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基于高通量测序分析毛菊苣醇提物对db/db小鼠肠道菌群的影响
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作者 康金森 闫俊林 +5 位作者 张芮 仲烨伟 谭惠文 阿达来提·阿布都热西提 仝凤莲 马晓丽 《现代食品科技》 CAS 北大核心 2024年第5期1-7,共7页
该文探究毛菊苣醇提物对糖尿病小鼠(db/db小鼠)肠道菌群的影响。该研究以m/m小鼠为正常对照组(CON组),db/db小鼠随机分为模型组(MOD组)、二甲双胍组(MET组)、毛菊苣醇提物低剂量组(CGL组)、毛菊苣醇提物高剂量组(CGH组)。灌胃给药8周,... 该文探究毛菊苣醇提物对糖尿病小鼠(db/db小鼠)肠道菌群的影响。该研究以m/m小鼠为正常对照组(CON组),db/db小鼠随机分为模型组(MOD组)、二甲双胍组(MET组)、毛菊苣醇提物低剂量组(CGL组)、毛菊苣醇提物高剂量组(CGH组)。灌胃给药8周,对小鼠体质量、空腹血糖、肝脏总胆固醇(TC)、甘油三酯(TG)进行分析,对小鼠粪便进行16S rRNA测序分析,探究毛菊苣醇提物对小鼠肠道菌群的影响。毛菊苣醇提物高剂量组可调节db/db小鼠体质量及血糖,显著降低db/db小鼠TC、TG水平(P<0.05);测序结果显示CON组、MOD组、CGH组三组小鼠肠道菌群情况存在差异,毛菊苣醇提物给药可改善db/db小鼠的肠道菌群失调,上调db/db小鼠肠道菌群中有益菌双歧杆菌属(Bifidobacterium)、Romboutsia、普雷沃氏菌属(Prevotella)菌群相对丰度。研究证明了毛菊苣醇提物给药能调节db/db小鼠肠道菌群,通过提高有益菌相对丰度调节糖脂代谢,可为新疆地产毛菊苣药材资源的开发利用提供全新的研究思路。 展开更多
关键词 毛菊苣 2型糖尿病 db/db小鼠 肠道菌群 高通量测序
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基于304dB的北欧海相黏土参数空间非均匀变异性研究
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作者 陈朝晖 牛萌萌 +2 位作者 罗琳 黄凯华 唐冲 《岩土力学》 EI CAS CSCD 北大核心 2024年第2期525-538,共14页
由于应力和沉积作用的历史差异,不同场地的岩土类型与性质会有所不同;即使同一场地,在不同位置处的岩土类型及性质亦存在差异。目前普遍采用的均匀随机场模型很难准确表征上述复杂空间变异性,且缺乏原位测试数据的验证。为此,基于国际... 由于应力和沉积作用的历史差异,不同场地的岩土类型与性质会有所不同;即使同一场地,在不同位置处的岩土类型及性质亦存在差异。目前普遍采用的均匀随机场模型很难准确表征上述复杂空间变异性,且缺乏原位测试数据的验证。为此,基于国际土力学与岩土工程学会风险评估和管理委员会TC-304所开发和维护的岩土实测参数数据库304dB,对北欧三国挪威、芬兰、瑞典海相黏土参数的空间变异性展开了深入研究。分析比较了北欧三国海相黏土的统计特征参数沿深度变化的异同以及各参数相互影响的物理机制,明确了各参数的空间变异性规律。通过趋势性、涨落性与相关性分析,揭示了北欧三国海相黏土参数均值、标准差以及涨落尺度沿深度均非常数,均值沿深度线性增长,标准差沿深度的变化趋势近似为二次函数,相关函数与间距及位置有关,但随间距增长不会一致收敛。基于综合样本的分层相关性分析,建立了海相黏土参数分层非均匀随机场,该随机场均值为沿深度的线性函数,标准差为在空间变化的随机场,其趋势函数为沿深度的二次函数,不同分层位置处黏土参数可具有不同的均值和标准差初值,各层内参数具有不同涨落尺度。与均匀随机场以及仅考虑均值沿深度线性增长的非均匀场模型相比,所建立的分层非均匀随机场模型可以全面描述海相黏土参数均值、标准差及其相关性沿深度的复杂空间变异性及其非连续变化的分层特性。 展开更多
关键词 海相黏土 非均匀随机场 趋势分量 涨落分量 分层特性 数据库304db
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肉苁蓉不同提取部位对db/db小黑鼠降血糖作用 被引量:2
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作者 程世赞 廉婧 +4 位作者 聂紫璇 苏国明 常源 史辑 贾天柱 《药学研究》 CAS 2024年第1期6-14,共9页
目的探讨肉苁蓉和酒苁蓉不同提取部位对db/db小黑鼠降血糖的作用及机制。方法富集肉苁蓉和酒苁蓉总多糖、总寡糖和总苷部分,对其含量进行了比较分析。选用db/db小黑鼠为实验动物,给药28 d后,记录小黑鼠体重、进食量、饮水量,检测血糖,采... 目的探讨肉苁蓉和酒苁蓉不同提取部位对db/db小黑鼠降血糖的作用及机制。方法富集肉苁蓉和酒苁蓉总多糖、总寡糖和总苷部分,对其含量进行了比较分析。选用db/db小黑鼠为实验动物,给药28 d后,记录小黑鼠体重、进食量、饮水量,检测血糖,采用ELISA检测血清胰岛素(INS)、糖化血红蛋白(HbA1c),肝脏甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL-C)、高密度脂蛋白(HDL-C)、丙二醛(MDA)、超氧化物歧化酶(SOD),血浆和尿液中尿酸(UA)、肌酐(Cr)以及尿微量白蛋白(mALB)水平;HE染色方法制备胰腺和肾脏组织病理切片;IHC测定肾脏type-Ⅳ collagen蛋白表达水平。结果肉苁蓉多糖部位经过酒蒸后含量下降,肉苁蓉寡糖部位中的甜菜碱经过酒蒸后含量增加,总苷类成分酒蒸后松果菊苷的含量稍有下降,毛蕊花糖苷含量下降,异类叶升麻苷含量上升。与模型组相比,肉苁蓉和酒苁蓉不同提取部位能降低体重、空腹血糖(FBG)、口服葡萄糖耐量(OGTT)、HbA1c、胰岛素抵抗指数(HOMA-IR)、胰岛β细胞分泌指数(HOMA-β)、MDA、LDL-C、UA、Cr以及mALB,INS和HDL-C有上升趋势(P<0.05,P<0.01),且能改善胰腺和肾脏的病理损伤以及type-Ⅳ collagen的表达。结论肉苁蓉和酒苁蓉总苷组降血糖作用较好,酒苁蓉多糖和寡糖也有一定的降血糖作用。 展开更多
关键词 肉苁蓉 总多糖 总寡糖 总苷 db/db小黑鼠 降血糖
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有氧运动调节转化生长因子β/Smad通路缓解db/db糖尿病小鼠的肝脏纤维化
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作者 黄朝露 黄毅 +2 位作者 吴昌燕 李芳菲 李海燕 《中国组织工程研究》 CAS 北大核心 2025年第14期2951-2957,共7页
背景:有氧运动可抑制糖尿病小鼠肝纤维化,但具体作用机制尚未阐明。目的:基于转化生长因子β/Smad信号通路探讨有氧运动改善db/db小鼠肝纤维化的作用机制。方法:将8周龄雄性db/db小鼠和年龄匹配的m/m小鼠随机分为m/m对照组、m/m+运动组... 背景:有氧运动可抑制糖尿病小鼠肝纤维化,但具体作用机制尚未阐明。目的:基于转化生长因子β/Smad信号通路探讨有氧运动改善db/db小鼠肝纤维化的作用机制。方法:将8周龄雄性db/db小鼠和年龄匹配的m/m小鼠随机分为m/m对照组、m/m+运动组、db/db对照组、db/db+运动组,每组10只,运动组小鼠接受12周有氧运动。运动结束后检测各组小鼠空腹血糖,进行葡萄糖耐量测试和胰岛素耐量测试;摘取肝脏计算肝脏指数,摘眼球取血检测生化指标;苏木精-伊红染色、油红O染色和Masson染色观察小鼠肝组织的病理变化,免疫组化检测肝组织中转化生长因子β1、p-Smad3的表达;Western blot检测肝组织中转化生长因子β1、Smad3、p-Smad3、α-平滑肌肌动蛋白、Ⅰ型胶原蛋白和Ⅲ型胶原蛋白表达水平。结果与结论:①与m/m组和m/m+运动组小鼠相比,db/db组小鼠体质量、肝质量、肝脏指数、空腹血糖、三酰甘油、总胆固醇、低密度脂蛋白和肌酶水平均显著升高(P<0.01);高密度脂蛋白水平显著降低(P<0.01);转化生长因子β1、p-Smad3、α-平滑肌肌动蛋白、Ⅰ型胶原蛋白和Ⅲ型胶原蛋白表达水平显著升高(P<0.01);葡萄糖、胰岛素耐量测试的曲线下面积显著增加(P<0.01);肝组织病理染色显示大量炎症细胞浸润,脂滴增多,明显纤维化;②与db/db组相比,db/db+运动组小鼠体质量、肝质量、肝脏指数、空腹血糖、三酰甘油、总胆固醇、低密度脂蛋白和肌酶水平显著降低(P<0.05或P<0.01);高密度脂蛋白水平显著升高(P<0.05);转化生长因子β1、p-Smad3、α-平滑肌肌动蛋白、Ⅰ型胶原蛋白和Ⅲ型胶原蛋白表达显著降低(P<0.05或P<0.01);此外,糖耐量、胰岛素耐量测试的曲线下面积明显减少(P<0.01,P<0.05),肝脏病理损伤得到明显改善;③结果表明,有氧运动有效减轻了糖尿病小鼠肝纤维化,其机制可能与调控转化生长因子β/Smad信号通路有关。 展开更多
关键词 有氧运动 转化生长因子β Smad 信号通路 db/db 肝纤维化
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基于转录组学探讨当归芍药散对db/db小鼠肾脏保护作用的潜在机制
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作者 黄秋晴 黎柳 +2 位作者 李鸿 谭丹妮 喻嵘 《湖南中医药大学学报》 CAS 2024年第6期967-975,共9页
目的基于转录组学和实验验证探究当归芍药散对db/db糖尿病肾病小鼠肾脏的保护机制。方法25只8周龄造模成功的db/db小鼠按体质量随机均分为模型组(20 mL/kg蒸馏水)、达格列净组(1.3 mg/kg)、当归芍药散低剂量组(8.39 g/kg)、当归芍药散... 目的基于转录组学和实验验证探究当归芍药散对db/db糖尿病肾病小鼠肾脏的保护机制。方法25只8周龄造模成功的db/db小鼠按体质量随机均分为模型组(20 mL/kg蒸馏水)、达格列净组(1.3 mg/kg)、当归芍药散低剂量组(8.39 g/kg)、当归芍药散中剂量组(16.77 g/kg)、当归芍药散高剂量组(33.54 g/kg),每组5只;另选5只同龄db/m小鼠作为空白组(20 mL/kg蒸馏水)。每组灌胃1次/d,连续6周。给药结束后,检测各组小鼠体质量、空腹血糖(fasting blood glucose,FBG)、口服糖耐量试验(oral glucose tolerance test,OGTT)的曲线下面积(area under thecurve,AUC);采用全自动生化分析仪检测尿白蛋白肌酐比值(urea albumin creatinine ratio,UACR)、甘油三酯(triglyceride,TG)、总胆固醇(total cholesterol,TC);采用肌酐比色法检测血肌酐(serum creatinine,Scr);采用尿素比色法检测小鼠血尿素氮(blood urea nitrogen,BUN);采用HE染色观察肾脏组织病理形态;采用转录组学芯片技术检测小鼠肾组织差异基因,并对当归芍药散中剂量组差异基因进行KEGG富集分析;采用RT-PCR法检测表达量TPM>10的核心基因在肾脏组织中的mRNA表达水平。结果与空白组比较,模型组小鼠体质量、OGTT-AUC、FBG、UACR、Scr、BUN、TG、TC显著升高(P<0.01)。与模型组相比,达格列净组、当归芍药散各剂量组小鼠体质量、OGTT-AUC、FBG、UACR、Scr、BUN、TG、TC均降低(P<0.05,P<0.01)。与空白组相比,模型组共筛选出1129个差异基因,其中上调差异基因337个、下调差异基因792个。与模型组相比,当归芍药散共筛选出271个差异基因,其中上调差异基因195个、下调差异基因76个。空白组、模型组、当归芍药散中剂量组三组差异共表达基因57个,其中TPM>10的核心基因共12个,包括Gsta2、Cyp4a12a、Slc8a1、Abcc4、Cpeb4、Serpina1b、Npl、Aacs、Kap、Slc5a10、Tmem252、Ifi27l2a。12个核心基因的mRNA表达水平与转录组测序趋势相同。与模型组比较,当归芍药散中剂量组小鼠Gsta2、Abcc4、Slc8a1、NPL mRNA表达水平升高(P<0.05,P<0.01),Slc5a10、Tmem252 mRNA表达水平下降(P<0.05)。当归芍药散中剂量组差异基因富集于药物代谢-细胞色素P450、谷胱甘肽代谢、活性氧等相关通路。结论当归芍药散具有改善糖尿病肾病预后的作用,其机制可能与调控Gsta2、Slc5a10、Abcc4、Slc8a1、Tmem252、Npl等基因表达,调控细胞色素P450、谷胱甘肽代谢、活性氧等信号通路相关。 展开更多
关键词 当归芍药散 db/db小鼠 糖尿病肾病 转录组学 差异表达基因 活血利水
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我国部分地区A2dB1型传染性法氏囊病病毒新型变异株的鉴定及序列分析
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作者 张文英 于航博 +15 位作者 姜楠 王国栋 牛鑫鑫 黄萌萌 张玉龙 韩金泽 许萌萌 刘长军 王素艳 李凯 高立 崔红玉 张艳萍 陈运通 高玉龙 祁小乐 《中国家禽》 北大核心 2024年第9期194-200,共7页
为持续了解传染性法氏囊病病毒新型变异株(Novel variant infectious bursal disease virus,nVarIBDV)在我国流行情况,研究收集2021—2022年6个主要养禽地区疑似传染性法氏囊病(Infectious bursal disease,IBD)鸡病料,采用RT-PCR进行检... 为持续了解传染性法氏囊病病毒新型变异株(Novel variant infectious bursal disease virus,nVarIBDV)在我国流行情况,研究收集2021—2022年6个主要养禽地区疑似传染性法氏囊病(Infectious bursal disease,IBD)鸡病料,采用RT-PCR进行检测,并对11株IBDV代表毒株的基因组双节段代表区段VP2-HVR和VP1-B-marker进行基因测序及序列分析。结果显示:所检测病料的IBDV阳性率为20.65%(19/92),其中11株IBDV代表毒株均为A2dB1型nVarIBDV。研究表明,nVarIBDV在我国主要养禽地区仍持续流行,而且出现了值得注意的新的突变位点,有必要进行持续的IBDV流行病学监测。 展开更多
关键词 传染性法氏囊病病毒 新型变异株 A2db1型 流行病学
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Enhancing Dense Small Object Detection in UAV Images Based on Hybrid Transformer 被引量:1
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作者 Changfeng Feng Chunping Wang +2 位作者 Dongdong Zhang Renke Kou Qiang Fu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3993-4013,共21页
Transformer-based models have facilitated significant advances in object detection.However,their extensive computational consumption and suboptimal detection of dense small objects curtail their applicability in unman... Transformer-based models have facilitated significant advances in object detection.However,their extensive computational consumption and suboptimal detection of dense small objects curtail their applicability in unmanned aerial vehicle(UAV)imagery.Addressing these limitations,we propose a hybrid transformer-based detector,H-DETR,and enhance it for dense small objects,leading to an accurate and efficient model.Firstly,we introduce a hybrid transformer encoder,which integrates a convolutional neural network-based cross-scale fusion module with the original encoder to handle multi-scale feature sequences more efficiently.Furthermore,we propose two novel strategies to enhance detection performance without incurring additional inference computation.Query filter is designed to cope with the dense clustering inherent in drone-captured images by counteracting similar queries with a training-aware non-maximum suppression.Adversarial denoising learning is a novel enhancement method inspired by adversarial learning,which improves the detection of numerous small targets by counteracting the effects of artificial spatial and semantic noise.Extensive experiments on the VisDrone and UAVDT datasets substantiate the effectiveness of our approach,achieving a significant improvement in accuracy with a reduction in computational complexity.Our method achieves 31.9%and 21.1%AP on the VisDrone and UAVDT datasets,respectively,and has a faster inference speed,making it a competitive model in UAV image object detection. 展开更多
关键词 UAV images TRANSFORMER dense small object detection
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从DB到B-Ready:世界银行营商环境评价指标体系变化与中国应对之策
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作者 孙悦 范健 《社会科学辑刊》 北大核心 2024年第4期153-166,共14页
自2003年起,世界银行采用DB评价体系对全球主要经济体进行测度与排名,加速了各经济体营商环境的优化进程。然而,DB评价体系的科学性、合理性和客观性存在不足,无法适应所有国家的评估需求,也难以反映各国营商环境的真实水平。为了解决D... 自2003年起,世界银行采用DB评价体系对全球主要经济体进行测度与排名,加速了各经济体营商环境的优化进程。然而,DB评价体系的科学性、合理性和客观性存在不足,无法适应所有国家的评估需求,也难以反映各国营商环境的真实水平。为了解决DB评价体系的内生性问题,消弭其外部不适用性,世界银行推出了B-Ready评价体系,从监管框架、公共服务和整体效率“三位一体”层面重塑营商环境评价体系,使得评价范围更为全面、指标设计更加合理、评价方法更加科学。优化中国特色营商环境,应深入了解世界银行B-Ready评价体系的新内容,反思在新指标体系下我国优化营商环境面临的新挑战。在此基础上,剖析国际营商环境评价的新趋势,通过批判性借鉴、本土化考量与体系化回应,构建中国特色营商环境评价体系。 展开更多
关键词 db评价体系 B-Ready评价体系 营商环境 数字政府
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4种谷物膳食纤维对db/db小鼠血糖和炎症因子及肠道菌群的影响
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作者 刘欣果 李傲翔 +2 位作者 彭文婷 綦文涛 方微 《粮油食品科技》 CAS CSCD 北大核心 2024年第5期115-125,共11页
研究4种谷物膳食纤维(DF)对db/db小鼠血糖和炎症因子及肠道菌群的影响。用含有小麦(WDF)、糙米(BDF)、燕麦(ODF)和荞麦(BWDF)4种膳食纤维的日粮分别饲喂db/db小鼠,每两周测定空腹血糖(FBG)水平,并在第8周和14周时进行口服葡萄糖耐量实验... 研究4种谷物膳食纤维(DF)对db/db小鼠血糖和炎症因子及肠道菌群的影响。用含有小麦(WDF)、糙米(BDF)、燕麦(ODF)和荞麦(BWDF)4种膳食纤维的日粮分别饲喂db/db小鼠,每两周测定空腹血糖(FBG)水平,并在第8周和14周时进行口服葡萄糖耐量实验(OGTT)。14周时,采集粪便,分析菌群变化情况;收集血清,测定血脂和炎症因子水平。4种谷物DF均可降低db/db小鼠FBG和8周血糖曲线下面积(AUC)水平,改善血脂异常并降低血液促炎因子浓度(P<0.05)。4种谷物DF均可提高肠道菌群多样性,并改变不同菌群的丰度。其中,WDF主要增加粪杆菌属(Faecalibaculum)和罗姆布茨菌(Romboutsia)丰度;BDF增加了放线菌门(Actinobacteriota)丰度和厚壁菌门与拟杆菌门比例(F/B);ODF主要促进了另枝菌属(Alistipes)的增殖;BWDF增加了norank_f__Muribaculaceae丰度并降低了拟杆菌属(Bacteroides)水平。相关性分析显示F/B和Actinobacteriota与FBG、AUC、促炎因子(IL-8)及低密度脂蛋白胆固醇(LDL-C)水平呈显著负相关,与抗炎因子(IL-10)和高密度脂蛋白胆固醇(HDL-C)水平呈正相关,而Bacteroides与之相反;Alistipes、Faecalibaculum、Romboutsia分别与促炎因子IL-1β、IL-8、TNF-α呈负相关。4种谷物DF可通过增加肠道菌群多样性及对菌群的不同调节作用,改善2型糖尿病db/db小鼠的糖脂代谢紊乱和炎症反应。 展开更多
关键词 谷物膳食纤维 db/db小鼠 血糖 炎症因子 肠道菌群
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强杂波背景下调频步进DBS技术研究
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作者 周开心 刘丹阳 +2 位作者 朱永锋 张永杰 周剑雄 《系统工程与电子技术》 EI CSCD 北大核心 2024年第9期2960-2967,共8页
针对强地物杂波背景下弹载雷达目标检测与识别的技术难题,提出将高分辨距离像(high resolution range profile,HRRP)技术和多普勒波束锐化技术联合对地面进行二维高分辨成像,提高雷达在杂波下目标检测与识别的性能。该方法以线性调频步... 针对强地物杂波背景下弹载雷达目标检测与识别的技术难题,提出将高分辨距离像(high resolution range profile,HRRP)技术和多普勒波束锐化技术联合对地面进行二维高分辨成像,提高雷达在杂波下目标检测与识别的性能。该方法以线性调频步进频(linear frequency modulation stepped frequency,LFM-SF)信号为基本波形,首先对平台速度产生的多普勒效应等问题进行了详细讨论并校正;然后通过距离像抽取获得各帧对应的HRRP序列,并采用方位快速傅里叶变换(fast Fourier transform,FFT)实现方位高分辨;最后对实际飞行状态下平台造成的误差进行运动补偿,完成对波束内区域的二维分辨。实测数据的处理验证了所提算法的有效性与实用性。 展开更多
关键词 杂波 线性调频步进频 高分辨一维距离像 多普勒波束锐化 运动补偿
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青风藤活性成分对糖尿病db/db小鼠氧化应激、炎症反应及免疫功能的影响
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作者 刘均广 冯智丽 +4 位作者 李猛 高钰 周晓红 陈香美 高维娟 《河北中医药学报》 2024年第4期1-7,共7页
目的:探讨青风藤活性成分对糖尿病(diabetes mellitus,DM)db/db小鼠肾脏的保护作用及其机制研究。方法:30只6周龄雄性db/db小鼠随机分为模型组(等体积生理盐水),阳性组(195 mg/kg/d羟苯磺酸钙),盐酸青藤碱(Sinomenine Hydrochloride,SH... 目的:探讨青风藤活性成分对糖尿病(diabetes mellitus,DM)db/db小鼠肾脏的保护作用及其机制研究。方法:30只6周龄雄性db/db小鼠随机分为模型组(等体积生理盐水),阳性组(195 mg/kg/d羟苯磺酸钙),盐酸青藤碱(Sinomenine Hydrochloride,SH)低、中、高剂量组(31.2、62.4、124.8 mg/kg/d SH)5组,同时选取6只同周龄db/m小鼠设为对照组(等体积生理盐水),每日1次,定时灌胃给药,连续6 w。于12 w末观察各组小鼠一般情况,检测尿微量白蛋白(mAlb)、血肌酐(SCr)和血尿素氮(BUN)水平;试剂盒检测肾组织匀浆中丙二醛(MDA)、还原型谷胱甘肽(GSH)和超氧化物歧化酶(SOD)的水平;Luminex多因子检测技术测定血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)和白细胞介素-10(IL-10)的含量;ELISA法检测血清免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、免疫球蛋白A(IgA)及补体蛋白3(C3)的水平;苏木精-伊红(HE)和过碘酸-雪夫(PAS)染色观察肾脏组织病理形态变化;透射电镜观察肾脏超微结构的改变。结果:与模型组比较,阳性组和SH低、中、高剂量组小鼠mAlb、SCr和BUN水平均降低(P<0.05);肾组织匀浆中MDA水平降低(P<0.05),GSH水平和SOD活性均升高(P<0.05);血清中TNF-α、IL-1β、IL-6、IgG、IgM、IgA和补体C3水平均降低(P<0.05),IL-10水平升高(P<0.05);镜下肾小球损伤及肾小管上皮水肿情况均有所改善,肾组织损伤减轻。结论:青风藤活性成分对DM db/db小鼠的肾脏具有保护作用,其作用机制可能与改善氧化应激反应,缓解炎症反应及提高免疫功能有关。 展开更多
关键词 青风藤 糖尿病db/db小鼠 氧化应激 炎症反应 免疫功能
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基于DBS-RRT^(*)算法的机械臂复杂狭窄场景路径规划
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作者 秦鹏飞 王军茹 +1 位作者 张菂 孙广彬 《组合机床与自动化加工技术》 北大核心 2024年第6期62-69,共8页
针对目前RRT^(*)算法在机械臂复杂狭窄场景路径规划中,存在着规划时间长、路径冗长、狭窄环境规划成功率低的问题,提出一种动态偏置采样DBS-RRT^(*)(dynamic biased sampling RRT^(*))算法。首先,DBS-RRT^(*)算法采用动态偏置率,设计智... 针对目前RRT^(*)算法在机械臂复杂狭窄场景路径规划中,存在着规划时间长、路径冗长、狭窄环境规划成功率低的问题,提出一种动态偏置采样DBS-RRT^(*)(dynamic biased sampling RRT^(*))算法。首先,DBS-RRT^(*)算法采用动态偏置率,设计智能椭球子集采样作为偏向采样方法,利用自适应生长策略调整新节点的生长方向与步长,实现动态选择采样方法,提高采样效率,减少无效空间探索,改善搜索导向性的效果;然后,通过设计二维实验验证算法的有效性,实验证明DBS-RRT^(*)算法与RRT^(*)算法相比,规划效率更高,规划路径更短;最后,将DBS-RRT^(*)算法应用于复杂狭窄场景中的机械臂仿真实验。实验数据表明,DBS-RRT^(*)算法与RRT^(*)算法相比,规划路径长度减少了26%,规划时间减少了22.6%,成功率提高了32%。DBS-RRT^(*)算法在复杂狭窄场景中,相比RRT^(*)算法,能够更加有效地实现机械臂避障路径规划。 展开更多
关键词 dbS-RRT^(*)算法 动态偏置率 机械臂 路径规划 复杂狭窄场景
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Enhanced Object Detection and Classification via Multi-Method Fusion
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作者 Muhammad Waqas Ahmed Nouf Abdullah Almujally +2 位作者 Abdulwahab Alazeb Asaad Algarni Jeongmin Park 《Computers, Materials & Continua》 SCIE EI 2024年第5期3315-3331,共17页
Advances in machine vision systems have revolutionized applications such as autonomous driving,robotic navigation,and augmented reality.Despite substantial progress,challenges persist,including dynamic backgrounds,occ... Advances in machine vision systems have revolutionized applications such as autonomous driving,robotic navigation,and augmented reality.Despite substantial progress,challenges persist,including dynamic backgrounds,occlusion,and limited labeled data.To address these challenges,we introduce a comprehensive methodology toenhance image classification and object detection accuracy.The proposed approach involves the integration ofmultiple methods in a complementary way.The process commences with the application of Gaussian filters tomitigate the impact of noise interference.These images are then processed for segmentation using Fuzzy C-Meanssegmentation in parallel with saliency mapping techniques to find the most prominent regions.The Binary RobustIndependent Elementary Features(BRIEF)characteristics are then extracted fromdata derived fromsaliency mapsand segmented images.For precise object separation,Oriented FAST and Rotated BRIEF(ORB)algorithms areemployed.Genetic Algorithms(GAs)are used to optimize Random Forest classifier parameters which lead toimproved performance.Our method stands out due to its comprehensive approach,adeptly addressing challengessuch as changing backdrops,occlusion,and limited labeled data concurrently.A significant enhancement hasbeen achieved by integrating Genetic Algorithms(GAs)to precisely optimize parameters.This minor adjustmentnot only boosts the uniqueness of our system but also amplifies its overall efficacy.The proposed methodologyhas demonstrated notable classification accuracies of 90.9%and 89.0%on the challenging Corel-1k and MSRCdatasets,respectively.Furthermore,detection accuracies of 87.2%and 86.6%have been attained.Although ourmethod performed well in both datasets it may face difficulties in real-world data especially where datasets havehighly complex backgrounds.Despite these limitations,GAintegration for parameter optimization shows a notablestrength in enhancing the overall adaptability and performance of our system. 展开更多
关键词 BRIEF features saliency map fuzzy c-means object detection object recognition
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Confusing Object Detection:A Survey
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作者 Kunkun Tong Guchu Zou +5 位作者 Xin Tan Jingyu Gong Zhenyi Qi Zhizhong Zhang Yuan Xie Lizhuang Ma 《Computers, Materials & Continua》 SCIE EI 2024年第9期3421-3461,共41页
Confusing object detection(COD),such as glass,mirrors,and camouflaged objects,represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds,lev... Confusing object detection(COD),such as glass,mirrors,and camouflaged objects,represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds,leveraging deep learning methodologies.Despite garnering increasing attention in computer vision,the focus of most existing works leans toward formulating task-specific solutions rather than delving into in-depth analyses of methodological structures.As of now,there is a notable absence of a comprehensive systematic review that focuses on recently proposed deep learning-based models for these specific tasks.To fill this gap,our study presents a pioneering review that covers both themodels and the publicly available benchmark datasets,while also identifying potential directions for future research in this field.The current dataset primarily focuses on single confusing object detection at the image level,with some studies extending to video-level data.We conduct an in-depth analysis of deep learning architectures,revealing that the current state-of-the-art(SOTA)COD methods demonstrate promising performance in single object detection.We also compile and provide detailed descriptions ofwidely used datasets relevant to these detection tasks.Our endeavor extends to discussing the limitations observed in current methodologies,alongside proposed solutions aimed at enhancing detection accuracy.Additionally,we deliberate on relevant applications and outline future research trajectories,aiming to catalyze advancements in the field of glass,mirror,and camouflaged object detection. 展开更多
关键词 Confusing object detection mirror detection glass detection camouflaged object detection deep learning
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Floating Waste Discovery by Request via Object-Centric Learning
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作者 Bingfei Fu 《Computers, Materials & Continua》 SCIE EI 2024年第7期1407-1424,共18页
Discovering floating wastes,especially bottles on water,is a crucial research problem in environmental hygiene.Nevertheless,real-world applications often face challenges such as interference from irrelevant objects an... Discovering floating wastes,especially bottles on water,is a crucial research problem in environmental hygiene.Nevertheless,real-world applications often face challenges such as interference from irrelevant objects and the high cost associated with data collection.Consequently,devising algorithms capable of accurately localizing specific objects within a scene in scenarios where annotated data is limited remains a formidable challenge.To solve this problem,this paper proposes an object discovery by request problem setting and a corresponding algorithmic framework.The proposed problem setting aims to identify specified objects in scenes,and the associated algorithmic framework comprises pseudo data generation and object discovery by request network.Pseudo-data generation generates images resembling natural scenes through various data augmentation rules,using a small number of object samples and scene images.The network structure of object discovery by request utilizes the pre-trained Vision Transformer(ViT)model as the backbone,employs object-centric methods to learn the latent representations of foreground objects,and applies patch-level reconstruction constraints to the model.During the validation phase,we use the generated pseudo datasets as training sets and evaluate the performance of our model on the original test sets.Experiments have proved that our method achieves state-of-the-art performance on Unmanned Aerial Vehicles-Bottle Detection(UAV-BD)dataset and self-constructed dataset Bottle,especially in multi-object scenarios. 展开更多
关键词 Unsupervised object discovery object-centric learning pseudo data generation real-world object discovery by request
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Two-Layer Attention Feature Pyramid Network for Small Object Detection
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作者 Sheng Xiang Junhao Ma +2 位作者 Qunli Shang Xianbao Wang Defu Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期713-731,共19页
Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain les... Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain less information.Many current methods,particularly those based on Feature Pyramid Network(FPN),address this challenge by leveraging multi-scale feature fusion.However,existing FPN-based methods often suffer from inadequate feature fusion due to varying resolutions across different layers,leading to suboptimal small object detection.To address this problem,we propose the Two-layerAttention Feature Pyramid Network(TA-FPN),featuring two key modules:the Two-layer Attention Module(TAM)and the Small Object Detail Enhancement Module(SODEM).TAM uses the attention module to make the network more focused on the semantic information of the object and fuse it to the lower layer,so that each layer contains similar semantic information,to alleviate the problem of small object information being submerged due to semantic gaps between different layers.At the same time,SODEM is introduced to strengthen the local features of the object,suppress background noise,enhance the information details of the small object,and fuse the enhanced features to other feature layers to ensure that each layer is rich in small object information,to improve small object detection accuracy.Our extensive experiments on challenging datasets such as Microsoft Common Objects inContext(MSCOCO)and Pattern Analysis Statistical Modelling and Computational Learning,Visual Object Classes(PASCAL VOC)demonstrate the validity of the proposedmethod.Experimental results show a significant improvement in small object detection accuracy compared to state-of-theart detectors. 展开更多
关键词 Small object detection two-layer attention module small object detail enhancement module feature pyramid network
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Rail-Pillar Net:A 3D Detection Network for Railway Foreign Object Based on LiDAR
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作者 Fan Li Shuyao Zhang +2 位作者 Jie Yang Zhicheng Feng Zhichao Chen 《Computers, Materials & Continua》 SCIE EI 2024年第9期3819-3833,共15页
Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional(2D)images,such as short detection distance,strong influence of environment and lack of distance information,w... Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional(2D)images,such as short detection distance,strong influence of environment and lack of distance information,we propose Rail-PillarNet,a three-dimensional(3D)LIDAR(Light Detection and Ranging)railway foreign object detection method based on the improvement of PointPillars.Firstly,the parallel attention pillar encoder(PAPE)is designed to fully extract the features of the pillars and alleviate the problem of local fine-grained information loss in PointPillars pillars encoder.Secondly,a fine backbone network is designed to improve the feature extraction capability of the network by combining the coding characteristics of LIDAR point cloud feature and residual structure.Finally,the initial weight parameters of the model were optimised by the transfer learning training method to further improve accuracy.The experimental results on the OSDaR23 dataset show that the average accuracy of Rail-PillarNet reaches 58.51%,which is higher than most mainstream models,and the number of parameters is 5.49 M.Compared with PointPillars,the accuracy of each target is improved by 10.94%,3.53%,16.96%and 19.90%,respectively,and the number of parameters only increases by 0.64M,which achieves a balance between the number of parameters and accuracy. 展开更多
关键词 Railway foreign object light detection and ranging(LiDAR) 3D object detection PointPillars parallel attention mechanism transfer learning
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A Secure and Cost-Effective Training Framework Atop Serverless Computing for Object Detection in Blasting
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作者 Tianming Zhang Zebin Chen +4 位作者 Haonan Guo Bojun Ren Quanmin Xie Mengke Tian Yong Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2139-2154,共16页
The data analysis of blasting sites has always been the research goal of relevant researchers.The rise of mobile blasting robots has aroused many researchers’interest in machine learning methods for target detection ... The data analysis of blasting sites has always been the research goal of relevant researchers.The rise of mobile blasting robots has aroused many researchers’interest in machine learning methods for target detection in the field of blasting.Serverless Computing can provide a variety of computing services for people without hardware foundations and rich software development experience,which has aroused people’s interest in how to use it in the field ofmachine learning.In this paper,we design a distributedmachine learning training application based on the AWS Lambda platform.Based on data parallelism,the data aggregation and training synchronization in Function as a Service(FaaS)are effectively realized.It also encrypts the data set,effectively reducing the risk of data leakage.We rent a cloud server and a Lambda,and then we conduct experiments to evaluate our applications.Our results indicate the effectiveness,rapidity,and economy of distributed training on FaaS. 展开更多
关键词 Serverless computing object detection BLASTING
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SMSTracker:A Self-Calibration Multi-Head Self-Attention Transformer for Visual Object Tracking
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作者 Zhongyang Wang Hu Zhu Feng Liu 《Computers, Materials & Continua》 SCIE EI 2024年第7期605-623,共19页
Visual object tracking plays a crucial role in computer vision.In recent years,researchers have proposed various methods to achieve high-performance object tracking.Among these,methods based on Transformers have becom... Visual object tracking plays a crucial role in computer vision.In recent years,researchers have proposed various methods to achieve high-performance object tracking.Among these,methods based on Transformers have become a research hotspot due to their ability to globally model and contextualize information.However,current Transformer-based object tracking methods still face challenges such as low tracking accuracy and the presence of redundant feature information.In this paper,we introduce self-calibration multi-head self-attention Transformer(SMSTracker)as a solution to these challenges.It employs a hybrid tensor decomposition self-organizing multihead self-attention transformermechanism,which not only compresses and accelerates Transformer operations but also significantly reduces redundant data,thereby enhancing the accuracy and efficiency of tracking.Additionally,we introduce a self-calibration attention fusion block to resolve common issues of attention ambiguities and inconsistencies found in traditional trackingmethods,ensuring the stability and reliability of tracking performance across various scenarios.By integrating a hybrid tensor decomposition approach with a self-organizingmulti-head self-attentive transformer mechanism,SMSTracker enhances the efficiency and accuracy of the tracking process.Experimental results show that SMSTracker achieves competitive performance in visual object tracking,promising more robust and efficient tracking systems,demonstrating its potential to providemore robust and efficient tracking solutions in real-world applications. 展开更多
关键词 Visual object tracking tensor decomposition TRANSFORMER self-attention
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一种基于LTCC技术的3 dB电桥设计与制作
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作者 边丽菲 周文瑾 +2 位作者 袁野 何舒玮 王栋 《磁性材料及器件》 CAS 2024年第1期58-61,共4页
针对当前通信系统对3 dB电桥等多种无源器件多频带和小型化等要求,利用低温共烧陶瓷(LTCC)工艺设计了一款具有新型结构的3 dB 90°电桥,采用蛇形和螺旋宽边耦合带状线的方式,实现了电桥的小型化和超宽带。通过软件ANSYS HFSS对电桥... 针对当前通信系统对3 dB电桥等多种无源器件多频带和小型化等要求,利用低温共烧陶瓷(LTCC)工艺设计了一款具有新型结构的3 dB 90°电桥,采用蛇形和螺旋宽边耦合带状线的方式,实现了电桥的小型化和超宽带。通过软件ANSYS HFSS对电桥进行三维建模,并在LTCC工艺线加工制作,实际制作的电桥的测量结果与仿真结果几乎一致。研制的3 dB电桥的工作频率为1~2.7 GHz,尺寸为3.2 mm×1.6 mm×0.95 mm,相位不平衡度小于±5°,幅度不平衡度小于2 dB,带内插损小于2 dB,隔离度大于15 dB,输入电压驻波比小于1.5。 展开更多
关键词 3 db电桥 低温共烧陶瓷 宽边耦合 小型化 超宽带
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