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Charging for freshwater use raises debate on water suppliers' financial sustainability and, social and operational sector efficiency problems. The issue stands out when suppliers' income flows are insufficient to cover production costs or household revenues are low, making it difficult for tariffs to increase. Moreover, it is even worse with the combination of these factors in watersheds with water scarcity. The present work analyzes the freshwater use charging from the perspective of cost increment destination in the sanitation sector. We compared a scenario of cost absorption with the possibility of transfer to final consumers in the first block tariff, fixed by volume ( #2a), and the second block tariff charged by additional m3 consumed (#2b). Results show that scenario #1 reduces resource availability for investments, compromising infrastructure maintenance and service expansion. Alternatively, as a natural monopoly sector, the pass-through to consumers is the most likely. Both #2a and #2b scenarios nullify the encouragement of rational use and operational efficiency, add risk to environmental sustainability, and compromise basin committee plans. However, in the #2b scenario, the possibility of minor water consumption by households, changing for the first block tariff, brings back the #1 scenario possibilities. Scenario #2a, as a plausible choice, demands an accurate discussion of governance in freshwater charging.

The dynamic retention of deuterium in a full-tungsten JET-like tokamak is investigated thanks to the Dynamics of Wall Elements (DWE) code. DWE is a wall model coupled to the SolEdge-EIRENE edge-plasma transport code. It is composed of two internal codes: (i) WE-temp, which determines the wall temperature, and (ii) MHIMS, which determines the transport, trapping and desorption of hydrogen isotopes in the wall material. In this work, four consecutive discharges are modeled and analysed with DWE. These discharges are identical and present a transition from a H-mode phase to a L-mode phase, which induces strongly different plasma-wall interactions. The main results are as follows. (i) A release of deuterium is observed at the vicinity of both strike-points at the end of the H-mode phase. This dynamics is explained by an increase of the wall temperature at both strike-points due to the strong plasma heat flux received there, leading to detrapping from trap with low detrapping energy. On the contrary, during the subsequent L-mode phase, the wall temperature at the strike-points decreases, leading to retention by filling the trap emptied during the H-mode. (ii) A release of deuterium from the first-wall is unexpectedly observed at the transition between the H-mode and the L-mode. This release is a consequence of a decrease in implantation energy between the two phases, as it entails a shallower implantation of deuterium. Despite the different material considered in the simulation, the latter result offers a possible explanation of the strong transient release of deuterium experimentally observed in the JET-ILW at the NBI cutoff during high density H-mode discharges.

International audience; Hydrogen isotopes transport in tokamaks is a crucial issue for several reasons, especially in the divertor exposed to the highest heat and particles fluxes. First, the total inventory of radioactive material trapped in the reactor must be limited to a certain amount (in ITER, the limit of tritium in the vacuum vessel is 1 kg). Secondly, outgassing of hydrogen from the monoblocks composing the divertor and from the tokamak first wall can reduce the plasma performances. Finally, the lifespan of plasma facing components can be reduced due to hydrogen-induceddamage.A new method coupling 2D Finite Element monoblock simulations of H transport [3] to plasma codes such as SOLPS [4] is presented. This work investigates the influence of the divertor neutral pressure on the full divertor hydrogenic inventory. It is shown that the peak heat flux (and therefore the peak temperature) decreases with the neutral pressure. The H inventory is maximum in the strike points neighbourhood and a local minimum is observed at the strike points. Even considering very conservative assumptions (eg. s of continuous exposure), the total divertor inventory of hydrogen isotopes is around 14 g which is much lower than the ITER safety limit. Moreover, this divertor inventory only varies slightly with the divertor neutral pressure (from 12 g to 14 g)

International audience; Understanding hydrogen isotopes transport in plasma facing components is crucial for tokamak operation and for safety issues. Numerical modelling is often required and can be complex when applied to multi-material environments with complex interfaces and geometries (2D/3D). This is the case for many plasma facing components such as the monoblocks that will be used in the divertor of present and future fusion reactors like WEST and ITER. To this day, few studies have simulated hydrogen transport and retention in these components with relevant physics and geometries. To simulate these processes, a finite element modelling code called FESTIM has been developed [1]. FESTIM can perform complex multidimensional simulations with several materials. The code also simulates heat transfer in solids to take into account the non-homogeneous temperature field induced by the non-homogeneous heat flux and by the cooling system. FESTIM has been used to estimate the hydrogen inventory in the ITER divertor with different exposure conditions such as surface temperature and surface hydrogen concentration using machine learning algorithm. The aim of this study is to apply the same methodology to the WEST tokamak using SOLEDGE3X-EIRENE plasma backgrounds in various divertor operational regimes (density scan, power scan). In addition, several ITER operation cases are examined.

International audience

In all plasma devices, a constant exchange of particle develops between the plasma and the wall. This phenomenon, referred to as recycling, is of critical interest for those reactors as, once the plasma is established, particle recycling represents the main particle source for the plasma. A complete understanding of the recycling phenomenon is therefore essential to ensure a reliable plasma density control and optimum performance. However, the in-situ experimental study of recycling remains challenging. Modelling can assist in the understanding of this phenomenon.The edge-plasma transport codes present the most-advanced description of the plasma-wall interaction. However, the description of recycling remains partial: atomic reflection is already handled while molecular desorption is set ad-hoc by the code user. This PhD focuses on the development of an extension of the SolEdge2D-EIRENE transport code, named D-WEE, whose goal is to model the dynamics of desorption.To initialise D-WEE, a sequence of plasma discharges is simulated with D-WEE to model a tokamak operation. The simulated wall dynamics during those discharges is studied, reveling some interesting behaviours that could impact the reactor operation. To assess the relevance of the simulated wall dynamics, a confrontation to post-pulse experimental pressure measurement is performed which reveals a qualitative agreement between the temporal pressure drop obtained in the simulation (with a $t^{-0.8}$ trend) and the one observed experimentally under ILW configuration. The retention rate during the discharge is also studied and reproduces qualitatively the experimental trends., Dans les réacteurs à fusion nucléaire, un échange constant de particules se développe entre le plasma et la paroi. Ce phénomène, appelé recyclage, présente un intérêt crucial pour ces réacteurs car, une fois le plasma établi, le recyclage représente la principale source de particules pour le plasma. Une connaissance complète du recyclage est donc essentielle pour assurer un contrôle fiable de la densité plasma ainsi qu'une performance optimale du réacteur. Cependant, les études in-situ du recyclage demeurent complexes. La modélisation numérique peut assister dans la compréhension de ce phénomène.Les codes de transport de plasma de bord présentent la description la plus avancée de l’interaction plasma-paroi. La description du recyclage reste néanmoins partielle : la réflexion atomique est déjà traitée tandis que la désorption moléculaire est fixée ad-hoc par l’utilisateur. Cette thèse de doctorat se concentre sur le développement d’une extension au code de transport SolEdge2D-EIRENE, dénommée D-WEE, dont l’objectif est de modéliser la dynamique de la désorption.Afin d’initialiser D-WEE, une séquence de décharges plasma est simulée pour modéliser l’opération d’un tokamak. La dynamique simulée pendant ces décharges est étudiée, révélant des comportements intéressants qui pourraient impacter l’opération du réacteur. Pour évaluer la pertinence de la simulation, une confrontation avec l'expérience est effectuée et révèle un accord qualitatif entre la chute de pression post-décharge simulée (avec une tendance en $t^{-0.8}$) et celle observée expérimentalement. Le taux de rétention simulé pendant la décharge est étudié et présente un accord qualitatif avec l'expérience.

Background: Musculoskeletal disorders caused by osteoarthritis (MSDs/OA) are a growing problem in the modern industrialized society in Canada. Overall aging of the general population and a progressive lack of exercise contribute to this alarming increase. Moreover, a range of chronic conditions including cardiovascular and mental diseases show significantly higher comorbidity with MSDs/OA. Conventional medical treatment for MSDs/OA includes nonsteroidal anti-inflammatory drugs and opiate pain killers. These drugs have major drawbacks such as a relative lack of efficacy, potential for addiction, and even death (Vioxx scandal). Photobiomodulation (PBM) was discovered over 50 years ago but has still not attained widespread acceptance by the medical community. This is partly due to uncertainty about the precise molecular mechanisms of action and a bewildering array of different wavelengths and dosimetric parameters employed in reported studies. Objective: The goal of this review was to survey literature reports of PBM, also known as low-level laser therapy used for treatment of MSDs/OA, concentrating on the growth over time, different wavelengths employed, and application to different joints. Methods: We searched the PubMed database for publication of study on PBM to treat the most common joints. Results: We show that the field of PBM to treat MSDs/OA is expanding exponentially over the past 20 years. A trend has emerged over time for more power to achieve better effective treatments, and the understanding of the physiological effect of safe parameters has improved. There is, however, no consensus on the best set of parameters to treat a specific patient indication. Conclusions: Finally, we highlight gaps in our knowledge and the barriers to further clinical trials. We suggest that the growing body of evidence indicating efficacy, and the almost total lack of side effects, should encourage continued clinical research to support clinical applications where better rehabilitation treatments are much needed.

International audience; In order to improve cross-field transport description, drifts and currents have been implemented in SOLEDGE2D-EIRENE. The derivation of an equation for the electric potential is recalled. The resolution of current equation is tested in a simple slab case. WEST divertor simulations in forward-B and reverse-B fields are also discussed. A significant increase of ExB shear is observed in the forward-B configuration that could explain a favorable L-H transition in this case.

International audience

International audience; no abstract

Dans cet article les auteurs témoignent de leur passage en CLSC comme psychologues cliniciens et interrogent certains fondements idéologiques du CLSC ayant pour conséquence l'évacuation des services psycho-cliniques. D'après eux, des éléments majeurs de « l'approche CLSC » — tels la multidisciplmarité, l'intervention globale et la programmation — conduisent à nier la dimension proprement psychique de l'être humain et à prendre des décisions contestables en matière de santé mentale dans la mesure où, par exemple, les demandes individuelles de parler semblent devoir ne trouver aucune réponse dans le réseau public. Quels seraient les enjeux sous-jacents au fait que la volonté d'offrir des services à des «personnes» coexiste avec l'exclusion de ces personnes comme sujets parlants, tout en passant outre radicalement à la demande des usagers., SUMMARYIn this article, the authors relate their experience as clinical psychologists in a CLSC. The study questions certain ideological foundations of CLSCs which, as a consequence, entirely discard psycho-clinical services. According to the authors, the major elements of the "CLSC approach" — namely multidisci-plinarity, global intervention and programming — lead to the denial of a person's psychic dimension. As well, the authors argue that this approach is the source of questionable decisions in the area of mental health; for example, individual requests to talk freely seem to be ignored in the public health care system. The authors raise the underlying issues surrounding the coexistence of willingness to offer services to "people" on one hand and exclusion of these people as free-talking subjects (sujets parlants) on the other, while at the same time requests of clients to do so are totally neglected

The dynamics of HI photodissociation following absorption in the A band (200 to 300 nm) was investigated by Doppler spectroscopy at the Lyman α transition of the H-atom photofragments. Measurements of both the branching ratios for the formation of spin-orbit excited I(2P1/2) and ground state I(2P3/2) atoms and the angular distributions of the recoil velocity for these two photofragment channels were obtained at nine photolysis wavelengths between 212.5 and 266 nm. These results show that ground state products result from a transition of perpendicular symmetry (ΔΩ=1), while the excited state atoms are produced from a parallel transition (ΔΩ=0). These experimental results, in combination with total absorption cross section data obtained prior to the present study, have enabled a calculation of the potential curves for the dissociative excited states. The outcome of the calculation was found to be in good qualitative agreement with the model of HI electronic structure originally suggested by Mulliken.

Identifiant de l'opération archéologique : 2945 Date de l'opération : 2009 (SD) En 2006, lors d'un diagnostic archéologique réalisé sous la direction de Christophe Maniquet (INRAP) aux abords de l'église de Lupersat, des blocs de grand appareil antique en granite avaient été retrouvés agencés dans un sondage situé au pied du transept sud de l'église. Ce secteur n'était finalement pas concerné par la réalisation d'une fouille archéologique préventive, mais il était néanmoins intéressant de réa...

Identifiant de l'opération archéologique : 122365 Date de l'opération : 2005 (SD) Parmi les différents édifices ruinés du château de Crozant, un vestige de maçonnerie verticale, communément appelé « le contrefort », était souvent interprété comme une petite tour ou une guette flanquant l'enceinte ouest du site castral. L'étude archéologique du bâti menée en 2004 lors de la cristallisation des maçonneries ayant montré que l'on avait peut-être affaire là à une porte, un sondage archéologique a ...

Identifiant de l'opération archéologique : 2710 Date de l'opération : 2006 (PI) La crypte archéologique de la place de la République abrite les vestiges d'une partie de l'ancienne abbaye Saint-Martial. Ces vestiges (sépulcre de saint Martial, Saint-Pierre-du-Sépulcre et la chapelle Saint-Benoît) sont le résultat de plusieurs campagnes de fouilles menées de 1960 à 1974 dans des conditions très diverses. Plus de quarante ans après la découverte du sépulcre et des édifices attenants, il est appa...

Date de l'opération : 2006 (EX) Situé à deux kilomètres à l'est de la ville de La Souterraine, le château de Bridiers se compose d'une imposante tour maîtresse et d'une enceinte polygonale flanquée aux angles de petites tours circulaires. Cependant, si la vicomté de Bridiers est attestée dès le XIes., le château lui-même n'est pas antérieur à la fin du XIVes. ou au début du XVes. Il s'agit apparemment d'un château « neuf », construit ex nihilo à 800 m à l'...

Identifiant de l'opération archéologique : 122331 Date de l'opération : 2005 (PI) Dans le cadre de « l’inventaire général du patrimoine architectural et mobilier de la commune de Felletin » engagé en 2002, la ville de Felletin, le conseil général de la Creuse et la DRAC du Limousin pour l’Etat ont souhaité la réalisation d'une étude historique et documentaire de la ville, en orientant les problématiques sur la question des origines et de la genèse de la ville médiévale de Felletin qui devait ...

Identifiant de l'opération archéologique : 122628 Date de l'opération : 2005 (SD) Dans le cadre d'une étude préalable concernant la mise en valeur de la tour du Plô, l'architecte en chef des Monuments historiques a souhaité la réalisation d'un sondage archéologique afin de reconnaître la stratigraphie interne de la tour et d'identifier un éventuel niveau de sol originel. Probablement bâtie au début du XIIIe s., la tour du Plô est une tour maîtresse carrée de 8 m de côté, dotée de contreforts ...

Identifiant de l'opération archéologique : 2674 Date de l'opération : 2006 (SU) Dégagée en grande partie lors d'un sondage réalisé en 2005 par Guillaume Demeure (BSR 2005 : 26-27), la porte III est la dernière des trois portes principales jalonnant l'accès à la partie septentrionale du site de Crozant. Il s'agit d'une tour-porte quadrangulaire de 8,70 m sur 5,60 m, composée à l'ouest d'un passage de 2,50 m de large, et à l'ouest d'une chambre de tir équipée de trois archères à embrasures tria...

Recent advances and breakthroughs achieved in optical fiber technology have led to the advent of a new generation of fiber systems—Multiaccess Optical Fiber Networks.The huge bandwidth of these networks is revolutionizing the capability of individual nodes, and not surprisingly, multiaccess networks have become the subject of intense activity in the optical fiber communication engineering. The purpose of this tutorial paper is to acquaint the uninitiated reader with the basic concepts as well as the most recent progress of multiple access techniques applied to these networks. It also provides some insights into their characteristics relevant to the design engineer. The four basic multiple access techniques based on wavelength, subcarrier, time, and code degrees of freedom are reviewed theoretically and examples of systems that have been implemented so far are described. However, due to present-day technological limitations, these four basic techniques cannot yet be fully exploited to provide the optimum network performance they can theoretically offer. Therefore,hybridmultiple access schemes that combine these basic techniques in order to benefit from the advantages of each scheme while mitigating the drawbacks of the other ones have been proposed in the professional literature. These hybrid multiple access techniques are also surveyed in this paper.

International audience

A cost comparison for different broadband access network configurations in the context of fiber-in-the-loop (FITL) is presented. The basic architecture and features of the asynchronous transfer mode (ATM) passive optical network (APON) are described. The design objectives of each of the APON building blocks are clarified, and their relation to the system philosophy is indicated. The building blocks include systems for transport over the PON, operation of the user equipment, and interworking with existing networks. >

Le Mildiou de la vigne, causé par un oomycète parasite obligatoire, Plasmopara viticola, est une des maladies les plus redoutées par les viticulteurs. Son apparition est occasionnée par des éclaboussures de pluie et de terre sur les tissues de la vigne après les fortes précipitations véhiculant les zoospores infectieuses présentes à la surface du sol. Certaines variétés comme le Chasselas (V. vinifera) sont sensibles au mildiou et laissent P. viticola germer et se développer. D’autres variétés, dont le Solaris, un cépage interspécifique, montrent des caractères de résistance par la formation de nécroses au niveau de sites d’infection et d’enkystement de zoospores de P. viticola, empêchant le développement du pathogène. Il est maintenant admis que l’accumulation de stilbènes dans les feuilles de vigne est corrélée à la résistance de la vigne contre le pathogène. Les méthodes d’analyse chromatographique couplée à la spectrométrie de masse (LC-ESI-MS et LC-APPI-MS) nous ont permis l’identification de nouvelles substances induites lors de la défense de la vigne contre P. viticola : -la trans-δ-viniférine, le trans-δ-resvépterol et le δ-viniférinol, qui sont aussi des produits obtenus in vitro par oxydation enzymatique d’un mélange de trans¬resvératrol et de trans-pterostilbène. -le trans-ε-resvépterol, 11 formes de resvératrolosides, 3 trimères de resvératrol dont l’α-viniférine, 7 dimères de resvératrol ayant des analogies avec l’ε-viniférine et 4 lignanes. Parmi les composés isolés d’écorce de bois de vigne, l’ampélopsine A, l’hopéaphénol, la vitisine A et les tétramères de resvératrol TT2 et TT2’, seul TT2 étant induit dans la feuille infectée. Néanmoins, l’hopéaphénol, la vitisine A et le mélange de TT2-TT2’ montrent des activités biologiques réduisant la motilité des zoospores de P. viticola. L’acide β-aminobutyrique (BABA) induit l’accumulation de lignanes et de stilbènes dans les feuilles de Chasselas infectées. Une nouvelle stratégie de synthèse du trans-pterostilbène a été élaborée grâce à un double couplage de Heck (rendement total : 11% ). L’origine du pterostibène dans la feuille de vigne infectée est aussi discutée. Downy mildew, caused by an obligatory oomycete, Plasmopara viticola, is a worldwidely distributed grapevine disease. This grapevine disease appears after strong rainy periods which allow zoospores migration from the soil to the plant. Some cultivars as Chasselas (V. vinifera) are sensitive to downy mildew and cannot avoid P. viticola germination and development. Whereas other cultivars as Solaris, an interspecific variety, show resistance capacities with necrosis formation on the infection sites of P. viticola, avoiding the pathogen development. Chromatographic methods coupled to mass spectrometry (LC-APPI-MS and LC-ESI-MS) allowed us to identify new induced substances involved in grapevine plants defense against P. viticola : -trans-δ-viniferin, trans-δ-resvepterol and δ-viniferinol, that we could obtain by in vitro oxidative dimerisation of trans-resveratrol and trans-pterostilbene. -trans-ε-resvepterol, 11 resveratroloside forms, 3 resveratrol trimers among which the α-viniferin has been identified, 7 resveratrol dehydrodimers as ε-viniferin analogues and 4 lignans. Among isolated compounds from grapevine’s bark, ampelopsin A, hopeaphenol, vitisin A and two resveratrol tetramers TT2 and TT2’, only TT2 should be induced in infected grapevine leaves. However, hopeaphenol, vitisin A and a mixture of TT2 and TT2’ show biological activities decreasing the P. viticola zoospores mobility. β-Aminobutyric (BABA) induced the accumulation of lignans and stilbenes in infected Chasselas leaves. A new strategy of trans-pterostilbene synthesis has been investigated through a double Heck reaction (overall yield : 11%). The pterostilbene origin in the infected grapevine leaves is discussed.

Rapports

Eine 2005 an der Stelle des ehemaligen Baptisteriums von Limoges durchgeführte archäologische Plangrabung führte zur Aufdeckung eines ausgedehnten und atypischen Bauwerkes. Das genannte Baptisterium besteht aus einem hexagonalen Saal von mehr als 10 m Durchmesser, in dessen Mitte sich das kreisrunde Taufbecken befand, und sechs quadratischen Nebenräumen, die sich zu dem zentralen Hexagon hin öffneten. Der Zugang zum Baptisterium befand sich im Westen. Im Verlauf des frühen Mittelalters wurde das Baptisterium in eine Kirche umgewandelt und dabei am Ostende durch eine halbrunde Apsis erweitert. Gegen Ende des 12. oder zu Beginn des 13. Jahrhunderts wurde die ganze Anlage systematisch zurückgebaut, um einer kleinen Pfarrkirche Platz zu machen., During the programmed excavation carried in 2005 on the spot of the former baptistry at Limoges, a vast and atypical building has been discovered. It consisted in a hexagonal room of more than 10 m diameter, in which a circular pool and six quadrangular rooms around it were built, opened towards the central hexagon. The entrance was situated west. During the early Middle Age, it was converted into a church and a semi-circular apse was added at the eastern end. The whole building at last has been entirely dismantled at the end of the 12th c. or early 13th c. and a small parish church has been established., La fouille archéologique, menée en 2005 à l’emplacement de l’ancien baptistère de Limoges, a permis la découverte d’un vaste édifice atypique. Ce baptistère était composé d’une salle hexagonale de plus de 10 m de diamètre - au centre de laquelle se trouvait une piscine baptismale de forme circulaire - et de six pièces périphériques quadrangulaires ouvrant sur l’hexagone central. L’entrée dans le baptistère s’effectuait à l’ouest. Dans le courant du haut Moyen Âge, ce baptistère fut transformé en église et agrandi d’une abside semi-circulaire à son extrémité est. L’ensemble de l’édifice fut enfin méthodiquement démonté à la fin du XIIe s. ou au début du XIIIe s. pour laisser place à une petite église paroissiale., Denis Julien. Le baptistère de Limoges (Haute-Vienne). In: Gallia, tome 63, 2006. pp. 125-129.

Optical bidirectional transmission over a wide-range high splitting passive optical network (PON) is discussed. As major issues, the optical amplification of the burst-mode upstream signal and the nonintrusive ranging were identified and solutions to overcome them were proposed. Further lab experiments are planned and results will be presented at the conference.

Endothelial cells play a central role in chronic inflammation: for example, they express adhesion molecules and present chemokines leading to enhanced leukocyte recruitment into tissues. Numerous markers of endothelial cells have been reported but there has been a lack of comparative data on their specificity. The present study compared the specificity of seven endothelial cell markers in the rheumatoid synovium and the colon of patients with Crohn's disease. These markers were: the sulphated epitope MECA-79, the Duffy antigen receptor for chemokines (DARC), von Willebrand factor, CD31 (PECAM-1), CD34, CD105 (endoglin) and CD146. MECA-79, DARC and von Willebrand factor showed a specific endothelial cell distribution. MECA-79, which recognizes sulphated ligands for leukocyte adhesion receptor L-selectin (CD62L), was selective for a subset of venules in highly inflamed tissue and was present in rheumatoid but not control osteoarthritic synovia. DARC was also specific for venules but had a more widespread distribution than MECA-79, and was present in rheumatoid and control synovia. The other markers all labelled endothelial cells in venules, arterioles and capillaries. However, they also localized to other cell types. For example, CD34 stained fibroblasts, CD146 was expressed by the pericytes and smooth muscle cells of vessel walls and CD31 and CD105 labelled a broad range of cell types.

Subcarrier multiple access (SCMA) is described. It is a flexible access technique for passive optical networks (PONs), both for fiber-to-the home and fiber-to-the curb architectures. The main advantages of SCMA are the independence of the channels, which yields flexibility with respect to modulation format and evolution scenario, and the absence of synchronization between the different subscribers. Some results of SCMA experiments are presented. The capability of broadband channels is discussed, taking into account the optical interference effect. A comparison is made with other access techniques. >

The first study of a diode-pumped Neodymium-doped Lanthanum Scandium Borate oscillator based on the grazing-incidence slab laser design is reported. An experimental method to determine the power of the thermal lens in this new system is described. It is shown that saturable absorption of Cr4+:YAG can be used as a passive Q-switch to generate pulses at 1.06 micrometers with adjustable duration from 18 to 76 nsec.

A hybrid diode-pumped laser, incorporating an end-pumped Nd:YAG rod and a side-pumped slab of Nd:YVO 4 used at grazing incidence, has been operated at a repetition rate of 1000 pps. With an average power of 5 W deposited in the Nd:YAG, the output power of 1.8 W was twice that obtained when only the Nd:YVO 4 was pumped. With a pulse duration of 4.5 ns, this system provides a peak power of 400 kW in a near diffraction limited beam.

Passive Optical Networks (PONs) have been demonstrated to be a cost-attractive approach for the deployment of Fiber- In-The-Loop systems (FITL) having POTS services capability. In the future these systems must be able to carry broadband services in ATM format as defined by CCITT. The present paper describes an ATM-based PON (APON) and presents the results of feasibility tests for the most critical parts of the system: high-speed medium access protocol for upstream transmission(TDMA), burst mode clock synchronisation technique and high-speed electro-optic transceivers applicable to burst mode transmission. System design options such as the downstream and upstream bit rates, the sharing factor and the multiplexingtechnique used for the bidirectional transport of ATM cells are discussed. Issues such as analog CATV services delivery andthe provision of digital video-on-demand (VOD) are covered as well.1. INTRODUCTIONDeployment of fiber in the local loop has become of major interest during the last years. A large number of papers 1..6

Techniques for multiple access over passive optical access networks, between the central office (CO)and the subscriber premises, have been the subject of considerable recent interest. Among the distinct proposals, time-division multiple access (TDMA)1 and wavelength-division multiple access (WDMA)2 have attracted much attention and have been demonstrated experimentally.

Endothelial cells are active participants in chronic inflammatory diseases. These cells undergo phenotypic changes that can be characterised as activated, angiogenic, apoptotic and leaky. In the present review, these phenotypes are described in the context of human rheumatoid arthritis as the disease example. Endothelial cells become activated in rheumatoid arthritis pathophysiology, expressing adhesion molecules and presenting chemokines, leading to leukocyte migration from the blood into the tissue. Endothelial cell permeability increases, leading to oedema formation and swelling of the joints. These cells proliferate as part of the angiogenic response and there is also a net increase in the turnover of endothelial cells since the number of apoptotic endothelial cells increases. The endothelium expresses various cytokines, cytokine receptors and proteases that are involved in angiogenesis, proliferation and tissue degradation. Associated with these mechanisms is a change in the spectrum of genes expressed, some of which are relatively endothelial specific and others are widely expressed by other cells in the synovium. Better knowledge of molecular and functional changes occurring in endothelial cells during chronic inflammation may lead to the development of endothelium-targeted therapies for rheumatoid arthritis and other chronic inflammatory diseases.