We present different constructions of abstract boundaries for bounded complete (Kobayashi) hyperbolic domains in ℂ
d
,
d
≥ 1. These constructions essentially come from the geometric theory of metric ...spaces. We also present, as an application, some extension results concerning biholomorphic maps.
CHALLENGES IN FUSION OF HETEROGENEOUS POINT CLOUDS Bracci, F.; Drauschke, M.; Kühne, S. ...
International archives of the photogrammetry, remote sensing and spatial information sciences.,
05/2018, Letnik:
XLII-2
Journal Article
Recenzirano
Odprti dostop
Different platforms and sensors are used to derive 3d models of urban scenes. 3d reconstruction from satellite and aerial images are used to derive sparse models mainly showing ground and roof ...surfaces of entire cities. In contrast to such sparse models, 3d reconstructions from UAV or ground images are much denser and show building facades and street furniture as traffic signs and garbage bins. Furthermore, point clouds may also get acquired with LiDAR sensors. Point clouds do not only differ in the viewpoints, but also in their scales and point densities. Consequently, the fusion of such heterogeneous point clouds is highly challenging. Regarding urban scenes, another challenge is the occurence of only a few parallel planes where it is difficult to find the correct rotation parameters. We discuss the limitations of the general fusion methodology based on an initial alignment step followed by a local coregistration using ICP and present strategies to overcome them.
Background:
Some reports highlight the potential application of fecal calprotectin as a direct biomarker of intestinal inflammation and, therefore, as support in choosing candidates for endoscopy. ...The value of 100 μg/g was recently assumed as the best cutoff for this assay. The purpose of this study was to assess the diagnostic precision of the fecal calprotectin assay, compared to histology, as a stool‐screening biomarker for inflammatory bowel disease (IBD) among a group of prospectively identified patients referred for recurrent abdominal pain and altered bowel habits.
Methods:
Between 1999 and 2007 we prospectively evaluated the calprotectin assay in a cohort of patients with recurrent abdominal pain and altered bowel habits associated or not with other symptoms suggestive of IBD. All patients suspected of IBD, according to Rome and Porto criteria, provided stool specimens for the calprotectin assay and subsequently underwent endoscopic procedures.
Results:
Compared to histology, the cutoff of 100 μg/g reached a sensitivity and specificity of 100% and 68%, respectively, and a likelihood ratio (LR) of 3.1. The cutoff value of 160 μg/g, however, in our series produced the best joint estimate of sensitivity and specificity: 100% and 80%, respectively, with an LR of 5.
Conclusions:
In pediatric patients with recurrent abdominal pain and changes in stool habits, a positive calprotectin assay is closely associated with IBD; its systematic employment, therefore, seems to improve the process of endoscopy referral. This test, simple and inexpensive, could be included in the first noninvasive phase of an IBD diagnostic work‐up. (Inflamm Bowel Dis 2010)
Primary lactase deficiency (PLD) is a common inherited condition caused by a reduced activity of lactase. Two single-nucleotide polymorphisms C/T(-13910) and G/A(-22018) upstream of the lactase gene ...are associated with lactase nonpersistence. In celiac disease (CD) patients, lactose intolerance could be due to secondary lactase deficiency and to PLD. The aim of this study were to evaluate the association of PLD and CD using genetic test, and to define the prevalence of PLD in celiac subjects compared with a control population. A total of 188 controls and 92 biopsy-proven CD patients were included in the study. More than 70% of all subjects were found homozygous for the polymorphisms. Differences in the prevalence of PLD were not found between CD patients and controls.In conclusions, the hereditary lactase deficiency is frequent in Italian CD children as in control population.
Background: Inflammatory bowel diseases (IBD) are characterized by periods of remission with recurrent episodes of symptom exacerbation because of acute intestinal inflammation, which is correctly ...evaluated by endoscopy with biopsy sampling. However, many surrogate markers of intestinal inflammation, including fecal calprotectin (FC), are detected as potential predictors of mucosal inflammation in IBD patients. The aim of our study was to retrospectively assess the clinical efficacy of the calprotectin assay in determining histological relapses of pediatric IBD patients.
Methods: We retrospectively reviewed the histological examinations, clinical records, and FC values of patients who had undergone colonoscopy at our hospital over an 8‐year period, from December 31, 1998, to December 31, 2006. Only patients with a first histological examination showing a quiescent IBD who submitted to a second histological examination during the next 3 years were selected.
Results: Seventy‐three IBD patients, all with a first biopsy showing a quiescent IBD, were studied; at the second histological examination, 32 presented with relapse and 41 presented with remission. Relapsed patients showed significantly increased FC levels compared with nonrelapsed patients. A FC value of 275 μg/g achieved sensitivity and negative predictive value of 97% and specificity and positive predictive value of 85% in predicting histological relapse.
Conclusions: FC seems to be a direct measure of intestinal inflammation and therefore a good marker of the risk of histological relapse in pediatric IBD patients. The application of this test in clinical practice may enable the avoidance of invasive tests as well as targeting treatment.
(Inflamm Bowel Dis 2008)
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