Journal articles: 'Relais cellule'

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Giraudon, Pascale, Christophe Malcus, Aurélie Chalon, Peggy Vincent, Seng Khuth, Arlette Bernard, and Marie-Françoise Belin. "Les astrocytes, cellules relais des interactions neuro-immunes dans le système nerveux central." Journal de la Société de Biologie 197, no. 2 (2003): 103–12. http://dx.doi.org/10.1051/jbio/2003197020103.

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Viswanathan, H., and S. Mukherjee. "Performance of cellular networks with relays and centralized scheduling." IEEE Transactions on Wireless Communications 4, no. 5 (September 2005): 2318–28. http://dx.doi.org/10.1109/twc.2005.853820.

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Park, Won-Hyoung, and Saewoong Bahk. "Resource management policies for fixed relays in cellular networks." Computer Communications 32, no. 4 (March 2009): 703–11. http://dx.doi.org/10.1016/j.comcom.2008.11.039.

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Hindia, Mhd Nour, Moubachir Madani Fadoul, Tharek Abdul Rahman, and Iraj Sadegh Amiri. "A Stochastic Geometry Approach to Full-Duplex MIMO Relay Network." Wireless Communications and Mobile Computing 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/8342156.

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Cellular networks are extensively modeled by placing the base stations on a grid, with relays and destinations being placed deterministically. These networks are idealized for not considering the interferences when evaluating the coverage/outage and capacity. Realistic models that can overcome such limitation are desirable. Specifically, in a cellular downlink environment, the full-duplex (FD) relaying and destination are prone to interferences from unintended sources and relays. However, this paper considered two-hop cellular network in which the mobile nodes aid the sources by relaying the signal to the dead zone. Further, we model the locations of the sources, relays, and destination nodes as a point process on the plane and analyze the performance of two different hops in the downlink. Then, we obtain the success probability and the ergodic capacity of the two-hop MIMO relay scheme, accounting for the interference from all other adjacent cells. We deploy stochastic geometry and point process theory to rigorously analyze the two-hop scheme with/without interference cancellation. These attained expressions are amenable to numerical evaluation and are corroborated by simulation results.

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Khan, Aroba, and Abbas Jamalipour. "Moving Relays in Heterogeneous Cellular Networks—A Coverage Performance Analysis." IEEE Transactions on Vehicular Technology 65, no. 8 (August 2016): 6128–35. http://dx.doi.org/10.1109/tvt.2015.2478775.

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Cho, Sungmin, Youngseok Oh, Heejung Yu, and Woongsup Lee. "A New Cellular Network Structure Deploying Shared Relays with Sectorization." Wireless Personal Communications 94, no. 4 (September 28, 2016): 2987–99. http://dx.doi.org/10.1007/s11277-016-3761-3.

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Casado, Fanny L. "The Aryl Hydrocarbon Receptor Relays Metabolic Signals to Promote Cellular Regeneration." Stem Cells International 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/4389802.

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While sensing the cell environment, the aryl hydrocarbon receptor (AHR) interacts with different pathways involved in cellular homeostasis. This review summarizes evidence suggesting that cellular regeneration in the context of aging and diseases can be modulated by AHR signaling on stem cells. New insights connect orphaned observations into AHR interactions with critical signaling pathways such as WNT to propose a role of this ligand-activated transcription factor in the modulation of cellular regeneration by altering pathways that nurture cellular expansion such as changes in the metabolic efficiency rather than by directly altering cell cycling, proliferation, or cell death. Targeting the AHR to promote regeneration might prove to be a useful strategy to avoid unbalanced disruptions of homeostasis that may promote disease and also provide biological rationale for potential regenerative medicine approaches.

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Sherman, S. M., and R. W. Guillery. "Functional organization of thalamocortical relays." Journal of Neurophysiology 76, no. 3 (September 1, 1996): 1367–95. http://dx.doi.org/10.1152/jn.1996.76.3.1367.

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The thalamus has long been seen as responsible for relaying information on the way to the cerebral cortex, but it has not been until the last decade or so that the functional nature of this relay has attracted significant attention. Whereas earlier views tended to relegate thalamic function to a simple, machine-like relay process, recent research, reviewed in this article, demonstrates complicated circuitry and a rich array of membrane properties underlying the thalamic relay. It is now clear that the thalamic relay does not have merely a trivial function. Suggestions that the thalamic circuits and cell properties only come into play during certain phases of sleep to effectively disconnect the relay are correct as far as they go, but they are incomplete, because they fail to take into account interesting and variable properties of the relay that, we argue, occur during normal waking behavior. Although the specific function of the circuits and cellular properties of the thalamic relay for waking behavior is far from clear, we offer two related hypotheses based on recent experimental evidence. One is that the thalamus is not used just to relay peripheral information from, for example, visual, auditory, or cerebellar inputs, but that some thalamic nuclei are arranged instead to relay information from one cortical area to another. The second is that the thalamus is not a simple, passive relay of information to cortex but instead is involved in many dynamic processes that significantly alter the nature of the information relayed to cortex.

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Radunovic, Boz˘idar, and Alexandre Proutiere. "On Downlink Capacity of Cellular Data Networks With WLAN/WPAN Relays." IEEE/ACM Transactions on Networking 21, no. 1 (February 2013): 286–96. http://dx.doi.org/10.1109/tnet.2012.2198072.

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Chen, Yangyang, Feng Yan, and Xavier Lagrange. "Performance analysis of cellular networks with mobile relays under different modes." Telecommunication Systems 66, no. 2 (February 2, 2017): 217–31. http://dx.doi.org/10.1007/s11235-017-0284-5.

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Wang, Weipeng, Jihong Zhao, and Hua Qu. "Outage Probability Analysis for Two-Way Amplify-and-Forward Mobile Relay Assisted Device-to-Device Communication in Rayleigh Fading Channel." Journal of Physics: Conference Series 2218, no. 1 (March 1, 2022): 012005. http://dx.doi.org/10.1088/1742-6596/2218/1/012005.

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Abstract Device-to-Device (D2D) communication underlaying cellular network is potential to enhance the spectral efficiency, reduce the energy consumption and improve individual quality-of-service (QoS) experience. But intra-cell orthogonality is impaired due to spectral reusing and severe co-channel interference could be imposed between cellular and D2D links. Besides, the direct links between local communicating pairs may be unfavorable and suffer an unsatisfied QoS experience since the randomness of channel condition. So, we are focused on analyzing the outage probability of D2D links assisted by two-way relays on Rayleigh fading channel. Specifically, we consider an amplify-and-forward relay protocol at relay due to their limited processing ability, and devise power control at both D2D transmitter and relay to maintain the QoS requirement of prioritized cellular links. The simulation results verify the correctness of the outage probability analyses for D2D links, and indicate the performance gain when relays are introduced to facilitate D2D links.

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Na, Yu-Jin, Won-Seok Lee, Min-Jae Paek, Hyoung-Kyu Song, Duckdong Hwang, and Young-Hwan You. "Adaptive Relay Selection Scheme by Using Compound Channel." Applied Sciences 10, no. 16 (August 13, 2020): 5614. http://dx.doi.org/10.3390/app10165614.

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As a cellular network of the fifth generation (5G) is commercialized, mobile devices and data throughput have rapidly increased. According to the spatial density for communication increases, the nodes of cell are overloaded. Therefore, the heterogeneous ultra dense network (UDN) is suggested. Furthermore, the techniques for selecting a relay have been proposed in the Heterogeneous Net (HetNet). The relays are needed to improve communication performance and mitigate overload of nodes. In this paper, an adaptive relay selection scheme is proposed to obtain the diversity gain from multiple relays. To enhance the reliability of communication, the proposed scheme suggests a new algorithm considering outage probability and diversity gain of compound channel. Furthermore, the selected relays use an antenna selection algorithm to improve the channel capacity. Simulation results show that the proposed scheme improves the bit error rate (BER) and the data throughput.

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Liu, Chaowen, Chunlong He, Xingquan Li, Lei Huang, and Ying Liu. "Energy-Efficient Device-to-Device Communication Overlaying Cellular Networks with Cluster Relays." Journal of Physics: Conference Series 1069 (August 2018): 012060. http://dx.doi.org/10.1088/1742-6596/1069/1/012060.

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14

Zhang, Zhiwei, Yunzhou Li, Kaizhi Huang, Shidong Zhou, and Jing Wang. "Energy efficiency analysis of cellular networks with cooperative relays via stochastic geometry." China Communications 12, no. 9 (2015): 112–21. http://dx.doi.org/10.1109/cc.2015.7275249.

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15

Lin, Yicheng, and Wei Yu. "Fair Scheduling and Resource Allocation for Wireless Cellular Network with Shared Relays." IEEE Journal on Selected Areas in Communications 30, no. 8 (September 2012): 1530–40. http://dx.doi.org/10.1109/jsac.2012.120920.

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Shiloh, Y. "ATM (ataxia telangiectasia mutated): expanding roles in the DNA damage response and cellular homeostasis." Biochemical Society Transactions 29, no. 6 (November 1, 2001): 661–66. http://dx.doi.org/10.1042/bst0290661.

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DNA damage is one of the most acute threats to cellular homeostasis and life. The cell responds to such damage by activating a vast array of responses, ranging from DNA repair to numerous signalling pathways, which temporarily slow down the cellular life cycle while the damage is being repaired. Sophisticated relays convey the DNA damage alarm to all these systems immediately after damage infliction. Such relays must be capable of sensing the damage and rapidly creating functional contact with many signalling networks. The ataxia telangiectasia mutated (ATM) protein is a prominent example of such a relay. It responds swiftly to a critical DNA damage – the double strand break (DSB) – by phosphorylating key proteins in numerous signalling pathways. Evidence is emerging, however, that the ATM protein might also be involved in other processes related to cellular homeostasis, which are not directly associated with the damage response. ATM is the protein product of the gene mutated in the multisystem disorder ataxia-telangiectasia (AT), which is characterized by neuronal degeneration, immunodeficiency, chromosomal instability and cancer predisposition. The AT phenotype and the functions of the ATM protein revealed to date demonstrate the exceptionally multifaceted nature of this protein.

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Tayyab, Muhammad, George P. Koudouridis, Xavier Gelabert, and Riku Jantti. "Uplink Reference Signals for Power-Efficient Handover in Cellular Networks With Mobile Relays." IEEE Access 9 (2021): 24446–61. http://dx.doi.org/10.1109/access.2021.3056945.

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18

Gozalvez, Javier, and Baldomero Coll-Perales. "Experimental evaluation of multihop cellular networks using mobile relays [Accepted From Open Call]." IEEE Communications Magazine 51, no. 7 (July 2013): 122–29. http://dx.doi.org/10.1109/mcom.2013.6553688.

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Khan, Benish Sharfeen, Sobia Jangsher, Hassaan Khaliq Qureshi, and Syed Hassan Ahmed. "Predicted mobility based profitable relay selection in cooperative cellular network with mobile relays." Physical Communication 37 (December 2019): 100808. http://dx.doi.org/10.1016/j.phycom.2019.100808.

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20

Jangsher, Sobia, Haojie Zhou, Victor O. K. Li, and Ka-Cheong Leung. "Joint Allocation of Resource Blocks, Power, and Energy-Harvesting Relays in Cellular Networks." IEEE Journal on Selected Areas in Communications 33, no. 3 (March 2015): 482–95. http://dx.doi.org/10.1109/jsac.2015.2391916.

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21

You, Lei, Ping Wu, Mei Song, Junde Song, and Yong Zhang. "Cross-layer optimisation for uplink transmission in OFDMA cellular networks with fixed relays." European Transactions on Telecommunications 22, no. 6 (June 15, 2011): 296–314. http://dx.doi.org/10.1002/ett.1480.

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Devar, S., K. S. Karthik, B. Ramamurthi, and R. D. Koilpillai. "Downlink Throughput Enhancement of a Cellular Network using Two-Hop User-Deployable Indoor Relays." IEEE Journal on Selected Areas in Communications 31, no. 8 (August 2013): 1607–17. http://dx.doi.org/10.1109/jsac.2013.130822.

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23

Shrestha Khwakhali, Ushik, Prapun Suksompong, and Steven Gordon. "Midpoint Relay Selection Using Social Trust and Battery Level to Enhance Throughput in Cooperative Device-to-Device Communications." Sensors 20, no. 21 (October 23, 2020): 6007. http://dx.doi.org/10.3390/s20216007.

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Device-to-device communications in underlay mode has emerged as a promising way to enhance spectrum efficiency in cellular networks. Recently, relay selection in D2D communications underlaying cellular networks is gaining more research interest. In this paper, we propose two relay selection schemes for D2D communications underlaying cellular networks, Midpoint Relay Selection using Social Trust and Battery Level (MRS-ST-BL) and Midpoint Relay Selection using Social Distance and Battery Level (MRS-SD-BL). These proposed schemes utilize battery power level information of devices together with social trust information of users in the network for relay selection. For performance evaluation, initially we show that the throughput of state-of-the-art schemes Hybrid Relay Selection (HRS) and our previously proposed schemes Midpoint Relay Selection using Social Trust (MRS-ST) and Midpoint Relay Selection Using Social Distance (MRS-SD) decrease, when relays have varying battery power. Then, we compare the performance of our proposed schemes against existing schemes including HRS, MRS-ST and MRS-SD. The performance comparison is done at various social trust scenarios and device densities. We show that our proposed schemes can significantly improve the throughput of D2D communications, particularly when relays have different battery power levels in weak social trust scenarios. Finally, we show that the performance of our proposed scheme MRS-ST-BL varies with the change in battery power threshold.

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XU, Yue, Li-Fong SEET, Brendon HANSON, and Wanjin HONG. "The Phox homology (PX) domain, a new player in phosphoinositide signalling." Biochemical Journal 360, no. 3 (December 10, 2001): 513–30. http://dx.doi.org/10.1042/bj3600513.

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Phosphoinositides are key regulators of diverse cellular processes. The pleckstrin homology (PH) domain mediates the action of PtdIns(3,4)P2, PtdIns(4,5)P2 and PtdIns(3,4,5)P3, while the FYVE domain relays the pulse of PtdIns3P. The recent establishment that the Phox homology (PX) domain interacts with PtdIns3P and other phosphoinositides suggests another mechanism by which phosphoinositides can regulate/integrate multiple cellular events via a spectrum of PX domain-containing proteins. Together with the recent discovery that the epsin N-terminal homologue (ENTH) domain interacts with PtdIns(4,5)P2, it is becoming clear that phosphoinositides regulate diverse cellular events through interactions with several distinct structural motifs present in many different proteins.

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Gui, Jinsong, Jianglin Liu, and Xinran Zhou. "An Efficient Radio Resource Allocation Scheme considering Terminal Mobility in Dense mmWave Cellular Networks." Wireless Communications and Mobile Computing 2022 (June 23, 2022): 1–20. http://dx.doi.org/10.1155/2022/9558031.

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In millimeter wave (mmWave) communication systems, beamforming-enabled directional transmission and network densification are commonly used to reduce high path loss and improve signal coverage quality. The combination of the two approaches will pose a challenge to radio resource allocation, which is especially true when terminals move frequently. The existing works presented some effective solutions for resource allocation in dense mmWave cellular networks, but they assumed that terminals move infrequently. So, these works cannot be directly applied to the dense mmWave cellular networks where terminals move frequently. In this paper, based on the results of the existing beamforming training (BFT) information-aided radio resource allocation algorithm, we propose a relay selection method to select a set of reasonable relays to take over the terminals whose performance deteriorates due to movement, which can ensure that each selected relay is as close as possible to the original performance of the corresponding moved terminal. Then, the resource allocation problem between the Device to Device (D2D) links from the selected relays to the corresponding moved terminals is formulated as a potential game model. By designing the utility function reasonably, the resource allocation results on the D2D links can converge to a Nash equilibrium solution. The simulation results show that the proposed scheme adapts to the scenario with frequent terminal movement, restrains the sharp performance decline caused by terminal movement, and outperforms the existing related algorithms in terms of average energy efficiency and throughput per link.

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Kutikov, Artem B., Simon W. Moore, Richard T. Layer, Pamela E. Podell, Nithya Sridhar, Andrea J. Santamaria, Alex A. Aimetti, Christoph P. Hofstetter, Thomas R. Ulich, and James D. Guest. "Method and Apparatus for the Automated Delivery of Continuous Neural Stem Cell Trails Into the Spinal Cord of Small and Large Animals." Neurosurgery 85, no. 4 (August 29, 2018): 560–73. http://dx.doi.org/10.1093/neuros/nyy379.

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AbstractBackgroundImmature neurons can extend processes after transplantation in adult animals. Neuronal relays can form between injected neural stem cells (NSCs) and surviving neurons, possibly improving recovery after spinal cord injury (SCI). Cell delivery methods of single or multiple bolus injections of concentrated cell suspensions thus far tested in preclinical and clinical experiments are suboptimal for new tract formation. Nonuniform injectate dispersal is often seen due to gravitational cell settling and clumping. Multiple injections have additive risks of hemorrhage, parenchymal damage, and cellular reflux and require additional surgical exposure. The deposition of multiply delivered cells boluses may be uneven and discontinuous.ObjectiveTo develop an injection apparatus and methodology to deliver continuous cellular trails bridging spinal cord lesions.MethodsWe improved the uniformity of cellular trails by formulating NSCs in hyaluronic acid. The TrailmakerTM stereotaxic injection device was automatized to extend a shape memory needle from a single-entry point in the spinal cord longitudinal axis to “pioneer” a new trail space and then retract while depositing an hyaluronic acid-NSC suspension. We conducted testing in a collagen spinal models, and animal testing using human NSCs (hNSCs) in rats and minipigs.ResultsContinuous surviving trails of hNSCs within rat and minipig naive spinal cords were 12 and 40 mm in length. hNSC trails were delivered across semi-acute contusion injuries in rats. Transplanted hNSCs survived and were able to differentiate into neural lineage cells and astrocytes.CONCLUSIONThe TrailmakerTM creates longitudinal cellular trails spanning multiple levels from a single-entry point. This may enhance the ability of therapeutics to promote functional relays after SCI.

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Nguyen, Hong-Nhu, Nhat-Tien Nguyen, and Gia-Thinh Vo. "On performance analysis of non-orthogonal multiple access downlink for cellular-connected unmanned aerial vehicle relaying assisted vehicle-to-everything system." International Journal of Electrical and Computer Engineering (IJECE) 14, no. 2 (April 1, 2024): 1634. http://dx.doi.org/10.11591/ijece.v14i2.pp1634-1645.

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This paper presents the unmanned aerial vehicle (UAV) relays’ assisted vehicle-to-everything (V2X) network to implement the internet of things (IoT) systems with improvement in the coverage area. Such a network benefits from many advantages of the non-orthogonal multiple access (NOMA) scheme. We have implemented a decode-and-forward (DF) scheme for these UAVs. Then, we characterize the channels as Nakagami-m fading to evaluate the performance of the system. We derive closed-form expressions of outage probability (OP), ergodic capacity (EC), and throughput. The results show that the performance of the system depends on the transmitted signal-to-noise ratio (SNR) at the base station and the heights of the UAV relays. Target rate and power allocation factors are two main parameters that can be adjusted to achieve better performance. The results also compare to the system without UAV and OMA technique that shows the advantages of deploying UAV-assisted NOMA. Therefore, the design of NOMA for UAV relay-assisted V2X systems provides sufficient demand. The simulation results verified the effectiveness of the proposed UAV network and the precision of the theoretical analysis.

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Coll-Perales, B., and J. Gozalvez. "Contextual optimization of location-based routing protocols for multi-hop cellular networks using mobile relays." Telecommunication Systems 61, no. 4 (April 2, 2015): 793–805. http://dx.doi.org/10.1007/s11235-015-0036-3.

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Zarbouti, Dimitra, George Tsoulos, and Georgia Athanasiadou. "Effects of antenna array characteristics on in-band full-duplex relays for broadband cellular communications." ICT Express 1, no. 3 (December 2015): 121–26. http://dx.doi.org/10.1016/j.icte.2015.11.002.

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Aldonza, Mark Borris D., Jayoung Ku, Ji-Young Hong, Donghwa Kim, Seung Jung Yu, Min-Seok Lee, Monica Celine Prayogo, et al. "Prior acquired resistance to paclitaxel relays diverse EGFR-targeted therapy persistence mechanisms." Science Advances 6, no. 6 (February 2020): eaav7416. http://dx.doi.org/10.1126/sciadv.aav7416.

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Secondary drug resistance stems from dynamic clonal evolution during the development of a prior primary resistance. This collateral type of resistance is often a characteristic of cancer recurrence. Yet, mechanisms that drive this collateral resistance and their drug-specific trajectories are still poorly understood. Using resistance selection and small-scale pharmacological screens, we find that cancer cells with primary acquired resistance to the microtubule-stabilizing drug paclitaxel often develop tolerance to epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs), leading to formation of more stable resistant cell populations. We show that paclitaxel-resistant cancer cells follow distinct selection paths under EGFR-TKIs by enriching the stemness program, developing a highly glycolytic adaptive stress response, and rewiring an apoptosis control pathway. Collectively, our work demonstrates the alterations in cellular state stemming from paclitaxel failure that result in collateral resistance to EGFR-TKIs and points to new exploitable vulnerabilities during resistance evolution in the second-line treatment setting.

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Kang, Min Suk, Bang Chul Jung, and Dan Keun Sung. "Effect of cooperative and selection relaying schemes on multiuser diversity in downlink cellular systems with relays." Journal of Communications and Networks 10, no. 2 (June 2008): 175–85. http://dx.doi.org/10.1109/jcn.2008.6389837.

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Wu, Shuanshuan, Rachad Atat, Nicholas Mastronarde, and Lingjia Liu. "Improving the Coverage and Spectral Efficiency of Millimeter-Wave Cellular Networks Using Device-to-Device Relays." IEEE Transactions on Communications 66, no. 5 (May 2018): 2251–65. http://dx.doi.org/10.1109/tcomm.2017.2787990.

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Amponis, Georgios, Thomas Lagkas, Maria Zevgara, Georgios Katsikas, Thanos Xirofotos, Ioannis Moscholios, and Panagiotis Sarigiannidis. "Drones in B5G/6G Networks as Flying Base Stations." Drones 6, no. 2 (February 5, 2022): 39. http://dx.doi.org/10.3390/drones6020039.

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Advances in the fields of networking, broadband communications and demand for high-fidelity low-latency last-mile communications have rendered as-efficient-as-possible relaying methods more necessary than ever. This paper investigates the possibility of the utilization of cellular-enabled drones as aerial base stations in next-generation cellular networks. Flying ad hoc networks (FANETs) acting as clusters of deployable relays for the on-demand extension of broadband connectivity constitute a promising scenario in the domain of next-generation high-availability communications. Matters of mobility, handover efficiency, energy availability, optimal positioning and node localization as well as respective multi-objective optimizations are discussed in detail, with their core ideas defining the structure of the work at hand. This paper examines improvements to the existing cellular network core to support novel use-cases and lower the operation costs of diverse ad hoc deployments.

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WANG, Liping, Yusheng JI, and Fuqiang LIU. "Adaptive Subframe Partitioning and Efficient Packet Scheduling in OFDMA Cellular System with Fixed Decode-and-Forward Relays." IEICE Transactions on Communications E92.B, no. 3 (2009): 755–65. http://dx.doi.org/10.1587/transcom.e92.b.755.

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Hasan Al-Bowarab, Mustafa, Nurul Azma Zakaria, Zaheera Zainal Abidin, and Ziadoon Kamil Maseer. "Review on Device-to-Device Communication in Cellular based Network Systems." International Journal of Engineering & Technology 7, no. 3.20 (September 1, 2018): 435. http://dx.doi.org/10.14419/ijet.v7i3.20.20587.

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In a traditional cellular-network based system, the devices are not allowed to be interconnected directly in the certified mobile bandwidth, and all communications are carried out via the base station (BS). At present, device terminal broadcasting allows devices in the distributed network to act as transmitting relays to each other and reach a massive ad hoc network of networks that is different from the previous cellular architecture that faces technical challenges. Therefore, this article explores the application of a cellular-based two-layer network system that includes a base station (BS) cellular layer, such as cellular-to-device communication and communication between devices. In the proposed two-tier cellular-based network system, user data is transmitted through other users' devices to implement the privacy protection that is lacking in prior communication between devices in cellular systems. To ensure a negligible impact on the performance of current communication between devices, a two-layer network is assimilated to autonomous interference management schemes and associated resource allocation schemes. The findings from this review provide an overview of the major challenges in two-tier networks and propose a two-tier cellular-based system in which user data is routed through other users' devices to implement privacy protection.

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Park, Sang-Wook, Wei Li, Andrea Viehhauser, Bin He, Soonok Kim, Anders K. Nilsson, Mats X. Andersson, et al. "Cyclophilin 20-3 relays a 12-oxo-phytodienoic acid signal during stress responsive regulation of cellular redox homeostasis." Proceedings of the National Academy of Sciences 110, no. 23 (May 13, 2013): 9559–64. http://dx.doi.org/10.1073/pnas.1218872110.

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He, Chun, Haixia Cui, and Gang Feng. "Efficient Resource Scheduling by Exploiting Relay Cache for Cellular Networks." Mathematical Problems in Engineering 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/140727.

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In relay-enhanced cellular systems, throughput of User Equipment (UE) is constrained by the bottleneck of the two-hop link, backhaul link (or the first hop link), and access link (the second hop link). To maximize the throughput, resource allocation should be coordinated between these two hops. A common resource scheduling algorithm, Adaptive Distributed Proportional Fair, only ensures that the throughput of the first hop is greater than or equal to that of the second hop. But it cannot guarantee a good balance of the throughput and fairness between the two hops. In this paper, we propose a Two-Hop Balanced Distributed Scheduling (TBS) algorithm by exploiting relay cache for non-real-time data traffic. The evolved Node Basestation (eNB) adaptively adjusts the number of Resource Blocks (RBs) allocated to the backhaul link and direct links based on the cache information of relays. Each relay allocates RBs for relay UEs based on the size of the relay UE’s Transport Block. We also design a relay UE’s ACK feedback mechanism to update the data at relay cache. Simulation results show that the proposed TBS can effectively improve resource utilization and achieve a good trade-off between system throughput and fairness by balancing the throughput of backhaul and access link.

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Fadoul, Moubachir Madani. "Modeling multi-tier heterogeneous small cell networks: rate and coverage performance." Telecommunication Systems 75, no. 4 (July 7, 2020): 369–82. http://dx.doi.org/10.1007/s11235-020-00680-y.

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Abstract The rapid growth of small cells is driving cellular network toward randomness and heterogeneity. The multi-tier heterogeneous network (HetNet) addresses the massive connectivity demands of the emerging cellular networks. Cellular networks are usually modeled by placing each tier (e.g macro, pico and relay nodes) deterministically on a grid which ignores the spatial randomness of the nodes. Several works were idealized for not capturing the interference which is a major performance bottleneck. Overcoming such limitation by realistic models is much appreciated. Multi-tier relay cellular network is studied in this paper, In particular, we consider $${\mathscr {K}}$$ K -tier transmission modeled by factorial moment and stochastic geometry and compare it with a single-tier, traditional grid model and multi-antenna ultra-dense network (UDN) model to obtain tractable rate coverage and coverage probability. The locations of the relays, base stations, and users nodes are modeled as a Poisson Point Process. The results showed that the proposed model outperforms the traditional multi-antenna UDN model and its accuracy is confirmed to be similar to the traditional grid model. The obtained results from the proposed and comparable models demonstrate the effectiveness and analytical tractability to study the HetNet performance.

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Shan, Shu-ou. "Role of Hsp70 in Post-Translational Protein Targeting: Tail-Anchored Membrane Proteins and Beyond." International Journal of Molecular Sciences 24, no. 2 (January 6, 2023): 1170. http://dx.doi.org/10.3390/ijms24021170.

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The Hsp70 family of molecular chaperones acts as a central ‘hub’ in the cell that interacts with numerous newly synthesized proteins to assist in their biogenesis. Apart from its central and well-established role in facilitating protein folding, Hsp70s also act as key decision points in the cellular chaperone network that direct client proteins to distinct biogenesis and quality control pathways. In this paper, we review accumulating data that illustrate a new branch in the Hsp70 network: the post-translational targeting of nascent membrane and organellar proteins to diverse cellular organelles. Work in multiple pathways suggests that Hsp70, via its ability to interact with components of protein targeting and translocation machineries, can initiate elaborate substrate relays in a sophisticated cascade of chaperones, cochaperones, and receptor proteins, and thus provide a mechanism to safeguard and deliver nascent membrane proteins to the correct cellular membrane. We discuss the mechanistic principles gleaned from better-studied Hsp70-dependent targeting pathways and outline the observations and outstanding questions in less well-studied systems.

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Fournier, Henri-Noël, Sandra Dupé-Manet, Daniel Bouvard, Frédéric Luton, Simona Degani, Marc R. Block, Saverio Francesco Retta, and Corinne Albiges-Rizo. "Nuclear Translocation of Integrin Cytoplasmic Domain-associated Protein 1 Stimulates Cellular Proliferation." Molecular Biology of the Cell 16, no. 4 (April 2005): 1859–71. http://dx.doi.org/10.1091/mbc.e04-08-0744.

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Integrin cytoplasmic domain-associated protein 1 (ICAP-1) has been shown to interact specifically with the β1 integrin cytoplasmic domain and to control cell spreading on fibronectin. Interestingly, ICAP-1 also is observed in the nucleus, by immunocytochemical staining, and after biochemical cell fractionation, suggesting that it has additional roles that have yet to be determined. We show that the nucleocytoplasmic shuttling capability of ICAP-1 is dependent on a functional nuclear localization signal. In addition, overexpression of β1 integrin strongly reduced this nuclear localization, suggesting that integrin activity could modulate ICAP-1 shuttling by sequestering it in the cytoplasm. Indeed, the nuclear localization of ICAP-1 is dependent on the stage of cell spreading on fibronectin, and we also show that ICAP-1 expression stimulates cellular proliferation in a fibronectin-dependent manner. This function is dependent on its nuclear localization. Moreover, ICAP-1 is able to activate the c-myc promoter in vitro. Together, these results demonstrate that ICAP-1 shuttles between the nucleus and cytoplasm in a β1 integrin-dependent manner. It could act as a messenger that relays information from sites of integrin-dependent cell adhesion to the nucleus for controlling gene expression and cell proliferation.

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Gui, Jinsong, Lihuan Hui, and Naixue Xiong. "Enhancing Cellular Coverage Quality by Virtual Access Point and Wireless Power Transfer." Wireless Communications and Mobile Computing 2018 (2018): 1–19. http://dx.doi.org/10.1155/2018/9218239.

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The ultradensification deploying for cellular networks is a direct and effective method for the improvement of network capacity. However, the benefit is achieved at the cost of network infrastructure investment and operating overheads, especially when there is big gap between peak-hour Internet traffic and average one. Therefore, we put forward the concept of virtual cellular coverage area, where wireless terminals with high-end configuration are motivated to enhance cellular coverage quality by both providing RF energy compensation and rewarding free traffic access to Internet. This problem is formulated as the Stackelberg game based on three-party circular decision, where a Macro BS (MBS) acts as the leader to offer a charging power to Energy Transferring Relays (ETRs), and the ETRs and their associating Virtual Access Points (VAPs) act as the followers to make their decisions, respectively. According to the feedback from the followers, the leader may readjust its strategy. The circular decision is repeated until the powers converge. Also, the better response algorithm for each game player is proposed to iteratively achieve the Stackelberg-Nash Equilibrium (SNE). Theoretical analysis proves the convergence of the proposed game scheme, and simulation results demonstrate its effectiveness.

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Hassan, Hammad, Irfan Ahmed, Rizwan Ahmad, Hedi Khammari, Ghulam Bhatti, Waqas Ahmed, and Muhammad Mahtab Alam. "A Machine Learning Approach to Achieving Energy Efficiency in Relay-Assisted LTE-A Downlink System." Sensors 19, no. 16 (August 8, 2019): 3461. http://dx.doi.org/10.3390/s19163461.

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In recent years, Energy Efficiency (EE) has become a critical design metric for cellular systems. In order to achieve EE, a fine balance between throughput and fairness must also be ensured. To this end, in this paper we have presented various resource block (RB) allocation schemes in relay-assisted Long Term Evolution-Advanced (LTE-A) networks. Driven by equal power and Bisection-based Power Allocation (BOPA) algorithm, the Maximum Throughput (MT) and an alternating MT and proportional fairness (PF)-based SAMM (abbreviated with Authors’ names) RB allocation scheme is presented for a single relay. In the case of multiple relays, the dependency of RB and power allocation on relay deployment and users’ association is first addressed through a k-mean clustering approach. Secondly, to reduce the computational cost of RB and power allocation, a two-step neural network (NN) process (SAMM NN) is presented that uses SAMM-based unsupervised learning for RB allocation and BOPA-based supervised learning for power allocation. The results for all the schemes are compared in terms of EE and user throughput. For a single relay, SAMM BOPA offers the best EE, whereas SAMM equal power provides the best fairness. In the case of multiple relays, the results indicate SAMM NN achieves better EE compared to SAMM equal power and BOPA, and it also achieves better throughput fairness compared to MT equal power and MT BOPA.

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Billeke, Pablo, Tomas Ossandon, Marcela Perrone-Bertolotti, Philippe Kahane, Julien Bastin, Karim Jerbi, Jean-Philippe Lachaux, and Pablo Fuentealba. "Human Anterior Insula Encodes Performance Feedback and Relays Prediction Error to the Medial Prefrontal Cortex." Cerebral Cortex 30, no. 7 (February 28, 2020): 4011–25. http://dx.doi.org/10.1093/cercor/bhaa017.

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Abstract Adaptive behavior requires the comparison of outcome predictions with actual outcomes (e.g., performance feedback). This process of performance monitoring is computed by a distributed brain network comprising the medial prefrontal cortex (mPFC) and the anterior insular cortex (AIC). Despite being consistently co-activated during different tasks, the precise neuronal computations of each region and their interactions remain elusive. In order to assess the neural mechanism by which the AIC processes performance feedback, we recorded AIC electrophysiological activity in humans. We found that the AIC beta oscillations amplitude is modulated by the probability of performance feedback valence (positive or negative) given the context (task and condition difficulty). Furthermore, the valence of feedback was encoded by delta waves phase-modulating the power of beta oscillations. Finally, connectivity and causal analysis showed that beta oscillations relay feedback information signals to the mPFC. These results reveal that structured oscillatory activity in the anterior insula encodes performance feedback information, thus coordinating brain circuits related to reward-based learning.

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Lee, Keunwook, Prathyusha Gudapati, Mark Magnuson, Nigel Killeen, and Mark Boothby. "Mammalian target of rapamycin complex 2 regulates helper T cell differentiation and function (47.31)." Journal of Immunology 182, no. 1_Supplement (April 1, 2009): 47.31. http://dx.doi.org/10.4049/jimmunol.182.supp.47.31.

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Abstract Mammalian target of rapamycin (mTOR) is involved in cellular processes such as survival and proliferation. Regulation of the original rapamycin-sensitive complex, mTORC1, in signaling downstream from Akt is well defined. However, physiological roles in lymphoid cells of an alternative mTOR complex, mTORC2, are unknown. Using conditional deletion of rictor, an essential subunit of mTORC2, we recently uncovered a rate-limiting role of mTORC2 in T cell development and Akt activation. We now show that mTORC2 regulates helper T cell development and function by a pathway that is either Akt-dependent or largely independent of Akt, depending on the direction of differentiation. Specifically deleting rictor late in T cell ontogeny impaired T cell help to Ab class switching for both Th1- and Th2-regulated isotypes. mTORC2 relayed signaling of helper T cell help differentiation into both Th1 and Th2 effector cells, and proliferation distinct from pro-survival effects. Strikingly, a constitutive active Akt was sufficient to restore normal Th1, but not Th2 differentiation. Overall, our data indicate that mTORC2 plays fundamental roles in cellular differentiation while orchestrating differential signaling relays.

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Wheeler, Diek W., Paul H. M. Kullmann, and John P. Horn. "Estimating Use-Dependent Synaptic Gain in Autonomic Ganglia by Computational Simulation and Dynamic-Clamp Analysis." Journal of Neurophysiology 92, no. 5 (November 2004): 2659–71. http://dx.doi.org/10.1152/jn.00470.2004.

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Biological gain mechanisms regulate the sensitivity and dynamics of signaling pathways at the systemic, cellular, and molecular levels. In the sympathetic nervous system, gain in sensory-motor feedback loops is essential for homeostatic regulation of blood pressure and body temperature. This study shows how synaptic convergence and plasticity can interact to generate synaptic gain in autonomic ganglia and thereby enhance homeostatic control. Using a conductance-based computational model of an idealized sympathetic neuron, we simulated the postganglionic response to noisy patterns of presynaptic activity and found that a threefold amplification in postsynaptic spike output can arise in ganglia, depending on the number and strength of nicotinic synapses, the presynaptic firing rate, the extent of presynaptic facilitation, and the expression of muscarinic and peptidergic excitation. The simulations also showed that postsynaptic refractory periods serve to limit synaptic gain and alter postsynaptic spike timing. Synaptic gain was measured by stimulating dissociated bullfrog sympathetic neurons with 1–10 virtual synapses using a dynamic clamp. As in simulations, the threshold synaptic conductance for nicotinic excitation of firing was typically 10–15 nS, and synaptic gain increased with higher levels of nicotinic convergence. Unlike the model, gain in neurons sometimes declined during stimulation. This postsynaptic effect was partially blocked by 10 μM Cd2+, which inhibits voltage-dependent calcium currents. These results support a general model in which the circuit variations observed in parasympathetic and sympathetic ganglia, as well as other neural relays, can enable functional subsets of neurons to behave either as 1:1 relays, variable amplifiers, or switches.

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Zhang, Jinxi, Weidong Gao, Gang Chuai, and Zhixiong Zhou. "An Energy-Effective and QoS-Guaranteed Transmission Scheme in UAV-Assisted Heterogeneous Network." Drones 7, no. 2 (February 17, 2023): 141. http://dx.doi.org/10.3390/drones7020141.

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In this article, we consider a single unmanned aerial vehicle (UAV)-assisted heterogeneous network in a disaster area, which includes a UAV, ground cellular users, and ground sensor users. The cellular data and sensing data are transmitted to UAVs by cellular users and sensor users, due to the outage of the ground wireless network caused by the disaster. In this scenario, we aim to minimize the energy consumption of all the users, to extend their communication time and facilitate rescue. At the same time, cellular users and sensor users have different rate requirements, hence the quality of service (QoS) of the users should be guaranteed. To solve these challenges, we propose an energy-effective relay selection and resource-allocation algorithm. First, to solve the problem of insufficient coverage of the single UAV network, we propose to perform multi-hop transmission for the users outside the UAV’s coverage by selecting suitable relays in an energy-effective manner. Second, for the cellular users and sensor users inside the coverage of the UAV but with different QoS requirements, we design a non-orthogonal multiple access (NOMA)-based transmission scheme to improve spectrum efficiency. Deep reinforcement learning is exploited to dynamically adjust the power level and allocated sub-bands for inside users to reduce energy consumption and improve QoS satisfaction. The simulation results show that the proposed NOMA transmission scheme can achieve 9–17% and 15–32% performance gain on the reduction of transmit power and the improvement of QoS satisfaction, respectively, compared with state-of-the-art NOMA transmission schemes and orthogonal multiple access scheme.

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Azami, Farzin, Seyed Mostafa Safavi Hemami, and Abbas Akbarpour-Kasgari. "Joint Power Allocation and Beamforming in Amplify-and-Forward Relay Networks under Per-Node Power Constraint." Wireless Communications and Mobile Computing 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/5681236.

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Two-way relay networks (TWRN) have been intensively investigated over the past decade due to their ability to enhance the performance assessment of networks in terms of cellular coverage and spectral efficiency. Yet, power control in such systems is a nontrivial issue, particularly in multirelay networks where relays are deployed to ensure a required Quality of Service (QoS). In this paper, we envision to address this critical issue by minimizing the sum-power with respect to per-node power consumption and acceptable users’ rates. To tackle this, we employ a variable transformation to turn the fractional quadratically constrained quadratic problem (QCQP) into semidefinite programming (SDP). This algorithm is also extended to a distributed format. Simulation results of deploying 10 relay stations reveal that the total power consumption will decrease to approximately 8 dBW for 6 bps/Hz sum-rate.

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Holanda Viana, Thais Helena, Davi Arnaud, Fernanda Freire Collyer Correia, Vitoria Bezerra de Alencar, Velko Veras Pereira de Matos Filho, Vivian Romero Santiago, and Samyra Maria Vieira Brasil da Rocha. "FORENSIC GENETICS IN THE RESEARCH OF COLLECTIVE RAPE: CONCEPTUALIZATION AND CASE REPORT." Perspectivas em medicina legal e pericias medicas 7, no. 1 (December 1, 2022): e221225. http://dx.doi.org/10.47005/221225.

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Introduction: Sexual violence, within the scope of Legal Medicine, is exemplified by rape, mainly, whose epidemiology is devastating for female and black victims. The punishment of this crime is usually based on the analysis of materials containing DNA, found in forensic examinations. The aim of this study is to report a case of gang rape, explaining the importance and complexity of genetic profiling tests. Material and method: The present study is part of the case report modality, arising from a demand to clarify the nature of the suspects of a crime of gang rape. A narrative review of the literature on gang rape was also carried out in three open access databases. Results: GSL, a woman, a possible victim of gang rape, which occurred in the interior of Ceará, was submitted to an expert examination, in which samples of biological material were obtained, from her and from CAA, the main suspect, which were later analyzed by the Forensic Expert of the State of Ceara. Discussion: In the process of analyzing the samples, other cell types may be present, in addition to spermatozoa, such as epithelial cells. From such samples, DNA from non-sperm cells can be extracted. This strategy offers a great contribution in situations where a small amount of male material is found together with the victim’s cellular material. Conclusion: The possibility of CAA being the main suspect was compatible, but not the only one. Thus, the final result corroborated the main hypothesis of gang rape. Keywords: rape, genetic profiling, forensic genetics.

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Khan, Ajmal, Adnan Munir, Zeeshan Kaleem, Farman Ullah, Muhammad Bilal, Lewis Nkenyereye, Shahen Shah, Long D. Nguyen, S. M. Riazul Islam, and Kyung-Sup Kwak. "RDSP: Rapidly Deployable Wireless Ad Hoc System for Post-Disaster Management." Sensors 20, no. 2 (January 19, 2020): 548. http://dx.doi.org/10.3390/s20020548.

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In post-disaster scenarios, such as after floods, earthquakes, and in war zones, the cellular communication infrastructure may be destroyed or seriously disrupted. In such emergency scenarios, it becomes very important for first aid responders to communicate with other rescue teams in order to provide feedback to both the central office and the disaster survivors. To address this issue, rapidly deployable systems are required to re-establish connectivity and assist users and first responders in the region of incident. In this work, we describe the design, implementation, and evaluation of a rapidly deployable system for first response applications in post-disaster situations, named RDSP. The proposed system helps early rescue responders and victims by sharing their location information to remotely located servers by utilizing a novel routing scheme. This novel routing scheme consists of the Dynamic ID Assignment (DIA) algorithm and the Minimum Maximum Neighbor (MMN) algorithm. The DIA algorithm is used by relay devices to dynamically select their IDs on the basis of all the available IDs of networks. Whereas, the MMN algorithm is used by the client and relay devices to dynamically select their next neighbor relays for the transmission of messages. The RDSP contains three devices; the client device sends the victim’s location information to the server, the relay device relays information between client and server device, the server device receives messages from the client device to alert the rescue team. We deployed and evaluated our system in the outdoor environment of the university campus. The experimental results show that the RDSP system reduces the message delivery delay and improves the message delivery ratio with lower communication overhead.

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Gloerich, Martijn, Marjolein J. Vliem, Esther Prummel, Lars A. T. Meijer, Marije G. A. Rensen, Holger Rehmann, and Johannes L. Bos. "The nucleoporin RanBP2 tethers the cAMP effector Epac1 and inhibits its catalytic activity." Journal of Cell Biology 193, no. 6 (June 13, 2011): 1009–20. http://dx.doi.org/10.1083/jcb.201011126.

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Cyclic adenosine monophosphate (cAMP) is a second messenger that relays a wide range of hormone responses. In this paper, we demonstrate that the nuclear pore component RanBP2 acts as a negative regulator of cAMP signaling through Epac1, a cAMP-regulated guanine nucleotide exchange factor for Rap. We show that Epac1 directly interacts with the zinc fingers (ZNFs) of RanBP2, tethering Epac1 to the nuclear pore complex (NPC). RanBP2 inhibits the catalytic activity of Epac1 in vitro by binding to its catalytic CDC25 homology domain. Accordingly, cellular depletion of RanBP2 releases Epac1 from the NPC and enhances cAMP-induced Rap activation and cell adhesion. Epac1 also is released upon phosphorylation of the ZNFs of RanBP2, demonstrating that the interaction can be regulated by posttranslational modification. These results reveal a novel mechanism of Epac1 regulation and elucidate an unexpected link between the NPC and cAMP signaling.

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Journal articles on the topic 'Relais cellule'

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