332 research outputs found

    Effect of ethanol extract of Punica granatum L against Freund’s complete adjuvant-induced arthritis in rats

    Get PDF
    Purpose: To investigate the protective effect of ethanol extract of P. granatum against arthritis in rat model. Methods: Twenty-six adult male Wistar rats (120 - 150 g) were separated into four groups (n = 6): normal control, arthritic control and two treatment groups. With the exception of normal control group, arthritis was induced by intraplantar administration of Freund’s complete adjuvant (FCA) on the 1st day of drug administration. The arthritic control group was not treated, while the treatment groups received extract orally at 500 or 750 mg/kg for the period of 4 weeks and at the end of each week, paw volume, thermal hyperalgesia, arthritic score and mechanical nociceptive threshold were performed to assess arthritis. Biochemical indicators and inflammatory cytokines in serum were determined using standard procedures. Results: There was significant decrease in paw volume and arthritic score; paw withdrawal latency was enhanced in extract-treated groups, compared to arthritic control group (p < 0.05). Furthermore, ALT, AST and ALP levels, as well as RF and MDA activities decreased significantly with extract treatment, compared with arthritic control group (p < 0.05). Treatment with the extract attenuated the altered level of interleukin 1β (IL-1β) and TNF-α levels in arthritic rats. Histological examination showed that treatment with the extract significantly reversed histological changes induced by arthritis. Conclusion: The results reveal that the beneficial effect of ethanol extract of P. granatum against FCAinduced arthritis is due to its ability to reduce the levels of inflammatory cytokines

    Detailed crustal deformation in the Ailaoshan Orogenic Belt revealed by receiver functions from a dense array

    Get PDF
    The Ailaoshan Orogenic Belt (AOB), located at the southeastern boundary of the Tibetan Plateau, is an ideal place for investigating the mechanisms of lateral growth of Tibet. Using the data recorded by a dense seismic array across the Ailaoshan belt, we investigate the detailed lateral variations of crustal anisotropy on the basis of Pms phase of receiver functions. Remarkable crustal anisotropy is observed throughout this study region with a mean delay time of 0.33 ± 0.19 s, indicating the anisotropy primarily originates in the middle-lower crust. The fast directions beneath the AOB including the Ailaoshan-Red River shear zone (ARRSZ) and its western low-grade metamorphic unit generally align with the NW-SE strike of ARRSZ. The weak anisotropy in the South China Block (SCB) argues that the block is relatively stable, with limited internal deformation. Meanwhile, the anisotropy beneath the western boundary of the SCB is strong, and the N-S oriented fast direction is influenced by both the crustal stress and Xiaojiang Fault. Combining the high Vp/Vs and significant lateral variations of crustal anisotropy parameters, we suggest that the strike-slip motion along the ARRSZ induces the partial melting and pronounced anisotropy in the middle-lower crust of AOB, without the presence of crustal flow. The differences between crustal and mantle anisotropy indicate crust-mantle decoupling deformation of the AOB, supporting the block extrusion model occurring only in the crustal scale as the primary deformation pattern

    P-wave velocity structure and implications for magmatism and metallogenesis in the southern Altaids: Constraint from wide-angle seismic data along the Altai-Eastern Tianshan traverse

    Get PDF
    Altaids in the Central Asian Orogenic Belt (CAOB) is one of the world’s largest orogenic belts containing mineral deposits. Together with the Junggar terrain they open an important window to study the Paleozoic tectonic evolution of the CAOB. In this paper, we analyze a 637-km-long wide-angle refraction/reflection seismic profile across the Altai-Eastern Tianshan orogenic belt in the southern Altaids, conducted in September 2018 using 10 large explosive charges fired in drilled holes. We use a traveltime inversion method to reconstruct the lithospheric P-wave velocity structure along the profile. The lithosphere is composed of a 43-55-km-thick crust, a ∼10-km-thick crust-mantle transition layer beneath the Altai Mountain, and a ∼25-km-thick layer of lithospheric mantle. The results clearly reveal: a prominent Moho uplift beneath the Yemaquan Island Arc, two major crustal-scale low-velocity anomalies (LVAs) beneath the Yemaquan Arc and Bogda Mountain, and three high-velocity anomalies (HVAs) near the surface around the Kalatongke, Yemaquan and Kalatage mining areas. We hypothesize that the subduction of the Paleo-Asian Ocean occurred with strong mantle upwelling. We suggest that continued compression of the Paleo-Asian Ocean causes the delamination of lithosphere, as well as asthenospheric material upwelling and magma underplating into the crust. Consistently, Paleozoic mafic-ultramafic rocks and mantle-derived minerals related to gold, copper and nickel deposits, are widely extended in the area. Our results show that the P-wave velocity-depth curves for deeper depths (>30 km) in the southern Altai and Junggar Basin are close to those of the continental arcs and global continent average. Despite powerful Paleozoic subduction activity, orogeny and volcanism strongly modified the lower crust in the region, part of ancient continental crust was still preserved below the southern Altai and Junggar Basin. In addition, the upper part (depth 5–30 km) of the velocity-depth curve for the Junggar Basin is close to that of the Costa Rica volcanic front and the British Columbia accreted terrain, suggesting that Paleozoic orogenic activity has intensively reconstructed the upper-middle crust beneath the Junggar Basin

    Defining Biological Networks for Noise Buffering and Signaling Sensitivity Using Approximate Bayesian Computation

    Get PDF
    Reliable information processing in cells requires high sensitivity to changes in the input signal but low sensitivity to random fluctuations in the transmitted signal. There are often many alternative biological circuits qualifying for this biological function. Distinguishing theses biological models and finding the most suitable one are essential, as such model ranking, by experimental evidence, will help to judge the support of the working hypotheses forming each model. Here, we employ the approximate Bayesian computation (ABC) method based on sequential Monte Carlo (SMC) to search for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. By systematically analyzing three-component circuits, we rank these biological circuits and identify three-basic-biological-motif buffering noise while maintaining sensitivity to long-term changes in input signals. We discuss in detail a particular implementation in control of nutrient homeostasis in yeast. The principal component analysis of the posterior provides insight into the nature of the reaction between nodes

    Learning to Branch in Combinatorial Optimization with Graph Pointer Networks

    Full text link
    Branch-and-bound is a typical way to solve combinatorial optimization problems. This paper proposes a graph pointer network model for learning the variable selection policy in the branch-and-bound. We extract the graph features, global features and historical features to represent the solver state. The proposed model, which combines the graph neural network and the pointer mechanism, can effectively map from the solver state to the branching variable decisions. The model is trained to imitate the classic strong branching expert rule by a designed top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. Our approach also outperforms the state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances

    A novel conceptual design of modularised offshore green hydrogen system

    Get PDF
    As a signatory to the Paris Agreement, the UK is committed to contribute efforts to prevent global temperature increase. The UK set its policies and proposals to meet zero net strategy by 2050. Offshore green hydrogen is one promising approach to transfer offshore wind energy to onshore demand areas due to its clean and high-power density. The UK is accelerating towards offshore green hydrogen and has made the price of green hydrogen competitive in the marketplace. The bottleneck of offshore green hydrogen system (OGHS) is the cost of scaling up hydrogen production in the current stage. Innovate designs of hydrogen production system may bring breakthrough to the cost when scaling up the OGHS. This study proposed a centralised OGHS which integrates with modularised production, storage, and offloading units using electricity coming from offshore wind farms. The paper offers an overview of the current situation and development of hydrogen platform and offshore wind farm for supporting the design of offshore platform as well as highlights the key features of technologies used by the different components of the OGHS, through a thorough literature review, including state-of-the-art technical reports and journal papers. A conceptual design of the proposed modularised OGHS is illustrated with a recommendation of site selection. Equipment layout of the OGHS distributed on a floating supporting structure is designed based on a case study of a 200-MW floating wind farm. Stability of the OGHS floating platform is analysed to verify safety of the in the case study, and linear hydrodynamics analysis is simulated based on linear potential theory

    Involvement of Endoplasmic Reticulum Stress in Myocardial Apoptosis of Streptozocin-Induced Diabetic Rats

    Get PDF
    Apoptosis plays critical role in diabetic cardiomyopathy and endoplasmic reticulum stress (ERS) is one of intrinsic apoptosis pathways. For previous studies have shown that endoplasmic reticulum become swell in diabetic myocardium and ERS was involved in diabetes mellitus and heart failure, this study aimed to demonstrate whether ERS was induced in myocardium of streptozocin (STZ)-induced diabetic rats. We established type 1 diabetic rat model with STZ intraperitoneal injection, used echocardiographic evaluation, hematoxylin-eosin staining and the terminal deoxynucleotidyl transferase-mediated DNA nick-end labeling staining to identify the existence of diabetic cardiomyopathy and enhanced apoptosis in the diabetic heart. We performed immunohistochemistry, Western blot and real time PCR to analysis two hallmarks of ERS, glucose regulated protein78 (Grp78) and Caspase12. We found both Grp78 and Caspase12 had enhanced expression in protein and mRNA levels in diabetic myocardium than normal rat’s, and Caspase12 was activated in diabetic heart. Those results suggested that ERS was induced in STZ-induced diabetic rats’ myocardium, and ERS-associated apoptosis took part in the pathophysiology of diabetic cardiomyopathy
    • …
    corecore