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This paper discusses the approach adopted by the authors for teaching an undergraduate course (lecture and laboratory) in digital controls. Theoretical material is developed in the lecture concerning the application of direct digital control (DDC) to an analog bench-scale system consisting of a DC motor and tachometer. A simulation of the closed-loop control system with embedded digital controller is developed and run by the students using the TUTSIM dynamic simulation language. Finally, students perform a laboratory experiment in which they write a program to control the actual system using a personal computer and inexpensive interface card. The combination of hands-on experience and computer simulation with the more traditional, theoretical lecture material provides a well-rounded learning experience that better prepares the students to implement digital control systems in the real world. >

Construction of DNA fragment libraries for next-generation sequencing can prove challenging, especially for samples with low DNA yield. Protocols devised to circumvent the problems associated with low starting quantities of DNA can result in amplification biases that skew the distribution of genomes in metagenomic data. Moreover, sample throughput can be slow, as current library construction techniques are time-consuming. This study evaluated Nextera, a new transposon-based method that is designed for quick production of DNA fragment libraries from a small quantity of DNA. The sequence read distribution across nine phage genomes in a mock viral assemblage met predictions for six of the least-abundant phages; however, the rank order of the most abundant phages differed slightly from predictions. De novo genome assemblies from Nextera libraries provided long contigs spanning over half of the phage genome; in four cases where full-length genome sequences were available for comparison, consensus sequences were found to match over 99% of the genome with near-perfect identity. Analysis of areas of low and high sequence coverage within phage genomes indicated that GC content may influence coverage of sequences from Nextera libraries. Comparisons of phage genomes prepared using both Nextera and a standard 454 FLX Titanium library preparation protocol suggested that the coverage biases according to GC content observed within the Nextera libraries were largely attributable to bias in the Nextera protocol rather than to the 454 sequencing technology. Nevertheless, given suitable sequence coverage, the Nextera protocol produced high-quality data for genomic studies. For metagenomics analyses, effects of GC amplification bias would need to be considered; however, the library preparation standardization that Nextera provides should benefit comparative metagenomic analyses.

Viral and bacterial pathogens are a significant economic concern to the US broiler industry and the ecological epicenter for poultry pathogens is the mixture of bedding material, chicken excrement and feathers that comprises the litter of a poultry house. This study used high-throughput sequencing to assess the richness and diversity of poultry litter bacterial communities, and to look for connections between these communities and the environmental characteristics of a poultry house including its history of gangrenous dermatitis (GD). Cluster analysis of 16S rRNA gene sequences revealed differences in the distribution of bacterial phylotypes between Wet and Dry litter samples and between houses. Wet litter contained greater diversity with 90% of total bacterial abundance occurring within the top 214 OTU clusters. In contrast, only 50 clusters accounted for 90% of Dry litter bacterial abundance. The sixth largest OTU cluster across all samples classified as an Arcobacter sp., an emerging human pathogen, occurring in only the Wet litter samples of a house with a modern evaporative cooling system. Ironically, the primary pathogenic clostridial and staphylococcal species associated with GD were not found in any house; however, there were thirteen 16S rRNA gene phylotypes of mostly Gram-positive phyla that were unique to GD-affected houses and primarily occurred in Wet litter samples. Overall, the poultry house environment appeared to substantially impact the composition of litter bacterial communities and may play a key role in the emergence of food-borne pathogens.

In refluxing diglyme, the title α-hydroxy imines 7 and 8 rearrange cleanly to amino ketones 9 and 10 substituted on the carbon α to nitrogen by an allyl or a propargyl group. In the case of α-hydroxy imine 9 , the migration of the allyl group occurs with an allylic transposition.

Desulfovibrio are sulfate-reducing anaerobic gram-negative rods that have been proposed as potential periodontopathogens. We investigated the capacity of Desulfovibrio to invade epithelial cells and induce cytokine secretion from these cells. Desulfovibrio strains were co-cultured with KB cells and counts of intracellular bacteria evaluated up to 3 days after infection. Desulfovibrio desulfuricans and Desulfovibrio fairfieldensis were able to survive within epithelial cells. Intracytoplasmic location of both bacterial species was confirmed by confocal laser scanning microscopy and transmission electron microscopy. Invasion was sensitive to nocodazole, an inhibitor of microtubule polymerization, but not to cytochalasin D, a microfilament inhibitor, suggesting that microtubule rearrangements were involved in the internalization of Desulfovibrio strains by KB cells. Infection by Desulfovibrio resulted in increased production of IL-6 and IL-8 by KB cells. The ability of D. desulfuricans and D. fairfieldensis to survive within oral epithelial cells and to modulate the epithelial immune response may contribute to the initiation and progression of periodontal diseases.

Plant peptides of a rapeseed peptone were labelled with a coumarin fluorescent probe. The free-probe does not incorporate cell cytoplasm and is not cytotoxic at a concentration below 10 μM. Observations by Confocal Microscopy of CHO cells incubated in presence of labelled peptides indicate no fixation of the peptides on cell membrane receptors, but their incorporation inside cell cytoplasm. This integration seems to be time-dependant while the fluorescence intensity reaches saturation after more than 12 hours of incubation.

The present study deals with the fracture behaviour of anthracite-based carbon materials. As their behaviour is nonlinear and nonelastic, crack growth resistance curves (R-curves) are determined, and loading-unloading procedure in three-point bending on single-edge notch beams is used. To determine the correct specimen size, a preliminary study of the size effect is performed. The R-curves exhibit a typical shape showing three stages: an increase in growth energy due to process zone development; a plateau value corresponding to steady-state crack propagation, which is used in this study to characterize the behaviour; and a sharp increase of energy due to specimen edge effects. The influence of the microstructure, especially the particle type and orientation, is investigated. Microstructure with higher anthracite fraction leads to easier crack growth. The micromechanisms governing the crack growth conditions are described and discussed.

In refluxing diglyme, the title α-hydroxy imines 7 and 8 rearrange cleanly to amino ketones 9 and 10 substituted on the carbon α to nitrogen by an allyl or a propargyl group. In the case of α-hydroxy imine 9 , the migration of the allyl group occurs with an allylic transposition.

On 11 June 1996, three suspected cases of legionnaires’ disease in a group of 42 Dutch tourists were reported to the local public health authority by Millau hospital in south west France. The group (group 1) had been touring with caravans and staying at d

This paper explores the hypothesis that the depth cues and display quality of a 3D volumetric display provides advantages for learning simple tasks. Experimental data generated by human subjects using the Perspecta 3D Volumetric Display are compared to like data generated using a 2D flat screen liquid crystal display (LCD). These data show that the Perspecta display provides advantages over the LCD display with respect to peak performance of simple tasks.

International audience; Chondrocytes use mechanical signals, via interactions with their environment, to synthesize an extracellular matrix capable to withstanding high loads. Most chondrocyte-matrix interactions are mediated via transmembrane receptors such as integrins or non-integrins receptors (i.e. annexin V and CD44). The aim of this study was to analyze, by flow cytometry, the adhesion molecules (alpha5/beta1 integrins and CD44) on rat chondrocytes seeded into 3D biosystem made of alginate and hyaluronate. These biosystems were submitted to mechanical stress by knocking the biosystems between them for 48 hours. The expression of type I and type II collagen was also evaluated. The results of the current study showed that mechanical stress induced an increase of type II collagen production and weak variations of alpha5/beta1 receptors expression no matter what biosystems. Moreover, our results indicated that hyaluronan receptor CD44 expression depends on extracellular matrix modifications. Thus, these receptors were activated by signals resulted from cell environment variations (HA addition and modifications owing to mechanical stress). It suggested that this kind of receptor play a crucial role in extracellular matrix homeostasis. Finally, on day 24, no dedifferentiation of chondrocytes was noted either in biosystems or under mechanical stress. For all biosystems, the neosynthesized matrix contained an important level of collagen, which was type II, whatever biosystems. In conclusion, it appeared that the cells, under mechanical stress, maintained their phenotype. In addition, it seems that, on rat chondrocytes, alpha5/beta1 integrins did not act as the main mechanoreceptor (as described for human chondrocytes). In return, hyaluronan receptor CD44 seems to be in relation with matrix composition.

Mechanical forces regulate the morphology and the metabolism of endothelial cells through mechano-sensitive structures existed on cell surface. In this work, the influence of a steady laminar or disturbed flow on cell cytoskeleton and its connection with differential adhesion molecules expression at the apical side of the endothelial cell were studied in vitro. A 3D cell scanner coupled with a fluorescence microscope allowed the authors to visualize the spatial organization or distribution of cytoskeleton and adhesion molecules marked by specific fluorescent probes. In static conditions, the actin fibers presented a random structure, but after exposure to shear stresses, it was observed a reorganization of these fibers. The distribution of adhesion molecules at the cell surface seems to be linked to these structural modifications. These studies help one to better understand the response of endothelium to complex flows near vascular singularities.

Existing methodologies for determining delay fault coverages or for building up a delay fault dictionary are sometimes accurate, but rarely fast and easy to implement. Therefore, with the aim of removing these deficiencies, a new and more efficient fault simulation strategy for gate delay faults in combinational or scan-based circuits is presented. This method is based on a critical path tracing algorithm, thus avoiding the explicit simulation of each delay fault in the circuit. The novelty of the solution proposed to compute the detection threshold of a detectable delay fault increases the interest of the method, although it is computed approximately. Simulation results obtained for the ISCAS85 combinational benchmark circuits show the efficiency of the proposed method. >

Delay fault testing has been an active research topic in the last ten years. Recently proposed methods try to move the sampling time of the circuit outputs during testing to produce better fault coverages than that obtained by using a fixed observation time method. In the same way, the authors propose to use such a testing scheme to improve delay fault diagnosis when compared to methods based on fixed output sampling times. The timing analysis which gives the output observation times applied during the test is first described in this paper. Next, the authors present the diagnosis method they implemented with the new testing scheme. Finally, results showing the effectiveness of a variable sampling time strategy for delay fault diagnosis are given. >

The assembly of structures, such as the International Space Station, in orbit requires precise alignment of telerobotically manipulated component modules. The alignment process is often made more difficult by inability to simultaneously observe and control the components to be positioned. Video observation of the process from a fixed vantage point is a less than optimal solution. A real-time, operator-in-the-loop virtual environment simulation was proposed which would allow the operator to observe the position of a simulated manipulator arm and payload from any vantage point. When the user views the simulation through a position-tracked, head-mounted display, he or she is "immersed" in the virtual world. The simulation, which involved the networking of four different computer systems and associated peripheral hardware including specialized robot arm controllers, was integrated and demonstrated. Possible further directions and human factors investigations are discussed.

Polymorphonuclear neutrophil (PMN) adherence receptors expression varies with leukocyte activation state. Their quantification need accurate and inter-laboratories reproducible methods, without artefactual activation.The aim of this study was to study the influence of cell preparation on PMN adherence receptors expression.It was proposed to quantify, using immunolabeling standard (QIFIKIT(R), Dako), surface expression of the main adherence receptors (L-selectin and B(2) integrins), from different preparations of PMN: total blood collected with EDTA, isolated PMN by density gradient Polymorphprep(TM) 1,113 (Nycomed Pharma) and formaldehyde fixed PMN.A decrease of all receptors was noted after isolation and fixation of PMN, in comparison with whole blood PMN analysis. These results differed from data previously reported since, in these studies, activated phenotypes (increased of B(2) integrins) were observed after isolation and fixation methods.The present study provides strong evidence that pre-analytical conditions are sources of biological variations and thus extreme care must be taken in the interpretation of results. It underlines the interest of consensual practices for these pre-analytic and analytic parameters in order to compare results in multicenter and longitudinal studies.

Evaluation of alternate strategies for municipal solid waste (MSW) management requires models to calculate environmental emissions as a function of both waste quantity and composition. A methodology to calculate waste component-specific emissions associated with MSW combustion is presented here. The methodology considers emissions at a combustion facility as well as those avoided at an electrical energy facility because of energy recovered from waste combustion. Emission factors, in units of kg pollutant per metric ton MSW entering the combustion facility, are calculated for CO2-biomass, CO2-fossil, SOx, HCl, NOx, dioxins/furans, PM, CO, and 11 metals. Water emissions associated with electrical energy offsets are also considered. Reductions in environmental emissions for a 500-metric-ton-per-day combustion facility that recovers energy are calculated.

Adherence receptors are essential for heterotypic (endothelial cell, platelet) polymorphonuclear neutrophil (PMN) interaction. Determination of their expression level give information about activation state and functionality of PMN. Use of flow cytometry associated with an immunolabeling standard, represented by beads coated by a determined amount of immunoglobulins (Qifikit, Dako), allows analysis of specific antibody binding capacity and gives information about antigen density. Using this methodology, the exploration of surface adherence receptors, L-selectin (CD62L) and b2-integrins (CD11a-c/CD18) from PMN unstimulated and incubated with pro-inflammatory stimuli, formyl-methionyl-leucyl-phenylalanine (fMLP) and tumor necrosis factor a (TNFa), allows, on the one hand, the establishment of basal expression values on resting PNN and on the other hand, the study of PNN reactivity. This method of quantification can be applied to clinical studies as adherence receptor deficiency syndromes or inflammatory, infectious and vascular diseases.

In this study, we measured the influence of cholesterol rigidification on oxygen permeability in human endothelial cell monolayer membranes (ECs). Cholesterol-induced membrane rigidification was assessed at different membrane depths by a fluorescence polarization method with diphenyl-hexatriene (DPH) and 1-(4-trimethylamino)-6-phenylhexatriene (TMA-DPH). Fluorescence quenching by oxygen was probed in preferentially labelled membrane with pyrene butyric acid (PyC4) and pyrene dodecanoic acid (PyC12), as shown with a 3D fluorescence microscope (CellScan System). With both probes the experiments revealed a decrease in oxygen diffusion as the cholesterol concentration increased in the medium culture (from 3.42 microM to 17.11 microM). We showed that very low concentrations of cholesterol (about 1000 times below normal value, 6.2 mM) particularly decrease oxygen levels or diffusion rate in the middle region of the membrane. In conclusion, these findings prove in a direct manner that cholesterol significantly affect the endothelial barrier function and molecular oxygen transfer to underlying tissues. Risk factors (cholesterol) directly would contribute to tissue ischemia.

Study of the osmotic resistance to hypotonic medium of platelets has often been suggested as a global test to assess the viability of these cells in transfusion or to study modification during haematological pathologies. A number of authors have analysed the behaviour of platelets in hypotonic media by a variety of methods (cell count, determinations of substances released, morphology, etc.), but most studies are currently based on the so-called "Hypotonic Shock Response" test (HSR). In this study, the authors describe a new automated and reproducible apparatus, called fragilimeter, using slow dialysis to assess platelet osmotic resistance. The variations in light transmission through a platelet suspension according to ionic strength are linked to the change in cellular volume and lysis and characterise the osmotic behaviour of the cells. The results revealed the good reproducibility and sensibility of the technique. This apparatus allows also the realisation of the "HSR" test.

Herpes simplex virus type-1 (HSV) amplicon vectors containing neuroprotective genes can alter cell physiology and enhance survival following various insults. However, to date, little is known about effects of viral infection itself (independent of the gene delivered) on neuronal physiology. Electrically-evoked synaptic responses are routinely recorded to measure functional alterations in the nervous system and were used here to assess the potential capability of HSV vectors to disrupt physiology of the hippocampus (a forebrain structure involved in learning that is highly susceptible to necrotic insult, making it a frequent target in gene therapy research). Population excitatory post-synaptic potentials (EPSPs) were recorded in the dentate gyrus (DG) and in area CA3 in vivo 72 h after infusion of an HSV vector expressing a reporter gene (lacZ) or vehicle into the DG. Evoked perforant path (PP-DG) or mossy fiber (MF-CA3) EPSPs slope values measured across input/output (I/O) curves were not altered by infection. Paired-pulse facilitation at either recording site was also unaffected. X-gal-positive granule cells surrounded the recording electrode (PP-DG recording) and stimulating electrode tracts (MF-CA3 recording) in animals that received vector, suggesting that we had measured function, at least in part, in infected neurons. Because of the negative electrophysiological result, we sought to deliver a gene with an HSV amplicon which would affect the measured endpoints, as a positive control. Delivery of calbindin D28kpotentiated PP-DG synaptic strength, indicating that our recording system could detect alterations due to vector expression. Thus, the data indicate that HSV vectors are benign, in regard to effects on synaptic function, and support the use of these vectors as a safe method to deliver selected genes to the central nervous system.

The pathogenesis of atheromatous and/or thrombotic vascular diseases involves rheological parameters, soluble mediators and cellular agents. The many studies that have tried to establish correlations between plasma factors, shear stress and the risk of ischemia have left some questions unanswered. Current exploration methods are now focusing on the determining role of cells. Activated cells express adhesion molecules on their membranes, which allow to communicate in a homo- or heterotypical manner. Quantifying adherence molecules on the surface of platelets, leukocytes and endothelial cells provides an assessment of the "adhesive phenotypical profile". Quantitative cytometry, using beads coated with a known amount of immunoglobulins as calibrators, is perfectly suited, through its multiple parameter analyses and the specificity provided by monoclonal antibodies, for the quantification of membrane antigens. Measuring the adhesive profile on the surface of cells that are implicated in vascular disease makes it possible to correlate that phenotype to the ischemic risk in such diversified pathologies or circumstances as intermittent angor, myocardial infarction, angioplasty, insulin-dependent diabetes or pre-eclampsia. In addition, that quantification permits monitoring the action of new therapeutical agents targeting adherence molecules.

A prototype liquid scintillator-filled halar fibre is described and the results of some preliminary tests designed to demonstrate the feasibility of its use in calorimeter readout are given.

Epidural catheters placed for analgesia during labor and delivery can be reused in the postpartum period for postpartum tubal ligation anesthesia. This study examined the success rate of such reactivation of epidural catheters.We studied all patients who had received an epidural anesthetic for labor and delivery and who had the epidural catheter reactivated at a later time to provide anesthesia for a postpartum tubal ligation (PPTL) procedure between January, 1993 and June, 1995. The patients were divided into four groups based on the interval between delivery and PPTL incision: (a) less than 8 hours, (b) 8 hours to less than 16 hours, (c) 16 hours to less than 24 hours and (d) 24 hours or more.Overall, 92% (129/140) of the patients had their epidural catheters successfully reactivated. The success rate in all but the last group was over 90%, while only 80% of catheters could be reactivated if left in place for more than 24 hours.Epidural catheters can be reactivated reliably for as long as 24 hours after they are placed.

Denise Dumas, a nurse at the Hôtel-Dieu du Sacré-Coeur de Jésus hospital, in Quebec City, and Louise Pelletier, an associate professor at the Ecole des sciences infirmières of Université Laval, are interested in promoting understanding of problems linked to hyperactivity in school-age children. They suggest appropriate nursing interventions for child psychiatry units in hospitals and outpatient clinics. The authors give a definition of attention-deficit hyperactivity disorder, specifying its prevalence, etiology and treatment, and describe the behaviour of the hyperactive child. They go on to look at the concept of self-perception and deal with its development and its importance in children's lives. Most importantly, the authors suggest nursing interventions suited to the needs of hyperactive children.

We present the new digital solar radio spectrograph located at the Thermopyles station, Greece, operated by the University of Athens. Observations cover the range from 110 to 600 MHz, using a 7-m parabolic antenna. The reception system uses two techniques in parallel: sweep frequency and multi-channel, the latter being based on the Acousto-Optical technique. The data acquisition system is based on two subsystems, a Sun Spare-5 workstation and a front end based on a VME Motorola system. The two subsystems are connected through the Ethernet and are operated using the VxWorks real-time package. The daily operation is completely automated: pointing of the antenna to the sun, starting and stopping the observations at pre-set times, acquiring data, compressing data by silence suppression in real time, and archiving the data on a routine manner on DAT tapes. Apart from its usual function, this instrument will be used in conjunction with other instruments, including the Nançay decameter array and the low frequency radio receivers on the Wind spacecraft.

The effect of cholesterol hemisuccinate incorporation on the rheological properties of the erythrocyte membrane was assessed by measuring deformability (elongation index) and osmotic fragility ("baseline hemolysis"). These two experimental methods have different response sensitivities according to the incubation protocols (12 h 25 degrees C/12 h 25 degrees C then 12 h 37 degrees C) ant to the amount of cholesterol incorporated in the membrane (C/Pt from 0.18 to 0.83). The deformability and osmotic fragility variations observed are inversely related with the cholesterol concentrations incorporated. The experimental differences observed in the deformability and osmotic fragility are discussed in view of the type of membrane deformation and of the signals collected by the two systems.

The authors describe a previously unreported complication of insertion of an automatic implantable cardioverter-defibrillator via the left subcostal surgical approach. Splenic hematoma, intraperitoneal hemorrhage and hypotension developed in a 66-year-old man within 5 days of implantation, and the patient underwent splenectomy.

Chondromyxoid fibroma is an uncommon bone tumour, found predominantly in the metaphyses of the long bones of the lower limbs. The authors describe a patient in whom the tumour arose from the occipital bone. To the authors' knowledge, this is only the second report of chondromyxoid fibroma occurring in this location.

It is speculated that nicotine receptor ligands might be of therapeutic benefit for the treatment of obesity, anxiety, and memory loss. With the exception of nicotine, few selective high-affinity agents exist. (-)Epibatidine (1), isolated from Ecuadoran frogs, shows structural resemblence to (-)nicotine (2). Molecular modeling studies reveal that the N to N distance in 1 (5.5 A) is greater than that found in 2 (4.9 A). This distance exceeds that previously considered optimal for the nicotine receptor pharmacophore (4.8. ± 0.3 A) by about half a bond length. Nevertheless 1 binds (Ki = 0.055 nM) at [3H]nicotine-labeled receptors with higher affinity than 2 (Ki = 1.5 nM). Although our studies are still in progress, molecular superimposition and preliminary results with various structurally modified analogs suggest that it is the conformationally constrained nature of 1 that accounts for its high affinity. For example, 6-chloronicotine binds only with slightly higher affinity (Ki = 0.6 nM) than nicotine suggesting, at least for nicotine, that the chloro substituent is tolerated but does not contribute significantly to binding. Excision of the ethano bridge of deschloroepibatidine, to yield isonornicotine (Ki = 12.5 nM), results in reduced affinity. Isonicotine binds with similar (Ki = 7.3 nM) affinity. The bridged azabicycloheptane system likely fixes the structure of epibatidine in a highly receptor-preferred conformation. The pharmacophore for nicotine receptor binding will require reconsideration and should take into account the longer N-N distance of epibatidine. The N-N distance in epibatidine may be optimal, whereas that in isonornicotine is longer, and that for nicotine shorter. (Supported in part by funding from TDC/CIT.)

We present the real-time digital data processing system named 'ARTEMIS' that was developed and constructed by the Space Research Department (DESPA) of Paris-Meudon Observatory to digitize, calibrate, format, date, process, compress, and archive in real time signals from multichannel receivers. This system is controlled by a multiprocessor computer based on Motorola MC 68010/68020 processors; it permits the automatic, routine recording of 128 parallel channels at a rate up to 300 samples per second and per channel with a 12-bit accuracy (4096 levels of intensity); it is used to process and record the 120 channels of a multichannel solar radiospectrograph in the frequency range 110-469 MHz; the remaining 8 channels are used for a scanning spectrograph in the frequency range 30-80 MHz and a two-dimensional multicorrelator interferometer at 75.5 MHz. The large quantity of raw data is reduced in real-time from about 1.3 Gbytes to about 40 Mbytes per day by the use of an original algorithm for real-time data compression. It is expected that this new facility will allow us to build a very large data base of digitized and accurately calibrated solar events, in order to achieve statistical measurements over long periods of time. © 1993 Kluwer Academic Publishers.

To harness the energy contained in such unconventional sources as winds, tides, and sunlight, a power system must incorporate an energy storage device to act as a buffer between the source and the load. Since the size of the energy storage device depends upon the relative timing of the availability of energy and the load demand, a system simulation is a logical approach to the study and design of power systems using these unconventional en ergy sources. GPSS is presented as an excellent simula tion vehicle. The physical properties to be simulated are discussed and the resulting GPSS programs are presented. Some proposed applications for these power systems are presented.

Two patients under cytotoxic therapy developed pigmentation of their fingernails. The first, under doxorubicin and cyclophosphamide for lymphoma, had horizontal streaks, while the second, under cyclophosphamide for periarteritis nodosa, exhibited diffuse pigmentation. Nail pigmentation, which occurs after an interval of some weeks or months, varies from diffuse to horizontal or longitudinal streaks. Reversal of nail pigmentation some months after withdrawal of the drug is usual. Skin or mucous membrane pigmentation may coexist. The mechanism of pigmentation remains obscure. These changes are observed more frequently in black than in white patients. In some instances, they have been recorded in several members of the same family.

Qualification test results of pigtailed PirPN APD'sD.Dumas - M.Marchand - C.Ruineau - J.QuevrinCIT - ALCATEL - Departement TransmissionCentre de Villarceaux - B.P.6 - 91620 - LA Ville du Bois - FranceAbstractSilicon PirPN avalanche photodiodes with fiber pigtails (type CG 5705 FB2) have been submitted to qualifi-cation testing in order to evaluate simultaneously the performance of the crystal and the optical output fiberunder extreme environmental and operational conditions.Electrical and optical results obtained demonstrate excellent performance of the photodetectors during thequalification testing and prove their suitability for telecommunication equipment.I. IntroductionSilicon PirPN avalanche photodiodes with fiber pigtails (type CG 5705 FB2) have been submitted to quali-fication testing in order to supply optoelectronic devices for the fiber optic netwoork in Biarritz.The investigation was carried out in cooperation with SAT and LTT.Qualification testing on 36 devices was divided into 5 groups

Dumas D. L'urbanisation touristique du littoral de la Costa-Blanca (Espagne). In: Cahiers du Centre nantais de recherche pour l'aménagement régional, n°13, 1977. Actes du colloque sur L'aménagement du littoral, Nantes, décembre 1976. pp. 43-50.

An adenopathy perforated into the esophagus in a thirty-two-year old woman from black Africa with mediastinal and abdominal tuberculous adenopathies. The fistula was disclosed upon endoscopic examination in the absence of esophageal symptoms. The characteristics of such fistulas are recalled: location in the middle third of the esophagus, inconspicuousness of symptoms, scarcity of complications among which digestive hemorrhage is the most significant, usually favorable course under medical management alone. The latency of fistulas between tuberculous adenopathies and the esophagus warrants routine fiberoptic endoscopy in patients with mediastinal tuberculous adenopathies.