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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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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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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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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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A Comparison of Hydrothermal Aging, SO2 and Propene Poisoning Effects on NH3-SCR over Cu-ZSM-5 and Cu-SAPO-34 Catalysts
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作者 Kouadio Brou Albert Koffi Konan Martin +1 位作者 Zran Van Eric-Simon Horo Kone 《Journal of Materials Science and Chemical Engineering》 2024年第5期10-28,共19页
This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both... This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both Cu-SAPO-34 and Cu-ZSM-5. The catalytic activities of fresh, aged and poisoned samples were tested in ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) of NO<sub>x</sub> conditions. The XRD, TG and N<sub>2</sub>-desorption results showed that the structures of the Cu-SAPO-34 and Cu-ZSM-5 remained intact after 750˚C hydrothermally aged, SO<sub>2</sub> and propene poisoned. After hydrothermal aging at 750˚C for 12 h, the NO reduction performance of Cu-ZSM-5 was significantly reduced at lower temperatures, while that of Cu-SAPO-34 was less affected. Moreover, Cu-SAPO-34 catalyst showed high NO conversion with SO<sub>2</sub> or propene compared to Cu-ZSM-5. However, Cu-ZSM-5 showed a larger drop in catalytic activity with SO<sub>2</sub> or propene compared to Cu-SAPO-34 catalyst. The H<sub>2</sub>-TPR results showed that Cu<sup>2 </sup> ions could be reduced to Cu<sup> </sup> and Cu<sup>0</sup> for Cu-ZSM-5, while no significant transformation of copper species was observed for Cu-SAPO-34. Meanwhile, the UV-vis DRS results showed that CuO species were formed in Cu-ZSM-5, while little changes were observed for the Cu-SAPO-34. Cu-SAPO-34 showed high sulfur and hydrocarbon poison resistance compared to Cu-ZSM-5. In summary, Cu-SAPO-34 with small-pore zeolite showed higher hydrothermal stability and better hydrocarbon and sulfur poison resistant than Cu-ZSM-5 with medium-pore. 展开更多
关键词 Hydrothermal Aging Propene and SO<sub>2sub>Poisoning Ammonia-Selective Catalytic Reduction(NH<sub>3sub>-SCR) Cu-SAPO-34 CU-ZSM-5
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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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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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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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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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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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Systematic Analysis of Factors Associated with Late Breast Cancer Screening in Women in Sub-Saharan Africa from 2014 to 2020
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作者 Akossito Hermine Tognon Ahmed Kabore +5 位作者 Nayi Zongo Nestor Bationo Francis Tognon Tchegnonsi Ludmila Akoyi Abdoul Halim Bague Maxime Koine Drabo 《Open Journal of Epidemiology》 2024年第3期480-492,共15页
Research background: Breast cancer remains a major public health problem, with a high number of new cases and deaths each year. However, despite advances in research to improve this disease, there is a high rate of la... Research background: Breast cancer remains a major public health problem, with a high number of new cases and deaths each year. However, despite advances in research to improve this disease, there is a high rate of late detection, leading to diagnosis at an advanced stage and a reduced chance of survival. Objective: The aim of this study is to identify the factors associated with late detection of breast cancer in women in Sub-Saharan Africa from 2014 to 2020.Setting: This systematic review focuses on sub-Saharan Africa. Methods: We searched for articles in four databases (PubMed, Embase, Global-Health and CINAHL) between 2014 and 2020 and performed a narrative synthesis to organize and group the different factors associated with late breast cancer detection. Result: After reviewing 583 publications, 6 studies were selected, highlighting factors such as lack of awareness, knowledge gaps, difficulties in accessing health services and financial constraints associated with late breast cancer screening. The participants, who ranged in number from 20 to 1776, were mainly aged between 18 and 25, with a mean age of 25 years and 6 months. Conclusion: The analysis enabled us to identify various factors associated with late breast cancer screening. Collaboration between health professionals, community organizations and policy-makers is essential to foster an environment conducive to the prevention and early detection of breast cancer. 展开更多
关键词 Associated Factors Late Screening Breast Cancer WOMEN sub-Saharan Africa
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Fluid inclusions and hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area in the Ordos Basin
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作者 Yulin Chen Nan Wu +1 位作者 Yong Feng Jian Wang 《Episodes》 2024年第2期265-278,共14页
Influenced by Late Cretaceous tectonic uplift,fluid inclusion techniques were employed to determine the hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area.There were two fluorescen... Influenced by Late Cretaceous tectonic uplift,fluid inclusion techniques were employed to determine the hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area.There were two fluorescent oil inclusions in the Chang 7_(3) sub-member.The green fluorescent oil inclusions indicated the relatively low-maturity oil,the homogenization temperatures of coeval aqueous inclusions were 83.8-89.5℃.The blue fluorescent oil inclusions indicated the relatively high-maturity oil,the homogenization temperatures of coeval aqueous inclusions exhibited two peaks which were 90.6-109.4℃and 110.1-137.4℃.Combining the burial-thermal history of four wells,there were three stages of hydrocarbon accumulation.A smallscale charging of the relatively low-maturity oil occurred around 131-122 Ma.During the large-scale charging of the high-maturity oil,the hydrocarbon generation of source rock peaked(c.114 to 100 Ma).Late tectonic uplift resulted in an oil adjustment stage(88-72 Ma),corresponding to the high-maturity oil charging time. 展开更多
关键词 hydrocarbon accumulation Chang sub member fluid inclusions homogenization temperatures fluorescent oil inclusions determine hydrocarbon accumulation stages coeval aqueous inclusions fluorescent oil
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Numerical Analysis on the Effect of n-Si on Cu(In, Ga)Se2 Based Thin-Films for High-Performance Solar Cells by 1D-SCAPS
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作者 Rasika N. Mohottige Micheal Farndale +1 位作者 Gary S. Coombs Shahnoza Saburhhojayeva 《Open Journal of Applied Sciences》 2024年第5期1315-1329,共15页
We report the performances of a chalcopyrite Cu(In, Ga)Se<sub>2 </sub>CIGS-based thin-film solar cell with a newly employed high conductive n-Si layer. The data analysis was performed with the help of the ... We report the performances of a chalcopyrite Cu(In, Ga)Se<sub>2 </sub>CIGS-based thin-film solar cell with a newly employed high conductive n-Si layer. The data analysis was performed with the help of the 1D-Solar Cell Capacitance Simulator (1D-SCAPS) software program. The new device structure is based on the CIGS layer as the absorber layer, n-Si as the high conductive layer, i-In<sub>2</sub>S<sub>3</sub>, and i-ZnO as the buffer and window layers, respectively. The optimum CIGS bandgap was determined first and used to simulate and analyze the cell performance throughout the experiment. This analysis revealed that the absorber layer’s optimum bandgap value has to be 1.4 eV to achieve maximum efficiency of 22.57%. Subsequently, output solar cell parameters were analyzed as a function of CIGS layer thickness, defect density, and the operating temperature with an optimized n-Si layer. The newly modeled device has a p-CIGS/n-Si/In<sub>2</sub>S<sub>3</sub>/Al-ZnO structure. The main objective was to improve the overall cell performance while optimizing the thickness of absorber layers, defect density, bandgap, and operating temperature with the newly employed optimized n-Si layer. The increase of absorber layer thickness from 0.2 - 2 µm showed an upward trend in the cell’s performance, while the increase of defect density and operating temperature showed a downward trend in solar cell performance. This study illustrates that the proposed cell structure shows higher cell performances and can be fabricated on the lab-scale and industrial levels. 展开更多
关键词 n-Si p-CIGS 1D-SCAPS Thin-Films In<sub>2sub>S<sub>3sub>
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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 Micro-Nano α-Al<sub>2sub>O<sub>3sub> Waterborne Polyurethane Resin Particle Size Surface Hardness Corrosion Resistance
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