1,720,991 research outputs found
Dimora linguaggio e tipo: dal lessico al costrutto. Il caso di Sauris
No full textIn questo lavoro si pongono in evidenza i caratteri tipologici delle architetture locali. Ci si sofferma inoltre sul ruolo del linguaggio orale nella interpretazione dell’evoluzione del tipo edilizio. In questo contesto viene rilevato l’importante ruolo delle dinamiche socio linguistiche e della glottologia in un contesto di migrazione che coinvolge la stessa tecnologia costruttiv
Monitoring the degradation of bone elastic properties induced by microgravity: a proposal.
No full textBackground
Important alterations occurring in living organisms during space flight concern the trabecular compartment of load-bearing bones, and result in significant bone mineral loss and decay of mechanical properties [1, 2].
Composition, mineral content, and the complex micro-scale trabecular microarchitecture contribute together to the macro-scale functional strength of bone as a whole [3]. Bone alterations, including those due to reduced gravitational load conditions, are mainly assessed by measuring bone density, even though, alone, it cannot comprehensively assess skeletal integrity [4]. Micro-tomographic techniques [5], not suitable for monitoring, allow for a pre- and post-mission examination of the trabecular bone component, which undergoes the fastest and most important alterations, placing astronauts at serious risk of fracture upon re-entry [5]. Mesoscale studies in modeled microgravity conditions combined with numerical simulations, show that degradation of apparent mechanical properties must be considered to achieve an accurate description of bone performance [6, 7].
To quantify the pathological alterations in the bone micro-architecture in a clinical setting, a patented, CE marked, software medical device, the Bone Elastic Structure Test, BES TEST, has been developed. Results are uncorrelated to BMD and independent of load [8, 9]. BES TEST has a diagnostic accuracy of 78% as a 3-year fracture risk estimator [10] and can be used to complete the densitometry picture and as monitoring tool for bone follow-up in in rheumatology [9], oncology [11], nephrology [12] and rare bone diseases [13].
Its prospective application for bone alteration monitoring during spaceflights is discussed.
Method
BES TEST simulates the application of forces on an X-ray functional biopsy of the patient’s hand [14-19]. Results are combined in an index, BSI, and its T-score and Z-score (Fig.1). Characteristics: X-ray dose < 0.0005 μSV; CV intra-operator=0.06; 95%CI±8 BSI; CV inter-operator =0.11; 95% CI=±10.8 BSI [20, 21], in line with the diagnostic gold standard.
Requirements for investigation of BES TEST space application:
- Acquisition: x-ray scanner, small detector. Several possible arrangements are possible, tests in simulated space flight will clarify the best configuration.
- Calibration: the acquisition set-up will likely differ from the clinical one.
- Analysis: radiograms upload to automatic service.
Results
BES TEST monitors trabecular bone, which changes more rapidly than cortical bone and BMD in response to physio-pathological alterations, like those occurring during spaceflight.
Conclusion
BESTEST is fast, easy to perform, cost-effective and can be significantly repeated within just weeks, showing potential for monitoring the changes in bone functionality during long-duration space missions.
Acknowledgements
Area Science Park financially supported the development of this work at various stages.
References
1. Vico, L. et al. Bone. 1998.
2. Lang, T. et al. J Bone and Mineral Research. 2004.
3. Kleerekoper, M. et al. Calcif Tissue Int. 1985.
4. J.D. Sibonga et al. Aerosp.Med.Hum. perform. 2015.
5. J.D. Sibonga et al. J. Clin. Densitom. 2020.
6. Cosmi F. et al. J. Mech. Behav. Biomed. Mater. 2009
7. Francesca Cosmi et al. J. Mech. Behav. Biomed. Mater. 2015
8. Cosmi F et al. Mater Today: Proc. 2018.
9. Saviola G. et al. Minerva Medica. 2019.
10. Francesca Cosmi et al. 2023.
11. S. Saracchini et al. 2019.
12. M. Ferraro et al. NDT. 2021.
13. Cosmi F and Maximova N. Mater. Today. 2019
14. Wilczek M. L et al. Eur Radiol. 2013.
15. Albanese CV et al. R. Radiol Med. 2011.
16. Alenfeld FE et al. Osteoporosis Int. 1998.
17. Mele R. Osteoporos Int. 1997.
18. Tonti E. Computer Modeling in Engineering and Science. 2001.
19. Cosmi F. Molecular and Cellular Biology. 2015.
20. Cosmi F. et al. Proc IMechE Part C. 2022.
21. Cosmi F. et al. Proc IMechE Part C. 2023
Implementation of correctness criteria for the bone structure analysis by means of a hand-held x-ray system
Full text linkDensitometry alone has been shown to be inadequate to predict all osteoporotic fractures, since 40-50% occur in people who do not have a low bone density. The BESTEST®, Bone Elastic Structure Test, virtually simulates compressive loads on the trabecular architecture’s reconstructions obtained from digital radiographs of first proximal epiphyses of the non-dominant hand. The radiograms are acquired by a hand-held portable x-ray system equipped with a digital sensor. While in certain cases these systems present risks that are no greater than with standard systems, issues related to: (i) position of the handheld X-ray device relative to the operator, (ii) risk of misalignment of the X-ray units during exposure, (iii) patient protection and (iv) correct positioning of the sensor must still be addressed. A special stand and a customized sensor holder have been therefore designed, so that safety for patient and operator and repeatability of the exam have been improved
Come stanno le tue ossa? Nuovi strumenti diagnostici per la salute dell'osso
No full textIntervengono Francesca Cosmi, docente di Progettazione meccanica e Costruzione di macchine dell'Università di Trieste e Alessandra Nicolosi, amministratore delegato M2TES
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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