Proton-transfer compounds with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfamethazine): the structures and hydrogen-bonding in the salts with 5-nitrosalicylic acid and picric acid

The structures of the anhydrous proton-transfer compounds of the sulfa drug sulfamethazine with 5-nitrosalicylic acid and picric acid, namely 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2-hydroxy-5-nitrobenzoate, C12H15N4O2S(+)·C7H4NO4(-), (I), and 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2,4,6-trinitrophenolate, C12H15N4O2S(+)·C6H2N3O7(-), (II), respectively, have been determined. In the asymmetric unit of (I), there are two independent but conformationally similar cation-anion heterodimer pairs which are formed through duplex intermolecular N(+)-H...Ocarboxylate and N-H...Ocarboxylate hydrogen-bond pairs, giving a cyclic motif [graph set R2(2)(8)]. These heterodimers form separate and different non-associated substructures through aniline N-H...O hydrogen bonds, one one-dimensional, involving carboxylate O-atom acceptors, the other two-dimensional, involving both carboxylate and hydroxy O-atom acceptors. The overall two-dimensional structure is stabilized by π-π interactions between the pyrimidinium ring and the 5-nitrosalicylate ring in both heterodimers [minimum ring-centroid separation = 3.4580 (8) Å]. For picrate (II), the cation-anion interaction involves a slightly asymmetric chelating N-H...O R2(1)(6) hydrogen-bonding association with the phenolate O atom, together with peripheral conjoint R1(2)(6) interactions between the same N-H groups and O atoms of the ortho-related nitro groups. An inter-unit amine N-H...Osulfone hydrogen bond gives one-dimensional chains which extend along a and inter-associate through π-π interactions between the pyrimidinium rings [centroid-centroid separation = 3.4752 (9) Å]. The two structures reported here now bring to a total of four the crystallographically characterized examples of proton-transfer salts of sulfamethazine with strong organic acids.

2,4-二甲基戊二烯基稀土配合物的合成

通过元素分析、红外光谱、核磁共振谱、热重分析、晶体结构的测定以及对化合物水解产物的分析。确认合成了下列配合物: 〔η~5-2,4-(CH_3)_2C_5H_5〕LnCl_2·3THF(Ln=Nd,Sm,Gd), 〔η~5-2,4-(C_3H)_2C_5H_5〕_2LnCl·THF(Ln=Nd,Sm), 〔η~5-2,4-(CH_3)_2C_5H_5)_3Ln(Ln=La,Sm,Gd), (2,4-(CH_3)_2C_5H_5=2,4-二甲基戊二烯基。 THF=四氢呋喃

4-6岁儿童对情绪表达规则的认知发展研究

情绪表达规则是指一个人应当在恰当的情境中表达恰当的情绪。对情绪表达规则的认知发展是个体社会能力发展的一个重要方面，因此这一主题引起了国内外众多研究者的重视。但目前对童年早期儿童的研究中，大多数只考查了儿童对情绪的外显表达与内隐真实体验的区分，没有同时考查儿童对需要使用情绪表达规则的情境的认知，不能全面真实地揭示儿童对情绪表达规则的认知发展。在本研究中，以个别访谈法考查了4－6岁儿童同一个体在这两个指标上对情绪表达规则认知的发展，以及发展中的个别差异和个体内部差异，并进一步了解情境因素以及心理理论能力、执行抑制能力的发展对它们的影响。主要结果如下： （1）4－6岁儿童对情绪表达规则的认知能力随年龄增长而提高：4岁尚处于发展的萌芽水平，5岁和6岁都处于发展的过渡水平。对于同一年龄的儿童，对情绪表达规则的认知发展存在较大的个体之间的差异。 （2）4－6岁儿童对情绪表达规则的认知也存在较大的个体内部差异：对表情伪装的认知滞后于对需要使用情绪表达规则的情境的认知，对言语伪装的认知优于对表情伪装的认知；在对情绪表达规则的使用中，自我定向的占多数，其次是他人定向，规则定向所占的比例最少。随年龄的增长，自我定向的比例减少，他人定向的比例增多。 （3）情境变量影响4－6岁儿童对情绪表达规则的认知：与同伴交往情境中对需要使用情绪表达规则的情境的认知、对言语伪装的认知优于与长辈交往情境中的有关认知；对需要掩藏消极情绪情境中对表情伪装的认知要优于对需要掩藏积极情绪情境中表情伪装的认知。 （4）4－6岁儿童心理理论能力的发展和执行抑制能力的发展与其对情绪表达规则的认知发展有关。 （5）有关情绪表达规则的提示能够促进儿童对情绪隐私的认知，促进的效果随年龄的增长而提高，6岁的效果最好。

Aging kinetics in the Cu-8 wt.% Al alloy with Ag additions

The influence of additions of 2, 4, 6, 8, 10 and 12 wt.% Ag in the isothermal aging kinetics of the Cu-8 wt.% Al alloy was studied using microhardness measurements, differential scanning calorimetry, optical and scanning electron microscopy and X-ray diffractometry. The results indicate that the presence of silver is responsible for the shift of the equilibrium concentration to higher Al contents, allowing the formation of the gamma(1) phase (Al4Cu9) in this alloy. For Ag additions up to 6% the dominant kinetic process is Ag precipitation and for additions from 8 to 12% Ag the nucleation of the perlitic phase dominates. (C) 2003 Elsevier B.V. B.V. All rights reserved.

Determinação das energias de ativação para nucleação de precipitados e difusão da prata na liga cu-2%al com adições de prata

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of silver additions on the thermal behavior of the Cu-8 mass% Al alloy

The influence of additions of 2, 4, 6, 8, 10 and 12 mass% Ag on the thermal behavior of the Cu-8 mass% Al alloy was studied using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffractometry (XRD). The results indicate that the presence of silver introduces new thermal events, due to the formation of a silver-rich phase and, for additions of 10 and 12 mass% Ag, it is possible to verify the formation of the gamma (1) phase (Cu9Al4) and the metastable transitions which are only observed in alloys with a minimum of 9 mass% Al.

Caco-2 cells cytotoxicity of nifuroxazide derivatives with potential activity against Methicillin-resistant Staphylococcus aureus (MRSA)

It is important to determine the toxicity of compounds and co-solvents that are used in cell monolayer permeability studies to increase confidence in the results obtained from these in vitro experiments. This study was designed to evaluate the cytotoxicity of new nifuroxazide derivatives with potential activity against Methicillin-resistant Staphylococcus aureus (MRSA) in Caco-2 cells to select analogues for further in vitro permeability analyses. In this study, nitrofurantoin and nifuroxazide, in addition to 6 furanic and 6 thiophenic nifuroxazide derivatives were tested at 2, 4, 6, 8 and 10 mu g/mL. In vitro cytotoxicity assays were performed according to the MTT (methyl tetrazolium) assay protocol described in ISO 10993-5. The viability of treated Caco-2 cells was greater than 83% for all tested nitrofurantoin concentrations, while those treated with nifuroxazide at 2, 4 and 6 mu g/mL had viabilities greater than 70%. Treatment with the nifuroxazide analogues resulted in viability values greater than 70% at 2 and 4 mu g/mL with the exception of the thiophenic methyl-substituted derivative, which resulted in cell viabilities below 70% at all tested concentrations. Caco-2 cells demonstrated reasonable viability for all nifuroxazide derivatives, except the thiophenic methyl-substituted compound. The former were selected for further permeability studies using Caco-2 cells. (C) 2012 Elsevier Ltd. All rights reserved.

Reports of cases argued and determined in the courts of Exchequer and Exchequer chamber, from Hiliary term, 6 Will. IV, to [Easter term, 10 Vict.]...both inclusive. [1836-1847] With tables of the cases and principal matters.

Vol. 1. 1847: v. 2-4,6-8,13-14, 1846: v. 5,9,11-12, 1852: v. 10, 1845: v. 15, 1848: v. 16, 1849.

1H-1,3-Diazepines, 5H-1,3-diazepines, 1,3-diazepinones, and 2,4-diazabicyclo[3.2.0]heptenes

Tetrazolo[1,5-a] pyridines/ 2-azidopyridines 1 undergo photochemical nitrogen elimination and ring expansion to 1,3-diazacyclohepta-1,2,4,6-tetraenes 3, which react with alcohols to afford 2-alkoxy-1H-1,3-diazepines 4 (5), with secondary amines to 2-dialkylamino-5H-1,3-diazepines 16, sometimes via isolable 2-dialkylamino-1H-1,3-diazepines 15, and with water to 1,3-diazepin-2-ones 19. The latter are also obtained by elimination of isobutene or propene from 2-tert-butoxy- or 2-isopropoxy-1H-1,3-diazepines 4 or 5. 1,3-Diazepin-2-one 22B and 1,3-diazepin-4-one 24 were obtained from hydrolysis of the corresponding 4-chlorodiazepines. Diazepinones 19 undergo photochemical ring closure to diazabicycloheptenones 25 in high yields. The 2-alkoxy-1H-1,3-diazepines 4 and 5 interconvert by rapid proton exchange between positions N1 and N3. The free energies of activation for the proton exchange were measured by the Forsen - Hoffman method as DeltaGdouble dagger(298) = 16.2 +/- 0.6 kcal mol(-1) as an average for 4a - c in CD2Cl2, acetone-d(6), and methanol-d(4), and 14.1 +/- 0.6 kcal mol(-1) for 4c in acetone/D2O. The structures of 2-methoxy-5,6-bis( trifluoromethyl)-1H-1,3-diazepine 4k, 1,2-dihydro-4-diethylamino-5H-1,3-diazepin-2-one 22bB, and diazabicycloheptanone 26 were determined by X-ray crystallography. The former represents the first reported X-ray crystal structure of any monocyclic N-unsubstituted 1H-azepine.

Long-term impacts of harvest residue management on nutrition, growth and productivity of an exotic pine plantation of sub-tropical Australia

Residue retention is an important issue in evaluating the sustainability of production forestry. However, its long-term impacts have not been studied extensively, especially in sub-tropical environments. This study investigated the long-term impact of harvest residue retention on tree nutrition, growth and productivity of a F1 hybrid (Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis) exotic pine plantation in sub-tropical Australia, under three harvest residue management regimes: (1) residue removal, RR0; (2) single residue retention, RR1; and (3) double residue retention, RR2. The experiment, established in 1996, is a randomised complete block design with 4 replicates. Tree growth measurements in this study were carried out at ages 2, 4, 6, 8 and 10 years, while foliar nutrient analyses were carried out at ages 2, 4, 6 and 10 years. Litter production and litter nitrogen (N) and phosphorus (P) measurements were carried out quarterly over a 15-month period between ages 9 and 10 years. Results showed that total tree growth was still greater in residue-retained treatments compared to the RR0 treatment. However, mean annual increments of diameter at breast height (MAID) and basal area (MAIB) declined significantly after age 4 years to about 68-78% at age 10 years. Declining foliar N and P concentrations accounted for 62% (p < 0.05) of the variation of growth rates after age 4 years, and foliar N and P concentrations were either marginal or below critical concentrations. In addition, litter production, and litter N and P contents were not significantly different among the treatments. This study suggests that the impact of residue retention on tree nutrition and growth rates might be limited over a longer period, and that the integration of alternative forest management practices is necessary to sustain the benefits of harvest residues until the end of the rotation.

1,3-Dipolar cycloaddition reaction of ?,?-unsaturated esters and lactones with diazomethane

1,3-Dipolar cycloaddition of diazomethane to the alpha,beta-unsaturated esters and lactones such as 2-4, 6-8, 10 and 13 occurs in a stereoselective manner affording conjugated Delta(2)-pyrazolines. E and Z isomers of D-mannitol lead to identical product which was cyclised to investigate the absolute stereochemistry of the product. The regiospecificities of all the reactions are consistent with FMO coefficients obtained through AM1 calculations.

Enhancing the photocytotoxic potential of curcumin on terpyridyl lanthanide(III) complex formation

Lanthanide(III) complexes Ln(R-tpy)(cur)(NO3)(2)] (Ln = La(III) in 1, 2; Gd(III) in 5, 6) and Ln(R-tpy)(scur)(NO3)(2)] (Ln = La(III) in 3, 4; Gd(III) in 7, 8), where R-tpy is 4'-phenyl-2,2':6',2 `'-terpyridine (ph-tpy in 1, 3, 5, 7), 4'-(1-pyrenyl)-2,2':6',2 `'-terpyridine (py-tpy in 2, 4, 6, 8), Hcur is curcumin (in 1, 2, 5, 6) and Hscur is diglucosylcurcumin (in 3, 4, 7, 8), were prepared and their DNA photocleavage activity and photocytotoxicity studied. Complexes La(ph-tpy)(cur)(NO3)(2)] (1) and Gd(ph-tpy)(cur)(NO3)(2)] (5) were structurally characterized. The complexes in aqueous-DMF showed an absorption band near 430 nm and an emission band near 515 nm when excited at 420 nm. The complexes are moderate binders to calf-thymus DNA. They cleave plasmid supercoiled DNA to its nicked circular form in UV-A (365 nm) and visible light (454 nm) via O-1(2) and (OH)-O-center dot pathways. The complexes are remarkably photocytotoxic in HeLa cells in visible light (lambda = 400-700 nm) and are non-toxic in the dark. FACScan analysis of the HeLa cells treated with 2 and 4 showed cell death via an apoptotic pathway. Nuclear localization of 1-4 is evidenced from confocal imaging on HeLa cells. The hydrolytic instability of curcumin gets significantly reduced upon binding to the lanthanide ions while retaining its photocytotoxic potential.

Density Functional Theoretical Modeling, Electrostatic Surface Potential and Surface Enhanced Raman Spectroscopic Studies on Biosynthesized Silver Nanoparticles: Observation of 400 pM Sensitivity to Explosives

Interaction of adsorbate on charged surfaces, orientation of the analyte on the surface, and surface enhancement aspects have been studied. These aspects have been explored in details to explain the surface-enhanced Raman spectroscopic (SERS) spectra of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW or CL-20), a well-known explosive, and 2,4,6-trinitrotoluene (TNT) using one-pot synthesis of silver nanoparticles via biosynthetic route using natural precursor extracts of clove and pepper. The biosynthesized silver nanoparticles (bio Ag Nps) have been characterized using UV-vis spectroscopy, scanning electron microscopy and atomic force microscopy. SERS studies conducted using bio Ag Nps on different water insoluble analytes, such as CL-20 and TNT, lead to SERS signals at concentration levels of 400 pM. The experimental findings have been corroborated with density functional computational results, electrostatic surface potential calculations, Fukui functions and potential measurements.

Efecto de concentraciones de aceite de algodón sobre la viabilidad, patogenicidad, estabilidad de la cepa CB-32 de Beauveria bassiana (Bals y vuils)

En Nicaragua, Plutella xylostella es la plaga que causa mayores daños al cultivo de repollo (Brassica oleracea) lo que implica una gran inversión en el control de la misma. Para contribuir a la búsqueda de alternativas para el Manejo integrado de esta plaga se realizó este estudio en las instalaciones del Centro Nacional de Protección Vegetal (CENAPROVE) y en la Universidad Nacional Agraria durante el periodo comprendido entre Febrero 1991 y Febrero 1992. Se evaluó la Cepa CB-32 del hongo entomopatógeno Beauveria bassiana (Bals & Vuils) en 6 formulaciones conteniendo 0%, 2%, 4%, 6%. 8% y 10% de aceite de algodón en agua sobre larvas del segundo instar de P. xylostella. La concentración de conidias en las formulaciones fué de 3.35x108 En un rango de tiempo de 14-30 horas después de la inoculación en PDA se distinguieron con un mayor porcentaje de germinación de conidias las formulaciones con O y 2% de aceite de algodón. Las mismas demostraron mayor sedimentación reportando 0.2 y 0.5 ml seis horas después de ser sometidas a reposo. Para la evaluación del efecto de la radiación solar sobre las conidias de B. bassiana se realizó un análisis de varianza y pruebas de Tukey con un 95% de confianza, las respaldan que las formulaciones pueden separarse en cuatro categorías estadísticas diferentes de las cuales en primer lugar tenemos las formulaciones con O y 2% de aceite que presentan el mayor porcentaje de germinación de conidias expuestas a 24 horas de radiación solar (86.61% y 80.36%) respectivamente. A la variable patogenicidad de las conidias de B. bassiana en huésped de Plutella xylostella se efectúo un análisis de varianza y prueba de Tuckey y resulto que las formulaciones pueden clasificarse en 3 categorías estadísticas, sobresaliendo la patogenicidad de las conidias de las formulaciones con O y 2% de aceite reportando 95 y 80% respectivamente. El tiempo letal para las formulaciones no varió provocando la mortalidad dos días después de la inoculación de las larvas por el método de inmersión.

Reduction in Chaetoceros populations by furanace

One of the most promising prophylactic agents being tested to control Penaeus monodon larval diseases is furanace (6-hydroxymethyl-2 2(5-nitro-2-furyl) vinyl pyridine). To evaluate further its suitability as a chemotherapeutic agent, its effects on the population growth of Chaetoceros calcitrans, the diatom used as feed for the zoeal stages, was examined. Chaetoceros populations of uniform density (initial density in all runs: 130-141x10 SUP-3 cells /ml) were placed in nine white, circular (382 sq cm), plastic basins. The physio-chemical characteristics of the culture water were as follows: salinity, 28 . 5-30 . 0 ppt; pH, 8 . 62-8 . 72; temperature, 23-25 . 5 degree C; dissolved oxygen, 7 . 1-9 . 3 ppm; nitrate, 0 . 03-0 . 07 ppm; and ammonia, 0 . 005-0 . 03 ppm. Preweighed furanace granules were dissolved in the culture water, with resulting concentrations of 1 and 2 mg/l (3 replicates each). A set of replicates without furanace served as the control. Population counts of the diatom were taken after 2, 4, 6, 8, and 10 hr exposures. After 4 hr, the population decreased in all three levels. The population in 2 mg/l furanace showed the lowest count and that in control the highest. The population means are not statistically different from one another. The results of the study show that the furanace causes reductions in Chaetoceros population at all durations of exposure.