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As the signaling processing center of 5G, the security and stability of the 5G Core Network (5GC) are of great importance for 5G. The current 5GC consists of multiple mutually independent Network Functions (NFs). However, the NF service access procedure does not match NF service requests and business processes. NFs can request authorized services for access at any time, which poses a security threat to NFs and user data. This paper proposes a security enhancement scheme for NF service access procedures based on the business process, which realizes the management of the NF business process. The NRF adds a token identifier field bound to the business process in the access token and establishes an access token repository to store the token identifier. NF Service Producer introduces an access token re-signature mechanism and a shared repository of responded access tokens. The security of the proposed scheme is verified by theoretical analysis and formal analysis, and the performance of the proposed scheme is evaluated in terms of response rate and resource consumption. The experimental results show that the proposed scheme can meet the security requirement with little efficiency degradation under the condition of increasing certain resource loss. [ABSTRACT FROM AUTHOR]

In this paper we continue our study of path discovery process for Service Function Chaining (SFC) in Software Defined Network (SDN). By default, service function (SF) paths are established proactively - before data transmission takes place. We have argued that this constraint can be eliminated with the use of our proposed Reactive SF path discovery approach. Such SFs as network address translation (NAT) or stateful firewall (FW) are SF path’s symmetry dependent requiring a visit of both ingress and egress flows. Thus, we evaluated SF path discovery processes in Mininet emulation network. Outcome of this study is a comparison of proactive and reactive SF path discovery processes for both asymmetrical and symmetrical SF paths. It shows that even in symmetrical environment reactive SF path discovery has a higher probability of successful SF path detection.

Summary: Fog computing allows for local data processing at the edge of the network. This allows for reduced link delays between mobile users and access points. Here, fog nodes are collocated with radio remote heads (RRHs) to provide local processing capabilities, that is, creating fog radio access network (F‐RAN) that can support ultralow latency for cellular networks that operate on millimeter wave (mmWave) bands. Here, mobile stations (MS) demand various network functions (NFs) that correspond to different service requests. Hence, it is critical to study function popularity and allow content caching at the F‐RAN. Given the limited resources at the fog nodes, it is important to efficiently manage the resources to improve network operations and enhance the capacity at reduced delays and cost. Therefore, caching in mmWave F‐RAN requires node allocation that can accommodate the highest number of cached functions. Hence, this paper proposes a novel node placement scheme that leverages Nelder–Mead meta‐heuristic. Results show that the proposed scheme yields in reduced delay, cost, and power and energy consumption. [ABSTRACT FROM AUTHOR]

Zur sprachlichen Verständigung und Partizipation an den Versorgungsstrukturen des Sozial- und Gesundheitswesens bei Menschen mit Sprachbarrieren und einem Migrations- oder Fluchthintergrund entwickelte sich der Tätigkeitsbereich der Sprach- und Integrationsmittler/-in in Abgrenzung zum/zur Dolmetscher/-in. Im Rahmen des Forschungsprojektes RundUm begleiteten Sprach- und Integrationsmittlerinnen des Sprachmittlerdienstes SprInt in Essen Schwangere und junge Mütter zu Terminen der Regelversorgung im Gesundheitswesen. Die Chancen und Herausforderungen innerhalb der geburtshilflichen Versorgung aus Sicht der Sprach- und Integrationsmittlerinnen sind Gegenstand der vorliegenden Studie.

Fog-radio access networks (F-RANs) alleviate fronthaul delays for cellular networks as compared to their cloud counterparts. This allows them to be suitable solutions for networks that demand low propagation delays. Namely, they are suitable for millimeter wave (mmWave) operations that suffer from short propagation distances and possess a poor scattering environment (low channel ranks). The F-RAN here is comprised of fog nodes that are collocated with radio remote heads (RRHs) to provide local processing capabilities for mobile station (MS) terminals. These terminals demand various network functions (NFs) that correspond to different service requests. Now, provisioning these NFs on the fog nodes also yields service delays due to the requirement for service migration from the cloud, i.e., offloading to the fog nodes. One solution to reduce this service delay is to provide cached copies of popular NFs in advance. Hence, it is critical to study function popularity and allow for content caching at the F-RAN. This is further a necessity given the limited resources at the fog nodes, thus requiring efficient resource management to enhance network capacity at reduced power and cost penalty. This paper proposes novel solutions that allocate popular NFs on the fog nodes to accelerate services for the terminals, namely, the clustered and distributed caching methods. The two methods are analyzed and compared against the baseline uncached provisioning schemes in terms of service delay, energy consumption, and cost. [ABSTRACT FROM AUTHOR]

The adoption of network traffic encryption is continually growing. Popular applications use encryption protocols to secure communications and protect the privacy of users. In addition, a large portion of malware is spread through the network traffic taking advantage of encryption protocols to hide its presence and activity. Entering into the era of completely encrypted communications over the Internet, we must rapidly start reviewing the state-of-the-art in the wide domain of network traffic analysis and inspection, to conclude if traditional traffic processing systems will be able to seamlessly adapt to the upcoming full adoption of network encryption. In this survey, we examine the literature that deals with network traffic analysis and inspection after the ascent of encryption in communication channels. We notice that the research community has already started proposing solutions on how to perform inspection even when the network traffic is encrypted and we demonstrate and review these works. In addition, we present the techniques and methods that these works use and their limitations. Finally, we examine the countermeasures that have been proposed in the literature in order to circumvent traffic analysis techniques that aim to harm user privacy. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of solving Seal's type partial integro-differential equations (PIDEs) for the classical compound Poisson risk model. A data-driven deep neural network (DNN) method is proposed to calculate finite-time survival probability, and an alternative scheme is also investigated when claim payments are exponentially distributed. The DNN method is then extended to the numerical solution of generalized PIDEs. Numerical approximation results under different claim distributions are given, which show that the proposed scheme can obtain accurate results under different claim distributions. [ABSTRACT FROM AUTHOR]

Over the last few decades, various adsorption functions of polymer hydrogels for the removal of hazardous pollutants have been developed. The performance of hydrogel adsorbents depends on the constituents of the gels and the functions produced by the polymer networks of the gels. Research on hydrogels utilizing the characteristic functions of polymer networks has increased over the last decade. The functions of polymer networks are key to the development of advanced adsorbents for the removal of various pollutants. No review has discussed hydrogel adsorbents from the perspective of the roles and functions of polymer networks in hydrogels. This paper briefly reviews the basic requirements of adsorbents and the general characteristics of hydrogels as adsorbents. Thereafter, hydrogels are reviewed on the basis of the roles and functions of the polymer networks in them for the removal of hazardous pollutants by introducing studies published over the last decade. The application of hydrogels as adsorbents for the removal of hazardous pollutants is discussed as well. [ABSTRACT FROM AUTHOR]

Early in the postnatal period, motoneuron axon stimulation can excite motor networks in the spinal cord. Here we tested if these excitatory effects changed across early postnatal development up to postnatal day (P) 24 by when mice are capable of weight-bearing locomotion and locomotor networks are considered functionally mature. This was accomplished in the isolated spinal cord preparation using ventral root evoked entrainment of disinhibited bursts. Ventral root evoked entrainment was defined and characterized over the first 2 weeks of postnatal development, and was found to decline over this period, but entrainment could still be detected in mice as old as P24. Disinhibited bursting could be elicited, and dorsal root evoked entrainment could be recorded as late as P39 and remained unchanged in effectiveness, suggesting that poor tissue viability may not be the cause of the decline in ventral root evoked entrainment. Pharmacological experiments performed on younger animals established that dopamine D2 receptor antagonists and mGluR1 agonists both enhanced ventral root evoked entrainment. In conclusion, the motoneuronal inputs to spinal motor networks via the excitatory pathway is modulated by dopamine and metabotropic glutamate receptors and may be under powerful inhibitory control, which may explain why there is a developmental decline in entrainment.

Astrocytes are recognized as more important cells than historically thought in synaptic function through the reciprocal exchange of signaling with the neuronal synaptic elements. The idea that astrocytes are active elements in synaptic physiology is conceptualized in the Tripartite Synapse concept. This review article presents and discusses recent representative examples that highlight the heterogeneity of signaling in tripartite synapse function and its consequences on neural network function and animal behavior. [ABSTRACT FROM AUTHOR]

Abstract Major depressive disorder (MDD) is a debilitating chronic illness that is two times more prevalent in women than in men. The mechanisms associated with the increased female susceptibility to depression remain poorly characterized. Aberrant neuronal oscillatory activity within the putative depression network is an emerging mechanism underlying MDD. However, innate sex differences in network activity and its contribution to depression vulnerability have not been well described. In this review, current evidence of sex differences in neuronal oscillatory activity, including the influence of sex hormones and female cycling, will first be described followed by evidence of disrupted neuronal circuit function in MDD and the effects of antidepressant treatment. Lastly, current knowledge of sex differences in MDD-associated aberrant circuit function and oscillatory activity will be highlighted, with an emphasis on the role of sex steroids and female cycling. Collectively, it is clear that there are significant gaps in the literature regarding innate and pathologically associated sex differences in network activity and that the elucidation of these differences is invaluable to our understanding of sex-specific vulnerabilities and therapies for MDD.

Fog-radio access networks (F-RANs) alleviate fronthaul delays for cellular networks as compared to their cloud counterparts. This allows them to be suitable solutions for networks that demand low propagation delays. Namely, they are suitable for millimeter wave (mmWave) operations that suffer from short propagation distances and possess a poor scattering environment (low channel ranks). The F-RAN here is comprised of fog nodes that are collocated with radio remote heads (RRHs) to provide local processing capabilities for mobile station (MS) terminals. These terminals demand various network functions (NFs) that correspond to different service requests. Now, provisioning these NFs on the fog nodes also yields service delays due to the requirement for service migration from the cloud, i.e., offloading to the fog nodes. One solution to reduce this service delay is to provide cached copies of popular NFs in advance. Hence, it is critical to study function popularity and allow for content caching at the F-RAN. This is further a necessity given the limited resources at the fog nodes, thus requiring efficient resource management to enhance network capacity at reduced power and cost penalty. This paper proposes novel solutions that allocate popular NFs on the fog nodes to accelerate services for the terminals, namely, the clustered and distributed caching methods. The two methods are analyzed and compared against the baseline uncached provisioning schemes in terms of service delay, energy consumption, and cost.

In this paper, we study the problem of solving Seal’s type partial integro-differential equations (PIDEs) for the classical compound Poisson risk model. A data-driven deep neural network (DNN) method is proposed to calculate finite-time survival probability, and an alternative scheme is also investigated when claim payments are exponentially distributed. The DNN method is then extended to the numerical solution of generalized PIDEs. Numerical approximation results under different claim distributions are given, which show that the proposed scheme can obtain accurate results under different claim distributions.

Over the last few decades, various adsorption functions of polymer hydrogels for the removal of hazardous pollutants have been developed. The performance of hydrogel adsorbents depends on the constituents of the gels and the functions produced by the polymer networks of the gels. Research on hydrogels utilizing the characteristic functions of polymer networks has increased over the last decade. The functions of polymer networks are key to the development of advanced adsorbents for the removal of various pollutants. No review has discussed hydrogel adsorbents from the perspective of the roles and functions of polymer networks in hydrogels. This paper briefly reviews the basic requirements of adsorbents and the general characteristics of hydrogels as adsorbents. Thereafter, hydrogels are reviewed on the basis of the roles and functions of the polymer networks in them for the removal of hazardous pollutants by introducing studies published over the last decade. The application of hydrogels as adsorbents for the removal of hazardous pollutants is discussed as well.

Recently, the present authors’ research group derived an analytical expression to link the harmonic sum of the squares of short circuit natural frequencies (SCNFs) of a single, isolated winding to its elementary inductances and capacitances. Also, it was demonstrated how this expression could be practically used for locating radial and axial displacements, along with assessing its severity on a single, isolated, actual transformer winding. The next logical task was to extend the derived expression to multi-phase windings, viz., star/delta connections and for any terminal condition of the neutral. Actually, it would be desirable to have a similar expression for open circuit natural frequency (OCNF) as well. A major highlight of this paper is that it presents a single, unified approach (using salient features of coefficients of the numerator and denominator polynomial of driving-point impedance) by which compact analytical expressions can be simultaneously derived for both SCNF and OCNF, for any multi-phase transformer configuration, and for any condition of the neutral terminal. Complete derivation details of the proposed method are presented, and then, the expressions for SCNF and OCNF are derived for 1- $\Phi$ isolated windings as well as 3- $\Phi$ (Y, $\Delta$) configurations. Finally, simulation results for all the cases are reported. [ABSTRACT FROM AUTHOR]

Balancing the Spatial structure and determining the future urban network are the fundamental missions of spatial planning. As the main organizing elements of space, cities are organized within the urban network form. Urban network is assessed based on the agreement between form and function dimensions. The effectiveness of various models can be investigated through an analysis of their relationships. Accordingly, the study at hand has been carried out to analyze the urban morphology in order to accord the morphological and functional dimensions of Hormozgan province urban network. The study is applied in terms of purpose and descriptiveanalytical in terms of methodology. The analytic indices of the study for Hormozgan province urban network morphology include road network, the distance between settlements, urban population, and types of services. The analytic instrument for the attainment of the purpose of the study is the Inward Distance Weighted (IDW) model within ARC GIS 10-4 software. The obtained results show that Hormozgan province urban network morphology follows four patterns, namely mono-centric, polycentric, linear and isolated. The location of these patterns in the province indicates the relationship between the location and the network morphology. As the large cities of the province are located near the sea, the mono-centric and polycentric patterns have been formed under the influence of the sea factor. However, the isolated and linear patterns are located in both the islands of the province and the mountainous areas or intermountain plateaus. Ultimately, the study shows that the lack of agreement between the form and the function weakens the connection and interaction of the interconnected areas. This lack of agreement reduces the fulfillment of the urban network’s use of neighboring opportunities and decreases the network effectiveness. [ABSTRACT FROM AUTHOR]

• We studied how landscape affect both the structure and function of seed dispersal networks in different fragmented habitats. • Increasing landscape fragmentation lead to a reduction in the structure of seed dispersal networks. • The value of seed dispersal potential was highest in the medium levels of fragmented habitat. Forest fragmentation has resulted in reduced natural habitats and alterations in landscape structure. Although the effects of landscape features on the structure of seed dispersal networks are well known, the effects on functional consequences of these networks remain unclear. In this study, we compared the structures of seed dispersal networks of three fragmented habitats (high-, medium-, and low-fragmented habitats). We used an integrative index (seed dispersal potential, SDP) to evaluate the network functions of the three habitats. We also studied how the structure and function of seed dispersal networks respond to different landscape features. Approximately 23, 26, and 22 bird species were recorded foraging for 9, 25, and 22 plant species, resulting in 315, 665, and 546 foraging events in high-, medium-, and low-fragmentation habitats, respectively. The structure and function of seed dispersal networks of the three fragmented habitats significantly differ. For instance, the network in a highly fragmented habitat exhibits high connectance and nestedness, whereas the network in a low-fragmentation habitat exhibits high modularity and specialization. Furthermore, the network function (the SDP value for frugivorous species) varies for each habitat. Frugivorous species exhibit a lower seed dispersal potential in highly fragmented habitats, as indicated by their low total SDP values. Most importantly, the structure and function of the seed dispersal network are differently affected by landscape variables. Increasing habitat fragmentation leads to a reduction in the structure of seed dispersal networks. However, medium levels of fragmentation can enhance the network function. Overall, our study highlights the importance of considering both structural and functional aspects of mutualistic networks to understand the landscape effects of habitat fragmentation. The SDP index provides a comprehensive approach to study the functions of mutualistic networks and is a useful tool for future forest management. [ABSTRACT FROM AUTHOR]

This work introduces a methodology for the modelization of network functions focused on the identification of recurring execution patterns as basic building blocks and aimed at providing a platform independent representation. By mapping each modeling building block on specific hardware, the performance of the network function can be estimated in terms of maximum throughput that the network function can achieve on the specific execution platform. The approach is such that once the basic modeling building blocks have been mapped, the estimate can be computed automatically for any modeled network function. Experimental results on several sample network functions show that although our approach cannot be very accurate without taking in consideration traffic characteristics, it is very valuable for those application where even loose estimates are key. One such example is orchestration in network functions virtualization (NFV) platforms, as well as in general virtualization platforms where virtual machine placement is based also on the performance of network services offered to them. Being able to automatically estimate the performance of a virtualized network function (VNF) on different execution hardware, enables optimal placement of VNFs themselves as well as the virtual hosts they serve, while efficiently utilizing available resources. [ABSTRACT FROM AUTHOR]

By forming city-to-city (C2C) transnational networks, cities can take action collectively against climate change. Interaction and collaboration among cities offers policymakers a chance to learn how other cities are conducting climate mitigation and adaptation measures. However, activities of C2C climate networks vary. By analyzing C2C climate networks, this study aims to identify and categorize C2C networks for climate change action, and to link the functions with levels of activity. To understand C2C climate-action networks, we suggest a framework for mapping C2C: geographic bases (domestic, regional, and global C2C), linking modalities (multilateral, and institution-led C2C), and functions (information exchange, networking, lobbying and funding, research, standards and commitments provision, and monitoring and certification). Based on this framework, we analyze the contents of C2C websites to assess current activities. We find that not all C2C networks are currently active. Statistical analysis and case studies suggest that C2C climate networks with advanced functions—such as lobbying, research, climate plans, and monitoring—are likely to actively engage with member cities. However, C2C cooperation focusing mainly on networking or information sharing is less likely to survive. Policy implications suggest that well-designed and advanced C2C networks with research and monitoring functions rather than simple networking functions can enable member cities to actively engage in climate policy cooperation. [ABSTRACT FROM AUTHOR]

In the recent years, telecom and computer networks have witnessed new concepts and technologies through Network Function Virtualization (NFV) and Software-Defined Networking (SDN). SDN, which allows applications to have a control over the network, and NFV, which allows deploying network functions in virtualized environments, are two paradigms that are increasingly used for the Internet of Things (IoT). This Internet (IoT) brings the promise to interconnect billions of devices in the next few years rises several scientific challenges in particular those of the satisfaction of the quality of service (QoS) required by the IoT applications. In order to address this problem, we have identified two bottlenecks with respect to the QoS: the traversed networks and the intermediate entities that allows the application to interact with the IoT devices. In this paper, we first present an innovative vision of a “network function” with respect to their deployment and runtime environment. Then, we describe our general approach of a solution that consists in the dynamic, autonomous, and seamless deployment of QoS management mechanisms. We also describe the requirements for the implementation of such approach. Finally, we present a redirection mechanism, implemented as a network function, allowing the seamless control of the data path of a given middleware traffic. This mechanism is assessed through a use case related to vehicular transportation. [ABSTRACT FROM AUTHOR]

During development of the spinal cord, a precise interaction occurs between descending projections and sensory afferents, with spinal networks that lead to expression of coordinated motor output. In the rodent, during the last embryonic week, motor output first occurs as regular bursts of spontaneous activity, progressing to stochastic patterns of episodes that express bouts of coordinated rhythmic activity perinatally. Locomotor activity becomes functionally mature in the 2nd postnatal wk and is heralded by the onset of weight-bearing locomotion on the 8th and 9th postnatal day. Concomitantly, there is a maturation of intrinsic properties and key conductances mediating plateau potentials. In this review, we discuss spinal neuronal excitability, descending modulation, and afferent modulation in the developing rodent spinal cord. In the adult, plastic mechanisms are much more constrained but become more permissive following neurotrauma, such as spinal cord injury. We discuss parallel mechanisms that contribute to maturation of network function during development to mechanisms of pathological plasticity that contribute to aberrant motor patterns, such as spasticity and clonus, which emerge following central injury. [ABSTRACT FROM AUTHOR]

Industrial control systems (ICS) represent a major component of our critical infrastructure. With the increasing need for more control and monitoring of such systems, ICS have seen an increase in connectivity to wide area networks (WAN) exposing aging equipment to rapidly evolving cybersecurity threats. Furthermore, the ICS data requires a reliability measure from the networks for critical functions for infrastructure monitoring and control. Especially when remote plant sites are involved such as pipelines, energy distribution networks, and transportation, WAN transport impairments most often provide a best effort delivery with no strict reliability guarantees. Network functions can provide a vendor agnostic, programmable critical infrastructure protection with a single maintenance, policy determination, and reliability assurance surface. A network function (NF) can be utilized for policy enforcement over the communication between remote entities and the main control office. This paper presents the research on transparent integration with existing ICS without disrupting communications, resulting in minimal downtime while decoupling the fast paced evolution of defensive security measures from the upgrade cycle of expensive long term hardware. We report our measurements on the resource requirements and overhead in the network for successful NF insertion under a wide variety of network impairments (network packet delay, reordering, and loss). Our paired NF implementation provides a policy enforcement platform extensible to cover myriad cybersecurity-related communication goals, including packet signing for verification, encryption for data privacy, packet filtering and data diode operation (i.e. protecting against eavesdropping, packet injection, and denial-of-service). Furthermore, bundling communication specifications into packet flows allows for tunability in applying policies as coarse- or fine-grained as the needs of the operator. We report on network function resource requirements in the form of required queue depth and network utilization overhead. [ABSTRACT FROM AUTHOR]

Background: The mitochondrial GTPase mitofusin-2 (MFN2) gene encodes a mitochondrial membrane protein that can induce apoptosis of hepatocellular carcinoma (HCC) via the mitochondrial apoptotic pathway, as validated in our previous research. However, little is known of the clinical significance of MFN2 expression and its signaling pathways in HCC. Methods: MFN2 mRNA expression in tumor and adjacent non-tumor tissues from 115 patients with HCC was investigated using quantitative real-time PCR. The association of the MFN2 mRNA expression level with clinical and pathological parameters was evaluated statistically, while a comparative microarray analysis was used to identify MFN2 signaling pathways in HepG2 cells. Results: MFN2 was significantly (p < 0.0001) downregulated in HCC tissues. Low MFN2 expression was significantly correlated with sex and preoperative alpha-fetoprotein (p < 0.05). Both a Kaplan--Meier survival curve and multivariate analyses showed that MFN2 was related to overall survival. A comparative gene expression microarray revealed 211 upregulated (58 %) and 153 downregulated (42 %) genes. Eighteen pathways were identified as the most significant pathways correlated with MFN2. Conclusions: Low MFN2 expression in HCC indicated a worse overall survival. Crucial signaling molecules such as PI3K-AKT, cytokine receptor, and focal adhesion may participate in MFN2-mediated signaling pathway changes in HCC. [ABSTRACT FROM AUTHOR]

Living cells can maintain their internal states, react to changing environments, grow, differentiate, divide, etc. All these processes are tightly controlled by what can be called a regulatory program. The logic of the underlying control can sometimes be guessed at by examining the network of influences amongst genetic components. Some associated gene regulatory networks have been studied in prokaryotes and eukaryotes, unveiling various structural features ranging from broad distributions of out-degrees to recurrent “motifs”, that is small subgraphs having a specific pattern of interactions. To understand what factors may be driving such structuring, a number of groups have introduced frameworks to model the dynamics of gene regulatory networks. In that context, we review here such in silico approaches and show how selection for phenotypes, i.e., network function , can shape network structure . [ABSTRACT FROM AUTHOR]