Search

Ship autopilot technology has progressed considerably since the sixties. However most existing autopilots are mainly heading control autopilots. The availability of new positioning systems such as the Global Positioning System (GPS) and the possibility to obtain precise position thanks to Differential GPS opens the way to a new generation of autopilots: track keeping autopilots which would enable the ship to follow precisely a predefined path. The Port of Bordeaux has undertaken with the help of the University of Bordeaux the development of an autonomous surface vehicle (NAUSICAA) to serve as a platform for hydrographic data acquisition. This paper describes the general architecture of NAUSICAA and focuses on the design of the control system. Results obtained in June 95 from actual trials on the Garonne River are presented.

Although work in Remotely Operated Vehicles (ROV) and Autonomous Underwater Vehicles (AUV) has already led to the development of many vehicles, surface robots have not yet been designed. The Port of Bordeaux Authority has undertaken the development of such an autonomous surface vehicle. The primary objective of this craft is to serve as a platform for hydrographic data acquisition. The Autonomous Survey Vehicule (ASV) is a small autonomous surface craft. Navigation is monitored by a DGPS positioning system. The progress of the ASV is tracked by a Mobile Control Station which can either remain on-shore or be placed on-board a mother ship. This paper describes the general architecture of the ASV focusing on the identification process and on the development of the track keeping control system. LQG methods are used for design of the controller.

The state of the art in the family of radio-frequency ion thrusters called RIT is discussed. The R D programs involved in these thrusters are reviewed, and the mode of operation of the RIT thrusters is described. The thruster hardware is examined, including the North-South Stationkeeping thrusters RIT 10 and RIT 15 and the primary propulsion thruster RIT 35. 22 refs.

In 48 patients (age 2-28 years) with documented cystic fibrosis, glucose tolerance was evaluated by means of an oral glucose tolerance test (OGTT) and repeated glycosylated haemoglobin (HbA1C) measurements. An impaired OGTT was found in 15 patients. Their degree of undernutrition and severity of lung and liver involvement were no different from those with normal glucose tolerance. The mean peak insulin concentration as well as the integrated insulin concentration during the OGTT were comparable with patients with normal glucose tolerance (GT) and those with an impaired tolerance (GI). The mean time to attain peak insulin levels was significantly delayed in the GI group. (117 min vs 86 min P less than 0.01). On initial testing, elevated HbA1C levels were found in 22 patients. Mean HbA1C levels in the GI group were higher than in the GT group (8.2% vs 7.5% P less than 0.01). The HbA1C levels at the moment of OGT testing were positively correlated with the glycaemic response during the OGTT. The repeated HbA1C measurements 1 year later were no different from the initial mean HbA1C values in both groups. Two GI patients with initial HbA1C levels of 7.5% and 11% respectively developed diabetes mellitus several months after testing. The need for serial HbA1C determinations in cystic fibrosis is questioned.

Continuous monitoring of oesophageal pH is regarded as the gold standard for all reflux investigations. However, since gastro-oesophageal reflux is considered a normal phenomenon which occurs to a certain extent in each individual, the distinction between "normal" and "abnormal" is not always obvious and is not possible to achieve with a single test. Moreover, data depend on technical hardware such as recording devices and electrodes together with such patient characteristics as age, position, activity, and medication. Although much literature on pH monitoring has appeared recently, many investigations have failed to take into account the basic principles that are of major importance for any biomedical test such as reproducibility, sample reliability, and indications. There is a need to standardize the technique in order to compare studies performed in different centres, provided the technique is reproducible.

Although work in ROV (remotely operated vehicles) and AUV (autonomous underwater vehicles) has already led to the development of many vehicles, no surface robots have been designed. The Port of Bordeaux Authority in collaboration with the University of Bordeaux has undertaken the development of such an autonomous surface vehicle. The primary objective of this craft is to serve as a platform for hydrographic data acquisition. The ASV will moreover be an efficient tool destined to serve engineers and researchers involved in the study of sea. The ASV is a completely autonomous small surface craft. Its autonomy and reliability are guaranteed by its state of the art equipment. Navigation itself is monitored by a DGPS positioning system. The progress of the ASV is tracked by a mobile control station (MCS) which can either remain on-shore or be placed on-board a mother ship. The mobile control station is needed to define and preprogram the mission of the ASV before its departure, launch the ASV, monitor its progress (the MCS can retake control of the ASV at any moment) and recover it at the end of its mission. This paper describes the general architecture of the ASV and the technological choices made. It then focuses on the identification process and on the development of the control system. >

Recurrence plots, which were defined to appreciate the dynamics of a time series, were applied to the heart rates of subjects with a history of congestive heart failure and heart transplantation as they were administered normal saline. It is shown that constructing a recurrence plot is an efficient means of recovering dynamical information about heart beats. This method does not require as much data as traditional methods, and is computationally quick. Qualitative information about local divergence rates and relative dimensionality of the original signal are visually obvious. This information emphasizes that adiabatic systems may be usefully analyzed without requiring the reconstruction of an entire attractor. >

Despite therapy with diuretics, ACE inhibitors and digoxin morbidity and mortality in heart failure remain high and might respond favorably to an additional vasodilator.Male patients (n=450) with chronic heart failure (cardiac dysfunction and impaired exercise performance) on optimal current therapy (97% enalapril, 89% diuretics) were randomly assigned to double-blind treatment with felodipine extended release (5 mg BID) or placebo for 3 to 39 months (average, 18 months). Felodipine significantly reduced blood pressure and, at 3 months, increased ejection fraction (2.1% versus -0.1% units in the placebo group, P=.001) and reduced plasma atrial natriuretic peptide levels (-2.9 versus 26.9 pg/mL in the placebo group, P=.01) but did not improve exercise tolerance, quality of life, or the need for hospitalization. During long-term follow-up, the favorable effects on ejection fraction and atrial peptide did not persist, but felodipine prevented worsening exercise tolerance and quality of life. In the felodipine and placebo groups, mortality (13.8% versus 12.8%, respectively) and hospitalization (43% versus 42%) rates were similar, and a higher incidence of peripheral edema was the only apparent side effect of felodipine therapy.Felodipine exerts a well-tolerated additional sustained vasodilator effect in patients with heart failure treated with enalapril, but the only possible long-term benefit was a trend for better exercise tolerance and less depression of quality of life in the second year of treatment. The drug appears to be safe but not clearly efficacious in patients with heart failure.

Intestinal manifestations are the predominant symptoms of food allergy. Nevertheless, it is generally accepted that dietary proteins can also induce intestinal manifestations such as systemic reactions or symptoms related to the skin, the respiratory tract, the central nervous system, the urinary tract, the vascular system, the joints. The cause-effect relationships between the contact with the dietary protein (e.g. it is unclear if direct skin contact is more relevant in patients with cutaneous manifestations than ingestion) and the symptoms if often difficult to prove. As a consequence, the number of "extra-intestinal" manifestations that are suggested to be related to food proteins is probably greater than the number of manifestations that are generally accepted as such.

Recognition of the complex pathophysiology of heart failure and its high mortality has emphasized the need for prognostic markers that can be used in clinical assessment as well as in the design of mortality trials. Data from the Department of Veterans Affairs Cooperative Vasodilator-Heart Failure Trials (V-HeFT I, 642 patients; V-HeFT II, 804 patients) were therefore examined to determine the influence of prerandomization measurements on subsequent mortality.Patients entered into these trials were men with cardiac dysfunction and reduced peak exercise capacity. Measurements included in this analysis were left ventricular ejection fraction (EF) measured by radionuclide angiography, peak bicycle exercise oxygen consumption (VO2), cardiothoracic ratio (CTR) measured on a chest x-ray, ventricular arrhythmias assessed in a core laboratory by short-term Holter monitoring, plasma norepinephrine and plasma renin activity measured in a core laboratory only in V-HeFT II, and a variety of diagnostic and demographic data. The variables related only weakly to each other. EF, VO2, and CTR were powerful independent predictors of all-cause mortality in both studies. Ventricular arrhythmia was a significant independent predictor in V-HeFT II but not in V-HeFT I. Plasma norepinephrine but not plasma renin activity measured in V-HeFT II also had independent prognostic value. Other variables did not exert an independent effect on mortality.Optimal assessment of the mortality risk in an individual or a group of individuals with heart failure uses measurement of EF, peak VO2, CTR, plasma norepinephrine, and the presence of ventricular arrhythmias.

Adult patients with cystic fibrosis (CF) are at high risk for developing insulin-dependent diabetes mellitus. Therefore, the fast insulin release (FIR) to intravenously administered glucose was measured in 23 adult CF patients. The influence of the clinical parameters and type of gene deletion on the amplitude of the FIR, defined by the sum of the 1st- and 3rd-minute insulin concentrations was analyzed. In 11 of the 18 normoglycemic patients with exocrine pancreatic insufficiency and the 3 nontreated diabetic CF patients studied, an FIR value lower than the 3rd percentile was found. The female patients had higher mean FIR values than the male patients (62.8 +/- 39.6 vs. 27.9 +/- 17.9 mU/l; p0.05). No influence of age, body mass index, or pulmonary or liver involvement on the FIR was found. Subjects heterozygous for the delta F508 deletion had a similar insulin response as homozygous patients. The FIR level correlated negatively with the basal glucose level (r = 0.4; p0.001). In conclusion, 61% of the adult nondiabetic CF patients with exocrine pancreatic insufficiency presented a loss in acute insulin response, which could not be predicted by clinical or genetic parameters.

A case of type Ila glycogenosis presenting in early neonatal period is described. An unusual bradycardia and slow recovery from acute fetal distress were the leading signs. It is suggested to include metabolic myocardiopathies in the differential diagnosis of bradycardia in the newborn.

Eosinophilic gastroenteropathy in children is a rare, idiopathic disease characterized by eosinophilic infiltration of the gastrointestinal tract. We describe a 10-day-old boy with aspecific clinical manifestations (unconsolable crying). Treatment with a semi-elemental diet was successful, suggesting a "milk-sensitive enteropathy", although he had been exclusively breast fed. Recent literature is reviewed.

In two children with lymphocytic meningoradiculitis (Bannwarth's syndrome), IgG and IgM antibodies to Borrelia burgdorferi were demonstrated. Clinical and laboratory parameters of the syndrome are described and recent bacteriological and serological findings that link the syndrome to the American Lyme disease are discussed, as well as the effects of antibiotic treatment.

A variety of diploid human fibroblast lines have been successfully grown to high densities (greater than 10(6) cell/ml) on recently developed microcarriers. Interferon induction using poly I.poly C and a superinduction procedure resulted in yields greater than 10,000 units/ml with one cell line. A direct comparison of microcarrier cultures to roller bottle cultures showed equivalent interferon yields on a per cell basis and some apparent differences relating to optimum inducer concentrations and kinetics of interferon accumulation.

The need to produce antihydrogen as fuel for interstellar missions has been discussed by Forward and other. The use of lasers (10 6 J, 300 fs pulses) may result in 10 6 times higher conversion efficiencies than the use of accelerators for antiproton production. One problem is the radial ejection of the relativistically oscillating particles from the laser focus. A numerical calculation of the quiver drift has been performed and it was found that for the focus geometries of present day technologies, the interaction time is not too long for acheiving the necessary trident pair production in the laser focus.

1. Der Wert des Hochgebirgsklimas fUr die Behandlung der Lungentuberkulose ist hinreichend empirisch bekannt, wissenschaftlich aber noch nicht exakt bewiesen. Der Begriff „Reiz“-Klima ist erschUttert. 2. Der Behauptung mancher Kliniker, das Hochgebirge sei in Fallen von FrUhinfiltrat kontraindiziert, wird widersprochen und durch Darlegung einiger Falle aus der letzten Zeit die Ansicht erhartet, das die RUckbildung solcher Erkrankungen spontan und durch chirurgischen Eingriff auf 1700–1800 m HOhe mindestens ebensogut stattfindet wie in tieferen Regionen.

Two children, brother and sister, presenting a clinically peculiar form of mucopolysaccharidosis are reported. There exists a discrepancy between clinical and radiological data and biochemical findings. Enzyme study of the liver discloses a striking hyperactivity of the acid /J‐galactosidase. Hepatic ultrastructure differs from that of other previous descriptions of mucopolysaccharidoses, demonstrating a complex storage of lipids and mucopolysaccharides within swollen lysosomes. Copyright © 1969, Wiley Blackwell. All rights reserved

A description is given of a boy who presented early and severe clinical and radiological signs of chondrodystrophy without increased mucopolysacchariduria. Liver acid β-galactosidase activity was decreased. Ultrastructural studies disclosed the presence of clear membrane-bound inclusions, particularly numerous in fibrocytes and glomerular epithelial cells. In hepatocytes and neurons only a few pleiomorphic inclusions were present. In skin tissue culture, living cells were filled with dark granules showing an aspect characteristic of the “I-cell” phenotype. Findings that distinguish this clinical pattern from the typical mucopolysaccharidoses are discussed.

The glucose kinetics are modified in obese children. This fact does not appear after an intravenous load of glucose, but it may be disclosed when the penetration of glucose into the cells is forced either by the oral administration of a large amount of glucose or by the neous intravenous injection of glucose and of a supramaximal dose of insulin. The insulin response of the pancreas to oral glucose and intravenous tolbutamide is not significantly increased in obese children. The rise of the fasting level of free fattyacids is significant, but the response of adipose tissue to glucose is comparable to that observed in normal children.

The fact that hemolytic streptococcal infections are implicated in the causation of rheumatic fever is well documented (1-3). Further, there is much evidence to suggest that rheumatic fever occurs as a result of an inappropriate immune response on the part of the host to the streptococcus or its products (4,5). Nevertheless, the pathogenesis of rheumatic fever remains obscure, its elucidation being seriously handicapped by the lack of a suitable experimental analog. The development, therefore, of an affection in experimental animals, bearing sufficient resemblance to rheumatic fever in man to satisfy the most stringent criteria, might well constitute a significant advance toward definition of the mechanism by which the human disease arises. One avenue of attack on this problem is represented by the attempt to simulate in experimental animals a sequence of events comprable to that which is assigned importance in human rheumatic fever; namely, repeated infections of the upper respiratory tract with group A ...

Intravenous glucose tolerance tests were performed on a large number of children ranging in age from 4 days to 15 years. The rate of glucose assimilation (K) was calculated as the slope of the semilogarithmic straight line of glucose disappearance. Using this test, glucose tolerance during the various stages of growth has been estimated.

Biochemical studies were performed on brain biopsies, and ultrastructural studies on brain and liver biopsies from three children presenting clinically the infantile form of Tay-Sachs disease. Gangliosides were markedly increased both in grey and white matter, and consisted mainly of fraction GM2. In one case (patient 1), the amount of N-acetylaminotrihexosyl-ceramide, the asialo-residue of ganglioside GM2, was much larger than in the two other cases (patients 2 and 3). Enzyme studies performed on liver tissue disclosed, in patient 1, a nearly complete absence of the total hexosaminidase activity, which was within normal limits in the two other cases. Ultrastructural data in brain and liver were also different in the three cases. In patient 1, the lipid inclusions of the neurons, astrocytes and endothelial cells were markedly more pleiomorphic than in cases 2 and 3. In the liver of patient 1, hepatocytes and, in a lesser degree, Kupffer cells were full of lipid inclusions, whereas in the two other cases, only a small number of lipid lamellar elements were present in a few cells.

The measurement of HbA1 gives an "objective" estimate of the degree of metabolic control of diabetes during the erythrocyte lifespan. 333 assays in 85 young diabetics aged three to twenty-three years showed a mean HbA1 of 10.9 +/- 2.6% (controls: 7.4 +/- 1.4%). HbA1 levels parallel the clinical evaluation of the degree of control. HbA1 concentrations are correlated with the duration of diabetes (r = 0.26; p less than 0.001), triglyceridemia (r = 0.22; p less than 0.001), cholesterolemia (r = 0.26; p less than 0.001) and glycemia (r = 0.50; p less than 0.001). The HbA1 glycemia correlation grows stronger as glycemia increases. This probably reflects the existence of a labile form of HbA1. HbA1 concentrations measured repeatedly over one year were not significantly different in diabetics with and without retinopathy, probably because the study period was too short. Measurement of HbA1 is also of value in diagnosing non-compliance.

Diabetic children should consume the number of calories normal for their age, with an ideal % nutrient distribution: +/- 55% carbohydrate (especially delayed-resorption carbohydrates), +/- 30% lipid and +/- 15% protein. In some countries e.g. Belgium, the excessive proportion of fat in the diet must be reduced. Calorie requirements may vary a lot from one day to the next, but nutrient fluctuations do not entail proportional changes in metabolic control, as long as insulin adaptation is adequate. It is essential that diabetic children adapt their food intake to their appetite; they do not have set needs, since they are growing and their physical activity varies. Imposing a weighed and measured diet is neither desirable for diabetic control nor for the psychological factor. A diet which reduces only carbohydrates automatically favours an excessive supply of lipids which is bad for the blood vessels. A general calorie restriction prevents normal growth and this, in extreme cases, can lead to Mauriac's syndrome. At the other extreme, a disordered diet causes large glycaemic fluctuations with hypoglycaemic accidents and hyperglycaemic spurts responsible for degenerative complications. Dietary democracy, rather than anarchy or authoritarianism, leads to better control of diabetics. The diet must be well-balanced and individually adapted, bearing in mind insulin, physical activity, etc. Where two daily insulin injections are given, what is most important is the distribution of glucides over the various meals. The use of pen-injector provides for greater freedom in the diet. It must be borne in mind that the hyperglycaemic effect of sucrose is restrained if the sucrose is mixed with proteins and lipids during a meal; some sweets may be allowed even in the absence of intense physical activity or hypoglycaemia. The use of synthetic sweeteners and "diabetic" diet products, often useless and expensive, is not recommended.

Massive endobronchial bleeding during cardiopulmonary bypass was encountered in one patient following pulmonary embolectomy and in another following an elective aorta-coronary bypass procedure. Successful management of this complication necessitates control of ventilation by prolonging cardiopulmonary bypass to ensure adequate oxygenation, suctioning the airway to clear blood from the major tracheobronchial tree, and immediately instituting 20 cm H2O of positive end-expiratory pressure (PEEP) to control endobronchial bleeding.