941 resultados para test case optimization


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Un système efficace de sismique tridimensionnelle (3-D) haute-résolution adapté à des cibles lacustres de petite échelle a été développé. Dans le Lac Léman, près de la ville de Lausanne, en Suisse, des investigations récentes en deux dimension (2-D) ont mis en évidence une zone de faille complexe qui a été choisie pour tester notre système. Les structures observées incluent une couche mince (<40 m) de sédiments quaternaires sub-horizontaux, discordants sur des couches tertiaires de molasse pentées vers le sud-est. On observe aussi la zone de faille de « La Paudèze » qui sépare les unités de la Molasse du Plateau de la Molasse Subalpine. Deux campagnes 3-D complètes, d?environ d?un kilomètre carré, ont été réalisées sur ce site de test. La campagne pilote (campagne I), effectuée en 1999 pendant 8 jours, a couvert 80 profils en utilisant une seule flûte. Pendant la campagne II (9 jours en 2001), le nouveau système trois-flûtes, bien paramétrés pour notre objectif, a permis l?acquisition de données de très haute qualité sur 180 lignes CMP. Les améliorations principales incluent un système de navigation et de déclenchement de tirs grâce à un nouveau logiciel. Celui-ci comprend un contrôle qualité de la navigation du bateau en temps réel utilisant un GPS différentiel (dGPS) à bord et une station de référence près du bord du lac. De cette façon, les tirs peuvent être déclenchés tous les 5 mètres avec une erreur maximale non-cumulative de 25 centimètres. Tandis que pour la campagne I la position des récepteurs de la flûte 48-traces a dû être déduite à partir des positions du bateau, pour la campagne II elle ont pu être calculées précisément (erreur <20 cm) grâce aux trois antennes dGPS supplémentaires placées sur des flotteurs attachés à l?extrémité de chaque flûte 24-traces. Il est maintenant possible de déterminer la dérive éventuelle de l?extrémité des flûtes (75 m) causée par des courants latéraux ou de petites variations de trajet du bateau. De plus, la construction de deux bras télescopiques maintenant les trois flûtes à une distance de 7.5 m les uns des autres, qui est la même distance que celle entre les lignes naviguées de la campagne II. En combinaison avec un espacement de récepteurs de 2.5 m, la dimension de chaque «bin» de données 3-D de la campagne II est de 1.25 m en ligne et 3.75 m latéralement. L?espacement plus grand en direction « in-line » par rapport à la direction «cross-line» est justifié par l?orientation structurale de la zone de faille perpendiculaire à la direction «in-line». L?incertitude sur la navigation et le positionnement pendant la campagne I et le «binning» imprécis qui en résulte, se retrouve dans les données sous forme d?une certaine discontinuité des réflecteurs. L?utilisation d?un canon à air à doublechambre (qui permet d?atténuer l?effet bulle) a pu réduire l?aliasing observé dans les sections migrées en 3-D. Celui-ci était dû à la combinaison du contenu relativement haute fréquence (<2000 Hz) du canon à eau (utilisé à 140 bars et à 0.3 m de profondeur) et d?un pas d?échantillonnage latéral insuffisant. Le Mini G.I 15/15 a été utilisé à 80 bars et à 1 m de profondeur, est mieux adapté à la complexité de la cible, une zone faillée ayant des réflecteurs pentés jusqu?à 30°. Bien que ses fréquences ne dépassent pas les 650 Hz, cette source combine une pénétration du signal non-aliasé jusqu?à 300 m dans le sol (par rapport au 145 m pour le canon à eau) pour une résolution verticale maximale de 1.1 m. Tandis que la campagne I a été acquise par groupes de plusieurs lignes de directions alternées, l?optimisation du temps d?acquisition du nouveau système à trois flûtes permet l?acquisition en géométrie parallèle, ce qui est préférable lorsqu?on utilise une configuration asymétrique (une source et un dispositif de récepteurs). Si on ne procède pas ainsi, les stacks sont différents selon la direction. Toutefois, la configuration de flûtes, plus courtes que pour la compagne I, a réduit la couverture nominale, la ramenant de 12 à 6. Une séquence classique de traitement 3-D a été adaptée à l?échantillonnage à haute fréquence et elle a été complétée par deux programmes qui transforment le format non-conventionnel de nos données de navigation en un format standard de l?industrie. Dans l?ordre, le traitement comprend l?incorporation de la géométrie, suivi de l?édition des traces, de l?harmonisation des «bins» (pour compenser l?inhomogénéité de la couverture due à la dérive du bateau et de la flûte), de la correction de la divergence sphérique, du filtrage passe-bande, de l?analyse de vitesse, de la correction DMO en 3-D, du stack et enfin de la migration 3-D en temps. D?analyses de vitesse détaillées ont été effectuées sur les données de couverture 12, une ligne sur deux et tous les 50 CMP, soit un nombre total de 600 spectres de semblance. Selon cette analyse, les vitesses d?intervalles varient de 1450-1650 m/s dans les sédiments non-consolidés et de 1650-3000 m/s dans les sédiments consolidés. Le fait que l?on puisse interpréter plusieurs horizons et surfaces de faille dans le cube, montre le potentiel de cette technique pour une interprétation tectonique et géologique à petite échelle en trois dimensions. On distingue cinq faciès sismiques principaux et leurs géométries 3-D détaillées sur des sections verticales et horizontales: les sédiments lacustres (Holocène), les sédiments glacio-lacustres (Pléistocène), la Molasse du Plateau, la Molasse Subalpine de la zone de faille (chevauchement) et la Molasse Subalpine au sud de cette zone. Les couches de la Molasse du Plateau et de la Molasse Subalpine ont respectivement un pendage de ~8° et ~20°. La zone de faille comprend de nombreuses structures très déformées de pendage d?environ 30°. Des tests préliminaires avec un algorithme de migration 3-D en profondeur avant sommation et à amplitudes préservées démontrent que la qualité excellente des données de la campagne II permet l?application de telles techniques à des campagnes haute-résolution. La méthode de sismique marine 3-D était utilisée jusqu?à présent quasi-exclusivement par l?industrie pétrolière. Son adaptation à une échelle plus petite géographiquement mais aussi financièrement a ouvert la voie d?appliquer cette technique à des objectifs d?environnement et du génie civil.<br/><br/>An efficient high-resolution three-dimensional (3-D) seismic reflection system for small-scale targets in lacustrine settings was developed. In Lake Geneva, near the city of Lausanne, Switzerland, past high-resolution two-dimensional (2-D) investigations revealed a complex fault zone (the Paudèze thrust zone), which was subsequently chosen for testing our system. Observed structures include a thin (<40 m) layer of subhorizontal Quaternary sediments that unconformably overlie southeast-dipping Tertiary Molasse beds and the Paudèze thrust zone, which separates Plateau and Subalpine Molasse units. Two complete 3-D surveys have been conducted over this same test site, covering an area of about 1 km2. In 1999, a pilot survey (Survey I), comprising 80 profiles, was carried out in 8 days with a single-streamer configuration. In 2001, a second survey (Survey II) used a newly developed three-streamer system with optimized design parameters, which provided an exceptionally high-quality data set of 180 common midpoint (CMP) lines in 9 days. The main improvements include a navigation and shot-triggering system with in-house navigation software that automatically fires the gun in combination with real-time control on navigation quality using differential GPS (dGPS) onboard and a reference base near the lake shore. Shots were triggered at 5-m intervals with a maximum non-cumulative error of 25 cm. Whereas the single 48-channel streamer system of Survey I requires extrapolation of receiver positions from the boat position, for Survey II they could be accurately calculated (error <20 cm) with the aid of three additional dGPS antennas mounted on rafts attached to the end of each of the 24- channel streamers. Towed at a distance of 75 m behind the vessel, they allow the determination of feathering due to cross-line currents or small course variations. Furthermore, two retractable booms hold the three streamers at a distance of 7.5 m from each other, which is the same distance as the sail line interval for Survey I. With a receiver spacing of 2.5 m, the bin dimension of the 3-D data of Survey II is 1.25 m in in-line direction and 3.75 m in cross-line direction. The greater cross-line versus in-line spacing is justified by the known structural trend of the fault zone perpendicular to the in-line direction. The data from Survey I showed some reflection discontinuity as a result of insufficiently accurate navigation and positioning and subsequent binning errors. Observed aliasing in the 3-D migration was due to insufficient lateral sampling combined with the relatively high frequency (<2000 Hz) content of the water gun source (operated at 140 bars and 0.3 m depth). These results motivated the use of a double-chamber bubble-canceling air gun for Survey II. A 15 / 15 Mini G.I air gun operated at 80 bars and 1 m depth, proved to be better adapted for imaging the complexly faulted target area, which has reflectors dipping up to 30°. Although its frequencies do not exceed 650 Hz, this air gun combines a penetration of non-aliased signal to depths of 300 m below the water bottom (versus 145 m for the water gun) with a maximum vertical resolution of 1.1 m. While Survey I was shot in patches of alternating directions, the optimized surveying time of the new threestreamer system allowed acquisition in parallel geometry, which is preferable when using an asymmetric configuration (single source and receiver array). Otherwise, resulting stacks are different for the opposite directions. However, the shorter streamer configuration of Survey II reduced the nominal fold from 12 to 6. A 3-D conventional processing flow was adapted to the high sampling rates and was complemented by two computer programs that format the unconventional navigation data to industry standards. Processing included trace editing, geometry assignment, bin harmonization (to compensate for uneven fold due to boat/streamer drift), spherical divergence correction, bandpass filtering, velocity analysis, 3-D DMO correction, stack and 3-D time migration. A detailed semblance velocity analysis was performed on the 12-fold data set for every second in-line and every 50th CMP, i.e. on a total of 600 spectra. According to this velocity analysis, interval velocities range from 1450-1650 m/s for the unconsolidated sediments and from 1650-3000 m/s for the consolidated sediments. Delineation of several horizons and fault surfaces reveal the potential for small-scale geologic and tectonic interpretation in three dimensions. Five major seismic facies and their detailed 3-D geometries can be distinguished in vertical and horizontal sections: lacustrine sediments (Holocene) , glaciolacustrine sediments (Pleistocene), Plateau Molasse, Subalpine Molasse and its thrust fault zone. Dips of beds within Plateau and Subalpine Molasse are ~8° and ~20°, respectively. Within the fault zone, many highly deformed structures with dips around 30° are visible. Preliminary tests with 3-D preserved-amplitude prestack depth migration demonstrate that the excellent data quality of Survey II allows application of such sophisticated techniques even to high-resolution seismic surveys. In general, the adaptation of the 3-D marine seismic reflection method, which to date has almost exclusively been used by the oil exploration industry, to a smaller geographical as well as financial scale has helped pave the way for applying this technique to environmental and engineering purposes.<br/><br/>La sismique réflexion est une méthode d?investigation du sous-sol avec un très grand pouvoir de résolution. Elle consiste à envoyer des vibrations dans le sol et à recueillir les ondes qui se réfléchissent sur les discontinuités géologiques à différentes profondeurs et remontent ensuite à la surface où elles sont enregistrées. Les signaux ainsi recueillis donnent non seulement des informations sur la nature des couches en présence et leur géométrie, mais ils permettent aussi de faire une interprétation géologique du sous-sol. Par exemple, dans le cas de roches sédimentaires, les profils de sismique réflexion permettent de déterminer leur mode de dépôt, leurs éventuelles déformations ou cassures et donc leur histoire tectonique. La sismique réflexion est la méthode principale de l?exploration pétrolière. Pendant longtemps on a réalisé des profils de sismique réflexion le long de profils qui fournissent une image du sous-sol en deux dimensions. Les images ainsi obtenues ne sont que partiellement exactes, puisqu?elles ne tiennent pas compte de l?aspect tridimensionnel des structures géologiques. Depuis quelques dizaines d?années, la sismique en trois dimensions (3-D) a apporté un souffle nouveau à l?étude du sous-sol. Si elle est aujourd?hui parfaitement maîtrisée pour l?imagerie des grandes structures géologiques tant dans le domaine terrestre que le domaine océanique, son adaptation à l?échelle lacustre ou fluviale n?a encore fait l?objet que de rares études. Ce travail de thèse a consisté à développer un système d?acquisition sismique similaire à celui utilisé pour la prospection pétrolière en mer, mais adapté aux lacs. Il est donc de dimension moindre, de mise en oeuvre plus légère et surtout d?une résolution des images finales beaucoup plus élevée. Alors que l?industrie pétrolière se limite souvent à une résolution de l?ordre de la dizaine de mètres, l?instrument qui a été mis au point dans le cadre de ce travail permet de voir des détails de l?ordre du mètre. Le nouveau système repose sur la possibilité d?enregistrer simultanément les réflexions sismiques sur trois câbles sismiques (ou flûtes) de 24 traces chacun. Pour obtenir des données 3-D, il est essentiel de positionner les instruments sur l?eau (source et récepteurs des ondes sismiques) avec une grande précision. Un logiciel a été spécialement développé pour le contrôle de la navigation et le déclenchement des tirs de la source sismique en utilisant des récepteurs GPS différentiel (dGPS) sur le bateau et à l?extrémité de chaque flûte. Ceci permet de positionner les instruments avec une précision de l?ordre de 20 cm. Pour tester notre système, nous avons choisi une zone sur le Lac Léman, près de la ville de Lausanne, où passe la faille de « La Paudèze » qui sépare les unités de la Molasse du Plateau et de la Molasse Subalpine. Deux campagnes de mesures de sismique 3-D y ont été réalisées sur une zone d?environ 1 km2. Les enregistrements sismiques ont ensuite été traités pour les transformer en images interprétables. Nous avons appliqué une séquence de traitement 3-D spécialement adaptée à nos données, notamment en ce qui concerne le positionnement. Après traitement, les données font apparaître différents faciès sismiques principaux correspondant notamment aux sédiments lacustres (Holocène), aux sédiments glacio-lacustres (Pléistocène), à la Molasse du Plateau, à la Molasse Subalpine de la zone de faille et la Molasse Subalpine au sud de cette zone. La géométrie 3-D détaillée des failles est visible sur les sections sismiques verticales et horizontales. L?excellente qualité des données et l?interprétation de plusieurs horizons et surfaces de faille montrent le potentiel de cette technique pour les investigations à petite échelle en trois dimensions ce qui ouvre des voies à son application dans les domaines de l?environnement et du génie civil.

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Optimization models in metabolic engineering and systems biology focus typically on optimizing a unique criterion, usually the synthesis rate of a metabolite of interest or the rate of growth. Connectivity and non-linear regulatory effects, however, make it necessary to consider multiple objectives in order to identify useful strategies that balance out different metabolic issues. This is a fundamental aspect, as optimization of maximum yield in a given condition may involve unrealistic values in other key processes. Due to the difficulties associated with detailed non-linear models, analysis using stoichiometric descriptions and linear optimization methods have become rather popular in systems biology. However, despite being useful, these approaches fail in capturing the intrinsic nonlinear nature of the underlying metabolic systems and the regulatory signals involved. Targeting more complex biological systems requires the application of global optimization methods to non-linear representations. In this work we address the multi-objective global optimization of metabolic networks that are described by a special class of models based on the power-law formalism: the generalized mass action (GMA) representation. Our goal is to develop global optimization methods capable of efficiently dealing with several biological criteria simultaneously. In order to overcome the numerical difficulties of dealing with multiple criteria in the optimization, we propose a heuristic approach based on the epsilon constraint method that reduces the computational burden of generating a set of Pareto optimal alternatives, each achieving a unique combination of objectives values. To facilitate the post-optimal analysis of these solutions and narrow down their number prior to being tested in the laboratory, we explore the use of Pareto filters that identify the preferred subset of enzymatic profiles. We demonstrate the usefulness of our approach by means of a case study that optimizes the ethanol production in the fermentation of Saccharomyces cerevisiae.

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The amphibian micronucleus test has been widely used during the last 30 years to test the genotoxic properties of several chemicals and as a tool for ecogenotoxic monitoring. The vast majority of these studies were performed on peripheral blood of urodelan larvae and anuran tadpoles and to a lesser extent adults were also used. In this study, we developed protocols for measuring micronuclei in adult shed skin cells and larval gill cells of the Italian crested newt (Triturus carnifex). Amphibians were collected from ponds in two protected areas in Italy that differed in their radon content. Twenty-three adult newts and 31 larvae were captured from the radon-rich pond, while 20 adults and 27 larvae were taken from the radon-free site. The animals were brought to the laboratory and the micronucleus test was performed on peripheral blood and shed skins taken from the adults and on larval gills. Samples from the radon-rich site showed micronucleus frequencies higher than those from the radon-free site and the difference was statistically significant in gill cells (P < 0.00001). Moreover, the larval gills seem to be more sensitive than the adult tissues. This method represents an easy (and noninvasive in the case of the shed skin) application of the micronucleus assay that can be useful for environmental studies in situ. Environ. Mol. Mutagen. 56:412-417, 2015. © 2014 Wiley Periodicals, Inc.

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The evaluation of investments in advanced technology is one of the most important decision making tasks. The importance is even more pronounced considering the huge budget concerning the strategic, economic and analytic justification in order to shorten design and development time. Choosing the most appropriate technology requires an accurate and reliable system that can lead the decision makers to obtain such a complicated task. Currently, several Information and Communication Technologies (ICTs) manufacturers that design global products are seeking local firms to act as their sales and services representatives (called distributors) to the end user. At the same time, the end user or customer is also searching for the best possible deal for their investment in ICT's projects. Therefore, the objective of this research is to present a holistic decision support system to assist the decision maker in Small and Medium Enterprises (SMEs) - working either as individual decision makers or in a group - in the evaluation of the investment to become an ICT's distributor or an ICT's end user. The model is composed of the Delphi/MAH (Maximising Agreement Heuristic) Analysis, a well-known quantitative method in Group Support System (GSS), which is applied to gather the average ranking data from amongst Decision Makers (DMs). After that the Analytic Network Process (ANP) analysis is brought in to analyse holistically: it performs quantitative and qualitative analysis simultaneously. The illustrative data are obtained from industrial entrepreneurs by using the Group Support System (GSS) laboratory facilities at Lappeenranta University of Technology, Finland and in Thailand. The result of the research, which is currently implemented in Thailand, can provide benefits to the industry in the evaluation of becoming an ICT's distributor or an ICT's end user, particularly in the assessment of the Enterprise Resource Planning (ERP) programme. After the model is put to test with an in-depth collaboration with industrial entrepreneurs in Finland and Thailand, the sensitivity analysis is also performed to validate the robustness of the model. The contribution of this research is in developing a new approach and the Delphi/MAH software to obtain an analysis of the value of becoming an ERP distributor or end user that is flexible and applicable to entrepreneurs, who are looking for the most appropriate investment to become an ERP distributor or end user. The main advantage of this research over others is that the model can deliver the value of becoming an ERP distributor or end user in a single number which makes it easier for DMs to choose the most appropriate ERP vendor. The associated advantage is that the model can include qualitative data as well as quantitative data, as the results from using quantitative data alone can be misleading and inadequate. There is a need to utilise quantitative and qualitative analysis together, as can be seen from the case studies.

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This abstract presents how we redesigned, with user-centred design methods, the way we organize and present the content on the UOC Virtual Library website. The content is now offered in a way that is more intuitive, usable and easy to understand, based on criteria of customization, transparency and proximity.The techniques used to achieve these objectives included benchmarking, interviews and focus groups during the user requirement capture phase and user tests to assess the process and results.

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N = 1 designs imply repeated registrations of the behaviour of the same experimental unit and the measurements obtained are often few due to time limitations, while they are also likely to be sequentially dependent. The analytical techniques needed to enhance statistical and clinical decision making have to deal with these problems. Different procedures for analysing data from single-case AB designs are discussed, presenting their main features and revising the results reported by previous studies. Randomization tests represent one of the statistical methods that seemed to perform well in terms of controlling false alarm rates. In the experimental part of the study a new simulation approach is used to test the performance of randomization tests and the results suggest that the technique is not always robust against the violation of the independence assumption. Moreover, sensitivity proved to be generally unacceptably low for series lengths equal to 30 and 40. Considering the evidence available, there does not seem to be an optimal technique for single-case data analysis

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Leprosy is a contagious and chronic systemic granulomatous disease caused by Mycobacterium leprae (Hansen"s bacillus). It is transmitted from person to person and has a long incubation period (between two and six years). The disease presents polar clinical forms (the"multibacillary" lepromatous leprosy and the"paucibacillary" tuberculoid leprosy), as well as other intermediate forms with hybrid characteristics. Oral manifestations usually appear in lepromatous leprosy and occur in 20-60% of cases. They may take the form of multiple nodules (lepromas) that progress to necrosis and ulceration. The ulcers are slow to heal, and produce atrophic scarring or even tissue destruction. The lesions are usually located on the hard and soft palate, in the uvula, on the underside of the tongue, and on the lips and gums. There may also be destruction of the anterior maxilla and loss of teeth. The diagnosis, based on clinical suspicion, is confirmed through bacteriological and histopathological analyses, as well as by means of the lepromin test (intradermal reaction that is usually negative in lepromatous leprosy form and positive in the tuberculoid form). The differential diagnosis includes systemic lupus erythematosus, sarcoidosis, cutaneous leishmaniasis and other skin diseases, tertiary syphilis, lymphomas, systemic mycosis, traumatic lesions and malignant neoplasias, among other disorders. Treatment is difficult as it must be continued for long periods, requires several drugs with adverse effects and proves very expensive, particularly for less developed countries. The most commonly used drugs are dapsone, rifampicin and clofazimine. Quinolones, such as ofloxacin and pefloxacin, as well as some macrolides, such as clarithromycin and minocyclin, are also effective. The present case report describes a patient with lepromatous leprosy acquired within a contagious family setting during childhood and adolescence

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Tutkimuksen tavoitteena oli selvittää miten kehittää yrityksen nykyistä e-palvelujärjestelmää, Internet -teknologiaan perustuvaa sähköisiä kommunikaatio- ja tiedonjakojärjestelmää, yrityksen business-to-business asiakkuuksien johtamisessa. Tavoitteena oli myös luoda ehdotukset uusista e-palvelusopimusmalleista. Tutkimuksen teoriaosuudessa pyrittiin kehittämään aikaisempiin tutkimuksiin, tietokirjallisuuteen ja asiantuntijoihin perustuva viitekehysmalli. Empiirisessä osassa tutkimuksen tavoitteisiin pyrittiin haastattelemalla yrityksen asiakkaita ja henkilöstöä, sekä tarkastelemalla asiakaskontaktien nykyistä tilaa ja kehittymistä. Näiden tietojen perusteella selvitettiin e-palvelun käyttäjien tarpeita, profiilia ja valmiuksia palvelun käyttöön sekä palvelun nykyistä houkuttelevuutta. Tutkimuksen teoriaosan lähdeaineistona käytettiin kirjallisuutta, artikkeleita ja tilastoja asiakashallinnasta sekä e-palveluiden, erityisesti Internet ja verkkopalveluiden markkinoinnista, nykytilasta sekä palveluiden kehittämisestä. Lisäksi tutkittiin kirjallisuutta arvoverkostoanalyysistä, asiakkaan arvosta, informaatioteknologiasta, palvelun laadusta ja asiakastyytyväisyydestä. Tutkimuksen empiirinen osa perustuu yrityksen henkilöstöltä sekä asiakkailta haastatteluissa kerättyihin tietoihin, yrityksen ennalta keräämiin materiaaleihin sekä Taloustutkimuksen keräämiin tietoihin. Tutkimuksessa käytettiin case -menetelmää, joka oli yhdistelmä sekä kvalitatiivista että kvantitatiivista tutkimusta. Casen tarkoituksena oli testata mallin paikkansapitävyyttä ja käyttökelpoisuutta, sekä selvittää onko olemassa vielä muita tekijöitä, jotka vaikuttavat asiakkaan saamaan arvoon. Kvalitatiivinen aineisto perustuu teemahaastattelumenetelmää soveltaen haastateltuihin asiakkaisiin ja yrityksen työntekijöihin. Kvantitatiivinen tutkimus perustuu Taloustutkimuksen tutkimukseen ja yrityksen asiakaskontakteista kerättyyn tietoon. Haastatteluiden perusteella e-palvelut nähtiin hyödyllisinä ja tulevaisuudessa erittäin tärkeinä. E-palvelut nähdään yhtenä tärkeänä kanavana, perinteisten kanavien rinnalla, tehostaa business-to-business -asiakkuuksien johtamista. Tutkimuksen antamien tulosten mukaan asiakkaiden palveluun liittyvän tieto-, taito-, tarpeellisuus- ja kiinnostavuustasojen vaihtelevaisuus osoittaa selvän tarpeen eritasoisille e-palvelupaketti ratkaisuille. Tuloksista muodostettu ratkaisuehdotus käsittää neljän eri e-palvelupaketin rakentamisen asiakkaiden eri tarpeita mukaillen.

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Background: Vancomycin is a cornerstone antibiotic for the management of severe Gram positive infections. However, high doses of vancomycin are associated with a risk of nephrotoxicity. This study aimed to evaluate the relationship between the evolution of vancomycin trough concentration and the occurrence of nephrotoxicity, and to identify risk factors for both vancomycin-associated nephrotoxicity and vancomycin overexposure. Methods: A total of 1240 patients records from our hospital therapeutic drug monitoring database between 2007 and 2011 were screened and grouped according to predefined criteria defining vancomycin overexposure (one or more occurrence of a trough level ≥ 20 mg/L) and treatment-related nephrotoxicity (rise of serum creatinine by ≥ 50% over baseline). A representative sample of 150 cases was selected for in depth analysis. Weighted logistic regression analyses were used to test associations between vancomycin overexposure, nephrotoxicity and other predictors of interest. Results: Patients with high trough concentrations were found to be more likely to develop nephrotoxicity (odds ratio: 4.12; p <0.001). Specific risk factors, notably concomitant nephrotoxic treatments and comorbid conditions (heart failure), were found to independently increase the risk of either nephrotoxicity or vancomycin exposure. Finally, the exploration of temporal relationships between variations of vancomycin trough concentrations and creatinine levels were in line with circular causality with some antecedence of vancomycin on creatinine changes. Conclusion: Our results confirm the important nephrotoxic potential of vancomycin and indicate that the utilisation of this drug deserves thorough individualization for conditions susceptible to increase its concentration exposure and reactive adjustment based on therapeutic drug monitoring.

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OBJECTIVE: It has been suggested that Schistosoma mansoni, which is endemic in African fishing communities, might increase susceptibility to human immunodeficiency virus (HIV) acquisition. If confirmed, this would be of great public health importance in these high HIV-risk communities. This study was undertaken to determine whether S. mansoni infection is a risk factor for HIV infection among the fishing communities of Lake Victoria, Uganda. We conducted a matched case-control study, nested within a prospective HIV incidence cohort, including 50 HIV seroconverters (cases) and 150 controls during 2009-2011. METHODS: S. mansoni infection prior to HIV seroconversion was determined by measuring serum circulating anodic antigen (CAA) in stored serum. HIV testing was carried out using the Determine rapid test and infection confirmed by enzyme-linked immunosorbent assays. RESULTS: About 49% of cases and 52% of controls had S. mansoni infection prior to HIV seroconversion (or at the time of a similar study visit, for controls): odds ratio, adjusting for ethnicity, religion, marital status, education, occupation, frequency of alcohol consumption in previous 3 months, number of sexual partners while drunk, duration of stay in the community, and history of schistosomiasis treatment in the past 2 years was 1.23 (95% CI 0.3-5.7) P = 0.79. S. mansoni infections were chronic (with little change in status between enrolment and HIV seroconversion), and there was no difference in median CAA concentration between cases and controls. CONCLUSIONS: These results do not support the hypothesis that S. mansoni infection promotes HIV acquisition.

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Aim The aim of this study was to test different modelling approaches, including a new framework, for predicting the spatial distribution of richness and composition of two insect groups. Location The western Swiss Alps. Methods We compared two community modelling approaches: the classical method of stacking binary prediction obtained fromindividual species distribution models (binary stacked species distribution models, bS-SDMs), and various implementations of a recent framework (spatially explicit species assemblage modelling, SESAM) based on four steps that integrate the different drivers of the assembly process in a unique modelling procedure. We used: (1) five methods to create bS-SDM predictions; (2) two approaches for predicting species richness, by summing individual SDM probabilities or by modelling the number of species (i.e. richness) directly; and (3) five different biotic rules based either on ranking probabilities from SDMs or on community co-occurrence patterns. Combining these various options resulted in 47 implementations for each taxon. Results Species richness of the two taxonomic groups was predicted with good accuracy overall, and in most cases bS-SDM did not produce a biased prediction exceeding the actual number of species in each unit. In the prediction of community composition bS-SDM often also yielded the best evaluation score. In the case of poor performance of bS-SDM (i.e. when bS-SDM overestimated the prediction of richness) the SESAM framework improved predictions of species composition. Main conclusions Our results differed from previous findings using community-level models. First, we show that overprediction of richness by bS-SDM is not a general rule, thus highlighting the relevance of producing good individual SDMs to capture the ecological filters that are important for the assembly process. Second, we confirm the potential of SESAM when richness is overpredicted by bS-SDM; limiting the number of species for each unit and applying biotic rules (here using the ranking of SDM probabilities) can improve predictions of species composition

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Introduction: Patients with Cystic fibrosis (CF) are more susceptible to pathogens like P. aeruginosa (PA). PA primo-infection requires particular attention as failure in eradication is associated with accelerated lung deterioration. The main aim of this study is to assess the rate of PA eradication according to our particular protocol with inhaled tobramycin and oral ciprofloxacin, as there is no consensus in the literature on what eradication protocol is optimal. Methods: Retrospective single centre study with data analysis from June 1st 2007 to June 1st 2011 of patients with PA primo-infection exclusively treated by 3 x 28 days of inhaled tobramycin and oral ciprofloxacin for the first and last 21 days. Success in eradication is defined by ≥ 3 negative bacteriologies for 6 months after the beginning of the protocol. If ≥ 1 bacteriology is positive, we consider the eradication as a failure. Results: Out of 41 patients, 18 followed the eradication protocol and were included in our analysis (7 girls (38.9%) and 11 boys (61.1%)). Boys had 12 primo-infections and girls had 8. Among these 20 primo-infections, 16 (80%) had an overall success in eradication and 4 (20%) a failure. There was no significant statistical differences in age between these groups (t-test = 0.07, p = 0.94), nor for FEV1% (t-test = 0.96, p = 0.41) or BMI (t-test = 1.35, p = 0.27). Rate of success was 100% for girls and 66.6% for boys. Conclusion: Our protocol succeeded in an overall eradication rate of 80%, without statistical significant impact on FEV1 % and BMI values. However, there was a sex difference with eradication rates in girls (100%) and boys (66.6%). A sex difference has not yet been reported in the literature. This should be evaluated in further studies.

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We report the case of a 53 year old patient who was admitted with polyuria, polydipsia associated with fatigue, depression and sexual dysfunction. Central diabetes insipidus with hypogonadotrophic hypogonadism was diagnosed by a water restriction test and different static and dynamic hormonal dosages. Nodular thickening of the pituitary stalk was noted on the MRI and the biopsy permitted a histological diagnosis of infundibulitis.

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Työ käsittelee tietohallintoa tietointensiivisenä yrityspalveluna Lappeenrannan teknillisessä yliopistossa. Yliopiston tulee keskittyä omaan ydinosaamiseensa sekä erottaa sisäiset yrityspalvelut omiksi kokonaisuuksikseen. Tähän on käytetty tietohallinnon osalta tilaaja tuottajamallia. Mallin puitteissa tietohallintoyksikkö on kattavasti tunnistanut ja määritellyt oman toimintansa sekä asiakkaidensa perustarpeet. Tietohallinnon palvelut ovat tietointensiivisiä yrityspalveluita, joiden tarkoituksena on täydentää asiakkaiden osaamista ja kykyä tuottaa innovaatioita sekä välittää muualla tuotettua tietoa ja teknisiä ratkaisuja tähän tarpeeseen. Tietointensiivisen palveluntuottajan asiantuntijuus on kokemusperäistä ja hiljaista tietoa, jota on lähtökohtaisesti vaikea muuttaa organisatoriseksi tiedoksi eli lisäarvoksi organisaation toiminnalle. Tuotteistamista on hyödynnetty tietohallinnon prosessien muuttamiseksi eksplisiittisiksi. Tuotteistamalla standardoidaan prosesseihin liittyvät parhaat käytänteet, joka tarkoittaa kokemusperäisesti hyväksi havaittujen toimintatapojen rutinoimista. Tuotetut palvelut on tuotteistettu palvelupaketeiksi, joista on laadittu yksityiskohtainen palvelukuvaus sekä laskettu tuotekohtainen hinta. Palvelumallin soveltaminen takaa yksikkökustannusten, skaalaetujen, riskin jakaantumisen ja teknologisen kehityksen optimoinnin yliopistossa.

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In this thesis (TFG) the results of the comparison between different methods to obtain a recombinant protein, by orthologous and heterologous expression, are exposed. This study will help us to identify the best way to express and purify a recombinant protein that will be used for biotechnology applications. In the first part of the project the goal was to find the best expression and purification system to obtain the recombinant protein of interest. To achieve this objective, a system expression in bacteria and in yeast was designed. The DNA was cloned into two different expression vectors to create a fusion protein with two different tags, and the expression of the protein was induced by IPTG or glucose. Additionally, in yeast, two promoters where used to express the protein, the one corresponding to the same protein (orthologous expression), and the ENO2 promoter (heterologous expression). The protein of interest is a NAD-dependent enzyme so, in a second time, its specific activity was evaluated by coenzyme conversion. The results of the TFG suggest that, comparing the model organisms, bacteria are more efficient than yeast because the quantity of protein obtained is higher and better purified. Regarding yeast, comparing the two expression mechanisms that were designed, heterologous expression works much better than the orthologous expression, so in case that we want to use yeast as expression model for the protein of interest, ENO2 will be the best option. Finally, the enzymatic assays, done to compare the effectiveness of the different expression mechanisms respect to the protein activity, revealed that the protein purified in yeast had more activity in converting the NAD coenzyme.