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Presents a study which examined data on eclogites from the Glenelg-Attadale Inlier in Northwest Scotland. Geological setting; Chronology of the Glenelg eclogites; Results and discussion.

Conditions are established under which polynomial system matrices over R[s, z] are strictly system equivalent over R[s, z]. A counter-example is given to a more general result.

Matrices over R[s, z] which are extensions of the usual form of state-space system matrices over R[s] are considered, the main object being to investigate under what conditions such matrices are system similar over R[z]. It is found that these conditions involve not only the concept of decoupling factors of a system matrix over R[s, z] but also the new concept of decoupling zeros of such a system matrix. The connection of these decoupling zeros for a given system matrix with the corresponding transfer-function matrix is also examined.

Descent property and global convergence proofs are given for a new hybrid conjugate gradient algorithm. Computational results for this algorithm are also given and compared with those of the Fletcher-Reeves method and the Polak-Ribière method, showing a considerable improvement over the latter two methods. We also give new criteria for restarting conjugate gradient algorithms that prove to be computationally very efficient. These criteria provide a descent property and global convergence for any conjugate gradient algorithm using a nonnegative update ß.

In this paper, low-order Newton methods are proposed that make use of previously obtained second-derivative information by suitable preconditioning. When applied to a particular 2-dimensional Newton method (the LS method), it is shown that a member of the Broyden family of quasi-Newton methods is obtained. Algorithms based on this preconditioned LS model are tested against some variations of the BFGS method and shown to be much superior in terms of number of iterations and function evaluations, but not so effective in terms of number of gradient evaluations.

Conjugate gradient optimization algorithms depend on the search directions,

Depletion of high-energy phosphates, accumulation of inorganic phosphate and intracellular acidosis have each been proposed as important events in the transition from reversible to irreversible ischemic injury. To assess whether each variable is predictive of functional recovery on reperfusion, these were measured in the isolated isovolumic rat heart using31P NMR. Perfused hearts were subjected to either 10, 12 or 40 min of normothermic ischemia followed by 40 min of reperfusion. Hearts were then freeze-clamped for further analysis of phosphate metabolites by NMR and ion chromatography. High-energy phosphates, Pi, phosphomonoesters and pH were measured by31P NMR spectroscopy at 2 minute intervals. Heart rate and developed pressure were monitored simultaneously. All hearts undergoing 10 min of ischemia and 40% of hearts subjected to 12 min of ischemia demonstrated good functional recovery. The remainder of hearts ischemic for 12 min went into contracture on reperfusion with little return of function. Hearts subject to 40 min of ischemia went into ischemic contracture and showed no recovery on reperfusion. Intracellular pH, [ATP], and [Pi] measured prior to reperfusion did not predict the extent of recovery. However, phosphomonoesters were detected prior to reperfusion in all hearts that did not recover well, but were not observed in hearts that showed good mechanical recovery. Analysis of tissue extracts by31P NMR and ion chromatography indicated that the most prominent components of the phosphomonoesters were glucose 6-phosphate, a-glycerol phosphate and AMP. In conclusion, of the various phosphorus metabolites that can be measured by31P NMR, only one group, the phosphomonoesters, was predictive of functional recovery.

A new approach to the determination of the domain of attraction of ordinary differential equations is applied to power systems taking into account constant damping and no saliency, constant damping and saliency, and variable damping and saliency. The results are compared with the conventional methods and are found to give a better estimate of the stability boundary. A model which includes the effects of constant damping and the velocity governor is also studied. In this third-order system, cross-sections of the stability surface for the principal planes are given, again showing the superiority of the method.

The sensitivity and specificity of an immune dot blot test (IDBT), which relies on a 125I-labeled genus-specific monoclonal antibody to detect the Chlamydia lipopolysaccharide (LPS) antigen, were improved by pretreatment of specimens with proteinase K. This enzyme destroys protein A and therefore eliminates false-positive reactions caused by the presence of Staphylococcus aureus. Proteinase K treatment also improved the ability of the assay to detect the Chlamydia LPS antigen. When the improved IDBT was compared with culture for detection of C. trachomatis in 1,394 urogenital specimens obtained from a genitourinary medicine clinic, the overall sensitivity was 96%, and LPS antigen was detected in 76 of 83 (92%) specimens that yielded less than 10 inclusions in culture. The specificity and positive and negative predictive values of the test were 97, 81.5, and 99%, respectively. Of 123 conjunctival swabs, 7 were positive by both tests and 4 swabs were positive only by IDBT. This improved IDBT provides a simple, reliable alternative to culture for the detection of C. trachomatis in urogenital and conjunctival specimens.

We describe global optimization problems from three different fields representing many-body potentials in physical chemistry, optimal control of a chemical reactor, and fitting a statistical model to empirical data. Historical background for each of the problems as well as the practical significance of the first two are given. The problems are solved by using eight recently developed stochastic global optimization algorithms representing controlled random search (4 algorithms), simulated annealing (2 algorithms), and clustering (2 algorithms). The results are discussed, and the importance of global optimization in each respective field is focused.

An immune dot blot test (IDBT) to detect the genus specific lipopolysaccharide chlamydial antigen is described, in which the antigen is trapped on nitrocellulose membrane and then detected with a monoclonal antibody labelled with 125iodine. A preliminary comparison of 270 specimens obtained from the endocervix or male urethra showed that the IDBT was more sensitive (sensitivity 90%) than a commercial amplified enzyme immunoassay named IDEIA (sensitivity (60%) for detecting specimens that yielded Chlamydia trachomatis on culture. Subsequent assessment of 950 urogenital tract specimens in the IDBT and by culture confirmed the sensitivity (92%) and specificity (95%) of the IDBT. At least one of 56 specimens obtained from the eye, however, gave a false positive result, which was probably due to staphylococcal protein A in the specimen. The IDBT provides the basis for a novel simple test for detecting the genus Chlamydia. [ABSTRACT FROM PUBLISHER]

ATRESIA and stenosis of the colon are the rarest of all congenital narrowings of the gastrointestinal tract. Although this paper is concerned chiefly with congenital stenosis of the colon, these lesions are so clearly related to similar occlusions elsewhere in the intestinal tract in the matter of symptomatology, therapy, and probable etiology that reference to allied disorders situated elsewhere in the bowel can scarcely be avoided. Congenital intestinal atresia and stenosis are associated with a high mortality, but considering this group of developmental abnormalities as a whole, one finds reports of an increasing number of successfully treated patients appearing in the literature. These successes, all resulting from wisely chosen, properly timed, and carefully executed surgical procedures, have enhanced the importance of an early diagnosis for infants suffering with defects of this type. Prompt recognition of the obstruction and early surgical relief offer the only hope for a favorable outcome. As

Décrire le dépistage et le suivi par imagerie des sujets asymptomatiques porteurs d’une mutation sur SDHB, SDHC ou SDHD dans 6 centres français.

Les syndromes lipodystrophiques sont des maladies rares caractérisées par un déficit en tissu adipeux et par des troubles métaboliques associant insulino-résistance, dyslipidémie et stéatose hépatique, avec un retentissement ovarien chez les femmes. Ils regroupent de nombreuses formes cliniques, la lipoatrophie étant généralisée ou partielle, d’origine génétique ou acquise, révélée à l’âge pédiatrique ou chez l’adulte, et accompagnée ou non d’autres co-morbidités, en particulier cardio-vasculaires. Les syndromes lipodystrophiques sont probablement largement sous-diagnostiqués.