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Evidence of exposure of a metal component to a small charge explosion can be detected by observing microstructural modifications; they may be present even if the piece does not show noticeable overall plastic deformations. Particularly, if an austenitic stainless steel (or another metal having a face-centered cubic structure and a low stacking fault energy) is exposed to an explosive shock wave, high-speed deformation induces primarily mechanical twinning, whereas, in nonexplosive events, a lower velocity plastic deformation first induces slip. The occurrence of mechanical twins can be detected even if the surface is damaged or oxidized in successive events. In the present research, optical metallography (OM) and scanning electron microscopy (SEM), and scanning tunneling microscopy (STM) were used to detect microstructural modifications caused on AISI 304Cu steel disks by small-charge explosions. Spherical charges of 54.5 or 109 g TNT equivalent mass were used at explosive-to-target distances from 6.5 to 81.5 cm, achieving peak pressures from 160 to 0.5 MPa. Explosions induced limited or no macro-deformation. Two alloy grain sizes were tested. Surface OM and SEM evidenced partial surface melting, zones with recrystallization phenomena, and intense mechanical twinning, which was also detected by STM and X-ray diffraction. In the samples' interior, only twins were seen, up to some distance from the explosion impinged surface and again, at the shortest charge-to-sample distances, in a thin layer around the reflecting surface. For forensic science locating purposes after explosions, the maximum charge-to-target distance at which the phenomena disappear was singled out for each charge or grain size and related to the critical resolved shear stress for twinning.

Developing countries face the double menace of still prevalent infectious diseases and increasing cardiovascular disease (CVD) with epidemic proportions in the near future, linked to demographic changes (expansion and ageing), and to urbanisation and lifestyle modifications. It is estimated that the elderly population will increase globally (over 80% during the next 25 years), with a large share of this rise in the developing world because of expanding populations. Increasing longevity prolongs the time exposure to risk factors, resulting in a greater probability of CVD. As a paradox, increased longevity due to improved social and economical conditions associated with lifestyle changes in the direction of a rich diet and sedentary habits in the last century, is one of the main contributors to the incremental trend in CVD. The variable increase rate of CVD in different nations may reflect different stages of "epidemiological transition" and it is probable that the relatively slow changes seen in developing populations through the epidemiological transition may occur at an accelerated pace in individuals migrating from nations in need to affluent societies (i.e. Hispanics to the USA, Africans to Europe). Because of restrained economic conditions in the developing world, the greatest gains in controlling the CVD epidemic lies in its prevention. Healthy foods should be widely available and affordable, and healthy dietary practices such as increased consumption of fresh fruits and vegetables, reduced consumption of saturated fat, salt, and simple sugars, may be promoted in all populations. Specific strategies for smoking and overweight control may be regulation of marketed tobacco and unhealthy fast food and promotion of an active lifestyle. Greater longevity and economic progress are accompanied by an increasing burden of CVD and other chronic diseases with an important decrease in quality of life, which should question the benefit of these additional years without quality.

During melting and solidification of polycrystalline indium the structures of the solid and liquid phases were investigated by X-ray diffractometry (XRD) in 1g conditions. The experiments showed that melting is immediately preceded and accompanied by an abnormal increase of vacancy concentration in the solid that enhances the diffusion. At the melting point (T(M)) the lattice planes facing the first formed liquid appear to be [002] and [101]; that is, those planes allocating first and second neighbors around a given atom, with shell radii very close to the mean distance of nearest neighbors in liquid as obtained from the radial distribution function (RDF). On this basis some types of solid-liquid interface (sharp or diffuse) are discussed; the possibility of a sudden texture change in the solid is also considered. On the other hand, the evolution of RDF curve of liquid indium, cooled down through T(M), shows that there are correlations between the structure of the liquid and of the forming solid during solidification. To avoid convective motions in the liquid and to achieve the best experimental conditions, we discuss the possibility of repeating the measurements in microgravity (microg) using thin oxide films as containers. This technique was already successfully tested by one of the investigators in the experiment ES 311 A-B carried out during the mission SPACELAB-1.

We present an analytical continuous equation for the Tang and Leschhorn model [Phys. Rev. A 45, R8309 (1992)] derived from their microscopic rules using a regularization procedure. As well in this approach, the nonlinear term (nablah)(2) arises naturally from the microscopic dynamics even if the continuous equation is not the Kardar-Parisi-Zhang equation [Phys. Rev. Lett. 56, 889 (1986)] with quenched noise (QKPZ). Our equation is similar to a QKPZ equation but with multiplicative quenched and thermal noise. The numerical integration of our equation reproduces all the scaling exponents of the directed percolation depinning model.

Wilson's disease is a rare inherited metabolic disorder usually characterized by liver and/or neurological degeneration. Unlike most genetically transmitted diseases, it rapidly responds to pharmacological treatment in case of early diagnosis and treatment. Often, however, as this disease presents with aspecific symptoms, patients are wrongly diagnosed as psychiatric cases or as having generic chronic liver disease and the true cause of symptoms is only discovered at a much later stage. The authors give a detailed review of the literature with the aim of presenting the most recent research on the main aspects of this disease and offering a practical and simple approach to early diagnosis.

In order to investigate the nature of impaired glucose tolerance (IGT) in 3 young patients with Graves' disease we have studied their insulin secretion fasting and in response to oral glucose by means of measurement of serum C-peptide. Fasting levels of serum C-peptide of these patients were beyond the range of 15 age-matched normal subjects; the C-peptide/glucose ratio was also significantly higher (p less than 0.001) in the patients than in the controls. Following glucose ingestion serum levels of C-peptide resulted high in the range of normals, with a mean C-peptide/glucose ratio greater than in the controls, but without reaching of statistical significance. To investigate whether the anomaly in fasting insulin secretion of these patients had any correlation with their hyperthyroidism, afterwards we surveyed fasting concentrations of serum C-peptide in parallel with progressive variations of serum free thyroxine and triiodothyronine (FT4 and FT3) and thyrotrophin (TSH) during antithyrotoxic treatment with methimazole. The data of 23 tests on serum FT3 and FT4 levels, carried out during 16-18 months, resulted in significant correlation with contemporaneous measurements of fasting serum C-peptide (p less than 0.001). No significant correlation was found between serum TSH and fasting C-peptide levels. The results suggest that IGT of the patients in this study is not dependent on lacking insulin secretion, but on mild insulin resistance. Such glucose metabolic anomaly appears to be in clear correlation with the degree of hyperthyroidism, even if its pathogenesis remains to be further investigated.

Seventeen elderly patients are described, who showed minor changes in the e.c.g. recovery phase. Serum potassium levels appeared to be normal, but red-blood-cell potassium was found to be more or less markedly reduced. Restoration of the latter to normal values, which followed treatment with potassium salts was also associated with normalization of the e.c.g. pattern. These observations demonstrate that electrolyte disorders, and particularly hypokalaemia, may determine 'minor' alterations of repolarization much more frequently than is usually thought, and that determination of serum potassium levels is not a reliable tool for detecting potassium depletion, which is more accurately reflected by red-blood-cell potassium concentration.

Ferritin (F) is an iron-protein (molecular weight 445.000) present in various organs including the heart. Using the immunoenzymatic method (Ferrizyme Abbott), ferritinemia (Fe) was determined daily in 28 patients with acute myocardial infarction (AMI). A significant rise was revealed, already evident in the first few days 8-9 after with Fe gradually returns to baseline levels. The results have shown that this pattern is not evident in patients with angina, heart failure, valve defects, pericarditis or cor pulmonale and may thus be considered a reliable, if not early, marker of myocardial cytolysis. In those cases studied no correlations were observed between CPK and Fe peak or between these and clinical intensity of AMI.

The authors evaluated the existence of serum thyroid microsomal antibodies (anti-TMS) and their correlation, if any, with thyroid function in a group of 120 consecutive patients, who seemed clinically worthy to be studied from that point of view, even if they were lacking of a previous laboratory framing. Present study shows a consistent prevalence (81.8%) of anti-TMS concentrations were not related with any hormone parameter of thyroid function. Instead, the prevalence of anti-TMS positive subjects get to 69% in the 39 over-65 aged patients (32 women) of survey, with a concordance between high anti-TMS concentration and hypothyroidism of 87.5% in the subgroup. In these elderly patients circulating anti-TMS and serum TSH were found directly correlated (p less than 0.001), whereas serum FT4 was found in inverse correlation with the same antibodies (p less than 0.01). The consistent share of hypothyroid-aging patients, although mild or subclinical but clearly related with immunological phenomena, cannot be overlooked.