This study analyzes the effect of urban network externalities on urban growth and compares it with that of agglomeration economies from the perspective of the externality theory. Traditional regional ...and urban economic theories emphasize the role of agglomeration economies in promoting regional growth. However, urban networks have gradually become the main form of regional economic systems. Urban network externalities are also becoming increasingly critical with the dramatic development of infrastructure and information technology. This study identifies the national urban network and analyzes its structure and characteristics using complex network methods based on the data of train frequency among 273 municipal districts in China. Then, an urban growth model is constructed with Spatial Durbin Model specifications to examine the impact of urban network externalities on economic growth and compare it with that of agglomeration economies. The results show that the urban network externality has a significant effect on promoting urban economic development; cities with higher in-closeness centrality tend to enjoy higher economic growth due to their central position in the network. Moreover, compared with agglomeration economies, urban network externalities do not depend on the geographical proximity of cities but on the connections in the network, and can generate cross-spatial spillover effects.
•Train frequency data of 273 municipal districts of prefecture-level Chinese cities.•Urban network externality has a positive effect on urban economic development.•Urban network externality depends on network connections rather than geographical proximity of cities.•Urban network externalities can generate cross-spatial spillover effects•Cities with higher in-closeness centrality tend to enjoy higher economic growth.
In the airborne or spaceborne radar applications, prolonging the coherent integration time is one of the effective methods to improve the radar detection ability of a weak maneuvering target, whereas ...the coherent integration performance may degrade due to the complex range migration (RM) and Doppler frequency migration (DFM) effects. In this paper, detection and motion parameter estimation for a weak maneuvering target with the third-order RM and DFM are considered. Firstly, Keystone transform is applied to compensate the linear range walk. Then, the matched filtering processing is performed in the range-frequency and azimuth-time domain to eliminate the residual coupling effects between range and azimuth. Finally, a well-focused image of a moving target is obtained, and three motion parameters, i.e., velocity, acceleration, and acceleration rate, are effectively estimated. In addition, as for a fast-moving target with Doppler ambiguity, two cases, i.e., target azimuth spectrum within a pulse repetition frequency (PRF) and spanning over neighboring PRF bands, are analyzed. Compared with the generalized Radon Fourier transform (GRFT), the proposed method can acquire a close integration performance but with lower computational complexity since the parameter searching dimension is reduced. Simulated processing results are provided to validate the effectiveness of the proposed method.
Rheumatoid arthritis (RA) is one of the chronic systemic autoimmune diseases that cardinally affect the joints. Many people all over the world suffer from the disease. Fibroblast‐like synoviocytes ...(FLSs) play a significant role in the occurrence and development of RA. The long noncoding RNA maternally expressed gene 3 (MEG3) is an imprinted gene, which participates in various cancers as a tumor suppressor. Previous studies have shown that nucleotide oligomerization domain (NOD)‐like receptors 5 (NLRC5) plays a key role in inflammatory and autoimmune diseases. Nonetheless, we know very little about the biofunctionality of MEG3 during the development of RA. In this paper, we used complete Freund's adjuvant (CFA)‐induced rats as RA animal models. The level of MEG3 significantly reduced in CFA‐induced synovial tissues and FLSs, whereas the NLRC5 levels were increased. Enforced expression of MEG3 may be responsible for the decreased level of NLRC5 and inflammatory cytokine level. The results of methylation‐specific PCR suggested that the MEG3 gene promoter was significantly methylated in CFA‐induced synovial tissues and FLSs. More important, hypermethylation of MEG3 promoter could be inhibited by 5‐aza‐2‐deoxycytidine (5‐azadC; methylation inhibitor). Besides, the expression of NLRC5 significantly decreased followed by 5‐azadc. Furthermore, DNA methyltransferases 1 (DNMT1) increased in CFA‐induced synovial tissues and cells. These results indicated that MEG3 regulates RA by targeting NLRC5 potentially.
Maternally expressed gene 3 (MEG3) may be involved in the development of rheumatoid arthritis (RA) by affecting the proliferation of fibroblast‐like synoviocytes (FLSs), whereas nucleotide oligomerization domain (NOD)‐like receptors 5 (NLRC5) promotes proliferation of FLSs in RA. Enforced expression of MEG3 decreased NLRC5 expression. These results further verified that MEG3 regulates RA by targeting NLRC5 potentially.
In recent years, the utilization of phase change materials (PCMs) in photovoltaic (PV) module for thermal regulation has attracted wide attention in this field, as the hybrid PV-PCM technology can ...not only achieve higher photoelectric conversion efficiency but also make it possible to extract thermal energy stored in PCMs for cascade utilization. Although substantial research has been carried out on PV-PCM systems, the promise of practical application is still far from clear with some barriers unsolved, such as PCMs which need further improvements in both technical and economical view. In this paper, a comprehensive literature review of the state-of-the-art aspects of PV-PCM systems is presented, with the focus on technology overview and materials selection. The concept of hybrid PV-PCM system is first discussed with its general configuration and energy balance, to figure out the key factors affecting its performance. Besides, the development route of PV-PCM research is outlined through a comprehensive review of 104 research articles during 2004–2018, clarifying the representative achievements and existing problems in each stage. Furthermore, PCMs are highlighted in this paper with details on their classification, properties, and application in previous PV-PCM research. In particular a triangle about materials selection criteria and determination strategy of phase transition temperature is proposed. Finally, the challenges and prospects of future research on PV-PCM systems are raised, advocating that more attention should be addressed on new strategies to overcome the existing problems such as insufficient reliability and economic feasibility.
•A comprehensive literature review of the state-of-the-art aspects of PV-PCM systems is presented.•A complete development route of PV-PCM technology at different research stages is outlined.•A triangle about materials selection criteria and determination strategy of phase transition temperature is proposed.•Challenges and perspectives for future research are raised.
We designed a new single-carrier-detection-based wake-up receiver (SCD WuR), which can noncoherently detect a single carrier in a wide bandwidth with a small number of samples. The closed-form ...expression of the detection error rate of the SCD WuR is derived and validated. The performance of SCD WuR is also evaluated in terms of the minimum detectable signal-to-noise ratio, the power, and the wake-up time.
This paper presents a detailed feasibility study and techno-economic evaluation of a standalone hybrid solar-wind system with battery energy storage for a remote island. The solar radiation and wind ...data on this island in 2009 was recorded for this study. The HOMER software was employed to do the simulations and perform the techno-economic evaluation. Thousands of cases have been carried out to achieve an optimal autonomous system configuration, in terms of system net present cost (NPC) and cost of energy (COE). A detailed analysis, description and expected performance of the proposed system were presented. Moreover, the effects of the PV panel sizing, wind turbine sizing and battery bank capacity on the system's reliability and economic performance were examined. Finally, a sensitivity analysis on its load consumption and renewable energy resource was performed to evaluate the robustness of economic analysis and identify which variable has the greatest impact on the results. The results demonstrate the techno-economic feasibility of implementing the solar-wind-battery system to supply power to this island.
Monocytes (Mo) and macrophages (Mϕ) are key components of the innate immune system and are involved in regulation of the initiation, development, and resolution of many inflammatory disorders. In ...addition, these cells also play important immunoregulatory and tissue-repairing roles to decrease immune reactions and promote tissue regeneration. Several lines of evidence have suggested a causal link between the presence or activation of these cells and the development of autoimmune diseases. In addition, Mo or Mϕ infiltration in diseased tissues is a hallmark of several autoimmune diseases. However, the detailed contributions of these cells, whether they actually initiate disease or perpetuate disease progression, and whether their phenotype and functional alteration are merely epiphenomena are still unclear in many autoimmune diseases. Additionally, little is known about their heterogeneous populations in different autoimmune diseases. Elucidating the relevance of Mo and Mϕ in autoimmune diseases and the associated mechanisms could lead to the identification of more effective therapeutic strategies in the future.
Background/Aims: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease with unclear molecular mechanisms. Our study intended to identify potential long non-coding RNAs ...(lncRNAs) and genes, and to determine the potential molecular mechanisms of NAFLD pathogenesis. Methods: The microarrays of GSE24031 and GSE57425 were downloaded from the Gene Expression Omnibus database. GSE24031 included 4 control and 4 model mice and GSE57425 included 3 control and 3 model mice on the basis of GPL1261 platform. Differentially expressed lncRNAs and mRNAs between control and NAFLD liver tissue were calculated. Gene ontology (GO), pathway enrichment analyses, co-expression network and PPI were performed to analyze the biological roles and pathways for the differentially expressed lncRNAs and mRNAs. Non-alcoholic steatohepatitis (NASH) rats were further chosen to investigate the key protein identified based on co-expression network and protein-protein interaction (PPI) network data. Results: A total of 6 significantly up-regulated and 39 down-regulated lncRNAs, 340 up-regulated and 281 down-regulated mRNAs were identified. LncRNA-mRNA co-expression network were analyzed to show a total of 16 key lncRNAs (node degree > 10) in NAFLD samples compared to control tissues. Three key protein identified on co-expression network and protein-protein interaction (PPI) network data were verified in NASH in vivo. The protein level of ATP-citrate lyase (Acly) was significantly increased while lncNONMMUT010685 and NONMMUT050689 in NAFLD samples, whose regulator gene was x-box binding protein 1 (XBP1) and receptor-interacting protein 1 kinase (RIPK1) respectively, were gradually reduced in NASH. Conclusion: In summary, we found a set of lncRNAs and mRNAs differentially expressed in the development of NAFLD. LncRNA Ttc39aos1 and Acly, may be crucial biomarkers for NAFLD. LncRNA NONMMUT010685 and NONMMUT050689, the regulator of XBP1 gene and RIPK1 gene respectively, played important roles in the development of NAFLD.
Acute kidney injury (AKI) is a destructive clinical condition induced by multiple insults including ischemic reperfusion, nephrotoxic drugs and sepsis. It is characterized by a sudden decline in ...renal function, in addition to excessive inflammation, oxidative stress and programmed cell death of renal tubular epithelial cells. RIPK1-mediated necroptosis plays an important role in AKI. In the present study, we evaluated the treatment effects of Compound-71 (Cpd-71), a novel RIPK1 inhibitor, by comparing with Necrostatin-1 (Nec-1), a classic RIPK1 inhibitor, which has several drawbacks like the narrow structure-activity relationship (SAR) profile, moderate potency and non-ideal pharmacokinetic properties,
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Our results showed that pretreatment of Cpd-71 attenuated cisplatin-induced renal injury, restored renal function and suppressed renal inflammation, oxidative stress and cell necroptosis. In addition, Cpd-71 inhibited renal damage while reducing the up-regulated serum creatinine (Cr) and blood urea nitrogen (BUN) levels in established AKI mice model. Consistently, we confirmed that Cpd-71 exhibited more effectively suppressive effect on cisplatin-induced renal tubular cell necroptosis than Nec-1, by physically binding to the allosteric type III ligand binding site of RIPK1, thereby reduced RIPK1 kinase activity, RIPK1/RIPK3 complex formation and phosphor-MLKL membrane translocation by molecular docking, Western blot, co-immunoprecipitation and cellular thermal shift assay (CETSA). Taken together, we currently showed that targeting RIPK1 with Cpd-71 may serve as a promising clinical candidate for AKI treatment.
•This meta-analysis addresses credibility concerns for online health information.•A collection of empirical studies addressing user-generated content was analyzed.•We synthesized 22 effect sizes ...drawn from empirical studies of 1346 participants.•Source credibility had no influence on perceived information credibility.•The platform where the information was posted might be a contingent factor.
The present study provides a meta-analysis of perceived credibility concerns for user-generated-online-health information. Past work yields inconsistent findings regarding whether high credible versus low credible sources would relate to perceived credibility of online health information. A collection of empirical studies was synthesized to reach an explanation of the conflicting findings. Analysis of 22 effect sizes with 1346 participants indicated that source credibility had no significant overall influence on perceived information credibility (r=0.03, n.s.). However, the variances across the studies suggest that the platform where the information was posted might be a contingent factor. Specifically, when user-generated health information was posted on a common website, high credible sources were significantly related to high perceived information credibility.
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