1,721,072 research outputs found
Established paths and new avenues: A review of the main radiological techniques for investigating sarcopenia
Full text linkSarcopenia is a clinical condition mainly affecting the elderly that can be associated in a long run with severe consequences like malnutrition and frailty. Considering the progressive ageing of the world population and the socio-economic impact of this disease, much effort is devoted and has to be further focused on an early and accurate diagnostic assessment of muscle loss. Currently, several radiological techniques can be applied for evaluating sarcopenia. If dual-energy X-ray absorptiometry (DXA) is still considered the main tool and it is even recommended as reference by the most current guidelines of the European working group on sarcopenia in older people (EWGSOP), the role of ultrasound (US), computed tomography (CT), peripheral quantitative CT (pQCT), and magnetic resonance imaging (MRI) should not be overlooked. Indeed, such techniques can provide robust qualitative and quantitative information. In particular, regarding MRI, the use of sequences like diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), magnetic resonance spectroscopy (MRS) and mapping that could provide further insights into the physiopathological features of sarcopenia, should be fostered. In an era pointing to the quantification and automatic evaluation of diseases, we call for future research extending the application of organ tailored protocols, taking advantage of the most recent technical developments
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
Diagnostic value of PET/MR with DWI for burkitt lymphoma
Full text link18F-FDG-PET/MR images, including DWI, of a 46-year-old male admitted to the Emergency Room of our tertiary center, who was suffering from diplopia, left orbital pain, and a headache for two weeks, demonstrated multiple hepatic nodules, a pancreatic mass, and skeletal metastases, in addition to thrombosis of the left cavernous sinus, thickening of the small intestine, and a large hepatic lesion identified at head and neck MR and whole-body CT, respectively. Hepatic and bone marrow biopsies revealed the diagnosis of Burkitt lymphoma. After four cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, methotrexate/ifosfamide, etoposide, and high dose cytarabine (R-CODOX-M/IVAC), a complete metabolic response occurred
The ‘Tree trunk and root’ model: key imaging findings may anatomically differentiate axial psoriatic arthritis and DISH from axial spondyloarthropathy
No full textVariable axial skeleton inflammation and axial skeleton tissue remodelling with aberrant ligamentous soft-tissue ossification occurs across the axial spondyloarthritis (ax-SpA) axial psoriatic arthritis (ax-PsA) and the diffuse idiopathic skeletal hyperostosis (DISH) spectrum. In this article, we show how imaging has resulted in an enthesis-centric model for different disease pathology compartmentalisation or a ‘root and trunk’ model for pathological process development. Whilst ankylosing spondylitis is predominantly characterised by early entheseal bony anchorage-related osteitis (root inflammation) and DISH is characterised by ligamentous soft-tissue ossification, ax-PsA is more heterogenous. Whilst ax-PsA may share an identical osteitis pattern to ax-SpA, a substantial proportion of ax-PsA cases have a soft tissue or tree trunk pathology that manifests as back pain with lack of osteitis but prominent ligamentous trunk ossification at later stages. We illustrate this using different imaging modalities to create a base for imaging research to elucidate this pattern of pathology
A practical integrated radiomics model predicting intensive care hospitalization in COVID-19
Full text linkQuantitative Imaging in Inflammatory Arthritis: Between Tradition and Innovation
No full textRadiologic imaging is crucial for diagnosing and monitoring rheumatic inflammatory diseases. Particularly the emerging approach of precision medicine has increased the interest in quantitative imaging. Extensive research has shown that ultrasound allows a quantification of direct signs such as bone erosions and synovial thickness. Dual-energy X-ray absorptiometry and high-resolution peripheral quantitative computed tomography (CT) contribute to the quantitative assessment of secondary signs such as osteoporosis or lean mass loss. Magnetic resonance imaging (MRI), using different techniques and sequences, permits in-depth evaluations. For instance, the perfusion of the inflamed synovium can be quantified by dynamic contrast-enhanced imaging or diffusion-weighted imaging, and cartilage injury can be assessed by mapping (T1ρ, T2). Furthermore, the increased metabolic activity characterizing the inflammatory response can be reliably assessed by hybrid imaging (positron emission tomography [PET]/CT, PET/MRI). Finally, advances in intelligent systems are pushing forward quantitative imaging. Complex mathematical algorithms of lesions' segmentation and advanced pattern recognition are showing promising results
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
Sharp ultimate velocity bounds for the general solution of some linear second order evolution equation with damping and bounded forcing
Full text linkWe consider a class of linear second order differential equations with damping and external force. We investigate the link between a uniform bound on the forcing term and the corresponding ultimate bound on the velocity of solutions, and we study the dependence of that bound on the damping and on the “elastic force”. We prove three results. First of all, in a rather general setting we show that different notions of bound are actually equivalent. Then we compute the optimal constants in the scalar case. Finally, we extend the results of the scalar case to abstract dissipative wave-type equations in Hilbert spaces. In that setting we obtain rather sharp estimates that are quite different from the scalar case, in both finite and infinite dimensional frameworks. The abstract theory applies, in particular, to dissipative wave, plate and beam equations
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
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