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Novel methodology for casting process optimization using Gaussian process regression and genetic algorithm

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China Foundry 2009年第3期6卷 232-240页

作者： Yao Weixiong yang Yi zeng Bin School of Manufacturing Sci. and Eng. Sichuan UniversityChengdu 610065China School of Manufacturing Sci. and Eng.Sichuan UniversityChengdu 610065China School of Manufacturing Sci. and Eng.Sichuan UniversityChengdu 610065China

High pressure die casting (HPDC) is a versatile material processing method for mass-production of metal parts with complex geometries,and this method has been widely used in manufacturing various products of excellent dimensional accuracy and productivity. In order to ensure the quality of the components,a number of variables need to be properly set. A novel methodology for high pressure die casting process optimization was developed,validated and applied to selection of optimal parameters,which incorporate design of experiment (DOE),Gaussian process (GP) regression technique and genetic algorithms (GA). This new approach was applied to process optimization for cast magnesium alloy notebook shell. After being trained,using data generated by PROCAST (FEM-based simulation software),the GP model approximated well with the simulation by extracting useful information from the simulation results. With the help of MATLAB,the GP/GA based approach has achieved the optimum solution of die casting process condition settings.

关键词： high pressure die casting process optimization numerical simulation Gaussian process genetic algorithm

Effect of CD4^+CD25^+ regulatory T cells in the development of anterior chamber-associated immune deviation

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International Journal of Ophthalmology(English edition) 2011年第1期4卷 19-25页

作者： Shu-Xing Ji, Pei-zeng yang Department of Ophthalmology Daping Hospital Third Military Medical University Chongqing 400042 China Uveitis Study Center Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 Guangdong Province China National Ophthalmic Research Laboratory Guangzhou 510060 Guangdong Province China

AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)D25(+) T cells, CD4(+)D25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells from spleens of mice with ACAID were analyzed by flow cytometry. Foxp3 mRNA expression in purified CD4(+)CD25(+) T cells was analyzed using real-time PCR. The suppressive effect of purified CD4(+)CD25(+) T cells on the proliferation of CD4(+)CD25(-) T cells was evaluated by [H-3] thymidine incorporation. A blocking experiment was performed to further address the role of CD4(+)CD25(+) T cells in ACAID. The expression of IL-10 in purified CD4(+)CD25(+) T cells was evaluated by ELISA. RESULTS: Increased frequencies of CD4(+)CD25(+) T cells, CD4(+)CD25(+) Foxp3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells were observed in ACAID. The CD4(+)CD25(+) T cells from mice with ACAID showed enhanced suppressive effect on the proliferation of CD4(+)CD25(-) T cells. Treatment of BALB/c mice with anti-CD25 antibody after injection of OVA into the anterior chamber significantly inhibited the induction of ACAID. Furthermore, purified CD4(+)CD25(+) T cells from ACAID mice secreted IL-10. CONCLUSION: Our results demonstrate that Treg cells are induced in the mice undergoing ACAID. These Treg cells may play a role in the development of ACAID.

关键词： CD4+CD25+ regulatory T cells Foxp3 ACAID IL-10 PD-1

Relationship between bacteria and phytoplankton during the giant jellyfish Nemopilema nomurai bloom in an oligotrophic temperate marine ecosystem

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Acta Oceanologica Sinica 2016年第10期35卷 107-113页

作者： zeng yang HUANG Xuguang HUANG Bangqin MI Tiezhu Key Laboratory of Coastal and Wetland Ecosystems of Ministry of Education Xiamen University Fujian Provincial Key Laboratory of Coastal Ecology and Environmental Studies Xiamen University College of Chemistry and Chemical Engineering Ocean University of China

Bacterial abundance, phytoplankton community structure and environmental parameters were investigated to study the relationships between bacteria and phytoplankton during giant jellyfish Nemopilema nomurai blooms in the central Yellow Sea during 2013. N. nomurai appeared in June, increased in August, reached a peak and began to degrade in September 2013. Results showed that phosphate was possible a key nutrient for both phytoplankton and bacteria in June, but it changed to nitrate in August and September. Phytoplankton composition significantly changed that pico-phytoplankton relative biomass significantly increased, whereas other size phytoplankton significantly decreased during jellyfish bloom. In June, a significantly positive correlation was observed between chlorophyll a concentration and bacterial abundance（r=0.67, P0.001, n=34）.During jellyfish outbreak in August, there was no significant correlation between phytoplankton and bacteria（r=0.11, P0.05, n=25）, but the relationship（r=0.71, P0.001, n=31） was rebuilt with jellyfish degradation in September. In August, small size phytoplankton occupied the mixed layer in offshore stations, while bacteria almost distributed evenly in vertical. Chlorophyll a concentration significantly increased from（0.42±0.056） μg/L in June to（0.74±0.174） μg/L in August, while bacterial abundance just slightly increased. Additionally, the negative net community production indicated that community respiration was not entirely determined by the local primary productivity in August. These results indicated that jellyfish blooms potentially affect coupling of phytoplankton and bacteria in marine ecosystems.

关键词： jellyfish bloom Nemopilema nomurai phytoplankton pigments jellyfish DOM ecological consequence

基于多源探测数据的液态降水现象及量级综合判识研究

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气象水文海洋仪器 2024年第4期41卷 29-32,36页

作者：曾杨赖晨张娟娟江西省气象探测中心南昌330096 湖北省气象信息与技术保障中心武汉430074 江西省气候中心南昌330096

文章针对液态降水现象进行分析,利用自动气象站、双偏振天气雷达等设备观测资料,采用XGBoost、GBDT等机器学习算法,开展探测数据与降水量级的相关性分析,建立基于多源数据的降水类型及量级判识模型,实现对无雨、小雨、中雨、大雨、暴雨... 详细信息

文章针对液态降水现象进行分析,利用自动气象站、双偏振天气雷达等设备观测资料,采用XGBoost、GBDT等机器学习算法,开展探测数据与降水量级的相关性分析,建立基于多源数据的降水类型及量级判识模型,实现对无雨、小雨、中雨、大雨、暴雨五类降水类型的识别,最终生成判识格点产品,使降水类型判识空间分辨力得到一定程度的提升。

关键词：机器学习判识降水现象

Differentiation of human umbilical cord blood stem cells into hepatocytes in vivo and in vitro

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World Journal of Gastroenterology 2006年第25期12卷 4014-4019页

作者： Xiao-Peng Tang Min Zhang Xu yang Li-Min Chen yang zeng Research Center of Liver Diseases the Second Xiangya Hospital Central South University Changsha 410011 Hunan Province China

AIM： To study the condition and potentiality of human umbilical cord blood stem cells （HUCBSC） to differentiate into hepatocytes in vivo or in vitro. METHODS： In a cell culture study of human umbilical cord blood stem cell （HUCBSC） differentiation, human umbilical cord blood mononuclear cells （HUCBMNC） were separated by density gradient centrifugation. Fibroblast growth factor （FGF） and hepatocyte growth factor （HGF） and the supernatant of fetal liver were added in the inducing groups. Only FGF was added in the control group. The expansion and differentiation of HUCBMNC in each group were observed. Human alpha fetoprotein （AFP） and albumin （ALB） were detected by immunohistochemistry. In the animal experiments, the survival SD rats with acute hepatic injury after carbon tetrachloride （CCL4） injection 48 h were randomly divided into three groups. The rats in group A were treated with human umbilical cord blood serum. The rats in group B were treated with HUCBMNC transplantation. The rats in group C were treated with HUCBMNC transplantation followed by intraperitoneal cyclophosphamide for 7 d. The rats were killed at different time points after the treatment and the liver tissue was histopathologically studied and human AFP and ALB detected by immunohistochemistry. The human X inactive-specific transcript gene fragment in the liver tissue was amplified by PCR to find human DNA. RESULTS： The results of cell culture showed that adherent cells were stained negative for AFP or ALB in control group. However, the adherent cells in the inducing groups stained positive for AFP or ALB. The result of animal experiment showed that no human AFP or ALB positive cells present in the liver tissue of group A （control group）. However, many human AFP or ALB positive cells were scattered around sinus hepaUcus and the central veins of hepatic Iobules and in the portal area in group B and group C after one month. The fragment of human X chromagene could be detected in the liver tissue

关键词： Umbilical cord blood Stem cell Liver failure Cell transplantation Cell differentiation

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多糖基可降解膜的疏水性质强化研究进展

武汉工程大学学报 2024年第1期46卷 55-60页

作者：曾洋李欣吴考肖满姜发堂湖北工业大学生物工程与食品学院湖北武汉430068

多糖基可降解膜因具备无毒、环境友好、力学强度较好等特点,是替换传统石油基塑料膜的潜在选择。但大多数多糖的亲水性较强,使其形成的薄膜耐水性较弱,不利于实际应用。展示了近年来多糖基可降解复合膜疏水性质强化的研究进展。基于多... 详细信息

多糖基可降解膜因具备无毒、环境友好、力学强度较好等特点,是替换传统石油基塑料膜的潜在选择。但大多数多糖的亲水性较强,使其形成的薄膜耐水性较弱,不利于实际应用。展示了近年来多糖基可降解复合膜疏水性质强化的研究进展。基于多糖化学改性方法,介绍了常见多糖膜的疏水改性效果,包括改性淀粉膜、改性魔芋葡甘聚糖膜和改性壳聚糖膜;从物理共混的角度总结了多糖与其他天然成分复合成膜的疏水增强机理;从多层复合的角度说明了层层自组装、静电纺丝等离子体等技术对多糖基复合膜疏水效果的提升效果。建议今后从改性膜的分子组装结构及其组装过程等方面阐明改性膜的疏水结构形成机理,为其稳定生产提供理论指导。同时,探究结合多种成膜技术同步强化多糖基可降解膜的疏水和力学性能的可行性,提升多糖基可降解膜在包装上的应用效果与体验。

关键词：多糖可降解复合膜疏水强化

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电商直播背景下海南香蕉品牌营销策略研究

海南开放大学学报 2024年第2期25卷 68-74页

作者：潘友仙曾阳柳王芳海南大学国际商学院海南海口570228

随着互联网经济高速发展而诞生的“电商直播”无疑为农产品的推广销售与品牌建设带来了诸多机遇,但同时也带来了挑战。海南香蕉如何站在“电商直播”的经济新风口中,借助电商直播提高销量、扩大知名度,实现品牌化发展是值得深思的。通... 详细信息

随着互联网经济高速发展而诞生的“电商直播”无疑为农产品的推广销售与品牌建设带来了诸多机遇,但同时也带来了挑战。海南香蕉如何站在“电商直播”的经济新风口中,借助电商直播提高销量、扩大知名度,实现品牌化发展是值得深思的。通过对当前电商直播背景下海南香蕉品牌营销的现状及问题进行分析,提出相应的优化策略,促进海南香蕉品牌的发展与提升。

关键词：电商直播海南香蕉品牌营销品牌意识自由贸易港建设

结肠癌根治术后严重并发症危险因素分析及动态列线图预测模型构建

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解放军医学杂志 2024年第4期49卷 416-425页

作者：史益凡沈晓明杨增辉夏李许炳华鲍传庆江南大学附属医院胃肠外科江苏无锡214122

目的探讨结肠癌根治术后综合并发症指数(CCI)≥26.2分的独立危险因素,以此建立动态网页列线图预测模型并进行验证。方法回顾性收集2020年11月-2022年4月于江南大学附属医院接受根治性手术的结肠癌患者的临床资料,基于入院时间分为主要队... 详细信息

目的探讨结肠癌根治术后综合并发症指数(CCI)≥26.2分的独立危险因素,以此建立动态网页列线图预测模型并进行验证。方法回顾性收集2020年11月-2022年4月于江南大学附属医院接受根治性手术的结肠癌患者的临床资料,基于入院时间分为主要队列(2020年11月-2021年10月,n=438)与验证队列(2021年11月-2022年4月,n=196)。根据CCI计算器(http://***)得出所有患者的CCI评分,采用单因素和多因素logistic回归分析结肠癌患者术后CCI≥26.2的危险因素,并构建列线图模型。采用受试者工作特征(ROC)曲线、C指数及校准曲线评估列线图模型的区分度和一致性,决策曲线分析评估模型的临床获益,并对模型进行内部验证。结果主要队列438例患者中,63例(14.4%)术后CCI≥26.2分。多因素logistic回归分析显示,年龄≥60岁(OR=2.662,95%CI 1.341~5.285,P=0.005)、低第3腰椎旁骨骼肌指数(L3MI)(OR=4.572,95%CI 2.435~8.583,P<0.001)、NRS2002评分≥3分(OR=4.281,95%CI 2.304~7.952,P<0.001)和术前伴有肠梗阻(OR=3.785,95%CI 1.971~7.268,P<0.001)是结肠癌患者术后CCI≥26.2分的独立危险因素。据此建立静态及网页版动态列线图预测模型(https://***/DynNomCCI/)。列线图模型的C指数和曲线下面积(AUC)分别为0.742和0.787;校准曲线显示模型的预测概率与实际概率具有较好的一致性;内部验证显示模型具有良好的区分度(C指数=0.722,AUC=0.795)和预测一致性;决策曲线分析显示该预测模型具有临床获益和应用价值。结论基于4个独立危险因素构建的动态列线图模型能够便捷、可靠地预测结肠癌术后CCI≥26.2分的概率,有助于优化术前评估体系,制定精准的个体化诊疗方案,促进患者快速康复。

关键词：结肠癌综合并发症指数骨骼肌指数列线图模型

Scaled radar cross section measurement method for lossy targets via dynamically matching reflection coefficients in THz band

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Chinese Physics B 2022年第6期31卷 759-764页

作者： Shuang Pang yang zeng Qi yang Bin Deng Hong-Qiang Wang College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China

In the terahertz band,the dispersive characteristic of dielectric material is one of the major problems in the scaled radar cross section(RCS)measurement,which is inconsistent with the electrodynamics similitude deducted according to the Maxwell’s *** on the high-frequency estimation method of physical optics(PO),a scaled RCS measurement method for lossy objects is proposed through dynamically matching the reflection coefficients according to the distribution of the object *** of the model of SLICY are conducted,and the inversed RCS of the lossy prototype is obtained using the proposed *** the inversed RCS with the calculated results,the validity of the proposed method is *** proposed method provides an effective solution to the scaled RCS measurement for lossy objects in the THz band.

关键词： scaled measurement method radar cross section lossy targets terahertz