924 resultados para Combined Web crippling and Flange Crushing


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[ES] El Trabajo de Fin de Grado, Monitor Web de Expresiones Regulares (MWRegEx), es una herramienta basada en tecnologías web, desarrollada usando el entorno Visual Studio. El objetivo principal de la aplicación es dar apoyo a la docencia de expresiones regulares, en el marco de la enseñanza del manejo de ristras de caracteres en las asignaturas de programación del Grado en Ingeniería Informática.  La aplicación permite obtener el dibujo de un autómata de una expresión regular, facilitando su comprensión; además, permite aplicar la expresión a diferentes ristras de caracteres, mostrando las coincidencias encontradas, y ofrece una versión de la expresión adaptada a su uso en literales string de lenguajes como Java y otros. La herramienta se ha implementado en dos partes: un servicio web, escrito en C#, donde se realizan todos los análisis de las expresiones regulares y las ristras a contrastar; y un cliente web, implementado usando tecnología asp.net, con JavaScript y JQuery, que gestiona la interfaz de usuario y muestra los resultados. Esta separación permite que el servicio web pueda ser reutilizado con otras aplicaciones cliente. El autómata que representa una expresión regular esta dibujado usando la librería Raphaël JavaScript que permite manejar los elementos SVG. Cada elemento de la expresión regular tiene un dibujo diferente y único para así diferenciarlo. Toda la interfaz gráfica de usuario está internacionalizada de manera tal que pueda adaptarse a diferentes idiomas y regiones sin la necesidad de realizar cambios de ingeniería ni en el código. Tanto el servicio web como la parte cliente están estructurados para que se puedan agregar nuevas modificaciones sin que esto genere una onda expansiva a lo largo de las diversas clases existentes.

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To understand a city and its urban structure it is necessary to study its history. This is feasible through GIS (Geographical Information Systems) and its by-products on the web. Starting from a cartographic view they allow an initial understanding of, and a comparison between, present and past data together with an easy and intuitive access to database information. The research done led to the creation of a GIS for the city of Bologna. It is based on varied data such as historical map, vector and alphanumeric historical data, etc.. After providing information about GIS we thought of spreading and sharing the collected data on the Web after studying two solutions available on the market: Web Mapping and WebGIS. In this study we discuss the stages, beginning with the development of Historical GIS of Bologna, which led to the making of a WebGIS Open Source (MapServer and Chameleon) and the Web Mapping services (Google Earth, Google Maps and OpenLayers).

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Regulatory T cells (Treg) actively regulate alloimmune responses and promote transplantation tolerance. Polyclonal anti-thymocyte globulin (ATG), a widely used induction therapy in clinical organ transplantation, depletes peripheral T cells. However, resistance to tolerance induction is seen with certain T cell depleting strategies and is attributed to alterations in the balance of naïve, memory and regulatory T cells. Here we report a novel reagent, murine ATG (mATG), depletes T cells but preferentially spares CD25+ natural Tregs which limit skewing of T cell repertoire toward T-effector-memory (Tem) phenotype among the recovering T cells. T-cell depletion with mATG combined with CTLA4Ig and Sirolimus synergize to prolong graft survival by tipping the Treg/Tem balance further in favor of Tregs by preserving Tregs, facilitating generation of new Tregs by a conversion mechanism and limiting Tem expansion in response to alloantigen and homeostatic proliferation. These results provide the rationale for translating such novel combination therapies to promote tolerance in primate and human organ transplantation.

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The Ph.D. thesis deals with the conformational study of individual cylindrical polymer brush molecules using atomic force microscopy (AFM). Imaging combined with single molecule manipulation has been used to unravel questions concerning conformational changes, desorption behavior and mechanical properties of individual macromolecules and supramolecular structures. In the first part of the thesis (chapter 5) molecular conformations of cylindrical polymer brushes with poly-(N-isopropylacrylamide) (PNIPAM) side chains were studied in various environmental conditions. Also micelle formation of cylindrical brush-coil blockcopolymers with polyacrylic acid side chains and polystyrene coil have been visualized. In chapter 6 the mechanical properties of single cylindrical polymer brushes with (PNIPAM) side chains were investigated. Assuming that the brushes adopt equilibrium conformation on the surface, an average persistence length of lp= (29 ± 3) nm was determined by the end-to-end distance vs. contour length analysis in terms of the wormlike chain (WLC) model. Stretching experiments suggest that an exact determination of the persistence length using force extension curves is impeded by the contribution of the side chains. Modeling the stretching of the bottle brush molecule as extension of a dual spring (side chain and main chain) explains the frequently observed very low persistence length arising from a dominant contribution of the side chain elasticity at small overall contour lengths. It has been shown that it is possible to estimate the “true” persistence length of the bottle brush molecule from the intercept of a linear extrapolation of the inverse square root of the apparent persistence length vs. the inverse contour length plot. By virtue of this procedure a “true” persistence length of 140 nm for the PNIPAM brush molecules is predicted. Chapter 7 and 8 deal with the force-extension behavior of PNIPAM cylindrical brushes studied in poor solvent conditions. The behavior is shown to be qualitatively different from that in a good solvent. Force induced globule-cylinder conformational changes are monitored using “molecule specific force spectroscopy” which is a combined AFM imaging and SMFS technique. An interesting behavior of the unfolding-folding transitions of single collapsed PNIPAM brush molecules has been observed by force spectroscopy using the so called “fly-fishing” mode. A plateau force is observed upon unfolding the collapsed molecule, which is attributed to a phase transition from a collapsed brush to a stretched conformation. Chapter 9 describes the desorption behavior of single cylindrical polyelectrolyte brushes with poly-L-lysine side chains deposited on a mica surface using the “molecule specific force spectroscopy” technique to resolve statistical discrepancies usually observed in SMFS experiments. Imaging of the brushes and inferring the persistence length from a end-to-end distance vs. contour length analysis results in an average persistence length of lp = (25 ± 5) nm assuming that the chains adopt their equilibrium conformation on the surface. Stretching experiments carried out on individual poly-L-lysine brush molecules by force spectroscopy using the “fly-fishing” mode provide a persistence length in the range of 7-23 nm in reasonable accordance with the imaging results. In chapter 10 the conformational behavior of cylindrical poly-L-lysine brush-sodium dodecyl sulfate complexes was studied using AFM imaging. Surfactant induced cylinder to helix like to globule conformational transitions were observed.

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The present issue analyses bluefin tuna (Thynnus thunnus) and swordfish (Xiphias glaudis) diet, caught by professional long-line fishing in the middle Adriatic Sea (Pomo pit). These species represent apex predators in pelagic environment that may play key roles in determining food web structure and ecosystem dynamics. The studies about their feedings habits, based upon stomach contents analysis, are important for the comprehension of biological and ecological interaction. Over the years, many studies have been performed on the diet of tuna and swordfish in the Mediterranean Sea. This research is based on a fairly wide number of analyzed stomach contents, in comparison with the previous ones. In this work, the analysis of 340 stomach contents of bluefin tuna caught by long-line in the central Adriatic sea confirms in general the opportunistic behaviour of this species. Finding support the hypothesis that Adriatic tuna and swordfish chase their food over a wide bathymetric zone and probably near the surface at night. No indication of food preference respect to size of predator or sample season are found. It seems that the two species are able to cohabit because their trophic niche are not overlapped, changing during the time and the vertical and horizontal space.

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Over the past years fruit and vegetable industry has become interested in the application of both osmotic dehydration and vacuum impregnation as mild technologies because of their low temperature and energy requirements. Osmotic dehydration is a partial dewatering process by immersion of cellular tissue in hypertonic solution. The diffusion of water from the vegetable tissue to the solution is usually accompanied by the simultaneous solutes counter-diffusion into the tissue. Vacuum impregnation is a unit operation in which porous products are immersed in a solution and subjected to a two-steps pressure change. The first step (vacuum increase) consists of the reduction of the pressure in a solid-liquid system and the gas in the product pores is expanded, partially flowing out. When the atmospheric pressure is restored (second step), the residual gas in the pores compresses and the external liquid flows into the pores. This unit operation allows introducing specific solutes in the tissue, e.g. antioxidants, pH regulators, preservatives, cryoprotectancts. Fruit and vegetable interact dynamically with the environment and the present study attempts to enhance our understanding on the structural, physico-chemical and metabolic changes of plant tissues upon the application of technological processes (osmotic dehydration and vacuum impregnation), by following a multianalytical approach. Macro (low-frequency nuclear magnetic resonance), micro (light microscopy) and ultrastructural (transmission electron microscopy) measurements combined with textural and differential scanning calorimetry analysis allowed evaluating the effects of individual osmotic dehydration or vacuum impregnation processes on (i) the interaction between air and liquid in real plant tissues, (ii) the plant tissue water state and (iii) the cell compartments. Isothermal calorimetry, respiration and photosynthesis determinations led to investigate the metabolic changes upon the application of osmotic dehydration or vacuum impregnation. The proposed multianalytical approach should enable both better designs of processing technologies and estimations of their effects on tissue.

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Salmonella and Campylobacter are common causes of human gastroenteritis. Their epidemiology is complex and a multi-tiered approach to control is needed, taking into account the different reservoirs, pathways and risk factors. In this thesis, trends in human gastroenteritis and food-borne outbreak notifications in Italy were explored. Moreover, the improved sensitivity of two recently-implemented regional surveillance systems in Lombardy and Piedmont was evidenced, providing a basis for improving notification at the national level. Trends in human Salmonella serovars were explored: serovars Enteritidis and Infantis decreased, Typhimurium remained stable and 4,[5],12:i:-, Derby and Napoli increased, suggesting that sources of infection have changed over time. Attribution analysis identified pigs as the main source of human salmonellosis in Italy, accounting for 43–60% of infections, followed by Gallus gallus (18–34%). Attributions to pigs and Gallus gallus showed increasing and decreasing trends, respectively. Potential bias and sampling issues related to the use of non-local/non-recent multilocus sequence typing (MLST) data in Campylobacter jejuni/coli source attribution using the Asymmetric Island (AI) model were investigated. As MLST data become increasingly dissimilar with increasing geographical/temporal distance, attributions to sources not sampled close to human cases can be underestimated. A combined case-control and source attribution analysis was developed to investigate risk factors for human Campylobacter jejuni/coli infection of chicken, ruminant, environmental, pet and exotic origin in The Netherlands. Most infections (~87%) were attributed to chicken and cattle. Individuals infected from different reservoirs had different associated risk factors: chicken consumption increased the risk for chicken-attributed infections; animal contact, barbecuing, tripe consumption, and never/seldom chicken consumption increased that for ruminant-attributed infections; game consumption and attending swimming pools increased that for environment-attributed infections; and dog ownership increased that for environment- and pet-attributed infections. Person-to-person contacts around holiday periods were risk factors for infections with exotic strains, putatively introduced by returning travellers.

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Die vorliegende Dissertation behandelt die Gesamtgesteinsanalyse stabiler Siliziumisotope mit Hilfe einer „Multi Collector-ICP-MS“. Die Analysen fanden in Kooperation mit dem „Royal Museum for Central Africa“ in Belgien statt. Einer der Schwerpunkte des ersten Kapitels ist die erstmalige Analyse des δ30Si –Wertes an einem konventionellen Nu PlasmaTM „Multi-Collector ICP-MS“ Instrument, durch die Eliminierung der den 30Si “peak” überlagernden 14N16O Interferenz. Die Analyse von δ30Si wurde durch technische Modifikationen der Anlage erreicht, welche eine höherer Massenauflösung ermöglichten. Die sorgsame Charakterisierung eines adäquaten Referenzmaterials ist unabdingbar für die Abschätzung der Genauigkeit einer Messung. Die Bestimmung der „U.S. Geological Survey“ Referenzmaterialien bildet den zweiten Schwerpunkt dieses Kapitales. Die Analyse zweier hawaiianischer Standards (BHVO-1 and BHVO-2), belegt die präzise und genaue δ30Si Bestimmung und bietet Vergleichsdaten als Qualitätskontrolle für andere Labore. Das zweite Kapitel befasst sich mit kombinierter Silizium-/Sauerstoffisotope zur Untersuchung der Entstehung der Silizifizierung vulkanischer Gesteine des „Barberton Greenstone Belt“, Südafrika. Im Gegensatz zu heute, war die Silizifizierung der Oberflächennahen Schichten, einschließlich der „Chert“ Bildung, weitverbreitete Prozesse am präkambrischen Ozeanboden. Diese Horizonte sind Zeugen einer extremen Siliziummobilisierung in der Frühzeit der Erde. Dieses Kapitel behandelt die Analyse von Silizium- und Sauerstoffisotopen an drei unterschiedlichen Gesteinsprofilen mit unterschiedlich stark silizifizierten Basalten und überlagernden geschichteten „Cherts“ der 3.54, 3.45 und 3.33 Mill. Jr. alten Theespruit, Kromberg und Hooggenoeg Formationen. Siliziumisotope, Sauerstoffisotope und die SiO2-Gehalte demonstrieren in allen drei Gesteinsprofilen eine positive Korrelation mit dem Silizifizierungsgrad, jedoch mit unterschiedlichen Steigungen der δ30Si-δ18O-Verhältnisse. Meerwasser wird als Quelle des Siliziums für den Silizifizierungsprozess betrachtet. Berechnungen haben gezeigt, dass eine klassische Wasser-Gestein Wechselwirkung die Siliziumisotopenvariation nicht beeinflussen kann, da die Konzentration von Si im Meerwasser zu gering ist (49 ppm). Die Daten stimmen mit einer Zwei-Endglieder-Komponentenmischung überein, mit Basalt und „Chert“ als jeweilige Endglieder. Unsere gegenwärtigen Daten an den „Cherts“ bestätigen einen Anstieg der Isotopenzusammensetzung über der Zeit. Mögliche Faktoren, die für unterschiedliche Steigungen der δ30Si-δ18O Verhältnisse verantwortlich sein könnten sind Veränderungen in der Meerwasserisotopie, der Wassertemperatur oder sekundäre Alterationseffekte. Das letzte Kapitel beinhaltet potentielle Variationen in der Quellregion archaischer Granitoide: die Si-Isotopen Perspektive. Natriumhaltige Tonalit-Trondhjemit-Granodiorit (TTG) Intrusiva repräsentieren große Anteile der archaischen Kruste. Im Gegensatz dazu ist die heutige Kruste kaliumhaltiger (GMS-Gruppe: Granit-Monzonite-Syenite). Prozesse, die zu dem Wechsel von natriumhaltiger zu kaliumhaltiger Kruste führten sind die Thematik diesen Kapitels. Siliziumisotopenmessungen wurden hier kombiniert mit Haupt- und Spurenelementanalysen an unterschiedlichen Generationen der 3.55 bis 3.10 Mill. Yr. alten TTG und GMS Intrusiva aus dem Arbeitsgebiet. Die δ30Si-Werte in den unterschiedlichen Plutonit Generationen zeigen einen leichten Anstieg der Isotopie mit der Zeit, wobei natriumhaltige Intrusiva die niedrigste Si-Isotopenzusammensetzung aufweisen. Der leichte Anstieg in der Siliziumisotopenzusammensetzung über die Zeit könnte auf unterschiedliche Temperaturbedingungen in der Quellregion der Granitoide hinweisen. Die Entstehung von Na-reichen, leichten d30Si Granitoiden würde demnach bei höheren Temperaturen erfolgen. Die Ähnlichkeit der δ30Si-Werte in archaischen K-reichen Plutoniten und phanerozoischen K-reichen Plutoniten wird ebenfalls deutlich.

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In this thesis the evolution of the techno-social systems analysis methods will be reported, through the explanation of the various research experience directly faced. The first case presented is a research based on data mining of a dataset of words association named Human Brain Cloud: validation will be faced and, also through a non-trivial modeling, a better understanding of language properties will be presented. Then, a real complex system experiment will be introduced: the WideNoise experiment in the context of the EveryAware european project. The project and the experiment course will be illustrated and data analysis will be displayed. Then the Experimental Tribe platform for social computation will be introduced . It has been conceived to help researchers in the implementation of web experiments, and aims also to catalyze the cumulative growth of experimental methodologies and the standardization of tools cited above. In the last part, three other research experience which already took place on the Experimental Tribe platform will be discussed in detail, from the design of the experiment to the analysis of the results and, eventually, to the modeling of the systems involved. The experiments are: CityRace, about the measurement of human traffic-facing strategies; laPENSOcosì, aiming to unveil the political opinion structure; AirProbe, implemented again in the EveryAware project framework, which consisted in monitoring air quality opinion shift of a community informed about local air pollution. At the end, the evolution of the technosocial systems investigation methods shall emerge together with the opportunities and the threats offered by this new scientific path.

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Die im Süden der Türkei gelegen, antiken Städte Aspendos und Patara, waren in der Römerzeit zwei bedeutende Handelszentren mit hoher Bevölkerungsdichte. Aquädukte versorgten beide Städte mit carbonathaltigem Wasser, wobei sich Kalksinter (Calciumcarbonat) in der Kanalrinne ablagerte. Dabei lagern sich im Wechsel eine hellere und dunklere Kalksinterlage ab, die als Sinterpaar bezeichnet wird. Um die Entstehung dieser Sinterpaare besser zu verstehen, und die beteiligten Prozesse mit saisonalen Veränderungen der Umwelt zu korrelieren, werden in der vorliegenden Arbeit laminierten Sinterablagerungen mit geochemischen und petrographischen Methoden untersucht.rnEntlang der Kanalrinne beider Aquädukte wurden an mehreren Stellen Proben entnommen. Es wurde untersucht in wieweit sich die Sinterstruktur aufgrund von Änderungen in der Neigung des Wasserkanals oder des Kanaltyps ändert. Um die Kristallform und die kristallografische Orientierung der Kristalle innerhalb der verschiedenen Sinterpaare zu untersuchen, wurden die entnommenen laminierten Kalksinterablagerungen mit Hilfe optischer Mikroskopie und EBSD (Electron Backscatter Diffraction) analysiert. Der Electron Probe Micro-Analyzer (EPMA) wurde verwendet, um saisonale Schwankungen der Hauptelementverteilung und den Anteil der stabilen Isotope im Wasser zu bestimmen. Die LA-ICP-MS (Laser Ablation-induktiv gekoppeltem Plasma-Massenspektrometrie) Spurenelementanalyse wurde durchgeführt, um kleinste Schwankungen der Spurenelemente zu finden. Basierend auf diesen Analysen wurde festgestellt, dass laminierten Kalksinterablagerungen laterale Änderungen in der Aquäduktstruktur und -neigung, jahreszeitliche Änderungen der Wasserchemie, der Temperatur sowie der Entgasungsrate während eines Jahres widerspiegeln. Die Kalksinterablagerungen zeigen eine deutliche Laminierung in Form von feinkörnig-porösen und grobkörnig-dichten Schichten, die trockene und nasse Jahreszeiten anzeigen. Feinkörnige Schichten zeigen eine hohe Epifluoreszenz aufgrund reichhaltiger organischer Inhalte, die vermutlich eine Folge der bakteriellen Aktivität während der warmen und trockenen Jahreszeit sind. Stabile Sauerstoff und Kohlenstoff-Isotop-Kurven entsprechen auch den jahreszeitlichen Schwankungen der verschiedenen Schichtenpaare. Vor allem δ 18O spiegelt jährliche Veränderungen in der Temperatur und jahreszeitliche Veränderungen des Abflusses wieder. Das wichtigste Ergebnis ist, dass die Periodizität von δ 18O durch Erwärmen des Wassers im Wasserkanal und nicht durch die Verdunstung oder der Brunnenwasser-Charakteristik verursacht wird. Die Periodizität von δ 13C ist komplexer Natur, vor allem zeigen δ 18O und δ 13C eine Antikorrelation entlang der Lamellenpaare. Dies wird wohl vor allem durch Entgasungsprozesse im Aquädukt verursacht. Die Ergebnisse der Spurenelemente sind meist inkonsistent und zeigen keine signifikanten Veränderungen in den verschiedenen Lamellenpaaren. Die Isotope Mg, Sr und Ba zeigen hingegen bei einigen Proben eine positive Korrelation und erreichen Höchstwerte innerhalb feinkörnig-poröser Schichten. Auch sind die Hauptelementwerte von Fe, K, Si und anderer detritischer Elemente innerhalb der feinkörnige-porösen Schichten maximal. Eine genaue Datierung der Kalksinterablagerungen ist wünschenswert, da der Zeitraum, in dem die Aquädukte aktiv waren, bereits archäologisch auf 200-300 Jahre festgelegt wurde. Paläomagnetische und 14C-Datierung geben keine brauchbare Ergebnisse. Die U/Th Isotopie wird durch eine hohe Anfangskonzentration von Th in den Proben behindert. Trotz dieser Schwierigkeiten war eine U/Th Datierung an einem Testbeispiel des Béziers Aquädukt erfolgreich. Mit Hilfe von analogen Untersuchungen an aktiven Wasserkanälen der heutigen Zeit, werden die Ablagerungsmechanismen und die geochemische Entwicklung der laminierten Sinterschichten besser verstanden. Ein weiteres laufendes Projekt dieser Doktorarbeit ist die Überwachung von Sinterabscheidungen und der saisonale Zusammensetzung des Wassers an einigen heute noch aktiven Aquädukten. Das Ziel ist die Untersuchung der jetzigen Calciumcarbonatabscheidungen in Aquäduktkanälen unter den heutigen Umgebungsbedingungen. Erste Ergebnisse zeigen, dass kleine regelmäßige jahreszeitliche Veränderungen in der Isotopenzusammensetzung des Wassers vorliegen, und dass die beobachtete Periodizität der stabilen Isotope aufgrund von Änderungen im eigentlichen Kanal entstanden ist. Die Untersuchung von Kalksinterablagerungen in römischen Aquädukten liefern vielversprechende Ergebnisse, für die Untersuchung des Paläöklimas, der Archaeoseismologie und anderer Umweltbedingungen in der Römerzeit. Diese Studie beschränkt sich auf zwei Aquädukte. Die Untersuchungen weiterer Aquädukte und einer Überwachung, der noch in Betrieb stehenden Aquädukte werden genauere Ergebnisse liefern.

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Ein Tag ohne Internet ist für viele kaum vorstellbar. Das Spektrum der Internetnutzer ist breiter geworden und damit sind die Ansprüche an die Websites massiv angestiegen. Die Entscheidung auf einer Website zu bleiben oder auf einer anderen zu suchen fällt innerhalb von wenigen Sekunden. Diese Entscheidung ist sowohl vom Website-Design als auch von dem dargestellten Inhalt abhängig. Die Auswertung, wie schnell der Benutzer Online-Informationen finden und wie einfach er sie verstehen kann, ist die Aufgabe von Web-Usability-Testing. Für das Finden und Verstehen von Informationen sind die computertechnischen zusammen mit den linguistischen Aspekten zuständig. In der Usability-Forschung liegt jedoch der Fokus bislang weitgehend auf der Bewertung der computer¬linguistischen und ästhetischen Aspekte der Websites. In den Hintergrund gedrängt wurden dabei die linguistischen Aspekte. Im Vergleich sind diese weniger systematisch erforscht und in Usability-Richtlinien kaum zu finden. Stattdessen stößt man überwiegend auf allgemeine Empfehlungen. Motiviert davon hat die vorliegende Arbeit das Ziel, Die Web-Usability systematisch sowohl aus linguistischer als auch aus formaler Sicht zu erforschen. Auf linguistischer Ebene wurde in Anlehnung an die Zeichentheorie von Morris die Web-Usability analysiert und der Begriff Linguistische Web-Usability eingeführt. Auf Basis dieser Analyse sowie einer literaturstudie ‘literature review’ mehrerer Usability-Richtlinien wurde ein Kriterienkatalog entwickelt. Bei der Umsetzung dieses Kriterienkatalogs im Rahmen einer Usability-Studie wurde die Website der Universität Johannes Gutenberg-Universität Mainz (JGU) im Usability-Labor unter Anwendung der Methode Eye-Tracking zusammen mit der Think-Aloud-Methode und der Retrospective-Think-Aloud-Methode getestet. Die empirischen Ergebnisse zeigen, dass die linguistischen Usability-Probleme genau wie die formalen die Benutzer hindern, die gesuchten Informationen zu finden, oder zumindest ihre Suche verlangsamen. Dementsprechend sollten die linguistischen Perspektiven in die Usability-Richtlinien miteinbezogen werden.

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A previous study identified the peroxisome proliferator-activated receptor alpha (PPARalpha) activation biomarkers 21-steroid carboxylic acids 11beta-hydroxy-3,20-dioxopregn-4-en-21-oic acid (HDOPA) and 11beta,20-dihydroxy-3-oxo-pregn-4-en-21-oic acid (DHOPA). In the present study, the molecular mechanism and the metabolic pathway of their production were determined. The PPARalpha-specific time-dependent increases in HDOPA and 20alpha-DHOPA paralleled the development of adrenal cortex hyperplasia, hypercortisolism, and spleen atrophy, which was attenuated in adrenalectomized mice. Wy-14,643 activation of PPARalpha induced hepatic FGF21, which caused increased neuropeptide Y and agouti-related protein mRNAs in the hypothalamus, stimulation of the agouti-related protein/neuropeptide Y neurons, and activation of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in increased adrenal cortex hyperplasia and corticosterone production, revealing a link between PPARalpha and the HPA axis in controlling energy homeostasis and immune regulation. Corticosterone was demonstrated as the precursor of 21-carboxylic acids both in vivo and in vitro. Under PPARalpha activation, the classic reductive metabolic pathway of corticosterone was suppressed, whereas an alternative oxidative pathway was uncovered that leads to the sequential oxidation on carbon 21 resulting in HDOPA. The latter was then reduced to the end product 20alpha-DHOPA. Hepatic cytochromes P450, aldehyde dehydrogenase (ALDH3A2), and 21-hydroxysteroid dehydrogenase (AKR1C18) were found to be involved in this pathway. Activation of PPARalpha resulted in the induction of Aldh3a2 and Akr1c18, both of which were confirmed as target genes through introduction of promoter luciferase reporter constructs into mouse livers in vivo. This study underscores the power of mass spectrometry-based metabolomics combined with genomic and physiologic analyses in identifying downstream metabolic biomarkers and the corresponding upstream molecular mechanisms.

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PURPOSE: The advent of imaging software programs has proved to be useful for diagnosis, treatment planning, and outcome measurement, but precision of 3-dimensional (3D) surgical simulation still needs to be tested. This study was conducted to determine whether the virtual surgery performed on 3D models constructed from cone-beam computed tomography (CBCT) can correctly simulate the actual surgical outcome and to validate the ability of this emerging technology to recreate the orthognathic surgery hard tissue movements in 3 translational and 3 rotational planes of space. MATERIALS AND METHODS: Construction of pre- and postsurgery 3D models from CBCTs of 14 patients who had combined maxillary advancement and mandibular setback surgery and 6 patients who had 1-piece maxillary advancement surgery was performed. The postsurgery and virtually simulated surgery 3D models were registered at the cranial base to quantify differences between simulated and actual surgery models. Hotelling t tests were used to assess the differences between simulated and actual surgical outcomes. RESULTS: For all anatomic regions of interest, there was no statistically significant difference between the simulated and the actual surgical models. The right lateral ramus was the only region that showed a statistically significant, but small difference when comparing 2- and 1-jaw surgeries. CONCLUSIONS: Virtual surgical methods were reliably reproduced. Oral surgery residents could benefit from virtual surgical training. Computer simulation has the potential to increase predictability in the operating room.

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Objective Femoroacetabular impingement may be a risk factor for hip osteoarthritis in men. An underlying hip deformity of the cam type is common in asymptomatic men with nondysplastic hips. This study was undertaken to examine whether hip deformities of the cam type are associated with signs of hip abnormality, including labral lesions and articular cartilage damage, detectable on magnetic resonance imaging (MRI). Methods In this cross-sectional, population-based study in asymptomatic young men, 1,080 subjects underwent clinical examination and completed a self-report questionnaire. Of these subjects, 244 asymptomatic men with a mean age of 19.9 years underwent MRI. All MRIs were read for cam-type deformities, labral lesions, cartilage thickness, and impingement pits. The relationship between cam-type deformities and signs of joint damage were examined using logistic regression models adjusted for age and body mass index. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined. Results Sixty-seven definite cam-type deformities were detected. These deformities were associated with labral lesions (adjusted OR 2.77 [95% CI 1.31, 5.87]), impingement pits (adjusted OR 2.9 [95% CI 1.43, 5.93]), and labral deformities (adjusted OR 2.45 [95% CI 1.06, 5.66]). The adjusted mean difference in combined anterosuperior femoral and acetabular cartilage thickness was −0.19 mm (95% CI −0.41, 0.02) lower in those with cam-type deformities compared to those without. Conclusion Our findings indicate that the presence of a cam-type deformity is associated with MRI-detected hip damage in asymptomatic young men.

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Combined extended nerve and soft tissue defects of the upper extremity require nerve reconstruction and adequate soft tissue coverage. This study focuses on the reliability of the free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap within this indication. An anatomical study was performed on 26 cadaveric lower extremities that had been Thiel fixated and color silicone injected. Dissection of the fasciocutaneous posterior calf flap involved the medial sural nerve and superficial sural artery (SSA) with its septocutaneous perforators, extended laterally to include the lateral cutaneous branch of the sural nerve and continued to the popliteal origin of the vascular pedicle and the nerves. The vessel and nerves diameter were measured with an eyepiece reticle at 4.5× magnification. Length and diameter of the nerves and vessels were carefully assessed and reported in the dissection book. A total of 26 flaps were dissected. The SSA originated from the medial sural artery (13 cases), the popliteal artery (12 cases), or the lateral sural artery (one case). The average size of the SSA was 1.4 ± 0.4 mm. The mean pedicle length before the artery joined the sural nerve was 4.5 ± 1.9 cm. A comitant vein was present in 21 cases with an average diameter of 2.0 ± 0.8 mm, in 5 cases a separate vein needed to be dissected with an average diameter of 3.5 ± 0.4 mm. The mean medial vascularized sural nerve length was 21.2 ± 8.9 cm. Because of inclusion of the vascularized part of the lateral branch of the sural nerve (mean length of 16.7 ± 4.8 cm), a total of 35.0 ± 9.6 cm mean length of vascularized nerve could be gained from each extremity. The free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap pedicled on the SSA offers a reliable solution for complex tissue and nerve defect. Clin. Anat. 2012. © 2012 Wiley Periodicals, Inc.