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A genetic algorithm (GA), driven by experimentally determined biological activities as a feedback fitness function, was used to propose novel small molecules as inhibitors of glucose-6-phosphate translocase (G6PT) in iterative rounds of evolutionary optimization. A straightforward polymer-supported synthetic sequence was implemented to synthesize molecules proposed by the GA, and the biological activities of the compounds were determined by a microsomal assay. Additional compound design strategies were integrated, such as Tanimoto similarity-based selection of starting materials and transfer of favored structure elements into a new chemical scaffold to identify more active and selective inhibitors.

Crystallization of amorphous Co-Zr is studied for compositions ranging from 7 to 14 at.% Zr using time-resolved small and large angle X-ray scattering. A time-transformation diagram is given for the composition range studied. A new metastable bcc-Co phase with 8 at.% dissolved Zr is found, which has a lattice constant of 2.845 Å, It forms upon quenching from the melt or by polymorphic crystallization of the amorphous alloy. Cooling the bcc-phase leads to a fast transformation. Within about 1 s, a semi-coherent structure is formed where the local concentration and lattice structure is modulated on a length scale of about 30 Å. During this transformation the local composition and crystal structure segregate to fee-Co and to Co23Zr6.

Time-resolved X-ray scattering has been used to study the kinetics of crystallization of amorphous metals on time scales varying from minutes to milliseconds. Measurements have been at the National Synchrotron Light Source, using a wide-bandpass monochomator and fast linear position-sensitive detector system at the IBM/MIT beamline X-20C. With this apparatus, scattering patterns from the transforming material can be acquired with 3-ms time resolution. A fast pyrometric temperature controller has been developed to change and regulate the sample temperature with microsecond response. In a typical measurement, two synchronized position-sensitive detectors provide complementaryin situ information about the transformation. The first is used for wide-angle scattering and allows us to determine which phases are present and to what extent. Changes in lattice parameter and particle size can also be deduced. The second detector measures small-angle scattering, yielding additional information about the microstructure, such as the spacing between lammellae in eutectic systems. At relatively slow transformation rates, quantitative measurements of crystal volume fractions as small as 10-4 are possible. In many systems, as the transformation rate is increased, the crystallization mechanism changes such that new metastable crystal phases are formed en route to the equilibrium structure.

Following recent evidence that brachial and femoral artery pressures are more reliable than radial artery pressures after cardiopulmonary bypass, thirty-one adults had simultaneous pre and post-bypass measurements of brachial, femoral, and ascending aortic pressures. Two minutes after cardiopulmonary bypass, brachial artery systolic pressure and mean arterial pressure fell significantly below corresponding pressures in the femoral artery and aorta. Five minutes after cardiopulmonary bypass, only brachial artery systolic pressure was still less than femoral and aortic systolic pressures. By ten minutes after bypass, all significant pressure differences had resolved except between brachial and femoral artery systolic pressures. Clinically significant (≥ 5 mmHg) aortic-to-brachial reductions in mean arterial pressures occurred in six (19%) patients at two minutes and in three (10%) patients at five and ten minutes after bypass. Equivalent aortic-to-femoral mean pressure diminution occurred in two (6%) patients at two minutes and one (3%) patient at five and ten minutes after bypass. Neither systemic vascular resistance nor body temperatures contributed significantly to post-bypass central-to-peripheral pressure reductions. Immediately following bypass, femoral artery pressures reproduce central aortic pressures more reliably than do radial or brachial artery pressures.

The structure–property relationships of a vintage ASTM A7 steel is quantified in terms of stress state, temperature, and strain rate dependence. The microstructural stereology revealed primary phases to be 15.8% ± 2.6% pearlitic and 84.2% ± 2.6 ferritic with grain sizes of 13.3 μm ± 3.1 μm and 36.5 μm ± 7.0 μm, respectively. Manganese particle volume fractions represented 0.38–1.53% of the bulk material. Mechanical testing revealed a stress state dependence that showed a maximum strength increase of 85% from torsion to tension and a strain rate dependence that showed a maximum strength increase of 38% from 10−1 to 103 s−1at 20% strain. In tension, a negative strain rate sensitivity (nSRS) was observed in the quasi-static rate regime yet was positive when traversing from the quasi-static rates to high strain rates. Also, the A7 steel exhibited a significant ductility reduction as the temperature increased from ambient to 573 K (300 °C), which is uncommon for metals. The literature argues that dynamic strain aging (DSA) can induce the negative strain rate sensitivity and ductility reduction upon a temperature increase. Finally, a tension/compression stress asymmetry arises in this A7 steel, which can play a significant role since bending is prevalent in this ubiquitous structural material. Torsional softening was also observed for this A7 steel.

An unusual case of painful fingers in a two-year-old child is described. The possible aetiolgy is discussed. The condition normally runs a self-limiting course.