Active networking is an exciting new paradigm in digital networking that has the potential to revolutionize the manner in which communication takes place. It is an emerging technology, one in which new ideas are constantly being formulated and new topics of research are springing up even as this book is being written. This technology is very likely to appeal to a broad spectrum of users from academia and industry. Therefore, this book was written in a way that enables all (...) these groups to understand the impact of active networking in their sphere of interest. Information services managers, network administrators, and e-commerce developers would like to know the potential benefits of the new technology to their businesses, networks, and applications. The book introduces the basic active networking paradigm and its potential impacts on the future of information handling in general and on communications in particular. This is useful for forward-looking businesses that wish to actively participate in the development of active networks and ensure a head start in the integration of the technology in their future products, be they applications or networks. Areas in which active networking is likely to make significant impact are identified, and the reader is pointed to any related ongoing research efforts in the area. The book also provides a deeper insight into the active networking model for students and researchers, who seek challenging topics that define or extend frontiers of the technology. It describes basic components of the model, explains some of the terms used by the active networking community, and provides the reader with taxonomy of the research being conducted at the time this book was written. Current efforts are classified based on typical research areas such as mobility, security, and management. The intent is to introduce the serious reader to the background regarding some of the models adopted by the community, to outline outstanding issues concerning active networking, and to provide a snapshot of the fast-changing landscape in active networking research. Management is a very important issue in active networks because of its open nature. The latter half of the book explains the architectural concepts of a model for managing active networks and the motivation for a reference model that addresses limitations of the current network management framework by leveraging the powerful features of active networking to develop an integrated framework. It also describes a novel application enabled by active network technology called the Active Virtual Network Management Prediction (AVNMP) algorithm. AVNMP is a proactive management system; in other words, it provides the ability to solve a potential problem before it impacts the system by modeling network devices within the network itself and running that model ahead of real time. (shrink)

This chapter considers how activism networks—including counter-colonial social mobilisation that might take various forms—can help to generate vital spaces of learning inside, and outside, the classroom. Reflections explore the roles of diaspora and other diverse groups in society in anti-deportation rallies, including in raising critical consciousness in public media, supporting grassroots funding and building intercultural avenues for exchange in displaced communities. We consider examples of teaching and knowledge-sharing that offered attention to experiences of coming from Iraq to Scotland and (...) building networks of activism and advocacy as part of the Refugees for Justice initiative. We also reflect on differentiated kinds of non-governmental organisations that are differently positioned within contesting state politics and grassroots organising; and we explore the possibilities of diaspora networks that re-orient critical consciousness regarding both international and local political struggles. Additional curriculum examples include exploration of struggles in communities displaced by British colonialism and settler-colonialism, relating to Canada, Zimbabwe and Palestine/Israel, and seeking to reclaim colonially dispossessed land, in some cases crossing borders as a result of that dispossession. Further examples harken to dilemmas faced in deciding between a United Nations diplomat or a grassroots social justice advocate as the “lead” for particular conversations in classrooms, and the dangers of pre-emptively assuming too much about “realism” and “what is practical” as the basis for mobilising for social change. We also briefly gesture to teaching moments related to the student encampments set up in the spring of 2024 in an attempt to change university policies relating to military violence in the context of Israel/Palestine. Complex outcomes of various movement-led and community-led efforts are explored, and brief wider reflections on the possibilities of counter-hegemonic thought in teaching about displacement conclude the chapter. (shrink)

Spontaneous activity levels prior to stimulus presentation can determine how that stimulus will be perceived. It has also been proposed that such spontaneous activity, particularly in the default-mode network (DMN), is involved in self-related processing. We therefore hypothesised that pre-stimulus activity levels in the DMN predict whether a stimulus is judged as self-related or not. Method: Participants were presented in the MRI scanner with a white noise stimulus that they were instructed contained their name or another. They then had to (...) respond with which name they thought they heard. Regions where there was an activity level difference between self and other response trials two seconds prior to the stimulus being presented were identified. Results: Pre-stimulus activity levels were higher in the right temporoparietal junction (RTPJ), the right temporal pole (RTP), and the left superior temporal gyrus in trials where the participant responded that they heard their own name than trials where they responded that they heard another. Conclusion: Pre-stimulus spontaneous activity levels in particular brain regions, largely overlapping with the DMN, predict the subsequent judgement of stimuli as self-related. This extends our current knowledge of self-related processing and its apparent relationship with intrinsic brain activity in what can be termed a rest-self overlap. (shrink)

Localist models of spreading activation (SA) and models assuming distributed representations offer very different takes on semantic priming, a widely investigated paradigm in word recognition and semantic memory research. In this study, we implemented SA in an attractor neural network model with distributed representations and created a unified framework for the two approaches. Our models assume a synaptic depression mechanism leading to autonomous transitions between encoded memory patterns (latching dynamics), which account for the major characteristics of automatic semantic priming in (...) humans. Using computer simulations, we demonstrated how findings that challenged attractor‐based networks in the past, such as mediated and asymmetric priming, are a natural consequence of our present model’s dynamics. Puzzling results regarding backward priming were also given a straightforward explanation. In addition, the current model addresses some of the differences between semantic and associative relatedness and explains how these differences interact with stimulus onset asynchrony in priming experiments. (shrink)

A ubiquitous feature of active sleep in mammals and birds is its relative abundance in early development. In rat pups across the first two postnatal weeks, active sleep promotes the expression of synchronized oscillatory activity within and between cortical and subcortical sensorimotor structures. Sensory feedback from self-generated myoclonic twitches – which are produced exclusively during active sleep – also triggers neural oscillations in those structures. We have proposed that one of the functions of active sleep in (...) early infancy is to provide a context for synchronizing developing structures. Specifically, neural oscillations contribute to a variety of neurodevelopmental processes, including synapse formation, neuronal differentiation and migration, apoptosis, and the refinement of topographic maps. In addition, synchronized oscillations promote functional connectivity between distant brain areas. Consequently, any condition or manipulation that restricts active sleep can, in turn, deprive the infant animal of substantial sensory experience, resulting in atypical developmental trajectories. The synchronization of rhythmic neural activity across brain structures provides evidence of communication. In developing sensorimotor networks, such oscillations are triggered most clearly and prominently during REM sleep. We propose that REM sleep provides a context for the emergence and expression of functional connectivity in the developing sensorimotor system. (shrink)

The complex activity of the human brain makes it difficult to get a big picture of how the brain works and functions as the mind. We examine pertinent studies, as well as evolutionary and embryologic evidence to support our theoretical model consisting of separate but interactive layers of human neural activity. The most basic layer involves default mode network (DMN)activity and cardiorespiratory oscillations. We propose that these oscillations support other neural activity and cognitive processes. The second layer involves limbic system (...) activity accompanied by corresponding changes in cardiorespiratory oscillations. The third layer consists of corticothalamic processing and involves higher cortical functions including awareness, cognition,and consciousness. These layers interact to form the complex neural activity of the human brain. Examining the origins and relationships of various neural and physiologic oscillations may provide better understanding of human neurophysiology and consciousness. (shrink)

The growing availability and consumption of Fairtrade products is recognised as one of the most widespread ethically inspired market developments, and as an example of activist-driven change within the wider marketing system. The Fairtrade Towns movement, now operating in over 1700 towns and cities globally, represents a comparatively recent extension of Fairtrade marketing driven by local activists seeking to promote positive change in production and consumption systems. This paper briefly explores the conventional framing of the role that ethically related activism (...) plays in the operation of markets and in influencing market participants. It then presents key insights gathered from a grounded theory exploration of Fairtrade Towns as activist-driven marketing systems, revealing the atypical nature of the activism involved. The findings demonstrate how local activists leverage their social networks to exert pressure and generate support to promote ethical consumption. The study suggests that Fairtrade Towns offer a new role for activists as Fairtrade itself becomes more mainstream, and considers the role they are fulfilling as ‘informal’ local marketers. The marketing dynamics revealed represent a complex and distinctive form of relational activism that seeks to build Fairtrade markets and highlight their positive benefits, with potential lessons for other local ethical market-building efforts in future. (shrink)

In this paper, through research and analysis of the communication network of the physical activity monitoring system, we combine wearable technology and identification technology and design a physical health monitoring bracelet that integrates multifaceted physical data collection and effective identity matching function. We match the identity through the chip and collect the physical fitness data generated in the process of exercise and centralized test by the sensor in real-time. Finally, the data transmission is realized through the WIFI communication function to (...) achieve the purpose of monitoring physical exercise and improving physical quality. To ensure the continuity and stability of information transmission, the joint transmission method of direct transmission and indirect transmission is essential. Besides, considering the energy causality limitation of sensor nodes and relay nodes, a collaborative transmission model of wireless body area network based on wireless cognitive network is constructed. And, a power allocation algorithm based on maximum ratio merging and wireless cognitive network is proposed, which puts forward a new idea for the future research of wireless body area network resource allocation. (shrink)

This paper examines the motivation theory of Rowley and Moldoveanu (2003) on shareholder activism in the context of shareholder resolution networks. Shareholder resolution filings occur both within subnetworks as well as across subnetworks, indicating these motivations are mixed. I extend the motivational issue by also examining the response of the corporation to such activism. That resolutions might migrate from identity to interest motivated groups is examined as an element of future research.

Coordination is a key problem for addressing goal–action gaps in many human endeavors. We define interpersonal coordination as a type of communicative action characterized by low interpersonal belief and goal conflict. Such situations are particularly well described as having collectively “intelligent”, “common good” solutions, viz., ones that almost everyone would agree constitute social improvements. Coordination is useful across the spectrum of interpersonal communication—from isolated individuals to organizational teams. Much attention has been paid to coordination in teams and organizations. In this (...) paper we focus on the looser interpersonal structures we call active support networks, and on technology that meets their needs. We describe two needfinding investigations focused on social support, which examined four application areas for improving coordination in ASNs: academic coaching, vocational training, early learning intervention, and volunteer coordination; and existing technology relevant to ASNs. We find a thus-far unmet need for personal task management software that allows smooth integration with an individual’s active support network. Based on identified needs, we then describe an open architecture for coordination that has been developed into working software. The design includes a set of capabilities we call “social prompting”, as well as templates for accomplishing multi-task goals, and an engine that controls coordination in the network. The resulting tool is currently available and in continuing development. We explain its use in ASNs with an example. Follow-up studies are underway in which the technology is being applied in existing support networks. (shrink)

This article examines the survival and revival strategies of Hizbut Tahrir, affiliated activism in Indonesia following the state dissolution of Hizbut Tahrir Indonesia (HTI) in 2017. Challenging the assumption that the banning of Islamist organizations necessarily leads to organizational and ideological decline, the article argues that HTI’s dissolution prompted a strategic reconfiguration of Tahriri activism. Drawing on resource mobilization theory, the study analyzes how former HTI activists reorganized informal networks, symbolic resources, and digital media to sustain the movement under (...) increasingly restrictive political conditions. Based on digital ethnography and content analysis of Instagram and YouTube platforms between 2017 and 2020, the article focuses on three key cases: Felix Siauw, Yuk Ngaji, and Khilafah Channel. The findings show a shift from formal organizational structures to more fluid, decentralized, and digitally oriented forms of activism. At the discursive level, key ideological concepts such as democracy, Pancasila, and the caliphate are pragmatically rearticulated in non-confrontational ways, less as state-oriented political projects than as moral and cultural frameworks for Muslim everyday life. This adaptation reflects a strategic response to state repression rather than a substantive ideological transformation. (shrink)

Urban networks have been widely examined using infrastructure connection and firm connection data. In particular, urban networks constructed based on firm connection data have been used to depict the circulation of capital, information, personnel, and products between cities. Existing studies on firm connection networks rely on either inter- or intrafirm relationships. However, there exist various important extra-firm relationships, such as those between firms and governments, research institutions, and nonprofit organizations. This study innovatively incorporates the extra-firm relationships between (...) governments and firms into urban network construction to provide new insights into the field of urban network research. Using Northeast China as a case study, we construct government procurement activity connection networks for both central projects and local projects at the regional and national scales. Social network analysis and regression analysis are used to analyze the network characteristics and factors associated with the network structure. The results show that three provincial capitals hold dominant positions across all the networks. While these capitals serve as GPA suppliers in the region, they are mainly GPA consumers nationally. The factors of spatial proximity, economic development, population, and provincial boundaries were found to be significantly associated with GPA connections. Our study provides important insights into the role of cities in firm-government supply-demand networks. This research can be used to help formulate effective strategies to improve a city’s competitiveness and cities’ cooperation in the GPA supply-demand network. (shrink)

The main purpose of this article is to identify the inner human activity Peirce calls musement with the mental processes that arise through the workings of the brain’s default mode network. This network is a specific, recently anatomically defined brain system, which is most active when individuals are not focused on the external environment. In doing so, musement, which was defined by Peirce over a hundred years ago, will finally be situated within what today we understand as its neurobiological (...) origin. (shrink)

With the development of distributed networks, the remote controllability of the distributed energy objects and the vulnerability of user-side information security protection measures make distributed energy objects extremely vulnerable to malicious control by attackers. Hence, the large-scale loads may produce abnormal operation performance, such as load casting/dropping synchronously or frequent and synchronous casting and dropping, and hence, it can threaten the security and stable operation of the distribution networks. First, we analyze the security threats faced by industrial controllable (...) load, civil controllable load, and the gains and losses of attacks on the distribution networks. Considering the factors of cyber attacks, we propose a control model and cyber attack model in active distribution networks. And, three types of attacks that the target suffered are defined on the basis of “on” and “off” modes for control. Then, the controllable load was maliciously controlled as the research object, and a suitable scenario is selected. The impact of malicious control of the controllable load on the power supply reliability and power quality of the distribution networks are simulated and analyzed, and risk consequences for different types of attacks are provided. (shrink)

This paper presents the architecture and initial feasibility results of a proto-type communication network that utilizes genetic programming to evolve services and protocols as part of network operation. The network evolves responses to environmental conditions in a manner that could not be preprogrammed within legacy network nodes a priori. A priori in this case means before network operation has begun. Genetic material is exchanged, loaded, and run dynamically within an active network. The transfer and execution of code in support (...) of the evolution of network protocols and services would not be possible without the active network environment. Rapid generation of network service code occurs via a genetic programming paradigm. Complexity and Algorithmic Information Theory play a key role in understanding and guiding code evolution within the network. (shrink)

Recent evidence points to widespread underconnectivity in autistic brains owing to deviant white matter, the fibers that make long connections between areas of the cortex. Subjects with autism show measurably fewer long-range connections between the parietal and prefrontal cortices. These findings may help shed light on the current debate in the consciousness literature about whether conscious states require both prefrontal and parietal/temporal components. If it can be shown that people with autism have conscious states despite such underconnectivity, this would constitute (...) an argument for the claim that conscious states can exist in posterior cortex without associated prefrontal activity. This in turn lends support to a class of theories according to which microconsciousness is possible—consciousness in small areas of cortex without active connections to the prefrontal cortex, as opposed to the higher-order thought (HOT) theory of consciousness, according to which conscious states can only occur when posterior cortical areas (in the parietal or temporal lobes) have active connections to the prefrontal cortex. In this chapter, after listing several candidate examples of consciousness without accompanying prefrontal connections, I will argue that autism provides yet another such example. I will also examine a recent version of the higher-order theory that acknowledges these cases of consciousness without prefrontal activity and, instead depicts consciousness as requiring higher-order thoughts located in posterior cortex. In the final section, I will examine the consequences of these views for our understanding of the metaphysical nature of consciousness itself—the classic mind-body problem. (shrink)

This essay bridges together social network and institutional perspectives to examine how women on boards, by breaking up directors’ homophilous networks, contribute to board effectiveness. It proposes that through real and symbolic representations, women enhance perceptions of the board’s instrumental, relational, and moral legitimacy, leading to increased perceptions of the board’s trustworthiness which in turn fosters shareholders’ trust in the firm. Envisioning the gender diversification of boards as an event of institutional change, this article considers the critical role of (...) shareholder activists and legislative support from the SEC in the deinstitutionalization of old boys’ networks and the reinstitutionalization of gender diverse boards. This work is substantiated with evidence obtained through 34 semi-structured interviews, archival and documentary evidence. (shrink)

This article explores the activities of the Society of Apothecaries and its members following the foundation of a laboratory for manufacturing chemical medicines in 1672. In response to political pressures, the guild created an institutional framework for production which in time served its members both functionally and financially and established a physical site within which the endorsement of practical knowledge could take place. Demand from state and institutional customers for drugs produced under corporate oversight affirmed and supported the society's trading (...) role, with chemical and pharmaceutical knowledge utilized to fulfil collective and individual goals. The society benefited from the mercantile interests, political connections and practical expertise of its members, with contributions to its trading activities part of a much wider participation in London's medical, scientific and commercial milieu. Yet, as apothecaries became increasingly engaged in the practice of medicine rather than the preparation and sale of drugs, the society struggled to reconcile the changing priorities of those it represented, and tensions emerged between its corporate and commercial activities. (shrink)

Spontaneous brain activity has received increasing attention as demonstrated by the exponential rise in the number of published papers on this topic over the last thirty years. Such “intrinsic” brain activity, generated in the absence of an explicit task, is frequently associated with resting-state or default-mode networks. The focus on characterizing spontaneous brain activity promises to shed new light on questions concerning the structural and functional architecture of the brain and how they are related to “mind”. However, many critical (...) questions have yet to be addressed. In this review, we focus on a scarcely explored area, specifically the energetic requirements and constraints of spontaneous activity, taking into account both thermodynamical and informational perspectives. We argue that the “classical” definitions of spontaneous activity do not take into account an important feature, that is, the critical thermodynamic energetic differences between spontaneous and evoked brain activity. Spontaneous brain activity is associated with slower oscillations compared with evoked, task-related activity, hence it exhibits lower levels of enthalpy and “free-energy” (i.e. the energy that can be converted to do work), thus supporting noteworthy thermodynamic energetic differences between spontaneous and evoked brain activity. Increased spike frequency during evoked activity has a significant metabolic cost, consequently, brain functions traditionally associated with spontaneous activity, such as mind wandering, require less energy that other nervous activities. We also review recent empirical observations in neuroscience, in order to capture how spontaneous brain dynamics and mental function can be embedded in a non-linear dynamical framework, which considers nervous activity in terms of phase spaces, particle trajectories, random walks, attractors and/or paths at the edge of the chaos. This takes us from the thermodynamic free-energy, to the realm of “variational free-energy”, a theoretical construct pertaining to probability and information theory which allows explanation of unexplored features of spontaneous brain activity. (shrink)

ObjectiveStatic regional homogeneity based on the resting-state functional magnetic resonance imaging has been used to study intrinsic brain activity in Alzheimer’s disease. However, few studies have examined dynamic ReHo in AD. In this study, we used rs-fMRI and dReHo to investigate the alterations in dynamic IBA in patients with AD to uncover dynamic imaging markers of AD.MethodIn total, 111 patients with AD, 29 patients with mild cognitive impairment, and 73 healthy controls were recruited for this study ultimately. After the rs-fMRI (...) scan, we calculated the dReHo values using the sliding window method. ANOVA and post hoc two-sample t-tests were used to detect the differences among the three groups. We used the mini-mental state examination and Montreal Cognitive Assessment to evaluate the cognitive function of the subjects. The associations between the MMSE score, MoCA score, and dReHo were assessed by the Pearson correlation analysis.ResultsSignificant dReHo variability in the right middle frontal gyrus and right posterior cingulate gyrus was detected in the three groups through ANOVA. In post hoc analysis, the AD group exhibited significantly greater dReHo variability in the right MFG than the MCI group. Compared with the HC group, the AD group exhibited significantly increased dReHo variability in the right PCG. Furthermore, dReHo variability in the right PCG was significantly negatively correlated with the MMSE and MoCA scores of patients with AD.ConclusionDisrupted dynamic IBA in the DMN might be an important characteristic of AD and could be a potential biomarker for the diagnosis or prognosis of AD. (shrink)

Active networking is an exciting new paradigm in digital networking that has the potential to revolutionize the manner in which communication takes place. It is an emerging technology, one in which new ideas are constantly being formulated and new topics of research are springing up even as this book is being written. This technology is very likely to appeal to a broad spectrum of users from academia and industry. Therefore, this book was written in a way that enables all (...) these groups to understand the impact of active networking in their sphere of interest. Information services managers, network administrators, and e-commerce developers would like to know the potential benefits of the new technology to their businesses, networks, and applications. The book introduces the basic active networking paradigm and its potential impacts on the future of information handling in general and on communications in particular. This is useful for forward-looking businesses that wish to actively participate in the development of active networks and ensure a head start in the integration of the technology in their future products, be they applications or networks. Areas in which active networking is likely to make significant impact are identified, and the reader is pointed to any related ongoing research efforts in the area. The book also provides a deeper insight into the active networking model for students and researchers, who seek challenging topics that define or extend frontiers of the technology. It describes basic components of the model, explains some of the terms used by the active networking community, and provides the reader with taxonomy of the research being conducted at the time this book was written. Current efforts are classified based on typical research areas such as mobility, security, and management. The intent is to introduce the serious reader to the background regarding some of the models adopted by the community, to outline outstanding issues concerning active networking, and to provide a snapshot of the fast-changing landscape in active networking research. Management is a very important issue in active networks because of its open nature. The latter half of the book explains the architectural concepts of a model for managing active networks and the motivation for a reference model that addresses limitations of the current network management framework by leveraging the powerful features of active networking to develop an integrated framework. It also describes a novel application enabled by active network technology called the Active Virtual Network Management Prediction (AVNMP) algorithm. AVNMP is a proactive management system; in other words, it provides the ability to solve a potential problem before it impacts the system by modeling network devices within the network itself and running that model ahead of real time. (shrink)

This paper examines social network size in contemporary Western society based on the exchange of Christmas cards. Maximum network size averaged 153.5 individuals, with a mean network size of 124.9 for those individuals explicitly contacted; these values are remarkably close to the group size of 150 predicted for humans on the basis of the size of their neocortex. Age, household type, and the relationship to the individual influence network structure, although the proportion of kin remained relatively constant at around 21%. (...) Frequency of contact between network members was primarily determined by two classes of variable: passive factors (distance, work colleague, overseas) and active factors (emotional closeness, genetic relatedness). Controlling for the influence of passive factors on contact rates allowed the hierarchical structure of human social groups to be delimited. These findings suggest that there may be cognitive constraints on network size. (shrink)

The nature of “the self” has been one of the central problems in philosophy and more recently in neuroscience. This raises various questions: Can we attribute a self to animals? Do animals and humans share certain aspects of their core selves, yielding a trans-species concept of self? What are the neural processes that underlie a possible trans-species concept of self? What are the developmental aspects and do they result in various levels of self-representation? Drawing on recent literature from both human (...) and animal research, we suggest a trans-species concept of self that is based upon what has been called a “core-self” which can be described by self-related processing as a specific mode of interaction between organism and environment. When we refer to specific neural networks, we will here refer to the underlying system as the “core-SELF.” The core-SELF provides primordial neural coordinates that represent organisms as living creatures—at the lowest level this elaborates interoceptive states along with raw emotional feelings while higher medial cortical levels facilitate affective-cognitive integration . Developmentally, SRP allows stimuli from the environment to be related and linked to organismic needs, signaled and processed within core-self structures within subcorical-cortical midline structures that provide the foundation for epigenetic emergence of ecologically framed, higher idiographic forms of selfhood across different individuals within a species. These functions ultimately operate as a coordinated network. We postulate that core SRP operates automatically, is deeply affective, and is developmentally and epigenetically connected to sensory-motor and higher cognitive abilities. This core-self is mediated by SCMS, embedded in visceral and instinctual representations of the body that are well integrated with basic attentional, emotional and motivational functions that are apparently shared between humans, non-human mammals, and perhaps in a proto-SELF form, other vertebrates. Such a trans-species concept of organismic coherence is thoroughly biological and affective at the lowest levels of a complex neural network, and culturally and ecologically molded at higher levels of neural processing. It allows organisms to selectively adapt to and integrate with physical and social environments. Such a psychobiologically universal, but environmentally diversified, concept may promote novel trans-species studies of the core-self across mammalian species. (shrink)

What critical characteristics do firms have that determine the scale and scope of corporate social responsibility activities they undertake? This paper examines two disparate predictors of corporate social performance. First, using the lens of the resource-based view, we examine the role of alliance network centrality on corporate social performance. We find that centrality enhances corporate social performance. Second, we investigate how board composition affects corporate social performance. Specifically, drawing on stakeholder theory, we find that the percentage of female directors predicts (...) greater corporate social performance. In addition, we look at the influence of outside directors on this relationship. Our findings show that the presence of more outside directors positively moderates the relationship between female directors and corporate social performance. (shrink)

BackgroundFreezing of gait is a disabling burden for Parkinson’s disease patients with poor response to conventional therapies. Combined deep brain stimulation of the subthalamic nucleus and substantia nigra moved into focus as a potential therapeutic option to treat the parkinsonian gait disorder and refractory FoG. The mechanisms of action of DBS within the cortical-subcortical-basal ganglia network on gait, particularly at the cortical level, remain unclear.MethodsTwelve patients with idiopathic PD and chronically-implanted DBS electrodes were assessed on their regular dopaminergic medication in (...) a standardized stepping in place paradigm. Patients executed the task with DBS switched off, conventional STN DBS and combined STN+SN DBS and were compared to healthy matched controls. Simultaneous high-density EEG and kinematic measurements were recorded during resting-state, effective stepping, and freezing episodes.ResultsClinically, STN+SN DBS was superior to conventional STN DBS in improving temporal stepping variability of the more affected leg. During resting-state and effective stepping, the cortical activity of PD patients in STIM OFF was characterized by excessive over-synchronization in the theta, alpha, and high-beta band compared to healthy controls. Both active DBS settings similarly decreased resting-state alpha power and reduced pathologically enhanced high-beta activity during resting-state and effective stepping compared to STIM OFF. Freezing episodes during STN DBS and STN+SN DBS showed spectrally and spatially distinct cortical activity patterns when compared to effective stepping. During STN DBS, FoG was associated with an increase in cortical alpha and low-beta activity over central cortical areas, while with STN+SN DBS, an increase in high-beta was prominent over more frontal areas.ConclusionsSTN+SN DBS improved temporal aspects of parkinsonian gait impairment compared to conventional STN DBS and differentially affected cortical oscillatory patterns during regular locomotion and freezing suggesting a potential modulatory effect on dysfunctional cortical-subcortical communication in PD. (shrink)

Network motifs are small patterns of connections, found over‐represented in gene regulatory networks. An example is the negative feedback loop (e.g. factor A represses itself). This opposes its own state so that when ‘on’ it tends towards ‘off’ – and vice versa. Here, we argue that such self‐opposition, if considered dimensionlessly, is analogous to the liar paradox: ‘This statement is false’. When ‘true’ it implies ‘false’ – and vice versa. Such logical constructs have provided philosophical consternation for over 2000 (...) years. Extending the analogy, other network topologies give strikingly varying outputs over different dimensions. For example, the motif ‘A activates B and A. B inhibits A’ can give switches or oscillators with time only, or can lead to Turing‐type patterns with both space and time (spots, stripes or waves). It is argued here that the dimensionless form reduces to a variant of ‘The following statement is true. The preceding statement is false’. Thus, merely having a static topological description of a gene network can lead to a liar paradox. Network diagrams are only snapshots of dynamic biological processes and apparent paradoxes can reveal important biological mechanisms that are far from paradoxical when considered explicitly in time and space. (shrink)

More than three billion users are currently on one of Meta’s online platforms with Facebook being still their most prominent social media service. It is well known that Facebook has designed a highly immersive social media service with the aim to prolong online time of its users, as this results in more digital footprints to be studied and monetized. In this context, it is debated if social media platforms can elicit addictive behaviors. In the present work, we demonstrate in N (...) = 1,094 users that it is possible to predict from digital footprints of the Facebook users their self-reported addictive tendencies toward social media by applying machine-learning strategies. More specifically, we analyzed the predictive power of a set of models based on different sets of features extracted from digital traces, namely posting activity, language use, and page Likes. To maximize the predictive power of the models, we used an ensemble of linear and non-linear prediction algorithms. This work showed also sufficient accuracy rates in distinguishing between disordered and non-disordered social media users. In sum, individual differences in tendencies toward “social networks use disorder” can be inferred from digital traces left on the social media platform Facebook. Please note that the present work is limited by its cross-sectional design. (shrink)

Individual neurons display characteristic firing patterns determined by the number and kind of ion channels in their membranes. We describe experimental and computational studies that suggest that neurons use activity sensors to regulate the number and kind of ion channels and receptors in their membrane to maintain a stable pattern of activity and to compensate for ongoing processes of degradation, synthesis and insertion of ion channels and receptors. We show that similar neuronal and network outputs can be produced by a (...) number of different combinations of ion channels and synapse strengths. This suggests that individual neurons of the same class may each have found an acceptable solution to a genetically determined pattern of activity, and that networks of neurons in different animals may produce similar output patterns by somewhat variable underlying mechanisms. BioEssays 24:1145–1154, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

The dynamic models are proposed to investigate the influence node activity has on rumor spreading process in both homogeneous and heterogeneous networks. Different from previous studies, we believe that the activity of nodes in complex networks affects the process of rumor spreading. An active node can have contact with all the nodes it directly links to, while an inactive node could only interact with its active neighbors. We explore the joint effort of activity rate, spreading rate (...) and network topology on rumor spreading process by mean-field equations and numerical simulations, which reveals that there exists a critical curve consisting of critical activity rate and spreading rate; meanwhile, activity rate and spreading rate both have influence on the final rumor spreading scale. (shrink)