60 research outputs found
Tools for Semi-automated Landform Classification: A Comparison in the Basilicata Region (Southern Italy)
Recent advances in spatial methods of digital elevation model
(DEMs) analysis have addressed many research topics on the assessment of
morphometric parameters of the landscape. Development of computer algorithms for calculating the geomorphometric properties of the Earth’s surface has
allowed for expanding of some methods in the semi-automatic recognition and
classification of landscape features. In such a way, several papers have been
produced, documenting the applicability of the landform classification based on
map algebra. The Topographic Position Index (TPI) is one of the most widely
used parameters for semi-automated landform classification using GIS software.
The aim was to apply the TPI classes for landform classification in the Basilicata
Region (Southern Italy). The Basilicata Region is characterized by an extremely
heterogeneous landscape and geological features. The automated landform
extraction, starting from two different resolution DEMs at 20 and 5 m-grids, has
been carried out by using three different GIS software: Arcview, Arcmap, and
SAGA. Comparison of the landform maps resulting from each software at a
different scale has been realized, furnishing at the end the best landform map and
consequently a discussion over which is the best software implementation of the
TPI method
Muscle variations and abnormal branching and course of the ulnar nerve in the forearm and hand
WOS: 000187803700013PubMed: 14695591During dissection of the right forearm of a 27-year-old female cadaver, variations in the form and insertion of the palmaris longus muscle were observed. The tendon of the palmaris longus muscle, which demonstrated a centrally placed belly, split into two tendons: one inserted into the palmar aponeurosis and the other into the proximal part of the flexor retinaculum. Additionally, we found an accessory muscle extending between the flexor retinaculum and the tendon of the abductor digiti minimi muscle. This accessory muscle was located deep to the ulnar artery but superficial to the superficial and deep branches of the ulnar nerve at the wrist. Finally, an aberrant branch of the ulnar nerve was identified in the forearm; it travelled distally alongside the ulnar artery and in the palm demonstrated communications with common palmar digital nerves from the ulnar and the median nerves. No variations were observed in the contralateral upper limb
A decision support system improves the interpretation of myocardial perfusion imaging
PURPOSE: The aim of this study was to investigate the influence of a computer-based decision support system (DSS) on performance and inter-observer variability of interpretations regarding ischaemia and infarction in myocardial perfusion scintigraphy (MPS). METHODS: Seven physicians independently interpreted 97 MPS studies, first without and then with the advice of a DSS. Four physicians had long experience and three had limited experience in the interpretation of MPS. Each study was interpreted regarding myocardial ischaemia and infarction in five myocardial regions. The patients had undergone a gated MPS using a 2-day stress/gated rest (99m)Tc sestamibi protocol. The gold standard used was the interpretations made by one experienced nuclear medicine specialist on the basis of all available clinical and image information. RESULTS: The sensitivity for ischaemia of the seven readers increased from 81% without the DSS to 86% with the DSS (p = 0.01). The increase in sensitivity was higher for the three inexperienced physicians (9%) than for the four experienced physicians (2%). There was no significant change in specificity between the interpretations. The interpretations of ischaemia made with the advice of the DSS showed less inter-observer variability than those made without advice. CONCLUSION: This study shows that a DSS can improve performance and reduces the inter-observer variability of interpretations in myocardial perfusion imaging. Both experienced and, especially, inexperienced physicians can improve their interpretation with the advice from such a system
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