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Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

在光纤无线电技术中,通过光外差产生毫米波具有结构简单、成本低的特点,但中心站一般需要使用相干光源。文章提出了一种改进的光外差法,系统分析和仿真试验表明,该方法不仅可以避免使用相干光源,而且中心站和无线终端都无需配备毫米波本振。同时中心站采用单边带的信号调制,还可以有效降低光纤色散引起的毫米波信号的衰落。

研究了 2，7-二甲基-2，4，6-辛三烯-1，8-二醛并联合成工艺，以4-乙酰氧基-2-甲基-2-丁烯醛为原料，经醛基保护、酯交换、氧化合成3-（5，5-二甲基-1，3-二噁烷-2-基）-2-丁烯醛；采用氯化亚铜、1-氧自由基-2，2，6，6-四甲基-4-羟基-哌啶催化氧化2-（3-羟基-1-甲基-1-丙烯基）-5，5-二甲基-1，3-二噁烷合成3-（5，5-二甲基-1，3-二噁烷-2-基）-2-丁烯醛；2-（3-羟基-1-甲基-1-丙烯基）-5，5-二甲基-1，3-二噁烷经过氯化合成2-（3-氯-1-甲基-1-丙烯基）-5，5-二甲基-1,3-二噁烷；3-（5，5-二甲基-1，3-二噁烷-2-基）-2-丁烯醛、2-（3-氯-1-甲基-1-丙烯基）-5，5-二甲基-1，3-二噁烷与亚磷酸三乙酯一锅法工艺制得十碳三烯双醛，以五碳醛作为基准物，并联工艺总收率为48%.

文章介绍了所组建的全氟树脂塑料光纤千兆以太网的设计方案、设备选择及安装,给出了网络的性能测试数据,分析了全氟树脂塑料光纤及其所构筑的千兆以太网存在的问题,分析了全氟树脂塑料光纤千兆以太网的应用前景,提出了我国应加紧该领域研究的建议。

塑料光纤（POF）技术日益成熟,其产品在通信领域的应用量不断扩大。文章简述了POF的性能,探讨了各种POF在楼宇布线中应用的可行性,总结了当前楼宇布线标准和POF标准的发展概况,最后分析了当前布线标准所存在的缺陷和POF标准制定的紧迫性。

文章介绍了利用不同占空比实现信道复用的新型复用技术,即DCDM（占空比复用）技术,分析了其复用与解复用的原理,并利用MATLAB软件设计了DCDM系统的解复用器。为了验证DCDM的可行性,采用Optisystem与MATLAB软件的联合仿真,设计了基于DCDM 3路用户的光纤传输系统,仿真验证了系统的可行性。

文章提出了两种利用SOA（半导体光放大器）的XGM（交叉增益调制）和FBG（光纤布拉格光栅）光学生成对称型UWB（超宽带）信号的新方法。分析了该方法的工作原理并进行了仿真实验,分别得到了符合FCC（美国联邦通信委员会）标准的中心频率为5.35 GHz、相对带宽为114%以及中心频率为4.7 GHz、相对带宽为132%的对称型UWB信号,仿真结果验证了该方法的可行性。文章还分析了这两种方法存在的问题。

文章设计了一个基于频率间插复用的DWDM-ROF（密集波分复用-光载无线）系统,使每个信道载波与边带之间的空闲频段得到利用,从而提高了DWDM-ROF系统的频谱利用率。同时,为该系统设计了一种基于FBG（光纤布拉格光栅）的新颖的解复用器。数据传输的仿真实验不仅验证了该方法的可行性,还显示出了该系统具有良好的抗信道串扰能力。

描述了光包交换节点的结构 ,分析了网络的物理和逻辑的可行性 .介绍了一个由 40个网络节点组成的节点流量达 1 60 Gbit/s的物理网络 .网络能提供较好的服务质量 （包丢失率和包传输延迟 ）并兼容多种业务 .这一结果为基于全光包交换技术的灵活性网络的研究铺平了道路

Copyright of Water Conservancy & Electric Power Technology & Application is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solving partial differential equations plays a vital role of numerical analysis in scientific and engineering fields such as computational fluid dynamics. Due to the multi-scale nature of physics and sensitivity to the quality of the discrete mesh, traditional numerical methods often require complex human-computer interaction and expensive meshing overhead, which limit their application to many realtime simulation and optimal design problems. This paper proposes an improved neural network-based methodforsolvingpartialdiferentialequations, named TaylorPINN. It utilizes the universal approximation theorem of neural networks and the function-fitting capability of Taylor formula, and provides a mesh-freenumericalsolvingprocess. Numerical experimental resultson Helmholtz, Klein-Gordon, and Navier-Stokesequations demonstrate that Taylor PINN is able to approximate the underlying mapping relationsbetweenthecoordinateinputsandquantitiesofinterest, yielding an a ccurateprediction result. Comparedwiththe widely used physics-informed neural network method, TaylorPINN improves the prediction accuracy by a factor of 3~20x across different numerical problems. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals Engineering is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geography & Geographic Information Science is the property of Geography & Geo-Information Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Preeclampsia is a unique syndrome of pregnancy involving multiple organ systems, with no final conclusion in its pathogenesis. Endothelial dysfunction is a mechanism that has been widely used in basic research. Therefore, NG-nitro-L-arginine methyl ester was used in this study for preeclampsia modeling, followed by treatment with metformin. OBJECTIVE: To establish the model of preeclampsia in rats by intraperitoneal injection of NG-nitro-L-arginine methyl ester, and to explore the effects of metformin on preeclampsia and cognitive function in rats. METHODS: Pregnant rats were randomly divided into control group, model group, and metformin group. The model group was intraperitoneally injected with NG-nitro-L-arginine methyl ester in the middle and late pregnancy, and the metformin group was intraperitoneally injected with the same dose of NG-nitro-L-arginine methyl ester and metformin in the middle and late pregnancy. Body mass of each pregnant rat was recorded and corresponding drug dose was calculated every day. Caudal artery blood pressure was measured, and soluble endothelin and placental growth factor levels were quantified on day 19 of gestation and on days 10 and 30 after delivery. On the 19th day of gestation, urine was collected for 24 hours for urinary albumin and creatinine quantification. The Morris water maze test was conducted on the 10th and 30th days after delivery to obtain the escape latency, number of platform crossings and the average time spent in the target site where the platform was located. RESULTS AND CONCLUSION: Intraperitoneal injection of NG-nitro-L-arginine methyl ester could successfully establish the preeclampsia model in rats, resulting in hypertension, proteinuria and intrauterine growth restriction and endothelial dysfunction. Metformin could improve the preeclampsia-like performance induced by NG-nitro-L-arginine methyl ester. NG-nitro-L-arginine methyl ester-induced preeclampsia rats presented with impaired cognitive function 10 and 30 days after delivery, and metformin treatment could improve the above performance to a certain extent. Therefore, metformin has certain potential in the treatment and prevention of preeclampsia, and its mechanism of action needs to be further studied. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Medical Education Technology is the property of China Medical Education Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian Ocean University is the property of Journal of Dalian Ocean University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Tropical Meteorology (1004-4965) is the property of Guangzhou Institute of Tropical & Oceanic Meteorology, China Meteorological Administration and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

设计了一种结构简单、成本低的TW-EDFL（三波长掺铒光纤激光器）,其输出波长分别为1 530、1 540和1 550nm,实现了1.5mW的稳定输出功率。研究了EDF（掺铒光纤）长度和泵浦功率与输出功率的关系,得到最佳EDF长度为4.15m、最佳泵浦功率为200mW的结论。在结构中加入3个VOA（可变光衰减器）,运用增益均衡的方法来平衡谐振腔内3路信号光的增益和损耗,避免了EDF在室温下的模式竞争效应。

Objective To determine the effect of the Neuregulin-1 and its receptor ErbB4（NRG1-ErbB4） polymorphisms on focal epilepsy. Methods Three single nucleotide polymorphisms （SNPs） of NRG1 gene and three single nucleotide polymorphisms （SNPs） of ErbB4 gene in 70 patients with focal epilepsy and 64 healthy persons were analyzed by the PCR-SnapShot genotyping methods.The samples were all from the First Affiliated Hospital of Kunming Medical University from March to July, 2020. Results It was found that focal epilepsy was correlated with polymorphism of NRG1 （SNP rs35753505, T > C）, the distribution of genotype （P = 0.007） and allele （P = 0.005） of NRG1 （SNP rs35753505, T > C） was statistically significant （P < 0.005）. Meanwhile, ErbB4 gene polymorphisms of NRG1 downstream receptors was analyzed firstly, and two SNPs was found to be associated with focal epilepsy, ErbB4 SNP（rs839523, P = 0.026） and its allele （P = 0.013）, ErbB4 SNP（rs707284, P = 0.038） and its allele （P = 0.018）. However, no statistically significant association was found between NRG1（rs6994992, rs62510682）, ErbB4（rs7598440） polymorphisms and focal epilepsy. Conlusions The susceptibility of focal epilepsy carrying NRG1（SNP, rs35753505） and ErbB4（rs839523, rs707284） mutation homozygous has increased. NRG1-ErbB4 polymorphisms might play an important role together in the susceptibility to partial epilepsy. [ABSTRACT FROM AUTHOR]

【目的】 探讨肿瘤坏死因子-α(TNF-α)?白细胞介素1β(IL-1β)?基质金属蛋白酶-3(MMP-3)?基质金属蛋白酶-9(MMP-9)和基质金属蛋白酶抑制剂-1(TIMP-1)在大鼠脑缺血再灌注后的动态变化及特点,阐明TNF-α?IL-1β在脑缺血大鼠MMP和TIMP-1引起脑损伤中的作用?【方法】 雄性SD大鼠56只随机分为假手术组和缺血2 h再灌注6?12?24?48?72 h和7 d组?运用线栓法复制大鼠局灶性脑缺血再灌注模型,采用ELISA法测定脑组织和血清TNF-α和IL-1β含量,及脑组织中MMP-3?MMP-9和TIMP-1的含量?【结果】 与假手术组比较,血清和脑组织TNF-α和IL-1β含量于缺血再灌注6 h明显增加(4.38 ± 0.73 vs 2.63 ± 0.14?5.28 ± 0.71 vs 3.46 ± 0.47;22.34 ± 3.56 vs 12.13 ± 4.26?9.56 ± 0.85 vs 4.23 ± 0.83; P < 0.05),12 h达到高峰,随后各时间点表达开始下降,至7 d与假手术组比较无明显差别?脑组织中MMP-3?MMP-9含量于再灌注6 h开始升高,24 h明显升高(P < 0.05),48 h达高峰,随后逐渐下降,至再灌注7 d与假手术组比较无统计学意义,而脑组织中TIMP-1含量在再灌注各时间点均低于假手术组(P < 0.05)?且血清和脑组织中TNF-α和IL-1β含量与MMP-3?MMP-9的含量呈明显正相关(P < 0.05),与TIMP-1含量呈负相关(P < 0.05)?【结论】 MMP-3?MMP-9在脑缺血大鼠缺血再灌注早期水平即升高,提示MMP-3和MMP-9在脑缺血再灌注的发病过程中起着重要的作用,炎症因子TNF-α和IL-1β可通过促进脑组织中MMP-3?MMP-9的生成,抑制TIMP-1的生成,进一步加重缺血后脑损伤?

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concave corner structure has excellent vibration and noise reduction characteristics to effectively attenuate the structural vibration response, honeycomb structure with excellent mechanical properties has been more commonly used in engineering, so the composite structure of concave corner honeycomb has attracted the attention of scholars. A novel phononic crystal model was created using the inner concave honeycomb structure' s fractal design. Based on the finite element method, the fractal concave angle honeycomb structure was analyzed to calculate the energy band structure and vibration transmission characteristics, as well as to examine the negative Poisson ratio characteristics of the structure and the effect of the structural fractal on the vibration band gap. By varying parameters such as wall thickness and the angle of the inner concavity, filling the steel at the apex of the fractal structure can provide better suppression of certain frequency bands of vibration. The results show that the fractal structure still has negative Poisson ratio characteristics, the fractal structure produces a wider band gap in the second-order structure, the increase in wall thickness and concave angle causes the structural vibration band gap to shift to the high-frequency region, the filled steel causes the band gap to widen. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)