20 research outputs found
How Can Selection of Biologically Inspired Features Improve the Performance of a Robust Object Recognition Model?
Humans can effectively and swiftly recognize objects in complex natural scenes. This outstanding ability has motivated many computational object recognition models. Most of these models try to emulate the behavior of this remarkable system. The human visual system hierarchically recognizes objects in several processing stages. Along these stages a set of features with increasing complexity is extracted by different parts of visual system. Elementary features like bars and edges are processed in earlier levels of visual pathway and as far as one goes upper in this pathway more complex features will be spotted. It is an important interrogation in the field of visual processing to see which features of an object are selected and represented by the visual cortex. To address this issue, we extended a hierarchical model, which is motivated by biology, for different object recognition tasks. In this model, a set of object parts, named patches, extracted in the intermediate stages. These object parts are used for training procedure in the model and have an important role in object recognition. These patches are selected indiscriminately from different positions of an image and this can lead to the extraction of non-discriminating patches which eventually may reduce the performance. In the proposed model we used an evolutionary algorithm approach to select a set of informative patches. Our reported results indicate that these patches are more informative than usual random patches. We demonstrate the strength of the proposed model on a range of object recognition tasks. The proposed model outperforms the original model in diverse object recognition tasks. It can be seen from the experiments that selected features are generally particular parts of target images. Our results suggest that selected features which are parts of target objects provide an efficient set for robust object recognition
Brain tissue oxidative damage as a possible mechanism for the deleterious effect of a chronic high dose of estradiol on learning and memory in ovariectomized rats
Direct detection of photoinduced magnetic force at the nanoscale reveals magnetic nearfield of structured light
We demonstrate experimentally the detection of magnetic force at optical frequencies, defined as the dipolar Lorentz force exerted on a photoinduced magnetic dipole excited by the magnetic component of light. Historically, this magnetic force has been considered elusive since, at optical frequencies, magnetic effects are usually overshadowed by the interaction of the electric component of light, making it difficult to recognize the direct magnetic force from the dominant electric forces. To overcome this challenge, we develop a photoinduced magnetic force characterization method that exploits a magnetic nanoprobe under structured light illumination. This approach enables the direct detection of the magnetic force, revealing the magnetic nearfield distribution at the nanoscale, while maximally suppressing its electric counterpart. The proposed method opens up new avenues for nanoscopy based on optical magnetic contrast, offering a research tool for all-optical spin control and optomagnetic manipulation of matter at the nanoscale
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Use of the gamma probe to identify multigland disease in primary hyperparathyroidism
AimThe purpose of this study was to determine threshold gamma probe counts to distinguish single adenoma (SA) from multigland disease (MGD) during radioguided parathyroidectomy.MethodsA retrospective analysis of 1656 patients was performed. Ex vivo counts of the first excised gland were taken and recorded as a percentage of background counts.Results69.4% of MGD patients had counts below the 50% threshold. The 50% threshold correctly grouped 72.8% of our cohort. Counts of more than 100% were accurate for grouping SA, with only 6.8% of patients with counts more than 100% having MGD.ConclusionsThe gamma probe can aid surgeons in deciding to continue neck exploration if MGD is suspected or wait for labs to confirm cure if SA is suspected
Left-sided inferior vena cava implications for cardiopulmonary bypass cannulation in open thoracoabdominal aortic aneurysm repair
A left-sided inferior vena cava poses a unique challenge when cannulating for cardiopulmonary bypass during thoracoabdominal aortic aneurysm repair, and how to effectively and safely do so has not been previously described. A 51-year-old woman with a history of Loeys-Dietz syndrome and a left-sided inferior vena cava underwent open Crawford extent II thoracoabdominal aortic aneurysm repair. Cardiopulmonary bypass cannulation was performed using the right axillary artery, left common femoral artery, and right internal jugular vein. The patient's repair was successful, and she was ultimately discharged back to her home