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IEEE Transactions on Image Processing :... 2022Fine-grained image hashing is challenging due to the difficulties of capturing discriminative local information to generate hash codes. On the one hand, existing methods...
Fine-grained image hashing is challenging due to the difficulties of capturing discriminative local information to generate hash codes. On the one hand, existing methods usually extract local features with the dense attention mechanism by focusing on dense local regions, which cannot contain diverse local information for fine-grained hashing. On the other hand, hash codes of the same class suffer from large intra-class variation of fine-grained images. To address the above problems, this work proposes a novel sub-Region Localized Hashing (sRLH) to learn intra-class compact and inter-class separable hash codes that also contain diverse subtle local information for efficient fine-grained image retrieval. Specifically, to localize diverse local regions, a sub-region localization module is developed to learn discriminative local features by locating the peaks of non-overlap sub-regions in the feature map. Different from localizing dense local regions, these peaks can guide the sub-region localization module to capture multifarious local discriminative information by paying close attention to dispersive local regions. To mitigate intra-class variations, hash codes of the same class are enforced to approach one common binary center. Meanwhile, the gram-schmidt orthogonalization is performed on the binary centers to make the hash codes inter-class separable. Extensive experimental results on four widely used fine-grained image retrieval datasets demonstrate the superiority of sRLH to several state-of-the-art methods. The source code of sRLH will be released at https://github.com/ZhangYajie-NJUST/sRLH.git.
PubMed: 34871171
DOI: 10.1109/TIP.2021.3131042 -
Journal of Cardiovascular... Nov 2019The major sites of origins of idiopathic ventricular arrhythmias have been elucidated. Idiopathic ventricular arrhythmias most often present as premature ventricular... (Review)
Review
The major sites of origins of idiopathic ventricular arrhythmias have been elucidated. Idiopathic ventricular arrhythmias most often present as premature ventricular contractions (PVCs) with a focal mechanism, and commonly occur without structural heart disease. Idiopathic ventricular arrhythmias usually originate from specific anatomical structures, commonly endocardial but sometimes epicardial and exhibit characteristic electrocardiograms (ECGs) based on their anatomical background. There are general and specific ECG characteristics that can localize the site of idiopathic PVC origins. The general ECG characteristics include the bundle branch block pattern, axis, QRS polarity in lead V6, QRS duration, precordial transition, maximal deflection index, and so forth. They can roughly localize the site of idiopathic PVC origins. Several major sites of idiopathic PVC origins are located close to each other, and specific ECG characteristics are helpful for localizing the site of origins more accurately in those PVCs. Twelve-lead surface ECG algorithms usually can localize the site of idiopathic PVC origins with a high accuracy, but their accuracy can be limited by the patients' physique, heart rotation, specific conduction properties, presence of structural heart disease, and so forth. This review describes an overview of the approaches to the 12-lead surface ECG localization of idiopathic PVCs, and also discusses their caveats and limitations.
Topics: Electrocardiography; Electrodes; Heart Rate; Humans; Tomography, X-Ray Computed; Ventricular Premature Complexes
PubMed: 31502322
DOI: 10.1111/jce.14152 -
Epilepsy & Behavior Case Reports 2017To investigate the probable ictal origin of unexplained episodic chest pain and if possible to lateralize and localize the epileptic focus.
PURPOSE
To investigate the probable ictal origin of unexplained episodic chest pain and if possible to lateralize and localize the epileptic focus.
METHODS
A 14 year old boy presented with episodic short lasting localized chest pain. His cardiac and other systemic work-up were normal. MRI brain did not reveal any structural pathology. Video telemetry was done for characterization of the paroxysms.
RESULTS
Interictal record showed left fronto-central epileptiform discharges. A left hemispheric, predominantly centroparietal ictal rhythm was identified. The possible localizations of this unusual semiology are somatosensory areas I and II, supplementary sensorimotor area, posterior insula and cingulate cortex. Patient responded remarkably to antiseizure drugs.
CONCLUSION
Pain is a rare manifestation of epilepsy observed in less than 1% of patients. When present, it is usually accompanied by other focal features. This rare occurrence of epileptic seizures masquerading as angina is a novel observation.
PubMed: 28393015
DOI: 10.1016/j.ebcr.2017.02.001 -
Continuum (Minneapolis, Minn.) Oct 2014The main objective of this article is to offer a regional approach to brachial plexus assessment because, although the brachial plexus is the largest and most complex... (Review)
Review
PURPOSE OF REVIEW
The main objective of this article is to offer a regional approach to brachial plexus assessment because, although the brachial plexus is the largest and most complex peripheral nervous system structure, most of its disorders involve only a portion of it. Consequently, regional assessment typically localizes and characterizes the lesion.
RECENT FINDINGS
The sensory axons traversing each region are known and provide localizing information.
SUMMARY
Because localization dictates the differential diagnosis and the resulting initial clinical management, examining physicians must first localize the lesion. Localization of a brachial plexus lesion requires an appreciation of brachial plexus anatomy, lesion classification, and the routes traversed by the various axons composing the brachial plexus, especially the sensory axons. This information is reviewed in this article and followed by discussions of several brachial plexus disorders, especially those with regional predilections.
Topics: Adolescent; Brachial Plexus Neuropathies; Humans; Male; Middle Aged; Young Adult
PubMed: 25299285
DOI: 10.1212/01.CON.0000455878.60932.37 -
Frontiers in Plant Science 2018Plastids in the viridiplantae sporadically form thin tubules called stromules that increase the interactive surface between the plastid and the surrounding cytoplasm....
UNLABELLED
Plastids in the viridiplantae sporadically form thin tubules called stromules that increase the interactive surface between the plastid and the surrounding cytoplasm. Several recent publications that report observations of certain proteins localizing to the extensions have then used the observations to suggest stromule-specific functions. The mechanisms by which specific localizations on these transient and sporadically formed extensions might occur remain unclear. Previous studies have yet to address the spatiotemporal relationship between a particular protein localization pattern and its distribution on an extended stromules and/or the plastid body. Here, we have used discrete protein patches found in several transgenic plants as fiducial markers to investigate this relationship. While we consider the inner plastid envelope-membrane localized protein patches of the GLUCOSE 6-PHOSPHATE/PHOSPHATE TRANSLOCATOR1 and the TRIOSE-PHOSPHATE/ PHOSPHATE TRANSLOCATOR 1 as artifacts of fluorescent fusion protein over-expression, stromule formation is not compromised in the respective stable transgenic lines that maintain normal growth and development. Our analysis of chloroplasts in the transgenic lines in the Arabidopsis Columbia background, and in the mutant, under stromule-inducing conditions shows that the possibility of finding a particular protein-enriched domain on an extended stromule or on a region of the main plastid body is stochastic. Our observations provide insights on the behavior of chloroplasts, the relationship between stromules and the plastid-body and strongly challenge claims of stromule-specific functions based solely upon protein localization to plastid extensions.
ONE SENTENCE SUMMARY
Observations of the spatiotemporal relationship between plastid envelope localized fluorescent protein fusions of two sugar-phosphate transporters and stromules suggest a stochastic rather than specific localization pattern that questions the idea of independent functions for stromules.
PubMed: 29915611
DOI: 10.3389/fpls.2018.00754 -
American Journal of Neurodegenerative... 2021The prevalence of neurodegenerative diseases is accelerating in rapidly aging global population. Novel and effective diagnostic and therapeutic methods are required to... (Review)
Review
The prevalence of neurodegenerative diseases is accelerating in rapidly aging global population. Novel and effective diagnostic and therapeutic methods are required to tackle the global issue of neurodegeneration in the future. A better understanding of the potential molecular mechanism causing neurodegeneration can shed light on dysfunctional processes in diseased neurons, which can pave the way to design and synthesize novel targets for early diagnosis during the asymptomatic phase of the disease. Abnormal protein aggregation is a hallmark of neurodegenerative diseases which can hamper transportation of cargoes into axons. Recent evidence suggests that disruption of local protein synthesis has been observed in neurodegenerative diseases. Because of their highly asymmetric structure, highly polarized neurons require trafficking of cargoes from the cell body to different subcellular regions to meet the extensive demands of cellular physiology. Localization of mRNAs and subsequent local translation to corresponding proteins in axons is a mechanism which allows neurons to rapidly respond to external stimuli as well as establishing neuronal networks by synthesizing proteins on demand. Axonal protein synthesis is required for axon guidance, synapse formation and plasticity, axon maintenance and regeneration in response to injury. Different types of excitatory and inhibitory neurons in the central and peripheral nervous systems have been shown to localize mRNA. Rising evidence suggests that the repertoire of localizing mRNA in axons can change during aging, indicating a connection between axonal mRNA trafficking and aging diseases such as neurodegeneration. Here, I briefly review the latest findings on the importance of mRNA localization and local translation in neurons and the consequences of their disruption in neurodegenerative diseases. In addition, I discuss recent evidence that dysregulation of mRNA localization and local protein translation can contribute to the formation of neurodegenerative diseases such as Alzheimer's disease, Amyotrophic Lateral Sclerosis, and Spinal Muscular Atrophy. In addition, I discuss recent findings on mRNAs localizing to mitochondria in neurodegeneration.
PubMed: 33815964
DOI: No ID Found -
Continuum (Minneapolis, Minn.) Feb 2016Focal epilepsy is the most common type of epilepsy in adulthood. This article discusses the seizure symptomatology, EEG findings, and imaging findings of the various... (Review)
Review
PURPOSE OF REVIEW
Focal epilepsy is the most common type of epilepsy in adulthood. This article discusses the seizure symptomatology, EEG findings, and imaging findings of the various forms of focal epilepsy. The majority of the article focuses on temporal and frontal lobe epilepsy as these represent the majority of focal epilepsies.
RECENT FINDINGS
While significant overlap exists in the clinical symptomatology of the focal epilepsies, detailed seizure descriptions can often provide useful clinical evidence to help establish an accurate diagnosis. EEG and MRI continue to serve as the main diagnostic tools for the diagnosis of focal epilepsy.
SUMMARY
The various forms of focal epilepsy generate seizure presentations that are dependent on the anatomic structures that are involved in the seizure. By understanding the symptoms typically generated in each region of the brain, a better understanding of the possible seizure localizations can be made. Most forms of epilepsy have clear changes on EEG that permit accurate localization, but several pitfalls exist, which are discussed in this article. Imaging has revolutionized our ability to accurately identify lesions associated with epilepsy and increased our ability to localize seizures in the brain.
Topics: Adult; Electroencephalography; Epilepsies, Partial; Female; Humans; Male
PubMed: 26844732
DOI: 10.1212/CON.0000000000000290 -
Current Neurology and Neuroscience... Feb 2024Magnetoencephalography (MEG) is a functional neuroimaging technique that records neurophysiology data with millisecond temporal resolution and localizes it with... (Review)
Review
PURPOSE OF THE REVIEW
Magnetoencephalography (MEG) is a functional neuroimaging technique that records neurophysiology data with millisecond temporal resolution and localizes it with subcentimeter accuracy. Its capability to provide high resolution in both of these domains makes it a powerful tool both in basic neuroscience as well as clinical applications. In neurology, it has proven useful in its ability to record and localize epileptiform activity. Epilepsy workup typically begins with scalp electroencephalography (EEG), but in many situations, EEG-based localization of the epileptogenic zone is inadequate. The complementary sensitivity of MEG can be crucial in such cases, and MEG has been adopted at many centers as an important resource in building a surgical hypothesis. In this paper, we review recent work evaluating the extent of MEG influence of presurgical evaluations, novel analyses of MEG data employed in surgical workup, and new MEG instrumentation that will likely affect the field of clinical MEG.
RECENT FINDINGS
MEG consistently contributes to presurgical evaluation and these contributions often change the plan for epilepsy surgery. Extensive work has been done to develop new analytic methods for localizing the source of epileptiform activity with MEG. Systems using optically pumped magnetometry (OPM) have been successfully deployed to record and localize epileptiform activity. MEG remains an important noninvasive tool for epilepsy presurgical evaluation. Continued improvements in analytic methodology will likely increase the diagnostic yield of the test. Novel instrumentation with OPM may contribute to this as well, and may increase accessibility of MEG by decreasing cost.
Topics: Humans; Magnetoencephalography; Epilepsy; Electroencephalography; Neuroimaging; Functional Neuroimaging
PubMed: 38148387
DOI: 10.1007/s11910-023-01328-5 -
AIMS Neuroscience 2020The spatial and temporal regulation of gene expression in neurons is an important step in creating functional and structural neuronal networks. The complexity of neurons... (Review)
Review
The spatial and temporal regulation of gene expression in neurons is an important step in creating functional and structural neuronal networks. The complexity of neurons require differential expression of various proteins in different compartments. Highly polarised cells, such as neurons, respond rapidly to different external stimuli by changing their local protein abundance and composition. Neurons can have extensions up to a meter away from their cell body in humans, so it is easy to envisage why they need to manage the synthesis of new proteins locally and on-demand. Recent research has demonstrated that neurons can control the expression of different proteins by localising translationally silent mRNAs, followed by subsequent translation. Neurons use mRNA localization and local translation to achieve different purposes during their life cycle. While developing neurons rely on mRNA localization for axon guidance and synaptogenesis, mature neurons can use mRNA localization for maintenance of essential physiological processes. mRNA localization also plays a role in response to neuron injury to regenerate and restore neuronal connections. Recent microscopic imaging techniques such as live imaging of fluorescently tagged molecules combined with genetic and biochemical studies in neurons have illustrated evolutionarily conserved mechanisms for targeting mRNAs into their correct compartments. This review provides an overview of mRNA localization and local translation in vertebrate and invertebrate neurons and discusses the mechanism by which mRNAs are trafficked into axons. Furthermore, the role of mRNA localization in synaptic activation, as well as axonal injury is explored.
PubMed: 32995487
DOI: 10.3934/Neuroscience.2020016 -
The Journal of the Acoustical Society... Aug 2021Localizing and tracking an underwater acoustic source is a key task for maritime situational awareness. This paper presents a sequential Bayesian estimation method for...
Localizing and tracking an underwater acoustic source is a key task for maritime situational awareness. This paper presents a sequential Bayesian estimation method for passive acoustic source localization in shallow water. The proposed probabilistic focalization approach associates detected directions of arrival (DOAs) to modeled DOAs and jointly estimates the time-varying source location. Embedded ray tracing makes it possible to incorporate environmental parameters that characterize the acoustic waveguide. Due to its statistical model, the proposed method can provide robustness in scenarios with severe environmental uncertainty. We demonstrate performance advantages compared to matched field processing using data collected during the SWellEx-96 experiment.
PubMed: 34470313
DOI: 10.1121/10.0005814