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Two new Mn(II) complexes,trans-[Mn(L1-L2)2(NCS)2] (1–2) with triaryltriazole (1, L1 = 3-(p-bromophenyl)-4-phenyl-5-(2-pyridyl)-1,2,4-triazole;2, L2 = 3,4-bis(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole), have been synthesized and structurally characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray crystallography. Crystallographic studies revealed that both1and2contain a distorted octahedral [MnN6] core with twotrans-disposed NCS−ions. The L1 ligand,1and2, together with four known homologous Mn(II) complexes,trans-[Mn(L3-L6)2(NCS)2] (3–6) (3, L3 = 3-(p-methoxyphenyl)-4-(p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazole;4, L4 = 3-(p-methoxyphenyl)-4-(p-bromophenyl)-5-(2-pyridyl)-1,2,4-triazole;5, L5 = 3-(p-chlorophenyl)-4-(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole;6, L6 = 3,5-bis(2-pyridyl)-4-(p-methylphenyl)-1,2,4-triazole), were testedin vitrofor their antibacterial activities against two Gram-positive bacterial strains and two Gram-negative bacterial strains by the MTT method. The results indicate that1exhibited better activity than Penicillin and Kanamycin againstPseudomonas aeruginosaand also better than its free L1 ligand. [ABSTRACT FROM PUBLISHER]

Moderate Resolution Imaging Spectroradiometer (MODIS) continuously monitors gross primary production (GPP), which is an extremely important component of carbon cycling, at the global scale. Uncertainties about MODIS GPP limit our ability to accurately quantify GPP at the regional scales. The Collection 6 MODIS/Terra and MODIS/Aqua GPP products (i.e. MOD17A2H and MYD17A2H) were compared with the estimated GPP (GPPEC) by eddy covariance measurements in an alpine meadow in the Northern Tibetan Plateau during three consecutive growing seasons of 2005-2007. The Collection 6 MODIS/Terra and MODIS/Aqua fractional photosynthetically active radiation (FPAR) products (i.e. MOD15A2H and MYD15A2H) were also validated. The MOD17A2H and MYD17A2H products tended to overestimate GPPEC by 2.17% and 7.35% in 2005-2007, respectively, although these differences were not significant. The MOD15A2H and MYD15A2H products also tended to overestimate ground-based FPAR (FPARG) by 20.31% and 24.73% in 2005-2007, respectively. The overestimation of FPAR resulted in about 17.51-23.97% overestimation of GPPEC. The default maximum light-use efficiency (εmax) of 0.86 g C MJ-1 only underestimated the ground-based εmax (0.88 g C MJ-1) by 2.27%, which in turn resulted in about 2.13-2.72% underestimation of GPPEC. The meteorology data errors only caused about 0.48-1.06% underestimation of GPPEC. Therefore, although MODIS Collection 6 GPP had a very high accuracy, the input parameters had relative greater errors in the alpine meadow of the Northern Tibetan Plateau. The differences between MODIS GPP and GPPEC mainly resulted from FPAR, followed by εmax and meteorological data. [ABSTRACT FROM AUTHOR]

Three pyrrolyl-substituted triaryltriazoles, 3-(N-methyl-2-pyrrolyl)-4-(p-R-phenyl)-5-(2-pyridyl)-1,2,4-triazole (L1: R = MeO; L2: R = Cl; L3: R = Br), and their mononuclear iron(II) complexes,trans-[Fe(L1–3)2(NCS)2]∙2MeOH (1: L1;2: L2;3: L3), have been synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray crystallography. Crystallographic studies revealed that1–3are isomorphous and crystallize in the triclinic space groupP-1. All the complexes have a similar octahedral [FeN6] core with twotrans-NCS−ions. Each ligand adopts a chelating bidentate coordination mode via the pyridyl N and one N of the triazole. Intermolecular O–H⋯O hydrogen bonding and C–H⋯πinteractions link the molecules of1–3to form a 1-D chain or 2-D framework. Variable-temperature magnetic susceptibility measurements indicated that all the complexes remained in a high-spin state from 1.8 to 300 K and had a weak antiferromagnetic interaction. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) is the most prevalent mosquito-borne viral pathogen in humans. There are 390 million human infections each year, with 96 million infections exhibiting disease symptoms. Currently, there is no clinically approved vaccine and antiviral for DENV. The four serotypes of DENV (DENV-1, -2, -3 and -4) have 25-40% variation at the amino acid level. Such variation has posed challenges for the development of a tetravalent vaccine and therapeutics. [ABSTRACT FROM AUTHOR]

A new parameterized DFP method is proposed in (Zhang and Pan [35]) via parameterizing the traditional DFP updating formula by a parameter θkin eachk-th iteration. Preliminary but favorable computational experiments are reported and indicate that the parameterized DFP method has a better numerical performance than the traditional DFP method which corresponds to θk ≡ 1 in each iteration. To lay a solid ground for the parameterized DFP method, in this article, we provide the rigorous theoretical analysis for the parameterized DFP method by showing that the positive definiteness of the updating matrices {Bk} is retained, the local linear and superlinear convergence of the generated sequence {xk} are achievable if θkis chosen in the intervals [0, 2], (0, 1] and, respectively. We also discuss some practical strategies in selecting the parameter θk, which are helpful in stabilizing the traditional DFP method. [ABSTRACT FROM PUBLISHER]

A nickel(II) complex, [NiL(phen)2]L·5H2O (HL = 2-phenyl-4-selenazole carboxylic acid, C10H7O2NSe, phen = 1,10-phenanthroline), was synthesized and characterized by elemental analysis and IR. The single crystal structure was determined by single-crystal X-ray diffraction. C88H78N12Ni2O19Se4crystallized in the triclinic system, space groupPī. The interaction between the complex and the calf thymus DNA was studied by an ethidium bromide fluorescent probe. The antibacterial activities of the complex and ligand against five species of bacteria,Escherichia coli,Staphylococcus epidermidis,Streptococcus viridans,Staphylococcus aureusandAcinetobacter baumanii, were tested. The anticancer activities of the complex against human pancreatic cancer line PANC-28 and human hepatocarcinoma line HuH7 were also studied by employing an MTT assay. [ABSTRACT FROM AUTHOR]

Large-scale atmospheric systems, such as the Southern Oscillation, North Atlantic Oscillation, and so on, are important climatic change indicators over the northern hemisphere. These systems play essential roles in regional-to-continental scale climate fluctuation and vegetation activity in response to global change. Using the Pathfinder AVHRR NDVI (Advanced Very High Resolution Radiometer Normalized Difference Vegetation Index) data for the period 1982-2000, the authors investigated the relationship of the inter-annual variations of spring NDVI to nine large-scale climate indices. On average, 57.2% of the satellite-sensed NDVI variance was explained. These climate indices also accounted for a large portion of the trends in NDVI as observed in five regions, namely, north-west North America (climate-related trend was 18.2%/10 years), south-eastern North America (5.8%/10 years), Europe (6.9% /10 years), high-latitude Asia (12.4%/10 years), and East Asia (8.0%/10 years). The results are useful for understanding and predicting the regional-to-continental NDVI variations in response to global climate change. [ABSTRACT FROM AUTHOR]