Dams, hegemony and beyond: China’s hydro-stability in the evolving world order

Abstract Water has remained a source of contentious and cooperative politics among states since the Sumerian civilization. The field of hydro-politics, since its emergence in the 1990s, had taken note of dams as both a source of conflict between riparian neighbors owing to their threat to the life and property along the transboundary banks, and as a source of cooperation through effective water and knowledge sharing and infrastructural development, promoting peaceful negotiations in good faith in these matters. In this regard, the narrative and practice of infrastructural development by the great powers in their weaker riparian states to enhance their growth has emerged as a new means to increase great power states’ power and influence in the international arena. China, in its race against the United States, has emerged as the world’s largest dam builder, having extended its construction footprints across many parts of the globe. As rapid industrial development and resultant climate change intensifies the hitherto prevalent water crises, China, through a spate of dam-building among other things, has ensured its water, and consequently food, supply through the accumulation of real and virtual water networks, in a world where basic necessities are gradually becoming scarce. Through a descriptive study, this paper attempts to answer the question of what the implications of China’s domestic, regional and global behavior of extensive hydro-infrastructural development are beyond the contemporary economic and political gains for itself. It argues that the objectives of China’s dam-building transcend short-term economic and political gains, as it attempts to ensure the possibility of China’s long-term hydro-stability in its quest to emerge at the lead of the evolving global order

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Not AvailableThe study was conducted at Forest College and research institute, Mettupalayam, during November-2011 to March-2012, to know the effect of manures and fertilizers on biochemical parameter of the Dalbergia latifolia seedlings. Among the fourteen different treatments, the treatment with 100 mg of N, 200 mg of P2O5 and 100 mg of K2O along with vermicompost (5g), Azophos (10g) and VAM (5g) per seedlings showed significantly maximum chlorophyll ‘a’ content, chlorophyll ‘b’ and total chlorophyll content (2.00 mg g-1, 1.03 mg g-1and 3.73 mg g-1 respectively). Which was followed by 100 mg of N, 200 mg of P2O5 and 100 mg of K2O along with vermicompost (5g) and Azophos (10g) per seedlings showed seedling attributes viz., chlorophyll ‘a’ content, chlorophyll ‘b’ and total chlorophyll content (1.85 mg g-1, 0.83 mg g-1and 3.42 mg g-1 respectively). Dalbergia latifolia seedlings bio-chemical parameter viz., chlorophyll ‘a’ content, chlorophyll ‘b’ and total chlorophyll content in control was remarkably low throughout the experiment.Not Availabl

Mixed ligand copper(II) dicarboxylate complexes: the role of co-ligand hydrophobicity in DNA binding, double-strand DNA cleavage, protein binding and cytotoxicity

A few water soluble mixed ligand copper(II) complexes of the type [Cu(bimda)(diimine)] 1-5, where bimda is N-benzyliminodiacetic acid and diimine is 2,2'-bipyridine (bpy, 1) or 1,10-phenanthroline (phen, 2) or 5,6-dimethyl-1,10-phenanthroline (5,6-dmp, 3) or 3,4,7,8-tetramethyl-1,10-phenanthroline (3,4,7,8-tmp, 4) and dipyrido[3,2-d: 2', 3'-f] quinoxaline (dpq, 5), have been successfully isolated and characterized by elemental analysis and other spectral techniques. The coordination geometry around copper(II) in 2 is described as distorted square based pyramidal while that in 3 is described as square pyramidal. Absorption spectral titrations and competitive DNA binding studies reveal that the intrinsic DNA binding affinity of the complexes depends upon the diimine co-ligand, dpq (5) > 3,4,7,8-tmp (4) > 5,6-dmp (3) > phen (2) > bpy (1). The phen and dpq co-ligands are involved in the p-stacking interaction with DNA base pairs while the 3,4,7,8-tmp/5,6-dmp and bpy co-ligands are involved in respectively hydrophobic and surface mode of binding with DNA. The small enhancement in the relative viscosity of DNA upon binding to 1-5 supports the DNA binding modes proposed. Interestingly, 3 and 4 are selective in exhibiting a positive induced CD band (ICD) upon binding to DNA suggesting that they induce B to A conformational change. In contrast, 2 and 5 show CD responses which reveal their involvement in strong DNA binding. The complexes 2-4 are unique in displaying prominent double-strand DNA cleavage while 1 effects only single-strand DNA cleavage, and their ability to cleave DNA in the absence of an activator varies as 5 > 4 > 3 > 2 > 1. Also, all the complexes exhibit oxidative double-strand DNA cleavage activity in the presence of ascorbic acid, which varies as 5 > 4 > 3 > 2 > 1. The ability of the complexes to bind and cleave the protein BSA varies in the order 4 > 3 > 5 > 2 > 1. Interestingly, 3 and 4 cleave the protein non-specifically in the presence of H2O2 as an activator suggesting that they can act also as chemical proteases. It is remarkable that 2-5 exhibit cytotoxicity against human breast cancer cell lines (MCF-7) with potency higher than the widely used drug cisplatin indicating that they have the potential to act as effective anticancer drugs in a time dependent manner. The morphological assessment data obtained by using Hoechst 33258 staining reveal that 3 and 4 induce apoptosis much more effectively than other complexes. Also, the alkaline single-cell gel electrophoresis study (comet assay) suggests that the same complexes induce DNA fragmentation more efficiently than others

N,N-Ru(ii)-p-cymene-poly(N-vinylpyrrolidone) surface functionalized gold nanoparticles : from organoruthenium complex to nanomaterial for antiproliferative activity

Organometallic Ru-arene complexes are promising as anticancer agents, but the lack of tumor uptake and poor solubility in the physiological medium impede their development. In order to deal with these challenges, we developed gold nanoparticles coated with Ru(arene)-functionalized PNVP-Py, where PNVP-Py is pyridine end-functionalized poly(N-vinylpyrrolidone). It is demonstrated that these particles exhibit higher anti-proliferative activity than the individual organometallic ruthenium(ii) complex of the type [Ru(eta(6)-p-cymene)(NN)Cl]PF6, where NN is bis(4-methoxyphenylimino)acenaphthene, against colorectal adenocarcinoma cell lines. More specifically, a Ru-II(eta(6)-p-cymene) complex containing a NN bidentate ligand has been prepared and characterized by spectral studies and X-ray crystallography. To tether the isolated complex onto the surface of the AuNPs, PNVP-Py, which contains a pyridine group at one end to coordinate to the Ru-complex and a suitable functional group at the other end to bind on the surface of the AuNPs, has been prepared and utilized to obtain the macromolecular complex [Ru(eta(6)-p-cymene)(NN)(PNVP-Py)]Cl-2. Next, stable Ru(p-cym)(NN)(PNVP-Py)@AuNPs were obtained via a ligand exchange reaction of citrate-stabilized AuNPs with a macromolecular complex by a direct 'grafting to' approach and characterized well. Despite the lower DNA cleavage activity, the nanoconjugate exhibits better cytotoxicity than the individual complex against HT-29 colorectal adenocarcinoma cells on account of its enhanced permeability across the cell membrane. The AO/EB staining assay revealed that the nanoconjugate is able to induce an apoptotic mode of cell death, which was further quantitatively evaluated by Annexin V-FITC/PI double assay. An immunofluorescence assay indicated the higher potency of the nanoconjugate to inhibit cyclin D1 gene expression that is required for cancer cell growth. To the best of our knowledge, this is the first report of the modification of an organometallic Ru(arene) complex into a Ru(arene)metallopolymer-gold nanoconjugate for the development of ruthenium-based nanomedicine for cancer treatment