305,217 research outputs found
DEVELOPMENT OF ALTERNATIVE BIOENGINEERING STRATEGIES
No full textConcettualmente, la produzione additiva permette la rapida e precisa produzione delle parti complesse. La produzione additiva richiede di un disegno previo della parte da fabbricare per un software di progettazione assistita da computer (CAD, in inglese). A causa delle limitazioni del CAD software, particolarmente nelle curve, alcune delle parti stampate esige trattamenti aggiuntivi o di post lavorazione per ottenere la morfologia e la struttura desiderate. La produzione additiva e la stampa tridimensionale (3D) erano solo stabiliti nella area di ingegneria. Nell 210 secolo, la idea di usare le tecnologie di stampa tridimensionale per sviluppare delle strutture tridimensionale per il sostegno della coltura cellulare e de imitare il microambiente nativo, avanza una nuova area chiamata Biostampa. Nella biostampa, diverse technologie possono essere usate, essendo la stampa per estrusione la più versatile e consolidata. Le stampanti 3D come la 3D-BioplotterTM usano un nuovo metodo, la biostampa diretta, che permette la stampa di una struttura integrata con le cellule che assomiglia le condizioni in vivo. Allo stesso modo, diverse aree di recerca possono trarne beneficio della biostampa 3D, come lo studio di disturbi o malattie ad esempio il cancro. Per definizione, il cancro è una malattia eterogenea che provoca 10 milioni di morti nel mondo all’anno, essendo il carcinoma mammario la seconda causa di morte tra le donne negli Stati Uniti e Europa. Il carcinoma mammario triplo negativo (TNBC, in inglese) è stato descrito come un sottotipo molto aggressivo, però la mancanza di conoscenza di come inicia il processo tumorale rende il suo studio molto interesante. La combinazione di fibre elettrofilate e una linea cellulare del carcinoma mammario triplo negativo (MDA-MB-231), dimostra la formazione di aggregati cellulari simil-tumorali. Potrrebe esse usati nella medicina personalizata del cancro, selezionando il migliore trattamento per ogni paziente nel futuro.Conceptually, additive manufacturing allows rapid and precise manufacturing of complex parts. Additive manufacturing requires a previous design of the piece to be fabricated by computer-aided design (CAD) software. Due to the limitations of CAD software, especially on curves, some of the printed pieces require additional or post-processing treatments to achieve the desired morphology and structure. Additive manufacturing and three-dimensional (3D) printed were both previously established only in the engineering field. In the 21st century, the idea of using 3D printing technologies to develop 3D structures to support cell culture and mimic native cellular microenvironment, push forward a new field in research called Bioprinting. In bioprinting, several technologies can be used, being extrusion printing the more versatile and well established. 3D printers like the 3D-BioplotterTM use a new method, direct bioprinting, which permits the printing of a structure integrated with cells that resembles more to the in vivo conditions. Likewise, different research areas can benefit from 3D Bioprinting, like the study of disorders or diseases such as cancer. By definition, cancer is a heterogenic disorder that causes 10 million deaths worldwide, being breast cancer the second cause of death among women in the USA and Europe. Triple-negative breast cancer (TNBC) has been described as the most aggressive subtype, but the lack of knowledge on how the tumoral process begins makes its study more interesting. Combining electrospun fibers and a triple-negative breast cancer cell line (MDA-MB-231) demonstrates the formation of tumor-like cell aggregates. It might be used in personalized medicine of cancer by selecting the best treatment for each patient in the future
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Shoreline Extraction Methods from Sentinel-2 and PlanetScope Images
No full textThis work aims to compare and assess the performance of certain methodologies for shoreline mapping based on the use of medium (10 m) and high resolution (3 m) multi-spectral imagery, provided by Sentinel-2 (S2) and PlanetScope (PS), respectively. Being Sentinel-2 part of the Copernicus missions, its data are freely available. PS imagery are also freely available for scientific research, upon approval by the European Space Agency of a related project proposal. Several spectral indices, including Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI), Automated Water Extraction Index (AWEI), and Water Index (WI), were used for shoreline detection. In particular, two unsupervised classification techniques, the Gaussian Mixture Model (GMM) and K-means clustering were deployed as shoreline extraction methods. The outcomes of such approaches were validated using reference shorelines derived from aerial orthomosaics, generated from images acquired as close as possible to the satellite imagery dates, and the”baseline and transect” approach for accuracy verification. Three tide-less Mediterranean beaches were used as study cases for comparison: the beach between Castelldefels and Gava in Spain, Feniglia and Marina di Grosseto in Italy. The results demonstrated sub-pixel accuracy in shoreline extraction, with Mean Absolute Distances ranging from 2 m to 5 m for S2 data and 1.5 m to 2 m for PS data. These findings highlight the potential of freely available satellite data for semi-automatic shoreline detection. Results obtained by using the combination of different indices and methodologies show that the best option may change depending on the considered context, hence future investigations should be dedicated to the development of a procedure for automatically determining the context-based (close to) optimal index-classifier combination
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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, publisher and bookseller : a tripartite synergy in Nigerian book industry
No full textThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
[Report to Chief J. E. Curry, by an unknown author #2]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
[Report to Chief J. E. Curry, by an unknown author #1]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
Mining e-mail content for author identification forensics
No full textWe describe an investigation into e-mail content mining for author identification, or authorship attribution, for the purpose of forensic investigation. We focus our discussion on the ability to discriminate between authors for the case of both aggregated e-mail topics as well as across different email topics. An extended set of e-mail document features including structural characteristics and linguistic patterns were derived and, together with a Support Vector Machine learning algorithm, were used for mining the e-mail content. Experiments using a number of e-mail documents generated by different authors on a set of topics gave promising results for both aggregated and multi-topic author categorisation
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