling Conochironomus in described features and additional ones examined by P.K. Chaudhuri (emeritus, Burdwan University, pers. comm. 29 November 2015), E. effusus differs from Conochironomus, e.g. in the purported presence of 2 acrostichals and lack of lateral antepronotals. The hypopygium (Dutta et al. 1994: fig. 2 d) closely resembles that of C. tobaterdecimus. Following re-examination of the sole remaining paratype of Endochironomus effusus by P.K. Chaudhuri (pers. comm., 2015, mensural features are similar to those in C. tobaterdecimus, excepting ‘numerous setae’ on wing vein R 4 + 5, purported presence of acrostichals and lateral antepronotals. However, the specimen is poorly mounted (P.K. Chaudhuri, pers. comm), making it impossible to assess all features required to confirm generic placement in Conochironomus and it is premature to propose a new generic combination before suitable material becomes available for evaluation. Locations for E. effusus at 27 °N in the Duar foothills of the Himalaya in West Bengal, are at elevations up to 450 m. a.s.l., which is subtropical-temperate compared to the more tropical habitats of Conochironomus in Africa and Australia. However, the most northerly sites at which definitive Conochironomus larvae have been found in Thailand, at about 19–20 °N, are at elevations above 600 m a.s.l. and also are cool subtropical to warm temperate.Published as part of Cranston, Peter S., 2016, Conochironomus (Diptera: Chironomidae) in Asia: new and redescribed species and vouchering issues, pp. 315-331 in Zootaxa 4109 (3) on page 328, DOI: 10.11646/zootaxa.4109.3.3, http://zenodo.org/record/25976
Structural Dynamics and Allosteric Signaling in Ionotropic Glutamate Receptors
No full textIonotropic glutamate receptors (iGluRs) are ligand-gated ion channels that mediate excitatory neurotransmission events in the central nervous system. All distinct classes of iGluRs (AMPA, NMDA, Kainate) are composed of an N-terminal domain (NTD) and a ligand-binding domain (LBD) in their extracellular domain, a transmembrane domain (TMD) and an intracellular carboxy-terminal domain (CTD). Ligand binding to the LBD facilitates ion channel activation. The NTDs modulate channel gating allosterically in NMDA receptors (NMDARs). A similar function of the NTD in AMPA receptors (AMPARs) is still a matter of debate. Taking advantage of recently resolved structures of the NTD and the intact AMPAR, the main focus of this dissertation is a comprehensive examination of iGluR NTD structural dynamics, ligand binding and allosteric potential of AMPARs. We use a multiscale, multi-dimensional approach using coarse-grained network models and all-atom simulations for structural analyses and information theoretic approaches for examination of evolutionary correlations. Our major contribution has been the characterization of the global motions favored by iGluR NTD architecture. These intrinsic motions favor ligand binding in NMDAR NTDs and are also shared by other iGluR NTDs. We also identified structural determinants of flexibility in AMPARs and confirmed their role through in silico mutants.
The overall similarity in collective dynamics among iGluRs hints at a putative allosteric capacity of non-NMDARs and has propelled the elucidation of interdomain and intersubunit coupling in the intact AMPAR. To this end, we identified “effector” and “sensor” regions in AMPARs using a perturbation-response technique. We identified potentially functional residues that enable information propagation between effector regions and proposed an efficient mechanism of allosteric communication based on a combination of tools including network models, graph theoretical methods and sequence analyses.
Finally, we assessed the “druggability” of iGluR NTDs using molecular dynamics simulations in the presence of probe molecules containing fragments shared by drug-like molecules. Based on our study, we offer key insights into the ligand-binding landscape of iGluR NTD monomers and dimers, and we also identify a novel ligand-binding site in AMPAR dimers. These findings open an avenue of searching for molecules able to bind to iGluR NTDs and allosterically modulate receptor activity
Rhacophorus pseudomalabaricus Vasudevan and Dutta 2000
No full textRhacophorus pseudomalabaricus Vasudevan and Dutta, 2000 Anaimalai Flying Frog (Daniels 2005) (Figures 1 C, 2 D, 3 H, 6 D, 9 A–G; Tables 1–3) Original name and description. Rhacophorus pseudomalabaricus Vasudevan and Dutta, 2000, A new species of Rhacophorus (Anura: Rhacophoridae) from the Western Ghats, India, Hamadryad, 25: 23. Name-bearing types. Holotype, BNHS (BNHM) 3095, by original designation, an adult female; Paratypes, ZSI/SRS VA/ 1078 – 79. Type locality. Andiparai Shola, (Valparai), Tamil Nadu, India. Current status of specific name. Valid name, as Rhacophorus pseudomalabaricus Vasudevan and Dutta, 2000. Other material studied/observed. KERALA: Idukki district, Kadalar, SDBDU 2011.1010 (adult male), collected by SDB on 22 September 2011; Palakkad district, Poopara, Parambikulam, SDBDU 2011.1422 (adult male), collected by SDB, RGK, AT, SG, RS & GS on 13 August 2011. TAMIL NADU: Coimbatore district, Valparai, SDBDU 1162–1165 (four adult males) and SDBDU 1160, SDBDU 1166 (two adult female), collected by SDB on 11 July 2002, ZSI/SRS VA 1078 (paratype, adult male), Andiparai Shola, BNHS 3095 (holotype, adult female), collected by K. Vasudevan on 23 January 1998, ZSI/SRS VA 1078 (paratype, adult male), collected by K. Vasudevan on 24 July 1998, WII 514 (paratype, adult male), collected by K. Vasudevan on 10 October 1998. Diagnosis. Rhacophorus pseudomalabaricus can be distinguished from known congeners by the following combination of characters: (1) large male adult size (SVL 47.2–53.6 mm); (2) green dorsal colour with light yellow webbing between fingers and toes in life; (3) finger webbing extensive, reaching beyond distal subarticular tubercle on inner side and base of disc in outer side of finger III; (4) thick dermal fringe from base of pad of toe V extends along lateral edge of tarsus to heel where it develops into broad flange with lateral projecting calcar on outer edge of heel; and (5) toe webbing extensive, reaching distal subarticular tubercle on either side of toe IV (Figure 9 F, G). Comparison. Rhacophorus pseudomalabaricus is unique by its uniform green colouration of dorsum with venation-like light grey lines in life. However, this species could be confused with Rhacophorus malabaricus due to comparable size in preservation. For differences with R. malabaricus, see ‘comparison’ of that species. Description of holotype. A detailed general description was published in Vasudevan and Dutta (2000). Variation. Measurements of three female, including holotype and six male specimens, are given in Table 2. No considerable variation in breeding and non breeding colour. Distribution and natural history. This species is currently reported from Kadalar, Poopara in Kerala and Andiparai Shola, Puduthottam in Tamil Nadu (Figure 6 D; Table 1). It is a high-altitude species found at ca. 955–1430 m asl. The Poopara specimen was located on a leaf at ca. 2 m above ground along a trek path in secondary forests on the fringe of abandoned cardamom plantations. The Kadalar specimen was located on a stem ca. 1.5 m above ground in a marshy area beside a perennial stream outside KFDC’s cardamom plantation. During breeding season the species is known to aggregate at artificial ponds (Vasudevan & Dutta 2000) and on vegetation overhanging marshy areas, ponds and streams. All collections in the present study were made between 18:00 to 20:00 hours. Species Voucher specimen Locality Accession number Source of sequences retrieved from GenBank. a. Bossuyt & Milinkovitch (2000), b. Hasan et al. (2012), NCBI, Genbank, unpublished, c. Delmore (2004), d. Meenakshi et al. (2009), NCBI, Genbank, unpublished.Published as part of Biju, S. D., Kamei, Rachunliu G., Mahony, Stephen, Thomas, Ashish, Garg, Sonali, Sircar, Gargi & Suyesh, Robin, 2013, Taxonomic review of the tree frog genus Rhacophorus from the Western Ghats, India (Anura: Rhacophoridae), with description of ontogenetic colour changes and reproductive behaviour, pp. 257-289 in Zootaxa 3636 (2) on pages 280-282, DOI: 10.11646/zootaxa.3636.2.3, http://zenodo.org/record/21852
Importance of second oscillation maxima in probing invisible neutrino decay
No full textParallel Contributed Talk at the
"XIX International Workshop on Neutrino Telescopes"
on line - 18-26 February, 2021Based on : arXiv:2012.04958
with D. Dutta, S. Goswami, D. Pramani
Heavy quarkonia in quark gluon plasma as open quantum systems
No full textDutta N. Heavy quarkonia in quark gluon plasma as open quantum systems. Bielefeld: Universitätsbibliothek; 2013
A baseline-free crack detection using nonlinear acoustics
No full textA crack detection technique based on nonlinear acoustic is developed in this study. Lead Zinconate Titanate (PZT) materials are used for exciting and sensing acoustic waves. Acoustic waves at a chosen frequency are generated using an actuating PZT transducer and they travel through the target structure before being received by a sensing PZT wafer. Unlike all undamaged medium, a cracked medium exhibits acoustic nonlinearity which is manifested as harmonics and fractional subharmonics in the power spectrum of the sensed signal. Experimental results also show that the harmonic and sub-harmonic components increase in magnitude with increasing amplitude of the input signal. The proposed technique tells the presence of cracks by looking at the aforementioned two features and obviates the need for baseline data.This research was supported by Bombardier Inc.,
Pennsylvania Infrastructure Technology Alliance (PITA)
program, and Smart Infra-Structure Technology Center
(SISTeC)
Crack Detection in Metallic Structures Using Nonlinear Electro-Magnetic Impedance Measurement
No full textA nonlinear impedance method and its potential application in baseline free crack detection in metallic structures
No full textDr Mousumee Dutta and Husband?
No full textThe Making of the ANU' - Installation Ceremony for First Chancellor of ANU, etc. - Helen Hughes, C. S. Daley, John Passmore, Susan Sergeantson, J. W. Davidson, C. Gibb, H. McQueen, Iain McCalman, J. J. Dedman, Adrien Albert, Prof. I. O. 'Junji' Orubuloye, Jack Caldwell, A. A. Conlon, Julius Stone, Bernie Sugarman J., Ernest Llewellyn, Sir Malcolm Seargent, Lauri Kennedy, William Herbert, Jacqueline Ta Quang, Sir Geoffrey Yeend, Kath Luff, Noel Butlin, Jim Perkins, Ted Hannan, J. Catt, W. Hogan, D. Rawson, Dr. Mousumee Dutta, Phil Peters, Bill Morrison, Dick Woollcott, Tony Powell & other
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