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基于各向异性尺度Junction的图像拼接
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作者 向天烛 薛楠 +1 位作者 夏桂松 张良培 《信号处理》 CSCD 北大核心 2017年第4期465-471,共7页
图像拼接一般采用特征点匹配和全局变换,特征点仅包含位置信息,无法表达图像局部结构信息,且全局变换模型只适用于旋转拍摄和远距离拍摄情况,当图像视角变化较大时,容易产生明显的配准误差,降低拼接图像的质量。为此,本文提出了一种基... 图像拼接一般采用特征点匹配和全局变换,特征点仅包含位置信息,无法表达图像局部结构信息,且全局变换模型只适用于旋转拍摄和远距离拍摄情况,当图像视角变化较大时,容易产生明显的配准误差,降低拼接图像的质量。为此,本文提出了一种基于各向异性尺度Junction特征的图像拼接方法。Junction不仅包含点特征信息,还具有线特征信息,表达了图像重要的局部几何结构。基于Junction特征的配准在特征点配准的基础上,利用分支线信息进一步约束和优化配准,同时结合局部单应变换模型,可以较好地容忍图像局部变形,从而提高配准精度,改善拼接效果。实验验证了本文算法的有效性。 展开更多
关键词 图像拼接 各向异性尺度junction junction匹配 局部变换 配准优化
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Operation reliability for on-ramp junction of urban freeway 被引量:2
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作者 慈玉生 吴丽娜 +1 位作者 凌贤长 裴玉龙 《Journal of Central South University》 SCIE EI CAS 2011年第1期266-270,共5页
A disorder situation of traffic operation always appears in on-ramp junction area of urban freeway,because the operation action for vehicles presents the weaving condition,especially for different vehicle types.Based ... A disorder situation of traffic operation always appears in on-ramp junction area of urban freeway,because the operation action for vehicles presents the weaving condition,especially for different vehicle types.Based on the analysis on the cellular automata theory,and combining with on-site survey data,several key parameters were defined,namely,cellular length,cellular speed,cellular acceleration,updating time interval.In addition,cellular acceleration rule,cellular deceleration rule,random rule,lane-changing rule and other micro-simulation rules were set,and cellular automaton micro-simulation model was set up.Further-more,a micro-simulation module was developed for traffic operation actions of on-ramp junction with Matlab toolbox.Finally,a simulation experiment for traffic operation reliability was done with this micro-simulation module,and the situation of change for on-ramp junction area was obtained under the conditions of different mainline design speed,acceleration lane length,vehicle generation probability and lane-changing probability.The results show that operation reliability for on-ramp junction is determined by the parameters of the probability of vehicle generation and the length of acceleration lane,especially for on-ramp. 展开更多
关键词 on-ramp junction operation reliability cellular automata simulation model
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Using junction trees for structural learning of Bayesian networks 被引量:1
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作者 Mingmin Zhu Sanyang Liu +1 位作者 Youlong Yang Kui Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期286-292,共7页
The learning Bayesian network (BN) structure from data is an NP-hard problem and still one of the most exciting chal- lenges in the machine learning. In this work, a novel algorithm is presented which combines ideas... The learning Bayesian network (BN) structure from data is an NP-hard problem and still one of the most exciting chal- lenges in the machine learning. In this work, a novel algorithm is presented which combines ideas from local learning, constraint- based, and search-and-score techniques in a principled and ef- fective way. It first reconstructs the junction tree of a BN and then performs a K2-scoring greedy search to orientate the local edges in the cliques of junction tree. Theoretical and experimental results show the proposed algorithm is capable of handling networks with a large number of variables. Its comparison with the well-known K2 algorithm is also presented. 展开更多
关键词 Bayesian network (BN) junction tree scoring function structural learning conditional independence.
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Non-junctional Cx32 mediates anti-apoptotic and pro-tumor effects via epidermal growth factor receptor in human cervical cancer cells 被引量:3
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作者 Yi-fan ZHAO Yong-chang LAI +8 位作者 Hui GE Yun-quan GUO Xue FENG Jia SONG Qin WANG Li-xia FAN Andrew L HARRIS Xi-yan WANG Liang TAO 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期971-972,共2页
OBJECTIVE To investigate the role of connexin proteins(Cx),which form gap junctions(GJ),in progression and chemotherapeutic sensitivity of cervical cancer(CaC x).METHODS We analyze the expression of Cx26,Cx30,Cx32 and... OBJECTIVE To investigate the role of connexin proteins(Cx),which form gap junctions(GJ),in progression and chemotherapeutic sensitivity of cervical cancer(CaC x).METHODS We analyze the expression of Cx26,Cx30,Cx32 and Cx43 in human specimens consisting of:Normal cervix(n=78),CaCx FIGO stageⅠ(n=148),CaCx FIGO stageⅡ(n=165).In CaCx cell lines,Hela-Cx32(induced expression by doxycycline),C-33A(endogenously express Cx32)and si Ha(transiently transfected plasmid with Cx32),we detected the role of Cx32 against tostreptonigrin/cisplatin-induced apopotosisin presence or absence of functional GJ through using GJ inhibitors or low density cultural.Furtherly,we observed the relativity of Cx32 and EGFR expression in human specimens.Also,we detected the role of EGFR signaling pathway in the process of Cx32 anti-apoptosis through suppressed EGFR expression by inhibitors or si RNA sequences in cell lines.RESULTS We firstly demonstrated the expression of Cx32 was highly upregulated and accumulated in cytoplasm in the CaCx specimens,and the degree of upregulation correlated with advanced FIGO stages.Thus,in three human cervical cell lines,Cx32 was shown to suppress apoptosis when GJ formation is inhibited.No matter in cases of CaCx or cell lines,Cx32 expression was highly correlated with expression of EGFR and the EGFR pathway is an essential component of the Cx32-induced anti-apoptotic effect.CONCLUSION Cx32,traditionally tumor suppressive protein,was shown to be tumor protective against chemotherapy through EGFR pathway in a GJ-independent way. 展开更多
关键词 gap-junction CONNEXIN cervical cancer apoptosis epidermal growth factor receptor
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TECTONIC EVOLUTION OF THE GARZE—LITANG PLATE JUNCTION, WITH PARTICULAR REFERENCE TO THE GOLD DEPOSITS
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作者 WT5,5”BZ]Zou Guangfu 1, Mao Ying\+2, Mao Junyi\+3 (1 Chengdu Institute of Geology and Mineral resources,Chengdu 610082, China 2 Chengdu Comprehensive rock and mineral Testing Center, Chengdu 610081, China 3 Regional Geological Surveying, Sichuan 《地学前缘》 EI CAS CSCD 2000年第S1期407-408,共2页
Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to... Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5~35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes. 展开更多
关键词 tectonic evolution METALLOGENESIS gold deposit Garze—Litang PLATE junction the eastern part of Qinghai—Xizang plateau China
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Gap junctions enhance the antiproliferative effect by transfer of microRNAs in glioma cells
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作者 Yue-xia PENG Liang TAO Qin WANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1023-1023,共1页
OBJECTIVE To investigate the permeability of gap junction composed of connexin 43(Cx43)for micro RNAs(mi RNAs)and the impact of gap junction-mediated transfer of mi RNAs in glioma U87 cells.METHODS Co-culture assay de... OBJECTIVE To investigate the permeability of gap junction composed of connexin 43(Cx43)for micro RNAs(mi RNAs)and the impact of gap junction-mediated transfer of mi RNAs in glioma U87 cells.METHODS Co-culture assay demonstrated the transmission of miR NAs through gap junction channel into adjacent cells.U87 cells were labeled with green fluorescein protein(GFP)as receivers and cells were transfected mi RNAs as donors.Receiver cells and donor cells were mixed together in a ratio of 1∶1.After 12 h co-culture,cells were separated using a BD influx flow cytometer based on the GFP labeled.Quantitative real-time polymerase chain reaction(q RT-PCR)was applied detect to the expressions of miR NAs and Cx43 mR NA.Western blotting was performed to detect the protein expressions of Cx43 and GFP in U87 cells.CCK-8 assay is used to detect cell growth.RESULTS Co-culture assays demonstrated mi R-34a could transfer between U87 cells.The role of the contact independent could also transfer of miR-34a.Gap junctions inhibitor(CBX and 18-α-GA)showed lower miR-34a expression than co-culture group,whereas gap junctions enhancer(RA and Galanglin)enhanced miR-34a expression.Knockdown of Cx43 could significantly decrease the transferring of miR-34a between U87 cells.Different length of miR NAs(miR-1827,miR-144,miR-203a and miR-1183)were similar to the expression of miR-34a between U87 cells.Additionally,we demonstrated that gap junctions mediate the effect of antiproliferation mediated by mi R-34a in U87 cells.The functional inhibition of gap junctions using either si RNA or inhibition eliminated the miR-34a mediated antiproliferation,whereas the enhancement of gap junctions treatment augmented this mi R34a-mediated antiproliferation.CONCLUSION Our study demonstrates that gap junction composed of Cx43-mediated transfer mi RNAs in different length of nucleotides and gap junction-mediated transfer of mi R-34a enhance the antiproliferative effect in glioma U87 cells. 展开更多
关键词 gap junction CONNEXIN microRNA ANTIPROLIFERATIVE
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Mechanical allodynia and affective behavior are improved by INI-0602,a gap junction hemichannel inhibitor,in a rat model of neuropathic pain induced by sciatic nerve injury
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作者 ZHANG Xiao-min FAN Li-xia +5 位作者 PENG Yue-xia SONG Qi XIANG Yu-ke WU Wei-li WANG Qin TAO Liang 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2016年第10期1027-1028,共2页
OBJECTIVE To investigated the effects of INI-0602 on nociceptive reflex,depression-associated andanxiety-related behaviors caused by neuropathic pain in sciatic nerve injury rats.METHODS Male rat were subjected to sci... OBJECTIVE To investigated the effects of INI-0602 on nociceptive reflex,depression-associated andanxiety-related behaviors caused by neuropathic pain in sciatic nerve injury rats.METHODS Male rat were subjected to sciatic nerve injury(SNI)or sham surgery.Rat received daily treatment with INI-0602 intrathecally,at a dose of 0.25μg/10μL.The response frequency to mechanical allodynia in animals was measured with von Frey hairs on day 1,3,5,7,14,21.Rats were evaluated in the forced swimming test(FST)test,tail suspension test(TST),sucrose preference test(SPT)for depression-like behavior.We performed open field test(OFT)and elevated plus-maze test(EPM)to evaluate anxiety-associated behaviors.Besides,we investigated the alterations of NMDA receptor and the brain-derived neurotrophic factor(BDNF)and also the expression of connexin43 and connexin32,structure protein of gap junction channel,on the protein level and the number of activated astrocyte showed by immunohistochemical.RESULTS The SNI procedure produced mechanical allodynia and accompanied with depressive-like and anxiety-like behavior.Treatment with INI-0602 produced a significant analgesic effect in SNI rats at day 7(model+NS:11.017±1.506 g;model+INI-0602:31.157±1.532 g,P<0.01),and still obviously on the 21th day(31.067±1.787,P<0.01).INI-0602 could also improve the performance of sciatic nerve injury rats among program behavior tests related to depression and anxiety.In parallel with relief of pain,the alterations of NMDA receptor and the brain-derived neurotrophic factor(BDNF),involved in central sensitization and synaptic plasticity,were investigated.INI-0602 not only could inhibited spared nerve injury induced up-regulated of NR2B and phosphorylation NR2B in early and late neuropathic pain(early phase:Nr2b:2.897±0.228,P<0.01;p-Nr2b:2.984±0.236,P<0.01;late phase:Nr2b:2.594±0.187,P<0.01;p-Nr2b:3.124±0.330,P<0.01),but also could inhibit the increased of BDNF in the early(model+NS:3.637±0.381,model+INI-0602:1.148±0.372,P<0.01)and upregulate the BDNF in late stage(model+NS:0.438±0.103,model+INI-0602:1.222±0.092,P<0.01).Meanwhile,INI-0602 significantly decreased the expression of connexin43 and connexin32,structure protein of gap junction channel,on the protein level and the number of activated astrocyte showed by immunohistochemical.CONCLUSION INI-0602 blocked behavioral changes induced by neuropathic pain,suggesting that it might be a promising pharmacological approach of painemotion diseases. 展开更多
关键词 INI-0602 gap junction hemichannel inhibitor neuropathic pain DEPRESSION ANXIETY
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Gap junctions enhance the antiproliferative effect of microrna-34a in glioma cells
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作者 PENG Yue-xia 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2016年第10期1077-1077,共1页
OBJECTIVE To investigate the effect of gap junctions on the anti-tumor function induced by mi R-34a in glioma U87 cells.METHODS 1.Transfection(miR-34a mimics were transfected into glioma cells to upregulate their expr... OBJECTIVE To investigate the effect of gap junctions on the anti-tumor function induced by mi R-34a in glioma U87 cells.METHODS 1.Transfection(miR-34a mimics were transfected into glioma cells to upregulate their expression);2.Co-culture assay(U87cells were transfected with mi R-34a co-cultured with U87 cells that was transfected PCMV-eG FP plasmid);3.Flow cytometry analysis(select the e GFP labed U87 cells);4.RNA isolation and real-time PCR;5.CCK-8 assay;6.Western blotting.RESULTS Mi R-34a mimics transfered between the U87 cells.Parachute assay showed that GJ inhibition(CBX and 18-α-GA)can decrease mi R-34a expression than co-culture group.RA and galanglin enhanced mi R-34a expression than co-culture group.Mi R-34a relative expression reduced after co-culture,while gap junctions composed of Cx43 were down-regulated by sh RNA.Transfected with mi R-34a mimics reduced the survival of U87 cells in a dose-dependent manner.To more specifically establish the role of GJIC in mi R-34a induced growth inhibition of U87 cells,si RNA was used to knockdown the expression of Cx43,the dominant connexin expressed in U87 cells.CCK-8 assay showed that siR NAs have no effect on cell growth,but they could aggravate the growth inhibition of miR-34a to U87 cels.CONCLUSION Gap junctions enhance the antiproliferative effect of miR NA-34a in glioma cells. 展开更多
关键词 micro RNA-34a gap junction PROLIFERATION GLIOMA
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A STUDY OF SILICON AVALANCHE COLD MICRO-CATHODE USING ULTRA-SHALLOW PN+ JUNCTION
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作者 Li Qiong, Tang Shihao, Yaun Meiying, Xue Zheng, Xu Jingang Department of Electronics Science and Technology East China Normal University, Shanghai 200062 China Lin ChengluShanghai Institute of Metallurgy, Academia Sinica Chang Ning Road 865, Shanghai 200050 China Zhang Duan Wu Junlei Shanghai Vacuum Electrical Device Ltd. Jiao Zhou Road 485, Shanghai 200040 China 《真空科学与技术学报》 EI CAS CSCD 1992年第Z1期239-242,共4页
The structure, fabrication and emission characteristics of a silicon cold micro-cathode using ultra-shallow PN+ junction are presented. Implantation of As+ with a energy around 12 kev, rapid thermal annealing combined... The structure, fabrication and emission characteristics of a silicon cold micro-cathode using ultra-shallow PN+ junction are presented. Implantation of As+ with a energy around 12 kev, rapid thermal annealing combined with argon sputtering are used for forming ultra-shallow pn+ junction, whose depth is lower than 30nm. In a vacuum system Ⅰ-Ⅴcharacteristics were measured. The stability problem which was found in the devices testing is also discussed in this paper. 展开更多
关键词 junction A STUDY OF SILICON AVALANCHE COLD MICRO-CATHODE USING ULTRA-SHALLOW PN
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Giant aneurysm at the junction of the internal carotid and persistent primitive trigeminal artery (PPTA) treated with endovascular GDC coiling, a case report of experience in Ramathibodi hospital
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作者 P. Jiarakongmun S. Pongpech J. Suvikrom 《介入放射学杂志》 CSCD 2004年第S1期86-87,共2页
关键词 PPTA treated with endovascular GDC coiling a case report of experience in Ramathibodi hospital Giant aneurysm at the junction of the internal carotid and persistent primitive trigeminal artery
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Thyristor Junction Temperature Estimation Based on Measured Temperature of Molybdenum Flat 被引量:5
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作者 ZHANG Chunyu LI Chengrong +2 位作者 HAN Xiaohui ZHA Kunpeng TANG Guangfu 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0026-I0026,1,共1页
为获得较准确的晶闸管结温,提出了基于晶闸管钼层实测温度计算结温的共扼梯度算法。分析了共轭梯度法用于求解结温的具体步骤,并通过FORTRAN语言编译形成LOG命令流,导入ANSYS软件中来实现算法,该方法对于未知的低频分量,以较少的迭代次... 为获得较准确的晶闸管结温,提出了基于晶闸管钼层实测温度计算结温的共扼梯度算法。分析了共轭梯度法用于求解结温的具体步骤,并通过FORTRAN语言编译形成LOG命令流,导入ANSYS软件中来实现算法,该方法对于未知的低频分量,以较少的迭代次数即可以得到准确解,对于未知的高频分量,通过多次的迭代也能够获得准确的返溯值,因而具备处理多个未知量且收敛速度快的优点。以KPD3000-72型晶闸管应用于直流输电领域为例,分别在直流稳态、单波次浪涌电流和3波次浪涌电流的试验条件下进行计算,结果表明所得结温准确,为传统热阻抗法提供了校核的依据。 展开更多
关键词 温度变化 晶闸管 结温 估计 平板 外国公司 瞬态工况 热阻抗
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红景天苷对心肌缺血-再灌注损伤大鼠内质网应激与Cx43的作用 被引量:1
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作者 黄媛恒 何阳 +3 位作者 黄晓亮 韦学 吴耀生 李映新 《医药导报》 北大核心 2025年第3期366-371,共6页
目的研究红景天苷(Sal)对心肌缺血-再灌注损伤(MIRI)大鼠内质网应激和缝隙连接蛋白43(Cx43)的作用。方法将SD大鼠随机分为假手术组(Sham)、MIRI组、Sal小剂量组(Sal-L)、Sal大剂量组(Sal-H)。Sham组与MIRI组腹腔注射0.9%氯化钠溶液10 mL... 目的研究红景天苷(Sal)对心肌缺血-再灌注损伤(MIRI)大鼠内质网应激和缝隙连接蛋白43(Cx43)的作用。方法将SD大鼠随机分为假手术组(Sham)、MIRI组、Sal小剂量组(Sal-L)、Sal大剂量组(Sal-H)。Sham组与MIRI组腹腔注射0.9%氯化钠溶液10 mL·kg^(-1)·d^(-1);Sal-L组与Sal-H组腹腔注射Sal12、36 mg·kg^(-1)·d^(-1)。均每天1次,连续3 d。末次给药30 min后,除Sham组外,其余组制备MIRI模型。苏木精-伊红(HE)染色观察心肌组织病理改变,原位末端转移酶标记技术(TUNEL)测定细胞凋亡率,实时定量基因扩增荧光检测系统(q-PCR)与蛋白印迹法(Western blotting)检测葡萄糖调节蛋白78(GRP78)、半胱氨酸天冬氨酸蛋白酶12(Caspase12)、CCAAT/增强子结合蛋白同源蛋白(CHOP)等内质网应激相关因子以及Cx43的基因及蛋白表达。结果与MIRI组比较,Sal各剂量组心肌损伤不同程度减轻,Sal-H组心肌细胞凋亡率降低(P<0.05);Sal各剂量组Cx43基因表达均上调,GRP78、Caspase12、CHOP基因表达下调;Sal各剂量组Cx43蛋白表达均上调、GRP78蛋白表达下调,Sal-H组CHOP、Bax、Caspase12、cleaved-Caspase3蛋白表达下调,Bcl-2蛋白表达上调(P<0.05)。结论红景天苷对心肌细胞具有保护作用,其机制可能与抑制内质网应激所致细胞凋亡和Cx43代谢失衡有关。 展开更多
关键词 红景天苷 缺血-再灌注 内质网应激 细胞凋亡 缝隙连接蛋白
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基于结点热光效应的点热源非接触式温度传感器 被引量:2
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作者 刘梅 白鑫 +2 位作者 王嘉诚 周小彤 王志明 《仪器仪表学报》 北大核心 2025年第3期288-295,共8页
传统点热源温度测量方法包括热电偶、电阻温度计和红外测温等,但它们通常存在体积较大、响应速度较慢或难以实现微小区域精确测量的局限性。为此,设计并开发了一种基于光波导交叉结点和热光效应的温度传感器,实现了对小尺寸点热源的非... 传统点热源温度测量方法包括热电偶、电阻温度计和红外测温等,但它们通常存在体积较大、响应速度较慢或难以实现微小区域精确测量的局限性。为此,设计并开发了一种基于光波导交叉结点和热光效应的温度传感器,实现了对小尺寸点热源的非接触式温度测量。采用3D打印法制备了不同形态的光敏树脂结点,激光照射在结点交叉处,结点将激光分散到其分支结构上;氧化铝陶瓷加热片作为点热源提供小范围恒定温度,利用可调压电源实现对其温度的调节。加热片散发的热量改变结点材料的折射率(即热光效应),从而改变其分支出射光强度,光强的变化通过分支末端的光电二极管实时检测。实验证实了该传感器的温度灵敏特性和线性响应特性。结果表明,该传感器在一定范围温度变化中(330℃~554℃)的测量精度优异,具有良好的稳定性和重复性。在465℃~554℃范围内,传感器具有良好的线性特性,检测灵敏度可达-9.4 mV/℃,传感器的重复性误差δR在1.41%~2.11%之间。该方案提供了一种结构简单、成本低的微纳点热源温度检测新方法,为微型化、高灵敏、非接触式温度传感器的设计提供了新的思路,在医疗保健、激光加工和3D打印等领域的温度监测方面具有很大的应用潜力。 展开更多
关键词 光波导结点 温度传感器 点热源 热光效应 光电二极管
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基于双晶结的高温超导量子干涉器件研制
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作者 钟青 孙永 +4 位作者 徐达 陈建 陈晴 李劲劲 王雪深 《计量学报》 北大核心 2025年第8期1091-1096,共6页
基于高温超导约瑟夫森结的超导量子干涉器件(SQUID),工作在液氮温区、运行成本低,可应用于生物磁测、地球物理勘测、材料无损评估、磁性粒子探测等方面的微弱磁场测量。所述SQUID是在钛酸锶(SrTiO_(3))双晶衬底上生长钇钡铜氧(YBCO)/金(... 基于高温超导约瑟夫森结的超导量子干涉器件(SQUID),工作在液氮温区、运行成本低,可应用于生物磁测、地球物理勘测、材料无损评估、磁性粒子探测等方面的微弱磁场测量。所述SQUID是在钛酸锶(SrTiO_(3))双晶衬底上生长钇钡铜氧(YBCO)/金(Au)双层膜,通过紫外光刻、离子束刻蚀等技术制备的。在液氮温区测量了超导量子干涉器件的电压-电流(V-I)特性曲线,磁通电压特性曲线(Φ-V)和频率-磁通噪声曲线。器件的磁通电压转换系数为83.1μV/Φ_(0)(Φ_(0)为磁通量子),器件的有效面积达到0.45 mm^(2),在10 kHz频率处,磁通噪声和磁场噪声分别为37.0×10^(-6)Φ_(0)·Hz^(-1/2)和168.9 fT·Hz^(-1/2)。 展开更多
关键词 电磁计量 高温超导量子干涉器件 双晶结 钇钡铜氧
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腰椎后路减压内固定术后远端交界性峡部裂滑脱的危险因素分析及治疗选择
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作者 王永强 袁磊 +1 位作者 李危石 刘晓光 《中国脊柱脊髓杂志》 北大核心 2025年第3期243-252,共10页
目的:探讨腰椎后路减压内固定术后远端交界性峡部裂滑脱(distal junctional isthmic spondylolisthesis,DJIS)发生的危险因素及治疗方式。方法:回顾性分析2015年1月~2022年1月在我院接受治疗的10例后路减压内固定术后发生DJIS的患者,男7... 目的:探讨腰椎后路减压内固定术后远端交界性峡部裂滑脱(distal junctional isthmic spondylolisthesis,DJIS)发生的危险因素及治疗方式。方法:回顾性分析2015年1月~2022年1月在我院接受治疗的10例后路减压内固定术后发生DJIS的患者,男7例,女3例;年龄45~75岁(63.4±10.3岁),纳入DJIS组。按照年龄、性别、术前诊断、手术节段及手术方式匹配,以1∶2比例选取同期因腰椎退变性疾病在我院接受后路减压内固定术但未出现DJIS的患者作为对照组(20例)。比较两组患者的一般资料[体重指数(body mass index,BMI)、L1椎体CT值、骨质疏松患者比例]、下端椎椎板切除范围(下端椎椎板横向减压百分比、棘突切除百分比)、初次手术后骨盆入射角(pelvic incidence,PI)、腰椎前凸角(lumbar lordosis,LL)、骨盆倾斜角(pelvic tilt,PT)、骶骨倾斜角(sacral slope,SS)等,分析腰椎后路减压内固定术后DJIS发生的危险因素,总结腰椎后路减压内固定术后DJIS的治疗方法。结果:DJIS组患者的BMI显著性高于对照组(27.4±4.1kg/m~2vs. 23.7±3.4kg/m~2,P<0.001),L1椎体CT值显著性低于对照组(105.2±43.9HU vs. 133.5±23.5HU,P=0.028),骨质疏松患者比例高于对照组(70%vs. 10%,P=0.003)。DJIS组患者的PI(52.5±8.8°vs. 45.8±7.4°,P<0.05)和初次术后LL(47.4±14.3°vs. 36.5±10.6°,P<0.05)均显著性高于对照组,PT和SS两组无显著性差异(P>0.05);下端椎椎板横向减压百分比[(89.3±9.0)%vs.(78.0±3.2)%,P<0.05]和下端椎棘突切除百分比[(51.1±16.1)%vs.(39.3±9.1)%,P<0.05]显著性高于对照组。8例DJIS患者行远端减压、滑脱复位固定融合术,翻修术后生活质量评分显著性改善;2例临床症状不重,采取保守治疗,随访过程未诉症状加重。结论:高BMI、骨质疏松、高PI以及术中远端椎椎板切除范围过广是腰椎后路减压内固定术后发生DJIS的可能危险因素。 展开更多
关键词 腰椎减压固定融合术 机械性并发症 远端交界性失败 峡部裂滑脱 翻修手术
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食管胃结合部腺癌皮肤转移1例报道及疗效分析
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作者 李浩 邓瑾 +2 位作者 刘沛华 张泉涌 蔡寨 《中国癌症杂志》 北大核心 2025年第6期601-604,共4页
1病例资料患者,女性,79岁。自2024年10月起,患者因反复出现吞咽困难,并伴有反酸、乏力、消瘦及食欲下降等症状,于2024年11月15日于当地医院行胃镜检查,结果提示胃底贲门癌侵及食管;胸部CT检查提示食管下段胃底贲门部黏膜不均匀增厚,考... 1病例资料患者,女性,79岁。自2024年10月起,患者因反复出现吞咽困难,并伴有反酸、乏力、消瘦及食欲下降等症状,于2024年11月15日于当地医院行胃镜检查,结果提示胃底贲门癌侵及食管;胸部CT检查提示食管下段胃底贲门部黏膜不均匀增厚,考虑为恶性肿瘤,并存在胃小弯侧多发淋巴结转移的可能性。2024年11月17日后,患者吞咽困难症状加重,遂于2024年11月26日转诊至南方医科大学珠江医院,门诊以食管胃结合部肿瘤收治。 展开更多
关键词 食管胃结合部腺癌 皮肤转移 免疫治疗 病例报告
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副干酪乳酪杆菌Glory LP16减轻抗生素引起小鼠肠道菌群失调并改善肠道屏障功能研究
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作者 马微微 吴金富 +2 位作者 赵伊阳 张紫薇 黄莉莉 《中国乳品工业》 北大核心 2025年第6期15-20,39,共7页
为探究不同剂量副干酪乳酪杆菌Glory LP16对小鼠肠道菌群紊乱的调节作用及内在机制,试验将60只BALB/c小鼠分成5组,第1周向小鼠灌胃盐酸林可霉素建立肠道菌群紊乱模型,第2周对模型小鼠进行副干酪乳酪杆菌Glory LP16干预治疗,干预结束后... 为探究不同剂量副干酪乳酪杆菌Glory LP16对小鼠肠道菌群紊乱的调节作用及内在机制,试验将60只BALB/c小鼠分成5组,第1周向小鼠灌胃盐酸林可霉素建立肠道菌群紊乱模型,第2周对模型小鼠进行副干酪乳酪杆菌Glory LP16干预治疗,干预结束后检测小鼠粪便中肠球菌、大肠杆菌、乳酸杆菌、双歧杆菌含量,评价小鼠肠道微生物定植抗力,同时收集各组小鼠血液、结肠组织进行肠道通透性、组织病理学、肠道屏障分析。结果表明,相比于模型组,副干酪乳酪杆菌Glory LP16治疗组不同程度改善了盐酸林可霉素诱导的体质量减少、肠道组织结构损伤,促进乳酸杆菌和双歧杆菌等有益菌的丰度提高,并抑制肠球菌和大肠杆菌等有害菌定植,高剂量组小鼠的肠道菌群物种组成均趋向于空白组水平。副干酪乳酪杆菌Glory LP16可调节肠道菌群结构,改善由抗生素导致的肠道菌群紊乱状况。 展开更多
关键词 副干酪乳酪杆菌Glory LP16 肠道菌群 紧密连接蛋白 肠道通透性
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近日节律基因Clock调控小鼠肠道菌群及肠道结构影响NAFLD的发生发展
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作者 陈晓惠 任欣欣 +4 位作者 雷艳 李敏倩 王芳 王蓓 杨淑红 《兰州大学学报(自然科学版)》 北大核心 2025年第1期109-117,共9页
构建肝-肠轴部位敲低Clock基因的C57BL/6小鼠,通过西方饮食喂养建立非酒精性脂肪肝疾病(NAFLD)型,检测Clock基因对肝脏和肠道组织的影响,通过16S rDNA测序分析小鼠肠道微生物组学变化.结果显示,敲低Clock基因会加剧小鼠NAFLD症状,表现... 构建肝-肠轴部位敲低Clock基因的C57BL/6小鼠,通过西方饮食喂养建立非酒精性脂肪肝疾病(NAFLD)型,检测Clock基因对肝脏和肠道组织的影响,通过16S rDNA测序分析小鼠肠道微生物组学变化.结果显示,敲低Clock基因会加剧小鼠NAFLD症状,表现为肝脏脂肪沉积增多和纤维化明显;改变肠道组织结构,表现为肠道绒毛高度降低,杯状细胞数目减少,且肠道紧密连接蛋白质TJP1和OCCLUDIN表达水平下调.Clock基因会改变小鼠肠道微生物组成,可能通过影响NAFLD小鼠肠道组织结构及肠道菌群参与NAFLD的发生发展. 展开更多
关键词 非酒精性脂肪肝疾病 CLOCK基因 肠道菌群 肠道紧密连接
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Semi-floating gate ferroelectric phototransistor optoelectronic integrated devices
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作者 SHANG Jia-Le CHEN Yan +7 位作者 YAN Hao-Ran DI Yun-Xiang HUANG Xin-Ning LIN Tie MENG Xiang-Jian WANG Xu-Dong CHU Jun-Hao WANG Jian-Lu 《红外与毫米波学报》 北大核心 2025年第1期52-58,共7页
In the realm of optoelectronics,photodetectors play pivotal roles,with applications spanning from high-speed data communication to precise environmental sensing.Despite the advancements,conventional photodetectors gra... In the realm of optoelectronics,photodetectors play pivotal roles,with applications spanning from high-speed data communication to precise environmental sensing.Despite the advancements,conventional photodetectors grapple with challenges with response speed and dark current.In this study,we present a photodetector based on a lateral MoTe_(2)p-n junction,defined by a semi-floating ferroelectric gate.The strong ferroelectric fields and the depletion region of the p-n junction in the device are notably compact,which diminish the carrier transit time,thereby enhancing the speed of the photoelectric response.The non-volatile MoTe_(2)homojunction,under the influence of external gate voltage pulses,can alter the orientation of the intrinsic electric field within the junction.As a photovoltaic detector,it achieves an ultra-low dark current of 20 pA,and a fast photo response of 2μs.The spectral response is extended to the shortwave infrared range at 1550 nm.Furthermore,a logic computing system with light/no light as binary input is designed to convert the current signal to the voltage output.This research not only underscores the versatility of 2D materials in the realm of sophisticated photodetector design but also heralds new avenues for their application in energy-efficient,high-performance optoelectronic devices. 展开更多
关键词 PHOTODETECTORS p-n junction ferroelectric field high-speed photodetector
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可见光催化下负载型改性Ag_(3)PO_(4)处理染料废水的研究进展
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作者 班福忱 魏煜 《水处理技术》 北大核心 2025年第7期1-6,13,共7页
综述了可见光催化下负载型改性Ag_(3)PO_(4)处理染料废水的研究进展。Ag_(3)PO_(4)催化剂具有较高的量子产率,但是由于光腐蚀严重、能隙带宽度、光谱响应范围、及光生电子-空穴寿命短等问题制约着催化剂的催化效率,为此本文重点阐述了Ag... 综述了可见光催化下负载型改性Ag_(3)PO_(4)处理染料废水的研究进展。Ag_(3)PO_(4)催化剂具有较高的量子产率,但是由于光腐蚀严重、能隙带宽度、光谱响应范围、及光生电子-空穴寿命短等问题制约着催化剂的催化效率,为此本文重点阐述了Ag_(3)PO_(4)作为一种光催化剂在染料废水处理中的应用,并探讨了负载型改性Ag_(3)PO_(4)在催化活性、稳定性和可重复性方面的优势。总结了近年来关于负载型改性Ag_(3)PO_(4)在染料废水处理中的研究进展,包括不同负载物、改性方法和反应条件对催化性能的影响。最后对未来研究方向进行展望,提出了进一步优化负载型改性Ag_(3)PO_(4)催化剂结构、提高其光催化活性和稳定性的建议,以期为染料废水治理技术的发展提供参考。 展开更多
关键词 光催化 异质结 印染废水 改性Ag_(3)PO_(4) 掺杂
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