Search results for "landmark"

Anatomic and flow dynamic considerations for safe right axillary artery cannulation.

2013

Objectives Neuroprotection is of paramount interest in cardiac surgery. Right axillary artery cannulation is well established in aortic surgery because it significantly improves survival and outcome, but malperfusion of the right brain after direct cannulation has been reported. Anatomically, 4 vessel segments are potentially amenable for cannulation of the subclavian and axillary arteries. Clinical studies vary widely in dissection sites and cannulation techniques. We investigated critical flow dynamics in the right brain caused by arterial inflow after direct cannulation and specified cannulation positions that provide optimal cerebral perfusion. Methods Distances from the lateral margin …

Modeling retinal landmarks for medical diagnosis automatization

Human Visual Perception and Retinal Diseases

2010

Retinal diseases are causing alterations of the visual perception leading sometimes to blindness. For this reason, early detection and diagnosis of retinal pathologies is very important. Using digital image processing techniques, retinal images may be analyzed quickly and computer-assisted diagnosis systems may be developed in order to help the ophthalmologists to make a diagnosis. In this paper we described shortly two computer-assisted systems for the detection of retinal landmarks (optic disc and vasculature) together with a brief introduction to the human visual system and to some alterations of the visual perception caused by retinal diseases.

Contatti culturali, identità e popolamento nel territorio imerese

2016

Il lavoro prende in considerazione il problema dei rapporti tra coloni greci e comunità indigene nel territorio di Himera, sulla base dei risultati della prospezione archeologica condotta per tre decenni nelle valli dei fiumi Imera settentrionale, Torto e S. Leonardo. Vengono esaminati gli elementi di cultura materiale che permettono di definire i modi dell'interazione culturale tra coloni e indigeni, nonché di ricostruire i paesaggi politici, socio-economici e il paesaggio del sacro nelle diverse aree indagate e nei diversi comprensori. La ricerca infatti permette di delineare, oltre alle usuali organizzazioni insediative e agricole della chora politiké e della éremos chora, anche articola…

Attention-Based Landmark Selection in Autonomous Robotics

2007

This paper describes a robotic architecture that uses visual attention mechanisms for autonomous navigation in unknown indoor environments. A foveation mechanism based on a bottom-up attention system allows the robot to autonomously select landmarks, defined as salient points in the camera images. Landmarks are memorized in a behavioral fashion by coupling sensing and acting to achieve a representation that is view and scale independent. Selected landmarks are stored in a topological map. During the navigation a top-down mechanism controls the attention system to achieve robot localization. Experiments and results show that our system is robust to noise and odometric errors, being at the sa…

Honeybees can recognise images of complex natural scenes for use as potential landmarks

2008

SUMMARY The ability to navigate long distances to find rewarding flowers and return home is a key factor in the survival of honeybees (Apis mellifera). To reliably perform this task, bees combine both odometric and landmark cues,which potentially creates a dilemma since environments rich in odometric cues might be poor in salient landmark cues, and vice versa. In the present study, honeybees were provided with differential conditioning to images of complex natural scenes, in order to determine if they could reliably learn to discriminate between very similar scenes, and to recognise a learnt scene from a novel distractor scene. Choices made by individual bees were modelled with signal detec…

Interstitial Telomeric-like Repeats (ITR) in Seed Plants as Assessed by Molecular Cytogenetic Techniques: A Review.

2021

The discovery of telomeric repeats in interstitial regions of plant chromosomes (ITRs) through molecular cytogenetic techniques was achieved several decades ago. However, the information is scattered and has not been critically evaluated from an evolutionary perspective. Based on the analysis of currently available data, it is shown that ITRs are widespread in major evolutionary lineages sampled. However, their presence has been detected in only 45.6% of the analysed families, 26.7% of the sampled genera, and in 23.8% of the studied species. The number of ITR sites greatly varies among congeneric species and higher taxonomic units, and range from one to 72 signals. ITR signals mostly occurs…

Surgical anatomy of the deep postanal space and the re-modified Hanley procedure - a video vignette.

2018

An 'easy' method to understand perianal sepsis - a video vignette.

2019

Infraclavicular access to the axillary vein-new possibilities for the catheterization of the central veins in the intensive care unit

2016

Central vein cannulation is one of the most commonly performed procedures in intensive care. Traditionally, the jugular and subclavian vein are recommended as the first choice option. Nevertheless, these attempts are not always obtainable for critically ill patients. For this reason, the axillary vein seems to be a rational alternative approach. In this narrative review, we evaluate the usefulness of the infraclavicular access to the axillary vein. The existing evidence suggests that infraclavicular approach to the axillary vein is a reliable method of central vein catheterization, especially when performed with ultrasound guidance.