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- Item1,1,2,2-Tetra-kis(1,3-benzoxazol-2-yl)ethene(2011) Hagos T.K.; Nogai S.D.; Dobrzaska L.; Cronje S.; Raubenheimer H.G.The title compound, C30H16N4O4, reveals crystallographic and mol-ecular symmetry and accordingly the asymmetric unit comprises one half-molecule. The dihedral angle between the planes of the two geminal benzoxazole rings is 74.39 (5)°. The packing features weak C - H⋯N and π-π interactions [centroid-centroid distance = 3.652 (1) Å].
- Item1,1,2,2-Tetrakis(1,3-benzothiazol-2-yl)ethene chloroform disolvate(2010) Hagos T.K.; Nogai S.D.; Dobrzanska L.; Cronje S.; Raubenheimer H.G.The asymmetric unit of the title solvate, C30H 16N4S4·2CHCl3, contains one half-molecule of tetrakis(2-benzothiazolyl)ethene, the complete molecule being generated by inversion symmetry, and one molecule of chloroform. Pairs of the benzothiazole rings attached to the same carbon atom are almost perpendicular to each other, with an angle between planes of 85.74 (4)°. In the crystal, weak C-H⋯N and C-H⋯Cl interactions generate a three-dimensional network.
- Item1000-580Ma crustal evolution in the northern Arabian-Nubian Shield revealed by U-Pb-Hf of detrital zircons from late Neoproterozoic sediments (Elat area, Israel)(2012) Morag N.; Avigad D.; Gerdes A.; Harlavan Y.The final stages in the evolution of the Arabian-Nubian Shield (ANS) during the late Neoproterozoic include the deposition of sub-aerial volcano-sedimentary sequence above exhumed deep-seated plutonic-metamorphic rocks. In southern Israel the sediments in this sequence, known collectively as the Elat conglomerate unit, consist primarily of immature polymictic conglomerates whose composition closely reflects their underlying basement. U-Pb dating and Hf isotopic analysis of single zircons from two samples of the Elat conglomerate is used here to gain a complementary perspective on crustal evolution processes in the northern ANS. The U-Pb age spectra of the detrital zircons bear evidence for two major magmatic cycles separated by a lull; early island-arc magmatism occurred at 880-760Ma and peaked at ∼800Ma, whereas post-collisional granitoids and volcanics invaded the amalgamated arc crust between 660 and 580Ma and peaked at 610-630Ma. Integration with previously published data from Sinai suggests the aforementioned igneous cycles and the intervening lull are of regional significance. Although island-arc igneous activity in the ANS ranged mostly between 880 and 760Ma, the occurrence of detrital zircons with strongly positive e{open} Hf(t) values and U-Pb ages of up to 1.0Ga in the Elat conglomerate suggests that island-arc magmatism in the northern ANS started in the early Tonian, earlier than previously recognized. The youngest zircons in the Elat conglomerate constrain its deposition age to ∼580. Ma. No younger U-Pb zircon ages were obtained for crystalline rocks in this region, our data thus indicates that 580. Ma marks the cessation of igneous activity in the northern ANS. The great majority of detrital zircons in the Elat conglomerate display positive e{open} Hf(t) values, in line with the overall juvenile character of the Shield. Nonetheless, the relatively wide range of e{open} Hf(t) values in zircons representing island-arc magmatism (between +3.6 and +11.6), and the presence of zircons with pre-Neoproterozoic ages and/or negative e{open} Hf(t) values, suggest some contamination of the arc magmas by an older crustal component. The e{open} Hf(t) values in zircons representing the younger, post-collisional magmas are all positive (between +4.9 and 9.2) and resemble those in the preceding arc-derived zircons. This feature is consistent with both reworking of mafic island-arc crust and contribution from mantle-derived melts during the post-collisional stage. Thus, it cannot be deciphered whether the 1000-580Ma igneous activity in the northern ANS represents continuous juvenile crustal addition from the mantle, or subsequent recycling of early-formed arc crust during a later post-collisional phase. © 2012 Elsevier B.V.
- Item16α-Hydroxyprogesterone: Origin, biosynthesis and receptor interaction(2011) Storbeck K.-H.; Swart P.; Africander D.; Conradie R.; Louw R.; Swart A.C.
- Item195Pt NMR isotopologue and isotopomer distributions of [PtCln(H2O)6 - N]4 - n (n = 6,5,4) species as a fingerprint for unambiguous assignment of isotopic stereoisomers(2008) Gerber W.J.; Murray P.; Koch K.R.A detailed analysis of the 35Cl/37Cl isotope shifts induced in the 128.8 MHz 195Pt NMR resonances of [PtCl n(H2O)6 - n]4 - n complexes (n = 6,5,4) in acidic solution at 293 K, shows that the unique isotopologue and isotopomer distribution displayed by the resolved 195Pt resonances, serve as a fingerprint for the unambiguous identification and assignment of the isotopic stereoisomers of [PtCl5(H2O)]- and cis/trans-[PtCl4(H2O)2]. © 2008 The Royal Society of Chemistry.
- Item1H-MRS in autism spectrum disorders: A systematic meta-analysis(2012) Ipser J.C.; Syal S.; Bentley J.; Adnams C.M.; Steyn B.; Stein D.J.We conducted a systematic review and metaanalysis of proton magnetic resonance spectroscopy (1HMRS) studies comparing autism spectrum disorder (ASD) patients with healthy controls, with the aim of profiling ASD-associated changes in the metabolites N-acetylaspartate (NAA) and Creatine (Cr). Meta-regression models of NAA and Cr levels were employed, using data from 20 eligible studies (N0852), to investigate age-dependent differences in both global brain and region-specific metabolite levels, while controlling for measurementmethod (Cr-ratio versus absolute concentrations). Decreased NAA concentrations that were specific to children were found for whole-brain grey and white matter. In addition, a significant decrease in NAA was evident across age categories in the parietal cortex, the cerebellum, and the anterior cingulate cortex. Higher levels of Cr were observed for ASD adults than children in global grey matter, with specific increases for adults in the temporal lobe and decreased Cr in the occipital lobe in children. No differences were found for either NAA or Cr in the frontal lobes. These data provide some evidence that ASD is characterized by age-dependent fluctuations in metabolite levels across the whole brain and at the level of specific regions thought to underlie ASD-associated behavioural and affective deficits. Differences in Cr as a function of age and brain region suggests caution in the interpretation of Cr-based ratio measures of metabolites. Despite efforts to control for sources of heterogeneity, considerable variability in metabolite levels was observed in frontal and temporal regions, warranting further investigation. © Springer Science+Business Media, LLC 2012.
- Item(2051) Proposal to conserve the name Talaromyces over Lasioderma (Ascomycota)(2012) Seifert K.A.; Frisvad J.C.; Houbraken J.; Llimona X.; Peterson S.W.; Samson R.A.; Visagie C.M.[No abstract available]
- Item(2E)-N,N′-bis(pyridin-4-ylmethyl)but-2-enediamide dihydrate(2005) Lloyd G.O.In the centrosymmetric title compound, C16H16N 4O2·2H2O, the water molecules donate two hydrogen bonds and accept one each, with O⋯O and O⋯N distances of 2.7498 (13) and 2.8152 (13) Å, respectively, and with an N⋯O distance of 2.7368 (13) Å. In the crystal structure, molecular channels are formed which are are occupied by water. © 2005 International Union of Crystallography Printed in Great Britain - all rights reserved.
- Item[(3-Methylphenyl)(triphenylphosphonio)-methanide-κC] triphenylphosphorane}-(pentafluorophenyl-κC)gold(I) diethyl ether solvate(2009) Strasser C.E.; Coetzee K.; Cronje S.; Raubenheimer H.G.The metal atom in the title ylid-gold(I) adduct, [Au(C6F 5)(C26H23P)]·C4H 10O, exists in a linear coordination environment [C- Au- C = 174.1 (2)°]. The mol-ecule has a short intra-molecular contact involving an aromatic H atom (Au⋯H = 2.64 Å); two adjacent mol-ecules are linked by an Au⋯Hylid inter-action (Au⋯H = 3.14 Å).
- Item3230-3200 Ma post-orogenic extension and mid-crustal magmatism along the southeastern margin of the Barberton Greenstone Belt, South Africa(2011) Lana C.; Buick I.; Stevens G.; Rossouw R.; De Wet W.The Barberton Granitoid-Greenstone Terrain (South Africa) preserves a complex and protracted evolution involving several events of magmatism and terrain accretion along convergent tectonic boundaries. Recent studies propose that the main period of tectonic accretion and arc-related magmatism is linked to a system of divergent subduction zones above which voluminous TTG magmas were emplaced between ca. 3236 and 3227 Ma. Our structural and LA-ICP-MS U-Pb geochronology study along the southeastern margin of the Barberton Greenstone Belt (BGB) ties the waning stages of this TTG magmatism to a short (ca <30 Ma) period of mid-crustal extension, between 3228 and 3205 Ma. We document a major NE-trending detachment that juxtaposed upper sequences (Moodies Group clastic sediments) against mid-crustal 3418 ± 10 Ma amphibolite-facies rocks of the base of the greenstone belt (Onverwacht Group rocks). Several granodiorite bodies - intruded along this detachment - contain well-preserved (syn- and post-magmatic) fabrics that are demonstrably related to extensional shearing and exhumation. Field observations and U-Pb zircon data from these granitoids are consistent with the deformation taking place at 3228 ± 10 Ma - contemporaneous with the voluminous (3236-3227 Ma) TTG magmatism in the northwestern margin of the BGB. The timing of the granodiorite emplacement also constrains a minimum age for the deposition of the Moodies Group clastic sediments, which for much of the southern and southeastern parts of the BGB must have happened before ca. 3228 Ma. 3205 ± 9 Ma subvolcanic dykes intruded into the granodiorite complex indicate that the period of exhumation and cooling of the crystalline rocks along the extensional detachment was relatively short (<30 Ma), between 3228 and 3205 Ma. Our observations combined with previously published structural data from the northwestern and southern margin of the belt suggest that the main mechanism of large-scale infolding of the supracrustal strata was shortly followed by the extension-related magmatism and subsequent, solid-state diapiric movement of the arc-related plutons. © 2011 Elsevier Ltd.
- Item35Cl/ 37Cl isotope effects in 103Rh NMR of [RhCl n(H 2O) 6-n] 3-n complex anions in hydrochloric acid solution as a unique 'NMR finger-print' for unambiguous speciation(2012) Geswindt T.E.; Gerber W.J.; Brand D.J.; Koch K.R.A detailed analysis of the 35Cl/ 37Cl isotope effects observed in the 19.11MHz 103Rh NMR resonances of [RhCl n(H 2O) 6-n] 3-n complexes (n=3-6) in acidic solution at 292.1K, shows that the 'fine structure' of each 103Rh resonance can be understood in terms of the unique isotopologue and in certain instances the isotopomer distribution in each complex. These 35Cl/ 37Cl isotope effects in the 103Rh NMR resonance of the [Rh 35/37Cl 6] 3- species manifest only as a result of the statistically expected 35Cl/ 37Cl isotopologues, whereas for the aquated species such as for example [Rh 35/37Cl 5(H 2O)] 2-, cis-[Rh 35/37Cl 4(H 2O) 2] - as well as the mer-[Rh 35/37Cl 3(H 2O) 3] complexes, additional fine-structure due to the various possible isotopomers within each class of isotopologues, is visible. Of interest is the possibility of the direct identification of stereoisomers cis-[RhCl 4(H 2O) 2] -, trans-[RhCl 4(H 2O) 2] -, fac-[RhCl 3(H 2O) 3] and mer-[RhCl 3(H 2O) 3] based on the 103Rh NMR line shape, other than on the basis of their very similar δ( 103Rh) chemical shift. The 103Rh NMR resonance structure thus serves as a novel and unique 'NMR-fingerprint' leading to the unambiguous assignment of [RhCl n(H 2O) 6-n] 3-n complexes (n=3-6), without reliance on accurate δ( 103Rh) chemical shifts. © 2012 Elsevier B.V.
- Item4,4′-Oxydibenzoic acid(2007) Potts S.; Bredenkamp M.W.; Gertenbach J.-A.In the title compound, C14H10O5, each carboxyl group is coplanar with the attached aromatic ring. The dihedral angle between these planes is 72.56 (5)°. The carboxyl groups are linked by a pair of centrosymmetric O - H⋯O hydrogen bonds, creating a zigzag chain along the [2 1] direction. © International Union of Crystallography 2007.
- Item4-Bromo-N-(diisopropoxyphosphor-yl)benzamide(2009) Strasser C.E.; Sheng X.; Safin D.A.; Raubenheimer H.G.; Luckay R.C.In the title compound, C13H19BrNO4P, the crystal structure is stabilized by inter-molecular N- H⋯O hydrogen bonds between the phosphoryl O atom and the amide N atom which link the mol-ecules into centrosymmetric dimers. These dimers are further packed into stacks along the c axis by inter-molecular C- H⋯O and C- H⋯π inter-actions.
- Item45 degree ASSUMPTION IN PARALLEL PLATE POLARISER DESIGN.(1986) Cloete J.H.The model underlying the standard parallel-plate polariser design equations is analysed using diffraction theory. It is shown that the usual 45 degree inclination angle yields an elliptically polarised field on axis with approximately 1 dB axial ratio at the design frequency, instead of the desired circular polarisation.
- Item7-Vinyldecyl acetate, novel inhibitor of pheromonal attraction in the false codling moth, Cryptophlebia leucotreta(1990) Burger B.V.; Le Roux M.; Mackenroth W.M.; Spies H.S.C.; Hofmeyr J.H.It was found that 7-vinyldecyl acetate, a by-product of the synthesis of one of the constituents of the sex attractant of the false codling moth, Cryptophlebia leucotreta, effectively disrupts the attraction of male moths to virgin females or to synthetic lures.
- ItemA bitemark case with a twist(1994) Thompson I.O.C.; Phillips V.M.This is a case report in which the bite patterns of two suspects were compared to a bitemark on the breast of a murder victim. Each suspect had sufficient concordant features to have been found guilty of producing the bitemark. The irony in this case is that the bitemark was not inflicted by the murderer. The admissibility of bitemarks as evidence in a court of law is still questionable. The present case illustrates the dilemma that may arise when bitemarks are evaluated.
- ItemA broader model for C 4 photosynthesis evolution in plants inferred from the goosefoot family (chenopodiaceae s.s.)(2012) Kadereit, G.; Ackerly, D.; Pirie, M. D.
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- ItemA caries preventive programme for Robertson school children--baseline data.(1991) Louw A.J.; Carstens I.L.; Hartshorne J.E.This study describes the baseline caries experience of a cohort school children in the Robertson area who were selected to take part in a longterm school-based preventive programme. On the whole baseline DMFT values for the various age groups did not differ significantly except for the 13-year-olds at Vergesig who had significantly higher values than those obtained at the other two schools. The D-component predominated with a moderate M-component and no filled teeth. The teeth at risk for the respective age groups did not differ significantly between the schools. The frequency of caries experience decreased from the molars to the central incisors except for the canines which were least vulnerable. The DMFT values were high and warrant the search for the most suitable preventive measures to facilitate reduction towards the WHO goal of 3 for 12-year-olds by the year 2000.
- ItemA case for the use of Q-methodology in disability research: Lessons learned from a training workshop(2011) McKenzie J.; Braswell B.; Jelsma J.; Naidoo N.