985 resultados para Florida Bay Interagency Science Center
Resumo:
The synthesis, structural characterization, voltammetric experiments and antibacterial activity of [Ni(sulfisoxazole)(2)(H2O)(4)] center dot 2H(2)O and [Ni(sulfapyridine)(2)] were studied and compared with similar previously reported copper complexes. [Ni(sulfisoxazole)(2)(H2O)(4)] center dot 2H(2)O crystallized in a monoclinic system, space group C2/c where the nickel ion was in a slightly distorted octahedral environment, coordinated with two sulfisoxazole molecules through the heterocyclic nitrogen and four water molecules. [Ni(sulfapyridine)(2)] crystallized in a orthorhombic crystal system, space group Pnab. The nickel ion was in a distorted octahedral environment, coordinated by two aryl amine N from two sulfonamides acting as monodentate ligands and four N atoms (two sulfonamidic N and two heterocyclic N) from two different sulfonamide molecules acting as bidentate ligands. Differential pulse voltammograms were recorded showing irreversible peaks at 1040 and 1070 mV, respectively, attributed to Ni(II)/Ni(III) process. [Ni(sulfisoxazole)(2)(H2O)(4)] center dot 2H(2)O and [Ni(sulfapyridine)(2)] presented different antibacterial behavior against Staphylococcus aureus and Escherichia coli from the similar copper complexes and they were inactive against Mycobacterium tuberculosis. (c) 2007 Elsevier Inc. All rights reserved.
Resumo:
The impact of human activity on the sediments of Todos os Santos Bay in Brazil was evaluated by elemental analysis and (13)C Nuclear Magnetic Resonance ((13)C NMR). This article reports a study of six sediment cores collected at different depths and regions of Todos os Santos Bay. The elemental profiles of cores collected on the eastern side of Frades Island suggest an abrupt change in the sedimentation regime. Auto-regressive Integrated Moving Average (ARIMA) analysis corroborates this result. The range of depths of the cores corresponds to about 50 years ago, coinciding with the implantation of major onshore industrial projects in the region. Principal Component Analysis of the (13)C NMR spectra clearly differentiates sediment samples closer to the Subae estuary, which have high contents of terrestrial organic matter, from those closer to a local oil refinery. The results presented in this article illustrate several important aspects of environmental impact of human activity on this bay. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
The sporulation stage of the aquatic fungus Blastocladiella emersonii culminates with the formation and release to the medium of a number of zoospores, which are motile cells responsible for the dispersal of the fungus. The presence in the sporulation solution of 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a potent and selective inhibitor of nitric oxide-sensitive guanylyl cyclases, completely prevented biogenesis of the zoospores. In addition, this compound was able to significantly reduce cGMP levels, which increase drastically during late sporulation, suggesting the existence of a nitric oxide-dependent mechanism for cGMP synthesis. Furthermore, increased levels of nitric oxide-derived products were detected during sporulation by fluorescence assays using DAF-2 DA, whose signal was drastically reduced in the presence of the nitric oxide synthase inhibitor N omega-Nitro-L-arginine methyl ester (L-NAME). These results were confirmed by quantitative chemiluminescent determination of the intracellular levels of nitric oxide-derived products. A putative nitric oxide synthase (NOS) activity was detected throughout sporulation, and this enzyme activity decreased significantly when L-NAME and 1-[2-(Trifluoromethyl)phenyl]imidazole (TRIM) were added to the assays. NOS assays carried out in the presence of EGTA showed decreased enzyme activity, suggesting the involvement of calcium ions in enzyme activation. Additionally, expressed sequence tags (ESTs) encoding putative guanylyl cyclases and a cGMP-phosphodiesterase were found in B. emersonii EST database (http://blasto.iq.usp.br), and the mRNA levels of the corresponding genes were observed to increase during sporulation. Altogether, data presented here revealed the presence and expression of guanylyl cyclase and cGMP phosphodiesterase genes in B. emersonii and provided evidence of a Ca(2+)-(center dot)NO-cGMP signaling pathway playing a role in zoospore biogenesis. (C) 2009 Elsevier Inc. All rights reserved.
The shoving model for the glass-former LiCl center dot 6H(2)O: A molecular dynamics simulation study
Resumo:
Molecular dynamics (MD) simulations of LiCl center dot 6H(2)O Showed that the diffusion coefficient D, and also I lie structural relaxation time
Resumo:
In the treatment of cyclometallated dimer [Pd(dmba)(mu-Cl)](2) (dmba = N,N-dimethylbenzylamine) with AgNO(3) and acetonitrile the result was the monomeric cationic precursor [Pd(dmba)(NCMe)(2)](NO(3)) (NCMe=acetonitrile) (1). Compound 1 reacted with m-nitroaniline (m-NAN) and pirazine (pz), originating [Pd(dmba)(ONO(2))(m-NAN)] (2) and [{Pd(dmba)(ONO(2))}(2)(mu-pz)] center dot H(2)O (3), respectively. These compounds were characterized by elemental analysis, IR and NMR spectroscopy. The IR spectra of (2-3) display typical bands of monodentade O-bonded nitrate groups, whereas the NMR data of 3 are consistent with the presence of bridging pyrazine ligands. The structure of compound 3 was determined by Xray diffraction analysis. This packing consists of a supramolecular chain formed by hydrogen bonding between the water molecule and nitrato ligands of two consecutive [Pd(2)(dmba)(2)(ONO(2))2(mu-pz)] units. (c) 2008 Elsevier Ltd. All rights reserved.
Resumo:
The neutral complex [HgPh(dmpymt)] 1 (dmpymtH = 4,6-dimethylpyrimidine-2(1H)-thione) reacts with HBF(4) to give the cationic complex [HgPh(dmpymtH)][BF(4)] 2. The X-ray molecular structure of the later revealed a [2+1] coordination sphere about the mercury(II) atom (C-Hg-S and Hg center dot center dot center dot N). In the dinuclear complex [(HgPh)(2)(mu-dtu)] 3 [dtuH(2) = 2,4(1H,3H)-pyrimidinedithione or dithiouracil] the coordination spheres are also [2+1] although dissimilar regarding the Hg center dot center dot center dot N secondary bonds. NMR spectroscopy ((1)H, (13)C and (199)Hg) studies were undertaken in solution and the results discussed in the light of the X-ray structures. (C) 2008 Elsevier B. V. All rights reserved.
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group VIII is the files from the Doctoral Students' Council (DSC).
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group VII is materials about the City University of New York, transferred from the Mina Rees Library and the Provost's Office. Also included in this group are the records of the Research Foundation.
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group VI is the files of the Vice-Presidents for Finance and Administration.
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group V-D is the papers of William P. Kelly from when he was president of the GSUC (2005-2013).
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group V-C is the papers of Frances Degen Horowitz from when she was president of the GSUC (1991-2005).
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group V-B is the papers of Harold M. Proshansky from when he was president of the GSUC (1972-1990).
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group V-A is the papers of Mina S. Rees from when she was president of the GSUC (1969-1972).
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group V explains the record groups in the "Presidents' Files" series.
Resumo:
This is part of the finding aid to the Graduate School and University Center (GSUC) Archives. Record Group t IV is records from various GSUC committees.