Using acoustic logging data, we develop a method of estimating the horizontal shear modulus C66) of a transversely isotropic formation with its axis of symmetry parallel to that of the borehole. The data for the inversion are the wavenumbers, at every frequency, of the guided waves. The inversion minimizes the difference between these observed wavenumbers and those calculated by a forward model...

The antimitotic marine macrolide altohyrtin A/spongistatin 1 has been synthesised in a highly convergent and stereocontrolled manner, thus contributing to the replenishment of the largely exhausted material from the initial isolation work. Coupling of the AB- and CD-spiroacetal subunits by a stereoselective aldol reaction was achieved by using either a lithium (67 : 33 dr) or boron enolate (90 ...

Research on the implications of learning-by-doing has typically been restricted to specifications of the agent's decision problem for which estimation and control can be treated separately. Recent work has provided the limit properties of beliefs and actions for learning problems under more general conditions, for which experimentation is an important aspect of optimal control. However under th...

Risk managers are increasingly required by international Regulatory Institutions to adopt accurate techniques for the measurement and control of portfolios financial risks. The task requires first the identification of the different risk sources affecting the portfolio and the measurement of their impact, then after: the adoption of appropriate portfolio strategies aimed at neutralising these r...

The title compound, poly[bis-(μ(3)-4-acetamido-propane-sulfon-ato)-calcium], [Ca(C(5)H(10)NO(4)S)(2)](n), is a triclinic polymorph of the previously reported monoclinic structure [Toffoli et al. (1988 ▶). Acta Cryst. C44, 1493-1494]. The triclinic modification was found to have an all-trans configuration of the acetamido-propane chain, in contrast with the monoclinic polymorph which shows an an...

The electronic structures, densities of states, Fermi surfaces and elastic properties of AB3 (A =La, Y; B =Pb, In, Tl) compounds are studied under pressure using the full-potential linear augmented plane wave (FP-LAPW) method within the local density approximation for the exchange-correlation functional and including spin-orbit coupling. Fermi surface topology changes are found for all the isos...

Pediocin PA-1 is an antimicrobial peptide (called bacteriocin) that shows inhibitory activity against the food-borne pathogen Listeria monocytogenes. To elucidate which residue(s) is responsible for this function, the antimicrobial activities of pediocin PA-1 mutants were evaluated and compared. Each of the 44 native codons was replaced with the NNK triplet oligonucleotide in a technique termed...

Smart composites, manufactured with embedded functional materials, hold the potential for a new type of structural health monitoring systems. The work herein focuses on how embedding Ni43Co7Mn39Sn11 metamagnetic shape memory alloy (MMSMA) sensory particles into pure aluminum matrix modifies chemical constitution and mechanical properties both materials. Martensitically transforming in Al or all...

One of the most efficient non-destructive techniques for finding hidden faults in a plate is the use of ultrasonic Lamb waves. These waves are reflected by faults, and from this reflection, we can locate the faults. For that, we need to know how the Lamb waves propagate. Their propagation is determined by the dynamic elastic constants C 0 pq , so we must find these constants. These constants ca...