65 research outputs found
Deep Learning in Cardiology
The medical field is creating large amount of data that physicians are unable
to decipher and use efficiently. Moreover, rule-based expert systems are
inefficient in solving complicated medical tasks or for creating insights using
big data. Deep learning has emerged as a more accurate and effective technology
in a wide range of medical problems such as diagnosis, prediction and
intervention. Deep learning is a representation learning method that consists
of layers that transform the data non-linearly, thus, revealing hierarchical
relationships and structures. In this review we survey deep learning
application papers that use structured data, signal and imaging modalities from
cardiology. We discuss the advantages and limitations of applying deep learning
in cardiology that also apply in medicine in general, while proposing certain
directions as the most viable for clinical use.Comment: 27 pages, 2 figures, 10 table
Signal2Image Modules in Deep Neural Networks for EEG Classification
Deep learning has revolutionized computer vision utilizing the increased
availability of big data and the power of parallel computational units such as
graphical processing units. The vast majority of deep learning research is
conducted using images as training data, however the biomedical domain is rich
in physiological signals that are used for diagnosis and prediction problems.
It is still an open research question how to best utilize signals to train deep
neural networks.
In this paper we define the term Signal2Image (S2Is) as trainable or
non-trainable prefix modules that convert signals, such as
Electroencephalography (EEG), to image-like representations making them
suitable for training image-based deep neural networks defined as `base
models'. We compare the accuracy and time performance of four S2Is (`signal as
image', spectrogram, one and two layer Convolutional Neural Networks (CNNs))
combined with a set of `base models' (LeNet, AlexNet, VGGnet, ResNet, DenseNet)
along with the depth-wise and 1D variations of the latter. We also provide
empirical evidence that the one layer CNN S2I performs better in eleven out of
fifteen tested models than non-trainable S2Is for classifying EEG signals and
we present visual comparisons of the outputs of the S2Is.Comment: 4 pages, 2 figures, 1 table, EMBC 201
Sparsely Activated Networks
Previous literature on unsupervised learning focused on designing structural
priors with the aim of learning meaningful features. However, this was done
without considering the description length of the learned representations which
is a direct and unbiased measure of the model complexity. In this paper, first
we introduce the metric that evaluates unsupervised models based on
their reconstruction accuracy and the degree of compression of their internal
representations. We then present and define two activation functions (Identity,
ReLU) as base of reference and three sparse activation functions (top-k
absolutes, Extrema-Pool indices, Extrema) as candidate structures that minimize
the previously defined . We lastly present Sparsely Activated Networks
(SANs) that consist of kernels with shared weights that, during encoding, are
convolved with the input and then passed through a sparse activation function.
During decoding, the same weights are convolved with the sparse activation map
and subsequently the partial reconstructions from each weight are summed to
reconstruct the input. We compare SANs using the five previously defined
activation functions on a variety of datasets (Physionet, UCI-epilepsy, MNIST,
FMNIST) and show that models that are selected using have small
description representation length and consist of interpretable kernels.Comment: 10 pages, 5 figures, 4 algorithms, 4 tables, submission to IEEE
Transactions on Neural Networks and Learning System
3-D Registration on Carotid Artery imaging data: MRI for different timesteps
A common problem which is faced by the researchers when dealing with arterial
carotid imaging data is the registration of the geometrical structures between
different imaging modalities or different timesteps. The use of the "Patient
Position" DICOM field is not adequate to achieve accurate results due to the
fact that the carotid artery is a relatively small structure and even
imperceptible changes in patient position and/or direction make it difficult.
While there is a wide range of simple/advanced registration techniques in the
literature, there is a considerable number of studies which address the
geometrical structure of the carotid artery without using any registration
technique. On the other hand the existence of various registration techniques
prohibits an objective comparison of the results using different registration
techniques. In this paper we present a method for estimating the statistical
significance that the choice of the registration technique has on the carotid
geometry. One-Way Analysis of Variance(ANOVA) showed that the p-values were
<0.0001 for the distances of the lumen from the centerline for both right and
left carotids of the patient case that was studied.Comment: 4 pages, 4 figures, 1 table, preprint submitted to IEEE-EMBC 201
A feasibility study for the provision of electronic healthcare tools and services in areas of Greece, Cyprus and Italy
Background:
Through this paper, we present the initial steps for the creation of an integrated platform for the provision of a series of eHealth tools and services to both citizens and travelers in isolated areas of thesoutheast Mediterranean, and on board ships travelling across it. The platform was created through an INTERREG IIIB ARCHIMED project called INTERMED.
Methods:
The support of primary healthcare, home care and the continuous education of physicians are the three major issues that the proposed platform is trying to facilitate. The proposed system is based on state-of-the-art telemedicine systems and is able to provide the following healthcare services: i) Telecollaboration and teleconsultation services between remotely located healthcare providers, ii) telemedicine services in emergencies, iii) home telecare services for "at risk" citizens such as the elderly and patients with chronic diseases, and iv) eLearning services for the continuous training through seminars of both healthcare personnel (physicians, nurses etc) and persons supporting "at risk" citizens.
These systems support data transmission over simple phone lines, internet connections, integrated services digital network/digital subscriber lines, satellite links, mobile networks (GPRS/3G), and wireless local area networks. The data corresponds, among others, to voice, vital biosignals, still medical images, video, and data used by eLearning applications. The proposed platform comprises several systems, each supporting different services. These were integrated using a common data storage and exchange scheme in order to achieve system interoperability in terms of software, language and national characteristics.
Results:
The platform has been installed and evaluated in different rural and urban sites in Greece, Cyprus and Italy. The evaluation was mainly related to technical issues and user satisfaction. The selected sites are, among others, rural health centers, ambulances, homes of "at-risk" citizens, and a ferry.
Conclusions:
The results proved the functionality and utilization of the platform in various rural places in Greece, Cyprus and Italy. However, further actions are needed to enable the local healthcare systems and the different population groups to be familiarized with, and use in their everyday lives, mature technological solutions for the provision of healthcare services
Gravitational Influence on Human Living Systems and the Evolution of Species on Earth
Gravity constituted the only constant environmental parameter, during the evolutionary period of living matter on Earth. However, whether gravity has affected the evolution of species, and its impact is still ongoing. The topic has not been investigated in depth, as this would require frequent and long-term experimentations in space or an environment of altered gravity. In addition, each organism should be studied throughout numerous generations to determine the profound biological changes in evolution. Here, we review the significant abnormalities presented in the cardiovascular, immune, vestibular and musculoskeletal systems, due to altered gravity conditions. We also review the impact that gravity played in the anatomy of snakes and amphibians, during their evolution. Overall, it appears that gravity does not only curve the space–time continuum but the biological continuum, as well
Identification of Co-Deregulated Genes in Urinary Bladder Cancer Using High-Throughput Methodologies
Urinary bladder cancer (UBC) is the second most common urogenital solid tumor and the eleventh in the rank among all types of solid tumors. Although several oncogenes and tumor suppressors are known to be implicated in the disease, the list of candidate prognostic markers has recently expanded, as a result of the power of new high-throughput methodologies. The prognosis and therapy of UBC have progressed greatly during the last years. However, a majority of the different tumor subtypes still relapses, manifesting poor prognosis. Here, we identified gene expression patterns being common across different histological phenotypes of UBC. Such an approach could be useful in the discovery of prognostic and therapeutic targets able to be applied in the majority of the tumor’s subtypes
Information, Thermodynamics and Life: A Narrative Review
Information is probably one of the most difficult physical quantities to comprehend. This applies not only to the very definition of information, but also to the physical entity of information, meaning how can it be quantified and measured. In recent years, information theory and its function in systems has been an intense field of study, due to the large increase of available information technology, where the notion of bit dominated the information discipline. Information theory also expanded from the “simple” “bit” to the quantal “qubit”, which added more variables for consideration. One of the main applications of information theory could be considered the field of “autonomy”, which is the main characteristic of living organisms in nature since they all have self-sustainability, motion and self-protection. These traits, along with the ability to be aware of existence, make it difficult and complex to simulate in artificial constructs. There are many approaches to the concept of simulating autonomous behavior, yet there is no conclusive approach to a definite solution to this problem. Recent experimental results have shown that the interaction between machines and neural cells is possible and it consists of a significant tool for the study of complex systems. The present work tries to review the question on the interactions between information and life. It attempts to build a connection between information and thermodynamics in terms of energy consumption and work production, as well as present some possible applications of these physical quantities
Education Program for Carers in Facilities with Neuro Disabled Subjects EPoCFiNDS
The prevalence of chronic illness and the disabilities they cause are strongly associated with age. According tothe United Nations, in most countries around the world, 8-10% of the population has some form of disability.Carers are helping subjects who have severe or profound core activity limitations in the community and hospicefacilities. The skills acquired by carers in their caring role are relevant to the competencies required for occupationsand qualifications in community, aged care, health, youth, housing and disability support services. With the agingpopulation the number of subjects with neurological lesions living in hospices and long-term care facilities isincreased. It makes a strong case to educate carers to help these subjects. There is a lack of evidence on howto design and implement mechanisms such as foundation skills courses and programs to best meet the needsof carers. The goal of Education Program for Carers in Facilities with Neuro Disabled Subjects (EPoCFiNDS), isto create training programs for carers in neurodisabled subjects living in various facilities. In Europe we need todevelop educational programs, aimed at volunteers, relatives or any other group of people so that they betterorganize benefits care for neurodisabled subjects
Protocols, performance assessment and consolidation on interfaces for standardization – D3.3
The following document presents a detailed description of the protocol for the “
Control Channels for the Cooperation of the Cognitive Management System
” (C4MS) which provides the necessary means
to enable proper management of Opportunistic Networks.
Additionally, the document defines the
methodology that was applied for the purpose of signalling evaluation.
The protocol overview presented in section
2 of the main document, provides the
C4MS principles.
The section includes, among others, the description of the protocol identifiers,
procedures, protocol state machines and message format as well as the security asp
ects.
Section 3 provides a high-level description of the data structures defined within the scope of OneFIT project. The data structures are classified into five categories, i.e.: Profiles, Context, Decisions,Knowledge and Policies. The high level description is complemented by some detailed data
structures in the Appendix to D3.3 Section
3[10].
Section 4 provides details on the evaluation methodology applied for the purpose of C4MS
performance assessment. The section presents
the evaluation plan along with a description of metrics that are to be exploited in the scope of WP3.
Section 5 and Section 6 are composed of the signalling evaluation results. Section 5
focuses on the estimation of the signalling load imposed by ON management in different ON phases. Additionally some results for the initialization phase (not explicitly mentioned in the previous phases of the
project)and security related aspects are also depicted. Section 6 on the other hand is
focused on the evaluation of the
signalling traffic generated by
different ON related algorithms.
Conclusions to the document are drawn in section 7. Detailed description of the C4MS procedures, implementation options based on IEEE 802.21, DIAMTER and 3GPP are depicted in the appendix to the D3.3[10]
. Additionally, the appendix incorporates the detailed definition of the information data structures and final set of Message Sequence Charts (MSCs) provided for
the OneFIT project.Peer ReviewedPreprin
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