High-frequency Oscillations in Epilepsy: What Have We Learned and What Needs to be Addressed

Neurology ◽  
2021 ◽  
pp. 10.1212/WNL.0000000000011465 ◽  
Author(s):  
Zhuying Chen ◽  
Matias I. Maturana ◽  
Anthony N. Burkitt ◽  
Mark J. Cook ◽  
David B. Grayden
Keyword(s):  
High Frequency ◽  
Future Research ◽  
Great Promise ◽  
Clinical Biomarkers ◽  
High Frequency Oscillations ◽  
Visual Identification ◽  
Current State ◽  
Open Questions ◽  
Term Data

For the past two decades, high-frequency oscillations (HFOs) have been enthusiastically studied by the epilepsy community. Emerging evidence shows that HFOs harbour great promise to delineate epileptogenic brain areas and possibly predict the likelihood of seizures. Investigations into HFOs in clinical epilepsy have advanced from small retrospective studies relying on visual identification and correlation analysis to larger prospective assessments using automatic detection and prediction strategies. While most studies have yielded promising results, some have revealed significant obstacles to clinical application of HFOs, thus raising debate about the reliability and practicality of HFOs as clinical biomarkers. In this review, we give an overview of the current state of HFO research and pinpoint the conceptual and methodological issues that have hampered HFO translation. We highlight recent insights gained from long-term data, high-density recordings and multicentre collaborations, and discuss the open questions that need to be addressed in future research.

scholarly journals Hepatic stellate cells: current state and open questions

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Claus Kordes ◽  
Hans H. Bock ◽  
Doreen Reichert ◽  
Petra May ◽  
Dieter Häussinger
Keyword(s):  
Hepatic Stellate Cells ◽  
Stellate Cells ◽  
Essential Elements ◽  
Future Research ◽  
Heinrich Heine ◽  
Current State ◽  
Open Questions ◽  
Sinusoidal Endothelium ◽  
Cell Niche ◽  
Space Of Disse

Abstract This review article summarizes 20 years of our research on hepatic stellate cells within the framework of two collaborative research centers CRC575 and CRC974 at the Heinrich Heine University. Over this period, stellate cells were identified for the first time as mesenchymal stem cells of the liver, and important functions of these cells in the context of liver regeneration were discovered. Furthermore, it was determined that the space of Disse – bounded by the sinusoidal endothelium and hepatocytes – functions as a stem cell niche for stellate cells. Essential elements of this niche that control the maintenance of hepatic stellate cells have been identified alongside their impairment with age. This article aims to highlight previous studies on stellate cells and critically examine and identify open questions and future research directions.

Second language structural priming: A critical review and directions for future research

2017 ◽  
Vol 34 (4) ◽  
pp. 539-552 ◽  
Author(s):  
Carrie N. Jackson
Keyword(s):  
Second Language ◽  
Future Research ◽  
Structural Priming ◽  
Cognitive Mechanisms ◽  
L2 Acquisition ◽  
Current State ◽  
Current Review ◽  
Open Questions ◽  
Key Issues ◽  
State Of Research

The last 15 years has seen a tremendous growth in research on structural priming among second language (L2) speakers. Structural priming is the phenomenon whereby speakers are more likely to repeat a structure they have recently heard or produced. Research on L2 structural priming speaks to key issues regarding the underlying linguistic and cognitive mechanisms that support L2 acquisition and use, and the extent to which lexical and grammatical information are shared across an L2 speaker’s languages. As the number of researchers investigating L2 priming and its implications for L2 learning continues to grow, it is important to assess the current state of research in this area and establish directions for continued inquiry. The goal of the current review is to provide an overview of recent research on within-language L2 structural priming, with an eye towards the open questions that remain.

Beyond Micro-Tasks

2018 ◽  
Vol 29 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Roman Lukyanenko ◽  
Jeffrey Parsons
Keyword(s):  
Data Acquisition ◽  
Data Management ◽  
Future Research ◽  
Information Production ◽  
Management Research ◽  
Research Attention ◽  
Important Type ◽  
Sensory Ability ◽  
Term Data

The emergence of crowdsourcing as an important mode of information production has attracted increasing research attention. In this article, the authors review crowdsourcing research in the data management field. Most research in this domain can be termed tasked-based, focusing on micro-tasks that exploit scale and redundancy in crowds. The authors' review points to another important type of crowdsourcing – which they term observational – that can expand the scope of extant crowdsourcing data management research. Observational crowdsourcing consists of projects that harness human sensory ability to support long-term data acquisition. The authors consider the challenges in this domain, review approaches to data management for crowdsourcing, and suggest directions for future research that bridges the gaps between the two research streams.

scholarly journals Stereotyped high-frequency oscillations discriminate seizure onset zones and critical functional cortex in focal epilepsy

Brain ◽  
2018 ◽  
Vol 141 (3) ◽  
pp. 713-730 ◽  
Author(s):  
Su Liu ◽  
Candan Gurses ◽  
Zhiyi Sha ◽  
Michael M Quach ◽  
Altay Sencer ◽  
...  
Keyword(s):  
High Frequency ◽  
Focal Epilepsy ◽  
Machine Learning Techniques ◽  
Seizure Onset ◽  
Functional Regions ◽  
Clinical Biomarkers ◽  
High Frequency Oscillations ◽  
Potential Association ◽  
Waveform Similarity ◽  
Seizure Onset Zones

Abstract High-frequency oscillations in local field potentials recorded with intracranial EEG are putative biomarkers of seizure onset zones in epileptic brain. However, localized 80–500 Hz oscillations can also be recorded from normal and non-epileptic cerebral structures. When defined only by rate or frequency, physiological high-frequency oscillations are indistinguishable from pathological ones, which limit their application in epilepsy presurgical planning. We hypothesized that pathological high-frequency oscillations occur in a repetitive fashion with a similar waveform morphology that specifically indicates seizure onset zones. We investigated the waveform patterns of automatically detected high-frequency oscillations in 13 epilepsy patients and five control subjects, with an average of 73 subdural and intracerebral electrodes recorded per patient. The repetitive oscillatory waveforms were identified by using a pipeline of unsupervised machine learning techniques and were then correlated with independently clinician-defined seizure onset zones. Consistently in all patients, the stereotypical high-frequency oscillations with the highest degree of waveform similarity were localized within the seizure onset zones only, whereas the channels generating high-frequency oscillations embedded in random waveforms were found in the functional regions independent from the epileptogenic locations. The repetitive waveform pattern was more evident in fast ripples compared to ripples, suggesting a potential association between waveform repetition and the underlying pathological network. Our findings provided a new tool for the interpretation of pathological high-frequency oscillations that can be efficiently applied to distinguish seizure onset zones from functionally important sites, which is a critical step towards the translation of these signature events into valid clinical biomarkers. 5721572971001 awx374media1 5721572971001

scholarly journals Closing the Capacity-Ability Gap: Using Technology to Support Aging With Disability

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Tracy L Mitzner ◽  
Jon A Sanford ◽  
Wendy A Rogers
Keyword(s):  
Great Promise ◽  
User Requirements ◽  
Intervention Model ◽  
Current State ◽  
Age Related ◽  
Wide Range ◽  
Technology Intervention ◽  
Bridge Models ◽  
Age Related Changes

Abstract There is a critical need to develop supports for older adults who have a wide range of abilities, including those aging with long-term impairments. Without appropriate support, many individuals will be functioning below optimal levels and will face participation barriers. Technology holds great promise to provide individualized support for a wide range of abilities and for a variety of domains. To ensure technology interventions are designed well and meet research-documented user requirements, we need more specific, actionable models to provide guidance for those developing and designing interventions. In this paper, we present the TechSAge Aging and Disability Model to bridge models from the aging and disability literatures and to disambiguate the population of individuals aging into disability from those aging with disability (i.e., pre-existing impairments). We also present the TechSAge Technology Intervention Model to support aging with pre-existing impairments, which provides direction and touch points for technology interventions. These models reflect the complex and dynamic interaction between age-related changes and an individual’s prior capabilities and limitations. We describe the need for these models with respect to filling a gap in the disability and aging literature by highlighting the importance of differentiating between age-related changes and long-term impairments when designing interventions. We also show the need for quantitative and qualitative data to refine the models given complexities of the current state of the literature and survey data. The TechSAge Technology Intervention Model can be used to drive and inform technology redesign and development.

Meinungsbildung in der Netzöffentlichkeit

2019 ◽  
Keyword(s):  
Social Media ◽  
Public Communication ◽  
Future Research ◽  
Digital Revolution ◽  
The Public ◽  
Empirical Basis ◽  
Current State ◽  
Open Questions ◽  
State Of Research

This volume offers insights into current research on the reception and effects of the digital revolution in public communication in the field of communication science. The contributions it contains deal with questions about the use of news on Facebook, the articulation of opinions on the public Net and the influencing of opinions on social media (e.g. by influencers). They document the current state of research and knowledge in this field, answer current open questions on an empirical basis and provide suggestions for future research. With contributions by Patrick Weber, Frank Mangold, Miriam Steiner, Melanie Magin, Birgit Stark, Pascal Jürgens, Anna Sophie Kümpel, Larissa Leonhard, Veronika Karnowski, Claudia Wilhelm, Ines Engelmann, Stefan Geiß, German Neubaum, Manuel Cargnino, Davina Berthelé, Priska Breves, Helene Schüler, Benedikt Spangardt, Kerstin Thummes

P339 Long-term electrocorticographic monitoring and pathological high-frequency oscillations in tumor-related epilepsy

2017 ◽  
Vol 128 (9) ◽  
pp. e288
Author(s):  
Nastasia Arkhipova ◽  
Mikhail Alexandrov ◽  
Alexander Chukhlovin ◽  
Marina Pavlovskaya ◽  
Irina Kostenko
Keyword(s):  
High Frequency ◽  
High Frequency Oscillations

scholarly journals Using a Mobile Social Networking App to Promote Physical Activity: A Qualitative Study of Users’ Perspectives (Preprint)

2018 ◽  
Author(s):  
Huong Ly Tong ◽  
Enrico Coiera ◽  
Liliana Laranjo
Keyword(s):  
Physical Activity ◽  
Social Networking ◽  
Physical Activity Intervention ◽  
Adult Population ◽  
Qualitative Interviews ◽  
Mobile App ◽  
Future Research ◽  
Great Promise ◽  
Mobile Social Networking

BACKGROUND Despite many health benefits of physical activity, nearly a third of the world’s adult population is insufficiently active. Technological interventions, such as mobile apps, wearable trackers, and Web-based social networks, offer great promise in promoting physical activity, but little is known about users’ acceptability and long-term engagement with these interventions. OBJECTIVE The aim of this study was to understand users’ perspectives regarding a mobile social networking intervention to promote physical activity. METHODS Participants, mostly university students and staff, were recruited using purposive sampling techniques. Participants were enrolled in a 6-month feasibility study where they were provided with a wearable physical activity tracker (Fitbit Flex 2) and a wireless scale (Fitbit Aria) integrated with a social networking mobile app (named “fit.healthy.me”). We conducted semistructured, in-depth qualitative interviews and focus groups pre- and postintervention, which were recorded and transcribed verbatim. The data were analyzed in Nvivo 11 using thematic analysis techniques. RESULTS In this study, 55 participants were enrolled; 51% (28/55) were females, and the mean age was 23.6 (SD 4.6) years. The following 3 types of factors emerged from the data as influencing engagement with the intervention and physical activity: individual (self-monitoring of behavior, goal setting, and feedback on behavior), social (social comparison, similarity and familiarity between users, and participation from other users in the network), and technological. In addition, automation and personalization were observed as enhancing the delivery of both individual and social aspects. Technological limitations were mentioned as potential barriers to long-term usage. CONCLUSIONS Self-regulatory techniques and social factors are important to consider when designing a physical activity intervention, but a one-size-fits-all approach is unlikely to satisfy different users’ preferences. Future research should adopt innovative research designs to test interventions that can adapt and respond to users’ needs and preferences throughout time.

scholarly journals Anaphora With Non-nominal Antecedents in Computational Linguistics: a Survey

2018 ◽  
Vol 44 (3) ◽  
pp. 547-612 ◽  
Author(s):  
Varada Kolhatkar ◽  
Adam Roussel ◽  
Stefanie Dipper ◽  
Heike Zinsmeister
Keyword(s):  
Computational Linguistics ◽  
Question Answering ◽  
Future Research ◽  
Good Picture ◽  
Text Understanding ◽  
Theoretical Approaches ◽  
Current State ◽  
Open Questions ◽  
Work Done ◽  
Computational Systems

This article provides an extensive overview of the literature related to the phenomenon of non-nominal-antecedent anaphora (also known as abstract anaphora or discourse deixis), a type of anaphora in which an anaphor like “that” refers to an antecedent (marked in boldface) that is syntactically non-nominal, such as the first sentence in “It’s way too hot here. That’s why I’m moving to Alaska.” Annotating and automatically resolving these cases of anaphora is interesting in its own right because of the complexities involved in identifying non-nominal antecedents, which typically represent abstract objects such as events, facts, and propositions. There is also practical value in the resolution of non-nominal-antecedent anaphora, as this would help computational systems in machine translation, summarization, and question answering, as well as, conceivably, any other task dependent on some measure of text understanding. Most of the existing approaches to anaphora annotation and resolution focus on nominal-antecedent anaphora, classifying many of the cases where the antecedents are syntactically non-nominal as non-anaphoric. There has been some work done on this topic, but it remains scattered and difficult to collect and assess. With this article, we hope to bring together and synthesize work done in disparate contexts up to now in order to identify fundamental problems and draw conclusions from an overarching perspective. Having a good picture of the current state of the art in this field can help researchers direct their efforts to where they are most necessary. Because of the great variety of theoretical approaches that have been brought to bear on the problem, there is an equally diverse array of terminologies that are used to describe it, so we will provide an overview and discussion of these terminologies. We also describe the linguistic properties of non-nominal-antecedent anaphora, examine previous annotation efforts that have addressed this topic, and present the computational approaches that aim at resolving non-nominal-antecedent anaphora automatically. We close with a review of the remaining open questions in this area and some of our recommendations for future research.

scholarly journals The effects of phenological mismatches on demography

2010 ◽  
Vol 365 (1555) ◽  
pp. 3177-3186 ◽  
Author(s):  
Abraham J. Miller-Rushing ◽  
Toke Thomas Høye ◽  
David W. Inouye ◽  
Eric Post
Keyword(s):  
Future Research ◽  
Sensitive Species ◽  
Know How ◽  
Phenological Changes ◽  
The World ◽  
Term Data ◽  
Demographic Effects ◽  
Long Term Studies ◽  
Key Questions

Climate change is altering the phenology of species across the world, but what are the consequences of these phenological changes for the demography and population dynamics of species? Time-sensitive relationships, such as migration, breeding and predation, may be disrupted or altered, which may in turn alter the rates of reproduction and survival, leading some populations to decline and others to increase in abundance. However, finding evidence for disrupted relationships, or lack thereof, and their demographic effects, is difficult because the necessary detailed observational data are rare. Moreover, we do not know how sensitive species will generally be to phenological mismatches when they occur. Existing long-term studies provide preliminary data for analysing the phenology and demography of species in several locations. In many instances, though, observational protocols may need to be optimized to characterize timing-based multi-trophic interactions. As a basis for future research, we outline some of the key questions and approaches to improving our understanding of the relationships among phenology, demography and climate in a multi-trophic context. There are many challenges associated with this line of research, not the least of which is the need for detailed, long-term data on many organisms in a single system. However, we identify key questions that can be addressed with data that already exist and propose approaches that could guide future research.

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