43 research outputs found
Histopathological changes in gill, kidney and liver of an estuarine mullet, Liza parsia, induced by sublethal exposure to DDT
Liza parsia were exposed to sublethal (0.02 ppm) concentration of DDT for 15 days. The gill responded initially with copious secretion of mucus, oedematous separation of epithelial cells from the basement membrane and fusion of secondary gill lamellae. Hyperplasia of the cells lining primary gill lamellae and lamellar telangiectases (or aneurysms) was frequently seen after day 10 of exposure. Kidney exhibited hypertrophy of the epithelial cells lining proximal convoluted tubules which was followed by shrinkage in glomerular tufts, increase in Bowman's space, appearance of amorphous eosinophilic materials in the lumina of the tubules and focal necrosis on day 10 of the treatment. Hyaline droplets and casts were also encountered in the epithelial cells and lumina of the proximal tubules. Liver revealed an initial dilation of canaliculi and increased secretion of bile. Thereafter, the displacement of nuclei towards periphery of the hepatocytes, disorganization of blood sinusoids, pyknotic changes in nuclei, cytolysis and vacuolation as well as focal necrosis were noticed after day 10 of the intoxication
Astrophysical S-factor of the Be(B reaction from Coulomb dissociation of B
The Coulomb dissociation method to obtain the astrophysical S-factor,
, for the Be(B reaction at solar energies is
investigated by analysing the recently measured data on the breakup reaction
PbB,BePb at 46.5 MeV/A beam energy. Breakup cross
sections corresponding to E1, and transitions are calculated with a
theory of Coulomb excitation that includes the effects of the Coulomb recoil as
well as relativistic retardation. The interplay of nuclear and Coulomb
contributions to the breakup process is studied by performing a full quantum
mechanical calculation within the framework of the distorted-wave Born
Approximation. In the kinematical regime of the present experiment, both
nuclear as well as Coulomb-nuclear interference processes affect the pure
Coulomb breakup cross sections very marginally. The cross sections are
strongly dependent on the model used to describe the structure of B. The
value of is deduced with and without and contributions
added to the cross sections and the results are discussed.Comment: 10 pages, with 4 figures included with psfig; Physics Letters B, in
pres
Rationally designed novel Phenyloxazoline Synthase Inhibitors: chemical synthesis and biological evaluation to accelerate the discovery of new antimycobacterial antibiotics
The uncontrolled spread of drug-resistant tuberculosis (DR-TB) clinical cases necessitates the urgent discovery of newer chemotypes with novel mechanisms of action. Here, we report the chemical synthesis of rationally designed novel transition-state analogues (TSAs) by targeting the cyclization (Cy) domain of phenyloxazoline synthase (MbtB), a key enzyme of the conditionally essential siderophore biosynthesis pathway. Following bio-assay-guided evaluation of TSA analogues preferentially in iron-deprived and iron-rich media to understand target preferentiality against a panel of pathogenic and non-pathogenic mycobacteria strains, we identified a hit, i.e., TSA-5. Molecular docking, dynamics, and MMPBSA calculations enabled us to comprehend TSA-5’s stable binding at the active site pocket of MbtB_Cy and the results imply that the MbtB_Cy binding pocket has a strong affinity for electron-withdrawing functional groups and contributes to stable polar interactions between enzyme and ligand. Furthermore, enhanced intracellular killing efficacy (8 μg/mL) of TSA-5 against Mycobacterium aurum in infected macrophages is noted in comparison to moderate in vitro antimycobacterial efficacy (64 μg/mL) against M. aurum. TSA-5 also demonstrates whole-cell efflux pump inhibitory activity against Mycobacterium smegmatis. Identification of TSA-5 by focusing on the modular MbtB_Cy domain paves the way for accelerating novel anti-TB antibiotic discoveries
Cerebellar Nuclear Neurons Use Time and Rate Coding to Transmit Purkinje Neuron Pauses
Copyright: © 2015 Sudhakar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedNeurons of the cerebellar nuclei convey the final output of the cerebellum to their targets in various parts of the brain. Within the cerebellum their direct upstream connections originate from inhibitory Purkinje neurons. Purkinje neurons have a complex firing pattern of regular spikes interrupted by intermittent pauses of variable length. How can the cerebellar nucleus process this complex input pattern? In this modeling study, we investigate different forms of Purkinje neuron simple spike pause synchrony and its influence on candidate coding strategies in the cerebellar nuclei. That is, we investigate how different alignments of synchronous pauses in synthetic Purkinje neuron spike trains affect either time-locking or rate-changes in the downstream nuclei. We find that Purkinje neuron synchrony is mainly represented by changes in the firing rate of cerebellar nuclei neurons. Pause beginning synchronization produced a unique effect on nuclei neuron firing, while the effect of pause ending and pause overlapping synchronization could not be distinguished from each other. Pause beginning synchronization produced better time-locking of nuclear neurons for short length pauses. We also characterize the effect of pause length and spike jitter on the nuclear neuron firing. Additionally, we find that the rate of rebound responses in nuclear neurons after a synchronous pause is controlled by the firing rate of Purkinje neurons preceding it.Peer reviewedFinal Published versio
Evolution in the time series of vortex velocity fluctuations across different regimes of vortex flow
Chemical, isotopic and amino acid composition of Mukundpura CM2.0 (CM1) chondrite: Evidence of parent body aqueous alteration
The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/SiO2 = 1.05 in its Poorly Characterized Phases (PCP) is similar to that observed in other CM2.0 chondrites. The water content of ∼9.8 wt.% is similar to that found in many other CM chondrites. Microscopic examination of matrix shows that its terrestrial weathering grade is W0 but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules (∼7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon (2.3%) and nitrogen content and their isotopic (δ13C = −5.5‰, δ15N = 23.6‰) composition is consistent with CM2.0 classification probably bordering CM1. Several amino acids such as Alanine, Serine, Proline, Valine, Threonine, Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites. Keywords: Carbonaceous chondrite, Mukundpura, CM, Isotope, Amino aci
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Not AvailableA total of 17 high yielding salt tolerant rice varieties from diverse sources were evaluated with farmers' participation under salinity stress conditions in Andaman Islands during 2011.Not Availabl