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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke 被引量:4
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作者 Hongmei Duan Shulun Li +11 位作者 Peng Hao Fei Hao wen zhao Yudan Gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期409-415,共7页
Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactiv... Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke. 展开更多
关键词 adult endogenous neurogenesis ANGIOGENESIS basic fibroblast growth factor-chitosan gel CHITOSAN functional recovery ischemic stroke neural stem cell newborn neuron
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Establishment and evaluation of a prognostic model for patients with unresectable gastric cancer liver metastases 被引量:1
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作者 Zheng-Yao Chang wen-Xing Gao +3 位作者 Yue Zhang wen zhao Di Wu Lin Chen 《World Journal of Clinical Cases》 SCIE 2024年第13期2182-2193,共12页
BACKGROUND Liver metastases(LM)is the primary factor contributing to unfavorable outcomes in patients diagnosed with gastric cancer(GC).The objective of this study is to analyze significant prognostic risk factors for... BACKGROUND Liver metastases(LM)is the primary factor contributing to unfavorable outcomes in patients diagnosed with gastric cancer(GC).The objective of this study is to analyze significant prognostic risk factors for patients with GCLM and develop a reliable nomogram model that can accurately predict individualized prognosis,thereby enhancing the ability to evaluate patient outcomes.AIM To analyze prognostic risk factors for GCLM and develop a reliable nomogram model to accurately predict individualized prognosis,thereby enhancing patient outcome assessment.METHODS Retrospective analysis was conducted on clinical data pertaining to GCLM(type III),admitted to the Department of General Surgery across multiple centers of the Chinese PLA General Hospital from January 2010 to January 2018.The dataset was divided into a development cohort and validation cohort in a ratio of 2:1.In the development cohort,we utilized univariate and multivariate Cox regression analyses to identify independent risk factors associated with overall survival in GCLM patients.Subsequently,we established a prediction model based on these findings and evaluated its performance using receiver operator characteristic curve analysis,calibration curves,and clinical decision curves.A nomogram was created to visually represent the prediction model,which was then externally validated using the validation cohort.RESULTS A total of 372 patients were included in this study,comprising 248 individuals in the development cohort and 124 individuals in the validation cohort.Based on Cox analysis results,our final prediction model incorporated five independent risk factors including albumin levels,primary tumor size,presence of extrahepatic metastases,surgical treatment status,and chemotherapy administration.The 1-,3-,and 5-years Area Under the Curve values in the development cohort are 0.753,0.859,and 0.909,respectively;whereas in the validation cohort,they are observed to be 0.772,0.848,and 0.923.Furthermore,the calibration curves demonstrated excellent consistency between observed values and actual values.Finally,the decision curve analysis curve indicated substantial net clinical benefit.CONCLUSION Our study identified significant prognostic risk factors for GCLM and developed a reliable nomogram model,demonstrating promising predictive accuracy and potential clinical benefit in evaluating patient outcomes. 展开更多
关键词 Gastric cancer Liver metastases NOMOGRAM Prognostic model Survival analysis
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Microfluidic thermotaxic selection of highlymotile sperm and in vitro fertilization
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作者 Sihan Chen Jiemin Chen +8 位作者 Zihan Qin Jibo Wang Yuwen Wang Rong Liu wen zhao Ming Zhang Yuanzhen Zhang Mengcheng Luo Pu Chen 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期687-700,共14页
The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing in... The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia. 展开更多
关键词 Microfluidic device THERMOTAXIS Sperm sorting Assisted reproductive technology In vitro fertilization
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Robust fixed-time flight controller for a dual-system convertible UAV in the cruise mode
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作者 Lulu Chen Zhenbao Liu +2 位作者 Qingqing Dang wen zhao wenyu Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期53-66,共14页
This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle(UAV)in the presence of parameter uncertainties,unmodeled uncertainties and wind di... This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle(UAV)in the presence of parameter uncertainties,unmodeled uncertainties and wind disturbances.First,a fixed-time disturbance observer(FXDO)based on the bi-limit homogeneity theory is designed to estimate the lumped disturbance of the convertible UAV model.Then,a fixed-time integral sliding mode control(FXISMC)is combined with the FXDO to achieve strong robustness and chattering reduction.Bi-limit homogeneity theory and Lyapunov theory are applied to provide detailed proof of the fixed-time stability.Finally,numerical simulation experimental results verify the robustness of the proposed algorithm to model parameter uncertainties and wind disturbances.In addition,the proposed algorithm is deployed in a open-source UAV autopilot and its effectiveness is further demonstrated by hardware-in-the-loop experimental results. 展开更多
关键词 Convertible UAV Flight control Disturbance observer Fixed-time control
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基于振动台试验的水平层状边坡共振响应分析
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作者 文钊 刘汉香 +2 位作者 李欣 魏应松 王铭萱 《地震工程与工程振动》 CSCD 北大核心 2024年第3期116-126,共11页
共振现象已经多次在汶川震害调查中被发现,其在结构工程中已经得到了广泛的研究,但在边坡工程中尚未开展深入的研究。采用振动台模型试验开展水平层状边坡的固有振动特性及其共振响应研究。首先分别通过白噪声激振、正弦波扫频和天然波... 共振现象已经多次在汶川震害调查中被发现,其在结构工程中已经得到了广泛的研究,但在边坡工程中尚未开展深入的研究。采用振动台模型试验开展水平层状边坡的固有振动特性及其共振响应研究。首先分别通过白噪声激振、正弦波扫频和天然波激振获取边坡的固有频率,讨论不同方法在获取边坡固有频率方面的优劣性。其次,通过输入不同频率、不同幅值的正弦波激励,研究边坡的动力响应特征,重点关注边坡在共振频率处的加速度和位移响应特征。结果表明:白噪声激振和扫频试验分析结果较为接近,且白噪声激振对于边坡固有频率的变化识别更为敏感,天然波谱比曲线由于出现多个峰值,导致固有频率的确定较为模糊。边坡在其固有频率处存在共振响应现象,表现为边坡加速度峰值放大系数和位移响应峰值在共振频率段会出现峰值集聚,且相较于高程效应,共振对边坡响应的放大效应具有主导作用,会加剧边坡在振动作用下的变形破坏。研究有助于从边坡共振的角度揭示边坡的地震响应特征,也可以为边坡的抗减震研究提供思路。 展开更多
关键词 水平层状边坡 振动台试验 固有振动特性 共振响应
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The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis
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作者 Zhi-Chu Ma Rui Niu wen zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期140-150,共11页
In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)... In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing. 展开更多
关键词 gravitational waves-gravitation-black hole physics
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Two Cases of Autoimmune Encephalitis with Multiple Anti-neuronal Antibodies
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作者 Guomin Xie wen zhao Xiping Wu 《Journal of Clinical and Nursing Research》 2024年第8期15-20,共6页
Autoimmune encephalitis(AE)can arise from various etiologies and present with complex clinical manifestations,especially in cases involving multiple anti-neuronal antibodies.This report presents two cases of AE with m... Autoimmune encephalitis(AE)can arise from various etiologies and present with complex clinical manifestations,especially in cases involving multiple anti-neuronal antibodies.This report presents two cases of AE with multiple anti-neuronal antibodies admitted to Ningbo Medical Center Li Huili Hospital on October 9,2020,and March 12,2024.Case 1 is a 15-year-old boy with positive anti-N-methyl-D-aspartate receptor(NMDAR)and anti-metabotropic glutamate receptor 5(mGluR5)antibodies in his serum and cerebrospinal fluid(CSF).Case 2 is a 14-year-old boy with positive NMDAR and myelin oligodendrocyte glycoprotein(MOG)antibodies in his CSF.Patients with AE who have multiple anti-neuronal antibodies present significant diagnostic and therapeutic challenges,warranting close clinical attention. 展开更多
关键词 Autoimmune encephalitis Anti-neuronal antibody TREATMENT
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射频消融治疗包膜下与非包膜下早期肝细胞癌患者的远期预后
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作者 温钊 臧铁柱 +2 位作者 宋晓改 张炫 江艳丽 《河南医学研究》 CAS 2023年第15期2738-2744,共7页
目的基于倾向评分匹配(PSM)比较射频消融(RFA)对包膜下和非包膜下早期肝细胞癌(HCC)患者的长期疗效。方法选取2018年1月至2021年12月河南科技大学第二附属医院收治的接受超声引导下经皮RFA作为一线治疗的143名早期HCC患者为研究对象。... 目的基于倾向评分匹配(PSM)比较射频消融(RFA)对包膜下和非包膜下早期肝细胞癌(HCC)患者的长期疗效。方法选取2018年1月至2021年12月河南科技大学第二附属医院收治的接受超声引导下经皮RFA作为一线治疗的143名早期HCC患者为研究对象。将患者分为包膜下组和非包膜下组,使用PSM方法均衡两组间基线信息,评估包膜下位置与RFA治疗结果的相关性,计算并比较两组间局部肿瘤进展(LTP)、无病生存率(DFS)及总生存率(OS)。结果PSM后有47对基线均衡的患者入组。包膜下组1、2和3 a的DFS率分别为76%、67%和60%,非包膜下组分别为76%、72%和67%;包膜下组1、2和3 a的OS率分别为95%、92%和89%,非包膜下组分别为98%、95%和91%。邻近包膜下并不是影响DFS(HR=1.154,P=0.672)和OS(HR=0.815,P=0.718)的独立危险因素。此外,两组的LTP发生率、严重并发症率、技术成功率、术后住院时间比较差异无统计学意义(P>0.05)。结论RFA治疗包膜下组和非包膜下组HCC的LTP、DFS、OS和严重并发症发生率无显著差异。 展开更多
关键词 肝细胞癌 射频消融 倾向评分匹配 局部肿瘤进展 无病生存率 总生存率
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射频消融治疗邻近胃肠道肝细胞癌的长期疗效和安全性
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作者 温钊 臧铁柱 +2 位作者 姜卫波 张炫 江艳丽 《河南医学研究》 CAS 2023年第16期2917-2923,共7页
目的应用倾向评分匹配(PSM)比较射频消融(RFA)作为胃肠道旁和非胃肠道旁肝细胞癌(HCC)一线治疗的远期疗效和安全性。方法在河南科技大学第二附属医院2018年6月至2022年12月接受经皮超声引导下RFA治疗的189例HCC患者中,筛选并纳入143例HC... 目的应用倾向评分匹配(PSM)比较射频消融(RFA)作为胃肠道旁和非胃肠道旁肝细胞癌(HCC)一线治疗的远期疗效和安全性。方法在河南科技大学第二附属医院2018年6月至2022年12月接受经皮超声引导下RFA治疗的189例HCC患者中,筛选并纳入143例HCC患者。根据肿瘤位置将患者分为两组:胃肠道旁组(40例)和非胃肠道旁组(103例)。使用PSM均衡一般资料,降低偏倚和混杂因素对分析结果的影响。比较胃肠道组和非胃肠道组的无病生存(DFS)率及总生存(OS)率。采用Cox比例风险模型分析影响治疗结果的危险因素。结果PSM术后共配对37对患者。在PSM队列中,邻近胃肠道组和非邻近胃肠道组1、2、3 a DFS率分别为75%、60%、56%和71%、63%、63%(P=0.405);1、2、3 a OS率分别为97%、93%、89%和100%、100%、93%(P=0.953);邻近胃肠道不是DFS(P=0.411)及OS(P=0.954)的独立危险因素。两组在技术成功率、技术有效率、术后并发症/严重并发症、住院时间及局部肿瘤进展(LTP)方面差异无统计学意义(P>0.05)。结论邻近胃肠道旁和非邻近胃肠道旁HCC患者接受RFA治疗后的肿瘤局部进展率、远期疗效及并发症差异无统计学意义。 展开更多
关键词 射频消融 倾向评分匹配 胃肠道 无病生存率 总生存率
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基于熵权法和灰色关联度法评价丁香饮片质量 被引量:6
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作者 吴良发 赵雯 +1 位作者 刘敏 万林春 《药物流行病学杂志》 CAS 2023年第8期906-914,共9页
目的 基于熵权法与灰色关联度法进行丁香饮片质量多指标综合评价研究。方法 测定25批不同产地的丁香饮片样品中β-石竹烯、α-石竹烯、丁香酚、乙酸丁香酚酯和挥发性醚浸出物5个主要指标的含量,采用灰色关联度法,以熵权法所得权重作为... 目的 基于熵权法与灰色关联度法进行丁香饮片质量多指标综合评价研究。方法 测定25批不同产地的丁香饮片样品中β-石竹烯、α-石竹烯、丁香酚、乙酸丁香酚酯和挥发性醚浸出物5个主要指标的含量,采用灰色关联度法,以熵权法所得权重作为分辨系数,构建丁香饮片质量评价模型。结果 25批丁香饮片的乙酸丁香酚酯权重最大,提示含量可能需要增加更有标示性的成分;相对关联度值的范围为0.164~0.739,不同产地的丁香饮片质量存在一定差异,质量排名前3的样品为Q15、Q17、Q18,产地均为马达加斯加,表明该产地丁香饮片品质较优。结论 基于熵权法和灰色关联度法所建立的质量评价新模型可用于丁香饮片的质量评价,熵权法赋权提高了灰色关联度法的可靠性及丁香饮片质量评价的科学性。 展开更多
关键词 丁香饮片 熵权法 灰色关联度法 质量评价
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Tight sandstone gas accumulation mechanisms and sweet spot prediction, Triassic Xujiahe Formation, Sichuan Basin, China 被引量:1
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作者 Lin Jiang wen zhao +3 位作者 Dong-Mei Bo Feng Hong Yan-Jie Gong Jia-Qing Hao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3301-3310,共10页
The prediction of continental tight sandstone gas sweet spots is an obstacle during tight sandstone gas exploration. In this work, the classic physical fluid charging experimental equipment is improved, the combinatio... The prediction of continental tight sandstone gas sweet spots is an obstacle during tight sandstone gas exploration. In this work, the classic physical fluid charging experimental equipment is improved, the combination of the gas migration and accumulation process with the pore network numerical simulation method is investigated, and application of the permeability/porosity ratio is proposed to predict the gas saturation and sweet spots of continental formations. The results show that (1) as the charging pressure increases, the permeability of the reservoir increases because more narrow pore throats are displaced in the percolation process;and (2) based on pore network numerical simulation and theoretical analysis, the natural gas migration and accumulation mechanisms are revealed. The gas saturation of tight sandstone rock is controlled by the gas charging pressure and dynamic percolation characteristics. (3) The ratio of permeability/porosity and fluid charging pressure is proposed to predict the gas saturation of the formation. The ratio is verified in a pilot and proven to be applicable and practical. This work highlights the tight sandstone gas migration and accumulation mechanisms and narrows the gap among microscale physical experiments, numerical simulation research, and field applications. 展开更多
关键词 Tight sandstone gas Hydrocarbon migration and accumulation Physical experiment Numerical simulation
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Response of fungal communities to afforestation and its indication for forest restoration
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作者 Kaichuan Huang Zhenli Guo +6 位作者 wen zhao Changge Song Hao Wang Junning Li Reyila Mumin Yifei Sun Baokai Cui 《Forest Ecosystems》 SCIE CSCD 2023年第4期436-447,共12页
Soil fungi in forest ecosystems have great potential to enhance host plant growth and systemic ecological functions and services.Reforestation at Saihanba Mechanized Forest Farm,the world's largest artificial plan... Soil fungi in forest ecosystems have great potential to enhance host plant growth and systemic ecological functions and services.Reforestation at Saihanba Mechanized Forest Farm,the world's largest artificial plantation,has been integral to global forest ecosystem preservation since the 1950s.To better assess the ecological effects of soil microbiology after afforestation,fungal diversity and community structure(using Illumina sequencing)from forests dominated by Larix gmelinii var.principis-rupprechtii,Pinus sylvestris var.mongolica and Picea asperata,and from grassland were surveyed.In total,4,540 operational taxonomic units(OTUs)were identified,with Mortierella and Solicoccozyma being the dominant genera of grassland soil and Inocybe,Cortinarius,Piloderma,Tomentella,Sebacina,Hygrophorus and Saitozyma dominating the plantation soil.Principle coordinate analysis(PCoA)and co-occurrence networks revealed differences in fungal structure after afforestation.Significantly,more symbiotroph guilds were dominated by ectomycorrhizal fungi in plantations under the prediction of FUNGuild.The community composition and diversity of soil fungi were significantly influenced by pH via redundancy analysis(RDA)and the Mantel test(p<0.01).This finding emphasizes that soil pH has a strong effect on the transition of fungal communities and functional taxa from grassland to plantation,providing a novel indicator for forest restoration. 展开更多
关键词 Soil fungi Fungal diversity Community structure Function prediction Co-occurrence network
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海上风电机组齿轮箱进口油温异常预测
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作者 张宁 陶建权 +3 位作者 温钊 刘冰冰 周庆梅 胡号朋 《船舶工程》 CSCD 北大核心 2023年第S02期58-63,77,共7页
由于海上风电机组齿轮箱要长期承受无规律的变向变载荷的风力作用以及强阵风的冲击,为保证风电机组可靠运行,对齿轮箱进口油温进行异常预测。结合风电机组SCADA运行数据提出了一种基于SVM-RFECV算法和BP神经网络的风电机组齿轮箱进口油... 由于海上风电机组齿轮箱要长期承受无规律的变向变载荷的风力作用以及强阵风的冲击,为保证风电机组可靠运行,对齿轮箱进口油温进行异常预测。结合风电机组SCADA运行数据提出了一种基于SVM-RFECV算法和BP神经网络的风电机组齿轮箱进口油温异常预测方法。首先完成数据的预处理,然后利用SVM-RFECV算法计算不同变量的重要度,并选择平均交叉验证均方误差的最小变量组成最优特征,最后利用选取的最优特征数据建立的BP神经网络的预测模型,实现对风电机组齿轮箱进口油温异常预警。通过海上某风电场现场实际SCADA数据对模型进行验证,结果表明提出的方法能有效实现对风电机组齿轮箱进口油温异常预测。 展开更多
关键词 风电机组齿轮箱 组合算法 神经网络 异常预测
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助力火箭,推动梦想——神秘的助推剂
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作者 吴亚男 冉学成 +4 位作者 高娟娟 赵雯 王俊科 宗盈晓 陈建成 《大学化学》 CAS 2023年第12期181-185,共5页
生存在古丝绸之路上河西走廊的朱雀家族成立了蓝箭基地,一直在探索环保、经济和安全的助推剂。小朱雀来参观,了解了多种液体推进剂,有推力巨大但容易积碳的液氧煤油、环保但耗能的液氧液氢、稳定但有毒性的偏二甲肼和四氧化二氮,最后他... 生存在古丝绸之路上河西走廊的朱雀家族成立了蓝箭基地,一直在探索环保、经济和安全的助推剂。小朱雀来参观,了解了多种液体推进剂,有推力巨大但容易积碳的液氧煤油、环保但耗能的液氧液氢、稳定但有毒性的偏二甲肼和四氧化二氮,最后他们了解到由蓝箭基地发射的朱雀二号运载火箭是全球首枚以液氧甲烷为推进剂的火箭。甲烷有丰富的储量、温和的储存条件和运输安全性、燃烧充分而且产物无污染,在未来有更广阔的用途。 展开更多
关键词 助推剂 液氧甲烷 朱雀二号
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巧用“调查研究+共同缔造”破解街道基层治理难题——中国光谷创建“无癣街区”的“九峰试验”解析
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作者 李华芬 杨忠华 +1 位作者 金婵 温钊 《城市管理与科技》 2023年第6期23-25,29,共4页
武汉东湖新技术开发区(中国光谷)九峰街道兴调研、重实践,用共情管理践行“城市是我家”理念,不断探索城市治理新模式,目前在治理“牛皮癣”提升城市环境上取得阶段性成果,辖区面貌大为改善。在创建“无癣街区”的行动中,除了街道综合... 武汉东湖新技术开发区(中国光谷)九峰街道兴调研、重实践,用共情管理践行“城市是我家”理念,不断探索城市治理新模式,目前在治理“牛皮癣”提升城市环境上取得阶段性成果,辖区面貌大为改善。在创建“无癣街区”的行动中,除了街道综合行政执法中心,还有保洁公司“除癣队”、房产中介员工、施工方共同参与。今后,共治力量还将邀请管道疏通、家电维修、家政服务等公司加入。多方力量汇聚成“基层共治联盟”,着力解决街道在城市治理中遇到的各种疑难杂症。 展开更多
关键词 武汉东湖新技术开发区 房产中介 家政服务 阶段性成果 光谷 疑难杂症 综合行政执法 家电维修
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Cr3C2抑制剂含量对WC-8%Co-0.5%(VC/Cr3C2)超细硬质合金性能的影响 被引量:3
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作者 孙文文 栾道成 +6 位作者 包帅 陈杰 王楠 汪思敏 李京筱 文钊 王正云 《热加工工艺》 CSCD 北大核心 2018年第16期70-73,共4页
将Cr3C2晶粒长大抑制剂添加到WC-8%Co-0.5%(VC/Cr3C2)超细硬质合金中,通过对试样进行金相组织分析、SEM形貌观察、洛氏硬度(HRA)测试、三点抗弯强度测试和密度测量,研究了Cr3C2添加量对WC-8%Co-0.5%(VC/Cr3C2)超细硬质合金力学性... 将Cr3C2晶粒长大抑制剂添加到WC-8%Co-0.5%(VC/Cr3C2)超细硬质合金中,通过对试样进行金相组织分析、SEM形貌观察、洛氏硬度(HRA)测试、三点抗弯强度测试和密度测量,研究了Cr3C2添加量对WC-8%Co-0.5%(VC/Cr3C2)超细硬质合金力学性能及组织结构的影响。结果表明,不同Cr3C2加入量的WC-8%Co-0.5%(VC/Cr3C2)合金试样均拥有细小均匀的微观组织,其硬度随着Cr3C2添加量的增多而不断增加;抗弯强度则先增加后减小,当Cr3C2添加量为0.1%时,试样抗弯强度达到峰值2450 MPa;试样密度则在Cr3C2添加量增加到0.3%时出现降低。 展开更多
关键词 WC-CO 硬质合金 CR3C2 抑制剂
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动态硫化丁基橡胶/聚丙烯热塑性硫化胶的相态结构演变及阻尼性能 被引量:4
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作者 汤琦 郎秀瑞 +3 位作者 韩立静 赵文 王春芙 宗成中 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第11期93-100,共8页
通过动态硫化方法制备了丁基橡胶/聚丙烯热塑性硫化胶(IIR/PP-TPV),研究了动态硫化过程中交联度、橡塑两相相态结构和PP相晶体结构的演变,并用动态力学热分析方法测试了IIR/PP-TPV橡塑两相相容性和阻尼性能。结果表明,随着动态硫化时间... 通过动态硫化方法制备了丁基橡胶/聚丙烯热塑性硫化胶(IIR/PP-TPV),研究了动态硫化过程中交联度、橡塑两相相态结构和PP相晶体结构的演变,并用动态力学热分析方法测试了IIR/PP-TPV橡塑两相相容性和阻尼性能。结果表明,随着动态硫化时间的延长,体系的交联度逐渐增加,当动态硫化时间为90 s时,交联度趋于稳定,拉伸强度达到最大值,扭矩值先增加后减小。动态硫化过程中橡塑两相由双连续相演变为海岛相结构,IIR橡胶相交联颗粒粒径由10μm减小到2μm左右;PP相的晶体尺寸减小,分布变得均一,X射线衍射分析表明动态硫化过程不会改变PP相的晶型结构。相态演变过程中,IIR/PP-TPV由2个转变为1个tanδ峰值,橡塑两相相容性提高;随着动态硫化的进行,T_g向高温方向偏移,T_p值增大,阻尼温域变宽。循环回收4次后,拉伸强度和断裂伸长率保持率达88%和86%;IIR交联颗粒粒径变大,连续的PP相为IIR/PP-TPV提供了优异的可重复加工性能。 展开更多
关键词 动态硫化 丁基橡胶 聚丙烯 热塑性硫化胶 相态结构 阻尼性能
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叶酸和维生素B_(12)对产蛋鸡生产性能、小肠屏障功能及相关基因表达的影响 被引量:6
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作者 武笑天 温曌 +3 位作者 李锐瑞 白彦 王瑞 杨玉 《动物营养学报》 CAS CSCD 北大核心 2021年第5期2616-2630,共15页
本试验旨在研究饲粮中添加不同水平叶酸和维生素B_(12)对产蛋高峰期京红蛋鸡生产性能、蛋品质、小肠组织形态、小肠屏障功能及相关基因表达的影响。试验选用28周龄京红蛋鸡972只,随机分为9个组,每组6个重复,每个重复18只鸡。采用2因素3... 本试验旨在研究饲粮中添加不同水平叶酸和维生素B_(12)对产蛋高峰期京红蛋鸡生产性能、蛋品质、小肠组织形态、小肠屏障功能及相关基因表达的影响。试验选用28周龄京红蛋鸡972只,随机分为9个组,每组6个重复,每个重复18只鸡。采用2因素3水平试验设计,分别在基础饲粮中添加不同水平的叶酸和维生素B_(12),叶酸设0、2和5 mg/kg 3个添加水平,维生素B_(12)设0、25和75μg/kg 3个添加水平。试验预试期2周,正试期8周。结果表明:1)饲粮添加叶酸和维生素B_(12)及其互作效应对京红蛋鸡生产性能无显著影响(P>0.05)。2)饲粮添加2 mg/kg叶酸显著提高了蛋形指数、蛋壳厚度、蛋黄颜色和哈氏单位(P<0.05),添加25μg/kg维生素B_(12)显著提高了蛋壳厚度和哈氏单位(P<0.05);叶酸和维生素B_(12)互作效应显著提高了哈氏单位(P<0.05)。3)饲粮添加2 mg/kg叶酸显著提高了空肠和回肠绒毛高度和绒毛高度/隐窝深度(V/C)值(P<0.05),添加25μg/kg维生素B_(12)显著提高了十二指肠绒毛高度和V/C值(P<0.05);叶酸和维生素B_(12)互作效应对十二指肠和空肠绒毛高度和V/C值影响显著(P<0.05),2 mg/kg叶酸和25μg/kg维生素B_(12)添加组显著高于未添加组(P<0.05)。4)饲粮添加叶酸和维生素B_(12)及其互作效应对十二指肠和空肠闭锁蛋白(occludin)和黏蛋白2(MUC2)mRNA相对表达量影响显著(P<0.05),2 mg/kg叶酸和25μg/kg维生素B_(12)添加组显著高于未添加组(P<0.05)。5)饲粮添加2 mg/kg叶酸显著降低了十二指肠、空肠和回肠Toll样受体4(TLR4)、核转录因子-κB(NF-κB)、肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)mRNA相对表达量(P<0.05),显著提高了十二指肠、空肠和回肠白细胞介素-13(IL-13)mRNA相对表达量(P<0.05);添加25μg/kg维生素B_(12)显著降低了十二指肠、空肠和回肠TLR4和TNF-αmRNA相对表达量(P<0.05),显著提高了十二指肠、空肠和回肠白细胞介素-10(IL-10)mRNA相对表达量(P<0.05)。叶酸和维生素B_(12)互作效应对十二指肠和空肠TLR4、NF-κB、TNF-α、IL-1β和IL-10 mRNA相对表达量影响显著(P<0.05),2 mg/kg叶酸和25μg/kg维生素B_(12)添加组十二指肠和空肠TLR4、NF-κB、TNF-α和IL-1βmRNA相对表达量显著低于未添加组(P<0.05),十二指肠和空肠IL-10 mRNA相对表达量显著高于未添加组(P<0.05)。综上所述,饲粮添加适宜水平的叶酸和维生素B_(12)能够提高产蛋高峰期京红蛋鸡鸡蛋哈氏单位,改善小肠组织形态,改善小肠屏障功能及炎症相关基因的表达,以饲粮(含1.35 mg/kg叶酸和25μg/kg维生素B_(12))中添加2 mg/kg叶酸和25μg/kg维生素B_(12)效果较好。 展开更多
关键词 叶酸 维生素B_(12) 蛋鸡 生产性能 肠道形态 肠道屏障功能
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叶酸对产蛋鸡血液免疫指标和肠道屏障功能的影响 被引量:4
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作者 武笑天 温曌 +3 位作者 李锐瑞 白彦 王瑞 杨玉 《中国畜牧杂志》 CAS 北大核心 2021年第8期174-181,共8页
本试验旨在研究饲粮中添加不同水平的叶酸对产蛋高峰期京红蛋鸡血液指标、肠道组织形态及肠道屏障相关基因表达的影响。选用30周龄京红蛋鸡648只,随机分为6个处理,每个处理6个重复,每个重复18只鸡。对照组饲喂基础日粮(叶酸含量为0.35 m... 本试验旨在研究饲粮中添加不同水平的叶酸对产蛋高峰期京红蛋鸡血液指标、肠道组织形态及肠道屏障相关基因表达的影响。选用30周龄京红蛋鸡648只,随机分为6个处理,每个处理6个重复,每个重复18只鸡。对照组饲喂基础日粮(叶酸含量为0.35 mg/kg),试验组分别在基础日粮中添加1、3、6、12、24 mg/kg叶酸。预试期2周,正试期6周。结果表明:与对照组相比,饲粮中添加6 mg/kg和12 mg/kg叶酸提高了血清免疫球蛋白A(IgA)和血清免疫球蛋白M(IgM)抗体合成水平(P<0.05),降低血清中内毒素(ET)含量及二胺氧化酶(DAO)活性(P<0.05);与对照组相比,饲粮中添加6 mg/kg叶酸提高了十二指肠和空肠绒毛高度、空肠绒隐比(P<0.05);添加6 mg/kg和12 mg/kg叶酸增加了十二指肠、空肠和回肠闭锁蛋白(Occludin)、闭合小环蛋白-1(ZO-1)、黏蛋白2(MUC2)mRNA表达量(P<0.05);与对照组相比,饲粮中添加6 mg/kg和12 mg/kg叶酸降低了十二指肠TOLL样受体4(TLR4)、核转录因子-κB(NF-κB)、肿瘤坏死因子-α(TNF-α)、回肠TLR4、TNF-αmRNA表达量(P<0.05),增加了十二指肠分泌型免疫球蛋白A(SIgA)、白细胞介素-10(IL-10)和白细胞介素-13(IL-13)、回肠IL-13 mRNA表达量(P<0.05);添加3 mg/kg和6 mg/kg叶酸降低了空肠TLR4、NF-κB、白细胞介素-1β(IL-1β)mRNA表达量(P<0.05),增加了IL-10 mRNA表达量(P<0.05)。综上所述,添加适宜水平的叶酸能够提高京红蛋鸡血清免疫指标,改善肠道组织形态,综合改善了肠道屏障功能,以饲粮中添加6 mg/kg叶酸效果较好。 展开更多
关键词 叶酸 蛋鸡 血清免疫指标 肠道形态 肠道屏障功能
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益生木质纤维素对鸡盲肠黏膜免疫屏障的影响 被引量:4
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作者 温曌 武笑天 杨玉 《山西农业科学》 2021年第5期668-674,共7页
试验选用9周龄体质量相近的健康边鸡和伊莎褐鸡各108只笼养,采用2因素3水平试验设计,育成期自行配制益生木质纤维素含量不同、等能等蛋白的饲料,益生木质纤维素设2个水平(2%和4%),研究益生木质纤维素对不同品种鸡盲肠黏膜免疫屏障的影... 试验选用9周龄体质量相近的健康边鸡和伊莎褐鸡各108只笼养,采用2因素3水平试验设计,育成期自行配制益生木质纤维素含量不同、等能等蛋白的饲料,益生木质纤维素设2个水平(2%和4%),研究益生木质纤维素对不同品种鸡盲肠黏膜免疫屏障的影响。结果表明,20周边鸡胸腺免疫器官指数极显著高于伊莎褐鸡,且边鸡促炎性细胞因子TNF-α、IL-6 mRNA表达水平有低于伊莎褐鸡的趋势。添加益生木质纤维素对20周盲肠绒毛高度和绒隐比无显著影响,但对隐窝深度、黏液层厚度、IL-1、TNF-α、IL-10、IL-6、MUC2 mRNA表达有显著影响,且2%益生木质纤维素处理组极显著增加了盲肠黏液层厚度以及IL-10、MUC2 mRNA表达,极显著降低了盲肠隐窝深度和TNF-αmRNA表达,显著降低了盲肠IL-1、IL-6 mRNA表达;品种与益生木质纤维素互作对20周盲肠黏液层厚度以及TNF-α、MUC2 mRNA表达有显著影响。添加低纤维组(2%益生木质纤维素)可改善伊莎褐鸡和边鸡盲肠黏膜免疫屏障。 展开更多
关键词 益生木质纤维素 盲肠黏膜免疫屏障 肠道形态 细胞因子
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