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Atomically precise metal nanoclusters (NCs) emerge as fascinating synthons in self‐assembled materials. The self‐assembly of metal NCs are highly sensitive to the environment because they have an inorganic‐organic hybridized structure and a relatively complicated conformation. Here, it is shown that when confined in crowded colloids, a water‐soluble Ag9‐cored nanocluster (Ag9‐NC) can self‐ assemble into ultra‐long (up to millimeters) and photoluminescent ribbons with high flexibility. The ribbon contains rectangularly organized columns of Ag9‐NCs and can undergo secondary self‐assembly to form bundled and branched structures. Formation of ribbons is observed in all the tested colloids, including lyotropic liquid crystals and disordered, three‐dimensional network. The high viscosity/elasticity of the crowded colloids weakens gravity‐induced sedimentation of the ribbons, leading to the formation of an interesting class of inorganic‐organic composite materials where the hard Ag‐containing skeleton strengthens the soft matter. The simultaneously occurring symmetry breaking during the self‐assembly of Ag9‐NCs gives uncontrolled supramolecular chirality, which can be tuned through the majority rule and soldier‐and‐sergeant rule by the introduction of chiral seeds. The regulated chirality and the intrinsic photoluminescence of the Ag9‐NCs ribbons impart the composite material circularly polarized luminescence, opening the door for a variety of potential applications. [ABSTRACT FROM AUTHOR]

This paper challenges the commonly held view that the Classical Greek potential optative has a subjective epistemic semantics, the result of a conceptual confusion of subjectivity and epistemic modality inherited from our standard grammars. I propose that this view becomes less convincing when the optative's unique interaction with the subjective particles ἦ and ἄρα is incorporated into the analysis. Rather, the potential optative has a non-subjective epistemic semantics presenting an epistemic judgment as interpersonally accessible to the conversational participants. Frequencies of combination with ἦ and ἄρα, linguistic tests for subjectivity on the potential optative, and contrastive contextual analyses corroborate this view. [ABSTRACT FROM AUTHOR]

Given the long history of effect size (ES) indices (Olejnik and Algina Contemporary Educational Psychology, 25, 241-286 ) and various attempts by APA and AERA to encourage the reporting and interpretation of ES to supplement findings from inferential statistical analyses, it is essential to document the impact of APA and AERA standards on ES reporting practices. In this paper, we investigated the impact by examining findings from 31 published reviews and our own review of 451 articles published in 2009 and 2010. The 32 reviews were divided into two periods: before and after 1999. A total of 116 journals were reviewed. Findings from these 32 reviews revealed that since 1999, the ES reporting has improved in terms of its rate, variety, interpretation, confidence intervals, and fullness. Yet several inadequate practices still persisted: (1) the dominance of Cohen's d, and the unadjusted R/η, (2) the mere labeling of ES, (3) the under-reporting of confidence intervals, and (4) a lack of integration between ES and statistical tests. The paper concludes with resources on Internet and recommendations for improving ES reporting practices. [ABSTRACT FROM AUTHOR]

Abstract: In the first production run of the WASA experiment at COSY, the eta decay into three neutral pions was measured in proton–proton interactions at a proton beam kinetic energy of 1.4 GeV. The Dalitz plot of the three pions was studied using fully reconstructed events, and the quadratic slope parameter α was determined to be . The result is consistent with previous measurements and further corroborates the importance of pion–pion final state interactions. [Copyright &y& Elsevier]

The contact mass in the Rochow reaction was analyzed to understand catalyst deactivation during the reaction. Changes in crystalline structure, particle surface morphology, and the elemental composition of the contact mass were measured by XRD, SEM, EDX, and XRF, respectively, at four different reaction conversions. The results indicate that the main reason for contact-mass deactivation is copper enrichment on the surface of silicon. Coke deposition may hamper Cu diffusion and result in the copper enrichment. [ABSTRACT FROM AUTHOR]

The precipitate size, distribution and volume fraction in an AlZnMgCu-1.0 wt.% Li alloys during various aging conditions were investigated by small-angle X-ray scattering and transmission electron microscopy. According to the selected area diffraction patterns, the prime precipitates in this alloy are η′ phases, not δ′ phases. During the temperature ranging from 120 to 160 °C, the growing of precipitates in the 7055-1.0 wt.% alloys is not apparent. From 120 to 150 °C, the varieties of precipitate volume fraction depend on the competition between dissolution rate of GP zones and nucleation rate of η′. At 160 °C, the growing of η′ precipitates is undergoing a Lifshitz–Slyozov–Wagner coarsening process, and the prime thermodynamic reaction is the nucleation growth of η′ precipitates. [Copyright &y& Elsevier]

It is difficult for most inorganic chemists to be aware of the availability of the many new techniques, described largely in analytical chemistry, environmental chemistry, and biomedical journals, which are increasingly of value in the separation and characterization of complexes of transition metals. Additionally, the design and use of supported transition metal complexes as sites for molecular recognition in the separation of biomolecules and organic materials has the potential to dominate multi-billion dollar industries in proteins and chiral drugs. This review serves as a roadmap for inorganic chemists to the recent chromatographic literature. The review covers advances in separation methods that involve transition metal chemistry which have occurred in the decade of 1992 through early 2003 with 360 references. The review is intended to assist readers in finding key papers that illustrate techniques of chromatography that might be applicable to purposes in the reader’s laboratory. Covered topics include the standard separation of inorganic ions and metal complexes, capillary electrophoresis methods (CE, CZE, MEKC), electrochemical detection in flow methods by [Ru(bpy)3]3+/2+ cycling in response to analytes, separations of metal complexes of interest to environmental and biomedical disciplines via size exclusion chromatography (SEC), and detection methods with electrospray mass spectrometry (ESI-MS). Advances in affinity chromatography in the separation of peptide, proteins and biopolymers (IMAC) and of organic substrates (IMCOS) are discussed. Recent advances in understanding the mechanisms of chromatographic separations, and of the technique of polymer imprinting to produce selective recognition sites for metal ions and metal complexes are described. [Copyright &y& Elsevier]

The cationic manganese tricarbonyl complexes containing η6-2-methylhydroquinone (2a), η6-2,3-dimethylhydroquinone (3a), η6-2-t-butylhydroquinone (4a), η6-tetramethylhydroquinone (5a) and η6-4,4′-biphenol (6a) are readily deprotonated to the corresponding neutral (η5-semiquinone)Mn(CO)3 (2b–6b) and anionic (η4-quinone)Mn(CO)3− (2c–5c) complexes. The X-ray structures of 2b–6b feature strong intermolecular hydrogen bonding interactions that result in the formation of supramolecular organometallic networks. Significantly, the substitution pattern at the semiquinone ring affects the stereochemistry of the hydrogen bonding interactions. NMR spectra of 2b, 3b and 5b reveal dynamic hydrogen bonding in solution. [Copyright &y& Elsevier]

Hydride ruthenium complexes, RuHCl(CO)(PPh3)2(L–L′) 3 (L–L′=bidentate ligand having nitrogen and oxygen) react with allenes to give Ru(η3-allyl)(CO)(PPh3)(L–L′) complexes 5 in good yields via hydrometalation reaction. The complexes 5 have planar chirality at the η3-allyl ligand and central chirality at the Ru metal, and consist of one pair of enantiomers. Ligand substitution reaction of Ru(η3-allyl)Cl(CO)(PPh3)2 complexes 6 with bidentate ligands (L–L′) also afford the complexes 5 which have the same stereochemistry as those formed by the hydrometalation reaction. The planar chirality is controlled by the central chirality at the Ru metal in both the formations of the complexes 5. The structure of 5a (L–L′=N–N bidentate ligand) was determined by the X-ray crystal structure analysis. [Copyright &y& Elsevier]

By means of arene ligand exchange of the triple deckers [{(η5-R1–5C5)Co}2-μ-(η4:η4-toluene)] (R1–5=Me, R1–3=tert-butyl) at room temperature a number of mono-, di-, and tri-nuclear sandwich complexes of the polycondensed aromatics polycyclic aromatic hydrocarbons (PAHs) tetracene, benzo[a]pyrene, perylene, triphenylene and benzo[a]triphenylene have been synthesized. For triphenylene and benzo[b]triphenylene however, a threefold coordination of [(η5-C5Me5)Co] fragments in the periphery of these PAHs is found, tetracene allows for a twofold coordination of two [(η5-C5Me5)Co] fragments in the ring periphery leaving a central naphthalene unit of this PAH uncomplexed. Perylene serves as a twofold coordination site for [(η5-1,2,4 tri-tert-butyl-C5H2)Co] fragments which are coordinated in each of the two naphthalene fragments of this π-perimeter. [Copyright &y& Elsevier]

The endo- and exo-complexes [Mo{η3-C3H4(CH3)}(η2-S2CNC4H8)(CO)(η2-diphos)] (diphos: dppm={bis(diphenylphosphino)methane} (2); dppe={1,2-bis(diphenylphosphino)ethane} (3) are prepared by reacting the 16-electron complex [Mo{η3-C3H4(CH3)}(η2-S2CNC4H8)(CO)2] (1) with diphos in refluxing acetonitrile. The orientations of endo and exo are defined in such a way that the open face of the allyl group and carbonyl group are in the same direction in the former and in the opposite direction in the latter. The variable temperature 1H NMR was used to confirm that there was no allyl rotation behavior of endo↔exo interconversion of 2 before the thermal decomposition. X-ray crystal structure of exo-2 has been employed to elucidate the exo orientation and the methyl moiety of the allyl ligand is found to orient away from the dppm ligand. [Copyright &y& Elsevier]

Treatment of complex [Ru(η3:η3-C10H16)Cl2(κ1-P-Ph2PCH2PPh2)] (2) with AgBF4 yields the chelate derivative [Ru(η3:η3-C10H16)Cl(κ2-P,P-Ph2PCH2PPh2)][BF4] (3). Attempts to generate species structurally related to 2 by reaction of the bis(allyl)-ruthenium(IV) dimer [{Ru(η3:η3-C10H16)(μ-Cl)Cl}2] (1) with diphosphines Ph2P(CH2)nPPh2 (n=2, 3, 4) failed, obtaining instead the dinuclear compounds [{Ru(η3:η3-C10H16)Cl2}2{μ-Ph2P(CH2)nPPh2}] (n=2 (4a), 3 (4b), 4 (4c)). In contrast, mononuclear neutral species [Ru(η3:η3-C10H16)Cl2{κ1-P-Ph2P(CH2)nP(&z.dbnd6;O)Ph2}] (n=1 (5a), 2 (5b), 3 (5c), 4 (5d)) have been easily prepared by reaction of 1 with the corresponding diphosphine-monoxide Ph2P(CH2)nP(&z.dbnd6;O)Ph2 (n=1, 2, 3, 4). Treatment of 5a,b with AgBF4 allows the formation of cationic derivatives [Ru(η3:η3-C10H16)Cl{κ2-P,O-Ph2P(CH2)nP(&z.dbnd6;O)Ph2}][BF4] (n=1 (6a), 2 (6b)). [Copyright &y& Elsevier]

Spectroscopic and structural data of 15 complexes with the general formula of RO(O)CCH2Co(CO)3PPh3 indicate a novel coordination mode of the α-ester group to the central cobalt atom, which was found to be crucial in the formation of configurational chirality of the ester carbon atom. Stereoselective self-assembly, elongated ester carbonyl bond lengths, reduced carbonyl stretching frequencies, and 13C/31P NMR coupling constants show an activated α-ester group compared to the uncoordinated ester or to that in a more distal position. Density functional calculations were carried out to describe the nature of this new bonding, termed earlier as ‘autosolvation’. [Copyright &y& Elsevier]

A study of reactions of η3-allenyl/propargyl complexes of platinum and palladium with transition-metal hydrides and secondary amines and of η3-trimethylenemethane (η3-TMM) complexes of platinum with unsaturated electrophiles is presented. The reaction of [(PPh3)2Pt(η3-CH2CCPh)]OTf (1aOTf) with Cp(CO)2RuH affords the η3-allyl complex [(PPh3)2Pt(η3-CH2CHC(Ph)Ru(CO)2Cp)]OTf, whereas that of 1aOTf with Cp2Zr(Cl)H furnishes [(PPh3)2Pt(η3-CH2CHCHPh)]OTf (3OTf). The source of the CHPh hydrogen in the latter reaction appears to be adventitious H2O, as evidenced by the formation of [(PPh3)2Pt(η3-CH2CHCDPh)]OTf when 1aOTf was treated with D2O and Cp2Zr(Cl)H. Possible mechanisms of formation of 3OTf are presented. The secondary amines R2NH (R=i-Pr or sec-Bu) react with 1aOTs and its palladium analog, 1bOTs, to give the η3-(2-aminoallyl) complexes [(PPh3)2M(η3-CH2C(NR2)CHPh)]OTs (M=Pt, Pd). Competition studies reveal the following order of reactivity, attributed to steric effects: Et2NH (74 and 38)>(i-Pr)2NH (3.5 and 5)>(sec-Bu)2NH (1) for 1aOTs and 1bOTs, respectively. The complex 1aOTs reacts much faster with Et2NH than with EtOH. Reactions of the η3-TMM complexes (PPh3)2Pt(η3-CH2C(C(CO2Me)2)CHR) (R=Me (7), Ph (8)) with the very strong electrophiles/polarophiles TCNE and p-toluenesulfonyl isocyanate (TSI) lead to [3+2] cycloaddition of the electrophile to the η3-TMM ligand, and the resulting cycloadduct is isolated either free (with TSI) or complexed as an alkene to the metal (with TCNE). The weaker electrophiles diethyl fumarate and fumaronitrile (E) react with 7 or 8 to furnish (PPh3)2PtE and a [3+3] coupling product of the η3-TMM ligand. All new compounds were characterized by a combination of elemental analysis, mass spectrometry and 1H, 13C{1H} and 31P{1H} NMR spectroscopy. [Copyright &y& Elsevier]

Ketenylidenetriphenylphosphorane, Ph3P&z.dbnd6;C&z.dbnd6;C&z.dbnd6;O (1), presents, at a first glance, the characteristics of both ylides and ketenes, but its behavior is that typical of ylides, undergoing electrophilic attacks on the ylidic carbon that transform 1 into a ‘true’ ketene having PPh3 as one substituent. Here we review the synthesis, the chemical–physical properties as well as the reactivity of these compounds, with a particular emphasis on the interaction with transition metal complexes. With this compound it has always been observed that the ylidic carbon of 1 binds to coordinatively unsaturated metals, which act as electrophiles, forming η1-ketenyl derivatives that can also be viewed as stabilized metal-substituted ketenes. Perspectives for the synthesis of other metal-substituted ketenes and developments on their study are also presented. [Copyright &y& Elsevier]

Mo(PMe3)6 reacts with [pzBut2]H at 80 °C to give [η2-pzBut2]Mo(PMe3)4H, the first structurally characterized d4 η2-pyrazolyl complex of molybdenum. The hydride ligand of [η2-pzBut2]Mo(PMe3)4H is displaced from the mean Mo&z.sbnd;N&z.sbnd;N&z.sbnd;Pcis&z.sbnd;Pcis plane, such that the distorted seven-coordinate geometry may be viewed as being based on a distorted dodecahedron with a vacant coordination site. DFT (B3LYP) calculations suggest that the origin of the displacement of the hydride ligand is due to steric interactions with the pair of ‘cis’ PMe3 ligands. [Copyright &y& Elsevier]

The Michael addition of chiral organolithiums, resulting from benzylic metallation of certain η6-chromiumtricarbonyl complexes, to α,β-unsaturated ketones and esters, is strongly influenced by the presence of chlorotrimethylsilane. In most cases yields of Michael adducts are greatly improved in the presence of Me3SiCl. Some further transformations of the Michael adducts were carried out, including a ring expansion process of a cyclohexanone derivative and a SmI2 mediated cyclisation of a complex bearing an acyclic ketone appendage. [Copyright &y& Elsevier]

Temperature-induced unfolding of the leucine zipper, an α-helical, double-stranded, coiled-coil, was studied by circular dichroism spectroscopy, spectrofluorimetry and heat capacity scanning calorimetry. It is shown that this process does not represent a simple two-state transition, as previously believed, but consists of several stages. The first transition starts at the very beginning of heating from 0 °C and proceeds with significant heat absorption and decrease of ellipticity. This transition does not depend on the concentration of protein and is sensitive to modification of the N terminus; it is therefore associated with unfolding or fraying of this part of the leucine zipper. The second transition takes place at a considerably higher temperature; it is more pronounced than the first one and does not depend on the concentration of protein, i.e. it is unimolecular. This transition is sensitive to modification of both termini of the leucine zipper and affects the optical properties of a tryptophan residue placed in the central part of the zipper. It therefore involves the whole dimer but does not result in its dissociation, presumably being associated with some repacking of the coiled-coil. This second transition is followed at higher temperatures by the concentration-dependent cooperative unfolding/dissociation of the two strands. The enthalpy and entropy of the temperature-induced structural changes of the leucine zipper that take place before its cooperative unfolding/dissociation comprises almost 40% of the total enthalpy and entropy of unfolding of the completely folded coiled-coil, the state in which it appears to be below 0 °C. Comparison of the total enthalpy of leucine zipper unfolding with that of a single-stranded α-helix shows that their temperature-dependence correlates with the extent of intramolecular non-polar contacts and allows an assessment of the enthalpy of hydrogen bonding in α-helices, which appears to be about 3.3 kJ mol−1 at 20 °C. [Copyright &y& Elsevier]

The backbone dynamics of the J domain from polyomavirus T antigens have been investigated using 15N NMR relaxation and molecular dynamics simulation. Model-free relaxation analysis revealed picosecond to nanosecond motions in the N terminus, the I–II loop, the C-terminal end of helix II through the HPD loop to the beginning of helix III, and the C-terminal end of helix III to the C terminus. The backbone dynamics of the HPD loop and termini are dominated by motions with moderately large amplitudes and correlation times of the order of a nanosecond or longer. Conformational exchange on the microsecond to millisecond timescale was identified in the HPD loop, the N and C termini, and the I–II loop. A 9.7 ns MD trajectory manifested concerted swings of the HPD loop. Transitions between major and minor conformations of the HPD loop featured distinct patterns of change in backbone dihedral angles and hydrogen bonds. Fraying of the C-terminal end of helix II and the N-terminal end of helix III correlated with displacements of the HPD loop. Correlation of crankshaft motions of Gly46 and Gly47 with the collective motions of the HPD loop suggested an important role of the two glycine residues in the mobility of the loop. Fluctuations of the HPD loop correlated with relative reorientation of side-chains of Lys35 and Asp44 that interact with Hsc70. [Copyright &y& Elsevier]

A physiologically based nonlinear active cochlear model is presented. The model includes the three-dimensional viscous fluid effects, an orthotropic cochlear partition with dimensional and material property variation along its length, and a nonlinear active feed-forward mechanism of the organ of Corti. A hybrid asymptotic and numerical method combined with Fourier series expansions is used to provide a fast and efficient iterative procedure for modeling and simulation of the nonlinear responses in the active cochlea. The simulation results for the chinchilla cochlea compare very well with experimental measurements, capturing several nonlinear features observed in basilar membrane responses. These include compression of response with stimulus level, two-tone suppressions, and generation of harmonic distortion and distortion products. [Copyright &y& Elsevier]

The η3-allenyl/propargyl complex [(PPh3)2Pt(η3-CH2CCPh)]OTf (1OTf) undergoes addition reactions with a number of oxygen nucleophiles in CH2Cl2 solution at ambient temperature. With H2O, it yields the binuclear oxygen-bridged η3-allyl [{(PPh3)2Pt(η3-CH2CCHPh)}2O](OTf)2 (2(OTf)2). With primary and secondary alcohols, it rapidly affords the η3-(2-alkoxyallyl) complexes [(PPh3)2Pt(η3-CH2C(OR)CHPh)]OTf (R=Et (3OTf), i-Pr (4OTf), CH2CMe3 (5OTf), CH2CH&z.dbnd6;CH2 (7OTf)), whereas with tertiary alcohols, in slower reactions, it gives both 2(OTf)2 and [(PPh3)2Pt(η3-CH2C(OR)CHPh)]OTf (R=CMe3, C(Me)2Et (6OTf)). There is no reaction at ambient temperature between 1OTf and phenols; however, 1OTf and PhOH afford [(PPh3)2Pt(η3-CH2C(OPh)CHPh)]OTf (8OTf) in the presence of NEt3. Competition studies reveal the following reactivity order, attributed to steric effects: Me3CCH2OH(1.0)

A new iron Lewis acid catalyst, [(η5:η1-C5H4CH(Ph)OPPh2)Fe(CO)(THF)]+[BF4]− featuring a cyclopentadienyl ring that is tethered to a terminal diphenylphosphinite moiety was created. This is the first complex to contain a chelating η5:η1-cyclopentadienyl-phosphinite ligand. This new racemic iron Lewis acid was tested and found to be an effective catalyst in an aziridine-forming reaction. An asymmetric alcohol that is a precursor of the chiral catalyst was synthesized with greater than 95% ee. Upon ligation of the diphenylphosphinite to the iron center, a 3:2 mixture of diastereomers was formed. The diastereomeric mixture of the asymmetric catalysts was utilized in the aziridine-forming reaction and produced the cis-aziridine with low enantiomeric excess. [Copyright &y& Elsevier]

Protonation of η2-enyne rhenium complex C5Me5(CO)2Re(η2-3,4-trans-PhC&z.tbnd6;CCH&z.dbnd6;CHPh) (24) occurred at the coordinated alkyne to produce 1-metallacyclopropene complex C5Me5(CO)2Re[η2-trans-(PhHC&z.dbnd6;CH)CCHPh]+BF4 − (26), instead of protonation at the non-coordinated alkene to produce an η3-propargyl complex. Protonation of the alkene coordinated η2-enyne rhenium complex C5Me5(CO)2Re(η2-1,2-cis-PhHC&z.dbnd6;CHC&z.tbnd6;CPh] (25) occurred at the non-coordinated alkyne to produce exo-alkylidene η3-allyl complex C5Me5(CO)2Re(η3-exo,anti-CHPhCHC&z.dbnd6;CHPh)+BF4 − (27), instead of protonation at the coordinated alkene to produce an η3-propargyl complex. Protonation of η2-diyne complex C5Me5(CO)2Re(η2-CH3C&z.tbnd6;CC&z.tbnd6;CCH3) (32) at −78 °C produced the rhenium hydride complex trans-C5Me5(CO)2ReH(η2-CH3C&z.tbnd6;CC&z.tbnd6;CCH3)+BF4 − (33), which was converted to exo-alkylidene η3-propargyl complexes C5Me5(CO)2Re[η3-(CH3CH&z.dbnd6;)CC&z.tbnd6;CCH3]+BF4 − (34a and 34b) at 0 °C. [Copyright &y& Elsevier]

Regioselective addition of hydrogen sulfate or dihydrogen phosphate anion to cationic η3-allenyl–propargyl platinum complex [Pt(PPh3)2(η3-C3H3)](BF4) (1) generates a new neutral η3-2-sulfatoallyl complex Pt(PPh3)2[η3-CH2C(OSO3)CH2] (2) or a η3-2-hydrogenphosphato-allyl complex Pt(PPh3)2[η3-CH2C(OPO3H)CH2] (5), respectively. Further addition of 5 to 1 gives a cationic η6-diallylphosphato dinuclear complex {Pt(PPh3)2[η3-(CH2)2C]2(PO4)}(BF4) (6) which undergoes hydrolysis to yield a μ4-phosphate-bridging diplatina complex Pt2(PPh3)4[μ4-(PO4)] (7) along with the formation of acetone. The structures of complexes 2 and 7 have been determined by crystallography. [Copyright &y& Elsevier]

Dinuclear η6-areneruthenium(II) complex of the formula [Ru2{η6:η1:μ-C6H5(CH2)3O}2(μ-Cl)]+ (2) was prepared by treatment of Ru{η6-C6H5(CH2)3OH}Cl2 with base. X-Ray structure analysis revealed 2 to contain two Ru centers bridged by Cl ligand as well as by two alkoxo groups, which are tethered to η6-arene ligands. Treatment of 2 with Ag+ in acetonitrile afforded dicationic complex [Ru2{η6:η1:μ-C6H5(CH2)3O}2(CH3CN)2]2+ (3) in which two CH3CN ligands are located trans to each other with respect to the Ru2O2 plane. Irradiation with UV light (300–400 nm) of a CH3CN solution of 3 and trans-azobenzene gave cis-azobenzene complex [Ru2{η6:η1:μ-C6H5(CH2)3O}2(μ-cis-PhN&z.dbnd6;NPh)]2+ (4). Cis-azobenzene ligand of 4 dissociated under irradiation of light (>510 nm) to give 3 in CH3CN or disulfide complex [Ru2{η6:η1:μ-C6H5(CH2)3O}2(μ-PhSSPh)]2+ (6) in the presence of the disulfide. X-ray structure determination of 4 and 6 established bridge coordination of cis-azobenzene and disulfide ligands. Reaction of 3 with pyridazine afforded similar dimeric complex [Ru2{η6:η1:μ-C6H5(CH2)3O}2(μ-pyridazine)]2+ (7), while the reaction with bipyridine afforded monomeric alkoxo chelate complex [Ru{η6:η1-C6H5(CH2)3O}(bipy)]+ (8). [Copyright &y& Elsevier]

To obtain the dynamic range of an auditory afferent, the neuron’s firing rate is plotted versus stimulus level, and the dynamic range is taken as the difference between the threshold for evoked firing, and the level at which firing rate saturates. Those dynamic range endpoints are typically defined in terms of the neuron’s spontaneous firing rate and its maximum firing rate, according to a plurality of schemes, each of which depends on user-chosen sets of numerical criteria. The dynamic ranges predicted by some of these schemes are compared for the first time, and the resulting estimates can differ by a factor of 2. A step can be taken towards standardizing the measurement of neuronal dynamic range, if dynamic range is incorporated into a rate-level function as a parameter. To build this function, it is first assumed that the neuron’s rate-level response reaches half its maximum at a level half-way between the threshold and the level at saturation, i.e. at threshold plus half the dynamic range. Then the firing rates at threshold and at threshold plus dynamic range are defined according to the most popular of the endpoint schemes. The resulting equation produces credible estimates of neuronal properties when fitted, and correctly predicts the behavior of the slope of the empirical rate-level plot [McGee, 1983. M.S. thesis, Creighton University; Ohlemiller et al., 1991. J. Acoust. Soc. Am. 90, 274–287]. Thus, despite not being deterministic, the new equation has remarkable predictive power. When two of the rate-level functions are added and weighted, the resulting equation fits sloping-saturating data better than any functions presently employed. [Copyright &y& Elsevier]

Extracellular polysaccharides (EPSs) produced by an Erwinia sp associated with a fungal canker disease of Eucalyptus were fractionated into one polysaccharide that was identified with that produced by Erwinia chrysanthemi strains SR260, Ech1, and Ech9, and the other distinctively different from any other EPS produced by E. chrysanthemi strains so far studied. Their structures were determined using a combination of chemical and physical techniques including methylation analysis, low pressure gel-filtration, and anion-exchange chromatographies, high-pH anion-exchange chromatography, mass spectrometry and 1D and 2D 1H NMR spectroscopy. The new polysaccharide, identified as EPS Teranera, has the following structure:The molecular weights of the polysaccharides range from 3.2–6.2×105 and their hydrodynamic properties are those of polydisperse, polyanionic biopolymers with pseudoplastic, non-thixotropic flow characteristics in aqueous solutions. [Copyright &y& Elsevier]

The theory and experiments on model and biomembrane flexoelectricity are reviewed. Biological implications of flexoelectricity are underlined. Molecular machinery and molecular electronics applications are pointed out. [Copyright &y& Elsevier]

Ketenylidenetriphenylphosphorane, Ph3PC&z.dbnd6;C&z.dbnd6;O, 1, has been used to synthesize platinum-substituted ketenes [PtMe{η1-C(PPh3)CO}L2]BF4, 2a, b (L2=1,5-cyclooctadiene, cod (a), 1,2-bis(diphenylphosphino)ethane, diphos (b)). Parent compound [PtCl{η1-C(PPh3)CO}L2]BF4, 3, with L2=cis-1,2-bis(diphenylphosphino)ethene, diphoe, was also synthesized, which is stable only at low temperature. The stability of 2 and 3 and the reactivity of the C&z.dbnd6;C&z.dbnd6;O moiety have been examined and discussed in terms of the electronic and steric characteristics of the ancillary ligands, also taking into account the reactivity of the ‘PtXL2’ fragment with other carbonyl stabilized phosphorus ylides, Ph3PCHCOR (R=Me, Ph, OMe, OEt). [Copyright &y& Elsevier]

The type of ligand on an allenylpalladium complex, which was prepared from propargyl alcohol derivative and Pd(0), plays an important role in determination of the ring size of the cyclized compound. An intermediary palladium complex bearing a monodentate ligand gave a cyclized compound via palladacycle, while that bearing a bidentate ligand gave one-carbon elongated cyclized compound via a η3-propargylpalladium complex. [Copyright &y& Elsevier]

The synthesis of new derivatives based on a Ru(Ph2P&z.sbnd;arene)(POHPh2) fragment, possessing nitrile, isonitrile and phosphine ligands, are reported. The new nitrile compounds, e.g. [Ru(H2O)(RCN)2(Ph2P&z.sbnd;η1arene)(POHPh2)](OTf)2, R=Me, p-tolyl, reveal a new and unexpected weak η1 π-bonding mode from a single CH&z.sbnd;biaryl arene carbon to the ruthenium atom, as demonstrated by 13C-NMR. The solid-state structures for two examples are reported. In one complex a new Ru&z.sbnd;P&z.sbnd;O&z.sbnd;C&z.dbnd6;N&z.sbnd;H five-membered ring is formed due to the P&z.sbnd;OH oxygen attack on the complexed p-tolyl nitrile. [Copyright &y& Elsevier]

We report on the exclusive production of ω and η mesons in p + p reactions at 3.5 GeV beam kinetic energy. Production cross sections, angular distributions and Dalitz plots of both mesons were determined. Moreover, the relative contribution of the N(1535) resonance in η production at this energy was evaluated. We conclude that η mesons produced via N(1535) exihibit an isotropic angular distribution, whereas those produced directly show a strong anisotropic distribition. ω mesons show a slightly anisotropic angular distribition. [ABSTRACT FROM AUTHOR]