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基于外部气相沉积的S+C+L波段低色散斜率大有效面积非零色散位移光纤的设计与制备
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作者 查健江 王元达 +3 位作者 何学荣 侯伟 王敬胜 文建湘 《光子学报》 EI CAS CSCD 北大核心 2024年第2期52-63,共12页
针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第... 针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第一芯层的半径比,探究了其对光纤衰减、色散斜率和有效面积等参数的影响。研究发现,当第一芯层的相对折射率逐渐增大且第二芯层与第一芯层半径比逐渐减小时,零色散波长和有效面积逐渐减小。当第一芯层的相对折射率在0.52%~0.53%,芯层半径比在2.6~2.7时,光纤的有效面积接近70μm^(2),零色散波长在1420 nm附近,在1550 nm波段的色散系数大于8 ps·nm^(-1)·km^(-1),色散斜率为0.059 ps·nm^(-2)·km^(-1),可以较好地抑制传输过程中光非线性效应,满足长途干线网与城域网的使用要求。 展开更多
关键词 光纤通信 非零色散位移光纤 外部气相沉积工艺 S%PlUS%C%PlUS%l波段 低色散斜率 大有效面积 波分复用
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基于BiLSTM-Attention的F_(10.7)指数预测模型与中国自主数据集的应用
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作者 闫帅楠 李雪宝 +7 位作者 董亮 黄文耿 王晶 闫鹏朝 娄恒瑞 黄徐胜 李哲 郑艳芳 《空间科学学报》 CAS CSCD 北大核心 2024年第2期251-261,共11页
F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM... F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM)基础上融入注意力机制(Attention),提出了一种基于BiLSTM-Attention的F_(10.7)预报模型.在加拿大DRAO数据集上其平均绝对误差(MAE)为5.38,平均绝对百分比误差(MAPE)控制在5%以内,相关系数(R)高达0.987,与其他RNN模型相比拥有优越的预测性能.针对中国廊坊L&S望远镜观测的F_(10.7)数据集,提出了一种转换平均校准(Conversion Average Calibration,CAC)方法进行数据预处理,处理后的数据与DRAO数据集具有较高的相关性.基于该数据集对比分析了RNN系列模型的预报效果,实验结果表明,BiLSTM-Attention和BiLSTM两种模型在预测F_(10.7)指数方面具有较好的优势,表现出较好的预测性能和稳定性. 展开更多
关键词 F_(10.7)预报 双向长短时记忆网络 注意力机制 l&S数据集
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基于理性扩展热力学的L-S热声弹性理论框架
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作者 李元燮 刘财 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第2期655-687,共33页
本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrang... 本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrange描述和Euler描述,以及3种不同的状态和构形,同时针对热声弹性情况定义了两类从自然状态到初始状态的转变过程;在力学与热力学部分,给出了质量守恒定律、动量守恒定律、角动量守恒定律、能量守恒定律以及熵产不等式,从而引出经典不可逆热力学的局限性;在本构方程与演化方程部分,介绍了扩展不可逆热力学原理,并基于理性扩展热力学流程,推导了从自然状态到初始状态、从初始状态到最终状态的热声弹性本构方程与演化方程,将热流作为本构自变量并考虑了热流与应变和温度的相关性;在最后一部分给出了基本场方程的运动方程形式和适用于数值模拟的一阶速度-应力-热流-温度微分方程。 展开更多
关键词 l-S理论 热弹性 声弹性 连续介质力学 理性扩展热力学
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Unveiling DNA methylation in Alzheimer’s disease:a review of array-based human brain studies
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作者 Victoria Cunha Alves Eva Carro Joana Figueiro-Silva 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2365-2376,共12页
The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centere... The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centered studies that investigate whole genome DNA methylation in Alzheimer’s disease neuropathology.The examination of various brain regions reveals distinctive DNA methylation patterns that associate with the Braak stage and Alzheimer’s disease progression.The entorhinal cortex emerges as a focal point due to its early histological alterations and subsequent impact on downstream regions like the hippocampus.Notably,ANK1 hypermethylation,a protein implicated in neurofibrillary tangle formation,was recurrently identified in the entorhinal cortex.Further,the middle temporal gyrus and prefrontal cortex were shown to exhibit significant hypermethylation of genes like HOXA3,RHBDF2,and MCF2L,potentially influencing neuroinflammatory processes.The complex role of BIN1 in late-onset Alzheimer’s disease is underscored by its association with altered methylation patterns.Despite the disparities across studies,these findings highlight the intricate interplay between epigenetic modifications and Alzheimer’s disease pathology.Future research efforts should address methodological variations,incorporate diverse cohorts,and consider environmental factors to unravel the nuanced epigenetic landscape underlying Alzheimer’s disease progression. 展开更多
关键词 Alzheimer’s disease ANK1 BIN1 DNA methylation epigenome-wide association studies HOXA3 MCF2l RHBDF2
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Prognostic significance and relationship of SMAD3 phosphoisoforms and VEGFR-1 in gastric cancer:A clinicopathological study
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作者 Shi-Lin Lv Pei Guo +3 位作者 Jun-Rong Zou Ren-Sheng Chen Ling-Yu Luo De-Qiang Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期118-132,共15页
BACKGROUND The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer metastasis.SMAD3 phosphorylation is a crucial prognostic marker in gastric cancer.AIM To determine the prognostic value... BACKGROUND The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer metastasis.SMAD3 phosphorylation is a crucial prognostic marker in gastric cancer.AIM To determine the prognostic value and relationship of SMAD3 phospho-isoforms and VEGFR-1 in gastric cancer.METHODS This was a single-center observational study which enrolled 98 gastric cancer patients and 82 adjacent normal gastric tissues from patients aged 32-84 years(median age 65)between July 2006 and April 2007.Patients were followed up until death or the study ended(median follow-up duration of 28.5 mo).The samples were used to generate tissue microarrays(TMAs)for immunohistochemical(IHC)staining.The expressions of TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 in gastric cancer(GC)tumor tissue and normal tissue were measured by IHC staining using TMAs obtained from 98 GC patients.Prognosis and survival information of the patients was recorded by Outdo Biotech from May 2007 to July 2015.The relationship between TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 protein expression levels was analyzed using Pearson's correlation coefficient.The relationship between protein expression levels and clinicopathological parameters was analyzed using the Chi-squared test.A survival curve was generated using the Kaplan-Meier survival analysis.RESULTS TGFβ-1 and VEGFR-1 expression was significantly upregulated in gastric cancer tissue compared to adjacent noncancerous tissue.The positive expression of phosphorylated isoforms of Smad3 varied depending on the phosphorylation site[pSMAD3C(S423/425):51.0%and pSMAD3L(S204):31.6%].High expression of pSMAD-3L(S204)was significantly correlated with larger tumors(P=0.038)and later N stages(P=0.035).Additionally,high expression of VEGFR-1 was closely correlated with tumor size(P=0.015)and pathological grading(P=0.013).High expression of both pSMAD3L(S204)and VEGFR-1 was associated with unfavorable outcomes in terms of overall survival(OS).Multivariate analysis indicated that high expression of pSMAD3L(S204)and VEGFR-1 were independent risk factors for prognosis in GC patients.VEGFR-1 protein expression was correlated with TGF-β1(r=0.220,P=0.029),pSMAD3C(S423/425)(r=0.302,P=0.002),and pSMAD3L(S204)(r=0.201,P=0.047),respectively.Simultaneous overexpression of pSMAD3L(S204)and VEGFR-1 was associated with poor OS in gastric cancer patients.CONCLUSION Co-upregulation of pSMAD3L(S204)and VEGFR-1 can serve as a predictive marker for poor gastric cancer prognosis,and pSMAD3L(204)may be involved in enhanced gastric cancer metastasis in a VEGFR-1-dependent manner. 展开更多
关键词 Gastric cancer pSMAD3l(S204) pSMAD3C(S423/425) SURVIVAl Transforming growth factor-β1 VEGFR-1
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On the Range of Action of Adult Culex pipiens s.l.
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作者 Maria da Conceição Proença Maria Teresa Rebelo 《Journal of Biosciences and Medicines》 2024年第3期113-121,共9页
Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans... Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures. 展开更多
关键词 Mosquito Fly Distance Vector-Borne Diseases Culex pipiens s.l. Geographic Information Systems
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Accurate Diagnosis of SARS-CoV-2 JN.1 by Sanger Sequencing of Receptor-Binding Domain Is Needed for Clinical Evaluation of Its Immune Evasion
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作者 Sin Hang Lee 《Journal of Biosciences and Medicines》 2024年第4期69-78,共10页
Background: Omicron JN.1 has become the dominant SARS-CoV-2 variant in recent months. JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation... Background: Omicron JN.1 has become the dominant SARS-CoV-2 variant in recent months. JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation. The immune evasion capability of JN.1 is a subject of scientific investigation. The US CDC used SGTF of TaqPath COVID-19 Combo Kit RT-qPCR as proxy indicator of JN.1 infections for evaluation of the effectiveness of updated monovalent XBB.1.5 COVID-19 vaccines against JN.1 and recommended that all persons aged ≥ 6 months should receive an updated COVID-19 vaccine dose. Objective: Recommend Sanger sequencing instead of proxy indicator to diagnose JN.1 infections to generate the data based on which guidelines are made to direct vaccination policies. Methods: The RNA in nasopharyngeal swab specimens from patients with clinical respiratory infection was subjected to nested RT-PCR, targeting a 398-base segment of the N-gene and a 445-base segment of the RBD of SARS-CoV-2 for amplification. The nested PCR amplicons were sequenced. The DNA sequences were analyzed for amino acid mutations. Results: The N-gene sequence showed R203K, G204R and Q229K, the 3 mutations associated with Omicron BA.2.86 (+JN.1). The RBD sequence showed 24 of the 26 known amino acid mutations, including the hallmark L455S mutation for JN.1 and the V483del for BA.2.86 lineage. Conclusions: Sanger sequencing of a 445-base segment of the SARS-CoV-2 RBD is useful for accurate determination of emerging variants. The CDC may consider using Sanger sequencing of the RBD to diagnose JN.1 infections for statistical analysis in making vaccination policies. 展开更多
关键词 Omicron JN.1 SARS-CoV-2 Sanger Sequencing RBD l455S Mutation Immune Evasion Vaccination Policies CDC
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有限元分析对骨质疏松条件下L5/S1斜外侧椎间融合与两种后路固定的生物力学研究
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作者 马玉轩 张涛 +3 位作者 杨成伟 高杰 高红亮 李松凯 《宁夏医科大学学报》 2024年第6期627-633,共7页
目的评估在骨质疏松条件下,行L5/S1节段斜外侧椎间融合术(oblique lateral interbody fusion at L5/S1,OLIF51)及其联合双侧皮质骨轨迹螺钉(cortical bone trajectory screw,CBT)和双侧椎弓根螺钉(bilateral pedicle screw,BPS)的生物... 目的评估在骨质疏松条件下,行L5/S1节段斜外侧椎间融合术(oblique lateral interbody fusion at L5/S1,OLIF51)及其联合双侧皮质骨轨迹螺钉(cortical bone trajectory screw,CBT)和双侧椎弓根螺钉(bilateral pedicle screw,BPS)的生物力学性能。方法招募1名健康青年男性作为志愿者,获得其腰骶椎三维CT数据,在有限元分析软件中完成L4~S1三维模型,采用前路钛板(titanium plate,TP)固定的OLIF51手术模型、OLIF51+CBT和OLIF51+BPS手术模型的构建,分别命名为A、B、C、D模型。通过赋值、设定条件、施加载荷,分析不同条件下的生物力学特性。结果顺利完成4种有限元模型的构建。4种模型在所有运动中的平均活动度(range of motion,ROM)变化趋势为A模型>B模型>C模型>D模型;其中,与A模型相比,B模型降幅为84.21%~94.42%,C模型降幅为88.12%~96.40%,D模型降幅为90.07%~96.49%(P均<0.05);与B模型相比,C模型降幅为7.41%~52.38%,D模型降幅为27.78%~58.33%(P均<0.05)。3种手术模型在所有运动中的融合器(Cage)平均最大应力变化趋势为B模型>C模型>D模型;其中,与B模型相比,C模型降幅为12.89%~57.62%,D模型降幅为36.43%~73.11%;D模型和C模型相比,除左侧弯外差异均有统计学意义(P均<0.05);D模型降幅为21.83%~37.67%。3种手术模型在所有运动中的内固定平均最大应力变化趋势为B模型>C模型>D模型;与B模型相比,C模型降幅为3.55%~65.47%,D模型降幅为18.58%~84.41%;CBT应力大于BPS应力(P<0.05)。结论在OLIF51手术中,补充后路内固定可以增强融合节段的稳定性并减轻TP上的应力。不建议对骨质疏松症患者单独进行OLIF51手术,使用BPS辅助固定可达到最佳生物力学特性。接受CBT辅助内固定的患者术后需要佩戴支具,并尽量避免融合部位的右侧弯曲运动。 展开更多
关键词 l5/S1节段斜外侧椎间融合术 稳定性 内固定 有限元分析
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L型氨基酸转运蛋白1的表达对非霍奇金淋巴瘤临床病理特征和预后的影响
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作者 赵志芳 郝秀君 +3 位作者 杨艳敏 徐伟格 张云晓 原现华 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第2期434-438,共5页
目的:检测非霍奇金淋巴瘤(NHL)组织中L型氨基酸转运蛋白1(LAT1)的表达,分析LAT1对患者临床病理特征和预后的影响。方法:收集2017年1月至2019年4月在本院接受治疗的NHL患者92例,免疫组织化学检测NHL组织中LAT1的表达,比较不同病理特征(... 目的:检测非霍奇金淋巴瘤(NHL)组织中L型氨基酸转运蛋白1(LAT1)的表达,分析LAT1对患者临床病理特征和预后的影响。方法:收集2017年1月至2019年4月在本院接受治疗的NHL患者92例,免疫组织化学检测NHL组织中LAT1的表达,比较不同病理特征(包括性别、Ann Arbor分期、结外浸润、Ki-67)患者组间LAT1的表达差异,单因素和多因素Cox回归分析影响患者死亡的危险因素,受试者工作曲线(ROC)检测NHL组织中LAT1阳性细胞百分比对患者死亡的预测价值,分析LAT1阳性细胞百分比对患者生存率的影响。结果:LAT1在NHL组织中呈阳性表达,Ann Arbor分期III期和IV期组LAT1高表达率高于I期组,结外浸润组LAT1高表达率高于无结外浸润组,Ki-67阳性表达组LAT1高表达率高于阴性表达组,比较差异均有统计学意义(均P<0.05)。LAT1高表达组治疗3个疗程后的缓解率为70.7%,低于低表达组的91.2%,比较差异有统计学意义(P<0.05)。Ann Arbor分期III期、IV期、结外浸润、Ki-67阳性表达和LAT1表达增加(即LAT1阳性细胞比例评分≥2)为患者死亡的危险因素。LAT1阳性细胞百分比预测NHL死亡的截断值为45.6%,曲线下面积为0.905(95%CI:0.897-0.924)。LAT1高水平组(LAT1阳性细胞百分比≥45.6%)3年生存率为50.00%,低于LAT1低水平组的78.26%(P<0.05)。结论:LAT1在NHL组织中表达水平增加,影响患者的肿瘤分期和结外浸润,是患者死亡的危险因素。 展开更多
关键词 非霍奇金淋巴瘤 l型氨基酸转运蛋白1 生存率
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血清NSE,NF-L,s100β与急性脑梗死患者神经功能缺损程度的关系研究
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作者 贺显君 郑秀霞 赵明 《新疆医学》 2023年第7期783-786,共4页
目的探讨分析血清神经元特异性烯醇化醇(NSE),神经丝蛋白L(NF-L),s100β蛋白(s100β)水平与急性脑梗死患者神经功能缺损程度的相关性。方法选取2017年2月-2019年10月到商丘市第一人民医院治疗的急性脑梗死患者135例为研究组,选取同时期... 目的探讨分析血清神经元特异性烯醇化醇(NSE),神经丝蛋白L(NF-L),s100β蛋白(s100β)水平与急性脑梗死患者神经功能缺损程度的相关性。方法选取2017年2月-2019年10月到商丘市第一人民医院治疗的急性脑梗死患者135例为研究组,选取同时期入医院进行健康体检者122例为对照组,检测并对比2组血清中NSE,NF-L,s100β水平;神经功能缺损程度采用神经功能缺损(NIH Stroke Scale,NIHSS)量表评定,对比研究组中不同神经功能缺损程度的患者血清中NSE,NF-L,s100β水平;采用Pearson相关性分析法探讨研究组血清NSE,NF-L,s100β水平与急性脑梗死患者NIHSS评分的相关性。结果研究组患者血清NSE,NF-L,s100β水平高于对照组,差异均有统计学意义(P<0.05);研究组中度缺损组和重度缺损组血清NSE,NF-L,s100β水平高于轻度缺损伤组,且重度损伤组血清NSE,NF-L,s100β水平高于中度损伤组,差异均有统计学意义(P<0.05);血清NSE,NF-L,s100β水平与NIHSS评分呈正相关(r=0.909、0.823、0.730,P=0.000、0.000、0.000)。结论急性脑梗死患者血清NSE,NF-L,s100β水平存在异常变化,且血清NSE,NF-L,s100β水平与NIHSS评分呈显著正相关。 展开更多
关键词 神经元特异性烯醇化醇 神经丝蛋白l S100Β蛋白 急性脑梗死 神经功能缺损
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通信受限下T-S模糊网络控制系统L_(1)动态输出反馈控制
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作者 齐迹 李艳辉 《东北石油大学学报》 CAS 北大核心 2023年第6期101-111,I0007,I0008,共13页
针对通信受限的非线性网络控制系统,为兼顾系统性能和节约利用网络资源,引入事件触发通信机制(ETCM),利用时延建模方法和并行分布补偿(PDC)技术,将连续控制系统建模为一个采样数据误差依赖的非线性网络化系统模型;构建保守性低的时滞依... 针对通信受限的非线性网络控制系统,为兼顾系统性能和节约利用网络资源,引入事件触发通信机制(ETCM),利用时延建模方法和并行分布补偿(PDC)技术,将连续控制系统建模为一个采样数据误差依赖的非线性网络化系统模型;构建保守性低的时滞依赖和模糊基依赖的Lyapunov-Krasovskii泛函,给出增广系统稳定性和鲁棒性结果,得到鲁棒控制器存在的充分条件,提出一种基于线性矩阵不等式(LMIs)的事件触发参数,以及全局模糊L 1动态输出反馈控制器参数的协同设计方法。采用永磁同步电动机模型仿真验证,结果表明该设计方法可减少网络资源占用,达到闭环控制系统的性能要求。 展开更多
关键词 网络控制系统 T-S模糊模型 通信受限 l_(1)动态输出反馈控制 ETCM
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基于YOLOv5系列的火灾检测系统设计与实现 被引量:1
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作者 王文杰 田敏 +1 位作者 童宇 陈杰烜 《科技创新与应用》 2023年第12期39-44,共6页
火灾往往指的是失控的燃烧,对人们的财产及生命安全造成了严重的隐患。因此,就需要实时监测火灾是否发生,该文基于YOLOv5系列,包括YOLOv5s、YOLOv5m和YOLOv5l,对标注好的数据集分别利用3种权重文件进行模型训练,设计和实现能够实时监测... 火灾往往指的是失控的燃烧,对人们的财产及生命安全造成了严重的隐患。因此,就需要实时监测火灾是否发生,该文基于YOLOv5系列,包括YOLOv5s、YOLOv5m和YOLOv5l,对标注好的数据集分别利用3种权重文件进行模型训练,设计和实现能够实时监测火灾是否发生的系统。对上述3种不同的方法,进行比较,发现YOLOv5l的精确率、召回率和平均精度高于其他二者。 展开更多
关键词 YOlOv5s YOlOv5m YOlOv5l 火灾 检测系统
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1例EGFR L747S和L858R双突变肺腺癌患者的治疗
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作者 王腾飞 欧阳雯 +2 位作者 张俊红 张弓 谢丛华 《数理医药学杂志》 CAS 2023年第3期230-235,共6页
表皮生长因子受体(epidermal growth factor receptor,EGFR)突变中最常见的突变是外显子19缺失突变和外显子21 L858R突变,这两种突变都对EGFR酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)有非常好的响应性。然而,EGFR-... 表皮生长因子受体(epidermal growth factor receptor,EGFR)突变中最常见的突变是外显子19缺失突变和外显子21 L858R突变,这两种突变都对EGFR酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)有非常好的响应性。然而,EGFR-TKIs对罕见EGFR突变的疗效尚有争议。在治疗过程中,许多患者最终也会对EGFR-TKIs产生耐药性。此外,对于对奥希替尼产生耐药性的患者,特别是那些具有罕见或复杂突变的患者,仍然没有标准的治疗方案。本文介绍了1例具有EGFR L747S和L858R双突变的肺腺癌患者,该患者在出现奥希替尼耐药后接受帕博利珠单抗联合化疗治疗有效,且无疾病进展生存期为13个月。这是国内外首例在携带EGFR L747S和L858R双突变的肺腺癌患者对奥希替尼耐药之后使用帕博利珠单抗免疫治疗联合化疗的报道,本案例可为具有类似罕见突变患者的治疗提供参考。 展开更多
关键词 EGFR l747S突变 肺腺癌 奥希替尼 帕博利珠单抗
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不同跟踪方式下GPS L2C信号质量评估精度分析
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作者 代智辉 饶永南 郭瑶 《全球定位系统》 CSCD 2023年第5期56-63,共8页
卫星信号质量好坏会影响用户的使用性能,利用软件接收机的跟踪结果可以实现信号质量评估.GPS L2C信号的伪码是由CM码和CL码时分复用(time division multiplexing,TDM)组成,根据其信号特点可以使用不同的跟踪方式进行跟踪.针对不同跟踪... 卫星信号质量好坏会影响用户的使用性能,利用软件接收机的跟踪结果可以实现信号质量评估.GPS L2C信号的伪码是由CM码和CL码时分复用(time division multiplexing,TDM)组成,根据其信号特点可以使用不同的跟踪方式进行跟踪.针对不同跟踪方法对信号评估精度的影响,重点分析了信号一致性,信号的相关性能等指标.通过仿真信号分析和实测数据验证,结果表明:联合跟踪相比于单分量跟踪其评估精度更高,且各项指标的评估结果都优于单条支路的评估结果,使用联合跟踪会带来更小的测距误差. 展开更多
关键词 GPS l2C信号 跟踪 一致性 相关损失 S曲线偏差(SCB)
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温度对L360QS管线钢在H_(2)S/CO_(2)环境中腐蚀行为的影响
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作者 赵鹏 孟江 +3 位作者 葛鹏莉 严治 关芳艳 甘崇邑 《广州化工》 CAS 2023年第2期204-207,共4页
采用腐蚀失重实验和电化学实验探究40~60℃条件下L360QS钢试样的腐蚀规律。实验结果表明:在CO_(2)-H_(2)S-Cl^(-)共存体系中,随着温度的升高,腐蚀速率逐渐增大,腐蚀程度加剧,并出现点蚀。当温度低于50℃时,腐蚀并不严重,当温度高于50℃... 采用腐蚀失重实验和电化学实验探究40~60℃条件下L360QS钢试样的腐蚀规律。实验结果表明:在CO_(2)-H_(2)S-Cl^(-)共存体系中,随着温度的升高,腐蚀速率逐渐增大,腐蚀程度加剧,并出现点蚀。当温度低于50℃时,腐蚀并不严重,当温度高于50℃时,腐蚀产物膜致密性和完整度降低,易溶解破裂,出现“大阴极小阳极”现象,促进发生局部腐蚀。同时得到管线钢以CO_(2)腐蚀为主,H2S腐蚀为辅,均匀腐蚀主要受CO_(2)控制,点蚀由高浓度的Cl-造成。 展开更多
关键词 l360QS钢 温度 H_(2)S/CO_(2)腐蚀 点蚀
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叶面喷施S-烯丙基-L-半胱氨酸对水稻砷转运影响机制
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作者 郎耀臻 刘斌 +4 位作者 王常荣 刘仲齐 孔维勇 刘月敏 黄永春 《农业环境科学学报》 CAS CSCD 北大核心 2023年第7期1436-1443,共8页
膳食稻米是我国人群摄入高致癌风险无机砷(iAs)的主要来源,开发降低稻米砷(As)含量生产措施对保护人体健康具有重要意义。本文以我国南方主栽水稻品种“中早35”为试验材料,采用盆栽试验研究了开花期叶面喷施S-烯丙基-L-半胱氨酸(SAC)... 膳食稻米是我国人群摄入高致癌风险无机砷(iAs)的主要来源,开发降低稻米砷(As)含量生产措施对保护人体健康具有重要意义。本文以我国南方主栽水稻品种“中早35”为试验材料,采用盆栽试验研究了开花期叶面喷施S-烯丙基-L-半胱氨酸(SAC)对水稻籽粒和营养器官中总As含量的影响并揭示其潜在的分子机制。结果表明:当SAC喷施浓度达到0.2 mmol·L^(-1)时籽粒和根中总As含量分别显著降低42.3%和20.6%,但旗叶中总As含量显著增加了72.4%;荧光染色观察试验表明旗叶中H_(2)O_(2)含量显著降低,同时SOD和CAT酶活性分别显著升高61.8%和105.3%。喷施SAC后水稻顶端第一节中Lsi6转运子编码基因以及Lsi3转运子编码基因分别显著下调59.8%和36.3%,据此推测喷施SAC可能显著降低了水稻从通向旗叶膨大维管束流中卸载As^(Ⅲ)和向连接稻穗弥散维管束装载As^(Ⅲ)的能力,导致籽粒中总As含量显著降低而旗叶中总As含量显著升高。旗叶植物螯合素(PCs)合成酶OsPCS1和负责向细胞液泡中转运As^(Ⅲ)的OsABCC1转运子编码基因分别显著上调57.6%和61.0%,表明喷施SAC增加了旗叶合成PCs并向液泡中区隔As^(Ⅲ)的能力从而降低了叶片的As^(Ⅲ)胁迫。水稻根部Lsi1、Lsi2、Lsi3转运子编码基因分别显著下调了27.2%、23.8%、29.5%,表明水稻根部对As^(Ⅲ)的吸收、转运能力降低,同时可能也预示着As^(Ⅲ)向木质部导管中装载As^(Ⅲ)的能力降低。综上,喷施SAC通过调控As^(Ⅲ)转运子编码基因表达降低了水稻籽粒和根中总As含量,同时缓解了As胁迫。 展开更多
关键词 水稻 S-烯丙基-l-半胱氨酸 转运子 基因表达
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斜外侧腰椎椎间融合术在L5/S1水平的临床应用及手术入路选择
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作者 杨鹏超 徐勇 关邯峰 《骨科》 CAS 2023年第1期92-96,共5页
斜外侧腰椎椎间融合术(oblique lumbar interbody fusion,OLIF)是治疗腰椎退行性疾病的新型微创技术,其在缓解症状和纠正腰椎冠状位及矢状位平衡等方面有独特优势,与传统腰椎融合术相比,疗效确切且围术期并发症发生率较低。目前L2~L5水... 斜外侧腰椎椎间融合术(oblique lumbar interbody fusion,OLIF)是治疗腰椎退行性疾病的新型微创技术,其在缓解症状和纠正腰椎冠状位及矢状位平衡等方面有独特优势,与传统腰椎融合术相比,疗效确切且围术期并发症发生率较低。目前L2~L5水平相应解剖研究较为广泛,于左侧腰大肌和血管间行OLIF25手术技术成熟,风险可控。而L5/S1水平特殊的解剖结构使此技术应用受到限制,对比分析既往研究,进一步明确OLIF51的可行性、特点及优势,掌握相关的解剖学及影像学规律并结合病人术前影像资料评估,有利于指导OLIF51手术入路的选择及临床应用。 展开更多
关键词 斜外侧腰椎椎间融合术 l5/S1 髂血管 腰大肌
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Coaxial radiography guided puncture technique for percutaneous transforaminal endoscopic lumbar discectomy:A randomized control trial
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作者 Li-Ping Chen Bin-Song Wen +6 位作者 Heng Xu Zheng Lu Lai-Jun Yan Han Deng Hong-Bo Fu Hong-Jie Yuan Pei-Pei Hu 《World Journal of Clinical Cases》 SCIE 2023年第16期3802-3812,共11页
BACKGROUND The coaxial radiography-guided puncture technique(CR-PT)is a novel technique for endoscopic lumbar discectomy.As the X-ray beam and the puncturing needle are maintained in a parallel and coaxial direction,t... BACKGROUND The coaxial radiography-guided puncture technique(CR-PT)is a novel technique for endoscopic lumbar discectomy.As the X-ray beam and the puncturing needle are maintained in a parallel and coaxial direction,the X-ray beam can be used to guide the trajectory angle,facilitating the choice of the puncture site and providing real-time guidance.This puncture technique offers numerous advantages over the conventional anterior-posterior and lateral radiography-guided puncture technique(AP-PT),especially in cases of herniated lumbar discs with a hypertrophied transverse process or articular process,high iliac crest,and narrowed intervertebral foramen.AIM To confirm whether CR-PT is a superior approach to percutaneous transforaminal endoscopic lumbar discectomy compared to AP-PT.METHODS In this parallel,controlled,randomized clinical trial,herniated lumbar disc patients appointed to receive percutaneous endoscopic lumbar discectomy treatment were recruited from the Pain Management Department of the Affiliated Hospital of Xuzhou Medical University and Nantong Hospital of Traditional Chinese Medicine.Sixty-five participants were enrolled and divided into either a CR-PT group or an AP-PT group.The CR-PT group underwent CR-PT,and the AP-PT group underwent AP-PT.The number of fluoroscopies during puncturing,puncture duration(min),surgery duration(min),VAS score during puncturing,and puncture success rate were recorded.RESULTS Sixty-five participants were included,with 31 participants in the CR-PT group and 34 in the AP-PT group.One participant in the AP-PT group dropped out due to unsuccessful puncturing.The number of fluoroscopies[median(P25,P75)]was 12(11,14)in the CR-PT group vs 16(12,23)in the AP-PT group,while the puncture duration(mean±SD)was 20.42±5.78 vs 25.06±5.46,respectively.The VAS score was 3(2,4)in the CR-PT group vs 3(3,4)in the AP-PT group.Further subgroup analysis was performed,considering only the participants with L5/S1 segment herniation:9 patients underwent CR-PT,and 9 underwent AP-PT.The number of fluoroscopies was 11.56±0.88 vs 25.22±5.33;the puncture duration was 13.89±1.45 vs 28.89±3.76;the surgery duration was 105(99.5,120)vs 149(125,157.5);and the VAS score was 2.11±0.93 vs 3.89±0.6,respectively.All the above outcomes demonstrated statistical significance(P<0.05),favoring the CR-PT treatment.CONCLUSION CR-PT is a novel and effective technique.As opposed to conventional AP-PT,this technique significantly improves puncture accuracy,shortens puncture time and operation time,and reduces pain intensity during puncturing. 展开更多
关键词 Herniated lumbar disc COAXIAl PUNCTURE ANTERIOR-POSTERIOR l5/S1
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藤黄健骨胶囊在L,S椎间盘突出症术后中的应用及对血清β-内啡肽、IL-1β水平的影响
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作者 王振 萧锦瑜 +2 位作者 何永滔 郭炼锦 张勋梦 《中国医药导刊》 2023年第9期927-932,共6页
目的:探析藤黄健骨胶囊在L,S椎间盘突出症术后中的应用,及对血清β-内啡肽、白细胞介素-1β(IL-1β)水平的影响。方法:选择2021年1月至2022年3月我院收治的L,S椎间盘突出症患者110例作为研究对象,按随机数字表法均分为对照组和观察组,... 目的:探析藤黄健骨胶囊在L,S椎间盘突出症术后中的应用,及对血清β-内啡肽、白细胞介素-1β(IL-1β)水平的影响。方法:选择2021年1月至2022年3月我院收治的L,S椎间盘突出症患者110例作为研究对象,按随机数字表法均分为对照组和观察组,每组各55例。两组患者均接受UBE手术治疗,对照组予以常规西药治疗,观察组在对照组治疗的基础上加用藤黄健骨胶囊联合治疗。比较两组患者的疼痛视觉模拟(VAS)评分、血生化指标水平[β-内啡肽、IL-1β、超氧化物歧化酶(SOD)]、中医证候评分[主证总积分、次证总积分]、日本骨科学会评分(JOA)、Oswestry功能障碍指数(ODI)、临床疗效。结果:观察组患者治疗3 d、4周后,VAS评分降低幅度均大于对照组(P<0.05);治疗4周后,β-内啡肽、SOD检测值升高幅度均大于对照组(P<0.05),IL-1β检测值及主证总积分、次证总积分降低幅度均大于对照组(P<0.05);治疗4周后,JOA评分升高幅度大于对照组(P<0.05),ODI值降低幅度大于对照组(P<0.05);观察组患者总有效率高于对照组(P<0.05)。结论:藤黄健骨胶囊在L,S椎间盘突出症UBE术后治疗中,治疗效果更为理想,能缓解疼痛、减轻炎症反应,对缓解腰椎功能障碍、促进腰椎功能的恢复、提升临床疗效等均有重要作用。 展开更多
关键词 l S椎间盘突出症 单边双通道内镜 藤黄健骨胶囊 Β-内啡肽 白细胞介素 临床疗效
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Natural variations and geographical distributions of seed carotenoids and chlorophylls in 1167 Chinese soybean accessions
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作者 Berhane S.GEBREGZIABHER ZHANG Sheng-rui +7 位作者 Muhammad AZAM QI Jie Kwadwo G.AGYENIM-BOATENG FENG Yue LIU Yi-tian LI Jing LI Bin SUN Jun-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2632-2647,共16页
Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids a... Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry. 展开更多
关键词 accession type carotenoid CHlOROPHYll ECOREGION geographical distribution Pearson’s correlation soybean(Glycine max l.Merrill)
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