Non-orthogonal multiple access (NOMA) is indeed an important technique of 5 G and beyond 5 G (B5G) communication systems, as it can increase the spectrum efficiency and system capacity under the same ...bandwidth. Long-distance unmanned aerial vehicle (UAV) networks, comprising a base station and multiple UAVs, are commonly used for reconnaissance purposes due to the extended flight range of the UAVs, which can provide broad coverage and satisfy the requirements for real-time communication. To alleviate spectrum underutilization of single channel orthogonal multiple access, we investigate resource allocation in UAV networks by utilizing NOMA and then formulate an optimization problem that maximizes the network capacity. The formulated problem can be decomposed into two sub-problems, namely UAV grouping and power allocation optimization. Accordingly, we present a UAV grouping method with low complexity according to the difference of channel gain between UAVs and base station, in which the UAVs with larger difference will be in the same cluster such that they can transmit signals over the same channel. Then, a power allocation optimization algorithm based on Lagrange multiplier method is then used to optimize the transmit power of UAVs utilizing the same channel. This algorithm considers the quality of service requirements for each UAV, and assigns power levels that maximize the overall network capacity. Simulation results have shown that the presented algorithms improve network capacity by approximately 19% compared with that of orthogonal multiple access, which demonstrates the effectiveness of utilizing NOMA in long-distance UAV networks.
Regulatory T cells (T
cells), which have abundant expression of the interleukin 2 receptor (IL-2R), are reliant on IL-2 produced by activated T cells. This feature indicates a key role for a simple ...network based on the consumption of IL-2 by T
cells in their suppressor function. However, congenital deficiency in IL-2R results in reduced expression of the T
cell lineage-specification factor Foxp3, which has confounded experimental efforts to understand the role of IL-2R expression and signaling in the suppressor function of T
cells. Using genetic gain- and loss-of-function approaches, we found that capture of IL-2 was dispensable for the control of CD4
T cells but was important for limiting the activation of CD8
T cells, and that IL-2R-dependent activation of the transcription factor STAT5 had an essential role in the suppressor function of T
cells separable from signaling via the T cell antigen receptor.
Abstract X-linked hyper-IgM syndrome (XHM) is a combined immune deficiency disorder caused by mutations in CD40 ligand. We tested CP-870,893, a human CD40 agonist monoclonal antibody, in the ...treatment of two XHM patients with biliary Cryptosporidiosis. CP-870,893 activated B cells and APCs in vitro, restoring class switch recombination in XHM B cells and inducing cytokine secretion by monocytes. CP-870,893 infusions were well tolerated and showed significant activity in vivo, decreasing leukocyte concentration in peripheral blood. Although specific antibody responses were lacking, frequent dosing in one subject primed T cells to secrete IFN-g and suppressed oocyst shedding in the stool. Nevertheless, relapse occurred after discontinuation of therapy. The CD40 receptor was rapidly internalized following binding with CP-870,893, potentially explaining the limited capacity of CP-870,893 to mediate immune reconstitution. This study demonstrates that CP-870,893 suppressed oocysts shedding in XHM patients with biliary cryptosporidiosis. The continued study of CD40 agonists in XHM is warranted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Intestinal microbes provide multicellular hosts with nutrients and confer resistance to infection. The delicate balance between pro- and anti-inflammatory mechanisms, essential for gut immune ...homeostasis, is affected by the composition of the commensal microbial community. Regulatory T cells (Treg cells) expressing transcription factor Foxp3 have a key role in limiting inflammatory responses in the intestine. Although specific members of the commensal microbial community have been found to potentiate the generation of anti-inflammatory Treg or pro-inflammatory T helper 17 (TH17) cells, the molecular cues driving this process remain elusive. Considering the vital metabolic function afforded by commensal microorganisms, we reasoned that their metabolic by-products are sensed by cells of the immune system and affect the balance between pro- and anti-inflammatory cells. We tested this hypothesis by exploring the effect of microbial metabolites on the generation of anti-inflammatory Treg cells. We found that in mice a short-chain fatty acid (SCFA), butyrate, produced by commensal microorganisms during starch fermentation, facilitated extrathymic generation of Treg cells. A boost in Treg-cell numbers after provision of butyrate was due to potentiation of extrathymic differentiation of Treg cells, as the observed phenomenon was dependent on intronic enhancer CNS1 (conserved non-coding sequence 1), essential for extrathymic but dispensable for thymic Treg-cell differentiation. In addition to butyrate, de novo Treg-cell generation in the periphery was potentiated by propionate, another SCFA of microbial origin capable of histone deacetylase (HDAC) inhibition, but not acetate, which lacks this HDAC-inhibitory activity. Our results suggest that bacterial metabolites mediate communication between the commensal microbiota and the immune system, affecting the balance between pro- and anti-inflammatory mechanisms.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In skeletal muscle and many other cell types, mitochondria exist as an elaborate and dynamic network in which "individual" mitochondria exist only transiently even under nonstimulated conditions. The ...balance of continuous mitochondrial fission and fusion defines the morphology of the mitochondrial reticulum. Environmental stimuli, such as oxidative stress, can influence fusion and fission rates, resulting in a transformation of the network's connectivity. Using confocal laser scanning microscopy of C(2)C(12) mouse myocytes, we show that acute exposure to the reactive oxygen species (ROS) hydrogen peroxide (H(2)O(2)) induces a slow fragmentation of the mitochondrial reticulum that is reversible over 24h. Although H(2)O(2) decomposes rapidly in culture medium, the full extent of fragmentation occurs 5-6h posttreatment, suggesting that H(2)O(2) affects mitochondrial morphology by modulating cellular physiology. Supraphysiological (>1 mM) concentrations of H(2)O(2) are cytotoxic, but lower concentrations (250 μM) sufficient to induce transient fragmentation do not lower cell viability. H(2)O(2)-induced mitochondrial fragmentation is preceded by decreases in inner mitochondrial membrane potential and maximal respiratory rate, suggesting a possible mechanism. Because H(2)O(2) is produced in contracting muscle, our results raise the possibility that ROS generation may contribute to exercise-induced changes in mitochondrial morphology in vivo.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In Vehicular Networks (VANETs), the rapid movement of vehicles leads to highly time-varying network topology and brings the problem of blind spots in signal coverage. To address these issues, drones ...are employed to assist data dissemination in VANETs attribute to the flexible development of drones. As random data transmission will result in decreased network performance and low efficiency in data retrieval service, it is urgent to develop efficient data scheduling schemes that meet the quality of service (QoS) of different applications in VANETs. In this context, to fulfill the request of real-time and reliable data transmission, we formulate a data scheduling problem that considers the factors such as priority of data transmission, link quality, link connection time and network fairness. Our goal is to reduce random data transmission, therefore maximizing network transmission utility. We utilize graph theory to describe network topology, in which vehicles and drones are represented as vertices and links between the nodes are represented as edges. The weight of edges indicates the utility obtained when data transmits between the corresponding nodes. We reduce the data scheduling problem to the maximum weighted matching problem and then propose a data scheduling scheme that can satisfy data requests of different vehicles to the maximum extent. The theoretical analysis derives the scheduling algorithm’s time complexity and the number of scheduling stages required to satisfy the data requests. Finally, simulation verifies the proposed scheme’s effectiveness in terms of service rate, service delay, fairness and throughput.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Software Defined Networking (SDN) has emerged as a new paradigm that offers the programmability required to dynamically configure and control a network. In this paper, we present a path assignment ...method based on load balancing(PA-LB) for a centralized controller to calculate optimal end-to-end virtual paths over the underlying network infrastructure, considering multiple requests and load balance simultaneously. In the paper, theoretical analysis shows that the path selection is NP-hard, and strongly polynomial time inapproximable under the assumption P not equal to NP. We also give a constant-factor polynomial time approximation algorithm for this problem under some bounded parameters. Extensive simulation results, over a wide range of underlying network topologies and input parameters, demonstrate that the proposed method outperforms traditional shortest path first (SPF) approaches not only in paths mapping number, but also in network load balance. Under the condition of limited resources, such as bandwidth, the proposed method has a better performance with the increase of the number of nodes. Moreover, optimal load balance can be kept in the network, in order to avoid network congestion and minimize the average packet transmission latency.
Innate lymphoid cells (ILCs) function to protect epithelial barriers against pathogens and maintain tissue homeostasis in both barrier and non-barrier tissues. Here, utilizing Eomes reporter mice, we ...identify a subset of adipose group 1 ILC (ILC1) and demonstrate a role for these cells in metabolic disease. Adipose ILC1s were dependent on the transcription factors Nfil3 and T-bet but phenotypically and functionally distinct from adipose mature natural killer (NK) and immature NK cells. Analysis of parabiotic mice revealed that adipose ILC1s maintained long-term tissue residency. Diet-induced obesity drove early production of interleukin (IL)-12 in adipose tissue depots and led to the selective proliferation and accumulation of adipose-resident ILC1s in a manner dependent on the IL-12 receptor and STAT4. ILC1-derived interferon-γ was necessary and sufficient to drive proinflammatory macrophage polarization to promote obesity-associated insulin resistance. Thus, adipose-resident ILC1s contribute to obesity-related pathology in response to dysregulated local proinflammatory cytokine production.
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•Adipose ILC1s represent a stable population distinct from immature and mature NK cells•Adipose ILC1s, but not mature NK cells, are tissue resident•Adipose ILC1 IFN-γ contributes to M1 macrophage polarization and insulin resistance•IL-12 and STAT4 drive proliferation and accumulation of adipose ILC1 during obesity
Here, Sun and colleagues demonstrate that adipose group 1 innate lymphoid cells (ILCs) contain distinct populations of immature and mature NK cells and tissue-resident ILC1. Adipose-resident ILC1s selectively accumulate in the adipose depots following diet-induced obesity and produce IFN-γ in response to IL-12 production to contribute toward M1 macrophage polarization and insulin resistance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The qualities of injection-molded parts are affected by process parameters. Warpage and volume shrinkage are two typical defects. Moreover, insufficient or excessively large clamping force also ...affects the quality of parts and the cost of the process. An experiment based on the orthogonal design was conducted to minimize the above defects. Moldflow software was used to simulate the injection process of each experiment. The entropy weight was used to determine the weight of each index, the comprehensive evaluation value was calculated, and multi-objective optimization was transformed into single-objective optimization. A regression model was established by the random forest (RF) algorithm. To further illustrate the reliability and accuracy of the model, back-propagation neural network and kriging models were taken as comparative algorithms. The results showed that the error of RF was the smallest and its performance was the best. Finally, genetic algorithm was used to search for the minimum of the regression model established by RF. The optimal parameters were found to improve the quality of plastic parts and reduce the energy consumption. The plastic parts manufactured by the optimal process parameters showed good quality and met the requirements of production.
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