Hematopoietic stem cell (HSC) maintenance depends on extrinsic cues. Currently, only local signals arising from the bone marrow niche have been shown to maintain HSCs. However, it is not known ...whether systemic factors also sustain HSCs. We assessed the physiological source of thrombopoietin (TPO), a key cytokine required for maintaining HSCs. Using
knock-in mice, we showed that TPO is expressed by hepatocytes but not by bone marrow cells. Deletion of
from hematopoietic cells, osteoblasts, or bone marrow mesenchymal stromal cells does not affect HSC number or function. However, when
is deleted from hepatocytes, bone marrow HSCs are depleted. Thus, a cross-organ factor, circulating TPO made in the liver by hepatocytes, is required for bone marrow HSC maintenance. Our results demonstrate that systemic factors, in addition to the local niche, are a critical extrinsic component for HSC maintenance.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
Bone marrow fibrosis is a critical component of primary myelofibrosis (PMF). However, the origin of the myofibroblasts that drive fibrosis is unknown. Using genetic fate mapping we found that bone ...marrow leptin receptor (Lepr)-expressing mesenchymal stromal lineage cells expanded extensively and were the fibrogenic cells in PMF. These stromal cells downregulated the expression of key haematopoietic-stem-cell-supporting factors and upregulated genes associated with fibrosis and osteogenesis, indicating fibrogenic conversion. Administration of imatinib or conditional deletion of platelet-derived growth factor receptor a (Pdgfra) from Lepr
stromal cells suppressed their expansion and ameliorated bone marrow fibrosis. Conversely, activation of the PDGFRA pathway in bone marrow Lepr
cells led to expansion of these cells and extramedullary haematopoiesis, features of PMF. Our data identify Lepr
stromal lineage cells as the origin of myofibroblasts in PMF and suggest that targeting PDGFRA signalling could be an effective way to treat bone marrow fibrosis.
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IJS, NUK, SBMB, UL, UM, UPUK
To understand the degradation and environmental fate of pyrethroids, the process of their photodegradation under simulated natural conditions was investigated. The results showed that the degradation ...process follows first-order kinetics. The degradation intermediates were identified with gas chromatography-mass spectrometry. A plausible mechanism was discussed to explain the process. Several influences on degradation process were investigated and reported such as the effects of initial concentration of pyrethroids, total time of light irradiation, solvents, and light source, as well as the effect of a few substances that exist in the environment. This study could be a good reference for the degradation of pyrethroids in practical circumstances.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Fuzzy clustering and routing protocols have been proven to improve energy efficiency, extend network scalability, increase network throughput, balance network load as well as prolong network ...lifetime. However, rules defined manually according to field experts are impossible or impractical to achieve the optimal solution for a Fuzzy Inference System (FIS). Therefore, a Novel Fuzzy Clustering and Routing Protocol called NFCRP is proposed in this paper by using an improved Particle Swarm Optimization (PSO) algorithm to tune the fuzzy rules. Firstly, one FIS is used to complete clustering based on effective input parameters including residual energy, node degree deviation, and distance to centrality, thereby forming optimal clusters and minimizing the intra-cluster energy consumption. Secondly, the other FIS is adopted to perform routing with descriptors residual energy, distance to BS, and data load deviation, hence addressing the inter-cluster energy consumption. Finally, the rules of both FISs are tuned by an improved PSO algorithm whose parameters are updated by introducing chaotic mapping and adaptive inertia weight. Simulation experiments were conducted to verify the performance of NFCRP against LEACH, EFUCA, EEFUC, FBCR and FMSFLA. According to the results, the average network lifetime of NFCRP increased by 79.59%, 47.99%, 50.35%,15.66 and 13.04%, compared to LEACH, EEFUC, EFUCA, FBCR and FMSFLA. For the average standard deviation of CH's traffic load, NFCRP decreased it by 29.29% over EEFUC, 31.42% over EFUCA, and 25.28% over FMSFLA. For network throughput, NFCRP outperformed LEACH, EEFUC, EFUCA, FBCR and FMSFLA by 16.87%, 46.52%, 48.18%, 29.97 and 71.79%. In addition, NFCRP also reduced energy consumption by 53.95%, 23.76%, 38.72%, 15.71 and 27.18% as compared to LEACH, EEFUC, EFUCA, FBCR and FMSFLA, respectively.
In Web service clustering, the service function vector (SFV) directly determines the quality of service (QoS) clustering. To improve service clustering performance, a method is proposed in this paper ...by integrating label-enhanced functional semantics and service collaboration. It improves the SFV from three aspects: generation model, corpus, and structural auxiliary information. At the generation model level, a Sentence-BERT is constructed based on singular value decomposition (SVD), to alleviate the anisotropy problem of BERT in vectorizing service descriptions. For corpus, the semantic features of SFV are supplemented by extracting specific named entities from service descriptions. Meanwhile, the service collaboration graph is established according to the collaboration relationship among Web services, which is conducive to the variational graph auto-encoders (VGAE) to realize service collaboration feature aggregation and further improve the SFV. Experiments show that the improved model, corpus and structural auxiliary information effectively enhance the SFV clustering. The proposed Web service clustering method is superior to the state-of-the-art methods.
Abstract
Background and aims
Alcoholic fatty liver (AFL) is a liver disease caused by long-term excessive drinking and is characterized by hepatic steatosis. Understanding the regulatory mechanism of ...steatosis is essential for the treatment of AFL. Rev-erbα is a member of the Rev-erbs family of nuclear receptors, playing an important role in regulating lipid metabolism. However, its functional role in AFL and its underlying mechanism remains unclear.
Results
Rev-erbα was upregulated in the liver of EtOH-fed mice and EtOH-treated L-02 cells. Further, Rev-erbα activation exacerbates steatosis in L-02 cells. Inhibition/downexpression of Rev-erbα improved steatosis. Mechanistically, autophagy activity was inhibited in vivo and vitro. Interestingly, inhibition/downexpression of Rev-erbα enhanced autophagy. Furthermore, silencing of Rev-erbα up-regulated the nuclear expression of Bmal1. Autophagy activity was inhibited and steatosis was deteriorated after EtOH-treated L-02 cells were cotransfected with Rev-erbα shRNA and Bmal1 siRNA.
Conclusions
Rev-erbα induces liver steatosis, which promotes the progression of AFL. Our study reveals a novel steatosis regulatory mechanism in AFL and suggest that Rev-erbα might be a potential therapeutic target for AFL.
Solid oxide electrolysis cell (SOEC) is a promising technology for CO2 conversion and renewable energy storage with high efficiency. It is highly desirable to develop catalytically active cathodes ...for CO2 electrolysis. Herein, cathode materials with different structural stabilities are designed by Nb substitution on La0.5Sr0.5Fe0.8Co0.2O3-δ (LSFC82) to obtain La0.5Sr0.5Fe0.7Co0.2Nb0.1O3-δ (LSFCN721) and La0.5Sr0.5Fe0.8Co0.1Nb0.1O3-δ (LSFCN811), respectively. LSFC82-Sm0.2Ce0.8O2-δ (SDC) cathode with inferior structural stability (ability to maintain the structure) shows desirable CO2 electrolysis performance with the generated current density of 1.80 A cm−2 at 1.6 V and stable performance during 110 h operation at 1.2 V and 800 °C. However, LSFC82 particles are collapsed into pieces after stability test with the generation of Co nanoparticles simultaneously. The frameworks of LSFCN721 and LSFCN811 particles maintain well because of the high-valent niobium, but Co exsolution, oxygen vacancy content and the corresponding CO2 electrolysis performance are restricted. This work confirms that Co nanoparticles can be exsolved from LSFC82-SDC cathode during CO2 electrolysis, providing references for constructing metallic nanoparticles decorated-perovskite cathodes for SOECs.
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•CO2 electrolysis performance of LSFC-based SOEC cathodes was evaluated.•LSFC82-SDC cathode exhibited high CO2 electrolysis performance and stability.•Co nanoparticles were exsolved from LSFC82 during CO2 electrolysis.•LSFC82 particles were collapsed into pieces during SOEC operation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
During the liver fibrosis recovery stage tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can effectively induce apoptosis of activated hepatic stellate cells (HSCs). Normal hepatic ...stellate cells are resistant to TRAIL cytotoxicity. Therefore, enhancing the sensitivity of TRAIL-induced apoptosis of HSCs may be useful to treat hepatic fibrogenesis. Here, we demonstrated that miR-145 and TRAIL were down-regulated in both liver fibrosis tissue samples and transforming growth factor-β1 induced HSCs, concomitant with increased the expression of ZEB2. In addition, we found that mimics-mediated over-expression of miR-145 led to resistance to the ZEB2 expression and up-regulation of the TRAIL-induced apoptosis after treatment of LX-2 cells with TRAIL. Furthermore, ZEB2-siRNA transfected LX-2 cells showed the increased sensitivity to TRAIL-induced apoptosis. Whereas, opposite results were obtained in miR-145-inhibitor group or ZEB2 plasmid group. Moreover, miR-145 regulated ZEB2 gene expression by specifically interacting with the 3'-UTR of ZEB2 mRNA to inhibit the expression of ZEB2. Further studies showed that the over-expression of ZEB2 could inhibit TRAIL-induced apoptosis via inhibiting nuclear factor-κB (NF-κB) signaling pathway in LX-2 cells. Collectively, our data suggest that up-regulation of miR-145 can down-regulate ZEB2 expression, consequently promoting TRAIL-induced apoptosis in LX-2 cells through NF-κB signaling pathway, which facilitates the resolution of liver fibrosis.
A low-power grid-connected photovoltaic (PV) power generation system based on automatic solar tracking is designed in this paper. In order to increase the level of accuracy of automatic solar ...tracking, the part of automatic solar tracking adopts the method of hybrid tracking and uses pin-cushion two-dimensional position sensitive detector plus four silicon PV cells as the photosensitive element. An adaptive topological structure of the main circuit based on a cascaded Boost converter circuit and the H6-type inverter topology are designed for the system to obtain a better working condition. Then an MPPT algorithm combined modified constant voltage algorithm with modified variable step-size increment conductance algorithm is proposed in order to improve the efficiency of PV power generation. The experimental results showed the effectiveness of the control system. Finally, the hardware and software of the system are also designed. Moreover, a graphic interface made with the LabVIEW software allows the user to monitor and save the data in a file.
Multimodal optimization aims to find and maintain as many global and local optima of a function as possible. Niching techniques based on multi-populations and clustering proved to be efficient for ...tackling multimodal optimization problems. The main focus of this work is to enhance the diversity of the population and improve the global search ability to locate more optima. A Double-Layer-Clustering Speciation Differential Evolution (DLCSDE) algorithm for multimodal optimization is proposed. We also show how the DLCSDE can be improved by integrating with a self-adaptive strategy to form the Self-adaptive DLCSDE (SDLCSDE). Based on speciation, first layer clustering divides the entire population into multiple subpopulations to locate global and local optima. The seeds from each species then form a sub-population to search globally during the second layer clustering to find peaks missed during the first layer clustering search process. To test the performance, both DLCSDE and SDLCSDE are compared with 17 state-of-art niching algorithms on 29 multimodal problems with different dimensions. The experiment results demonstrate that both the proposed algorithms outperform or perform comparably to the 17 niching algorithms on all the test functions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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