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The spectacular kilometer‐thick Funzie Conglomerate is a deformed and metamorphosed high‐energy sedimentary deposit that occurs in Shetland (Scottish Caledonides). Its age and tectonic significance in relation to Early Ordovician (485–475 Ma) and Late Ordovician (450–445 Ma) accretionary orogenic events and the culminating Silurian (430–425 Ma) continental collision and closure of the Iapetus Ocean have hitherto been unknown. U‐Pb zircon dating indicates that the clast population of the conglomerate was derived from easterly sources comprising Neoproterozoic metasedimentary rocks and the northern extension of the Ordovician‐Silurian Midland Valley Arc that formed during Iapetus closure. A lower age limit of 440 Ma is indicated by the ages of the youngest matrix detrital zircon grains and the youngest granitic clast. Deformation and metamorphism of the conglomerate is attributed to sinistrally oblique extension at ca. 430 Ma that excised at least 10 km of crustal section. Sedimentation of the conglomerate is therefore constrained to a 10‐myr time span (440–430 Ma). The tectonic setting is interpreted as a synorogenic basin that received detritus from, and was buried by, advancing thrust nappes during the Early Silurian collision of Laurentia and Baltica. Tectonic burial was followed rapidly by ductile deformation during oblique extensional unroofing of the metamorphic pile and accounts for preservation of the Funzie Conglomerate as a rare example of a synorogenic basin within the metamorphic hinterland of the North Atlantic Caledonides. U‐Pb zircon dating in combination with published mineral age data shows that the deformed and metamorphosed Funzie Conglomerate in Shetland, Scottish Caledonides, was deposited in the Early Silurian between ca. 440 and 430 MaThe clast population was derived from easterly (offshore) sources comprising Neoproterozoic metasedimentary rocks and the northern extension of the Ordovician Midland Valley Arc that formed during closure of the Iapetus OceanThe tectonic setting is interpreted as a synorogenic basin that received detritus from, and was buried by, advancing thrust nappes during the collision of Laurentia and Baltica

Le ganglioneurome (GN) est une tumeur neuroblastique différenciée, rare, issue du système nerveux sympathique périphérique. Il se développe aux dépens de la glande surrénale dans 20 à 25 % des cas. L’objectif de cette étude est de caractériser les GN surrénaliens et d’étudier le risque de récidive après chirurgie.

The article presents information on acutonics. It is a transformational and inherently coherent system of Sound Healing, that incorporates the use of tuning forks in conjunction with or in place of Acupuncture needles. It incorporates teachings of the meridians, the pre-meridians and the immortal body of the ancient Taoist. This system provides a comprehensive methodology that is rooted in Oriental Medicine, Music Theory and the Vibrations of Planetary Ecosystem. Acutonics can balance the physical body, but it has the direct ability to re-awaken a deep appreciation for the whole Earth Body. Acutonics is the embodied art of the Music of the Spheres, made possible through modern day metallurgic technology.

In this note, a general optimal conditioning problem for updates which satisfy the quasi-Newton equation is solved. The new solution is a family of updates which contains other known optimally conditioned updates but also includes new formulas of increased rank. A new factorization formula for the Broyden family and some preliminary numerical results are also given.

The effect of inexact line search on conjugacy is studied in unconstrained optimization. A generalized conjugate gradient method based on this effect is proposed and shown to have global convergence for a twice continuously differentiable function with a bounded level set.

In Part 1 of this paper (Ref. 1), a new, generalized conjugate gradient algorithm was proposed and its convergence investigated. In this second part, the new algorithm is compared numerically with other modified conjugate gradient methods and with limited-memory quasi-Newton methods.

A new generalized Polak-Ribière conjugate gradient algorithm is proposed for unconstrained optimization, and its numerical and theoretical properties are discussed. The new method is, in fact, a particular type of two-dimensional Newton method and is based on a finite-difference approximation to the product of a Hessian and a vector.

Abstract: An algorithm for unconstrained minimization is developed which uses a rational function model, rather than a quadratic, as a basis for conjugate directions. The algorithm is similar to one previously proposed by the authors, but inexact linear searches are investigated in the present paper.

Abstract: In this paper, a new variable-metric method based on a rational, rather than a quadratic, model is proposed. A switching algorithm is also introduced which selects either the standard quadratic model or the new rational model, depending on which has the smallest condition number. Several functions are used to test the new method, and it is concluded that it is as efficient as the standard model in general and is superior for problems of high dimensionality. Considerable improvement is also obtained for high-dimensional problems when the switching algorithm is used.

Abstract: A conjugate-gradient method for unconstrained optimization, which is based on a nonquadratic model, is proposed. The technique has the same properties as the Fletcher-Reeves algorithm when applied to a quadratic function. It is shown to be efficient when tried on general functions of different dimensionality.

We have recently developed a new conjugate gradient type method, the Generalized Polak-Ribière (GPR) method, for unconstrained minimization. It is based on search directions that are parallel to the Newton direction of the restriction of the objective function f on the two dimensional subspace span{-gp}, with p a suitable direction in span{- g,s-}, where g and s- are the current gradient and previous search direction respectively. The new approach proved to be considerably more efficient than the original Polak-Ribière method.In this paper, various implementations of the GPR method are compared with a currently available standard NAG software routine and also with the Nocedal, Buckley-LeNir and Shanno's limited memory algorithms. The results demonstrate the general effectiveness of the new algorithm. We also give a very brief discussion of extensions of the GPR method that generate search directions parallel to Newton directions in subspaces of dimension greater than two.

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.

Several types of controllability have been defined for linear constant delay-differential systems. Certain necessary and sufficient conditions involving a form of ' controllability matrix ' for these systems are investigated. Particular reference is made to the concept of Rn-controllability.

Conditions under which a matrix over R[s, z] is equivalent, to its Smith form are investigated. These conditions involve the concept of zeros of a matrix over R[s, z] which has not been previously encountered in this context.

This paper explores the problem of maximizing the size of a region of asymptotic stability (RAS) over a class of Lyapunov functions (LF) in order to estimate the domain of attraction of a continuous or discontinuous (relay) system. Analytic and numerical evidence shows that a subclass of LF may exist with multiple-tangency for the RAS problem, and can cause some serious convergence problems. Several systems are considered with two classes of LF for continuous and one class for relay systems.

An iterative topographical Multilevel Single Linkage (TMSL) method has been introduced. The approach uses topographical information on the objective function, in particular theg-nearest-neighbour graph. The algorithm uses evenly distributed points from a Halten sequence of uniform limiting density. We discuss the implementation of the algorithm and compare its performance with other well-known algorithms. The new algorithm performs much better (in some cases several times) than the Multilevel Single Linkage method in terms of number of function evaluations but is not quite so competitive with respect to CPU time.

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.

An aspiration based simulated annealing algorithm for continuousvariables has been proposed. The new algorithm is similar to the one givenby Dekkers and Aarts (1991) except that a kind of memory is introduced intothe procedure with a self-regulatory mechanism. The algorithm has beenapplied to a set of standard global optimization problems and a number ofmore difficult, complex, practical problems and its performance comparedwith that of the algorithm of Dekkers and Aarts (1991). The new algorithmappears to offer a useful alternative to some of the currently availablestochastic algorithms for global optimization.

Some modifications are suggested to the controlled random search algorithm for global optimization. Numerical experiments indicate that the resulting algorithms are considerably better than the originals and offer a reasonable alternative to many currently available stochastic algorithms, especially for problems requiring 'direct search' type methods.

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.

Some first and second-order algorithms for solving certain types of non-linear distributed parameter optimal control problems are described. These are based on the conditions necessary for optimality. The different algorithms are applied to three specific problems, one of these being parabolic and the other two first-order hyperbolic. Results are compared for each problem and the different methods are discussed.

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

Previous work on the sensitivity of optimal linear control systems x˙ = Ax + Bu with quadratic performance index has concentrated on the effects of small changes in parameters. It is shown in this paper that the optimal feedback law u = - Dx is insensitive to (i.e. is unaltered by) a wide variety of persistent changes in A and B. Some explicit expressions for these variations in A and B are presented, including the cases when B is fixed, and when the change in A is known. If A is fixed any change in B results in a change in D, so that the system is more sensitive to changes in B than in A.

The results of a numerical investigation of a number of techniques for stability analysis of non-linear systems are presented. The methods compared are the Ingwerson and Zubov procedures for construction of Liapounov functions, a number of methods for obtaining optimum Liapounov functions, tracking functions, the alternating extreme radius path, and the method of Luus and Lapidus.

Methods due to Undrill and to Burnett and Storey for calculating MacFarlane's generalized functional matrix are critically compared. A comparison is also made with a method of Bass and Webber for finding the optimal feedback control in the case of linear systems with higher than quadratic indices.

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.

This note discusses a generalization of the trapezoidal method for numerical integration of the differential equations of the orthogonal trajectories of a function as a means of finding maximum or minimum values of the function. Connections between the choice of a parameter in the integration scheme and various modifications of Newton's method are indicated.

The Zubov and Ingwerson procedures for constructing Lyapunov functions depend upon an initial choice of some function of the state variables. A direct search procedure is described for obtaining the optimum function, and hence the Lyapunov function of an arbitrary order which gives the best estimate of the region of asymptotic stability. The method is illustrated by an example.

La période néonatale représente une fenêtre d’expression temporelle et tissu-spécifique des voies de signalisation corticostéroïdes. À la naissance, l’expression rénale et cérébrale du récepteur minéralocorticoïde (MR) et de la 11 b-hydroxystéroïde déshydrogénase de type 2 (qui métabolise les glucocorticoïdes) est transitoirement effondrée alors que le récepteur glucocorticoïde (GR) est présent et activé dans ces tissus. Inversement, l’expression pulmonaire du MR reste stable et celle du GR augmente au cours du développement, interrogeant sur la signification physiopathologique de ces variations.