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    Dual core quantum dots for highly quantitative ratiometric detection of trypsin activity in cystic fibrosis patients

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    : We present herein two colour encoded silica nanospheres (2nanoSi) for the fluorescence quantitative ratiometric determination of trypsin in humans. Current detection methods for cystic fibrosis diagnosis are slow, costly and suffer from false positives. The 2nanoSi proved to be a highly sensitive, fast (minutes), and single-step approach nanosensor for the screening and diagnosis of cystic fibrosis, allowing the quantification of trypsin concentrations in a wide range relevant for clinical applications (25-350 μg L(-1)). Furthermore, as trypsin is directly related to the development of cystic fibrosis (CF), different human genotypes, i.e. CF homozygotic, CF heterozygotic, and unaffected, respectively, can be determined using our 2nanoSi nanospheres. We anticipate the 2nanoSi system to be a starting point for non-invasive, easy-to-use and cost effective ratiometric fluorescent biomarkers for recessive genetic diseases like human cystic fibrosis. In a screening program in which the goal is to detect disease and also the carrier status, early diagnosis could be of great help

    Semiconductor Nanoparticles as Platform for Bio-Applications and Energy Related Systems

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    Aquesta tesi està dedicada a la síntesi, caracterització i aplicacions de diferents nanomaterials que presenten la propietat de ser semiconductors. Aquesta dividida en tres blocs, en els quals, en el primer d'ells es parla sobre quantum dots (QDs), que són nanoparticulas fluorescents la longitud d'ona d'emissió varia amb la mida. Aquests materials s'estan utilitzant últimament com a substituts dels colorants orgànics ja que presenten avantatges, la principal és que no perden la seva emissió amb el temps. Aquests QDs han estat usats per estudiar la seva interacció amb l'or (que augmenta la seva intensitat de fluorescència), han estat encapsulats usant polímers per usar-los com a controls en citometria de flux i per silica per usar-los (un cop units a un peptido i un colorant orgànic adequat) com a detectors de fibrosi quística. Finalment també han estat usats en aquesta tesi per intentar seguir el moviment d'un receptor en plaquetes. En el segon bloc de la tesi es parla de up conversió nanoparticles, la diferència enfront dels QDs és que s'exciten a major longitud d'ona a la que emeten, pel que són capaços d'absorbir en el infraroig i emetre en el visible, fent-ideals per a aplicacions en biologia. En aquesta tesi es van usar per a reconèixer un receptor en neutrofilos i per introduir-lo dins de hidrotalcites (material que no és reconegut pel cos com estrany) per així poder alliberar-ho en l'organisme. Finalment, en el tercer bloc s'han sintetitzat materials per catalisis (sulfur de bismut) i per cel·les solars (òxid de titani)Esta tesis esta dedicada a la sintesis, caracterizacion y aplicaciones de diferentes nanomateriales que presentan la propiedad de ser semiconductores. Esta dividida en tres bloques, en los cuales, en el primer de ellos se habla sobre quantum dots (QDs), que son nanoparticulas fluorescentes cuya longitud de onda de emision varia con el tamaño. Dichos materiales se estan usando ultimamente como sustitutos de los colorantes organicos ya que presentan ventajas, la principal es que no pierden su emision con el tiempo. Estos QDs han sido usados para estudiar su interaccion con el oro (que aumenta su intensidad de fluorescencia), han sido encapsulados usando polimeros para usarlos como controles en citometria de flujo y por silica para usarlos (una vez unidos a un peptido y un colorante organico adecuado) como detectores de fibrosis quistica. Finalmente tambien han sido usados en esta tesis para intentar seguir el movimiento de un receptor en plaquetas. En el segundo bloque de la tesis se habla de up conversion nanoparticles, cuya diferencia frente a los QDs es que se excitan a mayor longitud de onda a la que emiten, por lo que son capaces de absorber en el infrarojo y emitir en el visible, haciendolos ideales para aplicaciones en biologia. En esta tesis se usaron para reconocer un receptor en neutrofilos y para introducirlo dentro de hidrotalcitas (material que no es reconocido por el cuerpo como extraño) para asi poder liberarlo en el organismo. Finalmente, en el tercer bloque se han sintetizado materiales para catalisis (sulfuro de bismuto) y para celdas solares (oxido de titanio).This thesis is dedicated to the synthesis, characterization and application of different nanomaterials that are semiconductors. It is divided in three blocks, in the first one we talk about quantum dots (QDs), that are fluorescent nanoparticles whose wavelength of emission changes with size. Such materials are being used as substitutes of organic dyes, due to the many advantages they present, the main one is that the fluorescence is not lost with time. These QDs have been used to study their interaction with gold ( that increases the fluorescence intensity), they have been encapsulated with polimers to be used as controls in flow cytometry or by silica to use them as sensors for cystic fibrosis (once they have been attatched to the right polymer and dye). Finally, in this thesis, they have been also used to track the movement of a platelet receptor. In the second block we talk about up conversion nanoparticles, which only difference regarding QDs is that they are excited using a longer wavelength than the emission, so they are able to absorb in the infrared and emit in the visible range of light, making them ideal for biological applications. We have use this materials to recognice an specific receptor in neutrophils as well as to be surrounded by hydrotalcite (body friendly material) so it can be released in the organism. Finally, in the third block we have syntesized materials for catalysis (bismuth sulfide) and for solar cells (titanium oxide for perovskite solar cells)

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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