8,721 research outputs found
Case report. A rare case of giant basal cell carcinoma and malignant melanoma
The presence of two several skin lesions in the same patient is a rare occurrence in dermatological findings. The associations of malignant melanoma (MM) and giant basal cell carcinoma (BCC) within the same patient have only been described in few cases in the literature.1,6 Is there a common genetic origin? However, until now the pathogenesis of collision tumors existing of MM and BCC remains unclear. We, therefore, report a case of association of MM and BCC in the same patient
Dynamics in the Fitness-Income plane: Brazilian states vs World countries
In this paper we introduce a novel algorithm, called Exogenous Fitness, to calculate the Fitness of subnational entities and we apply it to the states of Brazil. In the last decade, several indices were introduced to measure the competitiveness of countries by looking at the complexity of their export basket. Tacchella et al (2012) developed a non-monetary metric called Fitness. In this paper, after an overview about Brazil as a whole and the comparison with the other BRIC countries, we introduce a new methodology based on the Fitness algorithm, called Exogenous Fitness. Combining the results with the Gross Domestic Product per capita (GDPp), we look at the dynamics of the Brazilian states in the Fitness-Income plane. Two regimes are distinguishable: one with high predictability and the other with low predictability, showing a deep analogy with the heterogeneous dynamics of the World countries. Furthermore, we compare the ranking of the Brazilian states according to the Exogenous Fitness with the ranking obtained through two other techniques, namely Endogenous Fitness and Economic Complexity Index
A rare case of leiomyoma of the bladder
Bladder leiomyoma is a benign tumour of the bladder and constitute <0.5% of all bladder tumors. We report a clinical case of a 51‑year‑old female who presented with with symptomatic bladder leiomyoma. An ultrasound examination showed well-defined bladder leiomyoma in the right posterior bladder wall, which was excised through a transurethral resection. The pathologic diagnosis was bladder leiomyoma
Patient-specific 3D Printed Liver Models for Pre-operative Planning and Improved Patient Adherence
Project Background: 3D anatomical relationships in the liver are not always visually accessible for surgeons performing resections even with advanced imaging options. Firm understanding of these relationships is essential for timely procedures, which can improve patient outcomes and lower hospital expenses. Patient-specific 3D modeling has existed for some time, though it is costly. New cost-effective techniques have surfaced which may yield opportunities for more effective preoperative planning in liver surgery and improved patient adherence.
Methods: Digital patient-specific 3D reconstruction of a liver was completed by interpolating data from MRI scans using 3D Slicer, a segmenting program. The liver model was processed and 3D printed as a shell to be used as a mold. The liver shell, associated vasculature, and tumor were printed using polylactic acid (PLA) filament on an Ultimaker S5 3D printer. Transparent silicone was used as a cast, giving the model a solid form yet still allowing examination of the inside contents.
Results: One completed liver model was used in pre-surgical consultation of a patient with hepatocellular carcinoma undergoing liver resection and during the surgical procedure as a guide for the surgical team. A follow-up survey concerning qualitative aspects of the model administered to the surgical team suggested high accuracy of the model compared to the anatomy observed during the procedure.
Conclusion: Cost-effective techniques in producing patient specific 3D anatomical models appears not only feasible, but highly effective in improving communication between the surgical team during the procedure and also between the surgeon and the patient during pre-surgical consultation. Future research may be conducted concerning the model’s visual clarity as well as impact on patient adherence post-op
Regional prediction of basin-scale brown trout habitat suitability
Abstract. In this study we propose a novel method for the estimation of ecological indices describing the habitat suitability of brown trout (Salmo trutta). Traditional hydrological tools are coupled with an innovative regional geostatistical technique, aiming at the prediction of the brown trout habitat suitability index where partial or totally ungauged conditions occur. Several methods for the assessment of ecological indices are already proposed in the scientific literature, but the possibility of exploiting a geostatistical prediction model, such as Topological Kriging, has never been investigated before. In order to develop a regional habitat suitability model we use the habitat suitability curve, obtained from measured data of brown trout adult individuals collected in several river basins across the USA. The Top-kriging prediction model is then employed to assess the spatial correlation between upstream and downstream habitat suitability indices. The study area is the Metauro River basin, located in the central part of Italy (Marche region), for which both water depth and streamflow data were collected. The present analysis focuses on discharge values corresponding to the 0.1-, 0.5-, 0.9-empirical quantiles derived from flow-duration curves available for seven gauging stations located within the study area, for which three different suitability indices (i.e. ψ10, ψ50 and ψ90) are evaluated. The results of this preliminary analysis are encouraging showing Nash-Sutcliffe efficiencies equal to 0.52, 0.65, and 0.69, respectively
Circular motion of neutral test particles in Reissner-Nordstr\"om spacetime
We investigate the motion of neutral test particles in the gravitational
field of a mass with charge described by the Reissner-Nordstr\"om (RN)
spacetime. We focus on the study of circular stable and unstable orbits around
configurations describing either black holes or naked singularities. We show
that at the classical radius, defined as , there exist orbits with zero
angular momentum due to the presence of repulsive gravity. The analysis of the
stability of circular orbits indicates that black holes are characterized by a
continuous region of stability. In the case of naked singularities, the region
of stability can split into two non-connected regions inside which test
particles move along stable circular orbits.Comment: 23 pages, 22 figures. To be published Phys. Rev.
Modelling of integrated-light spectra from the optical to the near-infrared: the globular cluster G280 in M31
In previous papers, we introduced our method for measuring chemical
abundances from integrated-light spectra of globular clusters and applied it to
a variety of extragalactic star clusters. Here we extend our analysis technique
to the infrared. We simultaneously analyse an optical spectrum of the massive
globular cluster G280 in M31, obtained with the HIRES spectrograph on the Keck
I telescope, and an H-band spectrum obtained with NIRSPEC on Keck II. We
discuss the sensitivity of our results to various modifications of the input
assumptions, such as different line lists and isochrones and the possible
presence of a metallicity spread in G280. When using the most recent version of
the Kurucz line list, we measure iron abundances of [Fe/H]=-0.68+/-0.02 from
the optical spectrum and [Fe/H]=-0.60+/-0.07 from the infrared spectrum. These
values agree well with previous spectroscopic determinations of the metallicity
of G280. While the small difference between the optical and infrared
measurements is insignificant given the uncertainties, it is also consistent
with a metallicity spread similar to that observed in massive GCs such as Omega
Cen and G1, and also hinted at by the colour-magnitude diagram of G280. The
optical and infrared spectra both indicate an alpha-enhancement of about
0.3-0.4 dex relative to solar-scaled abundances, as typically also observed in
Milky Way GCs. It appears that our integrated-light analysis technique also
performs well in the H-band. However, complications due to the presence of
molecular bands and telluric contamination are more severe in the infrared, and
accurate modelling of the coolest giants is more critical.Comment: Accepted for publication in Astronomy & Astrophysic
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