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Mechanical properties such as thickness, hardness, and wear resistance of an anodic oxide layer on aluminum must be high enough for industrial purposes. Due to burning phenomenon, hardness and wear resistance of anodic oxide layer decrease as the thickness of the layer increases. These properties of oxide layer fabricated by regular anodizing on aluminum in mixed sulfuric-oxalic acid electrolyte were optimized using pulsed currents. For this purpose, four variable response surface design (duty cycle, frequency, maximum and minimum current densities) was utilized. Desirability function was used to maximize thickness, microhardness and wear resistance of the anodic oxide layer. Wear resistance of the layer was measured by means of ‘pin on disk’ method according to ASTM G89 standard. The determined optimal anodizing conditions were: duty cycle = 65%, frequency = 326 Hz, i max = 3.5 and i min = 0.5 A/dm 2 , while the corresponding estimated responses values were 170 μm, 526 Hv 0.1 and 2.12 × 10 − 7 g/N.m for thickness, microhardness, and wear rate, respectively. Frictional behavior of optimized pulsed, and direct current anodic oxide layers was discussed in terms of friction coefficient and examination of worn surfaces. [ABSTRACT FROM AUTHOR]

Background and Objectives: Group B Streptococci (GBS) is a major cause of neonatal and maternal infections. The aim of this study was to determine the serotype distribution and antibiotic resistance profile of GBS strains isolated from pregnant women in Ardabil. Materials and Methods: Antibiotic resistance of 56 GBS isolates was investigated using E-test strips and disk-diffusion method. Serotyping was performed using capsular antiserum. Results: The results of MIC tests showed all isolates were susceptible to ampicillin, vancomycin and penicillin. One isolate (1.7%) showed reduced susceptibility pattern to penicillin (MIC; 0.25 µg/ml). There were 3 (5.3%) isolates semi-sensitive (0.25-1 µg/ml) to erythromycin (2; 0.5 µg/ml and 1; 0.38 µg/ml) and 2 (3.5%) isolates to clindamycin (1; 0.5 µg/ml, 1; 0.38 µg/ml). Additionally, 2 (3.5%) isolates were resistant to clindamycin (1; 16 µg/ml, 1; 2 µg/ml). According to the disk diffusion test, 47 (83.9%), 8 (14.2%) and 7 (12.5%) isolates were resistant to Co-trimoxazole, ciprofloxacin and ceftriaxone respectively. Serotypes V (19.6%), II (12.5%) and IV (12.5%) were the most frequent followed by serotypes III (10.7%) and VI (10.7%), Ib (8.9%), Ia (7/1%), VII (5/3%) and VIII (5/3%); 7.1% of strains were nontypeable. Conclusions: In this study, most isolates were sensitive to common antibiotics, but increased resistance to other antibiotics indicates the importance of monitoring of antibiotic resistance in group B streptococci over time. [ABSTRACT FROM AUTHOR]

New derivatives of 2-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4(3H) ones and 3-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-2,4(1H,3H) diones have been prepared by base catalyzed cyclocondensation of ethyl-3-aminothieno[3,2-b]pyridine-2-carboxylate with aryl nitriles and aryl- or alkyl isocyanates respectively. [ABSTRACT FROM AUTHOR]

The article discusses the need for statutory change to the right to terminate residential leases in Florida. The author points out that the development of consumer rights in the context of landlord-tenant transactions over the past 100 years has not harmed the residential rental industry. He also believes that development of tenants rights in the renewal of leases might actually benefit landlords by making their properties safer, more secure and more valuable.

The article discusses the activities of the Florida Bar Grievance Mediation and Fee Arbitration Committee.

In this paper, based on dual-energy broad beam gamma ray attenuation technique (using two transmission 1-inch NaI detectors and a dual-energy gamma ray source), an artificial neural network (ANN) model was used in order to predict the volume fraction of gas, oil and water in three-phase flows independent of the flow regime. A multilayer perceptron (MLP) neural network was used for developing the ANN model in MATLAB 8.1.0.604 software. The input parameters of the MLP model were registered counts under first and second full energy peaks of the both transmission NaI detectors, and the outputs were gas and oil percentage. The volume fractions were obtained precisely independent of flow regime using the presented model. Mean absolute error of the presented model was less than 2.24%. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article “Tracking Down Anonymous Internet Abusers: Who Is John Doe?" published in the November 2011 issue.

A new route for the synthesis of pyrazolo[4,3-e][1,2,4]triazolo[4,3-a]pyrimidine-4(5H)-imines has been delineated through heterocyclization of suitably functionalized pyrazoles with phenylisothiocyanate followed by methylation, nucleophilic displacement with hydrazine, and finally cyclocondensation with orthoesters. [ABSTRACT FROM AUTHOR]

In this study, the effect of electrophoretic voltage changes on Ni-AlO nano-composite coating via two step process electrophoretic, and electrochemically on 1100 Al substrate on morphology, corrosion and wear behaviour were studied. In the first step of deposition for determining the optimum amount of Teri Ethanol Amin activator in electrophoretic suspension Transmission Electron Microscopy (TEM) was used. The amount of alumina particles, Nickel ions in the coating and morphology were studied by Energy-dispersive X-ray spectroscopy (EDX) and Field-Emission Electron Microscopy (FESEM). Nanoparticles distribute more homogenous in deposit within using 40 V voltage. Corrosion behaviour of coating was investigated by polarization technique in 3.5 wt % NaCl which shows a decrease in corrosion current from 13.7 μA/cm to 1.46 μA/cm versus bare sample. [ABSTRACT FROM AUTHOR]

Nine different β-thioxoketones of general formula R1C(vO)CH2C(vS)R2 (R1 = C6H5, R2 = C6H5 L1; R1 = C6H5, R2 = p-CF3C6H4 L2; R1 = p-MeOC6H4, R2 = C6H5 L3; R1 = p-MeOC6H4, R2 = p-CF3C6H4 L4; R1 = C5H4N, R2 = C6H5 L5; R1 = p-IC6H4, R2 = C6H5 L6; R1 = C6H5, R2 = p-IC6H4 L7; R1 = C6H5, R2 = C10H7 L8 and R1 = CH3, R2 = C6H5 L9) and their tris-substituted bismuth(III) complexes having the general formula [Bi{R1C(vO)CHC(vS)R2}3] were synthesised and fully characterised. The solid state structure of [Bi{C5H4NC(vO)CHC(vS)C6H5}3] B5 was determined by crystallography and revealed that the three β-thioxoketonato ligands are bound to bismuth(III) centre in a bidentate fashion through O and S atoms. The bismuth(III) complexes and the corresponding thioxoketones were assessed for their activity against H. pylori. All of the bismuth(III) complexes were highly active against H. pylori having a MIC of greater than or equal to 3.125 μg mL-1, while the free acids were essentially not toxic to the bacteria. The anti-leishmanial activity of all the bismuth(III) β-thioxoketonates and the corresponding free acids were assessed against L. major promastigotes. The toxicity towards human fibroblast cells was also assessed. All of the free β-thioxoketones were selectively toxic to the L. major promastigotes displaying some potential as anti-leishmanial agents. Among these [C6H5C(vO)CH2C(vS)C6H5] L1 and [C5H4NC(vO)CH2C(vS)C4H5] L5 showed comparable activity to that of Amphotericin B, killing about 80% of the L. major promastigotes at a concentration of 25 μM (6.0 μg mL-1). The bismuth(III) β-thioxoketonate complexes were toxic to both the L. major promastigotes and fibroblast cells at high concentrations, but gave no improvement in anti-leishmanial activity over the free β-thioxoketones. [ABSTRACT FROM AUTHOR]

Two new thiocarboxylic acids, p-bromothiobenzoic BTA and thionaphthoic acid TNA, and five new homo- and heteroleptic bismuth(III) compounds derived from thiocarboxylic acids: [Bi{S(C = O)C[sub 6]H[sub 4]Br}[sub 3] 1, [PhBi{S(C = O) C[sub 6]H[sub 4]Br}[sub 2]] 2, [Bi{S(C = O)C[sub 10]H[sub 7]}[sub 3]] 3, [PhBi{S(C = O)C[sub 1]0H[sub 7]}[sub 2]] 4, and [Ph[sub 2]Bi{S(C = O)C[sub 10]H[sub 7]}] 5 were synthesised and fully characterised. The solid-state structure of complex [PhBi{S(C = O)C[sub 6]H[sub 4]Br}[sub 2]] 2 was confirmed by X-ray crystallography. In complex 2, the two thiocarboxylate ligands are coordinated to the bismuth(III) centre in a didentate fashion, forming a distorted octahedral geometry in which the phenyl group and the lone pair are oriented axial to the plane formed by the two thiocarboxylate ligands. Long-range Bi-S interactions (3.54 ©) link these monomeric units to form a one-dimensional polymer. These compounds, in addition to six previously synthesised complexes: [Bi{SC( = O)C[sub 6]H[sub 5]}[sub 3]] 6, [PhBi{SC( = O)C[sub 6]H[sub 5]}[sub 2]] 7, [Ph[sub 2]Bi{SC( = O)C[sub 6]H[sub 5]}] 8, [Bi{SC( = O)C[sub 6]H[sub 4]NO[sub 2]}[sub 3]] 9, [PhBi{SC( = O)C[sub 6]H[sub 4]NO[sub 2]}[sub 2]] 10, and [PhBi{SC( = O)C[sub 6]H[sub 4]SO[sub 3]}] 11, and the thiocarboxylic acids themselves, were assessed for their in vitro activity against Leishmania major promastigotes, and for general toxicity against human fibroblast cells. The thiocarboxylic acids, with the exception of thiobenzoic acid and sulfothiobenzoic acid, were toxicto both L. major parasites and the mammalian cells at high concentrations of 50-100 mM. The bismuth(III) thiocarboxylate derivatives proved to be more active than the corresponding acids. Among these, the heteroleptic phenyl-substituted bismuth(III) complexes 2, 4, 5, and 7 were highly active, showing IC50 (half maximal inhibitory concentration) values ranging from 0.39 to 4.69 ΜM, and a clear ligand dependence on activity. [ABSTRACT FROM AUTHOR]

Abstract: Eight new homo-and hetero-leptic bismuth(III) complexes and two new polynuclear bismuth(III) oxido clusters derived from acetosulfame (AceH) and cyclamic acid (CycH2) have been synthesised and characterised. Complexes, [Ph2Bi(Ace)] 1, [Bi(Ace)3] 2, [PhBi(Ace)2] 3, [Bi(CycH)3] 6, [Ph2Bi(CycH)] 7 and [PhBi(CycH)2] 8 were synthesised by treating BiPh3 with the appropriate acid in 1:1, 1:2 and 1:3 stoichiometric ratios under solvent-free or solvent-mediated conditions. Complex 4, [Bi(OH)(Ace)2], was obtained from the hydrolysis of 3. [Bi2(Cyc)3] 9 was obtained from the reaction of cyclamic acid with (Bi(OtBu)3) in a 3:2 ratio under inert conditions. The polynuclear bismuth oxido clusters, [Bi50O64(Ace)22(H2O)10] 5 and [Bi38O45(CycH)24(H2O)14] 10 were obtained using Bi2O3 under sonication in water and their composition confirmed through elemental and thermogravimetric analyses. The DMSO soluble complexes, 1, 2, 4, 5, 6, 7 and 9, were all assessed for their in-vitro activity against three strains of H. pylori (251, 26695 and B128). All compounds gave an MIC value of 6.25 μg/mL, indicating that bactericidal activity is insensitive to increased substitution by acetosulfamate or cyclamate at the Bi(III) centre. [Copyright &y& Elsevier]

Two new substituted thiobenzoic acids, m-nitrothiobenzoic and m-sulfothiobenzoic acid, and six (four new) homo- and heteroleptic bismuth(iii) compounds derived from thiobenzoic acid and substituted thiobenzoic acid have been synthesised and fully characterised using both solvent free and solvent mediated methods; Bi(SC(=O)C[sub 6]H[sub 5])[sub 3] (3), PhBi(SC(=O)C[sub 6]H[sub 5])[sub 2] (4), Ph[sub 2]Bi(SC(=O)C[sub 6]H[sub 5]) (5), Bi(SC(=O)C[sub 6]H[sub 4]-m-NO[sub 2])[sub 3] (6), PhBi(SC(=O)C[sub 6]H[sub 4]-m-NO[sub 2])[sub 2] (7), and PhBi(SC(=O)C[sub 6]H[sub 4]-m-SO[sub 3]) (8). The solid-state structures of the previously reported Bi(SC(=O)C[sub 6]H[sub 5])[sub 3] (3) and PhBi(SC(=O)]C[sub 6]H[sub 5])[sub 2] (4) complexes have now been confirmed by X-ray crystallography. In the solid-state complex 3 forms a column-like polymeric structure resembling stacked bowls through pyramidal intermolecular Bi-S[sub 3] bonds of distance 3.359 , providing a Bi(iii) centre with a nine coordinate environment. Complex 4 forms discrete tetrameric units cemented by long intermolecular Bi-S (3.774 ), Bi-O(= C) (3.030, 3.071 ) and Bi-C bonds (3.627 ). The complexes were assessed for their activity against three strains of Helicobacter pylori and all show a minimum inhibitory concentration of 6.25 μg mL[sup -1], indicating that the high level of bactericidal activity is insensitive to the degree of substitution at the Bi(iii) centre. Six homo- and heteroleptic bismuth(iii) thiobenzoates of form Ph[sub 3-n]BiL[sub n] (n = -3) have been synthesised by solvent-mediated and solvent-free methods. The structures of the compounds derived from thiobenzoic acid have been determined by X-ray crystallography. Bactericidal studies against three strains of Helicobacter pylori show a minimum inhibitory concentration of 6.25 μg mL[sup -1] for all compounds, indicating that the high activity is independent of ligand type and degree of substitution at the Bi(iii) centre. [ABSTRACT FROM AUTHOR]

Five bismuth(III) saccharinate and thiosaccharinate complexes, [Ph2Bi(sac)]∞1, [Bi(sac)3]n2, [Ph2Bi(tsac)]∞4, [PhBi(tsac)2]n5, [Bi(tsac)3]n6 (sacH = saccharin, tsacH = thiosaccharin), have been synthesized and fully characterized. The tendency for ligand redistribution in [Ph2Bi(sac)]∞ has been investigated in solution by NMR spectroscopy. The structures of [Ph2Bi(sac)]∞1 and [Ph2Bi(tsac)]∞4 have been confirmed by X-ray crystallography. In Ph2Bi(sac) the sac ligand is bound to a four-coordinate bismuth center via its imino nitrogen atom with an accompanying long-range Bi–O interaction. However, in the structure of [Ph2Bi(tsac)]∞ the ligand is σ-bound through the exocyclic sulfur atom, giving a thiolate complex, confirming the more thiophilic nature of bismuth(III). Both complexes consist of polymeric chain structures with formally four-coordinated bismuth atoms. The complexes were assessed for their activity against H. pylori. The activity is both ligand dependent and sensitive to the degree of ligand substitution. The saccharinate complexes, 1 and 2, show activity comparable with standard tris-carboxylato bismuth(III) compounds, 6.25 μg/mL, while the activity of the thiolato complexes, 4–6, increases dramatically on increasing the number of thiolate groups from one to three (range 50–6.25 μg/mL). Saccharin, thiosaccharin, and BiPh3 were found to be inactive. [ABSTRACT FROM AUTHOR]