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Abstract  In this paper we present an application of the algorithm of the cyclic coordinate descent in multidimensional variational problems with constrained speed, the physical motivation of the problem being the optimization of hydrothermal systems. The proof of the convergence of the succession generated by the algorithm was based on the use of an appropriate adaptation of Zangwill’s global theorem of convergence. We have also included an algorithm for the formal construction of the descending succession (the solution of an optimum control problem), the approximation of which we carried out using an adaptation of the Euler method in conjunction with a procedure inspired by the shooting method. [ABSTRACT FROM AUTHOR]

This paper presents an environmental dispatch algorithm in a hydrothermal system and addresses the problem of minimization of emissions of SO2 and NOx caused by the operation of thermal plants. Several models have been used to represent the emissions function. In this paper, we first construct a quadratic model for both emissions: E(P)=α+β P+γ P2, where P is the power generated and the parameters were computed via the least-square criteria from several tests at thermal plants. We shall see that the problem consists in the minimization of a functional F(z) within the set of piecewise C1 functions that satisfy boundary conditions and non-holonomic inequality constraints. An optimal control technique is applied and Pontryagin’s theorem is employed. The algorithm proposed is easily implemented using the Mathematica Package and is applied to a sample system to illustrate the results obtained. [ABSTRACT FROM AUTHOR]

Cuttings of five Populus alba clones (S18 F1-26, Al29 F8-35, J3 F1-4, GU1 F16-36, PO9 F21-88), Populus euphratica, and Populus×euramericana (I-214) were submitted during 45 d to regular watering with NaCl solutions of electrical conductivity of 7 and 14 dS m−1. Chlorophyll a fluorescence in response to the salinity stress was assessed, using F0 and Fv/Fm. Differences in reaction to the salt were found in P. alba clones, F0 and Fv/Fm being the fluorescence parameters used to check out this stress. Minimal constant fluorescence of dark-adapted plants (F0) showed a better correlation with the disease index exhibited by plants and also with salinity dose than the parameter Fv/Fm. Some of the P. alba clones showed the same behaviour, assessed through fluorescence parameters, as P. euphratica, which was previously defined as salt tolerant, while the rest exhibited the same characteristics as I-214, which was very sensitive. [ABSTRACT FROM AUTHOR]

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zusammenfassung der morbus fabry ist eine x-chromosomal vererbte, lysosomale stoffwechselerkrankung, die auf einem mangel des enzyms α-galaktosidase a beruht und mit einer pathologischen sphingolipidspeicherung vor allem in endothel, glatter gefäßmuskulatur, nierenparenchym, zentralem und peripherem nervensystem und myokard einhergeht. die krankheit manifestiert sich vorwiegend in kindheit oder adoleszens mit attackenförmigen oder anhaltenden akrodistal betonten schmerzen, hypohidrose und hautveränderungen (angiokeratome). im weiteren verlauf stehen renale und zerebrovaskuläre manifestationen im vordergrund in form von proteinurie und später niereninsuffizienz sowie zerebralen ischämien, die auf einer mikroangiopathie, daneben auf einer dilatativen arteriopathie oder kardialen embolien beruhen. heterozygote überträgerinnen sind häufiger und stärker betroffen als lange angenommen. zur diagnose ist der nachweis einer defizienten α-galaktosidase-aktivität in leukozyten, fibroblasten oder gewebebiopsaten erforderlich. seit kurzem stehen zwei enzymersatzpräparate zur verfügung, deren zulassung auf randomisierten, plazebokontrollierten studien beruht, die schmerzminderung beziehungsweise eine reduktion pathologischer sphingolipidablagerungen im gewebe zeigten. angesichts kausaler therapiemöglichkeiten ist eine frühe diagnosestellung heute besonders wichtig. summary fabry''s disease is an x-linked, recessive, lysosomal storage disorder that results from deficient α-galactosidase a activity with pathological sphingolipid deposition mainly in endothelium, smooth muscle cells, kidneys, central and peripheral nervous system, and myocardium. clinical manifestation mostly occurs during childhood and adolescence with severe pain attacks or chronic pain mainly in hands and feet, hypohydrosis, and skin lesions (angiokeratoma). in more advanced disease stages, renal and cerebrovascular complications develop with proteinuria and later renal failure and cerebral ischemia caused by cerebral microangiopathy, dilatative arteriopathy, or cardiac embolism. heterozygote female carriers are severely affected more often than was previously considered. the diagnosis is based on the detection of deficient α-galactosidase a activity in leukocytes, fibroblasts, or tissue biopsies. two randomised placebo-controlled studies showed that enzyme replacement is effective by demonstrating either reduced pain or reduced tissue sphingolipid deposition. early diagnosis of fabry''s disease is important in view of these new causal therapeutic options. [ABSTRACT FROM AUTHOR]

Zusammenfassung Eine 37-jährige Patientin wurde wegen eines akuten Arteria-cerebri-media-Infarktes bei linksseitiger Arteria-carotis-interna-Dissektion stationär aufgenommen.Neun Tage zuvor hatte sie nach 20-stündiger, erfolgloser Wehentätigkeit mittels Kaiserschnitt entbunden. Die übrigen hirnversorgenden Arterien waren bei Aufnahme angiographisch unauffällig. Während des stationären Aufenthaltes in unserer Klinik entwickelte die Patientin zusätzlich Dissektionen der rechten Arteria carotis interna und beider Arteriae vertebrales. Zu den Dissektionen können sowohl Schwangerschaft und Geburt als auch eine rheumatoide Arthritis in der Vorgeschichte beigetragen haben, aufgrund der noch unklaren Ursache zervikaler Dissektionen ist der pathogenetische Anteil dieser Faktoren jedoch nicht genau zu beziffern. Summary A 37-year-old woman suffered from middle cerebral artery infarction secondary to dissection of the left internal carotid artery.Nine days before, a cesarean section had been performed on her after 20 h of unsuccessful labor.Cerebral angiography at admission revealed no further vascular abnormalities.A few days later,however, the patient developed additional dissections of the right internal carotid artery and both vertebral arteries. Pregnancy, childbirth, and a history of rheumatoid arthritis in this patient may have contributed to the dissections;however,due to the unknown etiology of cervical dissections, the pathogenetic contribution of all of these factors is incompletely understood. [ABSTRACT FROM AUTHOR]

An abstract of the article ""Sink or Swim": Riding the Waves to a Successful RRT," by E. Evangelista, J. Grau, J. Prata, B. Gill, L. Gebrian, C. Ritter, L. Dechant, K. Johnson and M. Seckel is presented.