30 research outputs found
OMAE 2009-79849 STRUCTURAL SAFETY ASSESSMENT OF EXISTING ICE-RESISTANT JACKET PLATFORMS IN ICE ZONE
ABSTRACT Until now dozens of offshore structures have been deployed in Bohai bay since the first drilling platform was erected in 1965. The oil and natural gas resources of Bohai Bay are mainly marginal oil fields. It is necessary to build both ice-resistant and economical offshore platforms. Full-scale measurement for many years shows the design of some ice-resistant platforms is not so sophisticated, the most significant is that ice induced vibration is the main which has caused harmful accidents in Liaodong bay of Bohai. In order to ensure security operation, structural safety assessment and life extension become key problems. In this paper, failure modes of ice resist jacket platforms, the related failure evaluation criteria, and risk grade are treated. Combined with monitoring data of ice loads, assessment strategy is presented. Lastly, as an application example, safety assessments of a practical platform in Bohai Bay are carried on
Making Sense of Institutional Change in China: The Cultural Dimension of Economic Growth and Modernization
Building on a new model of institutions proposed by Aoki and the systemic approach to economic civilizations outlined by Kuran, this paper attempts an analysis of the cultural foundations of recent Chinese economic development. I argue that the cultural impact needs to be conceived as a creative process that involves linguistic entities and other public social items in order to provide integrative meaning to economic interactions and identities to different agents involved. I focus on three phenomena that stand at the center of economic culture in China, networks, localism and modernism. I eschew the standard dualism of individualism vs. collectivism in favour of a more detailed view on the self in social relationships. The Chinese pattern of social relations, guanxi, is also a constituent of localism, i.e. a peculiar arrangement and resulting dynamics of central-local interactions in governing the economy. Localism is balanced by culturalist controls of the center, which in contemporary China builds on the worldview of modernism. Thus, economic modernization is a cultural phenomenon on its own sake. I summarize these interactions in a process analysis based on Aoki's framework
A Blockchain-Based Privacy Information Security Sharing Scheme in Industrial Internet of Things
Due to the competitive relationship among different smart factories, equipment manufacturers cannot integrate the private information of all smart factories to train the intelligent manufacturing equipment fault prediction model and improve the accuracy of intelligent manufacturing equipment fault detection. The use of a low fault recognition rate model for smart factories will cause additional losses for them. In this work, we propose a blockchain-based privacy information security sharing scheme in Industrial Internet of Things (IIoT) to solve the sharing problem of private information in smart factories. Firstly, we abstract smart factories as edge nodes and build decentralized, distributed trusted blockchain networks based on Ethereum clients on simulated edge devices and propose an Intelligent Elliptic Curve Digital Signature Algorithm (IECDSA) to guarantee the ownership of shared information by edge nodes. Secondly, we propose the Reputation-based Delegated Proof of Stake (RDPoS) consensus algorithm to improve the security and reliability of the Delegated Proof of Stake (DPoS) consensus algorithm. Furthermore, we design and implement an incentive mechanism based on information attributes to increase the motivation of edge nodes to share information. Finally, the proposed solution is simulated. Through theoretical and simulation experiments, it is proved that the blockchain-based privacy information security sharing scheme in IIoT can improve the enthusiasm of edge nodes to share information on the premise of ensuring the security of information sharing
Saliniquinone Derivatives, Saliniquinones G−I and Heraclemycin E, from the Marine Animal-Derived Nocardiopsis aegyptia HDN19-252
Four new anthraquinone derivatives, namely saliniquinones G−I (1–3) and heraclemycin E (4), were obtained from the Antarctic marine-derived actinomycete Nocardiopsis aegyptia HDN19-252, guided by the Global Natural Products Social (GNPS) molecular networking platform. Their structures, including absolute configurations, were elucidated by extensive NMR, MS, and ECD analyses. Compounds 1 and 2 showed promising inhibitory activity against six tested bacterial strains, including methicillin-resistant coagulase-negative staphylococci (MRCNS), with MIC values ranging from 3.1 to 12.5 μM
Mesenchymal stem cells protect against sepsis-associated acute kidney injury by inducing Gal-9/Tim-3 to remodel immune homeostasis
AbstractObjective The present study investigated the specific mechanism by which mesenchymal stem cells (MSCs) protect against sepsis-associated acute kidney injury (SA-AKI).Methods Male C57BL/6 mice underwent cecal ligation and puncture surgery to induce sepsis and then received either normal IgG or MSCs (1 × 106 cells, intravenously) plus Gal-9 or soluble Tim-3 3 h after surgery.Results After cecal ligation and puncture surgery, the mice injected with Gal-9 or MSCs plus Gal-9 had a higher survival rate than the mice in the IgG treatment group. Treatment with MSCs plus Gal-9 decreased serum creatinine and blood urea nitrogen levels, improved tubular function recovery, reduced IL-17 and RORγt levels and induced IL-10 and FOXP3 expression. Additionally, the Th17/Treg cell balance was altered. However, when soluble Tim-3 was used to block the Gal-9/Tim-3 pathway, the septic mice developed kidney injury and exhibited increased mortality. Treatment with MSCs plus soluble Tim-3 blunted the therapeutic effect of MSCs, inhibited the induction of Tregs, and suppressed the inhibition of differentiation into Th17 cells.Conclusion Treatment with MSCs significantly reversed the Th1/Th2 balance. Thus, the Gal-9/Tim-3 pathway may be an important mechanism of MSC-mediated protection against SA-AKI
Hexarelin alleviates apoptosis on ischemic acute kidney injury via MDM2/p53 pathway
Abstract Introduction Hexarelin exhibits significant protection against organ injury in models of ischemia/reperfusion (I/R)-induced injury (IRI). Nevertheless, the impact of Hexarelin on acute kidney injury (AKI) and its underlying mechanism remains unclear. In this study, we investigated the therapeutic potential of Hexarelin in I/R-induced AKI and elucidated its molecular mechanisms. Methods We assessed the protective effects of Hexarelin through both in vivo and in vitro experiments. In the I/R-induced AKI model, rats were pretreated with Hexarelin at 100 μg/kg/d for 7 days before being sacrificed 24 h post-IRI. Subsequently, kidney function, histology, and apoptosis were assessed. In vitro, hypoxia/reoxygenation (H/R)-induced HK-2 cell model was used to investigate the impact of Hexarelin on apoptosis in HK-2 cells. Then, we employed molecular docking using a pharmmapper server and autodock software to identify potential target proteins of Hexarelin. Results In this study, rats subjected to I/R developed severe kidney injury characterized by tubular necrosis, tubular dilatation, increased serum creatinine levels, and cell apoptosis. However, pretreatment with Hexarelin exhibited a protective effect by mitigating post-ischemic kidney pathological changes, improving renal function, and inhibiting apoptosis. This was achieved through the downregulation of conventional apoptosis-related genes, such as Caspase-3, Bax and Bad, and the upregulation of the anti-apoptotic protein Bcl-2. Consistent with the in vivo results, Hexarelin also reduced cell apoptosis in post-H/R HK-2 cells. Furthermore, our analysis using GSEA confirmed the essential role of the apoptosis pathway in I/R-induced AKI. Molecular docking revealed a strong binding affinity between Hexarelin and MDM2, suggesting the potential mechanism of Hexarelin’s anti-apoptosis effect at least partially through its interaction with MDM2, a well-known negative regulator of apoptosis-related protein that of p53. To validate these findings, we evaluated the relative expression of MDM2 and p53 in I/R-induced AKI with or without Hexarelin pre-administration and observed a significant suppression of MDM2 and p53 by Hexarelin in both in vivo and in vitro experiments. Conclusion Collectively, Hexarelin was identified as a promising medication in protecting apoptosis against I/R-induced AKI