317 research outputs found

    VeriQR:A robustness verification tool for quantum machine learning models

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    Adversarial noise attacks present a significant threat to quantum machine learning (QML) models, similar to their classical counterparts. This is especially true in the current Noisy Intermediate-Scale Quantum era, where noise is unavoidable. Therefore, it is essential to ensure the robustness of QML models before their deployment. To address this challenge, we introduce VeriQR, the first tool designed specifically for formally verifying and improving the robustness of QML models, to the best of our knowledge. This tool mimics real-world quantum hardware’s noisy impacts by incorporating random noise to formally validate a QML model’s robustness. VeriQR supports exact (sound and complete) algorithms for both local and global robustness verification. For enhanced efficiency, it implements an under-approximate (complete) algorithm and a tensor network-based algorithm to verify local and global robustness, respectively. As a formal verification tool, VeriQR can detect adversarial examples and utilize them for further analysis and to enhance the local robustness through adversarial training, as demonstrated by experiments on real-world quantum machine learning models. Moreover, it permits users to incorporate customized noise. Based on this feature, we assess VeriQR using various real-world examples, and experimental outcomes confirm that the addition of specific quantum noise can enhance the global robustness of QML models. These processes are made accessible through a user-friendly graphical interface provided by VeriQR, catering to general users without requiring a deep understanding of the counter-intuitive probabilistic nature of quantum computing

    Rapid Screening and Preparative Isolation of Antioxidants from Alpinia officinarum

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    An efficient method using high-speed counter-current chromatography (HSCCC) coupled with DPPH-HPLC assay has been developed for rapid screening and preparative isolation of antioxidants from ethyl acetate fraction of Alpinia officinarum Hance. Target-guided by DPPH-HPLC assay, two antioxidants, galangin and kaempferide, were targeted and further separated with purities of 99.3% and 98.5% by HSCCC using petroleum ether–ethyl acetate–methanol–water (0.8 : 1 : 1 : 0.8, v/v) as the solvent system. The antioxidant activities of galangin and kaempferide were further evaluated by measuring their inhibiting effects on superoxide anion radical, hydroxyl radical, and hydrogen peroxide in different luminol chemiluminescence (CL) systems. As a result, galangin and kaempferide both showed potent antioxidant activities. Results of the present study indicated that the combinative method by offline coupling DPPH-HPLC and HSCCC could be widely applied for rapid screening and isolation of antioxidants from complex TCM extract

    Safety and efficacy of phage application in bacterial decolonisation:a systematic review

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    Colonisation by bacterial pathogens typically precedes invasive infection and seeds transmission. Thus, effective decolonisation strategies are urgently needed. The literature reports attempts to use phages for decolonisation. To assess the in-vivo efficacy and safety of phages for bacterial decolonisation, we performed a systematic review by identifying relevant studies to assess the in-vivo efficacy and safety of phages for bacterial decolonisation. We searched PubMed, Embase (Ovid), MEDLINE (Ovid), Web of Science, and the Cochrane Library to identify relevant articles published between Jan 1, 1990, and May 12, 2023, without language restrictions. We included studies that assessed the efficacy of phage for bacterial decolonisation in humans or vertebrate animal models. This systematic review is registered with PROSPERO, CRD42023457637. We identified 6694 articles, of which 56 (51 animal studies and five clinical reports) met the predetermined selection criteria and were included in the final analysis. The gastrointestinal tract (n=49, 88%) was the most studied bacterial colonisation site, and other sites were central venous catheters, lung, nose, skin, and urinary tract. Of the 56 included studies, the bacterial load at the colonisation site was reported to decrease significantly in 45 (80%) studies, but only five described eradication of the target bacteria. 15 studies reported the safety of phages for decolonisation. No obvious adverse events were reported in both the short-term and long-term observation period. Given the increasing life-threatening risks posed by bacteria that are difficult to treat, phages could be an alternative option for bacterial decolonisation, although further optimisation is required before their application to meet clinical needs.</p

    Impacts of Drought on Maize and Soybean Production in Northeast China During the Past Five Decades.

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    Climate change has a distinct impact on agriculture in China, particularly in the northeast, a key agriculture area sensitive to extreme hydroclimate events. Using monthly climate and agriculture data, the influence of drought on maize and soybean yields-two of the main crops in the region-in northeast China since 1961 to 2017 were investigated. The results showed that the temperature in the growing season increased by 1.0 °C from the period 1998-2017 to the period 1961-1980, while the annual precipitation decreased slightly. However, precipitation trends varied throughout the growing season (May-September), increasing slightly in May and June, but decreasing in July, August and September, associated with the weakening of the East Asian summer monsoon. Consequently, the annual and growing season drought frequency increased by 15%, and 25%, respectively, in the period 1998-2017 relative to the period 1961-1980. The highest drought frequency (55%) was observed in September. At the same time, the drought intensity during the growing season increased by 7.8%. The increasing frequency and intensity of drought had negative influences on the two crops. During moderate drought years in the period 1961-2017, 3.2% and 10.4% of the provincial maize and soybean yields were lost, respectively. However, during more severe drought years, losses doubled for soybean (21.8%), but increased more than four-fold for maize (14.0%). Moreover, in comparison to the period 1961-1980, a higher proportion of the yields were lost in the period 1998-2017, particularly for maize, which increased by 15% (increase for soybean was 2.4%). This change largely depends on increasing droughts in August and September, when both crops are in their filling stages. The impact of drought on maize and soybean production was different during different growth stages, where a strong relationship was noted between drought and yield loss of soybean in its filling stage. Given the sensitivity of maize and soybean yields in northeast China to drought, and the observed production trends, climate change will likely have significant negative impacts on productivity in the future

    A Novel Margin-Based Measure for Directed Hill Climbing Ensemble Pruning

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    Ensemble pruning is a technique to increase ensemble accuracy and reduce its size by choosing a subset of ensemble members to form a subensemble for prediction. Many ensemble pruning algorithms via directed hill climbing searching policy have been recently proposed. The key to the success of these algorithms is to construct an effective measure to supervise the search process. In this paper, we study the importance of individual classifiers with respect to an ensemble using margin theory proposed by Schapire et al. and obtain that ensemble pruning via directed hill climbing strategy should focus more on examples with small absolute margins as well as classifiers that correctly classify more examples. Based on this principle, we propose a novel measure called the margin-based measure to explicitly evaluate the importance of individual classifiers. Our experiments show that using the proposed measure to prune an ensemble leads to significantly better accuracy results compared to other state-of-the-art measures

    Using proteomic analysis to investigate uniconazole-induced phytohormone variation and starch accumulation in duckweed (Landoltia punctata)

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    KEGG pathway analysis of the annotated proteins. The pathway, number of annotated proteins, and pathway ID were listed in the table. (XLSX 15 kb

    The effects of yam gruel on lowering fasted blood glucose in T2DM rats

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    © 2020 Xinjun Lin et al., published by De Gruyter 2020. There is increasing evidence of the linkage between type 2 diabetes mellitus (T2DM) and gut microbiota. Based on our previous studies, we investigated the hypoglycemic mechanisms of yam gruel to provide a scientific basis for its popularization and application. Wistar rats were randomly divided into control and T2DM model groups. Rats in the model group were stimulated by a high-sugar/high-fat diet combined with an intraperitoneal injection of streptozotocin to induce T2DM. The T2DM rats were further subdivided randomly into three groups: (1) DM, (2) DM + yam gruel, and (3) DM + metformin. After 4 weeks of intervention, the changes in gut microbiota, short-chain fatty acids (SCFAs) (acetic acid, propionic acid, and butyric acid), the expression of G protein-coupled receptor 43 (GPR43), glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and fasted blood glucose (FBG) levels were observed. Yam gruel intervention elevated the abundance of probiotic bacteria and increased the expression of SCFAs, GPR43 receptor, GLP-1, and PYY. It also reduced FBG levels. We conclude that yam gruel can lower FBG by promoting the growth of probiotic bacteria, increasing the content of SCFAs, and enhancing the expression of GPR43 receptor to increase the content of GLP-1 and PYY in serum

    Effects of Dioscorea polystachya \u27yam gruel\u27 on the cognitive function of diabetic rats with focal cerebral ischemia-reperfusion injury via the gut-brain axis

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    © 2020 Pang et al. Published by IMR press. Focal cerebral ischemia-reperfusion injury is closely related to hyperglycemia and gut microbiota imbalance, while gut microbiota contributes to the regulation of brain function through the gut-brain axis. Previous studies in patients with diabetes have found that \u27yam gruel\u27 is a classic medicated diet made from Dioscorea polystachya, increases the content of Bifidobacterium, regulates oxidative stress, and reduces fasting blood glucose levels. The research reported here investigated the effects of \u27yam gruel\u27 on the cognitive function of streptozotocin-induced diabetic rats with focal cerebral ischemia-reperfusion injury and explored the mechanism underlying the role of the gut-brain axis in this process. \u27Yam gruel\u27 was shown to improve cognitive function as indicated by increased relative content of probiotic bacteria, and short-chain fatty acids in the intestinal tract and cerebral cortex reduced oxidative stress and inflammatory response and promotion of the expression of neurotransmitters and brain-derived neurotrophic factor. Thus, it is concluded that \u27yam gruel\u27 has a protective effect on cognitive function via a mechanism related to the gut-brain axis

    Clinical features and risk factors of sepsis-induced cardiomyopathy in children with sepsis

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    Objective To investigate the clinical features and risk factors of sepsis-induced cardiomyopathy in children with sepsis, aiming to provide reference for enhancing the diagnosis and treatment levels of clinicians. Methods Clinical data of children with sepsis were retrospectively analyzed. All patients were divided into the sepsis-induced cardiomyopathy group and non-sepsis-induced cardiomyopathy group according to whether sepsis-induced cardiomyopathy occurred.Clinical characteristics and outcomes were compared between two groups. The risk factors of sepsis-induced cardiomyopathy were analyzed. Results Three hundred and ninty-eight children with sepsis were included in this study, and the incidence of sepsis-induced cardiomyopathy was 15.58%(62/398). The age of children in the sepsis-induced cardiomyopathy group was 49 (18, 108) months, older than 19 (6, 52) months in the non-sepsis-induced cardiomyopathy group. The incidence of septic shock in the sepsis-induced cardiomyopathy group was 83.87%(52/62), which was higher than 42.56% (143/336) in the non-sepsis-induced cardiomyopathy group. The mortality rate in the sepsis-induced cardiomyopathy group was 29.03% (18/62), significantly higher than 14.58% (49/336) in the non-sepsis-induced cardiomyopathy group. All differences were statistically significant (all P &lt; 0.05).Multivariate Logistic regression analysis showed that the influence of age on sepsis-induced cardiomyopathy was statistically significant (OR=1.010, 95%CI 1.003-1.017, P = 0.006). The higher the lactic acid level, the higher the risk of sepsis-induced cardiomyopathy, with statistical significance (OR=1.163, 95%CI 1.034-1.308, P = 0.012). The higher the cTnI level, the higher the risk of sepsis-induced cardiomyopathy, with statistical significance (OR=9.929, 95%CI 4.651-21.197, P &lt; 0.001). Conclusions Compared with children with non-sepsis-induced cardiomyopathy, children with sepsis-induced cardiomyopathy are more prone to septic shock and have higher mortality. Age, lactic acid and cTnI levels are the independent influencing factors for sepsis-induced cardiomyopathy in children
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