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基于LightGBM的拖曳系统动力响应预报方法
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作者 董磊磊 张鑫 +2 位作者 豆东阳 李豹 张崎 《舰船科学技术》 北大核心 2024年第3期34-40,共7页
针对传统数值仿真计算方法耗时长、占用计算机资源多等缺点,提出基于LightGBM算法的拖曳系统动力响应进行评估的回归预测模型,以已有的OrcaFlex数值模拟得到的数据为样本,以拖曳系统上的海洋环境条件、拖船航速和下放缆长为特征,以动力... 针对传统数值仿真计算方法耗时长、占用计算机资源多等缺点,提出基于LightGBM算法的拖曳系统动力响应进行评估的回归预测模型,以已有的OrcaFlex数值模拟得到的数据为样本,以拖曳系统上的海洋环境条件、拖船航速和下放缆长为特征,以动力响应为目标,引入LightGBM算法,对拖曳缆顶端张力最大值等动力响应进行预测分析。与传统数值模拟方法相比,LightGBM算法在保证结果准确性的同时大幅度提高了计算效率。通过与随机森林(RF)、极限梯度提升(XGBoost)算法相比,其准确度和计算效率的表现更好。最后提出了贝叶斯参数优化的LightGBM算法,准确度进一步提高,为提前采取措施保障拖曳系统的作业安全提供了一条高效的技术途径,同时为建立拖曳系统数字孪生体提供了有力的技术支撑。 展开更多
关键词 拖曳系统 贝叶斯优化 LightGBM 动力响应
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Erratum to “The enriched gut commensal Faeciroseburia intestinalis contributes to the anti-metabolic disorders effects of the Ganoderma meroterpene derivative” [Food Science and Human Wellness 11 (2022) 85-96]
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作者 Shanshan Qiao Kai Wang +5 位作者 Chang liu Nan Zhou li bao Jun Wang Shuangjiang liu Hongwei liu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3718-3718,共1页
The authors were contacted after publication to request a replacement of Fig.2M in the manuscript.Unfortunately,the authors inadvertently used an image of the model(Vehicle)group liver histopathology section that matc... The authors were contacted after publication to request a replacement of Fig.2M in the manuscript.Unfortunately,the authors inadvertently used an image of the model(Vehicle)group liver histopathology section that matches an image published in Fig.2D of Cell Reports(Volume 26,Issue 1,pages 222–235.e5). 展开更多
关键词 enriched HUMAN image
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Effect of Modified Biochar with Organic Fertiliser on the Growth and Development of Chinese Rose
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作者 liyuan Mu Hongyin Zhou +4 位作者 Junlei Wang Sijing Sun Haichan Yang Naiming Zhang li bao 《Advances in Bioscience and Biotechnology》 CAS 2024年第6期344-359,共16页
In order to reduce the waste of resources and environmental pollution caused by excessive application of chemical fertilizers, improve the utilization rate of fertilizers, and promote the large-scale and high-quality ... In order to reduce the waste of resources and environmental pollution caused by excessive application of chemical fertilizers, improve the utilization rate of fertilizers, and promote the large-scale and high-quality development of the Chinese rose industry. In this experiment, corn stover biochar, phosphoric acid modified biochar and organic fertilizer were used as test materials, and the effects of mixed application of modified biochar and organic fertilizer on the growth and development of Chinese rose as well as soil physicochemical properties were investigated by using the method of pot planting test. The results showed that modified biochar with organic fertilizer had the most significant effect on the enhancement of soil pH, organic matter content and soil carbon-to-nitrogen ratio. After 120 d of planting, modified biochar with organic fertilizer had the most significant effect on the enhancement of plant height and crown width of Chinese rose;both organic fertilizer and modified biochar with organic fertilizer significantly increased the chlorophyll content of Chinese rose. The number of flowers and the number of branches were the highest in the modified biochar with organic fertilizer treatment. In conclusion, the application of modified biochar with organic fertilizer can better improve the soil pH, and increase the soil organic matter content and carbon-to-nitrogen ratio to change the biological traits of Chinese rose. The results of this study provide a theoretical basis for the reduction of chemical fertilizers and the resource utilization of agricultural wastes and guarantee the sustainable development of the cut flower industry. 展开更多
关键词 BIOCHAR Modified Biochar Chinese Rose Organic Fertiliser
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无人机LiDAR免控制测量技术在1∶10000 DEM更新中的应用
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作者 王辉 李宝 方庆晨 《城市勘测》 2024年第5期150-154,共5页
在安徽省1∶10000基础地理信息数据更新工程DEM局部更新工作中,针对外业中控制点布设工作量大、难度高的特点,研究无人机LiDAR测量技术生产DEM的免控制技术方法,利用激光点云分类结果中提取的可靠地面点,建立高程拟合模型,拟合转换点云... 在安徽省1∶10000基础地理信息数据更新工程DEM局部更新工作中,针对外业中控制点布设工作量大、难度高的特点,研究无人机LiDAR测量技术生产DEM的免控制技术方法,利用激光点云分类结果中提取的可靠地面点,建立高程拟合模型,拟合转换点云高程,生产DEM。并与传统通过实测控制点进行点云高程拟合生产的DEM成果精度比较。研究结果表明:利用免控制技术方法生产的DEM精度可以满足安徽省1∶10000 DEM更新要求。 展开更多
关键词 激光雷达点云 数字高程模型 无人机 可靠地面点
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PJM电力市场风险管控措施及对南方区域的建议 被引量:2
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作者 王子强 李豹 +4 位作者 杜哲宇 季天瑶 黄佳玺 龙志豪 荆朝霞 《南方电网技术》 CSCD 北大核心 2024年第1期28-37,68,共11页
电力市场改革的深化对电网运行风险管控提出了新的要求。通过总结PJM(Pennsylvania-New Jersey-Maryland)电力市场的风险管控策略,从两个方面分析其电力系统物理运行风险管控策略:包含长期、短期和实时的风险事故发生前措施,执行紧急中... 电力市场改革的深化对电网运行风险管控提出了新的要求。通过总结PJM(Pennsylvania-New Jersey-Maryland)电力市场的风险管控策略,从两个方面分析其电力系统物理运行风险管控策略:包含长期、短期和实时的风险事故发生前措施,执行紧急中断与恢复的风险事故发生后措施;从日前的可靠性机组组合、与电能量市场联合优化的辅助服务市场、中长期的容量市场和输电权市场四个方面分析其基于电力市场的风险管控策略。并将其与南方电网现有风险管控措施相对比,提出了进行多时段风险评估、采取调度-市场相结合的管控风险手段、建设完备的市场体系、成立风险委员会等多方面建议。 展开更多
关键词 风险管控 PJM电力市场 资源充足性分析 可靠性协调 可靠性机组组合
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Amelioration of metabolic disorders by a mushroom-derived polyphenols correlates with the reduction of Ruminococcaceae in gut of DIO mice 被引量:7
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作者 li Sun li bao +4 位作者 Dorji Phurbu Shanshan Qiao Shanshan Sun Yangzom Perma Hongwei liu 《Food Science and Human Wellness》 SCIE 2021年第4期442-451,共10页
A polyphenolic alkaloid-enriched extract(PAE)was prepared from the fruiting bodies of a wild edible mushroom Sarcodon leucopus.Oral administration of PAE reduced hyperglycemia,hyperlipidemia,hepatic steatosis,and LPS-... A polyphenolic alkaloid-enriched extract(PAE)was prepared from the fruiting bodies of a wild edible mushroom Sarcodon leucopus.Oral administration of PAE reduced hyperglycemia,hyperlipidemia,hepatic steatosis,and LPS-related infl ammation in high fat diet-induced obese(DIO)mice.Furthermore,we show that PAE produces taxonomic and predicted functional changes in the gut microbiome of DIO mice.A signifi cant decrease in the family of Ruminococcaceae,especially the secondary bile acid-producing bacteria of Intestinimonas and Anaerotruncus,is detected in the gut microbiome of PAE-treate mice.Accordingly,reductions of deoxycholic acid and lithocholic acid are found in the feces of PAE-treated DIO mice,which benefi ts for the intestinal integrity and the reduction of infl ammation.A gut microbiota related mechanism for the anti-metabolic syndrome effects of the PAE is proposed.We suppose the polyphenolic alkaloid extract from S.leucopus be a new and benefi cial prebiotic regulating glucose and lipid metabolisms. 展开更多
关键词 Sarcodon leucopus Polyphenolic alkaloids Metabolic syndrome Gut microbiota Ruminococcaceae
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Three New Heptelidic Acid Derivatives from the Culture of Mushroom Lentinellus ursinus 被引量:3
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作者 li liu Jun-Jie Han +3 位作者 Tian-Shun Xu Rui-Xing liu li bao Hong-Wei liu 《Natural Products and Bioprospecting》 CAS 2018年第5期355-360,共6页
Three new heptelidic acid derivatives(1-3)including two new dimeric esters and two known heptelidic acid analogues(4 and 5)were isolated from the solid culture of mushroom Lentinellus ursinus.The structures of new com... Three new heptelidic acid derivatives(1-3)including two new dimeric esters and two known heptelidic acid analogues(4 and 5)were isolated from the solid culture of mushroom Lentinellus ursinus.The structures of new compounds were confirmed by the analysis of NMR and HRESIMS spectroscopic data.The biosynthetic origin of compounds 1-5 was postulated.Compounds 1-5 exhibited no antibacterial activity against Staphylococcus aureus and Escherichia coli at the dose of 100 μM. 展开更多
关键词 Lentinellus ursinus Heptelidic acid derivatives Biosynthetic pathway
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The enriched gut commensal Faeciroseburia intestinalis contributes to the anti-metabolic disorders effects of the Ganoderma meroterpene derivative 被引量:1
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作者 Shanshan Qiao Kai Wang +5 位作者 Chang liu Nan Zhou li bao Jun Wang Shuangjiang liu Hongwei liu 《Food Science and Human Wellness》 SCIE 2022年第1期85-96,共12页
Previous study demonstrated that Ganoderma meroterpene derivative(GMD)increased the abundance of butyrate-producing bacteria in gut and subsequently delivered anti-metabolic disorder effect of host.To specify the key ... Previous study demonstrated that Ganoderma meroterpene derivative(GMD)increased the abundance of butyrate-producing bacteria in gut and subsequently delivered anti-metabolic disorder effect of host.To specify the key commensal bacteria associating with the beneficial effects,we tried to isolate and compare the microbiota from the cecal samples of GMD-and vehicle-treated ob/ob mice,and further identified butyrate-producing bacterial strains.It was found that Faeciroseburia intestinalis was enriched and 11 strains affiliated to F.intestinalis were cultivated from the gut of GMD-treated mice.In vitro assay attested butyrate production by representative strain of F.intestinalis.Oral administration with F.intestinalis further demonstrated its benefits on regulating hyperglycemia and hyperlipidemia,on decreasing plasma lipopolysaccharide(LPS)and inflammation,and on improving hepatic injuries.Treatment with F.intestinalis effectively enhanced the level of gut butyrate,which subsequently ameliorated the intestinal barrier function and activated epithelial PPAR-γ signaling pathway to regulate microbiome homeostasis in gut.Our study demonstrated that the causal relationship between the butyrate-producing bacteria and the GMD's therapeutic effects and confirmed the important function of the butyrate-producing F.intestinalis in maintaining host metabolism homeostasis. 展开更多
关键词 Faeciroseburia intestinalis Ganoderma meroditerpene derivative Gut microbiome BUTYRATE HYPOGLYCEMIA HYPOLIPIDEMIA
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Change of tumor-infiltrating lymphocyte of associating liver partition and portal vein ligation for staged hepatectomy for hepatocellular carcinoma 被引量:1
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作者 Wei Wang Zhen-Feng Deng +6 位作者 Ji-Long Wang ling Zhang li bao Bang-Hao Xu Hai Zhu Ya Guo Zhang Wen 《World Journal of Gastrointestinal Surgery》 SCIE 2022年第9期1008-1025,共18页
BACKGROUND The role of tumor-infiltrating lymphocytes(TILs)in the growth and progression of hepatocellular carcinoma(HCC)has attracted widespread attention.AIM To evaluate the feasibility of associating liver partitio... BACKGROUND The role of tumor-infiltrating lymphocytes(TILs)in the growth and progression of hepatocellular carcinoma(HCC)has attracted widespread attention.AIM To evaluate the feasibility of associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)for massive HCC by exploring the role of TIL in the tumor microenvironment.METHODS Fifteen massive HCC patients who underwent ALPPS treatment and 46 who underwent hemi-hepatectomy were selected for this study.Propensity score matching was utilized to match patients in ALPPS and hemi-hepatectomy groups(1:1).Quantitative analysis of TILs in tumor and adjacent tissues between the two groups was performed by immunofluorescence staining and further analyses with oncological characteristics.In the meantime,trends of TILs in peripheral blood RESULTS Continuous measurement of tumor volume and necrosis volume showed that the proportion of tumor necrosis volume on the seventh day after stage-I ALPPS was significantly higher than the pre-operative value(P=0.024).In the preoperative period of stage-I ALPPS,the proportion of tumor necrosis volume in the high CD8+T cell infiltration group was significantly higher than that in the low group(P=0.048).CONCLUSION TIL infiltration level maintained a dynamic balance during the preoperative period of ALPPS.Compared with right hemi-hepatectomy,the ALPPS procedure does not cause severe immunosuppression with the decrease in TIL infiltration and pathological changes in immune components of peripheral blood.Our results suggested that ALPPS is safe and feasible for treating massive HCC from the perspective of immunology.In addition,high CD8+T cell infiltration is associated with increasing tumor necrosis in the perioperative period of ALPPS. 展开更多
关键词 Associating liver partition and portal vein ligation for staged hepatectomy Tumor-infiltrating lymphocytes Multiplexed immunohistochemistry Tumor necrosis
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基于时间感知主导资源公平的边缘函数计算负载调度算法
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作者 李宝 朱姝 +2 位作者 王晓川 任怡 谭郁松 《计算机工程与科学》 CSCD 北大核心 2024年第10期1711-1719,共9页
针对边缘函数计算服务FaaS中不同负载之间资源抢占导致的资源分配不公平、利用率不高的问题,提出一种时间感知的主导资源公平调度算法。首先,分析了现有主导资源公平调度算法在应用到边缘函数计算服务时的不足;其次,提出加入函数实例运... 针对边缘函数计算服务FaaS中不同负载之间资源抢占导致的资源分配不公平、利用率不高的问题,提出一种时间感知的主导资源公平调度算法。首先,分析了现有主导资源公平调度算法在应用到边缘函数计算服务时的不足;其次,提出加入函数实例运行时间权重,并通过时间感知队列和主导资源公平队列协同实现对函数运行所需要的资源进行公平分配和集群资源充分利用;最后,基于主流开源函数计算服务平台的调度器对算法进行了实现。采用公开负载运行数据集的测试结果表明,该算法最多提升了18.1%的CPU利用率和21.8%的内存利用率,并且执行时间最多降低了26.1%,能够有效提升边缘函数计算服务的资源分配公平性,且提高了资源利用率。 展开更多
关键词 边缘计算 函数计算服务 时间感知 主导资源公平调度
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CD4^(+)CD25^(+) regulatory T cells decreased future liver remnant after associating liver partition and portal vein ligation for staged hepatectomy 被引量:1
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作者 Wei Wang Chun-Hui Ye +7 位作者 Zhen-Feng Deng Ji-Long Wang ling Zhang li bao Bang-Hao Xu Hai Zhu Ya Guo Zhang Wen 《World Journal of Gastrointestinal Surgery》 2023年第5期917-930,共14页
BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)is an innovative surgical approach for the treatment of massive hepatocellular carcinoma(HCC),the key to successful planned ... BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)is an innovative surgical approach for the treatment of massive hepatocellular carcinoma(HCC),the key to successful planned stage 2 ALPPS is future liver remnant(FLR)volume growth,but the exact mechanism has not been elucidated.The correlation between regulatory T cells(Tregs)and postoperative FLR regeneration has not been reported.AIM To investigate the effect of CD4^(+)CD25^(+)Tregs on FLR regeneration after ALPPS.METHODS Clinical data and specimens were collected from 37 patients who developed massive HCC treated with ALPPS.Flow cytometry was performed to detect changes in the proportion of CD4^(+)CD25^(+)Tregs to CD4^(+)T cells in peripheral blood before and after ALPPS.To analyze the relationship between peripheral blood CD4^(+)CD25^(+)Treg proportion and clinicopathological information and liver volume.RESULTS The postoperative CD4^(+)CD25^(+)Treg proportion in stage 1 ALPPS was negatively correlated with the amount of proliferation volume,proliferation rate,and kinetic growth rate(KGR)of the FLR after stage 1 ALPPS.Patients with low Treg proportion had significantly higher KGR than those with high Treg proportion(P=0.006);patients with high Treg proportion had more severe postoperative pathological liver fibrosis than those with low Treg proportion(P=0.043).The area under the receiver operating characteristic curve between the percentage of Tregs and proliferation volume,proliferation rate,and KGR were all greater than 0.70.CONCLUSION CD4^(+)CD25^(+)Tregs in the peripheral blood of patients with massive HCC at stage 1 ALPPS were negatively correlated with indicators of FLR regeneration after stage 1 ALPPS and may influence the degree of fibrosis in patients’livers.Treg percentage was highly accurate in predicting the FLR regeneration after stage 1 ALPPS. 展开更多
关键词 Associating liver partition and portal vein ligation for staged hepatectomy Regulatory T cells Future liver remnant
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大承气汤联合穴位贴敷治疗急性胰腺炎
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作者 谭文君 邢斌瑜 +3 位作者 王赛宇 李豹 陈霖玉 王文静 《吉林中医药》 2024年第9期1060-1063,共4页
目的探讨大承气汤联合穴位贴敷治疗急性胰腺炎的临床疗效。方法选择2021年1月—2023年1月收治急性胰腺炎患者81例,按照随机数表法分为大承气汤组、穴位贴敷组、联合组(大承气汤联合穴位贴敷组),各27例。比较3组临床疗效、治疗前后中医... 目的探讨大承气汤联合穴位贴敷治疗急性胰腺炎的临床疗效。方法选择2021年1月—2023年1月收治急性胰腺炎患者81例,按照随机数表法分为大承气汤组、穴位贴敷组、联合组(大承气汤联合穴位贴敷组),各27例。比较3组临床疗效、治疗前后中医证候积分、实验室指标变化,比较3组不良反应发生情况。结果联合组临床疗效优于大承气汤组及穴位贴敷组(P<0.05);治疗后3组恶心呕吐、胃脘胀满、剧烈腹痛、口渴少饮评分下降(P<0.05),联合组低于大承气汤组与穴位贴敷组(P<0.05);治疗后3组血淀粉酶(AMS)、二胺氧化酶(DAO)、C反应蛋白(CRP)显著下降(P<0.05),联合组低于大承气汤组与穴位贴敷组(P<0.05);3组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论大承气汤联合穴位贴敷治疗急性胰腺炎疗效显著,可有效改善临床症状,增强胃肠道动力,促进胃肠功能恢复。 展开更多
关键词 大承气汤 穴位贴敷 急性胰腺炎 胃肠功能
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Vulvovaginal myeloid sarcoma with massive pelvic floor infiltration: A case report and review of literature
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作者 Jia-Xi Wang Heng Zhang +1 位作者 Gang Ning li bao 《World Journal of Clinical Cases》 SCIE 2022年第23期8312-8322,共11页
BACKGROUND Myeloid sarcoma(MS),including isolated and leukaemic MS,is an extramedullary myeloid tumour.MS can involve any anatomical site,but MS of the female genital tract is rare,with the ovaries and uterine body an... BACKGROUND Myeloid sarcoma(MS),including isolated and leukaemic MS,is an extramedullary myeloid tumour.MS can involve any anatomical site,but MS of the female genital tract is rare,with the ovaries and uterine body and cervix being the most commonly seen sites.Involvement of the vagina and vulva is extremely rare.CASE SUMMARY We report a rare case of MS with involvement of the vulva and vagina and massive infiltration of the pelvic floor.A 26-year-old woman presented with a vulvar mass,irregular vaginal bleeding and night sweats.Magnetic resonance imaging demonstrated an ill-defined,irregular vulvovaginal mass with massive involvement of the paravaginal tissue,urethra,posterior wall of the bladder,and pelvic floor.The signal and enhancement of the huge mass was homogeneous without haemorrhage or necrosis.Positron emission tomography/computed tomography showed high fluorodeoxyglucose uptake by the mass.Peripheral blood count detected blast cells.Vulvovaginal mass and bone marrow biopsies were performed,and immunohistochemistry confirmed the diagnosis of acute myeloid leukaemia(M-2 type,FAB classification)and vulvovaginal MS.The patient was treated with induction chemotherapy followed by allogeneic haematopoietic stem cell transplantation,and achieved complete remission.A systemic review of the literature on vulvovaginal MS was conducted to explore this rare entity’s clinical and radiological features.CONCLUSION Vulvovaginal MS is extremely rare.Diagnosis of vulvovaginal MS can only be confirmed histopathologically.Even though its clinical and imaging presentations are nonspecific,MS should be considered in the differential diagnosis of a newly developed T2-hyperintense,homogeneously enhanced vulvovaginal mass,especially in a patient with suspected haematological malignancy. 展开更多
关键词 Myeloid sarcoma VAGINA VULVA Acute myeloid lukaemia Imaging examination Case report
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Metabolomic profiling reveals hypoglycemic effect of Jinqi Jiangtang tablet on type 2 diabetic rats
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作者 Zheng-Yuan Shi li bao +3 位作者 Chun-Jing Yang Xi-Qiao Xu Dan Yan De-Chun Jiang 《Traditional Medicine Research》 2022年第3期105-112,共8页
Background:Si-Miao Sun wrote about the Jinqi Jiangtang tablet(JQJT)that is derived from the traditional Chinese herbal medicine Huanglian(Coptis Chinensis Franch)pills in the Essential Recipes for Emergent Use Worth A... Background:Si-Miao Sun wrote about the Jinqi Jiangtang tablet(JQJT)that is derived from the traditional Chinese herbal medicine Huanglian(Coptis Chinensis Franch)pills in the Essential Recipes for Emergent Use Worth A Thousand Gold in C.E.652.The tablet is used to treat diabetes in China owing to its powerful hypoglycemic properties.However,little is known about the metabolic mechanisms underlying these properties.Methods:Ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry-based metabolomics approach was performed to explore the metabolic mechanism of JQJT in the treatment of type 2 diabetes mellitus(T2DM).Results:The metabolomic pathway analysis and the Kyoto Encyclopedia of Genes and Genomes database were used to screen out 25 potential biomarkers and construct pertinent metabolic pathways.Five metabolites,such as allantoic acid and taurine,were downregulated and 20 metabolites were upregulated in the urine of T2DM rats.The biomarkers in the JQJT group exhibited a good callback trend.It is speculated that JQJT can alleviate T2DM by regulating the disorders of taurine,hypotaurine,phenylalanine,ascorbate,and aldarate metabolism,as well as pentose and glucuronate interconversions.Conclusion:This study will be meaningful in the clinical application of JQJT and will be valuable for further exploration of the metabolic mechanisms underlying its properties. 展开更多
关键词 Jinqi Jiangtang tablet type 2 diabetes mellitus metabolomics UPLC-QTOF-MS traditional Chinese medicine
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Effect of Soil Fertilizer Application on Soil Nutrient Migration and Tea Quality of Plateau-Puerh Tea
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作者 Hao Zhang Chunyu Dong +4 位作者 lingyu Meng lijuan Reng Jiaqi li Naiming Zhang li bao 《Journal of Geoscience and Environment Protection》 2022年第4期273-286,共14页
In order to solve the problem of chemical fertilizer application balance of Pu’er tea in Taiwan, the effects of different fertilization treatments on land nutrient migration and tea quality were explored, and the bas... In order to solve the problem of chemical fertilizer application balance of Pu’er tea in Taiwan, the effects of different fertilization treatments on land nutrient migration and tea quality were explored, and the basis for rational fertilization of tea gardens was provided. In this study, the effects of different fertilization treatments on tea quality indexes were studied by three different sets of fertilization treatments in tea gardens. Three sets of different fertilization treatments were set up in the experiment: conventional fertilization treatment (T1), slow-release fertilizer reduction by 20% (T2) and slow-release fertilizer reduction by 30% (T3), and the quality index of tea under different fertilization treatments, as well as the alkaline nitrogen, available phosphorus and total nitrogen and total phosphorus content in surface water of the soil were measured and analyzed. The results showed that: 1) compared with T1, the soil available phosphorus in T3 decreased by 23.5%, and the alkalinelyzed nitrogen increased by 20.5%;2) compared with T1, the total nitrogen and total phosphorus concentrations of surface water in the T2 and T3 treatments were at a low level compared with T1;compared with T1, T2 decreased by 71.4%, and T3 decreased by 68.6%;3) compared with T1, T3 was able to maintain the quality indicators of amino acids, tea polyphenols and soluble sugars in tea in a high and stable range. Therefore, under the condition of conventional fertilization and reduction, a 30% reduction in slow-release fertilizer is currently more suitable for the fertilization technology of Menghai County Tea Garden. 展开更多
关键词 Slow Release of Fertilizer Fertilization Mode Tea Quality Nutrient Migration Reduction of Efficiency
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Heavy Metal Characteristics and Comprehensive Quality Index Evaluation of Soil-Crop System in 11 Cities of Yunnan Province, China
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作者 Chunyu Dong Min Zhang +6 位作者 Hao Zhang Haichan Yang Jiaqi li Fumin Tan Xinxing Dong Naiming Zhang li bao 《Journal of Geoscience and Environment Protection》 2022年第4期257-272,共16页
Yunnan province in China is a high background area of soil heavy metals, and agricultural planting and industrial and mining activities are relatively frequent, which aggravate soil heavy metal pollution. However, at ... Yunnan province in China is a high background area of soil heavy metals, and agricultural planting and industrial and mining activities are relatively frequent, which aggravate soil heavy metal pollution. However, at present, there are few reports on the overall or large-scale soil-crop pollution and risk assessment of heavy metals in Yunnan Province. This study through 11 cities in Yunnan province of China farmland soil-crop systems of heavy metal lead, cadmium content, enrichment coefficient is analyzed, and using the method of potential ecological harm index, index of compressive quality to evaluate heavy metal pollution soil-crop system risk. Results showed that the average content of soil heavy metal Cd and Pb were 1.31 mg/kg, 64.17 mg/kg, which are higher than the background value of Yunnan province. The average contents of Pb and Cd in the edible parts of crops were 0.20 mg/kg, 0.08 mg/kg. The average content of heavy metals in crops in Diqing (Pb) and Nujiang (Cd) was 0.72 mg/kg and 0.148 mg/kg. The enrichment coefficients of heavy metals in edible parts of crops were the largest in Diqing (Pb) and Zhaotong (Cd). The average value of ecological risk index of Pb element in soil is 2.79, which indicates that the study area is in a slight ecological hazard, the average value of the ecological risk index of Cd in soil is 126.43. The average value of the comprehensive quality impact index (IICQ) is 4.27, which indicates that the study area is moderately polluted. In this study, the contents of heavy metals Cd and Pb in soils and crops in different administrative regions were determined, and the heavy metals Pb and Cd in soil-crop system of Yunnan province, China were evaluated, it is expected to have important scientific and theoretical significance for the safe use of cultivated land to export safe agricultural products and promote the sustainable development of agriculture in Yunnan Plateau. 展开更多
关键词 Index of Compressive Quality Heavy Metals Soil-Crop System
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油酸和Span80协同煤油对低阶煤的浮选强化及分子模拟计算 被引量:1
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作者 刘凯歌 李钰炳 +2 位作者 李志红 栗褒 高建川 《煤炭转化》 CAS CSCD 北大核心 2024年第2期12-21,共10页
低阶煤表面含有较多含氧基团,可浮性差,采用传统煤油捕收剂不仅药剂消耗大,而且分选效果差。复配捕收剂可以选择性地作用于矿物表面,从而提升浮选效果。以内蒙古色连二矿选煤厂低阶煤为研究对象,考察了传统捕收剂煤油的作用效果,并在此... 低阶煤表面含有较多含氧基团,可浮性差,采用传统煤油捕收剂不仅药剂消耗大,而且分选效果差。复配捕收剂可以选择性地作用于矿物表面,从而提升浮选效果。以内蒙古色连二矿选煤厂低阶煤为研究对象,考察了传统捕收剂煤油的作用效果,并在此基础上引入含氧有机药剂油酸和Span80与其复配,考察复配药剂对低阶煤浮选的强化作用,并对其作用机理进行分析。结果表明:煤油-油酸和煤油-Span80复配药剂对实验煤样浮选均有促进作用。捕收剂用量为4000 g/t,起泡剂用量为800 g/t时,煤油-Span80复配药剂对应的精煤产率为83.17%,精煤灰分为11.78%,尾煤灰分为69.15%,可燃体回收率达到93.48%,浮选完善指标为42.18%。与煤油和煤油-油酸复配药剂相比,煤油-Span80复配药剂可显著提升尾煤灰分和可燃体回收率,达到了较为理想的分选效果。机理研究结果显示,油酸和Span80与煤油复配,可显著降低药剂在矿浆中的分散粒径,提高其与颗粒的接触概率;同时,油酸和Span80与煤作用,掩蔽了煤样表面的亲水基团,改善了煤样疏水性,使其更易在煤粒表面铺展。模拟计算发现油酸和Span80药剂的前线轨道能隙小于正十二烷(煤油)的前线轨道能隙,煤油-油酸和煤油-Span80复配药剂与煤表面的相互作用能大于正十二烷(煤油)与煤表面的相互作用能,表明复配药剂更具活性,更容易与煤表面发生吸附。 展开更多
关键词 低阶煤 复配捕收剂 含氧官能团 浮选 分子模拟
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低阶煤表面润湿性调控对油类捕收剂铺展的影响 被引量:1
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作者 李世兴 栗褒 +2 位作者 车道昌 温全宝 刘生玉 《煤炭转化》 CAS CSCD 北大核心 2024年第1期1-9,共9页
为阐明浮选过程中低阶煤表面润湿性变化对油类捕收剂在煤表面铺展的影响,以哈尔乌素煤为研究对象,通过阳离子表面活性剂十二烷基三甲基溴化铵(DTAB)、阴离子表面活性剂十二烷基硫酸钠(SDS)和非离子表面活性剂脂肪醇聚氧乙烯醚(AEO-4)对... 为阐明浮选过程中低阶煤表面润湿性变化对油类捕收剂在煤表面铺展的影响,以哈尔乌素煤为研究对象,通过阳离子表面活性剂十二烷基三甲基溴化铵(DTAB)、阴离子表面活性剂十二烷基硫酸钠(SDS)和非离子表面活性剂脂肪醇聚氧乙烯醚(AEO-4)对煤表面进行润湿性调控,使用原子力显微镜(AFM)对低阶煤表面的非极性捕收剂(煤油)油膜厚度进行直接测量,并对作用机制进行了研究。结果表明:非极性捕收剂在低阶煤表面的铺展与其疏水程度密切相关,经SDS,AEO-4和DTAB处理后捕收剂在低阶煤表面油膜的厚度分别为17.86 nm,18.06 nm,19.85 nm,其中DTAB处理后能够形成具有稳定的有序层和过渡层的双层油膜结构,这表明DTAB更有利于强化非极性捕收剂在低阶煤表面的铺展;在研究范围内,非离子表面活性剂AEO-4质量分数由0.5%增加到2.0%时,低阶煤表面的油膜厚度由10.89 nm增加到19.85 nm,说明表面活性剂质量分数增加可以增强捕收剂分子与低阶煤表面之间的相互作用,同时精煤产率由68.96%提升至70.91%,可燃体回收率由83.92%提升至85.82%,提高了低阶煤浮选效果。 展开更多
关键词 润湿性 表面活性剂 原子力显微镜 浮选 非极性捕收剂
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基于联络线可行域分析的跨区通道传输能力评估方法
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作者 袁泉 马骞 +5 位作者 李豹 王子强 周鑫 张蔷 孙宇军 赖晓文 《电力自动化设备》 EI CSCD 北大核心 2024年第9期170-178,共9页
跨区通道传输能力是区域调度机构预编制和下达送受电计划的关键参考信息。综合考虑多个相关子区域电网在不同时段运行边界的共同影响,有助于增强通道能力评估的全面性。提出一种基于联络线可行域分析的跨区通道传输能力评估方法。考虑... 跨区通道传输能力是区域调度机构预编制和下达送受电计划的关键参考信息。综合考虑多个相关子区域电网在不同时段运行边界的共同影响,有助于增强通道能力评估的全面性。提出一种基于联络线可行域分析的跨区通道传输能力评估方法。考虑子区域的平衡、安全以及时段耦合等约束条件,计算各子区域电网在各时段的联络线可行域;利用不同子区域可行域的组合、提升-投影策略求得全网运行视角下关键送受电通道的可行域结果,并借助可行域顶点与极限传输功率的对应关系评估跨区通道的传输能力。基于两区域及三区域互联系统的运行场景进行算例分析,验证所提方法的有效性。 展开更多
关键词 联络线 可行域 跨区通道 传输能力 多面体投影 顶点搜索法
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计及背靠背柔直运行灵活性的机组组合建模优化方法
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作者 翟鹤峰 李豹 +4 位作者 马骞 王子强 刘春晓 周保荣 周鑫 《电网技术》 EI CSCD 北大核心 2024年第6期2660-2669,I0120,I0121,共12页
背靠背柔性直流(后文简称柔直)因其具有降低短路电流、实现潮流快速翻转等优势正逐步应用于实际电力系统问题中,然而,背靠背柔直嵌入的电力系统优化调度问题的研究仍旧十分有限。为充分挖掘背靠背柔直运行灵活性的特性,紧密结合实际工... 背靠背柔性直流(后文简称柔直)因其具有降低短路电流、实现潮流快速翻转等优势正逐步应用于实际电力系统问题中,然而,背靠背柔直嵌入的电力系统优化调度问题的研究仍旧十分有限。为充分挖掘背靠背柔直运行灵活性的特性,紧密结合实际工程背景需求,以电力系统典型的机组组合问题为例,提出了一种计及背靠背柔直运行灵活性的机组组合建模优化方法。首先,介绍了基于等值虚拟机建模思路的背靠背柔直优化模型,该模型考虑了背靠背柔直运行时功率调整的各项控制需求,包括功率调节方向、调节次数、功率翻转控制要求以及送电模式关联约束等,既避免了设备频繁动作可能带来的使用寿命缩短的问题,同时又保证了模型优化结果在现场的实际可执行性;其次,结合所构建的背靠背柔直模型提出了一种计及其灵活性的机组组合模型,并给出了该模型相应的转化求解方法。最后,通过对修改的IEEE 14节点、118节点系统的测试分析以及国内某实际电网的应用测试情况,验证了将所提柔直模型纳入机组组合问题进行联合优化的有效性,同时可以在保证系统运行安全性的前提下提升运行的经济性。 展开更多
关键词 背靠背柔直 机组组合 功率翻转 电力市场 等值虚拟机
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