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一种高速且输出摆幅可调的SubLVDS发送端电路
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作者 王巍 穆春霖 +2 位作者 金蔚然 王书星 杨龙 《微电子学与计算机》 2025年第6期146-154,共9页
超低压差分信号是实现芯片内外数据高速串行传输的有效方式。传统电路无法在同一电压下调整差分输出摆幅来满足不同的应用情况。为了解决传统技术差分输出信号摆幅无法改变的问题,设计了一种输出摆幅可调的低压差分信号发送端电路。该... 超低压差分信号是实现芯片内外数据高速串行传输的有效方式。传统电路无法在同一电压下调整差分输出摆幅来满足不同的应用情况。为了解决传统技术差分输出信号摆幅无法改变的问题,设计了一种输出摆幅可调的低压差分信号发送端电路。该电路采用双电流源结构,通过改变流过驱动器电路电流的大小,进而调整输出差分摆幅,可以在同一电源电压和共模电压下输出两种不同幅值的差分摆幅信号。仿真结果表明:在输入信号数据速率为2 Gbps时,该电路可以在两种摆幅模式下平稳切换,分别输出约±152 mV和±351 mV的差分信号摆幅,功耗约为9.1 mW,共模电压均约为0.955 V。 展开更多
关键词 超低压差分信号 串行传输 共模电压 差分摆幅
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Correction:Transition Metal Carbonitride MXenes Anchored with Pt Sub‑nanometer Clusters to Achieve High‑Performance Hydrogen Evolution Reaction at All pH Range
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作者 Zhihao Lei Sajjad Ali +18 位作者 CI Sathish MuhammadIbrar Ahmed Jiangtao Qu RongkunZheng Shibo Xi Xiaojiang Yu M.B.H.Breese Chao Liu Jizhen Zhang Shuai Qi Xinwei Guan Vibin Perumalsamy Mohammed Fawaz Jae‑Hun Yang Mohamed Bououdina Kazunari Domen Ajayan Vinu Liang Qiao Jiabao Yi 《Nano-Micro Letters》 2025年第7期452-452,共1页
Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corre... Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corrected from 1 to 2.The correct author affiliation has been provided in this Correction and the original article[1]has been corrected. 展开更多
关键词 CARBONITRIDES hydrogen evolution reaction Pt sub nanometer clusters transition metals
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Evaluation of 68 mg Etonogestrel Subdermal Implant Uptake in a Tertiary Hospital in Nigeria: A 5-Year Retrospective Review
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作者 Emmanuel I. Ogumu Chidebe C. Anikwe +4 位作者 Osita S. Umeononihu Mbanefo Paul Okeke Onyechrelam M. Ogelle Ifenyiwa H. Anikwe Lucky O. Lawani 《Open Journal of Obstetrics and Gynecology》 2025年第2期278-288,共11页
Introduction: Family planning is one of the pillars of the Safe Motherhood Initiative which is aimed at reducing unwanted pregnancy and maternal death. Objective: To evaluate the uptake, efficacy, and safety profile o... Introduction: Family planning is one of the pillars of the Safe Motherhood Initiative which is aimed at reducing unwanted pregnancy and maternal death. Objective: To evaluate the uptake, efficacy, and safety profile of 68 mg etonogestrel subdermal implant in Alex Ekwueme Federal University Teaching Hospital Abakaliki (AEFUTHA), Ebonyi State. Materials and Methods: A 5-year retrospective descriptive analysis was carried out on 68 mg etonogestrel subdermal implant uptake among family planning attendees in AEFUTHA. The medical records of the clients that had 68 mg etonogestrel subdermal implant insertion were studied. Socio-demographic characteristics, side effects, discontinuation, and reasons for discontinuation were extracted and analyzed. Analysis was done with SPSS version 20. Data obtained were represented using frequency tables and pie chart. Results: During the study period, 2538 women accepted various methods of contraception, 14.3% (364) of the women used Implanon. The mean age of 68 mg etonogestrel subdermal implant users was 30.7 ± 13.4 years with a range of 20 - 44. Multiparous clients constituted 54.5%. The majority (55.2%) had secondary education as their highest level of education. Less than 20% of the acceptors had side effects, the commonest 24 (42.9%) being prolonged menstrual flow and followed by irregular menstrual flow 18 (32.1%). Discontinuation rate was 17.9%;desire to conceive. 40 (61.5%) was the commonest reason for discontinuation. Only one (0.3%) acceptor reported serious itching at the site of insertion. None of the women reported pregnancy during the period of use (Pearl Index = 0). Conclusion: The acceptance rate of 68 mg etonogestrel subdermal implant among the women is low, however, it is found be effective with good continuation rate in the center. Efforts should be made to increase its uptake so as to prevent unwanted pregnancy and associated sequelae. 展开更多
关键词 IMPLANON sub-Dermal Implant CONTRACEPTION Abakaliki NIGERIA
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The Risk Factors of Infertility Associated with Unsafe Abortion in a Sub-Saharan Population
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作者 Justin Esimo Mboloko Charles Bampanzi Moangi +7 位作者 Pathou Ipanga Mampuya Junior Mata Mboloko Patrick Sendeke Mogwo Annie Azima Egbolo Serge Litambelo Etana Dan Kabengele Ngoyi Athena Mwakila Asana Guy Sibo Monzango 《Open Journal of Obstetrics and Gynecology》 2025年第1期67-77,共11页
Background: Unsafe abortion (USA) is defined as the termination of a non-desired pregnancy, performed by an unqualified person or in an environment without minimum medical standards, or both. It can impact negatively ... Background: Unsafe abortion (USA) is defined as the termination of a non-desired pregnancy, performed by an unqualified person or in an environment without minimum medical standards, or both. It can impact negatively the fertility in the future by tubo-peritoneal lesions. The current study aimed to highlight the infertility factors associated with USA. Material and Methods: From January 1st 2000 to December 31st 2021, a total of 3876 patients that sought care for infertility in the University Clinic of Kinshasa and the Edith Medical Center were enrolled. The socio-demographic, clinical and paraclinical variables were recorded and analyzed in relation to USA history. Results: The patients’ average age was 33.4 ± 5.7 years. Half of them were housewives;about sixty percent of the patients were nulliparous (59.31%). Seventy percent had a secondary infertility with 43.33% having a history of unsafe abortion. The main diagnosis was genital infections and uterus myoma. The chronic endometritis, bilateral tubal occlusion and Uterine synechiae were more associated with USA group. The spermogram anomalies and other partners’ lesions seemed of infectious origin. Conclusion: The USA remains a more frequent phenomenon in our setting. The chronic endometritis, bilateral tubal occlusion, uterine synechiae and indirectly uterus myoma were the infertility factors related to USA. The genital infection of any origin seems to be the main denominator underlying the female and the male infertility in our setting. 展开更多
关键词 Unsafe Abortion Secondary Infertility Infertility Factors Tubal Infertility sub-Saharan Setting
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sub-500 fs宽度2μm光纤激光振荡器研究进展(特邀)
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作者 马晓冉 张恒 +2 位作者 冯天利 李涛 杨克建 《光电技术应用》 2024年第1期1-10,共10页
2μm波段超快激光持续时间短,峰值功率高,光谱范围宽,同时处在大气窗口,多种有机、无机气体分子的吸收峰和人眼安全波段,已广泛应用于生物医疗、激光雷达和非金属材料加工等领域。利用光纤锁模激光振荡器产生2μm波段超快激光是一种最... 2μm波段超快激光持续时间短,峰值功率高,光谱范围宽,同时处在大气窗口,多种有机、无机气体分子的吸收峰和人眼安全波段,已广泛应用于生物医疗、激光雷达和非金属材料加工等领域。利用光纤锁模激光振荡器产生2μm波段超快激光是一种最直接简单的技术方法,具有结构紧凑、光束质量高和成本低等优点。然而,目前关于sub-500 fs的2μm波段的光纤激光振荡器却鲜有报道。基于传统孤子和色散管理孤子两种孤子锁模方式,全面介绍了目前2μm波段sub-500 fs光纤振荡器的研究进展,并总结了实现sub-500 fs脉宽2μm超快激光的关键技术。针对不同的应用领域的具体需求,对2μm超快激光光纤振荡器的未来发展进行展望。 展开更多
关键词 光纤激光器 2μm sub-500 fs 超短脉冲 振荡器
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基于生物信息学分析的弓形虫TgSUB3多抗制备
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作者 李瑾 张欣 +6 位作者 雷战 谢金晶 王龙江 尹昆 徐超 魏庆宽 孙慧 《中国病原生物学杂志》 CSCD 北大核心 2024年第6期690-694,共5页
目的在利用生物信息学全面分析TgSUB3序列的基础上,制备针对该蛋白B细胞抗原表位的兔源多克隆抗体。方法采用生物信息学软件对TgSUB3蛋白的理化性质、空间结构、磷酸化/糖基化位点、B细胞抗原表位等进行分析。用原核表达、纯化的TgSUB3... 目的在利用生物信息学全面分析TgSUB3序列的基础上,制备针对该蛋白B细胞抗原表位的兔源多克隆抗体。方法采用生物信息学软件对TgSUB3蛋白的理化性质、空间结构、磷酸化/糖基化位点、B细胞抗原表位等进行分析。用原核表达、纯化的TgSUB3重组蛋白免疫新西兰大白兔,于4次加强免疫后第7 d制备兔血清,采用Protein A亲和纯化抗体蛋白,分别利用SDS-PAGE和ELISA分析抗体纯度和效价。结果生物信息学分析TgSUB3为不稳定亲水性蛋白,无信号肽,跨膜区为19-39aa,包含1个Peptidases_S8结构域(358-617aa)。二级结构中无规卷曲占51.29%,α螺旋占26.11%。TgSUB3包含65个磷酸化位点和126个糖基化位点。B细胞抗原表位区集中在45-290aa和715-937aa。SDS-PAGE显示纯化的TgSUB3多抗为单一55 ku条带,ELISA检测TgSUB3抗体滴度为1:102400。结论成功制备了兔源TgSUB3抗血清,经纯化获得高纯度高滴度的多抗。 展开更多
关键词 弓形虫 sub3蛋白 多克隆抗体 生物信息学
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基于FullSubNet的单通道实时语音增强算法 被引量:1
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作者 许苏魁 万家山 +1 位作者 潘敬敏 胡婷婷 《科学技术创新》 2024年第9期95-98,共4页
针对语音实时通信场景,本文提出一种基于循环神经网络的单通道实时语音增强方案。通过模型层面融合全频带和子频带特征以同时捕获全频带信息和局部语谱特征,并且基于循环神经网络的内在时序性,实现了按帧推理实时输出的要求。实验结果显... 针对语音实时通信场景,本文提出一种基于循环神经网络的单通道实时语音增强方案。通过模型层面融合全频带和子频带特征以同时捕获全频带信息和局部语谱特征,并且基于循环神经网络的内在时序性,实现了按帧推理实时输出的要求。实验结果显示,在DNS-Challenge InterSpeech 2020的测试集上,本文按帧输出方式的模型可以取得2.85的pesq值。在系统固定延时32 ms的情况下,使用NVidia GeForce RTX 3060 GPU处理16 ms一帧长度的数据耗时1.5 ms;如果将模型转为onnx格式,在Intel i7@2.7GHz CPU上处理一帧数据耗时3.8 ms。 展开更多
关键词 全频带和子频带融合 实时语音增强 噪声去除 循环神经网络 深度学习
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2024年2月华东和华中大范围低温雨雪冰冻灾害的成因和可预报性分析 被引量:6
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作者 赵俊虎 赵语欣 +3 位作者 贾小龙 张涵 熊开国 曾宇星 《气象》 北大核心 2025年第1期17-29,共13页
利用全国2374个站点的逐日气温和降水资料、NCEP/NCAR大气环流再分析资料和Hadley中心的海温资料,研究了2024年2月华东和华中大范围低温雨雪冰冻灾害成因和可预报性。结果表明:2024年2月上旬和下旬这两次大范围低温雨雪冰冻天气过程,发... 利用全国2374个站点的逐日气温和降水资料、NCEP/NCAR大气环流再分析资料和Hadley中心的海温资料,研究了2024年2月华东和华中大范围低温雨雪冰冻灾害成因和可预报性。结果表明:2024年2月上旬和下旬这两次大范围低温雨雪冰冻天气过程,发生地区重叠度高,冰雪灾害严重;影响两次过程的副热带和中高纬环流系统配置较为一致,西北太平洋副热带高压(以下简称副高)稳定偏强和偏西,西伯利亚高压、南支槽和西北太平洋反气旋阶段性同步偏强,形成较强的协同作用,西伯利亚高压增强导致冷空气南下,副高、南支槽和西北太平洋反气旋同步增强则为华东和华中提供了充沛的水汽条件;2023年5月至2024年4月赤道中东太平洋地区发生了一次中等强度的El Nino事件,冬季热带印度洋和热带北大西洋海温异常偏暖,三大洋海温异常共同导致了副高持续偏强,也有利于西北太平洋反气旋的阶段性发展和增强,为2月的两次过程提供了充沛的水汽条件;次季节模式对两次过程的预报时效在1~2周左右,起报时间在2周以上时,目前模式无法准确预测欧亚中高纬环流系统的异常特征,导致对两次过程的预测能力较低。 展开更多
关键词 低温雨雪冻雨 El Nino 成因 次季节可预报性
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The Modified BAPGs Method for Support Vector Machine Classifier with Truncated Loss
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作者 Kexin Ren 《Applied Mathematics》 2024年第4期267-278,共12页
In this paper, we modify the Bregman APG<sub>s</sub> (BAPG<sub>s</sub>) method proposed in (Wang, L, et al.) for solving the support vector machine problem with truncated loss (HTPSVM) given in... In this paper, we modify the Bregman APG<sub>s</sub> (BAPG<sub>s</sub>) method proposed in (Wang, L, et al.) for solving the support vector machine problem with truncated loss (HTPSVM) given in (Zhu, W, et al.), we also add an adaptive parameter selection technique based on (Ren, K, et al.). In each iteration, we use the linear approximation method to get the explicit solution of the subproblem and set a function to apply the Bregman distance. Finally, numerical experiments are performed to verify the efficiency of BAPG<sub>s</sub>. 展开更多
关键词 HTPSVM Bregman Distance BAPG<sub>ssub> Algorithm
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A Comparative Study between Landmark Based and Real Time Ultrasound Guided Sub Arachnoid Block
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作者 Kunal Tewari Om Bahadur Thapa +4 位作者 Deepak Mishra Manjot Multani Jyotsna Sharma Akash Ray Mohapatra Sandhya Khwaunju 《Open Journal of Anesthesiology》 2024年第4期118-125,共8页
Background: Sub arachnoid block (SAB) performed by traditional landmark palpation technique can be inaccurate. This problem is exacerbated by altered patient anatomy due to obesity and age-related changes. A pre-proce... Background: Sub arachnoid block (SAB) performed by traditional landmark palpation technique can be inaccurate. This problem is exacerbated by altered patient anatomy due to obesity and age-related changes. A pre-procedural ultrasound scan of the lumbar spine has been shown to be of benefit in guiding lumbar epidural insertion in obstetric patients. Information on the use of real-time ultrasound (RUS) guided SAB, to date, been limited. This study compared RUS guided SAB to traditional landmark guided technique in patients undergoing spinal anesthesia for different surgical procedures. Methods: This was a prospective, single center, comparative observational study conducted in the department of anesthesiology at our center. 560 patients who underwent spinal anesthesia either by landmark based technique or real-time ultrasound-guided methods. The primary outcome was the first attempt success rate of dural puncture when employing the two methods. Results: Baseline characteristics were similar in the two study groups. The first attempt success rate of dural puncture in landmark guided group was 64.3% compared to 72.6% in the ultrasound guided group. This difference was not statistically significant. The procedure performance time was significantly shorter with landmark palpation compared to use of real-time ultrasound guided method. Conclusion: Use of RUS-guided technique does not significantly improve the first attempt success rate of SAB dural puncture during spinal anesthesia compared to the traditional landmark-guided technique. 展开更多
关键词 sub Arachnoid Block (SAB) Real Time Ultrasound (RUS)
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陆相淡水湖盆细粒沉积成因机制及页岩油储集特征——以鄂尔多斯盆地西南部三叠系延长组长7_3亚段为例 被引量:3
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作者 刘显阳 刘江艳 +6 位作者 王秀娟 郭芪恒 吕奇奇 杨智 张岩 张忠义 张文选 《石油勘探与开发》 北大核心 2025年第1期84-98,共15页
基于鄂尔多斯盆地西南部三叠系延长组长73亚段页岩油勘探实践进展,综合野外露头、钻井、测井、岩心、地球化学等资料,以及水槽实验模拟等技术手段,开展陆相湖盆细粒沉积古环境、岩相组合和分布、沉积成因及页岩油储集特征的系统研究。... 基于鄂尔多斯盆地西南部三叠系延长组长73亚段页岩油勘探实践进展,综合野外露头、钻井、测井、岩心、地球化学等资料,以及水槽实验模拟等技术手段,开展陆相湖盆细粒沉积古环境、岩相组合和分布、沉积成因及页岩油储集特征的系统研究。结果表明:①长73亚段沉积期研究区古环境整体表现为温暖湿润、梅雨事件频发、水体深度较大的淡水湖盆特征,古地貌呈现西南陡、东北缓的不对称型,可进一步细分为湖底深洼、古沟道、湖底古脊等微古地貌单元。②长73亚段发育一套极细砂岩、粉砂岩、泥页岩、凝灰岩等细粒沉积,垂向多呈薄互层—纹层组合分布,砂岩粒径大多小于62.5μm,单层厚度为0.05~0.64 m,含完整植物碎片,发育波状层理、逆粒序-正粒序组合、爬升沙纹层理等沉积构造,揭示异重流沉积成因。③环形水槽模拟实验再现了异重流搬运过程及沉积特征,主要表现为初期的密度流速差造成头部较厚且粒径较大,上部较薄且粒径偏小的特征;中期滑水作用促使流体头部抬升并向前快速搬运,由此产生的多个“新前端”促使粉砂岩、泥质粉砂岩等细粒砂岩向湖盆中部长距离搬运。④明确了盆地西南部细粒砂质岩以异重流成因为主,指出频繁发育的洪水事件、西南部陡坡地形是异重流发育的主控因素。⑤长73亚段砂岩、泥页岩发育微纳米孔喉系统,不同岩性均含油,但可动油含量差异大,砂岩中可动油含量最大。⑥明确了长73亚段多期异重流砂岩与泥页岩形成的细粒沉积复合体具有“整体含油、差异储集”特征,低TOC泥岩与粉砂岩组合为目前最有利的勘探目标。 展开更多
关键词 细粒沉积 异重流 水槽模拟实验 储集特征 长7_(3)亚段 三叠系延长组 页岩油 鄂尔多斯盆地
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Influence of Angiotensin II on α1-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells
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作者 Itzell Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido +3 位作者 Santiago C. Sigrist-Flores Juan Javier López-Guerrero Enrique Hong Rafael Villalobos-Molina 《Journal of Biosciences and Medicines》 2024年第4期123-134,共12页
Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including func... Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α<sub>1</sub>-adrenergic receptors (α<sub>1</sub>-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10<sup>−5</sup> M), and in some experiments, 5-Methylurapidil (α<sub>1A</sub>-AR antagonist), AH11110A (α<sub>1B</sub>-AR antagonist), or BMY-7378 (α<sub>1D</sub>-AR antagonist), were used to identify the α<sub>1</sub>-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α<sub>1D</sub>-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α<sub>1</sub>-ARs proteins were evaluated. α<sub>1D</sub>-AR increased at 30 and 60 min post Ang II exposure, the α<sub>1A</sub>-AR diminished from 1 to 4 h, while α<sub>1B</sub>-AR remained unchanged over 24 h of Ang II exposure. Ang II induced an increase of α<sub>1D</sub>-AR at short times, and BMY-7378 protected α<sub>1D</sub>-AR from desensitization. 展开更多
关键词 Angiotensin II α<sub>1Dsub>-AR α<sub>1sub>-AR Expression Rat aorta Smooth Muscle Cells
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Water as a Standard Substance of a Logarithmic Poison Scale
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作者 Karsten Strey 《Journal of Biosciences and Medicines》 2024年第1期86-92,共7页
The lethal dose LD<sub>50</sub> represents the most important experimental value for acute toxicity. The simple logarithmic calculation of -log<sub>10</sub> LD<sub>50</sub> = value ... The lethal dose LD<sub>50</sub> represents the most important experimental value for acute toxicity. The simple logarithmic calculation of -log<sub>10</sub> LD<sub>50</sub> = value leads to the possible poison power pLD. As with the pH or pK value, respectively, for acid or the scale of earthquake intensities the logarithm helps making large differences of orders of magnitude easier to understand since they are more comparable. The higher the pLD value, the higher is the power of poison. An increase of the pLD value by 1 stands for a tenfold increase in toxicity. The lethal acute dose for water, one of the most important and at the same time non-toxic substances of all, is about one tenth of the body weight. This leads to a possible pLD value for water of 1, an ideal starting value for a logarithmic poison scale. 展开更多
关键词 LD<sub>50sub> Lethal Dose TOXICITY WATER GLYPHOSATE Poison Scale
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Calibration of CO and CO2 Monitors Used in Periodic Inspection of Vehicles at Fixed Stations for Environmental Control
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作者 Adel Bassuoni Shehata Abdulrahman Rashed Al Askar +2 位作者 Najjy Hamad Al Yami Abdullah Suleiman Al Owaysi Sultan K. Alharbi 《Green and Sustainable Chemistry》 2024年第2期29-41,共13页
Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuri... Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuring the quantitative assessment of emissions for informed decisions on environmental treatments. This paper describes a method for the calibration of CO/CO<sub>2</sub> monitors used for periodic inspections of vehicles in cites. The calibration was performed in the selected ranges: 900 - 12,000 µmol/mol for CO and 2000 - 20,000 µmol/mol for CO<sub>2</sub>. The traceability of the measurement results to the SI units was ensured by using certified reference materials from CO/N<sub>2</sub> and CO<sub>2</sub>/N<sub>2</sub> primary gas mixtures. The method performance was evaluated by assessing its linearity, accuracy, precision, bias, and uncertainty of the calibration results. The calibration data exhibited a strong linear trend with R² values close to 1, indicating an excellent fit between the measured values and the calibration lines. Precision, expressed as relative standard deviation (%RSD), ranged from 0.48 to 4.56% for CO and from 0.97 to 3.53% for CO<sub>2</sub>, staying well below the 5% threshold for reporting results at a 95% confidence level. Accuracy measured as percent recovery, was consistently high (≥ 99.1%) for CO and ranged from 84.90% to 101.54% across the calibration range for CO<sub>2</sub>. In addition, the method exhibited minimal bias for both CO and CO<sub>2</sub> calibrations and thus provided a reliable and accurate approach for calibrating CO/CO<sub>2</sub> monitors used in vehicle inspections. Thus, it ensures the effectiveness of exhaust emission control for better environment. 展开更多
关键词 MONITORS Periodic Inspection CO/CO<sub>2sub> Calibration LINEARITY Precision Accuracy
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南海东部次海盆下地壳倾斜反射体结构特征及成因 被引量:1
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作者 徐子英 姚永坚 +4 位作者 汪俊 唐江浪 高红方 李学杰 曾程辉 《地质学报》 北大核心 2025年第1期265-276,共12页
南海东部次海盆洋壳内发育了大量强振幅的壳内倾斜反射体,它记录了海盆洋壳增生过程,深入研究海盆下地壳倾斜反射体的结构及成因,对认识南海海盆扩张过程具有重要意义。本文基于深反射多道地震剖面,刻画了东部次海盆下地壳倾斜反射体的... 南海东部次海盆洋壳内发育了大量强振幅的壳内倾斜反射体,它记录了海盆洋壳增生过程,深入研究海盆下地壳倾斜反射体的结构及成因,对认识南海海盆扩张过程具有重要意义。本文基于深反射多道地震剖面,刻画了东部次海盆下地壳倾斜反射体的结构特征及内部变形,初步探讨了其发育成因。研究表明,东部次海盆南、北部都发育强振幅的下地壳倾斜反射体,倾斜反射体大部分终止于Moho反射界面,但南北部倾斜反射体的分布范围、结构特征及成因存在明显差异。东部次海盆下地壳倾斜反射体倾斜长度北长南短,北长约15~22 km,南长约5~8 km;分布范围北大南小,北部南北向长约150 km,南部南北向长约70 km。下地壳倾斜反射区的Moho面埋深起伏差异明显北小南大,北为0.5 s,南有1.2 s。基底北部平坦南部起伏大,洋壳厚度北部厚南部薄,推测东部次海盆洋壳增生过程是非对称性和非均一的。东部次海盆下地壳倾斜反射体的成因可能与同岩浆断裂、水热循环、壳幔过渡区岩浆间隙侵入和基底深大断裂密切相关。 展开更多
关键词 南海 东部次海盆 下地壳倾斜反射体 结构特征 发育成因 洋壳增生过程
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Algorithm for Visualization of Zero Divisor Graphs of the Ring ℤn Using MAPLE Coding
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作者 Nasir Ali 《Open Journal of Discrete Mathematics》 2024年第1期1-8,共8页
This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study ... This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study of ring theory, depict relationships between elements of a ring that multiply to zero. The paper explores the development and implementation of algorithms in MAPLE for constructing these ZDGs. The comparative study aims to discern the strengths, limitations, and computational efficiency of different MAPLE algorithms for creating zero divisor graphs offering insights for mathematicians, researchers, and computational enthusiasts involved in ring theory and mathematical computations. 展开更多
关键词 Zero Divisor Graph Ring Theory Maple Algorithm ℤ<sub>nsub> Modulo n Graph Theory Mathematical Computing
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The Protective Effects of Flavonoids from Scutellaria Baicalensis Georgi Stems and Leaves on Oligodendrocyte Damage Induced by Aβ1-42
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作者 Tangtang Song Yinhui Yao Yazhen Shang 《Pharmacology & Pharmacy》 2024年第1期1-13,共13页
Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. ... Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ<sub>1-42</sub>, an injury model was established by subjecting OLN-93 cells to Aβ<sub>1-42</sub> exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ<sub>1-42</sub>. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ<sub>1-42</sub>-induced damage of OL. 展开更多
关键词 Flavonoids form the Stem and Leaves of Scutellaria baicalensis Georgi Aβ<sub>1-42sub> OLIGODENDROCYTES DAMAGE
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陆相富有机质页岩纹层组合特征与页岩油差异富集机理--以鄂尔多斯盆地三叠系延长组长7_(3)亚段为例 被引量:1
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作者 牛小兵 吕成福 +5 位作者 冯胜斌 周钱山 辛红刚 肖月也 李成 淡卫东 《石油勘探与开发》 北大核心 2025年第2期279-291,共13页
通过对鄂尔多斯盆地三叠系延长组7段3亚段(简称长7_(3)亚段)富有机质页岩的纹层(组合)类型、储集特征和页岩油赋存状态等开展系统研究,揭示不同纹层组合约束下页岩油赋存的主控因素;并结合页岩油微运移表征及评价方法,从接力式供烃、阶... 通过对鄂尔多斯盆地三叠系延长组7段3亚段(简称长7_(3)亚段)富有机质页岩的纹层(组合)类型、储集特征和页岩油赋存状态等开展系统研究,揭示不同纹层组合约束下页岩油赋存的主控因素;并结合页岩油微运移表征及评价方法,从接力式供烃、阶梯式运移、多级分异的角度深入探讨页岩油差异富集机理和富集模式。研究表明:①长7_(3)亚段页岩主要发育无纹层型(泥岩)、砂质纹层、凝灰质纹层、混合纹层和富有机质纹层等5类主要纹层组合。②不同纹层组合页岩储集空间存在明显差异,砂质纹层和凝灰质纹层页岩中大量发育的粒间孔、溶蚀孔及生烃增压缝等多尺度孔缝系统构成液态烃赋存的主要场所。③各类纹层组合页岩中页岩油的赋存和分布受有机质丰度、储集性、热演化程度、矿物组成及纹层规模共同控制,砂质、凝灰质纹层等刚性纹层组合页岩的微纳米孔缝中以游离态的轻质组分为主,而有机质、黏土矿物及骨架矿物颗粒表面则以吸附态的重质组分为主。④长7_(3)亚段不同纹层组合页岩间发生了明显的页岩油微运移,整体呈现出富有机质纹层页岩→凝灰质纹层页岩→混合纹层页岩→砂质纹层页岩→泥岩的阶梯式运移特点。⑤多种类型纹层页岩空间叠置关系控制下有机质的“接力式”供烃、多尺度孔缝网络的“阶梯式运移”及不同纹层组合页岩中“有机-无机相互作用”控制下的“多级分异”是导致页岩油在不同纹层组合页岩间油组分差异性的根本原因。 展开更多
关键词 富有机质页岩 纹层组合特征 差异富集机理 页岩油 长73亚段 三叠系延长组 鄂尔多斯盆地
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Besov Estimates for Sub-Elliptic Equations in the Heisenberg Group
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作者 Huimin Cheng Feng Zhou 《Advances in Pure Mathematics》 2024年第9期744-758,共15页
In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Be... In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Besov spaces with more general assumptions on coefficients for both homogeneous equations and non-homogeneous equations. This study of regularity estimates expands the Calderón-Zygmund theory in the Heisenberg group. 展开更多
关键词 Heisenberg Group sub-Elliptic Equations REGULARITY Besov Spaces
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Hepatitis B Vaccination Coverage among University Students in Sub-Saharan Africa: Systematic Review and Meta Analysis
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作者 Lebem Togtoga Abdourahmane Ndong +2 位作者 Saidou Bah Papa Djibril Ndoye Khadim Niang 《Journal of Biosciences and Medicines》 2024年第10期45-58,共14页
Introduction: Hepatitis B is an infectious disease that remains a real public health problem in Africa. Students represent a group at risk for this disease. The objective of this study was to estimate the hepatitis B ... Introduction: Hepatitis B is an infectious disease that remains a real public health problem in Africa. Students represent a group at risk for this disease. The objective of this study was to estimate the hepatitis B vaccination coverage rate among students in sub-Saharan Africa. Methods: A systematic search of databases (PubMed, AJOL) and a manual search of Google Scholar was conducted to retrieve all published studies reporting hepatitis B vaccination coverage among students in sub-Saharan Africa. The pooled coverage rate was estimated with a 95% confidence interval (CI) in a random-effects meta-analysis. Results: A total of 35 studies were included and included 20,520 students. The mean age was 22.1 ± 5.1 years with a predominance of female sex (sex ratio F/M = 1.05). The vaccination coverage rate was 28.8% [95% CI: 22.9% - 34.7%]. Disaggregation allowed to estimate coverage rates of 29.8% [95% CI: 22.9% - 36.7%], 23.4% [95% CI: 9.4% - 37.4%] and 17.0% [95% CI: 14.4% - 19.5%] respectively in West Africa, East Africa and Central Africa. Conclusion: Less than a third of students in sub-Saharan Africa are protected against hepatitis B. However, the majority of this target group is at risk of infection. It would be relevant to screen and, if necessary, vaccinate all new students. 展开更多
关键词 Hepatitis B Vaccination Coverage STUDENTS sub-Saharan Africa
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