bluuebunny/crossref_metadata_2025 huggingface dataset:
Developmental morphology of the flower of Anaphyllopsis americana and its relevance to our understanding of basal Araceae
Authors: Barabé Denis , Lacroix Christian
Published: December 2008

The inflorescence of Anaphyllopsis americana (Engler) A. Hay consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The unilocular ovary contains one ovule and bears a discoid stigma. The floral primordia are first initiated on the upper portion of the inflorescence. At an early stage during their development, the floral primordia have a circular shape. Two lateral tepals are initiated nearly simultaneously followed by two median tepals. After their initiation, each stamen is associated with a tepal of the same radius; the two lateral stamens are initiated first, directly opposite to the lateral tepals. The unilocular nature of the ovary is clearly visible during the early stages of development of the gynoecium. At dehiscence, anther wall raphides are present in anther locules and are mixed with pollen. The mode of floral development observed in Anaphyllopsis is similar to that reported for Anthurium jenmanii Engl. However, this similarity in mode of development may be linked to structural constraints rather than phylogenetic relationships. The presence of a few pentamerous flowers in the inflorescence of Anaphyllopsis suggests a possible relationship with Dracontium . This would be in accordance with recent molecular studies showing that Anaphyllopsis and Dracontium are closely related.
Does seed heteromorphism have different roles in the fitness of species with contrasting life history strategies?
Authors: Lerner Pamela D. , Bai Yuguang , Morici Ernesto F.A.
Published: December 2008

Punagrass ( Achnatherum brachychaetum (Godr.) Barkworth) and flechilla grande (Nassella clarazii (Ball) Barkworth) are perennial grasses native to Argentine grasslands, with contrasting life history strategies. Both species have seed heteromorphism, but punagrass is an invasive whereas flechilla is a climax species. Experiments were conducted to determine the relative contribution of chasmogamous (CH) seeds and cleistogamous (CL) seeds to growth and reproduction of the two species. CH progeny of punagrass grew and developed fast, but progeny of the largest CL seeds of the first node allocated more resources to the production of CH seeds. Growth and seed production of CH progeny of punagrass were enhanced by increasing nutrients, displaying adaptations to nutrient-rich environments. Thus, the slow-growing CL progeny may have potential to persist as a source of CH propagules until the creation of conditions favouring the less competitive CH progeny. Since CH progeny allocated more to CL seeds, but produced fewer CH seeds under low nutrient conditions, it is suggested that competitive environments would increase the production of CL seeds. Furthermore, when nutrients were abundant, punagrass allocated more to CH seeds. Under limiting nutrients, flechilla grande produced a few large CH seeds. The production of large seeds in flechilla grande may confer superior competitive ability to its progeny, but it may be disadvantageous under heavy grazing, which favours invasive species such as punagrass with both large CL seeds and many small CH seeds of high colonizing potential.
Paleomagnetism, U–Pb geochronology, and geochemistry of Marathon dykes, Superior Province, and comparison with the Fort Frances swarm
Authors: Buchan Kenneth L. , Halls Henry C. , Mortensen James K.
Published: December 2008

We report the first detailed study of the paleomagnetism, U–Pb geochronology and major element geochemistry of Paleoproterozoic north-trending Marathon dykes north of Lake Superior. The paleomagnetic and geochemical results demonstrate that Marathon dykes can be divided into two subsets, one of normal magnetic polarity, the other of reverse polarity. Normal and reverse Marathon paleomagnetic poles, at 43°N, 196°E (dm = 9°, dp = 7°, number of dykes N = 16) and 51°N, 175°E (dm = 9°, dp = 6°, N = 12), respectively, are statistically distinct and may indicate different ages of normal and reverse dyke emplacement, A U–Pb baddeleyite age of [Formula: see text] Ma has been obtained at a normally magnetized Marathon paleomagnetic site. The reversely magnetized Marathon dykes are undated, but have a paleopole rather close to that of the reversely magnetized [Formula: see text] Ma Fort Frances dykes and major element geochemical signatures as portrayed on Jensen plots that are identical to those of the Fort Frances swarm. Therefore, reverse Marathon and Fort Frances dykes could define a giant radiating dyke swarm focused south of Lake Superior, supporting models that associate these dykes with Paleoproterozoic rifting along the southern margin of the Superior Province. The Marathon and Fort Frances paleopoles continue a northwesterly trend in southern Superior Province paleopoles, which has recently been defined by results for [Formula: see text] Ma Senneterre dykes and 2167 ± 2 Ma Biscotasing dykes. This trend contrasts with previous widely used polar wander paths for the same period that young in the opposite direction and illustrates the importance of collaborative studies of paleomagnetism and U–Pb geochronology.
Energy-momentum of the Friedmann models in General Relativity and the teleparallel theory of gravity
Authors: Sharif M , Amir M Jamil
Published: December 2008

This paper is devoted to the evaluation of the energy-momentum density components for the Friedmann models. For this purpose, we have used Møller’s pseudotensor prescription in General Relativity and a certain energy-momentum density developed from Møller’s teleparallel formulation. We show that the energy density of the closed Friedmann universe vanishes on the spherical shell at the radius ρ = 2[Formula: see text]. This coincides with the earlier results available in the literature. We also discuss the energy of the flat and open models. A comparison shows a partial consistency between Møller’s pseudotensor for General Relativity and teleparallel theory. Further, we show that the results are independent of the free dimensionless coupling constant of the teleparallel gravity.PACS No.: 04.20.–q
Finite-temperature phase transition in ϕ6 potential
Authors: Widyan H
Published: December 2008

The temperature dependance of the action in thin-wall and thick-wall limits is obtained analytically for the ϕ6 scalar potential. The nature of the phase transition is investigated from the quantum tunnelling regime at low temperatures to the thermal hopping regime at high temperatures. It is first-order for the case of a thin wall while for the thick wall it is second- order. PACS Nos.: 10.10.Wx, 05.70.Fh, 10.10.Ef
Catalytic synthesis of carbon nanotubes from the decomposition of methane over a Ni–Co/La2O3 catalyst
Authors: Chen Long , Liu Haitao , Yang Keli , Wang Jiankang , Wang Xiaolai
Published: December 2008

The production of multi-walled carbon nanotubes (MWNTs) by the catalytic chemical vapour deposition (CCVD) method was examined over a series of Ni–Co/La2O3 catalysts with methane as the carbon source. The catalyst composition and the reaction conditions were optimized by analyzing the effluent gas with gas chromatography. Various techniques, such as X-ray diffraction (XRD), Transmission electron microscopy (TEM), Raman spectra, and Thermal gravimetric analysis (TGA) were used to characterize the catalysts and products. The results indicate that the unreduced catalyst 30Ni–10Co/La2O3 showed the highest activity for methane decomposition, and the highest carbon yield, being 624.2%, was obtained over this catalyst at 700 °C after 60 min of reaction with hydrogen as carrier gas. TGA results suggest that the purity of carbon nanotubes (CNTs) can reach up to 98 wt% after a single-step purification by hydrochloric acid.Key words: carbon nanotubes, catalytic chemical vapour deposition, methane decomposition, Ni–Co/La2O3 catalyst.
The synthesis and X-ray crystal structures of rare earth(III) perfluoroadipate complexes — Novel coordination polymers
Authors: Deacon Glen B , Elgersma Winfried , Harika Rita , Junk Peter C , Skelton Brian W , White Allan H
Published: December 2008

A representative series of polymeric hydrated lanthanoid perfluoroadipates [Ln2(pfad)3(H2O)n]·mH2O (Ln = La, Ce, Nd, Gd, Yb) has been prepared from the reaction of perfluoroadipic acid with either the appropriate lanthanoid oxide or Ce2(CO3)3 in water. X-ray crystal structures showed [Ln2(pfad)3(H2O)10]·4H2O (La, Nd) to be two-dimensional inorganic polymers, which contain nine-coordinate Ln atoms to which are attached five water molecules and four carboxylate oxygen atoms. Two pfad ligands bridge two Ln atoms through one carboxylate group, the other being free, whilst one pfad ligand bridges four Ln atoms in a µ4-(η1,η1/η1,η1) manner. In two-dimensional polymeric [Yb2(pfad)2(H2O)8](pfad)·6H2O, each eight-coordinate ytterbium atom has four water ligands and four carboxylate oxygen donor atoms. The two carboxylate ligands bind in a µ4-(η1,η1/η1,η1) manner, and there is one pfad counter-ion per two ytterbium atoms. These structures show features quite different from those of many lanthanoid adipate complexes [Ln2(ad)3(H2O)n]·mH2O, but there is no F-Ln coordination. From the reaction of [Nd2(pfad)3(H2O)10]·4H2O with benzene-1,2-disulfonic acid (H2bds), the mixed ligand complex [Nd2(bds)2(pfad)(H2O)8] was isolated. This is a one-dimensional polymer featuring Nd2(bds)2 units linked together by µ-η2,η2 pfad ligands. Each Nd atom is nine-coordinate with three sulfonate oxygen donors, two carboxylate oxygen atoms, and four water ligands, and the bds ligands bind in the new µ-η2(O,O′),η1(O′′) manner for Ln complexes. Surprisingly, [Na2pfad] was isolated unhydrated from water, the six-coordinate Na atoms being coordinated by four carboxylate oxygen atoms and two (C)-F atoms in an octahedral array. The ligands are duodecadentate, each –CF2CO2 unit binding to five different sodium ions through four oxygen and one α-F atom with the second α-F atom bound to a sodium ion in a OC(O)CF-Na chelate ring.Key words: rare earths, lanthanoid, X-ray crystal structures, adipates, carboxylates.
Alkyne adducts of paramagnetic and diamagnetic tripalladium clusters supported by dppm ligands
Authors: Cugnet Cyril , Molin Sophie Dal , Brevet David , Lucas Dominique , Mugnier Yves , Harvey Pierre D , Boeré René T
Published: December 2008

The unsaturated redox-active cluster [Pd3(dppm)3(CO)]n+ (n = 0,1, or 2) reacts with ethylene dicarboxylic esters and a variety of terminal acetylenes (but not PhC≡CPh) in all three charge states. In particular, the radical cations [Pd3(dppm)3(CO)(RC≡CR′)].+ can be produced by several routes: one-electron electrochemical reduction of the dication adducts, comproportionation of the neutral and dicationic adducts, as well as the direct complexation of alkyne to the known radical cation [Pd3(dppm)3(CO)].+. Compared with the latter, each of the adducts have significantly extended lifetimes and classify as persistent radicals in solution. The alkyne adducts have been characterized by voltammetry (cyclic and rotating disk electrode), by UV – vis titrations and by MALDI-TOF mass spectra from dithranol matrices. Isotropic solution EPR spectra of the adducts with R = R′ = MeOC(O) and EtOC(O), as well as those with R′ = H and R = C6H5, FC6H4, HC≡CC6H4, and EtO have been obtained. Full line shape fitting simulations demonstrate that all display coupling to six different 31P (I = 1/2) and to one to three 106Pd (I = 5/2) nuclei. The A(31P) values range from a low of 3.0 × 104 to a high of 180.5 × 104 cm–1; this variation is caused by changes in the contribution of P s orbitals to the SOMO resulting from structural distortions of the Pd3P6 core upon alkyne coordination.Key words: electrochemistry, redox state, electron paramagnetic resonance, catalytic model, palladium, bridging phosphine.
Synthesis and organic group transfer of organodiplatinum complex with a 1,2-bis(diphenylphosphino)ethane ligand
Authors: Komine Nobuyuki , Ishiwata Tomoko , Kasahara Jun-ya , Matsumoto Erino , Hirano Masafumi , Komiya Sanshiro
Published: December 2008

A series of homometallic alkyl- and phenyldinuclear complexes containing one platinum–platinum bond, (dppe)RPt–Pt(η5-Cp)(CO) (R = Me, Et, CH2CMe3, Ph), have been prepared by oxidative addition of the Pt–C bond of PtR(η5-Cp) to Pt(styrene)(dppe), and were characterized by spectroscopic methods and (or) X-ray structure analysis. The geometry at Pt with a dppe ligand is square planar, and the carbonyl and Cp ligand of the Pt(η5-Cp)(CO) moiety lie orthogonal to the coordination plane of former platinum. Competitive organic group transfer reactions along the Pt–Pt bond in these complexes took place to give PtR(η5-Cp)(CO) and PtR(η1-Cp)(dppe) on thermolysis. Alkyl or aryl transfer from Pt with a dppe ligand were enhanced by addition of olefin, whereas treatment with CO and tertiary phosphine ligands causes Cp transfer from Pt(η5-Cp)(CO).Key words: organoplatinum–platinum complex, organic group transfer.
Structural and spectroscopic studies of some adducts of silver(I) salts with ethylenethiourea
Authors: Bowmaker Graham A , Chaichit Narongsak , Pakawatchai Chaveng , Skelton Brian W , White Allan H
Published: December 2008

Syntheses, single crystal X-ray structural and spectroscopic characterizations are described for a variety of adducts of silver salts with ethylenethiourea (etu). Ag2SO4/etu (1:6) is isomorphous with its previously studied copper(I) counterpart, the [Ag(S-etu)3]+ species disposed with their silver atoms on crystallographic 3-axes, one of the two independent cations being slightly perturbed by a distant O-sulfate approach along that axis. In AgCl/etu (1:3), the silver atom is in a four-coordinate ClAgS3 environment, while AgNO3/etu (1:3) takes the form [(etu)2Ag(µ-S-etu)2Ag(etu)2](NO3)2. AgBr/etu (1:2) is binuclear [(etu)2Ag(µ-Br)2Ag(etu)2)], unlike its previously studied copper counterpart, which is [(etu)BrCu(µ-S-etu)2CuBr(etu)]. AgCl/etu (4:6) is an interesting ionic polymer [ClAg4(etu)6](∞|∞)Cl3, containing a novel one-dimensional polymeric cation. Bands in the far IR spectra of these compounds are assigned to v(AgS) and v(AgX) (X = halogen) modes, and a correlation between v(AgS) and the Ag–S bond length d(AgS) is established for silver complexes involving the etu ligand.Key words: silver, sulfur ligands, X-ray crystal structure, coordination chemistry, complexes.
Synthesis and structures of palladium(II) and platinum(II) complexes containing heterocyclic thiolate ligands formed by cycloaddition reactions of coordinated azides
Authors: Fleischer Angela , Roller Alexander , Arion Vladimir B , Keppler Bernhard K , Mohr Fabian
Published: December 2008

The phosphine-stabilized azido complexes [M(N3)2(PTA)2] (M = Pd, Pt; PTA = 1,3,5-triaza-7-phosphaadamantane) were prepared in high yields by a ligand exchange reaction from cis-[Pd(N3)2(tmeda)] and cis-[Pt(N3)2(cod)], respectively. The Pd and Pt complexes [M(N3)2(PTA)2] undergo cycloaddition reactions with various isothiocyanates to give complexes containing anionic, S-coordinated tetrazole-thiolate ligands of the type trans-[M(SCN4R)2(PTA)2] (M = Pd, Pt; R = Et, allyl, Me, Ph). The molecular structures of several of these derivatives were determined by X-ray crystallography.Key words: palladium, platinum, thiolate, heterocycle, azide, cycloaddition.
Dinuclear organoplatinum(II) complexes containingN-methylbenzamide
Authors: Crisp Michael G , Rendina Louis M
Published: December 2008

The preparation and characterization of cationic, dinuclear complexes of the type trans-[Pt(PPh3)2(σ-C6H4NHMe)-µ-L-Pt(PPh3)2(σ-C6H4NHMe)](OTf)2(L = 4,4′-bipyridine, 4,7-phenanthroline, 4,4′-dipyrazolylmethane, and 1,1′-diphenyl-4,4′-dipyrazolylmethane; OTf = trifluoromethanesulfonate (triflate)) containing two C3-N-methylbenzamide ligands are described. The key structural feature of the cationic complexes is the presence of two convergent amide groups that may allow for charge-assisted, H-bonding interactions in solution with suitable heteroaromatic guest molecules such as nucleobases.Key words: organoplatinum(II) complex, organometallic host, dinuclear complex, N-methylbenzamide.
Zinc and iron complexes of a helix-directing (1R,2R)-cyclohexyl salen ligand with phenanthryl sidearms
Authors: Wiznycia Alexander V , Desper John , Levy Christopher J
Published: December 2008

A symmetrical salen ligand is formed by the condensation of (1R,2R)-diaminocyclohexane with 4-hydroxy-3-phenanthrenecarboxaldehyde. Crystallographic characterization of the metal complexes (ZnII, FeII, and FeIII) show 1:1 mixtures of diastereomeric M and P helical molecules. ECD spectra of the ZnII complex combined with DFT simulations strongly suggest that the M conformation is dominant in solution. This is supported by 1H and 13C NMR data, which are consistent with a single species in solution.Key words: zinc, iron, ECD, DFT, salen complexes.
Synthesis and photophysical properties of naphthyl-, phenanthryl-, and pyrenyl-appended bis(pyridyl)triazine ligands and their Zn(II) and Ru(II) complexes1
Authors: Nastasi Francesco , Loiseau Frédérique , Campagna Sebastiano , Medlycott Elaine A , Santoni Marie-Pierre , Hanan Garry S
Published: December 2008

A family made of four bis(pyridyl)triazine ligands with appended aryl rings, including three fused aromatic rings, have been synthesized, and their corresponding homoleptic Ru(II) and Zn(II) complexes have been prepared and characterized by several means. The free ligands 2,4-di(2-pyridyl)-6-phenyl-1,3,5-triazine (L1); 2,4-di(2-pyridyl)-6-(1-naphthyl)-1,3,5-triazine (L2); 2,4-di(2-pyridyl)-6-(9-phenanthryl)-1,3,5-triazine (L3); and 2,4-di(2-pyridyl)-6-(1-pyrenyl)-1,3,5-triazine (L4) were formed in triazine ring-forming reactions from the reactions of the cyano-functionalized aromatic rings with LiNMe2 followed by the addition of 2 equiv. of 2-cyanopyridine. The metal complexes examined in this study are the homoleptic Ru(II) complexes Ru(L1)22+ (2a), Ru(L2)22+ (2b), Ru(L3)22+ (2c), and Ru(L4)22+ (2d) and Zn(II) complexes Zn(L1)22+ (3a), Zn(L2)22+ (3b), Zn(L3)22+ (3c), and Zn(L4)22+ (3d). Also, crystallographic data for the free ligands and Zn(II) and Ru(II) complexes have been obtained in some cases. The redox behaviour and absorption spectra of all the species have been investigated, together with the luminescence properties of the free ligands at room temperature in fluid solution and of the Ru(II) complexes both at room temperature in fluid solution and at 77 K in rigid matrix. The redox data indicate that the free ligands are reduced twice at relatively mild potentials (< –2.30 V vs. SCE), with the first reduction almost independent of the nature of the substituted aryl group. The UV absorption spectra of all the compounds are dominated by intense spin-allowed π–π* transitions mainly centered on the bis(pyridyl)triazine moiety; however, in L2–L4, moderately intense intraligand charge-transfer (ILCT) bands are also present. Such bands are red-shifted in the Zn(II) compounds, while they are obscured in the Ru(II) species by the more intense spin-allowed metal-to-ligand charge-transfer (MLCT) bands. The free ligands exhibit interesting emission properties, ranging from fluorescence from π–π* states to excimeric (in L4) and ILCT (in L2 and L3) emission. In the Ru(II) complexes, strong emission is found at 77 K from triplet MLCT states. For 2c and 2d, the emissive MLCT states are mixed with low-lying triplet ligand-centered states.Key words: triazine ligands, ruthenium complexes, zinc complexes, ILCT emission.
Chemical synthesis and structural studies of thiol-capped gold nanoparticles
Authors: Zhang Peng , Chu Andy Yuan-Chi , Sham Tsun-Kong , Yao Yun , Lee Shuit-Tong
Published: December 2008

We report the chemical synthesis and structural studies of thiol-capped Au nanoparticles (NPs) using extended X-ray absorption fine structures (EXAFS) and high-resolution transmission electron microscopy (HRTEM). Synthesis of Au NPs was conducted in one case in a toluene/water two-phase system using alkanethiols with varied hydrocarbon chain length (C6, C12, and C18), resulting in NPs of sizes ranging from 1.6 nm to 5.4 nm. Au L3-edge EXAFS reveals a systematical trend of the local structure of Au in the NPs when the Au/S ratio and chain-length of thiols are varied. In another synthesis, thiol-capped Au NPs were prepared on the surface of silicon nanowires, which act as both substrates and reducing agents. HRTEM reveals that not only spherical particles but also very small quasi-1D nanostructures of Au were formed. The formation and structure of these Au NPs was discussed in terms of ligand and template effect associated with the silicon nanowire substrates.Key words: thiol-capped Au nanoparticles, EXAFS, silicon nanowires, electroless deposition, quasi-1D Au nanostructures.
Bonding and structures of copper-aminopyridine complexes — High-resolution electron spectroscopy and ab initio calculations
Authors: Wang Xu , Yang Dong-Sheng
Published: December 2008

Copper complexes of x-aminopyridine (x = 2, 3, 4) were prepared in a laser vaporization supersonic molecular beam source and identified using laser photoionization time-of-flight mass spectrometry. These complexes were studied by pulsed-field ionization zero electron kinetic energy (ZEKE) spectroscopy and second-order Møller-Plesset perturbation theory. Three structures formed by Cu binding to the pyridine nitrogen (σα), the amino nitrogen (σβ), and the pyridine ring (π) were considered by the theoretical calculations, but only the σα structures with Cu binding to the pyridine nitrogen were confirmed by the spectroscopic measurements. Adiabatic ionization energies and metal-ligand and ligand-based vibrational frequencies of the σα complexes were measured from the ZEKE spectra, and the metal-ligand bond energies of the neutral and ionized complexes were predicted by the theory. The ionization energies of the Cu complexes are about 20 000 cm–1 lower than that of bare Cu atom. This ionization energy shift is the result of the stronger Cu+-ligand bonding because of the additional charge-dipole interaction in the ion. Although the three complexes are formed by Cu coordination to the pyridine nitrogen atom, the position of the amino group affects the metal-ligand bonding strengths in both neutral and ionized species. These effects include the structural resonance and hydrogen bonding in the neutral complexes and the electric dipole moment and bidentate bonding in the ions.Key words: photoelectron, PFI-ZEKE, ab initio, copper aminopyridine.
Dissecting out the effect of Ru-OAr bonding in a five-coordinate complex of ruthenium (II)
Authors: Monfette Sebastien , Duarte Silva João A , Gorelsky Serge I , Dalgarno Scott J , dos Santos Eduardo N , Araujo Maria H , Fogg Deryn E
Published: December 2008

Blue Ru(o-cat)(PPh3)3(5; o-cat = ortho-catecholate), obtained in 94% yield by reaction of RuCl2(PPh3)3(4) with dithallium catecholate, was characterized by NMR, MALDI-MS, IR, and single crystal X-ray analysis, and by a combined electronic spectroscopy and time-dependent density functional theory (TD-DFT) study. The frontier orbitals in 5 participate in a low-energy charge transfer excitation involving donation from the Ru-catecholate π bond (largely localized on catecholate) to a low-lying σ* orbital on Ru-PPh3(apical). The energy of this transition increases on binding a pyridine ligand in the sixth site.Key words: ruthenium aryloxide, catecholate, phosphine, electronic spectroscopy, time-dependent DFT.
Zinc halide oxazoline complexes — The quest for structural diversity
Authors: Gossage Robert A , Yadav Paras N , MacInnis Timothy D , Quail J Wilson , Decken Andreas
Published: December 2008

The synthesis and characterization of 14 ZnX2 (X = Cl or Br) complexes containing aryl-oxazoline (ox) ligands is reported. Eleven of these derivatives have been structurally elucidated in the solid state by single crystal X-ray diffraction methods. The ligands used are 2-(3-R-phenyl)-2-oxazoline (R = Cl or Me), 2-(4-R-phenyl)-2-oxazoline (R = Cl, F, Me or –OMe), and 2-(anisol-2-yl)-4,4-dimethyl-2-oxazoline (7a). All oxazolines, with the exception of 7a, lead to the formation of materials identified as ZnX2(ox)2 upon reaction with ZnX2. A distorted tetrahedral coordination motif around the Zn metal centre is displayed in nine examples that have been characterized by single crystal X-ray diffraction methods. In the case of ligand 7a, an unusual dimeric species (X-ray) of formula [ZnCl2(7a)]2 (7b) is formed upon reaction with ZnCl2. Compound 7b displays a rare (formally neutral) µ-(Cl)2-(Zn[L]Cl)2 (L = neutral donor ligand) unit in addition to secondary bonding interactions between the Zn centres and the O-atom of the –OMe group (Zn···O distance of ~2.56 Å). In contrast, reactions of 7a with ZnBr2 lead to the formation of a monomeric species containing a chelating molecule of 7a with binding through the oxazoline N-atom and the methoxy (Zn–O distance of ~2.14 Å) group, i.e., ZnBr2(7a-κ2N,OOMe). These complexes are discussed in terms of structurally related Zn species and some comment is made as to the direction to be explored within this series of materials that may lead to further unusual structural diversity.Key words: oxazoline, oxazole, zinc, X-ray crystal structure, coordination complex, Zn(II) halide.
Prevalence, Prognosis, and Implications of Isolated Minor Nonspecific ST-Segment and T-Wave Abnormalities in Older Adults
Authors: Kumar Anita , Prineas Ronald J. , Arnold Alice M. , Psaty Bruce M. , Furberg Curt D. , Robbins John , Lloyd-Jones Donald M.
Published: December 2008

Background—

The prevalence and prognostic significance of isolated minor nonspecific ST-segment and T-wave abnormalities (NSSTTAs) in older adults are poorly understood.

Methods and Results—

Cardiovascular Health Study participants free of both clinical cardiovascular disease and major ECG abnormalities were included. We examined the prospective association of isolated minor NSSTTAs (defined by Minnesota Codes 4–3, 4–4, 5–3, and 5–4) with total, cardiovascular, and coronary mortality and incident nonfatal myocardial infarction. Among 3224 participants (61.9% women; mean age, 72 years), 233 (7.2%) had isolated NSSTTAs at baseline. Covariates associated with isolated NSSTTAs included older age, nonwhite race (20.5% of blacks versus 4.8% of whites;
P
<0.001), diabetes, and higher blood pressure and body mass index but not the presence of subclinical cardiovascular disease. After 39 518 person-years of follow-up, the presence of isolated NSSTTAs was associated with significantly increased risk for coronary heart disease mortality (multivariable-adjusted hazards ratio, 1.76; 95% CI, 1.18 to 2.61) but not with incident nonfatal myocardial infarction (multivariable-adjusted hazards ratio, 0.71; 95% CI, 0.43 to 1.17). The association of isolated NSSTTAs with coronary death was independent of subclinical atherosclerosis and left ventricular mass measures. In secondary analyses, among those with cardiac death, there was a significantly higher rate of primary arrhythmic death (32.3% versus 15.4%;
P
=0.02) in participants with isolated NSSTTAs versus those without NSSTTAs.

Conclusions—

Isolated NSSTTAs are common in older Americans and are associated with significantly increased risk for coronary death. However, isolated NSSTTAs are not associated with incident nonfatal myocardial infarction, suggesting that they are associated particularly with increased risk for primary arrhythmic death.
Sex Differences in Medical Care and Early Death After Acute Myocardial Infarction
Authors: Jneid Hani , Fonarow Gregg C. , Cannon Christopher P. , Hernandez Adrian F. , Palacios Igor F. , Maree Andrew O. , Wells Quinn , Bozkurt Biykem , LaBresh Kenneth A. , Liang Li , Hong Yuling , Newby L. Kristin , Fletcher Gerald , Peterson Eric , Wexler Laura
Published: December 2008

Background—

Women receive less evidence-based medical care than men and have higher rates of death after acute myocardial infarction (AMI). It is unclear whether efforts undertaken to improve AMI care have mitigated these sex disparities in the current era.

Methods and Results—

Using the Get With the Guidelines–Coronary Artery Disease database, we examined sex differences in care processes and in-hospital death among 78 254 patients with AMI in 420 US hospitals from 2001 to 2006. Women were older, had more comorbidities, less often presented with ST-elevation myocardial infarction (STEMI), and had higher unadjusted in-hospital death (8.2% versus 5.7%;
P
<0.0001) than men. After multivariable adjustment, sex differences in in-hospital mortality rates were no longer observed in the overall AMI cohort (adjusted odds ratio [OR]=1.04; 95% CI, 0.99 to 1.10) but persisted among STEMI patients (10.2% versus 5.5%;
P
<0.0001; adjusted OR=1.12; 95% CI, 1.02 to 1.23). Compared with men, women were less likely to receive early aspirin treatment (adjusted OR=0.86; 95% CI, 0.81 to 0.90), early β-blocker treatment (adjusted OR=0.90; 95% CI, 0.86 to 0.93), reperfusion therapy (adjusted OR=0.75; 95% CI, 0.70 to 0.80), or timely reperfusion (door-to-needle time ≤30 minutes: adjusted OR=0.78; 95% CI, 0.65 to 0.92; door-to-balloon time ≤90 minutes: adjusted OR=0.87; 95% CI, 0.79 to 0.95). Women also experienced lower use of cardiac catheterization and revascularization procedures after AMI.

Conclusions—

Overall, no sex differences in in-hospital mortality rates after AMI were observed after multivariable adjustment. However, women with STEMI had higher adjusted mortality rates than men. The underuse of evidence-based treatments and delayed reperfusion among women represent potential opportunities for reducing sex disparities in care and outcome after AMI.
Distinct Roles of Protease-Activated Receptors in Signal Transduction Regulation of Endothelial Nitric Oxide Synthase
Authors: Suzuki Hiroyuki , Motley Evangeline D. , Eguchi Kunie , Hinoki Akinari , Shirai Heigoro , Watts Vabren , Stemmle Laura N. , Fields Timothy A. , Eguchi Satoru
Published: December 2008

Protease-activated receptors (PARs), such as PAR1 and PAR2, have been implicated in the regulation of endothelial NO production. We hypothesized that PAR1 and PAR2 distinctly regulate the activity of endothelial NO synthase through the selective phosphorylation of a positive regulatory site, Ser1179, and a negative regulatory site, Thr497, in bovine aortic endothelial cells. A selective PAR1 ligand, TFLLR, stimulated the phosphorylation of endothelial NO synthase at Thr497. It had a minimal effect on Ser1179phosphorylation. In contrast, a selective PAR2 ligand, SLIGRL, stimulated the phosphorylation of Ser1179with no noticeable effect on Thr497. Thrombin has been shown to transactivate PAR2 through PAR1. Thus, thrombin, as well as a peptide mimicking the PAR1 tethered ligand, TRAP, stimulated phosphorylation of both sites. Also, thrombin and SLIGRL, but not TFLLR, stimulated cGMP production. A Gqinhibitor blocked thrombin- and SLIGRL-induced Ser1179phosphorylation, whereas it enhanced thrombin-induced Thr497phosphorylation. In contrast, a G12/13inhibitor blocked thrombin- and TFLLR-induced Thr497phosphorylation, whereas it enhanced the Ser1179phosphorylation. Although a Rho-kinase inhibitor, Y27632, blocked the Thr497phosphorylation, other inhibitors that targeted Rho-kinase failed to block TFLLR-induced Thr497phosphorylation. These data suggest that PAR1 and PAR2 distinctly regulate endothelial NO synthase phosphorylation and activity through G12/13and Gq, respectively, delineating the novel signaling pathways by which the proteases act on protease-activated receptors to potentially modulate endothelial functions.
Mechanisms Underlying Improved Recovery of Neurological Function After Stroke in the Rodent After Treatment With Neurorestorative Cell-Based Therapies
Authors: Chopp Michael , Li Yi , Zhang Zheng Gang
Published: December 2008

We discuss the mechanisms of action underlying the beneficial effects of treating ischemic stroke in the rodent with exogenously administered cells. The essential hypothesis proposed is that the administered cells enhance recovery of neurological function by stimulating the production of restorative factors by parenchymal cells. These activated endogenous brain cells evoke white matter remodeling in the brain and the spinal cord and generate microenvironments within the injured brain that amplify brain plasticity and lead to improvement in neurological function poststroke.
Remodeling the Brain With Behavioral Experience After Stroke
Authors: Jones Theresa A. , Allred Rachel P. , Adkins DeAnna L. , Hsu J. Edward , O'Bryant Amber , Maldonado Mónica A.
Published: December 2008

Background and Purpose—

Behavioral experience can drive brain plasticity, but we lack sufficient knowledge to optimize its therapeutic use after stroke.

Methods—

We outline recent findings from rodent models of cortical stroke of how experiences interact with postinjury events to influence synaptic connectivity and functional outcome. We focus on upper extremity function.

Results—

After unilateral cortical infarcts, behavioral experiences shape neuronal structure and activity in both hemispheres. Experiences that matter include interventions such as skill training and constraint-like therapy as well as unguided behaviors such as learned nonuse and behavioral compensation. Lateralized behaviors have bihemispheric influences. Ischemic injury can alter the sensitivity of remaining neocortical neurons to behavioral change and this can have positive and negative functional effects.

Conclusions—

Because experience is ongoing in stroke survivors, a better understanding of its interaction with brain reorganization is needed so that it can be manipulated to improve function and prevent its worsening.
Childhood-Limited Versus Persistent Antisocial Behavior
Authors: Veenstra René , Lindenberg Siegwart , Verhulst Frank C. , Ormel Johan
Published: December 2008

Possible differences between childhood-limited antisocial youth and their stable high-antisocial counterparts were examined. Children were 11 years old at wave 1 (T1) and 13.5 at wave 2 (T2). At both waves, the same parent, teacher, and self-reports of antisocial behavior were used. Stable highs and childhood-limited antisocial youth differed somewhat in family and individual background. Stable highs had less effortful control, perceived more overprotection, had a higher level of familial vulnerability to externalizing disorder, and lived less often with the same parents throughout their lives than the childhood-limited group. Both groups had similar levels of service use before T1, but after that period, the childhood-limited youth received more help from special education needs services than from problem behavior services, and vice versa for stable highs. The results suggest that the childhood-limited antisocial youth recovered not only from antisocial behavior but also from academic failure, peer rejection, and internalizing problems.
TV news and the echo of Murrow
Authors: Barnett Steven
Published: December 2008

Television journalism in the UK honours the vision of America’s greatest newsman. But for how long can standards be maintained?

Fifty years after Edward R Murrow, the man credited with inventing television journalism in America, made a famous speech to the annual convention of the Radio and Television National Directors Association, media professor Barnett examines the state of TV in the UK and the U.S. and writes: “American television journalism has failed; British television journalism – for the time being – has succeeded. Why? And for how long?”
`I do not Attach Great Significance to it': Taking Note of `The Holocaust' in English Case Law
Authors: Herman Didi
Published: December 2008

The first part of this article traces the history of the word `holocaust' and the phrase `the Holocaust' in English judicial discourse, both in cases where the mass killing of Jewish Europeans in the early 1940s was a relevant issue, and the many more cases where it was not. The second part of the article returns to a selection of the recent cases, arguing that when the Holocaust is referred to in contemporary judgments it tends to be spliced in as a form of stock footage, and suggest that this routinized manoeuvre succeeds in misremembering the past, rather than contributing to any substantive comprehension of the events the phrase is intended to describe. More than this, however, the uses of the Holocaust by the judges may also reinforce particularly English understandings of Jews and Jewishness. Far from acting as a mnemonic device to recall atrocity, the Holocaust can in fact act as an aid to remembering what it is `the English' find distasteful and alien about `the Jew'.
Sacred Mountains and Profane Dollars: Discourses about Snowmaking on the San Francisco Peaks
Authors: Sefiha Ophir , Lauderdale Pat
Published: December 2008

This research examines media, interview and legal-historical documentation surrounding the current proposal to manufacture snow using reclaimed water at the Snowbowl ski area located on the San Francisco Peaks mountains near Flagstaff, Arizona. The proposal has drawn sharp protest from both American Indian Nations who call the area sacred, and environmentalists who question the safety of the reclaimed water. We examine the process by which local coalitions attempt to define environmental, spiritual, and economic values that will resonate with others. These highly mediated activities create contested territory whereby groups attempt to package and frame specific definitions of these values. This debate exposes hegemonic assumptions that aid us in deconstructing conflicting understandings of colonialism, racism, and other issues that typically go unacknowledged. Weber's discussion of rationality and commensurability is employed for understanding why sacred justice claims continue to be largely ignored. This research indicates that not only is this a case of epistemological incompatibility, but an active attempt to discredit and disenfranchise a specific group. Two interwoven themes emerged from our analysis: `Indians as Greedy' and `Indians as Hypocrites'. These themes are also found in the legal history of sacred site protection in the United States. We argue the fundamental lack of acknowledgement of Indian cosmology persists via a dichotomous conception of religion and civic society, which also suggests a separation of dominant forms of civic decision-making.
When Businesses Go to School
Authors: Manteaw Bob Offei
Published: December 2008

This paper foregrounds education for sustainable development (ESD) and corporate social responsibility (CSR) as emergent discourses that need conscious efforts to align their ideals. While it explores the capacity of ESD to make significant contribution towards educational thinking and practice, it does so recognising that current neoliberalists’ and capitalists’ agenda, particularly as they relate to formal schooling, contradicts the ideals of education for sustainable development. Using the United States—a capitalist giant—as a focus, the paper employs critical discourse analysis to expose such conceptual and operational contradictions inherent in current business involvement in schools. In calling for a change, the paper draws attention to the need for a conscious alignment of CSR activities both in schools and in the wider community to current ESD agenda. The paper concludes that if CSR is a business’ contribution towards sustainable development, then its pedagogical imperatives must be critically explored.
Creating a Sustainable City through a System of Citizen-based Learning
Authors: Chikami Satoshi , Sobue Kirstie
Published: December 2008

In Japan, environmental education partnerships among citizens, businesses and local government increased since new legislation was introduced in 2003, but there was little evidence of cross-sector collaboration until recently. Nagoya Open University of the Environment is a highly innovative, multi-sectoral citizen learning system founded in 2005 with the objective of positioning Nagoya City as a global centre of excellence in sustainability. This article discusses the university's background and structure and its achievements and outstanding issues, including (1) progress in cross-sector partnerships, (2) the voluntary participation of more than 20,000 citizens, (3) the implementation of classroom-based learning, surveys, field studies and social experiments, (4) the need for expansion and a stronger financial base, and (5) the importance of promoting ESD under the umbrella of Regional Centres of Expertise (RCE), Chubu.
Sexuality, sexual and reproductive health: an exploration of the knowledge, attitudes and beliefs of the Greek-Cypriot adolescents
Authors: Kouta Christiana , Tolma Eleni L.
Published: December 2008

This study examines the knowledge, attitudes and beliefs of Greek-Cypriot adolescents regarding sexuality, sexual and reproductive health in Cyprus. This is the first study in Cyprus that focuses on these issues. During the study, a survey was administered to a random sample of third grade students ( N = 697, Mean age = 14 ± 1 years, 48% males). Descriptive and comparative statistics were primarily used for the data analysis. The results indicated that young Greek-Cypriots have limited knowledge on sexual health issues and that there are gender differences regarding role expectations of sexuality. Thus, in the promotion of healthy sexuality and sexual behaviours among youth, practitioners should include gender and cultural perspectives. Qualitative research is needed to explore in depth how young Greek-Cypriots feel about sexuality and sexual and reproductive health. (Promot Educ, 2008; 15 (4): pp. 24-31)
Health promotion and education policy and practice in urban schools in Liaoning province, China
Authors: Thomas Malcolm , Weng Wenyan
Published: December 2008

This paper reviews the status of health education in urban schools in three cities in Liaoning province, China. The cities represent the upper, middle and lower levels of city economy based on the GDP per person within the province. A self-administered questionnaire was provided to 500 primary and secondary schools and 436 questionnaires (87.2%) were returned completed. The questionnaire assessed health education offerings in the schools, permitting the comparison of similarities and differences in school practices, and the identification of obstacles that prevent schools becoming health promoting. The analysis revealed that 0.7% of schools fulfilled criteria for good status of health education. The negative attitudes of school management, teachers and pupils towards health education, as well as the lack of in-service training for staff, were perceived as key obstacles to school health education. Few provincial and school-based policies mentioned pupil involvement in health policy development and only a small number of schools acknowledged the need to improve community and parental involvement. In this paper we discuss the challenges facing provincial education and health authorities, and make recommendations about how to assist Chinese schools to develop and implement high quality health education initiatives. (Promot Educ, 2008; 15(4): pp. 44-49)
From “Blighted” to “Historic”
Authors: Saito Leland T.
Published: December 2008

Using the example of three buildings in San Diego, the author examines the negotiations between city officials and local residents over competing images of race and history. He shows how the outcomes of these negotiations are used to support and legitimate economic development and historic preservation policies. His main point is that although policies are depicted as race neutral, the results are often racialized. This happens because of the tendency of routine, institutional processes to recognize the history of White communities rather than those of racial minorities, contributing to whiteness. As part of the process of racial formation, activists counter labels of minority neighborhoods as “blighted” and “slums” with the view that they are attractive centers of business, culture, and tourism.
Socio-emotional challenges in international education
Authors: Ujitani Eiko , Volet Simone
Published: December 2008

This article, arising from a study located in a Japanese education setting, analyses the socio-emotional challenges experienced by host (Japanese) and international (Australian) students as they interact in the same international education environment over a period of time. Students' multiple interpretations of critical incidents created by the researchers on the basis of recurrent challenges highlight that intercultural relational development is an interactive, dynamic process that requires sensitivity and reciprocal understanding. The Japanese location of the study contributes to redressing the dominance of studies conducted in English-speaking host environments.
BH3-only protein Bim more critical than Puma in tyrosine kinase inhibitor–induced apoptosis of human leukemic cells and transduced hematopoietic progenitors carrying oncogenic FLT3
Authors: Nordigården Amanda , Kraft Maria , Eliasson Pernilla , Labi Verena , Lam Eric W.-F. , Villunger Andreas , Jönsson Jan-Ingvar
Published: December 2008

Constitutively activating internal tandem duplications (ITD) of FLT3 (FMS-like tyrosine kinase 3) are the most common mutations in acute myeloid leukemia (AML) and correlate with poor prognosis. Receptor tyrosine kinase inhibitors targeting FLT3 have developed as attractive treatment options. Because relapses occur after initial responses, identification of FLT3-ITD–mediated signaling events are important to facilitate novel therapeutic interventions. Here, we have determined the growth-inhibitory and proapototic mechanisms of 2 small molecule inhibitors of FLT3, AG1295 or PKC412, in hematopoietic progenitor cells, human leukemic cell lines, and primary AML cells expressing FLT3-ITD. Inactivation of the PI3-kinase pathway, but not of Ras–mitogen-activated protein (MAP) kinase signaling, was essential to elicit cytotoxic responses. Both compounds induced up-regulation of proapoptotic BH3-only proteins Bim and Puma, and subsequent cell death. However, only silencing of Bim, or its direct transcriptional activator FOXO3a, abrogated apoptosis efficiently. Similar findings were made in bone marrow cells from gene-targeted mice lacking Bim and/or Puma infected with FLT3-ITD and treated with inhibitor, where loss of Puma only provided transient protection from apoptosis, but loss of Bim preserved clonal survival upon FLT3-ITD inhibition.