177 resultados para 7-66


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Oxovanadium(IV) complexes VO(Fc-tpy)(acac)](ClO4) (1), VO(Fc-tpy)(nap-acac)](ClO4) (2), VO(Fc-tpy)(py-acac)](ClO4) (3) and VO(Ph-tpy)(py-acac)](ClO4) (4) of 4'-ferroceny1-2,2':6',2 `'-terpyridine (Fc-tpy) and 4'-phenyl-2,2':6',2 `'-terpyridine (Ph-tpy) having monoanionic acetylacetonate (acac), naphthylacetylacetonate (nap-acac) or pyrenylacetylacetonate (py-acac) ligand were prepared, characterized and their photocytotoxicity in visible light studied. The ferrocenyl complexes 1-3 showed an intense charge transfer band near 585 nm in DMF and displayed Fc(+)/Fc and V(IV)/V(III) redox couples near 0.66 V and -0.95 V vs. SCE in DMF-0.1 M TBAP. The complexes as avid binders to calf thymus DNA showed significant photocleavage of plasmid DNA in green light (568 nm) forming center dot OH radicals. The complexes that are photocytotoxic in HeLa and MCF-7 cancer cells in visible light (400-700 nm) with low dark toxicity remain nontoxic in normal fibroblast 3T3 cells. ICP-MS and fluorescence microscopic studies show significant cellular uptake of the complexes. Photo-irradiation of the complexes causes apoptotic cell death by ROS as evidenced from the DCFDA assay. (C) 2015 Elsevier Masson SAS. All rights reserved.

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Concentration of greenhouse gases (GHG) in the atmosphere has been increasing rapidly during the last century due to ever increasing anthropogenic activities resulting in significant increases in the temperature of the Earth causing global warming. Major sources of GHG are forests (due to human induced land cover changes leading to deforestation), power generation (burning of fossil fuels), transportation (burning fossil fuel), agriculture (livestock, farming, rice cultivation and burning of crop residues), water bodies (wetlands), industry and urban activities (building, construction, transport, solid and liquid waste). Aggregation of GHG (CO2 and non-CO2 gases), in terms of Carbon dioxide equivalent (CO(2)e), indicate the GHG footprint. GHG footprint is thus a measure of the impact of human activities on the environment in terms of the amount of greenhouse gases produced. This study focuses on accounting of the amount of three important greenhouses gases namely carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) and thereby developing GHG footprint of the major cities in India. National GHG inventories have been used for quantification of sector-wise greenhouse gas emissions. Country specific emission factors are used where all the emission factors are available. Default emission factors from IPCC guidelines are used when there are no country specific emission factors. Emission of each greenhouse gas is estimated by multiplying fuel consumption by the corresponding emission factor. The current study estimates GHG footprint or GHG emissions (in terms of CO2 equivalent) for Indian major cities and explores the linkages with the population and GDP. GHG footprint (Aggregation of Carbon dioxide equivalent emissions of GHG's) of Delhi, Greater Mumbai, Kolkata, Chennai, Greater Bangalore, Hyderabad and Ahmedabad are found to be 38,633.2 Gg, 22,783.08 Gg, 14,812.10 Gg, 22,090.55 Gg, 19,796.5 Gg, 13,734.59 Gg and 91,24.45 Gg CO2 eq., respectively. The major contributors sectors are transportation sector (contributing 32%, 17.4%, 13.3%, 19.5%, 43.5%, 56.86% and 25%), domestic sector (contributing 30.26%, 37.2%, 42.78%, 39%, 21.6%, 17.05% and 27.9%) and industrial sector (contributing 7.9%, 7.9%, 17.66%, 20.25%, 1231%, 11.38% and 22.41%) of the total emissions in Delhi, Greater Mumbai, Kolkata, Chennai, Greater Bangalore, Hyderabad and Ahmedabad, respectively. Chennai emits 4.79 t of CO2 equivalent emissions per capita, the highest among all the cities followed by Kolkata which emits 3.29 t of CO2 equivalent emissions per capita. Also Chennai emits the highest CO2 equivalent emissions per GDP (2.55 t CO2 eq./Lakh Rs.) followed by Greater Bangalore which emits 2.18 t CO2 eq./Lakh Rs. (C) 2015 Elsevier Ltd. All rights reserved.

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The leaf surface usually stays flat, maintained by coordinated growth. Growth perturbation can introduce overall surface curvature, which can be negative, giving a saddle-shaped leaf, or positive, giving a cup-like leaf. Little is known about the molecular mechanisms that underlie leaf flatness, primarily because only a few mutants with altered surface curvature have been isolated and studied. Characterization of mutants of the CINCINNATA-like TCP genes in Antirrhinum and Arabidopsis have revealed that their products help maintain flatness by balancing the pattern of cell proliferation and surface expansion between the margin and the central zone during leaf morphogenesis. On the other hand, deletion of two homologous PEAPOD genes causes cup-shaped leaves in Arabidopsis due to excess division of dispersed meristemoid cells. Here, we report the isolation and characterization of an Arabidopsis mutant, tarani (tni), with enlarged, cup-shaped leaves. Morphometric analyses showed that the positive curvature of the tni leaf is linked to excess growth at the centre compared to the margin. By monitoring the dynamic pattern of CYCLIN D3;2 expression, we show that the shape of the primary arrest front is strongly convex in growing tni leaves, leading to excess mitotic expansion synchronized with excess cell proliferation at the centre. Reduction of cell proliferation and of endogenous gibberellic acid levels rescued the tni phenotype. Genetic interactions demonstrated that TNI maintains leaf flatness independent of TCPs and PEAPODs.

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The solid state structure of a new seven-membered sugar oxepane derivative, namely, p-bromo phenyl 4,5,7-tri-O-benzyl-beta-D-glycero-D-talo-septanoside is discussed, as determined through single crystal X-ray structural determination and in relation to their conformational features. The molecule adopts twist-chair as the preferred conformation, with conformational descriptor (TC2,3)-T-0,1. The solid state packing of molecules is governed by a rich network of non-covalent bonding originating from O-H center dot center dot center dot O, C-H center dot center dot center dot pi, C-H center dot center dot center dot Br and aromatic pi center dot center dot center dot pi interactions that stabilize the packing of molecules in the crystal. (C) 2015 Elsevier Ltd. All rights reserved.

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Biomechanical assays offer a good alternative to biochemical assays in diagnosing disease states and assessing the efficacy of drugs. In view of this, we have developed a miniature compliant tool to estimate the bulk stiffness of cells, particularly MCF-7 (Michigan Cancer Foundation) cells whose diameter is 12-15 mu m in suspension. The compliant tool comprises a gripper and a displacement-amplifying compliant mechanism (DaCM), where the former helps in grasping the cell and the latter enables vision-based force-sensing. A DaCM is necessary because the microscope's field of view at the required magnification is not sufficient to simultaneously observe the cell and the movement of a point on the gripper, in order to estimate the force. Therefore, a DaCMis strategically embedded within an existing gripper design leading to a composite compliant mechanism. The DaCM is designed using the kinetoelastostatic map technique to achieve a 42 nN resolution of the force. The gripper, microfabricated with SU-8 using photolithography, is within the footprint of about 10 mm by 10 mm with the smallest feature size of about 5 mu m. The experiments with MCF-7 cells suggest that the bulk stiffness of these is in the range of 8090 mN/m. The details of design, prototyping and testing comprise the paper. (C) 2015 Elsevier Ltd. All rights reserved.

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Carbon isotope compositions of carbonate rocks from similar to 2.7-Ga-old Neoarchean Vanivilas Formation of the Dharwar Supergroup presented earlier by us are re-evaluated in this study, besides oxygen isotope compositions of a few silica dolomite pairs. The purpose of such a revisit assumes significance in view of recent field evidences that suggest a glaciomarine origin for the matrix-supported conglomerate member, the Talya conglomerate, which underlies the carbonate rocks of the Vanivilas Formation. An in-depth analysis of carbon isotope data reveals preservation of their pristine character despite the rocks having been subjected to metamorphism to different degrees (from lower greenschist to lower amphibolite facies). The dolomitic member of Vanivilas Formation of Marikanive area is characterized by highly depleted delta C-13 value (up to -5 parts per thousand VPDB) and merits as the Indian example of ca. 2.7-Ga-old cap carbonate. This inference is further supported by estimated low temperature of equilibration documented by a few silica dolomite pairs from the Vanivilas Formation collected near Kalche area. These pairs show evidence for oxygen isotopic equilibrium at low temperatures (similar to 0-20 degrees C) with depleted water (delta O-18 = -21 parts per thousand to -15 parts per thousand VSMOW) of glacial origin. We propose that the mineral pairs were deposited during the deglaciation period when the ocean temperature was in its gradual restoration phase. The dolomite of Marikanive area is the first record of cap carbonates from the Indian subcontinent with Neoarchean antiquity.

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An organic solid, 4,7-dibromo-5,6-dinitro-2,1,3-benzothiadiazole, has been designed to serve as an illustrative example to quantitatively evaluate the relative merits of halogen and chalcogen bonding in terms of charge density features. The compound displays two polymorphic modifications, one crystallizing in a non-centrosymmetric space group (Z' = 1) and the other in a centrosymmetric space group with two molecules in the asymmetric unit (Z' = 2). Topological analysis based on QTAIM clearly brings out the dominance of the chalcogen bond over the halogen bond along with an indication that halogen bonds are more directional compared to chalcogen bonds. The cohesive energies calculated with the absence of both strong and weak hydrogen bonds as well as stacking interaction are indicative of the stabilities associated with the polymorphic forms.

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Andrographis lineata is an herbal medicinal plant used in traditional medicine as a substitute for Andrographis paniculata. Here, using mature leaf explants of A. lineata we demonstrate for the first time the callus induction established on MS medium containing 1.0 mg l(-1) IAA. Dried callus was subjected to solvent extraction with acetone. Further the acetone residue was separated by silica gel column chromatography, crystallized and characterized on the basis of nuclear magnetic resonance (proton and c13) and liquid chromatographic mass spectroscopy. This analysis revealed the occurrence of two known flavones namely, 7-O-methylwogonin (MW) and Echioidinin (ED). Furthermore, these compounds were tested for their cytotoxicity against leukemic cell line, CEM. We identify that ED and MW induced cytotoxicity in a time-and concentration-dependent manner. Further increase in the LDH release upon treatment with ED and MW further confirmed our cytotoxicity results against leukemic cell line. Strikingly, MW was more potent than ED when compared by trypan blue and MTT assays. Our results recapitulate the utility of callus cultures for the production of plant specific bioactive secondary metabolites instead of using wild plants. Together, our in vitro studies provide new insights of A. lineata callus cultures serving as a source for cancer chemotherapeutic agents.

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Post-transcriptional modification of viral mRNA is essential for the translation of viral proteins by cellular translation machinery. Due to the cytoplasmic replication of Paramyxoviruses, the viral-encoded RNA-dependent RNA polymerase (RdRP) is thought to possess all activities required for mRNA capping and methylation. In the present work, using partially purified recombinant RNA polymerase complex of rinderpest virus expressed in insect cells, we demonstrate the in vitro methylation of capped mRNA. Further, we show that a recombinant C-terminal fragment (1717-2183 aa) of L protein is capable of methylating capped mRNA, suggesting that the various post-transcriptional activities of the L protein are located in independently folding domains.

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The Asian elephant Elephas maximus and the African elephant Loxodonta africana that diverged 5-7 million years ago exhibit differences in their physiology, behaviour and morphology. A comparative genomics approach would be useful and necessary for evolutionary and functional genetic studies of elephants. We performed sequencing of E. maximus and map to L. africana at similar to 15X coverage. Through comparative sequence analyses, we have identified Asian elephant specific homozygous, non-synonymous single nucleotide variants (SNVs) that map to 1514 protein coding genes, many of which are involved in olfaction. We also present the first report of a high-coverage transcriptome sequence in E. maximus from peripheral blood lymphocytes. We have identified 103 novel protein coding transcripts and 66-long non-coding (lnc)RNAs. We also report the presence of 181 protein domains unique to elephants when compared to other Afrotheria species. Each of these findings can be further investigated to gain a better understanding of functional differences unique to elephant species, as well as those unique to elephantids in comparison with other mammals. This work therefore provides a valuable resource to explore the immense research potential of comparative analyses of transcriptome and genome sequences in the Asian elephant.

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Melt spun ribbons of Fe95-x Zr (x) B4Cu1 with x = 7 (Z7B4) and 9 (Z9B4) alloys have been prepared, and their structure and magnetic properties have been evaluated using XRD, DSC, TEM, VSM, and Mossbauer spectroscopy. The glass forming ability (GFA) of both alloys has been calculated theoretically using thermodynamical parameters, and Z9B4 alloy is found to possess higher GFA than that of Z7B4 alloy which is validated by XRD results. On annealing, the amorphous Z7B4 ribbon crystallizes into nanocrystalline alpha-Fe, whereas amorphous Z9B4 ribbon shows two-stage crystallization process, first partially to bcc solid solution which is then transformed to nanocrystalline alpha-Fe and Fe2Zr phases exhibiting bimodal distribution. A detailed phase analysis using Mossbauer spectroscopy through hyperfine field distribution of phases has been carried out to understand the crystallization behavior of Z7B4 and Z9B4 alloy ribbons. In order to understand the phase transformation behavior of Z7B4 and Z9B4 ribbons, molar Gibbs free energies of amorphous, alpha-Fe, and Fe2Zr phases have been evaluated. It is found that in case of Z7B4, alpha-Fe is always a stable phase, whereas Fe2Zr is stable at higher temperature for Z9B4. (C) The Minerals, Metals & Materials Society and ASM International 2015

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Two new azide bridged copper(II) coordination polymer compounds, Cu-7(N-3)(14)(C3H10N2)(C4H13N3)]n (I) and Cu-7(N-3)(14)(C3H10N2)(C5H15N3)(2)](n) (II) where C3H10N2 = 1,2-diaminopropane (1,2-DAP); C4H13N3 = di-ethylenetriamine (DETA); C5H15N3 = N-2-aminoethyl-1,3-propanediamine (AEDAP)] were prepared by employing a room temperature diffusion technique involving three layers. Single crystal studies reveal that both compounds I and II, have similar connectivity forming Cu7 clusters through end-on (EO) bonding of the azide. The Cu-7 clusters are connected through end-to-end (EE) connectivity of the azides forming three-dimensional structures. Magnetic studies confirmed the ferromagnetic interactions within the Cu-7 units and revealed the occurrence of concomitant ferro- and antiferro-magnetic interactions between these clusters. As a result I behaves as a weak-ferromagnet with T-C = 10 K.