Distant Links Research Articles

Auditory gamma-band entrainment enhances default mode network connectivity in dementia patients

Dementia, and in particular Alzheimer’s disease (AD), can be characterized by disrupted functional connectivity in the brain caused by beta-amyloid deposition in neural links. Non-pharmaceutical treatments for dementia have recently explored interventions involving the stimulation of neuronal populations in the gamma band. These interventions aim to restore brain network functionality by synchronizing rhythmic energy through various stimulation modalities. Entrainment, a newly proposed non-invasive sensory stimulation method, has shown promise in improving cognitive functions in dementia patients. This study investigates the effectiveness of entrainment in terms of promoting neural synchrony and spatial connectivity across the cortex. EEG signals were recorded during a 40 Hz auditory entrainment session conducted with a group of elderly participants with dementia. Phase locking value (PLV) between different intraregional and interregional sites was examined as an attribute of network synchronization, and connectivity of local and distant links were compared during the stimulation and rest trials. Our findings demonstrate enhanced neural synchrony between the frontal and parietal regions, which are key components of the brain’s default mode network (DMN). The DMN operation is known to be impacted by dementia’s progression, leading to reduced functional connectivity across the parieto-frontal pathways. Notably, entrainment alone significantly improves synchrony between these DMN components, suggesting its potential for restoring functional connectivity.

An improved non-local awareness of congestion and load balanced algorithm for the communication of on chip 2D mesh-based network

Due to advancements in multi-core design technology, IC (Integrated Circuits) designers have expanded the single chip multi-core design. A privileged way of communication effectively between these multi-cores is a Network on-chip (NoC). Design of an effective routing algorithm capable of routing data to non-congested paths is the most notable research challenge in NoC, by retrieving congestion information of non-local nodes. This research proposed an improved congestion-aware load balancing routing algorithm. Non-local or distant links congestion awareness is done by propagating congestion information via data packets. By counting number of hops from the source node, in the quadrant of the destination node, an intermediate node has been defined, and after the calculation of the least congested route to the intermediate node, this route is also stored in the data packet for source routing. Furthermore, for load balancing network is partitioned into two areas called high congested area (HCA) and low congested area (LCA). For load balancing, from HCA a node in LCA is selected as output for data packets. Comparison of the proposed algorithm is done in the form of average latency, average throughput, power consumption, and scalability analysis under synthetic traffic patterns. Under simulation experiments, it is shown improvement in an average latency and throughput of the proposed algorithm is 31.28% and 5.28% respectively, than existing.

Dentofacial dysmorphoses : distant links with musculo-skeletal system and posture

According to several theories, the oro-facial sphere would be interconnected with the rest of the body justifying the requests for care to improve a body zone at a distance. The aim of this literature review was to look for potential distant links of dysmorphoses of the three dimensions of space according to the etiopathogenic theories and the data of science. We carried out a keyword search leading to 58 references. In the transverse dimension, the transverse maxillary hypoplasia and dissymmetry of the molar class of the transverse dimension would not induce a change in the distribution of the weight of the body on a stabilometric platform. In the vertical dimension, hyperdivergent patients have a decreased bite force, cephalic extension with respect to the spine, an extension of the base of the skull, and decreased cervical lordosis. In the anteroposterior dimension, skeletal classesII would be associated with increased cervical lordosis and posterior cephalic extension according to the «true vertical» (inversely for classes III). The prevalence of dental classes II would be increased in scoliosis subjects. Studies with a low level of evidence (grade III, IV or even V) should be interpreted with caution because the simultaneous presence of concomitant anomalies does not allow us to conclude that there is a cause-and-effect relationship.

ECOD: identification of distant homology among multidomain and transmembrane domain proteins

The manual classification of protein domains is approaching its 20th anniversary. ECOD is our mixed manual-automatic domain classification. Over time, the types of proteins which require manual curation has changed. Depositions with complex multidomain and multichain arrangements are commonplace. Transmembrane domains are regularly classified. Repeatedly, domains which are initially believed to be novel are found to have homologous links to existing classified domains. Here we present a brief summary of recent manual curation efforts in ECOD generally combined with specific case studies of transmembrane and multidomain proteins wherein manual curation was useful for discovering new homologous relationships. We present a new taxonomy for the classification of ABC transporter transmembrane domains. We examine alternate topologies of the leucine-specific (LS) domain of Leucine tRNA-synthetase. Finally, we elaborate on a distant homologous links between two helical dimerization domains.

Centralized and distributed cognitive task processing in the human connectome.

A key question in modern neuroscience is how cognitive changes in a human brain can be quantified and captured by functional connectivity (FC). A systematic approach to measure pairwise functional distance at different brain states is lacking. This would provide a straightforward way to quantify differences in cognitive processing across tasks; also, it would help in relating these differences in task-based FCs to the underlying structural network. Here we propose a framework, based on the concept of Jensen-Shannon divergence, to map the task-rest connectivity distance between tasks and resting-state FC. We show how this information theoretical measure allows for quantifying connectivity changes in distributed and centralized processing in functional networks. We study resting state and seven tasks from the Human Connectome Project dataset to obtain the most distant links across tasks. We investigate how these changes are associated with different functional brain networks, and use the proposed measure to infer changes in the information-processing regimes. Furthermore, we show how the FC distance from resting state is shaped by structural connectivity, and to what extent this relationship depends on the task. This framework provides a well-grounded mathematical quantification of connectivity changes associated with cognitive processing in large-scale brain networks.

Visual search task immediate training effects on task-related functional connectivity.

Brain plasticity occurs over the course of the human lifetime. Learning and training modify our neuronal synapses and adapt our brain activity, from priming effects in modal areas to higher-order changes in the association cortex. The current state of the art suggests that learning and training effects might induce large-scale brain connectivity changes. Here, we used task-fMRI data and graph-based approaches to study the immediate brain changes in functional connections associated with training on a visual search task, and the individual differences in learning were studied by means of brain-behavior correlations. In a previous work, we found that trained participants improved their response speed on a visual search task by 31%, whereas the control group hardly changed. In the present study, we showed that trained individuals changed regional connections (local links) in cortical areas devoted to the specific visual search processes and to areas that support information integration, and largely modified distributed connections (distant links) linking primary visual areas to specific attentional and cognitive control areas. In addition, we found that the individuals with the most enhanced connectivity in the dorsolateral prefrontal cortex performed the task faster after training. The observed behavioral and brain connectivity findings expand our understanding of large-scale dynamic readjustment of the human brain after learning experiences.

MCAR: Non-local adaptive Network-on-Chip routing with message propagation of congestion information

Congestion occurs frequently in Networks-on-Chip (NoC) when the packet demands exceed the capacity of network resources. Non-local adaptive routing algorithms utilize the congestion information of both local and distant links to decide the output link selection, which can greatly improve the network performance. The existing non-local adaptive routing algorithms have two mechanisms to propagate the congestion information of distant links. One of mechanism is to increase additional wires/clusters. The other mechanism is to embed the propagated information in packet headers. This paper proposes a new non-local adaptive routing algorithm called MCAR. In MCAR, two special kinds of messages are used to propagate the congestion information of distant links across the network without introducing additional wires/clusters and leading to a better timeliness of congestion information. Moreover, MCAR efficiently utilizes the propagated information to decide the output link selection. Experimental results on both synthetic traffic patterns and application traces show that MCAR achieves better saturation throughput (5.84% on average) and smaller power consumption (7.58% on average) than a state-of-the-art adaptive routing algorithm.

THE VOCABULARY OF TRADES AS THE SOURCE OF RUSSIAN SURNAMES: TANNING INDUSTRY

The article deals with the ability of a derivative word to fix and maintain the knowledge. The formation of new words is always associated with the needs to secure the new object of thought in linguistic form. The structure of derivative contains a reference to the characteristic according to which the subject was realized and allocated among others. Words live in their original meaning as long as their meanings are important for speakers; but when human thought goes further and transfers old meanings to the new items and features, words change. Modern Russian names also used to be derived words with live word -formative links. Naming was carried out for various reasons: with a reference to personal traits, to place of residence, to parents' names and nicknames, as well as with a reference to professional activities. Within the framework of modern Russian anthroponomical system there is a great number of surnames with origins related to the vocabulary of ancient crafts and trades of peasantry. Using written records of various times, the author analyzes a number of Russian surnames within the historic and word-formation aspects. The surnames under consideration are related to the lexical and thematic group of words from the sphere of tanning industry. In the structure of each «professional» surname there are traces of directly motivating units and more distant links of the word-formation chain.

Obsidian Artifacts from East Texas Archaeological Sites

Obsidian artifacts are one of the few material culture remains on East Texas sites that provide direct evidence of distant links between East Texas’s native American peoples and native American communities in the Southwest or the Northwestern Plains. Other such material culture items include marine shells from the Gulf of California, turquoise from New Mexico sources, and sherds from ceramic vessels made in the Puebloan Southwest. Such artifacts, however, are rarely recovered in East Texas archaeological sites. In this article, we summarize the available information on obsidian artifacts from East Texas archaeological sites, much of it gathered from Hester’s Texas Obsidian Project (TOP), including obsidian source data when it is available.

Pictish symbol stones and early cross-slabs from Orkney

Orkney shared in the flowering of interest in stone carving that took place throughout Scotland from the 7th century ad onwards. The corpus illustrated here includes seven accomplished Pictish symbol-bearing stones, four small stones incised with rough versions of symbols, at least one relief-ornamented Pictish cross-slab, thirteen cross-slabs (including recumbent slabs), two portable cross-slabs and two pieces of church furniture in the form of an altar frontal and a portable altar slab. The art-historical context for this stone carving shows close links both with Shetland to the north and Caithness to the south, as well as more distant links with Iona and with the Pictish mainland south of the Moray Firth. The context and function of the stones are discussed and a case is made for the existence of an early monastery on the island of Flotta.

FreeRider: Non-Local Adaptive Network-on-Chip Routing with Packet-Carried Propagation of Congestion Information

Non-local adaptive routing techniques, which utilize statuses of both local and distant links to make routing decisions, have recently been shown to be effective solutions for promoting the performance of Network-on-Chip (NoC). The essence of non-local adaptive routing was an additional network dedicated to propagate congestion information of distant links on the NoC. While the dedicated Congestion Propagation Network (CPN) helps routers to make promising routing decisions, it incurs additional wiring and power costs and becomes an unnecessary decoration when the load of NoC is light. Moreover, the CPN has to be extended if one would utilize more sophisticated congestion information to enhance the performance of NoC, bringing in even larger wiring and power costs. This paper proposes an innovative non-local adaptive routing technique called FreeRider, which does not use a dedicated CPN but instead leverages free bits in head flits of existing packets to carry and propagate rich congestion information without introducing additional wires or flits. In order to balance the network load, FreeRider adopts a novel three-stage strategy of output link selection, which adequately utilizes the propagated information to make routing decisions. Experimental results on both synthetic traffic patterns and application traces show that FreeRider achieves better throughput, shorter latency, and smaller power consumption than a state-of-the-art adaptive routing technique with dedicated CPN.

Testing complex networks of interaction at the onset of the Near Eastern Neolithic using modelling of obsidian exchange.

In this paper, we explore the conditions that led to the origins and development of the Near Eastern Neolithic using mathematical modelling of obsidian exchange. The analysis presented expands on previous research, which established that the down-the-line model could not explain long-distance obsidian distribution across the Near East during this period. Drawing from outcomes of new simulations and their comparison with archaeological data, we provide results that illuminate the presence of complex networks of interaction among the earliest farming societies. We explore a network prototype of obsidian exchange with distant links which replicates the long-distance movement of ideas, goods and people during the Early Neolithic. Our results support the idea that during the first (Pre-Pottery Neolithic A) and second (Pre-Pottery Neolithic B) phases of the Early Neolithic, the complexity of obsidian exchange networks gradually increased. We propose then a refined model (the optimized distant link model) whereby long-distance exchange was largely operated by certain interconnected villages, resulting in the appearance of a relatively homogeneous Neolithic cultural sphere. We hypothesize that the appearance of complex interaction and exchange networks reduced risks of isolation caused by restricted mobility as groups settled and argue that these networks partially triggered and were crucial for the success of the Neolithic Revolution. Communities became highly dynamic through the sharing of experiences and objects, while the networks that developed acted as a repository of innovations, limiting the risk of involution.

New Metric for HWMP Protocol (NMH)

The IEEE 802.11s Wireless Mesh Networks (WMN) is a new multi -hop technology increasing the coverage of IEEE 802.11 Wireless Network and providing Internet access. Recently, many researchers proposed several metric routing protocols for wireless mesh networks(WMNs). Some metrics consider the interferences and other study the channel diversity of the distant links along the path between the source and the destination. In order to provide the best path between the source and the destination, this paper proposes a new routing metric named (NMH) New Metric for Hybrid Wireless Mesh Protocol(HWMP). NMH is based on two hop channel diversity and hop delay. The simulation results show that NMH out performs WCETT in terms of average network throughput, end -to-end delay and number of flows.

Considering baseline homophily when generating spatial social networks for agent-based modelling

Social networks have become an important part of agent-based models, and their structure may have remarkable impact on simulation results. We propose a simple and efficient but empirically based approach for spatial agent-based models which explicitly takes into account restrictions and opportunities imposed by effects of baseline homophily, i.e. the influence of local socio-demography on the composition of one's social network. Furthermore, the algorithm considers the probability of links that depends on geographical distance between potential partners. The resulting network reflects social settings and furthermore allows the modeller to influence network properties by adjusting agent type specific parameters. Especially the parameter for distance dependence and the probability of distant links allow for control of clustering and agent type distribution of personal networks.

Discourse style and theme–rheme progression in biomedical research article discussions

This paper examines the Discussions of Spanish medical research articles and Spanish translations of comparable English-language texts in order to determine how far their discourse and theme–rheme patterns differ. Quantitative analysis revealed two discourse patterns. Spanish authors preferred a progressive style characterized by considerable initial background information, and a commentary opening with a statement of result and ending with the main claim. In contrast, most translations exhibited a retrogressive style with little or no background information, and the main claim located early or at the start. The Spanish texts showed a highly cohesive thematic pattern, most within-paragraph links being with the immediately preceding theme or rheme, whereas the translations, influenced by the source texts, contained comparatively more distant links, thus creating thematic ‘jumps’. Thematic progression was independent of discourse pattern. Qualitative analysis identified a number of strategies that can help translators align their texts with the target language norm for theme–rheme progression.

Comparative analysis of the virulence of invertebrate and mammalian pathogenic bacteria in the oral insect infection model Galleria mellonella

Infection of Galleria mellonella by feeding a mixture of Bacillus thuringiensis spores or vegetative bacteria in association with the toxin Cry1C results in high levels of larval mortality. Under these conditions the toxin or bacteria have minimal effects on the larva when inoculated separately. In order to evaluate whether G. mellonella can function as an oral infection model for human and entomo-bacterial pathogens, we tested strains of Bacillus cereus, Bacillus anthracis, Enterococcus faecalis, Listeria monocytogenes, Pseudomonas aeruginosa and a Drosophila targeting Pseudomonas entomophila strain . Six B. cereus strains (5 diarrheal, 1 environmental isolate) were first screened in 2nd instar G. mellonella larvae by free ingestion and four of them were analyzed by force-feeding 5th instar larvae. The virulence of these B. cereus strains did not differ from the B. thuringiensis virulent reference strain 407Cry − with the exception of strain D19 (NVH391/98) that showed a lower virulence. Following force-feeding, 5th instar G. mellonella larvae survived infection with B. anthracis, L. monocytogenes, E. faecalis and P. aeruginosa strains in contrast to the P. entomophila strain which led to high mortality even without Cry1C toxin co-ingestion. Thus, specific virulence factors adapted to the insect intestine might exist in B. thuringiensis/ B. cereus and P. entomophila. This suggests a co-evolution between host and pathogens and supports the close links between B. thuringiensis and B. cereus and more distant links to their relative B. anthracis.

Developing Biotechnology Clusters in Non‐high Technology Regions—The Case of Austria

This paper explores the role of distant knowledge links and policy actions for the development of biotechnology clusters. It seeks to challenge the prevailing view that the birth and early development of high technology industries are always spontaneous phenomena which are mainly based on local knowledge. Departing from the theoretical concept of regional innovation systems (RIS), a distinction between “RIS with strong potentials for high technology industries” and “RIS with weak potentials for high technology industries” will be drawn. It will be argued that in the latter case the development of biotechnology clusters is more dependent on distant knowledge sources and proactive policy efforts to create a favourable environment for high technology activities. Furthermore, it will be shown that a far‐reaching transformation of the regional innovation system is crucial for catching‐up processes of regions which are latecomers in high technology sectors such as biotechnology.

Third‐order transport due to internal waves and non‐local turbulence in the stably stratified surface layer

AbstractUntil recently the concern of the traditional theory of the atmospheric stable boundary layer (SBL) was, almost without exception, the nocturnal SBL developing after sunset on the background of a neutral or slightly stable residual layer. In the nocturnal SBLs the nature of turbulence is basically local. Its lower portion is well described by the classical Monin–Obukhov surface‐layer similarity theory. Things are different in long‐lived SBLs situated immediately below the stably stratified free flow. Here, the surface‐layer turbulence is affected by the free‐flow Brunt–Väisälä frequency, N. The surface layer represents approximately one‐tenth of the SBL, so that it is separated from the free atmosphere by the upper nine‐tenths of the SBL comprising hundreds of metres. Traditional concepts fail to explain such distant links. Zilitinkevich and Calanca extended the traditional Monin–Obukhov similarity theory by including N in the surface‐layer scaling, and provided experimental evidence in support of this extension. In the present paper, physical mechanisms responsible for non‐local features of the long‐lived SBL turbulence are identified as: radiation of internal waves from the SBL upper boundary to the free atmosphere, and the internal‐wave transport of the squared fluctuations of velocity and potential temperature. The third‐order wave‐induced fluxes are included in an advanced turbulence‐closure model to correct the wind and temperature profiles in the surface layer. The model explains why developed turbulence in the surface layer can exist at much larger Richardson numbers than the classical theory predicts. Results from the new model are in good agreement with the extended similarity theory and experimental data. Copyright © 2002 Royal Meteorological Society.

Supplement to ‘Third‐order transport due to internal waves and non‐local turbulence in the stably stratified surface layer’

AbstractA linear theory of internal gravity waves (IGWs) is applied to consider the IGW‐induced vertical fluxes of kinetic energy, pressure and squared density (or buoyancy) in non‐turbulent stably stratified fluid characterized by the Brunt–Väisälä frequency, N. These fluxes are required in modelling distant links and non‐local transports in the atmosphere. Investigations of the vertical flux of kinetic energy have shown that this flux, caused by the wave component performing the most efficient vertical transport, is proportional to N3. As far as the authors know, the flux of the squared density fluctuations was not systematically investigated. It is shown to be proportional to N5. Copyright © 2002 Royal Meteorological Society.

Improved Hamiltonian lattice gauge theory

We derive an improved lattice Hamiltonian for pure gauge theory, coupling arbitrarily distant links in the kinetic term. The level of improvement achieved is examined in variational calculations of the SU(2) specific heat in 2+1 dimensions.