179 research outputs found

    Topological extension including quantum jump

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    Non-Hermitian (NH) systems and open quantum systems have always been regarded as reliable tools in dissipative modeling. Intriguingly, in order to reduce the model complexity, existing literature usually obtains an effective NH Hamiltonian by ignoring the quantum jumping terms in Lindblad master equation. However, there lacks investigation into the effects of discarded terms as well as the unified connection between these two approaches. In this study, we investigate the Su-Schrieffer-Heeger (SSH) model with collective loss and gain from a topological perspective. By employing the generalized Brillouin zone (GBZ) theory to the shape matrix, the jump absence topological properties exhibits consistency with traditional theory, while the transitions points may shift when jumping terms are involved. Our study provides qualitative analysis of the impact of quantum jumping terms and reveals their unique role in quantum systems

    Improved antibacterial performance using hydrogel-immobilized lysozyme as a catalyst in water

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    Silver nanoparticle-based catalysts are used extensively to kill bacteria in drinking water treatment. However secondary contamination and their high cost require scientists to seek alternatives with non-toxicity, high activity and low cost. In this article, we develop a new hydrogel-immobilized lysozyme (h-lysozyme) that shows excellent antibacterial performance, including high activity duration of up to 55 days, inhibition efficiency as high as 99.4%, good recycling capability of up to 11 cycles, a wide temperature window and extremely low concentration. The immobilized lysozyme displayed greatly improved bacterial inhibition with both Gram-negative E. coli and Gram-positive B. subtilis, which enables broad antibacterial applications in various water systems. In parallel, the non-toxic structure and high stability of the hlysozyme without additional contamination make it a promising alternative to nanoparticle catalysts fur use in drinking water purification

    Integrating the Local Property and Topological Structure in the Minimum Spanning Tree Brain Functional Network for Classification of Early Mild Cognitive Impairment

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    Abnormalities in the brain connectivity in patients with neurodegenerative diseases, such as early mild cognitive impairment (EMCI), have been widely reported. Current research shows that the combination of multiple features of the threshold connectivity network can improve the classification accuracy of diseases. However, in the construction of the threshold connectivity network, the selection of the threshold is very important, and an unreasonable setting can seriously affect the final classification results. Recent neuroscience research suggests that the minimum spanning tree (MST) brain functional network is helpful, as it avoids the methodological biases while comparing networks. In this paper, by employing the multikernel method, we propose a framework to integrate the multiple properties of the MST brain functional network for improving the classification performance. Initially, the Kruskal algorithm was used to construct an unbiased MST brain functional network. Subsequently, the vector kernel and graph kernel were used to quantify the two different complementary properties of the network, such as the local connectivity property and the topological property. Finally, the multikernel support vector machine (SVM) was adopted to combine the two different kernels for EMCI classification. We tested the performance of our proposed method for Alzheimer's Disease Neuroimaging Initiative (ANDI) datasets. The results showed that our method achieved a significant performance improvement, with the classification accuracy of 85%. The abnormal brain regions included the right hippocampus, left parahippocampal gyrus, left posterior cingulate gyrus, middle temporal gyrus, and other regions that are known to be important in the EMCI. Our results suggested that, combining the multiple features of the MST brain functional connectivity offered a better classification performance in the EMCI

    OsbZIP18, a Positive Regulator of Serotonin Biosynthesis, Negatively Controls the UV-B Tolerance in Rice

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    Serotonin (5-hydroxytryptamine) plays an important role in many developmental processes and biotic/abiotic stress responses in plants. Although serotonin biosynthetic pathways in plants have been uncovered, knowledge of the mechanisms of serotonin accumulation is still limited, and no regulators have been identified to date. Here, we identified the basic leucine zipper transcription factor OsbZIP18 as a positive regulator of serotonin biosynthesis in rice. Overexpression of OsbZIP18 strongly induced the levels of serotonin and its early precursors (tryptophan and tryptamine), resulting in stunted growth and dark-brown phenotypes. A function analysis showed that OsbZIP18 activated serotonin biosynthesis genes (including tryptophan decarboxylase 1 (OsTDC1), tryptophan decarboxylase 3 (OsTDC3), and tryptamine 5-hydroxylase (OsT5H)) by directly binding to the ACE-containing or G-box cis-elements in their promoters. Furthermore, we demonstrated that OsbZIP18 is induced by UV-B stress, and experiments using UV-B radiation showed that transgenic plants overexpressing OsbZIP18 exhibited UV-B stress-sensitive phenotypes. Besides, exogenous serotonin significantly exacerbates UV-B stress of OsbZIP18_OE plants, suggesting that the excessive accumulation of serotonin may be responsible for the sensitivity of OsbZIP18_OE plants to UV-B stress. Overall, we identified a positive regulator of serotonin biosynthesis and demonstrated that UV-B-stress induced serotonin accumulation, partly in an OsbZIP18-dependent manner

    Combination of Fluoride and SO2 Induce DNA Damage and Morphological Alterations in Male Rat Kidney

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    Background/Aims: We investigated the combined toxic effect of sodium fluoride (NaF) and sulfur dioxide (SO2) on kidney morphological changes and DNA damage in male Wistar rats. Methods: In this study we selected totally 96 male Wistar rats (12-week-old) then randomly group-housed them into four cages, treated with deionized water, NaF, SO2 and co-treatment of NaF and SO2 respectively. Morphological changes of kidney were detected by hematoxylin and eosin (H&E) staining at 2, 4, 6 and 8 weeks. Correspondingly, tailing ratio and comet length were measured by BAB Bs Comet Assay System, including DNA damage special unit were calculated to evaluate the grades of kidney DNA damage at the same time. Results: Treated groups showed a body weight decrease when compared to control group. However, no significant difference in the relative weight of kidney was found in all four groups. It is noteworthy that at 2, 4, 6 and 8 weeks after exposure, the morphological alteration of renal tubules were observed in all treated groups, especially in group-IV. Also, at 4 and 6 weeks, notable DNA damage was found in all treated groups, as assessed by significantly increasing trend of comet length tailing ratio. Conclusion: The study manifests that presence of NaF and SO2 will not only induce renal tissue lesions but also impact DNA integrity. In addition, this combined exposure exhibits a synergistic effect, characterizing a dose-dependence and time correlation. These findings may provide novel insights regarding perturbations of DNA damage and its functions as a potential new mechanism, by which cautious interpretation of NaF and SO2 co-exposure evolved in both animals and human beings is necessary
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