Necrotising soft tissue infections are potentially fatal. Early recognition and prompt aggressive debridement are the keys to successful management.

X-ray-scattering measurements on TTF-TCNQ (tetrathiafulvalene-tetracyanoquinodimethane) above 54 K clearly reveal a new one-dimensional scattering at the wave vector (0.59±0.02)6* interpreted as 4fc F scattering and attributed to an additional phonon anomaly which also condenses at low temperature. This 4fc F scattering is still clearly visible at 220 K in contrast to the earlier reported 2fe F scattering which is found to disappear at 150 K in agreement with the neutron scattering results of Shirane et al %

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Elastic wave travel times have been determined as functions of hydrostatic pressure to 3 GPa for five modes of propagation in synthetic single‐crystal wüstite Feo.943O by ultrasonic phase comparison. The measured travel times, corrected for transducer‐bond phase shifts, constrain very accurately the zero‐pressure elastic moduli (GPa) and, for the first time, their first pressure derivatives (dimensionless) as follows: C11∶218.4, dC11/dP∶9.65, C12∶123.0, dC12/dP∶2.77, C44∶45.5, dC44/dP∶−1.03. The zero‐pressure moduli are in good agreement with the results of previous determinations by ultrasonic wave propagation but not with all of the moduli determined by resonance techniques. The variation of bulk modulus with pressure calculated from the Cij (P) is extrapolated to much higher pressures via third‐order Eulerian isotherms and isentropes based on K0S = 154.9 GPa and (dKs/dP)0T = 4.90. The resulting isothermal and shock compression curves satisfactorily reproduce the experimental data to ∼70 GPa, thereby providing a unified description of essentially all data bearing on the compressibility of wüstite. At higher pressures, published shock compression studies provide clear evidence for the existence of a different phase of much greater density and incompressibility. Metallic values of electrical conductivity have been reported for pressures >70 GPa under conditions of shock and high‐temperature static loading. Polyhedral face‐sharing in either the B8(NiAs) or B2(CsCl) (or derivative) structures would result in shorter Fe‐Fe distances, allowing greater 3d orbital overlap conducive to metallic conductivity. However, none of these possibilities satisfactorily accounts for the large inferred increase (14–20%) in zero‐pressure density unless the Fe‐O distance is also reduced by 3–5% by electron delocalization or spin‐pairing. The marked violation of the Cauchy condition associated with the very low value of C44 and its unusual temperature and pressure derivatives are attributable mainly to exchange coupling between nearest and next‐nearest neighbor spins.

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Inelastic electron tunneling spectroscopy is a useful technique for the study of vibrational modes of molecules adsorbed on the surface of oxide layers in a metal-insulator-metal tunnel junction. The technique involves studying the effects of adsorbed molecules on the tunneling spectrum of such junctions. The data give useful information about the structure, bonding, and orientation of adsorbed molecules. One of the major advantages of inelastic electron tunneling spectroscopy is its sensitivity. It is capable of detecting on the order of 10(10) molecules (a fraction of a monolayer) on a 1-square-millimeter junction. It has been successfully used in studies of catalysis, biology, trace impurity detection, and electronic excitations. Because of its high sensitivity, this technique shows great promise in the area of solid-state electronic chemical sensing.

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(TTF)Clx, x=0.67 and 0.70, is a quasi-one-dimensional organic conductor with a room temperature conductivity of ∼ 150 Ω−1 cm−1. At room temperature the structure is tetragonal and consists of chains of uniformly spaced, eclipsed TTF molecules surrounding channels occupied by chloride ions, which form a disordered structure. The chloride substructure becomes ordered and the TTF substructure undergoes a phase transition from tetragonal to monoclinic symmetry at ∼250 °K. The angle β of the monoclinic phase increases continuously as the temperature is decreased from 245 ° to 19 °K. The electrical conductivity shows a sharp decrease at the phase transition which is suggestive of the formation of commensurate charge density waves in the monoclinic phase.