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Synthesis of linear trinuclear complexes containing the [tris(dimethylglyoximato)-metalate(II)]4- anion as bridging ligand of general formula [LCrIII{μ-(dmg)3M}CrIIIL]1+/2+/3+/4+ as perchlorate salts, where M = (H+)2 (1 and 2), absent (3), (H+)4 (4), Li(I) (5), Mg(II) (6), Cu(II) (7), Ni(II) (8), Ni(IV) (9), Co(III) (10), Fe(II) (11), Fe(III) (12) and Mn(II) (13), has been achieved by stepwise reactions of the LCr unit with in situ prepared M(dmg)3 n - ions, where L represents 1,4,7-trimethyl-1,4,7-triazacyclononane and dmg2- is the dimethylglyoximato dianion. The clathrochelate complexes 1−13 have been characterized on the basis of elemental analysis, mass spectrometry, IR, UV−vis, Mössbauer, and EPR spectroscopies, and variable-temperature (2−295 K) magnetic susceptibility measurements. They are quasi-isostructural with the terminal chromium(III) ions in a distorted octahedral environment, CrN3O3, and the central metal ions M are six-coordinate, mostly trigonal prismatic, with the MN6 core. The crystal structures of the perchlorate salts of 7, 8, and 11 have been determined by single-crystal X-ray crystallography. They crystallize in the monoclinic system, space group C2/c with the following cell parameters:  7, a = 29.029(7) Å, b = 12.239(4) Å, c = 14.850(4) Å, β = 118.90(2)°, Z = 4; 8, a = 32.333(6) Å, b = 8.772(2) Å, c = 16.716(3) Å, β = 109.51(3)°, Z = 4; 11, a = 30.941(6) Å, b = 8.777(2) Å, c = 16.801(3) Å, β = 96.22(3)°, Z = 4. The structures consist of tris(dimethylglyoximato)-bridged CrIIIMIICrIII dications and noncoordinated perchlorate anions, with an intramolecular Cr···Cr distance of ∼7.1 Å. The trinuclear unit Cr−M−Cr is nearly planar exhibiting angles at M in the range 179.0−178.6°, except 7, with a Cr−Cu−Cr angle of 175.1°. Analysis of the susceptibility data indicates the presence of weak to moderate exchange interactions, both ferro- and antiferromagnetic, between the paramagnetic centers. There are indeed two different coupling constants, J (=J 12 = J 23) and J 13, operative in these clathrochelates. J 13 represents the exchange interaction between the two terminal Cr(III) centers separated by a large distance of ∼7.1 Å. An analysis of the interacting magnetic orbitals in complexes containing three metal centers is presented. The cyclic voltammograms of the complexes reveal both oxidation and reduction processes and indicate the formation of the uncommon species such as Cu(III), Ni(III), Ni(IV), and low-spin Fe(III). Liquid secondary ion mass spectrometry (L-SIMS) demonstrates the nonfragile character of the complexes examined, together with their nuclearity.

The local structure of the Au(111)(√3x√3)R30°-methylthiolate surface phase has been investigated by S K-edge near-edge X-ray absorption fine structure (NEXAFS) both experimentally and theoretically, and by experimental normal-incidence X-ray standing waves (NIXSW) at both the C and S atomic sites. NEXAFS shows not only excitation into the intramolecular * S-C resonance, but also into a * S-Au orbital perpendicular to the surface, clearly identifying the local S headgroup site as atop an Au atom.Simulations show that it is not possible, however, to distinguish between the two possible adatom reconstruction models; a single thiolate species atop a hollow-site Au adatom, or a dithiolate moiety comprising two thiolate species bonded to a bridge-bonded Au adatom. Within this dithiolate moiety a second * S-Au orbital that lies near-parallel to the surface has a higher energy that overlaps that of the * S-C resonance. The new NIXSW data show the S-C bond to be tilted by 61° relative to the surface normal, with a preferred azimuthal orientation in <211>, corresponding to the intermolecular nearestneighbour directions. This azimuthal orientation is consistent with the thiolate being atop a hollow-site Au adatom, but not consistent with the originally-proposed Au-adatomdithiolate moiety. However, internal conformational changes within this species could, perhaps, render this model also consistent with the experimental data.3

Although hair forms (straight, curly, wavy, etc.) are present in apparently infinite variations, each fibre can be reduced to a finite sequence of tandem segments of just three types: straight, bent/curly, or twisted. Hair forms can thus be regarded as resulting from genetic pathways that induce, reverse or modulate these basic curvature modes. However, physical interconversions between twists and curls demonstrate that strict one-to-one correspondences between them and their genetic causes do not exist. Current hair-curvature theories do not distinguish between bending and twisting mechanisms. We here introduce a multiple papillary centres (MPC) model which is particularly suitable to explain twisting. The model combines previously known features of hair cross-sectional morphology with partially/completely separated dermal papillae within single follicles, and requires such papillae to induce differential growth rates of hair cortical material in their immediate neighbourhoods. The MPC model can further help to explain other, poorly understood, aspects of hair growth and morphology. Separate bending and twisting mechanisms would be preferentially affected at the major or minor ellipsoidal sides of fibres, respectively, and together they exhaust the possibilities for influencing hair-form phenotypes. As such they suggest dialectic for hair-curvature development. We define a natural-dialectic (ND) which could take advantage of speculative aspects of dialectic, but would verify its input data and results by experimental methods. We use this as a top-down approach to first define routes by which hair bending or twisting may be brought about and then review evidence in support of such routes. In particular we consider the wingless (Wnt) and mammalian target of rapamycin (mTOR) pathways as paradigm pathways for molecular hair bending and twisting mechanisms, respectively. In addition to the Wnt canonical pathway, the Wnt/Ca(2+) and planar cell polarity (PCP) pathways, and others, can explain many alternatives and specific variations of hair bending phenotypes. Mechanisms for hair papilla budding or its division by bisection or fission can explain MPC formation. Epithelial-to-mesenchymal (EMT) and mesenchymal-to-epithelial (MET) transitions, acting in collaboration with epithelial-mesenchymal communications are also considered as mechanisms affecting hair growth and its bending and twisting. These may be treated as sub-mechanisms of an overall development from neural-crest stem cell (NCSC) lineages to differentiated hair follicle (HF) cell types, thus providing a unified framework for hair growth and development.

Banks in India face opportunities to innovate to meet changing expectations regarding green banking practices.

The structures of the high-coverage ('standing-up') and low-coverage ('lying-down') phases of butylthiolate on Au(111) have been investigated by a range of experimental methods. Normal incidence X-ray standing waves, photoelectron diffraction and near-edge X-ray absorption fine structure results all identify the local S headgroup site as atop a surface Au atom in a bulk continuation site for both high- and low-coverage phases. Low energy electron diffraction shows the low-coverage phase to have a (12 x radical 3)rect. surface mesh with glide-line symmetry (pmg space group), the long dimension of this mesh being approximately four times the length of the butylthiolate molecule. A structural model is proposed for this phase based on two different enantiomers of an Au-adatom-dithiolate species that is consistent with these results and with recent finding for propylthiolate on this surface using low-temperature scanning tunnelling microscopy (O. Voznyy, J. J. Dubowski, J. T. Yates Jr. and P. Maksymovych, J. Am Chem. Soc., 2009, 131, 12989).

A broad-spectrum 5-day regimen is superior to 'single-shot' antibiotic prophylaxis in preventing infection-related wound complications. However, this study needs to be conducted in a larger number of patients to have statistical power.