997 resultados para Neutrino masses
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Purpose: Precise diagnosis of DVT of the legs is a challenging problem, not only in front of suspicion of PE, but also in all status of leg pain, warmth and swelling. Clinical diagnosis has a low accuracy and further investigations are mandatory in order to diagnose DVT. Amongst the possible investigations, US has a high specificity and a good NPV. However, many pathologies unrelated to the veins may mimic the signs and symptoms of DVT and have to be recognized in order to make the correct diagnosis. The purpose of this paper is to review the results of the US investigations of the legs performed in our Department during the last three years for a suspicion of DVT and describe alternative diagnoses mimicking DVT. Methods and materials: Through a RIS-based search, we retrospectively reviewed all the cases of US of the legs performed in our Department between January 2006 and December 2008 for a suspicion of DVT. We selected the cases of positive findings unrelated to the veins and illustrated these findings with characteristic images. Results: 419 US of the legs were performed between December 2006 and December 2008 for a suspicion of DVT. Among these, 75 were positive for DVT, and 79 for alternative diagnosis. The most common alternative diagnosis was edema of the legs (31%), followed by hematoma (23%). Other findings were Baker cysts (13%), cellulitis (10%) and lymphoceles (5%). Rare diagnoses were arterio-venous malformations, pseudoaneurysms, pelvic masses, necrosing fasciitis, intramuscular abscesses, subcutaneous seromas, sarcoma and ganglion cysts. Conclusion: A greater knowledge of the US appearance of the pathologies mimicking DVT may help to make the correct diagnosis, avoiding further expensive investigations or inappropriate anticoagulant therapy.
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Report for the scientific sojourn carried out at the Institut National d'Histoire de l'Art (INHA), France, from 2010 to 2012. It has focused on the analysis and editing of tales of human apparitions from the other world belonging to the Catalan culture or referring to it. We have studied and edited different versions of the process of Esperança Alegre (Lleida, 1500) and the Peregrinació del Venturós Pelegrí. These medieval works have been preserved in sources of the late sixteenth century or later. We have located a manuscript of the Esperança Alegre's tale, unknown to us at the beginning of this research (Biblioteca Nacional de España, ms. 1701), which differs from the version of ms. Baluze 238 of the Bibliothèque Nationale de France. The scribe of the ms. 1701 adds several paragraphs where considers the case as a diabolical phantasmagoria. About the Venturós Pelegrí, we have tried to establish firm criteria for the classification of many editions from the seventeenth to nineteenth centuries. We have been looking for printed books in the libràries of the world and we have made several requests for photographic reproductions, in order to classify undated editions by comparing woodcuts and other decorative elements. In the legend of Prince Charles of Viana (1421-1461), the appearances of his ghost are accompanied by rumors of his poisoning and of his sanctity. In addition, we have studied the cycles of masses for the souls in Purgatory linked to the hagiographies of St. Amadour and St. Vincent Ferrer, as well as the appearances described in L'Ànima d’Oliver of Francesc Moner, in the Carmelite chronicles of Father John of St. Joseph (1642-1718) and in some folktales collected from the eighteenth to the twentieth century. All this have allowed us to verify the evolution of certain cultural paradigms since the Middle Ages to the present.
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The importance of entrepreneurship for social and economic growth is generally accepted. In addition, intrapreneurship or corporate entrepreneurship is recognized as one of the key elements for organizational development. In this context, corporate culture and, specifically, entrepreneurial competences are considered to be catalysts for intrapreneurship. The main purpose of this paper is to analyse the influence of resources and capabilities on the probability of becoming an intrapreneur. Using data obtained from the Global Entrepreneurship Monitor (GEM) for 39 countries, and a logistic model, the study shows that entrepreneurial resources and capabilities, such as previous entrepreneurial experience, entrepreneurial competences and the ability to detect business opportunities, influence intrapreneurial behaviour. The contributions of this research are both conceptual (advancing corporate entrepreneurship theory) and practical (relating to the design of policies to foster intrapreneurial activities).
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Purpose: The paper analyzes the micro-angels investment behaviour, looking both to the criteria used in the selection of their investment projects and to the characteristics of their guidance role during the investment period. Design/Methodology/Approach: The paper focuses on a double bottom line movement of French micro-angels clubs that has been operating since 1983. Our primary source of data is an online survey carried out during March 2012, asking members of clubs all over France for different aspects of their procedures. Findings: Our findings suggest that micro-angels are interested in small, socially or environmentally friendly projects having the potential to contribute to the development of their neighbourhood. We find that women are even more interested than men in such projects. Educated micro-angels value entrepreneurial motivation and understanding of the project more than less-educated micro-angels. We also point out the factors that micro-angels consider important in accompanying enterprises. Here we find that gender makes little difference. However, retired micro-angels value financial diagnosis made conjointly with entrepreneurs, while both active micro-angels and educated micro-angels value more the use of their network to help micro-entrepreneurs. Practical/Social Implications: Given the potential benefits of micro-angels investing and guiding the development of micro-enterprises, a social micro-angel investment on a major scale in developing countries could help in tackling some of the problems faced by the development of microfinance, such as the over-indebtedness of micro-entrepreneurs. Practitioners and new initiatives would gain from understanding what adaptations need to be made. Originality/value: We expect to add to the venture capital theory to take into account non-economic motives.
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Given that firms develop their activities in a network of multiple players, interfirm rivalry is not only a matter of direct competitors, but also of indirect competition. In spite of this, the literature on competitive dynamics tends to focus on analyzing rivalry as an exclusive function of the competitive relationship between a focal firm and its direct rivals. In this article, we extend competitive dynamics literature by considering how focal firms are affected by the relationships of their rivals with third-party firms. Specifically, we study the effect that the multimarket contacts of rivals produces on the performance of the focal firm. Additionally, we incorporate the idea that there are different strategic options for operating in an industry that affect the intensity of multimarket contact externalities. Our results show that multimarket contact among firms causes externalities that indirectly affect firms that are not directly involved in this competitive relationship. We find that multimarket contact externalities differ between and within strategic groups.
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This study explores whether firms have differential price-earnings multiples associated with their means of achieving a sequential pattern of increasing positive earnings. Our main findings show that market participants assign higher price-earnings multiples to firms when their pattern of increasing earnings is supported by the same pattern of increasing cash flows. Market participants assign lower price-earnings multiples to firms suspect of having engaged in accrual-based earnings management, sales manipulation, and overproduction to achieve the earnings pattern. We find, however, that market participants do not penalize firms suspect of having achieved the earnings pattern through the opportunistic reduction of discretionary expenses.
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Annotation of protein-coding genes is a key goal of genome sequencing projects. In spite of tremendous recent advances in computational gene finding, comprehensive annotation remains a challenge. Peptide mass spectrometry is a powerful tool for researching the dynamic proteome and suggests an attractive approach to discover and validate protein-coding genes. We present algorithms to construct and efficiently search spectra against a genomic database, with no prior knowledge of encoded proteins. By searching a corpus of 18.5 million tandem mass spectra (MS/MS) from human proteomic samples, we validate 39,000 exons and 11,000 introns at the level of translation. We present translation-level evidence for novel or extended exons in 16 genes, confirm translation of 224 hypothetical proteins, and discover or confirm over 40 alternative splicing events. Polymorphisms are efficiently encoded in our database, allowing us to observe variant alleles for 308 coding SNPs. Finally, we demonstrate the use of mass spectrometry to improve automated gene prediction, adding 800 correct exons to our predictions using a simple rescoring strategy. Our results demonstrate that proteomic profiling should play a role in any genome sequencing project.
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Particle physics studies highly complex processes which cannot be directly observed. Scientific realism claims that we are nevertheless warranted in believing that these processes really occur and that the objects involved in them really exist. This dissertation defends a version of scientific realism, called causal realism, in the context of particle physics. I start by introducing the central theses and arguments in the recent philosophical debate on scientific realism (chapter 1), with a special focus on an important presupposition of the debate, namely common sense realism. Chapter 2 then discusses entity realism, which introduces a crucial element into the debate by emphasizing the importance of experiments in defending scientific realism. Most of the chapter is concerned with Ian Hacking's position, but I also argue that Nancy Cartwright's version of entity realism is ultimately preferable as a basis for further development. In chapter 3,1 take a step back and consider the question whether the realism debate is worth pursuing at all. Arthur Fine has given a negative answer to that question, proposing his natural ontologica! attitude as an alternative to both realism and antirealism. I argue that the debate (in particular the realist side of it) is in fact less vicious than Fine presents it. The second part of my work (chapters 4-6) develops, illustrates and defends causal realism. The key idea is that inference to the best explanation is reliable in some cases, but not in others. Chapter 4 characterizes the difference between these two kinds of cases in terms of three criteria which distinguish causal from theoretical warrant. In order to flesh out this distinction, chapter 5 then applies it to a concrete case from the history of particle physics, the discovery of the neutrino. This case study shows that the distinction between causal and theoretical warrant is crucial for understanding what it means to "directly detect" a new particle. But the distinction is also an effective tool against what I take to be the presently most powerful objection to scientific realism: Kyle Stanford's argument from unconceived alternatives. I respond to this argument in chapter 6, and I illustrate my response with a discussion of Jean Perrin's experimental work concerning the atomic hypothesis. In the final part of the dissertation, I turn to the specific challenges posed to realism by quantum theories. One of these challenges comes from the experimental violations of Bell's inequalities, which indicate a failure of locality in the quantum domain. I show in chapter 7 how causal realism can further our understanding of quantum non-locality by taking account of some recent experimental results. Another challenge to realism in quantum mechanics comes from delayed-choice experiments, which seem to imply that certain aspects of what happens in an experiment can be influenced by later choices of the experimenter. Chapter 8 analyzes these experiments and argues that they do not warrant the antirealist conclusions which some commentators draw from them. It pays particular attention to the case of delayed-choice entanglement swapping and the corresponding question whether entanglement is a real physical relation. In chapter 9,1 finally address relativistic quantum theories. It is often claimed that these theories are incompatible with a particle ontology, and this calls into question causal realism's commitment to localizable and countable entities. I defend the commitments of causal realism against these objections, and I conclude with some remarks connecting the interpretation of quantum field theory to more general metaphysical issues confronting causal realism.
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During ODP Leg 123, abundant and well-preserved Neocomian radiolarians were recovered at Site 765 (Argo Abyssal Plain) and Site 766 (lower Exmouth Plateau). Assemblages are characterized by the numerical dominance of a small number of non-tethyan forms and by the scarcity of tethyan taxa. Remarkable contrasts exist between radiolarian assemblages extracted from claystones of Site 765 and reexamined DSDP Site 26 1, and faunas recovered from radiolarian sand layers, only found at Site 765. Clay faunas are unusual in their low diversity of apparently ecologically tolerant (or solution resistant?), ubiquist species, whereas sand faunas are dominated by non-tethyan taxa. Comparisons with Sites 766 and 26 1, as well as sedimentological observations, lead to the conclusion that this faunal contrast resulted from a difference in provenance, rather than from hydraulic sorting or selective dissolution. The ranges of 27 tethyan taxa from Site 765 were compared to the tethyan radiolarian zonation by Jud (1992) by means of the Unitary Associations Method. This calculation allows to directly date the Site 765 assemblages and to estimate the amount of truncation of ranges for tethyan taxa. Over 70% of the already few tethyan species of Site 765, have truncated ranges during the Valanginian-Hauterivian. Radiolarian assemblages recovered from claystones at Sites 765 and 261 in the Argo Basin apparently reflect restricted oceanic conditions during the latest Jurassic-Barremian. Neither sedimentary facies nor faunal associations bear any resemblance to what we know from typical tethyan sequences. We conclude that the Argo Basin was paleoceanographically separated from the Tethys during the Late Jurassic and part of the Early Cretaceous by its position at higher paleolatitudes and/or by enclosing land masses. Assemblages recovered from radiolarian sand layers are dominated by non-tethyan species that are interpreted as circumantarctic. Their first appearance in the late Berriasian-early Valanginian predates the oceanization of the Indo-Australian breakup (M11, late Valanginian), but coincides with a sharp increase in margin-derived pelagic turbidites. The Indo-Australian rift zone and the adjacent margins must have been submerged deeply enough to allow an intermittent influx of circumantarctic cold water into the Argo Basin, creating increased bottom current activity. Cold-water radiolarians carried into the Argo Basin upwelled along the margin, died, and accumulated in radiolarite layers due to winnowing by bottom currents. High rates of faunal change and the sharp increase of bottom current activity are thought to be synchronous with possible pronounced late Berriasian-early Valanginian lowstands in sea level. Hypothetically, both phenomena might have been.caused by a tendency to glaciation on the Antarctic-Australian continent, which was for the first time isolated from the rest of Gondwana by oceanic seaways as a result of Jurassic-Early Cretaceous sea-floor spreading. The absence of most typical tethyan radiolarian species during the Valanginian-Hauterivian is interpreted as reflecting a time of strong influx of circumantarctic cold water following oceanization (M11) and rapid spreading between Southeast India and West Australia. The reappearance and gradual abundance/diversity increase of tethyan taxa, along with the still dominant circumantarctic species are thought to result from overall more equitable climatic conditions during the Barremian-early Aptian and from the establishment of an oceanic connection with the Tethys Ocean during the early Aptian.
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Hi ha records que perduraran sempre; el gol d’Iniesta contra el Chelsea, la boleia de Zidane a Hampden Park… Aquests moments memorables que queden gravats a les retines de tots nosaltres i produeixen una immensa felicitat a l’ésser humà, que l’emocionen, que el fan casi plorar. Tot això es produeix gràcies a un esport de masses molt present en les nostres vides, el futbol. Una activitat merament esportiva que s’ha convertit, amb el pas dels anys, en quelcom més que un esport, ha travessat l’àmbit purament sentimental d’una regió fins a assolir nivells d’autèntica globalització arreu del món. I és precisament el fet que el futbol porta una immensa passió a tots els racons de la societat, el que fa plantejar-nos el funcionament d’aquesta gran indústria de l’entreteniment.La realitat, tanmateix, revela l’existència de tot un món econòmico-empresarial que s’amaga darrere aquest espectacle, del qual, els veritables protagonistes són els clubs de futbol. Sense ells no es produiria mai l’espectacle. És per aquest motiu, que centrarem el nostre anàlisi sobre aquestes entitats esportives: veure el seu funcionament en la seva vessant més econòmica (1).En el present estudi s’analitzarà tot el funcionament intern d’un club, des del seu marc legal fins a l’econòmic, parant molta atenció en el que és el mercat futbolístic, el qual, al cap i a la fi, acaba relacionant la part més esportiva amb l’empresarial. A partir d’aquí intentarem extrapolar aquest entramat al que és el món futbolístic en general.Amb això, intentarem qüestionar-nos el perquè del gran moviment de divises existent, actualment, en aquest esport. Com pot ser que un club inverteixi més de 30 milions d’euros (2) només en el que seria contractar un nou treballador? Com es podengenerar tants recursos per després gastar-los en nòmines astronòmiques pels jugadors?Doncs aquest seguit de qüestions es el que pretenem respondre en aquest treball, de la forma més amena i clara possible, amb els gràfics i taules més adients.(1) Com que de clubs de futbol n’hi ha molts i no els podem analitzar tots un per un, partirem de la based’agafar-ne un com a model, en aquest cas, per la seva proximitat i facilitat d’obtenció de dades hemescollit el FC Barcelona.(2) Quantitat que equival, ni més ni menys, a 500 vegades el sou d’un treballador mitjà al llarg de tota la seva vida
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Segurament us sonarà aquest eslògan: Nespresso, What else? Café, cuerpo y alma. Segurament, si us mencionem a l’actor George Clooney, ja no només l’identifiqueu amb una de les seves pel·lícules, sinó que directament us ve laimatge de l’anunci que protagonitza per Nespresso. I fins i tot, segurament, molts dels que esteu llegint aquest text, no us heu pogut resistir a la temptació i ja disposeu d’una màquina Nespresso a casa vostra. Nespresso s’ha convertiten un fenomen de masses i en una de les empreses que més està creixent en aquests últims anys. Per tots aquests motius, a l’hora de triar quin seria l’eix fonamental del nostre treball, vam decantar-nos per aquesta empresa.El que pretenem amb aquest treball és esbrinar tots els passos que s’han de seguir per a llençar un nou producte al mercat i analitzar la importància que té el marketing per a les empreses d’avui dia. Hem emmarcat aquests dos objectius dins de l’empresa Nespresso, i és per això que portarem a terme el llançament d’una nova càpsula d’un gust original, analitzarem com serà el seu procés productiu i dissenyarem les possibles tècniques de promoció per tal que tingui èxit. Pel que fa al segon objectiu, comprovarem mitjançant un experiment el grau d’influència que té el marketing sobre els clients.Referent a les conclusions que hem extret amb el nostre treball, aquestes són, per una part, la creació de Crème Noisette, una nova càpsula que no us deixarà indiferents; i per l’altra, que Nespresso basa el seu èxit en la qualitat, però sempre acompanyada d’una gran campanya de marketing.Voleu continuar descobrint els secrets que amaga el llançament d’una nova càpsula? Voleu saber si la gent aprecia realment totes les varietats que ofereix Nespresso? Per a descobrir-ho, us convidem a llegir el nostre treball.
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Partiendo de la capacidad expresiva y reflexiva que albergan las imágenes tecnológicas para manifestar la red de implicaciones que se configuran en un sistema de representación como el que se desarrolla durante una exhibición de Capoeira, el propósito que me planteo en este trabajo consiste en abrazar el gran desafío del saber contemporáneo de educar(se) ‘en’ y ‘para’ la era planetaria, es decir, desatar un impulso de pensamiento complejo que esté animado por una tensión permanente entre la aspiración a un saber no parcelado, no dividido, no reduccionista, y el reconocimiento de lo inacabado e incompleto de todo conocimiento La aventura especulativa que se desencadena en esta investigación parte de una posición propia declarada: el análisis histórico, estético y antropológico de los fundamentos culturales que se despliegan durante una roda de Capoeira nos sirve para detectar categorías conceptuales que permiten esbozar la delimitación de un territorio metafórico donde se ilustra el carácter epistémico adscrito a la visualidad de alguno de los dispositivos y formas audiovisuales que configuran los entornos digitales comunicativos que habitamos en la actualidad
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Introduction : Les tumeurs solides pseudo-papillaires du pancréas (SPT) sont des tumeurs rares, d'étiopathogénie encore incertaine.Le but de notre travail était de décrire les caractéristiques radiologiques des SPT dans le groupe d'âge pédiatrique et d'étudier leur corrélation avec les études anatomopathologiques en vue d'établir un diagnostic.Patients et Méthodes : Nous avons étudié rétrospectivement trois malades pédiatriques pour lesquelles le diagnostic de tumeur solide pseudo-papillaire du pancréas a été porté à l'examen d'une pièce opératoire. Ce groupe comprenait 3 jeunes filles et femmes (âge médian: 13 ans).Résultats : La tumeur a été découverte pendant le bilan de symptômes digestifs non spécifiques. Les examens biologiques n'étaient pas informatifs. Des investigations radiologiques complètes ont été réalisées y compris les ultrasons (US), la tomodensitométrie (CT) et l'imagerie par résonance magnétique (IRM).Celles-ci ont montré de volumineuses lésions nodulaires, peu vascularisées, de compositions habituellement hétérogènes, avec des composantes kystiques et hémorragiques identifiées dans les 3 cas. Un traitement chirurgical a été pratiqué chez toute les patientes. L'étude de la pièce opératoire a montré une tumeur encapsulée dans les 3 cas. Aucune métastase n'a été mise en évidence.Conclusion : Les SPT doivent être considérées dans le diagnostic différentiel des masses pancréatiques pédiatriques, en particulier chez les adolescentes. Certaines caractéristiques radiologiques comme des masses volumineuses bien circonscrites, des lésions hétérogènes avec des zones kystiques et hémorragiques, de plus entourées d'une pseudocapsule fibreuse réactive, suggèrent fortement le diagnostic de SPT. Celui-ci devrait ensuite être confirmé par une biopsie avant que la résection chirurgicale soit effectuée. Chez les enfants, Γ écho graphie abdominale reste la méthode de première intention, suivie par l'IRM comme technique d'imagerie de choix pour évaluer les caractéristiques et l'extension de la lésion, tout en évitant l'exposition des patients aux rayonnements ionisants.
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OBJECTIVE: To determine the usefulness of computed tomography (CT), magnetic resonance imaging (MRI), and Doppler ultrasonography (US) in providing specific images of gouty tophi. METHODS: Four male patients with chronic gout with tophi affecting the knee joints (three cases) or the olecranon processes of the elbows (one case) were assessed. Crystallographic analyses of the synovial fluid or tissue aspirates of the areas of interest were made with polarising light microscopy, alizarin red staining, and x ray diffraction. CT was performed with a GE scanner, MR imaging was obtained with a 1.5 T Magneton (Siemens), and ultrasonography with colour Doppler was carried out by standard technique. RESULTS: Crystallographic analyses showed monosodium urate (MSU) crystals in the specimens of the four patients; hydroxyapatite and calcium pyrophosphate dihydrate (CPPD) crystals were not found. A diffuse soft tissue thickening was seen on plain radiographs but no calcifications or ossifications of the tophi. CT disclosed lesions containing round and oval opacities, with a mean density of about 160 Hounsfield units (HU). With MRI, lesions were of low to intermediate signal intensity on T(1) and T(2) weighting. After contrast injection in two cases, enhancement of the tophus was seen in one. Colour Doppler US showed the tophi to be hypoechogenic with peripheral increase of the blood flow in three cases. CONCLUSION: The MR and colour Doppler US images showed the tophi as masses surrounded by a hypervascular area, which cannot be considered as specific for gout. But on CT images, masses of about 160 HU density were clearly seen, which correspond to MSU crystal deposits.
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Modern methods of compositional data analysis are not well known in biomedical research.Moreover, there appear to be few mathematical and statistical researchersworking on compositional biomedical problems. Like the earth and environmental sciences,biomedicine has many problems in which the relevant scienti c information isencoded in the relative abundance of key species or categories. I introduce three problemsin cancer research in which analysis of compositions plays an important role. Theproblems involve 1) the classi cation of serum proteomic pro les for early detection oflung cancer, 2) inference of the relative amounts of di erent tissue types in a diagnostictumor biopsy, and 3) the subcellular localization of the BRCA1 protein, and it'srole in breast cancer patient prognosis. For each of these problems I outline a partialsolution. However, none of these problems is \solved". I attempt to identify areas inwhich additional statistical development is needed with the hope of encouraging morecompositional data analysts to become involved in biomedical research