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Design of Digital Voice Storage and Playback System 预览
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作者 Xiaoling Ren Huiqiong Feng Kaida Shen 《当前的电子和电信》 2019年第1期22-30,共9页
The traditional tape voice recording and reproducing system has many limitations due to its large volume and inconvenient use in the use of electronic and information processing. This paper presents a compact, low-pow... The traditional tape voice recording and reproducing system has many limitations due to its large volume and inconvenient use in the use of electronic and information processing. This paper presents a compact, low-power digital voice storage and playback system will be able to replace it. The basic principle of digital voice storage and playback system is the digital control of voice recording and playback. Among them, the key technology is that in order to increase the voice storage time and improve the utilization of memory, the use of non-distortion compression algorithm to compress the voice signal and then stored in the playback and then decompression while the input voice signal Filtering to suppress noise and interference, thus ensuring the reliable quality of voice playback. The system uses three methods, namely data acquisition, straight sampling, sample sampling and self-similar incremental modulation to complete the storage and playback of voice signals 32.7s, 65.5s and 147.4s respectively. The front straight AGC controls the speech signal within the controllable range of the A / D converter to ensure that the voice signal is not distorted. Bandpass filter a reasonable range eff ectively, filters out-of-band noise and reduces aliasing distortion. Through the post-level compensation circuit on the output of the voice signal correction, playback voice clear. The system has the functions of automatic recording, manual recording, recording and playing time display and protection of voice signal after power failure. 展开更多
关键词 DIGITAL STORAGE PLAYBACK DIGITAL FILTERING sampling ANALOG / DIGITAL CONVERSION calibration
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A Novel Plus Type DVCC-Based Current-Mode Biquad 预览
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作者 Takao Tsukutani Noboru Yabuki 《电气工程:英文版》 2019年第2期51-53,共3页
This paper presents a novel current-mode biquad using only plus type DVCCs(differential voltage current conveyors).The circuit enables LP(low-pass),BP(band-pass),HP(high-pass),BS(band-stop)and AP(all-pass)responses by... This paper presents a novel current-mode biquad using only plus type DVCCs(differential voltage current conveyors).The circuit enables LP(low-pass),BP(band-pass),HP(high-pass),BS(band-stop)and AP(all-pass)responses by the selection and/or addition of the circuit currents with no component matching constraints.Moreover the circuit parametersω0 and Q can be set orthogonally adjusting the circuit components.An achievement example is given together with simulation results by PSPICE. 展开更多
关键词 ANALOG CIRCUITS biquad responses PLUS TYPE DVCCs
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核电厂发电机励磁调节器的技术改进与研究 预览
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作者 汪维 周倩 薛睿 《能源与节能》 2019年第5期48-52,共5页
简要阐述了核电厂励磁系统的发展现状,针对核电厂采用模拟式励磁调节器存在的一系列问题,分析了模拟式励磁调节器的不足,提出了用微机型励磁调节器整体替换的解决方案。
关键词 励磁系统 励磁调节器 模拟式 微机型
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Joint hybrid beamforming and power splitting design in millimeter-wave simultaneous wireless information and power transfer system
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作者 Bao Tiantian Wen Xiangming +2 位作者 Lu Zhaoming Chen Yawen Zheng Wei 《中国邮电高校学报:英文版》 EI CSCD 2019年第2期59-66,共8页
A joint hybrid beamforming and power splitting(JHBPS) design problem for simultaneous wireless information and power transfer(SWIPT) in millimeter-wave(mmWave) system is studied.The considered scenario is a multi-ante... A joint hybrid beamforming and power splitting(JHBPS) design problem for simultaneous wireless information and power transfer(SWIPT) in millimeter-wave(mmWave) system is studied.The considered scenario is a multi-antenna base station(BS) transfers information and energy simultaneously to multiple single-antenna receivers.BS adopts hybrid digital and analog beamforming architecture to reduce hardware costs.Receivers separate acquired signals with power splitters either for information decoding(ID) or energy harvesting(EH).The aim is minimizing total transmission power by joint design of hybrid beamforming and PS under ID and EH requirements.It is difficult to obtain the optimal hybrid beamformer directly since the analog beamformer and digital beamformer are multiplied.Therefore,a two-stage algorithm is proposed to solve the problem.In the first stage,the optimal beamformer and PS ratios are obtained by solving the joint transmission beamforming and PS design problem.In the second stage,the optimal beamformer is approximated with the product of analog beamformer and digital beamformer.The superiority of proposed algorithm over the existing algorithms is demonstrated through simulations.Moreover,the effectiveness of approximation algorithm is testified. 展开更多
关键词 SWIPT mmWave HYBRID ANALOG and digital BEAMFORMING
变频器对西门子PLC模拟量输入通道干扰故障解决实例 预览
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作者 刘伟杰 《变频器世界》 2019年第3期97-100,共4页
基于西门子PLC300模拟量模块接收现场仪表4~20mA信号,受到变频器MM420运行中存在的干扰问题,现场仪表进行校验台效验成标准的压力变送器送到现场进行安装调试,给PLC模拟量模块提供4-20mA信号反馈,变频器未启动的情况下根据五点效验0%、... 基于西门子PLC300模拟量模块接收现场仪表4~20mA信号,受到变频器MM420运行中存在的干扰问题,现场仪表进行校验台效验成标准的压力变送器送到现场进行安装调试,给PLC模拟量模块提供4-20mA信号反馈,变频器未启动的情况下根据五点效验0%、25%、50%、75%、100%液位均在正常测量范围,无明显大幅度波动。启动变频器运行后,现场仪表出现4-20mA电流不稳定、满量程漂移、液位出现大幅度波动。根据变频器出现的干扰问题,我们做出一系列的抵抗干扰和一些合理的解决措施。 展开更多
关键词 变频器 模拟量 干扰
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过载负荷下分叉血管的流动数值模拟 预览
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作者 鲍觅夏 周平 +1 位作者 郭凤 王佳 《中国组织工程研究》 CAS 北大核心 2019年第4期551-555,共5页
背景:人体对于过载负荷的大小具有一定的耐受极限,超过一定强度时会对人体造成损伤,过载对人体血管流动过程的影响是载人航天医学研究的一个重要课题。目的:针对典型的颈部动脉简化分叉三维血管模型进行了非常规重力载荷下的脉动流血管... 背景:人体对于过载负荷的大小具有一定的耐受极限,超过一定强度时会对人体造成损伤,过载对人体血管流动过程的影响是载人航天医学研究的一个重要课题。目的:针对典型的颈部动脉简化分叉三维血管模型进行了非常规重力载荷下的脉动流血管流动形态数值模拟分析。方法:根据人体的正常脉搏周期,计算过程设定0.85s为一个血液脉动供给周期。对于分叉血管(基于人体颈部动脉分支血管的几何特征进行刚性简化),假设正常状态下主血管与分支血管流量分配为7∶3。基于Fluent计算流体力学软件,通过在控制方程动量源项中添加重力载荷的方法(过载方向X+,过载大小为1G;过载方向Y+,过载大小为2G),分析重力过载效应对人体典型血管流动特征的影响。结果与结论:①获得了重力过载下的瞬态流场结构、壁面剪切应力的变化情况。由于受到Y+方向过载的影响,分叉血管在不同时刻在流速分布、回流区域大小、剪切应力分布上存在明显差异;②超重负荷效应下,分叉位置分支血管内壁面处形成了明显的分离区域且血液流量明显变大,造成主血管段内血液流量减少且发生严重的回流现象;③在超重负荷的影响下分支血管段壁面剪切应力明显大于主血管段壁面剪切应力。 展开更多
关键词 应力 物理 血流动力学 计算机 模拟 组织工程 重力过载 过载负荷分叉血管流动数值 剪切应力 数值模拟
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Versatile DVCC-Based Current-Mode IAFs without Parasitic Effects 预览
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作者 Takao Tsukutani Noboru Yabuki 《电气工程:英文版》 2019年第1期19-22,共4页
This paper introduces current-mode IAFs (inverse active filters) employing DVCCs (differential voltage current conveyors) and grounded passive elements without the parasitic effects. The IAFs enable ILP (inverse low-p... This paper introduces current-mode IAFs (inverse active filters) employing DVCCs (differential voltage current conveyors) and grounded passive elements without the parasitic effects. The IAFs enable ILP (inverse low-pass), IBP (inverse band-pass) and IHP (inverse high-pass) responses by adding the circuit current outputs suitably. Additionally the circuit parameters ω0 and Q can be set orthogonally adjusting the circuit passive elements. An achievement example is given together with simulation results by PSPICE. 展开更多
关键词 ANALOG CIRCUITS IAFs DVCCs
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移动终端Wi-Fi模拟测试系统设计与实现 预览
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作者 常淘沙 《数字通信世界》 2019年第6期15-16,共2页
本文将阐述移动终端Wi-Fi采取测试,在测试中出现的漫游性能测试以及移动连接性测试问题采取分析,同时将测试场景中的方法采取完善和改进,重点分析在实验室的状态下,硬件系统以及控制软件所组成的模拟测试系统。另外,按照移动终端产品采... 本文将阐述移动终端Wi-Fi采取测试,在测试中出现的漫游性能测试以及移动连接性测试问题采取分析,同时将测试场景中的方法采取完善和改进,重点分析在实验室的状态下,硬件系统以及控制软件所组成的模拟测试系统。另外,按照移动终端产品采取测试的结果可以证实,此项测试系统具有可行性,在不同信号强弱的情况下以及漫游环境下展示了测试的作用和目的。 展开更多
关键词 移动终端 WI-FI 模拟 测试系统
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诱发面神经麻痹恒河猴模型口轮匝肌闭口反应的人工面神经假体微电极植入方式研究
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作者 余爵波 张天振 +1 位作者 许栋岳 李克勇 《中华口腔医学杂志》 CAS CSCD 北大核心 2019年第10期670-675,共6页
目的通过人工面神经假体(artificial facial nerve prosthesis,AFNP)微电极诱发单侧周围性面神经麻痹(unilateral peripheral facial paralysis prosthesis,UPFP)恒河猴模型口轮匝肌有效的闭口反应,探讨微电极的最佳植入方式。方法选择... 目的通过人工面神经假体(artificial facial nerve prosthesis,AFNP)微电极诱发单侧周围性面神经麻痹(unilateral peripheral facial paralysis prosthesis,UPFP)恒河猴模型口轮匝肌有效的闭口反应,探讨微电极的最佳植入方式。方法选择4只恒河猴(雌雄各2只,5~6岁,体质量2.0~3.0 kg),切断右侧面神经总干,制作UPFP模型;体外输出频率50 Hz,脉宽0.2 ms的电流刺激患侧口轮匝肌,诱发闭口反应。围绕患侧口轮匝肌,根据口轮匝肌上唇(A处)、下唇(B处)、口角至同侧耳屏的连线方向(C处)和口角水平线方向(D处)4个植入位置,选择6组微电极植入方式:A组为A处植入2路微电极,B处植入1路微电极;B组为A、B、C处各植入1路微电极;C组为A处植入1路微电极,B处植入2路微电极;D组为A、B、D处各植入1路微电极;E组为A、C、D处各植入1路微电极;F组为B、C、D处各植入1路微电极。调节计算机工作站输出的刺激电流强度,分别记录6组使口唇有效闭合所需的阈值电流强度和峰值电流强度(每组检测10次);采用方差分析和LSD-t检验比较各组差异。结果A、B、C、D组均可诱发口唇有效的闭合反应,而E、F组在诱发口唇闭合过程中出现上下唇异常闭合的现象,不能产生有效的闭口反应。A、B、C、D组使患侧口唇有效闭合的阈值电流强度分别为(1.35±0.05)、(1.02±0.04)、(1.40±0.04)和(1.10±0.02)mA(F=295.302,P<0.001),其中B组阈值电流强度显著小于其他组(P<0.05)。A、B、C、D组峰值电流强度分别为(3.95±0.02)、(2.95±0.03)、(3.99±0.05)和(3.51±0.01)mA(F=1014.985,P<0.001),其中B组显著小于其他组(P<0.05)。各组中B组可获得肉眼下最好的闭唇形态且所需的刺激电流强度最小。结论当AFNP刺激侧3路微电极分别植入上唇、下唇及口角与同侧耳屏连线方向上时可获得效果最好的闭口反应,可作为AFNP刺激侧微电极优先采用的方案。 展开更多
关键词 面神经麻痹 微电极 神经网络(计算机) 计算机 模拟 口轮匝肌
LED照明调光技术的研究与分析
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作者 王梦霞 周勤勤 +1 位作者 王忆 项华珍 《中国照明电器》 2019年第5期21-25,共5页
伴随着半导体照明技术应用的日臻成熟,对LED调光技术的要求越来越高,对其研究也愈加深入。本文介绍了目前主流的LED调光技术及对LED调光的基本要求,主要就脉宽调制调光、可控硅调光、模拟调光三种LED调光方式的工作原理、优缺点及应用... 伴随着半导体照明技术应用的日臻成熟,对LED调光技术的要求越来越高,对其研究也愈加深入。本文介绍了目前主流的LED调光技术及对LED调光的基本要求,主要就脉宽调制调光、可控硅调光、模拟调光三种LED调光方式的工作原理、优缺点及应用现状作以比较分析,同时探讨了调光方式与通信技术(ZigBee调光、电力载波调光、DMX512调光、DALI调光等)的应用结合,提出了基于绿色、高效的一些调光技术的研发思路。 展开更多
关键词 LED 调光 PWM 可控硅 模拟 通信技术
基于三维重建模拟手术的胸椎椎弓根螺钉通用置钉技术的研究:数字解剖学研究 预览
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作者 王爽 李宏伟 +2 位作者 王海洲 王帅 付玉平 《骨科》 CAS 2019年第2期111-114,共4页
目的应用数字技术对一种胸椎椎弓根螺钉置钉技术的可行性进行探讨。方法以53例中国成人胸椎三维CT为研究对象,在MIMICS软件中进行三维重建,向各节胸椎中置入椎弓根螺钉,进钉点统一选择上关节突外缘与横突上缘交点尾侧3mm,进钉角度在矢... 目的应用数字技术对一种胸椎椎弓根螺钉置钉技术的可行性进行探讨。方法以53例中国成人胸椎三维CT为研究对象,在MIMICS软件中进行三维重建,向各节胸椎中置入椎弓根螺钉,进钉点统一选择上关节突外缘与横突上缘交点尾侧3mm,进钉角度在矢状面垂直于上一椎体下关节突和本椎体下关节突连线,外展角度根据实际情况以棘突为参考确定。完成置钉后,观察各螺钉与周围骨质的关系以确定是否实现最佳位置置钉;以棘突为参考测量外展角,比较左右侧外展角度差异。结果按所设计的方案可完成全部研究对象T1~12椎弓根螺钉的置钉,共1272枚螺钉,除T3、T4双侧螺钉的外展角差异无统计学意义外,其余节段螺钉双侧外展角的差异均有统计学意义(P均<0.05)。结论统一进钉点和矢状面进钉角度的方法可完成胸椎椎弓根螺钉置钉,考虑到多数椎体双侧椎弓根螺钉角度存在差异,应在术前完善三维CT等检查以明确解剖情况,必要时进行数字化模拟手术以提高置钉准确性。 展开更多
关键词 胸椎 椎弓根螺钉 计算机 模拟
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KMT2D deficiency enhances the anti-cancer activity of L48H37 in pancreatic ductal adenocarcinoma 预览
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作者 Si-Si Li Wei-Liang Jiang +8 位作者 Wen-Qin Xiao Kai Li Ye-Fei Zhang Xing-Ya Guo Yi-Qi Dai Qiu-Yan Zhao Ming-Jie Jiang Zhan-Jun Lu Rong Wan 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第8期599-621,共23页
BACKGROUND Novel therapeutic strategies are urgently needed for patients with a delayed diagnosis of pancreatic ductal adenocarcinoma(PDAC)in order to improve their chances of survival.Recent studies have shown potent... BACKGROUND Novel therapeutic strategies are urgently needed for patients with a delayed diagnosis of pancreatic ductal adenocarcinoma(PDAC)in order to improve their chances of survival.Recent studies have shown potent anti-neoplastic effects of curcumin and its analogues.In addition,the role of histone methyltransferases on cancer therapeutics has also been elucidated.However,the relationship between these two factors in the treatment of pancreatic cancer remains unknown.Our working hypothesis was that L48H37,a novel curcumin analog,has better efficacy in pancreatic cancer cell growth inhibition in the absence of histonelysine N-methyltransferase 2D(KMT2D).AIM To determine the anti-cancer effects of L48H37 in PDAC,and the role of KMT2D on its therapeutic efficacy.METHODS The viability and proliferation of primary(PANC-1 and MIA PaCa-2)and metastatic(SW1990 and ASPC-1)PDAC cell lines treated with L48H37 was determined by CCK8 and colony formation assay.Apoptosis,mitochondrial membrane potential(MMP),reactive oxygen species(ROS)levels,and cell cycle profile were determined by staining the cells with Annexin-V/7-AAD,JC-1,DCFH-DA,and PI respectively,as well as flow cytometric acquisition.In vitro migration was assessed by the wound healing assay.The protein and mRNA levels of relevant factors were analyzed using Western blotting,immunofluorescence and real time-quantitative PCR.The in situ expression of KMT2D in both human PDAC and paired adjacent normal tissues was determined by immunohistochemistry.In vivo tumor xenografts were established by injecting nude mice with PDAC cells.Bioinformatics analyses were also conducted using gene expression databases and TCGA.RESULTS L48H37 inhibited the proliferation and induced apoptosis in SW1990 and ASPC-1 cells in a dose-and time-dependent manner,while also reducing MMP,increasing ROS levels,arresting cell cycle at the G2/M stages and activating the endoplasmic reticulum(ER)stress-associated protein kinase RNA-like endoplasmic reticulum kinase/eukaryotic initiation factor 2� 展开更多
关键词 Pancreatic neoplasms CURCUMIN ANALOG HISTONE METHYLTRANSFERASE 2D Therapeutic effects BIOINFORMATICS
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数字建模分析倒退旋转法在腰椎椎体单侧穿刺椎体后凸成形术的适用性 预览
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作者 王雷宁 赵刘军 +5 位作者 于亮 顾勇杰 徐荣明 王力冉 张吉辉 肖武 《中国骨伤》 CAS CSCD 2019年第6期524-530,共7页
目的:利用Mimics软件建立腰椎的3D模型,使用模拟穿刺来观察倒退旋转法在腰椎椎体单侧穿刺椎体后凸成形术的适用性及进针参数。方法:选取24例全腰椎螺旋CT扫描初次胸椎骨质疏松性骨折、腰椎无异常骨质破坏的影像学资料,其中男女各12例,应... 目的:利用Mimics软件建立腰椎的3D模型,使用模拟穿刺来观察倒退旋转法在腰椎椎体单侧穿刺椎体后凸成形术的适用性及进针参数。方法:选取24例全腰椎螺旋CT扫描初次胸椎骨质疏松性骨折、腰椎无异常骨质破坏的影像学资料,其中男女各12例,应用Mimics软件对原始DICOM文件进行3D建模,分离出各节段椎体,直接导入3-matic软件后约束其椎体后壁进行标准化测量后以椎弓根中点作一垂直于中切面及椎体后壁的素描图,在素描图上进行模拟穿刺,记录穿刺针可活动范围的角度参数及距离参数,记录穿刺针在最大外倾角时落在椎体中切线前、中、后区的穿越点,并进行比较分析。结果:所有数据在左右两侧差异均无统计学意义(P>0.05),不同节段数据在两性差异有统计学意义(P<0.05),男女性L1-L5最大外倾角均逐渐增大,男性从(33.41±1.31)°到(56.53±4.71)°,女性从(28.58±2.55)°到(53.86±2.68)°,所有穿越点未落在前区,其中女性26.67%落在中区,男性3.33%落在中区,A、B、C分区在性别上差异有统计学意义(P<0.05)。结论:倒退旋转法理论上均能满足椎体压缩性骨折对穿刺点的要求,其中男性及下腰椎更加适用倒退旋转法。最大外倾角的测定对倒退旋转法有指导性意义。 展开更多
关键词 穿刺术 椎体后凸成形术 计算机 模拟 骨质疏松性骨折
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Monocarbonyl curcumin analog A2 potently inhibits angiogenesis by inducing ROS-dependent endothelial cell death
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作者 Bin Liu Liu-su Cui +3 位作者 Bo Zhou Ling-ling Zhang Zhi-hui Liu Lu Zhang 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第11期1412-1423,共12页
Excessive and abnormal vessel growth plays a critical role in the pathogenesis of many diseases,such as cancer.Angiogenesis is one of the hallmarks of cancer growth,invasion,and metastasis.Discovery of novel antiangio... Excessive and abnormal vessel growth plays a critical role in the pathogenesis of many diseases,such as cancer.Angiogenesis is one of the hallmarks of cancer growth,invasion,and metastasis.Discovery of novel antiangiogenic agents would provide new insights into the mechanisms of angiogenesis,as well as potential drugs for cancer treatment.In the present study,we investigated the antiangiogenic activity of a series of monocarbonyl analogs of curcumin synthesized previously in our lab.We found that curcumin analog A2 displayed the full potential to be developed as a novel antiangiogenic agent.Curcumin analog A2 at and above 20μM dramatically inhibited the migration and tube formation of human umbilical vein endothelial cells(HUVECs)in vitro,new microvessels sprouting from the rat aortic rings ex vivo and newly formed microvessels in chicken chorioallantoic membranes(CAMs)and Matrigel plus in vivo.We further demonstrated that curcumin analog A2 exerted its antiangiogenic activity mainly through inducing endothelial cell death via elevating NADH/NADPH oxidase-derived ROS.Curcumin analog A2 at the antiangiogenic concentrations also triggered autophagy in HUVECs,but this process is neither a pre-requisite for toxicity,leading to the cell death nor a protective response against the toxicity of curcumin analog A2.In conclusion,we demonstrate for thefirst time the potent antiangiogenic activity of the monocarbonyl curcumin analog A2,which could serve as a promising potential therapeutic agent for the prevention and treatment angiogenesis-related diseases,such as cancer. 展开更多
关键词 monocarbonyl curcumin analog ANGIOGENESIS apoptosis autophagy NECROPTOSIS reactive oxygen species vascular endothelial cell bafilomycin A1 WORTMANNIN
Antioxidant response and bioavailability of methionine hydroxy analog relative to DL-methionine in broiler chickens
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作者 Youli Wang Xiaonan Yin +3 位作者 Dafei Yin Zhao Lei Tahir Mahmood Jianmin Yuan 《动物营养:英文版》 2019年第3期241-247,共7页
This study was designed to compare the effect of methionine(Met)sources(DL-methionine[DLM]and DL-2-hydroxy-4-methylthio-butanoic acid(HMTBa))and their supplementation levels on broiler growth performance and redox sta... This study was designed to compare the effect of methionine(Met)sources(DL-methionine[DLM]and DL-2-hydroxy-4-methylthio-butanoic acid(HMTBa))and their supplementation levels on broiler growth performance and redox state.A 2 x 2 factorial arrangement was used with 2 sources(DLM and HMTBa)and 2 supplementation levels(0.05% and 0.252%)of Met.A total of 480 one-day-old broiler chicks were randomly divided into 4 treatments with 8 replicates per treatment(15 birds per replicate).The experiment lasted for 21 d.Broiler growth performance,redox capacity,redox-related genes expression,and Met transporters in different tissues were tested.Broilers fed high Met supplementation levels had improved(P<0.05)body weight(BW).average daily gain(ADG)and feed conversion ratio(FCR).Similarly,broilers fed high Met levels had better(P<0.05)antioxidant abilities in the serum,small intestine,and liver.Whereas,interactive effects(P<0.05)were also observed between Met sources and levels.Compared with DLM.birds fed HMTBa diets had decreased(P<0.05)total glutathione(T-GSH)and oxidized glutathione(GSSG)contents in duodenum,ileum,and liver.Similarly,broilers fed HMTBa supplemented diets had increased(P<0.05)thioredoxin(Trx)gene expression in the duodenum and ileum,but decreased(P<0.05)glutaredoxin(Grx).glutathione reductase(CSR).and glutathione synthetase(GSS)genes expression.Furthermore,lower gene expression of Na+ and Cl-dependent neutral and cationic amino acid transporter(ATB0,+).and Na+ dependent neutral amino acid transporter(B0 AT)in the duodenum brush border,but higher gene expression of diamine acetyltransferase 1(SAT1)and Na+-independent branched-chain and aromatic amino acid transporter(LAT1)in the jejunum and ileum basement membrane along with higher expression of the proton dependent monocarboxylate transporter 1(MCT1)gene in the ileum were detected in birds fed HMTBa diets.In conclusion.DLM can be effectively used in glutathione synthesis to exert antioxidant functions,whereas HMTBa favors S-adenosylmethionine(SAM)synthesis and t 展开更多
关键词 Amino acid TRANSPORTER BROILER DL-METHIONINE METHIONINE HYDROXY ANALOG Oxidation resistance
CNB-001 reduces paraplegia in rabbits following spinal cord ischemia 预览
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作者 Paul A. Lapchak Paul D. Boitano +5 位作者 Rene Bombien Daisy Chou Margot Knight Anja Muehle Mihaela Te Winkel Ali Khoynezhad 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第12期2192-2198,共7页
aortic aneurysm repair and thoracic endovascular aortic repair results in devastating clinical deficits in patients. Because spinal cord ischemia is inadequately treated, we studied the effects of [4-((1E)-2-(5-(4-hyd... aortic aneurysm repair and thoracic endovascular aortic repair results in devastating clinical deficits in patients. Because spinal cord ischemia is inadequately treated, we studied the effects of [4-((1E)-2-(5-(4-hydroxy-3-methoxystyryl-)-1-phenyl-1H-pyrazoyl-3-yl) vinyl)-2-methoxy-phenol)](CNB-001), a novel curcumin-based compound, in a rabbit SCI model. CNB-001 is known to inhibit human 5-lipoxygenase and 15-lipoxygenase and reduce the ischemia-induced inflammatory response. Moreover, CNB- 001 can reduce the level of oxidative stress markers and potentiate brain-derived neurotrophic factor and brain-derived neurotrophic factor receptor signaling. The Tarlov scale and quantal analysis technique results revealed that CNB-001 administered as an intravenous dose (bolus) 30 minutes prior to spinal cord ischemia improved the behaviors of female New Zealand White rabbits. The improvements were similar to those produced by the uncompetitive N-methyl-D-aspartate receptor antagonist memantine. At 48 hours after aortic occlusion, there was a 42.7% increase (P < 0.05) in tolerated ischemia duration (n = 14) for rabbits treated with CNB-001 (n = 16), and a 72.3% increase for rabbits treated with the positive control memantine (P < 0.05)(n = 23) compared to vehicle-treated ischemic rabbits (n = 22). CNB-001 is a potential important novel treatment for spinal cord ischemia induced by aortic occlusion. All experiments were approved by the CSMC Institutional Animal Care and Use Committee (IACUC #4311) on November 1, 2012. 展开更多
关键词 curcumin analog SPINAL CORD injury SPINAL CORD ischemia thoraco-abdominal AORTIC aneurysm thoracic ENDOVASCULAR AORTIC repair motor function neuroprotection NEUROREPAIR
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Effect of herb-partitioned moxibustion for primary dysmenorrhea:a randomized clinical trial
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作者 Liu Yinghua Sun Jing +2 位作者 Shi Ling Yan Ying Wang Xin 《中医杂志:英文版》 SCIE CAS CSCD 2019年第2期237-245,共9页
OBJECTIVE: To observe the effect of herb-partitioned moxibustion(HPM) for primary dysmenorrhea.METHODS: Six hundred and forty patients were randomized assigned(1∶1) to HPM group and control group. Duration of treatme... OBJECTIVE: To observe the effect of herb-partitioned moxibustion(HPM) for primary dysmenorrhea.METHODS: Six hundred and forty patients were randomized assigned(1∶1) to HPM group and control group. Duration of treatment was 3 months with 3 month follow-up. The primary outcome was pain relief measured by visual analogue scale(VAS). The second outcomes were Cox Menstrual Symptom Scale(CMSS), menstrual pain duration and frequency of analgesics usage. The exploratory outcome included quality of life,RESULTS: After the 3-month treatment and follow-ups, the pain intensity measured by VAS was significantly reduced in both groups compared with baseline(P < 0.05), and it was significantly decreased in HPM group than that of control group(P < 0.001). The higher proportion of participants in the HPM group had a decrease of at least 50% in VAS at the end of treatment, as compared with the control group(P < 0.001). At the 3 rd and 6 th month, the menstrual pain duration, CMSS score and frequency of analgesics usage in HPM group were significantly lower than those of control group(P < 0.05). After 3 month treatment and follow-ups,the scores of physical, psychological, social and environmental domains were significantly increased than baseline in both groups(P < 0.05),and the sores of physical, psychological and environmental domains were significantly higher in HPM group than those of control group(P < 0.05).CONCLUSION: Herb-partitioned moxibustion reduced menstrual pain and improved quality of life,these were sustained for up to 3 months after treatment. Further research is needed to understand long term effect and the mechanism of the intervention. 展开更多
关键词 DYSMENORRHEA MOXIBUSTION Visual ANALOG scale Quality of life RANDOMIZED clinical TRIAL
基于MCGS触摸屏模拟量控制的应用 预览
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作者 叶春琴 《无线互联科技》 2019年第7期28-29,共2页
在温度控制、变频器速度控制等模拟量控制中,需要电流或者电压输入PLC模拟量模块,然后按照程序的要求控制输送量。文章论述了在调试过程中可以使用触摸屏模拟控制模拟量,利用脚步程序控制输出,达到相同的效果。
关键词 三菱PLC 模拟量 脚本程序
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Production of a trioxacarcin analog by introducing a C-3 dehydratase into deoxysugar biosynthesis
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作者 Yi Shen Qiu-Yue Nie +3 位作者 Yue Yin Hai-Xue Pan Bin Xu Gong-Li Tang 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第5期539-541,共3页
Microbial natural products have always performed a prominent role in the history of drug discovery and development[1].These secondary metabolites have a remarkable range of biological activities which are mainly cause... Microbial natural products have always performed a prominent role in the history of drug discovery and development[1].These secondary metabolites have a remarkable range of biological activities which are mainly caused by their complicated scaffolds and different functional groups[2].Various modification reactions are involved in the biosynthesis of these bioactive natural products,which can be divided into three different stages:namely pre-assembly modification,assembly line modification,and post-assembly modification.Undoubtedly,post-modification is often the most important modification that contributes to the structural diversity and good biological activities of most natural products,including redox,methylation,glycosylation,acetylation,prenylation,halogenation,etc.[3]. 展开更多
关键词 PRODUCTION a trioxacarcin ANALOG deoxysugar BIOSYNTHESIS
Subthreshold analog techniques 预览
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作者 Nanjian Wu 《半导体学报:英文版》 EI CAS CSCD 2019年第2期5-6,共2页
IEEE J.Solid-State Circuits,2019,doi:10.1109/JSSC.2018.2889847Low power is a fundamental requirement in state-ofthe-art IC designs,where lower and scalable supply voltagesare demanded due to the power benefits of digi... IEEE J.Solid-State Circuits,2019,doi:10.1109/JSSC.2018.2889847Low power is a fundamental requirement in state-ofthe-art IC designs,where lower and scalable supply voltagesare demanded due to the power benefits of digital circuits under near-and sub-threshold supply voltages. 展开更多
关键词 DSM SUBTHRESHOLD ANALOG TECHNIQUES OTA
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