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Summary The rapid evolution of user equipment (UE) and 5G networks drives significant transformations, bringing technology closer to end‐users. Managing resources in densely crowded areas such as airports, train stations, and bus terminals poses challenges due to diverse user demands. Integrating mobile edge computing (MEC) and network function virtualization (NFV) becomes vital when the service provider's (SP) primary goal is maximizing profitability while maintaining service level agreement (SLA). Considering these challenges, our study addresses an online resource allocation problem in an MEC network where computing resources are limited, and the SP aims to boost profit by securely admitting more UE requests at each time slot. Each UE request arrival rate is unknown, and the requirement is specific resources with minimum cost and delay. The optimization problem objective is achieved by allocating resources to requests at the MEC network in appropriate cloudlets, utilizing abandoned instances, reutilizing idle and soft slice instances to shorten delay and reduce costs, and immediately scaling inappropriate instances, thus minimizing the instantiation of new instances. This paper proposes a deep reinforcement learning (DRL) method for request prediction and resource allocation to mitigate unnecessary resource waste. Simulation results demonstrate that the proposed approach effectively accepts network slice requests to maximize profit by leveraging resource availability, reutilizing instantiated resources, and upholding goodwill and SLA. Through extensive simulations, we show that our proposed DRL‐based approach outperforms other state‐of‐the‐art techniques, namely, MaxSR, DQN, and DDPG, by 76%, 33%, and 23%, respectively. [ABSTRACT FROM AUTHOR]

Objective: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. This study investigated the structural and functional properties of NAc in patients with BN. Method: Based on the resting‐state functional MRI and high‐resolution anatomical T1‐weighted imaging data acquired from 43 right‐handed BN patients and 40 sex‐, age‐ and education‐matched right‐handed healthy controls (HCs), the group differences in gray matter volume (GMV) and fractional amplitude of low‐frequency fluctuation (fALFF) in slow‐4 and ‐5 bands and functional connectivity (FC) of NAc subregions (core and shell) were compared. The relationships between MRI and clinical data were explored in the BN group. Results: Compared with HCs, BN patients showed preserved GMV, decreased fALFF in slow‐5 band of the left NAc core and shell, decreased FC between left NAc core and right caudate, and increased FC between all NAc subregions and frontal regions, between all NAc subregions (except the right NAc core) and the supramarginal gyrus (SMG), and between right NAc shell and left middle temporal gyrus. FC between the NAc and SMG was correlated with emotional eating behaviors. Discussion: Our study revealed preserved GMV, local neuronal activity reduction and functional network reorganization of the NAc in BN. The functional network reorganization of the NAc mainly occurred in the frontal cortex and was correlated with emotional eating behavior. These findings may provide novel insights into the BN using NAc as an entry point. Public significance: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. We used a multimodal MRI technique to systematically investigate structural and functional alterations in NAc subregions of BN patients and explored the associations between such alterations and maladaptive eating behaviors, hoping to provide novel insights into BN. [ABSTRACT FROM AUTHOR]

With the expansion of internet of things (IoT), the IP‐based network architecture has been difficult to support the development of IoT. Content‐centric mobile networking (CCMN) models are based on naming the content to get rid of address‐space scarcity, caching the content at intermediate nodes to provide efficient data delivery, which can solve the development bottleneck of IoT. The in‐network caching is a key factor to enable practical deployments of CCMN. And it is also subject to serious security threats of cache pollution attacks (CPA), which can tamper the distribution of content and reduce the advantages of built‐in cache. In addition, the identity and trust mechanism of mobile devices are also important factors hindering the deployment of CCMN. However, existing caching security mechanisms cannot be applied directly, because the features of the built‐in cache, including ubiquity, mobility, and heterogeneity, bring new challenges on designing the caching security mechanism against CPA. In this article, we propose a lightweight CPA detection and defense approach for CCMN. We first model the attack and defense process of CPA as a dynamic game, which can optimize the performance of the attack detection. Then, we adopt popularity analysis to detect CPA, and accurately estimate the current network and attack state by a logical regression algorithm. Our design can also intelligently maintain the identity and trust mechanism. Finally, we design a punishment mechanism to deal with the attackers. Extensive simulations demonstrate that our approach can detect CPA efficiently, mitigate the impact of CPA effectively. Our game model can reduce the impact of locality‐disruption attack and false‐locality attack by 60% and 30%, respectively, compared with the state‐of‐the‐art methods. When the game reaches Nash equilibrium, our model can reduce the impact of CPA on cache hit ratio by 55% on average. [ABSTRACT FROM AUTHOR]

Alcohol dependence (AD) is a chronic and relapsing disorder. Conditioned cues associated with the rewarding properties of drugs could trigger motivational/physiological reactions and render subjects vulnerable to relapse. Striatal circuit dysfunction has been implicated in alcohol addiction behaviours. However, little is known about the striatal tracts structural connectivity changes underlying cue induced reactivity in AD. In our present study, we recruited 51 patients with AD; 31 individuals had physiological response. We used seed‐based classification by probabilistic tractography with nine target masks to explore the white matter integrity of striatal circuits in physiological responders (N = 31), non‐responders (N = 20), and healthy controls (N = 27). Compared with healthy controls, physiological responders showed lower fractional anisotropy (FA) and/or higher mean diffusivity in the striatum‐dorsolateral prefrontal cortex (dlPFC), striatum‐ventral lateral prefrontal cortex, striatum‐supplementary motor area (SMA), and striatum‐insular. Considering age and smoking are potential nuisances to diffusion parameters, an analysis of covariance also was conducted and similar results were found. We also found the cue‐induced physiological response was negatively associated with the FA of the striatum‐SMA (r = −0.287; p = 0.045) and left striatum‐dlPFC (r = −0.253; p = 0.079) in AD. In our study, we found abnormal integrity of striatal circuit structural connectivity in AD with physiological cue reactivity, especially trajectory from prefrontal cortex and insular. We also found the FA of striatal tracks was negatively associated with the degree of cue reactivity. Our findings provide further evidence for reduced white matter integrity of striatal circuits for cue reactivity in male individuals with AD. [ABSTRACT FROM AUTHOR]

The Chuan‐Dian Block (CDB) is located in the southeastern margin of the Tibetan Plateau, with a complex geological structure and active regional faults. The present tectonic condition with strong crustal deformation is closely related to the ongoing collision of the India and Eurasia plates since 65 Ma. The study of the crustal structure of this area is key to revealing the evolution and deep geodynamics of the lateral collision zone of the Tibetan Plateau. Deep seismic sounding is the most efficient method with which to unravel the velocity structure of the whole crust. Since the 1980s, 19 deep seismic sounding profiles have been captured within the CDB area. In this study, we systematically integrate the research results of the 19 profiles in this area, then image the 3D crustal velocity, by sampling with a 5 km spacing and 2D/3D Kriging interpolation. The results show the following. (1) The Moho depth in the study area deepens from 30 km in the south to 66 km in the north, whereas there is no apparent variation from west to east. The Pn wave velocity is higher in stable tectonic units, such as 7.95 km/s in the Lanping‐Simao block and 7.94 km/s in the western margin of the Yangtze block, than in active or mobile tectonic units, such as 7.81 km/s in the Baoshan block, 7.72 km/s in the Tengchong block and 7.82 km/s in the Zhongdian block. (2) The crustal nature of the Tengchong block, the northern Lanping‐Simao block and the Zhongdian block reflects a type of orogenic belt, having relatively strong tectonic activities, whereas the crustal nature of the central Lanping‐Simao block and the western margin of the Yangtze block represents a type of platform. The different features of the upper‐middle crust velocity, Moho depth and Pn wave velocity to both sides of the Red River fault zone and the Xianshuihe fault zone, reflect that they are clearly ultra‐crustal. (3) Based on the distribution of the low velocity zones in the crust, the crustal material of the Tibetan Plateau is flowing in a NW–SE direction to the north of 26°N and to the west of 101°E, then diverting to flowing eastwards to the east of 101°E. [ABSTRACT FROM AUTHOR]

Inflammatory response plays an important role in ischaemia reperfusion injury (IRI) through a variety of inflammatory cells. Apart from neutrophils, macrophages and lymphocytes, the role of dendritic cells (DCs) in IRI has been noticed. The study was aimed at investigating whether the high‐mobility group protein box‐1/toll like receptor 4 (HMGB1/TLR4) signalling pathway regulate the migration, adhesion and aggregation of DCs to the myocardium, induce DCs activation and maturation, stimulate the expression of surface costimulatory molecules and participate in myocardial IRI. In vivo, migration, adhesion, and aggregation of DCs was enhanced; the expression of peripheral blood DCs CD80 and CD86, myocardial adhesion molecules were increased; and the infarct size was increased during myocardial ischaemia reperfusion injury myocardial ischemic/reperfusion injury (MI/RI). These responses induced by MI/RI were significantly inhibited by HMGB1 specific neutralizing antibody treatment. Cellular experiments confirmed that HMGB1 promoted the release of inflammatory cytokines through TLR4/MyD88/NF‐κB, upregulated CD80 and CD86 expression, mediated the damage of cardiomyocytes and accelerated the apoptosis. Our results indicate that DCs activation and maturation, stimulate the expression of surface costimulatory molecules by promoting the release of inflammatory factors through NF‐κB pathway and participate in myocardial IRI. [ABSTRACT FROM AUTHOR]

Software-defined networking simplifies network management by decoupling the control plane from the data plane and centralizing it to the controller. As the brain of the network, the controller gains up-to-date holistic network visibility via topology discovery. However, as a key service of topology discovery, the link discovery service opens problems on efficiency and security. On the one hand, sending link discovery packets to all ports wastes not only the limited controller resources (such as CPU and memory) but also control channel bandwidth. On the other hand, attackers may use these packets to create fake links and perform link fabrication attack. Because of the centralized control paradigm, wasting controller resources may degrade network performance, and all the fake links may severely poison the network topology, even causing the denial of service or man-in-the-middle attack. In this paper, we propose an efficient and secure link discovery scheme to improve link discovery performance and resist link fabrication attack caused by the software-defined networking link discovery service. By adopting port classification technique and directionally transmitting packets to appropriate ports, our approach can reduce or eliminate redundant packets and improve link discovery performance. Meanwhile, we adopt the directional packet transmitting approach and the time-marked hash-based message authentication code authenticate scheme to resist the link fabrication attack. A prototype system is implemented on the basis of POX controller and Mininet simulator to evaluate our scheme. Simulation results demonstrate that our scheme can solve the link fabrication problems with less overload of both the control plane and the data plane. [ABSTRACT FROM AUTHOR]

Software-defined networking that separates the control plane from the data plane is envisioned as a promising technology to enable resilient and flexible network management. Tolerating link failures is a fundamental problem in enhancing such network resilience in software-defined networking. Reactive and proactive fault tolerant schemes for conventional networks may not well balance the fault recovery time and network performance, since the proactive scheme typically underutilizes resources and the reactive scheme usually incurs a longer recovery time. In this paper, we propose a cooperative link failure recovery scheme to find a fine-grained trade-off between resource utilization and recovery time by combining reactive and proactive methods. We formalize the problem of link failure recovery as a multiobjective optimization problem and devise a 2-stage algorithm for it. The first stage of the algorithm guarantees connectivity restoration in an acceptable recovery interval based on fast failover feature supported in OpenFlow protocol, meanwhile it assigns virtual local area network tags to back up paths for achieving a lower memory consumption. The second stage of the algorithm guarantees the quality of service for different applications by adjusting the backup paths after rapid connectivity restoration. Extensive simulations highlight that cooperative link failure recovery scheme can satisfy both the carrier-grade recovery requirements and quality of service requirements in terms of delay and network bandwidth. [ABSTRACT FROM AUTHOR]

Summary: Software‐defined networking (SDN) emerges as the next generation of networking architecture, aiming to improve the network manageability and adaptability. However, because of the centralized control policy, SDN is liable to suffering from the denial of service attack in both the data plane and the control plane. To resist the attack and prevent the network from being paralyzed, we propose a novel mitigation scheme named flow migration defense, which uses a slave controller as a substitution to endure flooding requests mitigated from the master controller. Considering the special case that the normal requests may be regarded as the malicious ones, these requests are reforwarded back to the master controller on the basis of the round‐robin scheduling. To prevent the master controller from being flooded by the reforwarded requests, we design the adaptive rate adjustment method to adjust the reforwarding rate. Compared with multilevel feedback queue and FloodDefender, simulations demonstrate that flow migration defense can mitigate the SDN‐aimed denial of service attack efficiently with a better performance in terms of request response time, packet loss rate, and mitigation time. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) have many micro devices that are easy to capture. In node capture attacks, the adversary physically captures sensors and extracts all information including key information from their memories, trying to compromise the system's security protection. However, the robust and random nature of many WSN security designs makes it difficult to compromise the system even with the capture of some sensors. In this paper, we approach WSN security from an adversarial point of view and investigate low-cost and efficient algorithms to identify sensors in a WSN in the shortest time with the lowest cost. Instead of randomly capturing sensors, an intelligent attacker should choose the next target based on the known topology so far. Because the identification of such has been proven to be NP-hard (non-deterministic polynomial-time hard), we propose to transform the problem into a set covering problem and develop a greedy minimum cost node capture attack algorithm (MCA) to lower cost of attack. Extensive simulations have been implemented to evaluate the performance of MCA and to compare it with several related schemes. It is shown that MCA lowers the cost of compromising WSNs by 16%. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Pseudouridine (Ψ) is the most abundant internal modification identified in RNA, and yet little is understood of its effects on downstream reactions. Yeast U2 sn RNA contains three conserved Ψs (Ψ35, Ψ42, and Ψ44) in the branch site recognition region ( BSRR), which base pairs with the pre- mRNA branch site during splicing. Here, we show that blocks to pseudouridylation at these positions reduce the efficiency of pre- mRNA splicing, leading to growth-deficient phenotypes. Restoration of pseudouridylation at these positions using designer sno RNAs results in near complete rescue of splicing and cell growth. These Ψs interact genetically with Prp5, an RNA-dependent ATPase involved in monitoring the U2 BSRR-branch site base-pairing interaction. Biochemical analysis indicates that Prp5 has reduced affinity for U2 sn RNA that lacks Ψ42 and Ψ44 and that Prp5 ATPase activity is reduced when stimulated by U2 lacking Ψ42 or Ψ44 relative to wild type, resulting in inefficient spliceosome assembly. Furthermore, in vivo DMS probing analysis reveals that pseudouridylated U2, compared to U2 lacking Ψ42 and Ψ44, adopts a slightly different structure in the branch site recognition region. Taken together, our results indicate that the Ψs in U2 sn RNA contribute to pre- mRNA splicing by directly altering the binding/ ATPase activity of Prp5. [ABSTRACT FROM AUTHOR]

Advances in real-time system and wireless communication have led to the deployment of body area sensor networks (BASNs) for effective real-time healthcare applications. Real-time systems in BASNs tend increasingly to be probabilistic and mixed critical to meet stringent requirements on space, weight, and power consumption. Response-time analysis is an important and challenging task for BASNs to provide some critical services. In this paper, we propose a request-based compositional probabilistic response-time analysis framework for probabilistic real-time task models with fixed-priority preemptive scheduling in BASNs. In this method, each probabilistic real-time task is abstracted as a probabilistic request function. Rough response-time distribution is computed first based on the cumulative request distribution and then exact response-time distribution is obtained by refinement based on the request increase distribution. Our strategy can effectively improve performance by reducing repetitive computational overhead for the probabilistic response-time analysis of all tasks in the system. Our evaluation demonstrates that our proposed method significantly outperforms the existing probabilistic response-time analysis algorithm in terms of analysis duration. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) are expected to be widely deployed to collect data in military and civilian applications. Because of the open nature of WSNs, it is easy for an adversary to eavesdrop sensor communication and to trace packets, causing privacy concern for the sensor devices. The privacy issue, especially location privacy, can be critical for monitoring applications in WSNs. A unique case of location privacy is that of the sources, which are vulnerable of being captured and target attacks. In this paper, we propose a scheme to protect the source-location privacy based on a novel use of multiring topology. To achieve a uniformly distributed traffic pattern throughout the network, the source node selects two random rings each from its external rings and internal rings and a set of two random angles with a sum of 180 degrees for each packet. The packet is sent at one of the angles in each ring. Fake packets are also injected to provide path diversity and to increase attack time, which is defined as the time that the adversary takes to locate the source successfully. These techniques protect the source node from packet tracing attacks as well as traffic analysis attacks. Our analysis and simulations, performed in the NS2 simulator and MATLAB, demonstrate that our proposed scheme can provide better spatial traffic evenness and longer attack time, along with a modest increase of hop count and energy consumption.Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, a combined clustering algorithm namely enhanced clustering cloak (ECC), for protecting location privacy and query privacy is proposed. An iterative K-means clustering method is developed to group the user requests into clusters for providing location safety. Meanwhile, a hierarchical clustering method for preserving the query privacy is used when creating clusters. ECC provides users with desirable spatial and temporal tolerances. It can defend sampling attacks, homogeneity attacks, and query association attacks simultaneously. Simulation results present that the ECC algorithm not only has merits in smaller number of clusters, shorter cloaking time, higher entropy and QoS level but also preserves location privacy and query privacy in continuous location based services. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction There is an increasing interest in the patterns of mental health care of people with serious mental illnesses in China, where outpatient and community-based care are not fully developed and long-term hospitalization is still not uncommon. Comparison of sociodemographic and clinical characteristics of long-term and short-term inpatients diagnosed with schizophrenia can be informative about pattern of treatment and their relationship to services needs. Methods Seventy-three long-term schizophrenia inpatients (current length of stay of more than 5 years) were compared to 116 short-term schizophrenia inpatients (current length of stay of 30 days or less) assessed with the Individual Background Questionnaire, the Positive and Negative Syndrome Scale ( PANSS) and the Social Support Rating Scale ( SSRS). Results There was no significant difference between the groups on the total PANSS symptom score but the short-term inpatients scored significantly higher than their long-term counterparts on the Positive Syndrome sub-scale and the SSRS and lower on the Negative Syndrome sub-scale. Discussion Differences in symptomatology and social functioning may be related to better medication adherence and more extended social isolation among long-term inpatients while the increased positive symptoms are likely to reflect more acute disease process in short-term inpatients, and possibly poorer medication adherence. These differences may be especially pronounced in developing countries like China in which community-based services need to be more fully developed to facilitate medication adherence and prevent relapse, and to support community adjustment of socially isolated patients who otherwise require hospitalization. [ABSTRACT FROM AUTHOR]

Aim There has been considerable interest in identifying and addressing the specific needs of early-episode patients diagnosed with schizophrenia in the hope that by addressing such needs early, chronic disabilities can be avoided. Methods One hundred twenty-eight early-episode and 571 chronic patients were compared on socio-demographic characteristics, clinical symptoms and history of childhood trauma. Symptoms were measured with the Positive and Negative Syndrome Scale ( PANSS), and trauma with the short version of the Childhood Trauma Questionnaire. Results First-episode patients scored 9.3% higher than chronic patients on the PANSS positive symptom scale and 16.3% lower on the negative symptom scale. More first episode patients reported childhood sexual abuse ( P = 0.033); however, fewer reported childhood emotional neglect ( P = 0.01). Childhood trauma was associated with positive symptoms, specifically with hallucinations in first-episode patients ( r = 0.174; P = 0.049). Moreover, fewer parents of first episode patients were living alone ( P = 0.008). On multiple logistic regression, the first-episode patients were younger (odds ratio = 0.92), had higher PANSS positive symptom scores (odds ratio 1.04) and lower negative symptom scores (odds ratio 0.948 recalculate). Conclusions More positive symptoms, fewer negative symptoms, less isolated parents and greater risk of childhood sexual abuse might warrant attention in first episode schizophrenia and perhaps should be a focus for the development of targeted interventions. [ABSTRACT FROM AUTHOR]

All pseudouridines identified in RNA are considered constitutive modifications. Here, we demonstrate that pseudouridylation of Saccharomyces cerevisiae U2 snRNA can be conditionally induced. While only Ψ35, Ψ42 and Ψ44 are detected in U2 under normal conditions, nutrient deprivation leads to additional pseudouridylation at positions 56 and 93. Pseudouridylation at position 56 can also be induced by heat shock. Detailed analyses have shown that Pus7p, a single polypeptide pseudouridylase known to modify U2 at position 35 and tRNA at position 13, catalyses Ψ56 formation, and that snR81 RNP, a box H/ACA RNP known to modify U2 snRNA at position 42 and 25S rRNA at position 1051, catalyses Ψ93 formation. Using mutagenesis, we have demonstrated that the inducibility can be attributed to the imperfect substrate sequences. By introducing Ψ93 into log-phase cells, we further show that Ψ93 has a role in pre-mRNA splicing. Our results thus demonstrate for the first time that pseudouridylation of RNA can be induced at sites of imperfect sequences, and that Pus7p and snR81 RNP can catalyse both constitutive and inducible pseudouridylation. [ABSTRACT FROM AUTHOR]

Summary: As software‐defined networking (SDN) is a logically centralized technology, the control plane scalability in SDN is increasingly important with the network scale increasing. Load balancing and maximizing resource utilization are very critical to the control plane in SDN, while switch migration is an effective approach to achieve these two performance metrics. However, switch migration is NP‐hard problem because it belongs to the problem of combinatorial optimization. To avoid the NP‐hard problem, we propose a switch migration scheme by adopting noncooperative game to improve the control plane scalability in SDN. First, we design a novel load balancing monitoring scheme to detect the load imbalance between controllers and trigger migrating switches. Then, we use noncooperative game among controllers to decide switch migration to get the maximizing overall profits. Last, we prove that our proposed approach can get Pareto optimality. Extensive simulations prove that our method is able to achieve a more scalable control plane with load balancing and maximizing resource utilization. [ABSTRACT FROM AUTHOR]

Background The study was conducted to investigate clinical and computed tomography ( CT) features in Chinese lung cancer patients with human immunodeficiency virus ( HIV). Methods Forty consecutive lung cancer patients with HIV were included. Clinical data were collected, and CT features were reviewed and measured. The factors associated with stages of cancer and the CT features with opportunistic pulmonary infections ( OPIs) were also analyzed. Results Thirty-four of the patients were men (85%), and the mean age was 57.5 years. The mean CD4 count was 288 cells/μL, and 23 patients received highly active antiretroviral therapy. OPIs were common (50%). The major histological type (85%) was non-small cell lung cancer ( NSCLC), and 15 NSCLC patients (44%) were in stages IIIb and IV. NSCLC patients with an OPI were more common in the advanced stages compared with those without an OPI ( P = 0.04). There were no significant differences in advanced and non-advanced stages in terms of CD4 level, highly active antiretroviral therapy, and smoking ( P = 0.31, P = 1.00; P = 0.49, respectively). The average size of tumors was 4.5 cm. Irregularly shaped or larger sized tumors were associated with OPIs ( P = 0.03, P = 0.04, respectively). Conclusions The persistence of locally irregular and large lesions in middle-aged men with HIV and a history of OPIs should be an alert for lung cancer, and clinical management is needed. [ABSTRACT FROM AUTHOR]