Computational Facilities and Web-Resources: Case Study of Large Private University with Fast-Growing Clients

Speed, space and judicious sharing web-related resources are the key indicators of successful management of the computing-facilities and other web-resources of any progressive organisation. Such a case becomes much more demanding for any professional academic institution, where the majority stake-holders, that is the young student-users of web-resources, are heavily dependent on web-based learning and personal communications. Other stake holders, like administrative staff, teaching and research community of universities have web-dependence, mostly for known resources. Fast growing dependence of different categories of stake-holders of such large institutes warrants a case-study research, so as to study the present pattern of uses of web-resources, including the timing and pockets of users, and then to have a sustainable strategic planning for a better resource-management of web-resources for future. The present paper is a case study of a leading private university of Odisha (in India) with over 65,000 users of ‘university web-network' and over 7500 fixed-systems, which analyses users' time-series data of last quarter and suggests a futuristic model for optimal and effective use of - ˜Institute Web-Resources and computing facilities'. It studies both fixed-line load and load-management of wireless (Wi Fi) connections, across the 25 campuses of the Institute, scattered and geographically located within 15 sq. km

DNA Microviscosity Converts Ruthenium Polypyridyl Complexes to Effective Photosensitizers

A unique radiative decay engineering strategy using DNA microviscosity for the generation of ruthenium polypyridyl complex (RPCs) mediated singlet oxygen for selective damage of DNA and killing cancer cells is reported. This investigation also demonstarte the effect of light-driven RPCs on bacterial growth arrest, through DNA nick, and differential localization in cancer and non-cancer cells. Moreover, upon binding with DNA, RPCs experience high local microviscosity, which causes significant enhancement of the excited state lifetime and thus generates singlet oxygen. The visible-light-triggered singlet-oxygen efficiently produce nick in DNA and inhibits bacterial growth. RPCs also localize inside the nucleus of the cancer cell and in the vicinity of the nuclear membrane of non-cancerous cells, confirmed by live-cell confocal microscopy. The results provide a facile platform for the novel antibiotic intended discovery combined with cancer therapy. </div

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Not AvailableA survey was conducted during the period of April-2014–April-2016 to note the occurrence of crabs in the beach area of Digha (21°37′48.092″N 87°32′41.355″E to 21°36′9.896″N 87°27′44.098″E) at the Bay of Bengal coastal zone, India. A total of 55 species of crabs belonging to 24 genera and 13 families have been recorded during the study period. From the data it is evident that the crabs belonging to the family Ocypodidae are dominant group (28%).Not Availabl

Iridium Complexes as a Roadblock for DNA Polymerase during Amplification

Iridium-based metal complexes containing polypyridyl-pyrazine ligands show properties of DNA intercalation. They serve as roadblocks to DNA polymerase activity, thereby inhibiting the polymerization process. Upon the addition of increasing concentrations of these iridium complexes, a rapid polymerase chain reaction (PCR)-based assay reveals the selective inhibition of the DNA polymerization process. This label-free approach to study the inhibition of fundamental cellular processes via physical roadblock can offer an alternative route toward cancer therapy

Separating innocence and non-innocence of ligands and metals in complexes [(L)Ru(acac)<SUB>2</SUB>]<SUP>n</SUP> (n = -1, 0, +1; L = o-iminoquinone or o-iminothioquinone)

The diamagnetic title complexes were obtained from Ru(acac)2(CH3CN)2 and 2-aminophenol or 2-aminothiophenol. X-ray structure analysis of (L1)Ru(acac)2 (L1 = ο -iminoquinone) revealed C-C intra-ring, C-O, and C-N distances which suggest a RuIII-iminosemiquinone oxidation state distribution with antiparallel spin-spin coupling. One-electron oxidation and reduction of both title compounds to paramagnetic monocations [(L)Ru(acac)2]+ or monoanions [(L)Ru(acac)2]- occurs reversibly at widely separated potentials (Δ E &gt; 1.3 V) and leads to low-energy shifted charge transfer bands. In comparison with clearly established RuII-semiquinone or RuIII-catecholate systems the g tensor components 2.23 &gt; g1 &gt; 2.09, 2.16 &gt; g2 &gt; 2.07, and 1.97 &gt; g3 &gt; 1.88 point to considerable metal contributions to the singly occupied MO, corresponding to RuIII complexes with either o-quinonoid (→ cations) or catecholate-type ligands (→ anions) and only minor inclusion of RuIV- or RuII-iminosemiquinone formulations, respectively. The preference for the RuIII oxidation state for all accessible species is partially attributed to the monoanionic 2,4-pentanedionate (acac) co-ligands which favor a higher metal oxidation state than, e.g., neutral 2,2'-bipyridine (bpy)

First example of μ<SUB>3</SUB>-sulfido bridged mixed-valent triruthenium complex triangle Ru<SUP>III</SUP><SUB>2</SUB>Ru<SUP>II</SUP>(O,O-acetylacetonate)<SUB>3</SUB>(μ -O,O,μ-C-acetylacetonate)<SUB>3</SUB>(μ<SUB>3</SUB>-S) (1) incorporating simultaneous O,O- and γ -C-bonded bridging acetylacetonate units. Synthesis, crystal structure, and spectral and redox properties

The reaction of mononuclear ruthenium precursor [RuII(acac)2(CH3CN)2] (acac = acetylacetonate) with the thiouracil ligand (2-thiouracil, H2L1 or 6-methyl -2-thiouracil, H2L2) in the presence of NEt3 as base in ethanol solvent afforded a trinuclear triangular complex Ru3(O,O-acetylacetonate)3 (μ-O,O,γ-C-acetylacetonate)3(μ3-sulfido) (1). In 1, each ruthenium center is linked to one usual O,O-bonded terminal acetylacetonate molecule whereas the other three acetylacetonate units act as bridging functions:γ each bridges two adjacent ruthenium ions through the terminal O,O-donor centers at one end and via the γ-carbon center at the other end. Moreover, there is a μ3-sulfido bridging in the center of the complex unit, which essentially resulted via the selective cleavage of the carbon-sulfur bond of the thiouracil ligand. In diamagnetic complex 1, the ruthenium ions are in mixed valent RuIIIRuIIIRuII state, where the paramagnetic ruthenium(III) ions are antiferromagnetically coupled. The single crystal X-ray structure of 1 showed two crystallographically independent C3-symmetric molecules, Ru3(O,O-acetylacetonate)3(μ-O,O,γ-C-acetylacetonate)3(μ 3-S) (1), in the asymmetric unit. Bond distances of both crystallographically independent molecules are almost identical, but there are some significant differences in bond angles (up to 6°) and interplanar angles (up to 8°). Each ruthenium atom exhibits a distorted octahedral environment formed by four oxygen atoms, two from each of the terminal and bridging acetylacetonate units, oneγ -carbon of an adjacent acetylacetonate ligand, and the sulfur atom in the center of the complex. In agreement with the expected 3-fold symmetry of the complex molecule, the 1H and 13C NMR spectra of 1 in CDCl3 displayed signals corresponding to two types of ligand units. In dichloromethane solvent, 1 exhibited three metal center based successive quasireversible redox processes, RuIIIRuIIIRuIII-RuIIIRuIIIRuII (couple I, 0.43 V vs SCE); RuIIIRuIIIRuIV-RuIIIRuIIIRuIII (couple II, 1.12 V); and RuIIIRuIIIRuII-RuIIIRuIIRuII (couple III, -1.21 V). However, in acetonitrile solvent, in addition to the three described couples [(couple I), 0.34 V; (couple II), 1.0 V; (couple III), -1.0], one irreversible oxidative response (RuIIIRuIIIRuIV → RuIIIRuIVRuIV or oxidation of the coordinated sulfide center) appeared at Epa, 1.50 V. The large differences in potentials between the successive couples are indicative of strong coupling between the ruthenium ions in the mixed-valent states. Compound 1 exhibited a moderately strong charge-transfer (CT) transition at 654 nm and multiple ligand based intense transitions in the UV region. In the RuIIIRuIIIRuIII (1+) state, the CT band was slightly blue shifted to 644 nm; however, the CT band was further blue shifted to 520 nm on two-electron oxidation to the RuIIIRuIIIRuIV (12+) state with a reduction in intensity

Local DNA microviscosity converts ruthenium polypyridyl complexes to ultrasensitive photosensitizers

In this manuscript, we have reported how DNA binding of ruthenium polypyridyl complexes (RPCs) make them more efficient photosensitizer. The DNA binding of RPCs results in a significant enhancement of their emission intensity and excited-state lifetime. As a result, upon visible-light irradiation, these complexes generate reactive singlet oxygen, which causes selective DNA damage and kills cancer cells. This investigation also demonstrates the effect of light-driven RPCs on bacterial growth arrest through DNA nicking and differential localization in cancer and non-cancer cells. The local DNA microviscosity suppresses the non-radiative pathways which causes a large enhancement in the emission intensity and the excited state lifetime. The visible-light-triggered singlet-oxygen efficiently produces nick in DNA and inhibits bacterial growth. RPCs also localize inside the cancer cell nucleus and in the vicinity of the nuclear membrane of non-cancerous cells, confirmed by live-cell confocal microscopy. The results provide a facile platform for the novel antibiotic intended discovery combined with cancer therapy

The triruthenium complex [{(acac)<SUB>2</SUB>Ru<SUP>II</SUP>}<SUB>3</SUB>(L)] containing a conjugated diquinoxaline[2,3-a:2',3'-c]phenazine (L) bridge and acetylacetonate (acac) as ancillary ligands. Synthesis, spectroelectrochemical and EPR investigation

The compound [{(acac)2Ru}3(L)] (1) undergoes three well-separated one-electron oxidation and reduction processes. The EPR results indicate electron removal from the ruthenium(II) centres on oxidation and the occupation of a largely L-based molecular orbital on reduction. In spite of well-separated (Δ E ≥ 340 mV) oxidation no obvious intervalence charge transfer bands were detected in the Vis, NIR or IR regions, suggesting very weak electronic coupling between the metal centres in the mixed-valent intermediates 1+ and 12+. The separated (Δ E ≥ 540 mV) stepwise reduction produces weak near-infrared features associated with partially occupied π orbitals of L, the unusually high g anisotropy in the EPR spectrum of 1- is attributed to the occupation of a degenerate MO by the unpaired electron