854 resultados para Concept-based Retrieval


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A novel approach for the identification of tumor antigen-derived sequences recognized by CD8(+) cytolytic T lymphocytes (CTL) consists in using synthetic combinatorial peptide libraries. Here we have screened a library composed of 3.1 x 10(11) nonapeptides arranged in a positional scanning format, in a cytotoxicity assay, to search the antigen recognized by melanoma-reactive CTL of unknown specificity. The results of this analysis enabled the identification of several optimal peptide ligands, as most of the individual nonapeptides deduced from the primary screening were efficiently recognized by the CTL. The results of the library screening were also analyzed with a mathematical approach based on a model of independent and additive contribution of individual amino acids to antigen recognition. This biometrical data analysis enabled the retrieval, in public databases, of the native antigenic peptide SSX-2(41-49), whose sequence is highly homologous to the ones deduced from the library screening, among the ones with the highest stimulatory score. These results underline the high predictive value of positional scanning synthetic combinatorial peptide library analysis and encourage its use for the identification of CTL ligands.

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This study proposes a new concept for upscaling local information on failure surfaces derived from geophysical data, in order to develop the spatial information and quickly estimate the magnitude and intensity of a landslide. A new vision of seismic interpretation on landslides is also demonstrated by taking into account basic geomorphic information with a numeric method based on the Sloping Local Base Level (SLBL). The SLBL is a generalization of the base level defined in geomorphology applied to landslides, and allows the calculation of the potential geometry of the landslide failure surface. This approach was applied to a large scale landslide formed mainly in gypsum and situated in a former glacial valley along the Rhone within the Western European Alps. Previous studies identified the existence of two sliding surfaces that may continue below the level of the valley. In this study. seismic refraction-reflexion surveys were carried out to verify the existence of these failure surfaces. The analysis of the seismic data provides a four-layer model where three velocity layers (<1000 ms(-1), 1500 ms(-1) and 3000 ms(-1)) are interpreted as the mobilized mass at different weathering levels and compaction. The highest velocity layer (>4000 ms(-1)) with a maximum depth of similar to 58 m is interpreted as the stable anhydrite bedrock. Two failure surfaces were interpreted from the seismic surveys: an upper failure and a much deeper one (respectively 25 and 50 m deep). The upper failure surface depth deduced from geophysics is slightly different from the results obtained using the SLBL, and the deeper failure surface depth calculated with the SLBL method is underestimated in comparison with the geophysical interpretations. Optimal results were therefore obtained by including the seismic data in the SLBL calculations according to the geomorphic limits of the landslide (maximal volume of mobilized mass = 7.5 x 10(6) m(3)).

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The National Academies has stressed the need to develop quantifiable measures for methods that are currently qualitative in nature, such as the examination of fingerprints. Current protocols and procedures to perform these examinations rely heavily on a succession of subjective decisions, from the initial acceptance of evidence for probative value to the final assessment of forensic results. This project studied the concept of sufficiency associated with the decisions made by latent print examiners at the end of the various phases of the examination process. During this 2-year effort, a web‐based interface was designed to capture the observations of 146 latent print examiners and trainees on 15 pairs of latent/control prints. Two main findings resulted from the study: The concept of sufficiency is driven mainly by the number and spatial relationships between the minutiae observed on the latent and control prints. Data indicate that demographics (training, certification, years of experience) or non‐minutiae based features (such as level 3 features) do not play a major role in examiners' decisions; Significant variability was observed between detecting and interpreting friction ridge features and at all levels of details, as well as for factors that have the potential to influence the examination process, such as degradation, distortion, or influence of the background and the development technique.

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Dual mobility cup systems in total hip arthroplasty consist of a metal back with a non-constrained liner, in which a constrained standard head articulates. While superior stability of such implants in comparison with standard total hip replacements is assumed, it is the purpose of this study to outline the biomechanical concept of dual mobility cups and to describe implant survival and dislocation rate based on the series published in the English-speaking and Francophone literature. A growing body of evidence indicates reduced dislocation rates in primary and revision total hip arthroplasty and in selected tumour cases. The limited availability of studies evaluating long-term implant survival and existing concerns with regard to increased wear rates and aseptic loosening, leads to the conclusion that such implants have to be used with prudence, particularly in standard primary hip arthroplasty and in young patients.

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This project continues the research which addresses the numerous bridge problems on the Iowa secondary road system. It is a continuation (Phase 2) of Project HR-382, in which two replacement alternatives (Concept 1: Steel Beam Precast Units and Concept 2: Modification of the Benton County Beam-in-Slab Bridge) were investigated. In previous research for concept 1, a precast unit bridge was developed through laboratory testing. The steel-beam precast unit bridge requires the fabrication of precast double-tee (PCDT) units, each consisting of two steel beams connected by a reinforced concrete deck. The weight of each PCDT unit is minimized by limiting the deck thickness to 4 in., which permits the units to be constructed off-site and then transported to the bridge site. The number of units required is a function of the width of bridge desired. Once the PCDT units are connected, a cast-in-place reinforced concrete deck is cast over the PCDT units and the bridge railing attached. Since the steel beam PCDT unit bridge design is intended primarily for use on low-volume roads, used steel beams can be utilized for a significant cost savings. In previous research for concept 2, an alternate shear connector (ASC) was developed and subjected to static loading. In this investigation, the ASC was subjected to cyclic loading in both pushout specimens and composite beam tests. Based on these tests, the fatigue strength of the ASC was determined to be significantly greater than that required in typical low volume road single span bridges. Based upon the construction and service load testing, the steel-beam precast unit bridge was successfully shown to be a viable low volume road bridge alternative. The construction process utilized standard methods resulting in a simple system that can be completed with a limited staff. Results from the service load tests indicated adequate strength for all legal loads. An inspection of the bridge one year after its construction revealed no change in the bridge's performance. Each of the systems previously described are relatively easy to construct. Use of the ASC rather than the welded studs significantly simplified the work, equipment, and materials required to develop composite action between the steel beams and the concrete deck.

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Context:  Until now, the testosterone/epitestosterone (T/E) ratio is the main marker for detection of testosterone (T) misuse in athletes. As this marker can be influenced by a number of confounding factors, additional steroid profile parameters indicating T misuse can provide substantiating evidence of doping with endogenous steroids. The evaluation of a steroid profile is currently based upon population statistics. Since large inter-individual variations exist, a paradigm shift towards subject-based references is ongoing in doping analysis. Objective:  Proposition of new biomarkers for the detection of testosterone in sports using extensive steroid profiling and an adaptive model based upon Bayesian inference. Subjects:  6 healthy male volunteers were administered with testosterone undecanoate. Population statistics were performed upon steroid profiles from 2014 male Caucasian athletes participating in official sport competition. Design:  An extended search for new biomarkers in a comprehensive steroid profile combined with Bayesian inference techniques as used in the Athlete Biological Passport resulted in a selection of additional biomarkers that may improve detection of testosterone misuse in sports. Results:  Apart from T/E, 4 other steroid ratios (6α-OH-androstenedione/16α-OH-dehydroepiandrostenedione, 4-OH-androstenedione/16α-OH-androstenedione, 7α-OH-testosterone/7β-OH-dehydroepiandrostenedione and dihydrotestosterone/5β-androstane-3α,17β-diol) were identified as sensitive urinary biomarkers for T misuse. These new biomarkers were rated according to relative response, parameter stability, detection time and discriminative power. Conclusion:  Newly selected biomarkers were found suitable for individual referencing within the concept of the Athlete's Biological Passport. The parameters showed improved detection time and discriminative power compared to the T/E ratio. Such biomarkers can support the evidence of doping with small oral doses of testosterone.

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This project continues the research which addresses the numerous bridge problems on the Iowa secondary road system. It is a continuation (Phase 2) of Project HR-382, in which two replacement alternatives (Concept 1: Steel Beam Precast Units and Concept 2: Modification of the Benton County Beam-in-Slab Bridge) were investigated. In previous research for concept 1, a precast unit bridge was developed through laboratory testing. The steel-beam precast unit bridge requires the fabrication of precast double-tee (PCDT) units, each consisting of two steel beams connected by a reinforced concrete deck. The weight of each PCDT unit is minimized by limiting the deck thickness to 4 in., which permits the units to be constructed off-site and then transported to the bridge site. The number of units required is a function of the width of bridge desired. Once the PCDT units are connected, a cast-in-place reinforced concrete deck is cast over the PCDT units and the bridge railing attached. Since the steel beam PCDT unit bridge design is intended primarily for use on low-volume roads, used steel beams can be utilized for a significant cost savings. In previous research for concept 2, an alternate shear connector (ASC) was developed and subjected to static loading. In this investigation, the ASC was subjected to cyclic loading in both pushout specimens and composite beam tests. Based on these tests, the fatigue strength of the ASC was determined to be significantly greater than that required in typical low volume road single span bridges. Based upon the construction and service load testing, the steel-beam precast unit bridge was successfully shown to be a viable low volume road bridge alternative. The construction process utilized standard methods resulting in a simple system that can be completed with a limited staff. Results from the service load tests indicated adequate strength for all legal loads. An inspection of the bridge one year after its construction revealed no change in the bridge's performance. Each of the systems previously described are relatively easy to construct. Use of the ASC rather than the welded studs significantly simplified the work, equipment, and materials required to develop composite action between the steel beams and the concrete deck.

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This research was conducted in the context of the project IRIS 8A Health and Society (2002-2008) and financially supported by the University of Lausanne. It was aomed at developping a model based on the elder people's experience and allowed us to develop a "Portrait evaluation" of fear of falling using their examples and words. It is a very simple evaluation, which can be used by professionals, but by the elder people themselves. The "Portrait evaluation" and the user's guide are on free access, but we would very much approciate to know whether other people or scientists have used it and collect their comments. (contact: Chantal.Piot-Ziegler@unil.ch)The purpose of this study is to create a model grounded in the elderly people's experience allowing the development of an original instrument to evaluate FOF.In a previous study, 58 semi-structured interviews were conducted with community-dwelling elderly people. The qualitative thematic analysis showed that fear of falling was defined through the functional, social and psychological long-term consequences of falls (Piot-Ziegler et al., 2007).In order to reveal patterns in the expression of fear of falling, an original qualitative thematic pattern analysis (QUAlitative Pattern Analysis - QUAPA) is developed and applied on these interviews.The results of this analysis show an internal coherence across the three dimensions (functional, social and psychological). Four different patterns are found, corresponding to four degrees of fear of falling. They are formalized in a fear of falling intensity model.This model leads to a portrait-evaluation for fallers and non-fallers. The evaluation must be confronted to large samples of elderly people, living in different environments. It presents an original alternative to the concept of self-efficacy to evaluate fear of falling in older people.The model of FOF presented in this article is grounded on elderly people's experience. It gives an experiential description of the three dimensions constitutive of FOF and of their evolution as fear increases, and defines an evaluation tool using situations and wordings based on the elderly people's discourse.

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In coordination with a Technical Advisory Committee (TAC) consisting of County Engineers and Iowa DOT representatives, the Iowa DOT has proposed to develop a set of standards for a single span prefabricated bridge system for use on the local road system. The purpose of the bridge system is to improve bridge construction, accelerate project delivery, improve worker safety, be cost effective, reduce impacts to the travelling public by reducing traffic disruptions and the duration of detours, and allow local forces to construct the bridges. HDR Inc. was selected by the Iowa DOT to perform the initial concept screening of the bridge system. This Final Report summarizes the initial conceptual effort to investigate potential systems, make recommendations for a preferred system and propose initial details to be tested in the laboratory in Phase 2 of the project. The prefabricated bridge components were to be based on the following preliminary criteria set forth by the TAC. The criteria were to be verified and/ or modified as part of the conceptual development. - 24’ and 30’ roadway widths - Skews of 0o, 15o, and 30o - Span lengths of 30’ – 70’ in 10’ increments using precast concrete beams - Voided box beams could be considered - Limit precast element weight to 45,000 pounds for movement and placement of beams - Beams could be joined transversely with threaded rods - Abutment concepts may included precast as well as an option for cast-in-place abutments with pile foundations In addition to the above criteria, there was an interest to use a single-width prefabricated bridge component to simplify fabrication as well as a desire to utilize non-prestressed concrete systems where possible to allow for precasting of the beam modules by local forces or local precast plants. The SL-1 modular steel bridge rail was identified for use with this single span prefabricated bridge system.

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The main goal of CleanEx is to provide access to public gene expression data via unique gene names. A second objective is to represent heterogeneous expression data produced by different technologies in a way that facilitates joint analysis and cross-data set comparisons. A consistent and up-to-date gene nomenclature is achieved by associating each single experiment with a permanent target identifier consisting of a physical description of the targeted RNA population or the hybridization reagent used. These targets are then mapped at regular intervals to the growing and evolving catalogues of human genes and genes from model organisms. The completely automatic mapping procedure relies partly on external genome information resources such as UniGene and RefSeq. The central part of CleanEx is a weekly built gene index containing cross-references to all public expression data already incorporated into the system. In addition, the expression target database of CleanEx provides gene mapping and quality control information for various types of experimental resource, such as cDNA clones or Affymetrix probe sets. The web-based query interfaces offer access to individual entries via text string searches or quantitative expression criteria. CleanEx is accessible at: http://www.cleanex.isb-sib.ch/.

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The measurement of fat balance (fat input minus fat output) involves the accurate estimation of both metabolizable fat intake and total fat oxidation. This is possible mostly under laboratory conditions and not yet in free-living conditions. In the latter situation, net fat retention/mobilization can be estimated based on precise and accurate sequential body composition measurements. In case of positive balance, lipids stored in adipose tissue can originate from dietary (exogenous) lipids or from nonlipid precursors, mainly from carbohydrates (CHOs) but also from ethanol, through a process known as de novo lipogenesis (DNL). Basic equations are provided in this review to facilitate the interpretation of the different subcomponents of fat balance (endogenous vs exogenous) under different nutritional circumstances. One difficulty is methodological: total DNL is difficult to measure quantitatively in man; for example, indirect calorimetry only tracks net DNL, not total DNL. Although the numerous factors (mostly exogenous) influencing DNL have been studied, in particular the effect of CHO overfeeding, there is little information on the rate of DNL in habitual conditions of life, that is, large day-to-day fluctuations of CHO intakes, different types of CHO ingested with different glycemic indexes, alcohol combined with excess CHO intakes, etc. Three issues, which are still controversial today, will be addressed: (1) Is the increase of fat mass induced by CHO overfeeding explained by DNL only, or by decreased endogenous fat oxidation, or both? (2) Is DNL different in overweight and obese individuals as compared to their lean counterparts? (3) Does DNL occur both in the liver and in adipose tissue? Recent studies have demonstrated that acute CHO overfeeding influences adipose tissue lipogenic gene expression and that CHO may stimulate DNL in skeletal muscles, at least in vitro. The role of DNL and its importance in health and disease remain to be further clarified, in particular the putative effect of DNL on the control of energy intake and energy expenditure, as well as the occurrence of DNL in other tissues (such as in myocytes) in addition to hepatocytes and adipocytes.

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The concept of energy gap(s) is useful for understanding the consequence of a small daily, weekly, or monthly positive energy balance and the inconspicuous shift in weight gain ultimately leading to overweight and obesity. Energy gap is a dynamic concept: an initial positive energy gap incurred via an increase in energy intake (or a decrease in physical activity) is not constant, may fade out with time if the initial conditions are maintained, and depends on the 'efficiency' with which the readjustment of the energy imbalance gap occurs with time. The metabolic response to an energy imbalance gap and the magnitude of the energy gap(s) can be estimated by at least two methods, i.e. i) assessment by longitudinal overfeeding studies, imposing (by design) an initial positive energy imbalance gap; ii) retrospective assessment based on epidemiological surveys, whereby the accumulated endogenous energy storage per unit of time is calculated from the change in body weight and body composition. In order to illustrate the difficulty of accurately assessing an energy gap we have used, as an illustrative example, a recent epidemiological study which tracked changes in total energy intake (estimated by gross food availability) and body weight over 3 decades in the US, combined with total energy expenditure prediction from body weight using doubly labelled water data. At the population level, the study attempted to assess the cause of the energy gap purported to be entirely due to increased food intake. Based on an estimate of change in energy intake judged to be more reliable (i.e. in the same study population) and together with calculations of simple energetic indices, our analysis suggests that conclusions about the fundamental causes of obesity development in a population (excess intake vs. low physical activity or both) is clouded by a high level of uncertainty.

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We propose a class of models of social network formation based on a mathematical abstraction of the concept of social distance. Social distance attachment is represented by the tendency of peers to establish acquaintances via a decreasing function of the relative distance in a representative social space. We derive analytical results (corroborated by extensive numerical simulations), showing that the model reproduces the main statistical characteristics of real social networks: large clustering coefficient, positive degree correlations, and the emergence of a hierarchy of communities. The model is confronted with the social network formed by people that shares confidential information using the Pretty Good Privacy (PGP) encryption algorithm, the so-called web of trust of PGP.

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Introduction: Trastuzumab (T) is a cornerstone in the treatment of patients with HER2-overexpressing advanced breast cancer and development of resistance to T is a major therapeutic problem. HER-2 is part of a highly interactive signaling network that may impair efficacy of endocrine therapy. A sequential treatment design was chosen in this trial to ensure complete resistance to single agent therapy before receiving both a non-steroidal aromatase inhibitor (AI) and T. Any kind of clinical activity with combined treatment of AI and T after progression of single agent treatments could indicate restoration of sensitivity as a consequence of cross-talking and networking between both pathways. Methods: Key eligibility criteria included postmenopausal patients (pts.) with advanced, measurable, HER-2 positive (assessed by FISH, ratio (≥2)), HR positive disease and progression on prior treatment with a non-steroidal AI, e.g. letrozole or anastrozole, either in an adjuvant or advanced setting. Pts. received standard dose T monotherapy either weekly or three-weekly in step 1 and upon disease progression, continued T in combination with letrozole in step 2. The primary endpoint was clinical benefit response (CBR: CR, PR or SD for at least 24 weeks (+/- 1 week) according to RECIST) in step 2. Results: Thirteen pts. were enrolled in five centers in Switzerland. In step 1, six pts. (46%) achieved CBR. Median time to progression (TTP) was 161 days (Range: 50 - 627). Based on data collected until the end of May 2010, CBR was observed in seven out of the eleven evaluable pts. (64%) in step 2, including one pt. with partial response. Four of the seven pts. within step 2 that achieved CBR also had CBR in step 1. Seven out of eleven pts. have documented tumor progression during step 2 treatment. Median TTP for all eleven pts. was 184 days (range 61 - 471). Mean time on study treatment (TTP in step 1 plus TTP in step 2) for pts. reaching step 2 was 380 days (range 174 - 864). Adverse events were generally mild. Conclusion: Results of this proof-of-principle trial suggest that complete resistance to both AI and T can be overcome in a proportion of pts. by combined treatment of AI and T, as all pts. served as their own control. Our results appear promising for a new treatment strategy which offers a chemotherapy-free and well-tolerated option for at least a subset of the pts. with HR positive, HER-2 positive breast cancer. Further trials will need to corroborate this finding.

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Viime vuosikymmenien aikana kommunikaatioteknologiat ovat kehittyneet erittäin paljon. Uusia verkkoja, liityntätekniikoita, protokollia ja päätelaitteita on luotu alati kehittyvällä vauhdilla, eikä hidastumisen merkkejä ole näkyvissä. Varsinkin mobiilisovellukset ovat kasvattaneet markkinaosuuksiaan viime aikoina. Unlicensed MobileAccess (UMA) on uusi liityntätekniikka mobiilipäätelaitteille, joka mahdollistaa liitynnän GSM- runkoverkkoon WLAN- tai Bluetooth - tekniikoiden avulla. Tämä diplomityö keskittyy UMAan liittyviin teknologioihin, joita tarkastellaan lähemmin ensimmäisissä kappaleissa. Tavoitteena on esitellä, mitä UMA merkitsee, ja kuinka eri tekniikoita voidaan soveltaa sen toteutuksissa. Ennenkuin uusia teknologioita voidaan soveltaa kaupallisesti, täytyy niiden olla kokonaisvaltaisesti testattuja. Erilaisia testausmenetelmiä sovelletaan laitteistonja ohjelmiston testaukseen, mutta tavoite on kuitenkin sama, eli vähentää testattavan tuotteen epäluotettavuutta ja lisätä sen laatua. Vaikka UMA käsittääkin pääasiassa jo olemassa olevia tekniikoita, tuo se silti mukanaan uuden verkkoelementin ja kaksi uutta kommunikaatioprotokollaa. Ennen kuin mitään UMAa tukevia ratkaisuja voidaan tuoda markkinoille, monia erilaisia testausmenetelmiä on suoritettava, jotta varmistutaan uuden tuotteen oikeasta toiminnallisuudesta. Koska tämä diplomityö käsittelee uutta tekniikkaa, on myös testausmenetelmien yleisen testausteorian käsittelemiselle varattu oma kappale. Kappale esittelee erilaisia testauksen näkökulmia ja niihin perustuen rakennetaan myös testausohjelmisto. Tavoitteena on luoda ohjelmisto, jota voidaan käyttää UMA-RR protokollan toiminnan varmentamiseen kohdeympäristössä.